From: Han-Wen Nienhuys <hanwen@xxxxxxxxxx> Reftable is a format for storing the ref database. The rationale and format layout is detailed in commit 35e6c47404 ("reftable: file format documentation", 2020-05-20). This commits imports a fully functioning library for reading and writing reftables, along with unittests. It is suggested to read the code in the following order: * The specification under Documentation/technical/reftable.txt * reftable.h - the public API * record.{c,h} - reading and writing records * block.{c,h} - reading and writing blocks. * reader.{c,h} - reading a complete reftable file. * writer.{c,h} - writing a complete reftable file. * merged.{c,h} and pq.{c,h} - reading a stack of reftables * stack.{c,h} - writing and compacting stacks of reftable on the filesystem. Signed-off-by: Han-Wen Nienhuys <hanwen@xxxxxxxxxx> --- reftable/LICENSE | 31 + reftable/VERSION | 1 + reftable/basics.c | 215 +++++++ reftable/basics.h | 53 ++ reftable/block.c | 432 +++++++++++++ reftable/block.h | 129 ++++ reftable/block_test.c | 157 +++++ reftable/compat.c | 98 +++ reftable/compat.h | 48 ++ reftable/constants.h | 21 + reftable/dump.c | 212 +++++++ reftable/file.c | 95 +++ reftable/iter.c | 242 ++++++++ reftable/iter.h | 72 +++ reftable/merged.c | 321 ++++++++++ reftable/merged.h | 39 ++ reftable/merged_test.c | 273 +++++++++ reftable/pq.c | 115 ++++ reftable/pq.h | 34 ++ reftable/reader.c | 744 +++++++++++++++++++++++ reftable/reader.h | 65 ++ reftable/record.c | 1126 ++++++++++++++++++++++++++++++++++ reftable/record.h | 143 +++++ reftable/record_test.c | 410 +++++++++++++ reftable/refname.c | 209 +++++++ reftable/refname.h | 38 ++ reftable/refname_test.c | 99 +++ reftable/reftable-tests.h | 22 + reftable/reftable.c | 90 +++ reftable/reftable.h | 571 ++++++++++++++++++ reftable/reftable_test.c | 631 +++++++++++++++++++ reftable/stack.c | 1209 +++++++++++++++++++++++++++++++++++++ reftable/stack.h | 48 ++ reftable/stack_test.c | 787 ++++++++++++++++++++++++ reftable/strbuf.c | 206 +++++++ reftable/strbuf.h | 88 +++ reftable/strbuf_test.c | 39 ++ reftable/system.h | 53 ++ reftable/test_framework.c | 69 +++ reftable/test_framework.h | 64 ++ reftable/tree.c | 63 ++ reftable/tree.h | 34 ++ reftable/tree_test.c | 62 ++ reftable/update.sh | 22 + reftable/writer.c | 662 ++++++++++++++++++++ reftable/writer.h | 60 ++ reftable/zlib-compat.c | 92 +++ 47 files changed, 10294 insertions(+) create mode 100644 reftable/LICENSE create mode 100644 reftable/VERSION create mode 100644 reftable/basics.c create mode 100644 reftable/basics.h create mode 100644 reftable/block.c create mode 100644 reftable/block.h create mode 100644 reftable/block_test.c create mode 100644 reftable/compat.c create mode 100644 reftable/compat.h create mode 100644 reftable/constants.h create mode 100644 reftable/dump.c create mode 100644 reftable/file.c create mode 100644 reftable/iter.c create mode 100644 reftable/iter.h create mode 100644 reftable/merged.c create mode 100644 reftable/merged.h create mode 100644 reftable/merged_test.c create mode 100644 reftable/pq.c create mode 100644 reftable/pq.h create mode 100644 reftable/reader.c create mode 100644 reftable/reader.h create mode 100644 reftable/record.c create mode 100644 reftable/record.h create mode 100644 reftable/record_test.c create mode 100644 reftable/refname.c create mode 100644 reftable/refname.h create mode 100644 reftable/refname_test.c create mode 100644 reftable/reftable-tests.h create mode 100644 reftable/reftable.c create mode 100644 reftable/reftable.h create mode 100644 reftable/reftable_test.c create mode 100644 reftable/stack.c create mode 100644 reftable/stack.h create mode 100644 reftable/stack_test.c create mode 100644 reftable/strbuf.c create mode 100644 reftable/strbuf.h create mode 100644 reftable/strbuf_test.c create mode 100644 reftable/system.h create mode 100644 reftable/test_framework.c create mode 100644 reftable/test_framework.h create mode 100644 reftable/tree.c create mode 100644 reftable/tree.h create mode 100644 reftable/tree_test.c create mode 100755 reftable/update.sh create mode 100644 reftable/writer.c create mode 100644 reftable/writer.h create mode 100644 reftable/zlib-compat.c diff --git a/reftable/LICENSE b/reftable/LICENSE new file mode 100644 index 00000000000..402e0f9356b --- /dev/null +++ b/reftable/LICENSE @@ -0,0 +1,31 @@ +BSD License + +Copyright (c) 2020, Google LLC +All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are +met: + +* Redistributions of source code must retain the above copyright notice, +this list of conditions and the following disclaimer. + +* Redistributions in binary form must reproduce the above copyright +notice, this list of conditions and the following disclaimer in the +documentation and/or other materials provided with the distribution. + +* Neither the name of Google LLC nor the names of its contributors may +be used to endorse or promote products derived from this software +without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/reftable/VERSION b/reftable/VERSION new file mode 100644 index 00000000000..21aced024b7 --- /dev/null +++ b/reftable/VERSION @@ -0,0 +1 @@ +d7472cbd1afe6bf3da53e94971b1cc79ce183fa8 Remove outdated bits of the README file diff --git a/reftable/basics.c b/reftable/basics.c new file mode 100644 index 00000000000..e5110ab6ac4 --- /dev/null +++ b/reftable/basics.c @@ -0,0 +1,215 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "basics.h" + +#include "system.h" + +void put_be24(uint8_t *out, uint32_t i) +{ + out[0] = (uint8_t)((i >> 16) & 0xff); + out[1] = (uint8_t)((i >> 8) & 0xff); + out[2] = (uint8_t)(i & 0xff); +} + +uint32_t get_be24(uint8_t *in) +{ + return (uint32_t)(in[0]) << 16 | (uint32_t)(in[1]) << 8 | + (uint32_t)(in[2]); +} + +void put_be16(uint8_t *out, uint16_t i) +{ + out[0] = (uint8_t)((i >> 8) & 0xff); + out[1] = (uint8_t)(i & 0xff); +} + +int binsearch(size_t sz, int (*f)(size_t k, void *args), void *args) +{ + size_t lo = 0; + size_t hi = sz; + + /* invariant: (hi == sz) || f(hi) == true + (lo == 0 && f(0) == true) || fi(lo) == false + */ + while (hi - lo > 1) { + size_t mid = lo + (hi - lo) / 2; + + int val = f(mid, args); + if (val) { + hi = mid; + } else { + lo = mid; + } + } + + if (lo == 0) { + if (f(0, args)) { + return 0; + } else { + return 1; + } + } + + return hi; +} + +void free_names(char **a) +{ + char **p = a; + if (p == NULL) { + return; + } + while (*p) { + reftable_free(*p); + p++; + } + reftable_free(a); +} + +int names_length(char **names) +{ + int len = 0; + char **p = names; + while (*p) { + p++; + len++; + } + return len; +} + +void parse_names(char *buf, int size, char ***namesp) +{ + char **names = NULL; + int names_cap = 0; + int names_len = 0; + + char *p = buf; + char *end = buf + size; + while (p < end) { + char *next = strchr(p, '\n'); + if (next != NULL) { + *next = 0; + } else { + next = end; + } + if (p < next) { + if (names_len == names_cap) { + names_cap = 2 * names_cap + 1; + names = reftable_realloc( + names, names_cap * sizeof(char *)); + } + names[names_len++] = xstrdup(p); + } + p = next + 1; + } + + if (names_len == names_cap) { + names_cap = 2 * names_cap + 1; + names = reftable_realloc(names, names_cap * sizeof(char *)); + } + + names[names_len] = NULL; + *namesp = names; +} + +int names_equal(char **a, char **b) +{ + while (*a && *b) { + if (strcmp(*a, *b)) { + return 0; + } + + a++; + b++; + } + + return *a == *b; +} + +const char *reftable_error_str(int err) +{ + static char buf[250]; + switch (err) { + case REFTABLE_IO_ERROR: + return "I/O error"; + case REFTABLE_FORMAT_ERROR: + return "corrupt reftable file"; + case REFTABLE_NOT_EXIST_ERROR: + return "file does not exist"; + case REFTABLE_LOCK_ERROR: + return "data is outdated"; + case REFTABLE_API_ERROR: + return "misuse of the reftable API"; + case REFTABLE_ZLIB_ERROR: + return "zlib failure"; + case REFTABLE_NAME_CONFLICT: + return "file/directory conflict"; + case REFTABLE_REFNAME_ERROR: + return "invalid refname"; + case -1: + return "general error"; + default: + snprintf(buf, sizeof(buf), "unknown error code %d", err); + return buf; + } +} + +int reftable_error_to_errno(int err) +{ + switch (err) { + case REFTABLE_IO_ERROR: + return EIO; + case REFTABLE_FORMAT_ERROR: + return EFAULT; + case REFTABLE_NOT_EXIST_ERROR: + return ENOENT; + case REFTABLE_LOCK_ERROR: + return EBUSY; + case REFTABLE_API_ERROR: + return EINVAL; + case REFTABLE_ZLIB_ERROR: + return EDOM; + default: + return ERANGE; + } +} + +void *(*reftable_malloc_ptr)(size_t sz) = &malloc; +void *(*reftable_realloc_ptr)(void *, size_t) = &realloc; +void (*reftable_free_ptr)(void *) = &free; + +void *reftable_malloc(size_t sz) +{ + return (*reftable_malloc_ptr)(sz); +} + +void *reftable_realloc(void *p, size_t sz) +{ + return (*reftable_realloc_ptr)(p, sz); +} + +void reftable_free(void *p) +{ + reftable_free_ptr(p); +} + +void *reftable_calloc(size_t sz) +{ + void *p = reftable_malloc(sz); + memset(p, 0, sz); + return p; +} + +void reftable_set_alloc(void *(*malloc)(size_t), + void *(*realloc)(void *, size_t), void (*free)(void *)) +{ + reftable_malloc_ptr = malloc; + reftable_realloc_ptr = realloc; + reftable_free_ptr = free; +} diff --git a/reftable/basics.h b/reftable/basics.h new file mode 100644 index 00000000000..e1b4c9fa1a1 --- /dev/null +++ b/reftable/basics.h @@ -0,0 +1,53 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef BASICS_H +#define BASICS_H + +#include "system.h" + +#include "reftable.h" + +#define true 1 +#define false 0 + +/* Bigendian en/decoding of integers */ + +void put_be24(uint8_t *out, uint32_t i); +uint32_t get_be24(uint8_t *in); +void put_be16(uint8_t *out, uint16_t i); + +/* + find smallest index i in [0, sz) at which f(i) is true, assuming + that f is ascending. Return sz if f(i) is false for all indices. +*/ +int binsearch(size_t sz, int (*f)(size_t k, void *args), void *args); + +/* + Frees a NULL terminated array of malloced strings. The array itself is also + freed. + */ +void free_names(char **a); + +/* parse a newline separated list of names. Empty names are discarded. */ +void parse_names(char *buf, int size, char ***namesp); + +/* compares two NULL-terminated arrays of strings. */ +int names_equal(char **a, char **b); + +/* returns the array size of a NULL-terminated array of strings. */ +int names_length(char **names); + +/* Allocation routines; they invoke the functions set through + * reftable_set_alloc() */ +void *reftable_malloc(size_t sz); +void *reftable_realloc(void *p, size_t sz); +void reftable_free(void *p); +void *reftable_calloc(size_t sz); + +#endif diff --git a/reftable/block.c b/reftable/block.c new file mode 100644 index 00000000000..d6a1a42a2ba --- /dev/null +++ b/reftable/block.c @@ -0,0 +1,432 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "block.h" + +#include "system.h" + +#include "constants.h" +#include "record.h" +#include "reftable.h" +#include "zlib.h" + +int header_size(int version) +{ + switch (version) { + case 1: + return 24; + case 2: + return 28; + } + abort(); +} + +int footer_size(int version) +{ + switch (version) { + case 1: + return 68; + case 2: + return 72; + } + abort(); +} + +int block_writer_register_restart(struct block_writer *w, int n, bool restart, + struct strbuf *key); + +void block_writer_init(struct block_writer *bw, uint8_t typ, uint8_t *buf, + uint32_t block_size, uint32_t header_off, int hash_size) +{ + bw->buf = buf; + bw->hash_size = hash_size; + bw->block_size = block_size; + bw->header_off = header_off; + bw->buf[header_off] = typ; + bw->next = header_off + 4; + bw->restart_interval = 16; + bw->entries = 0; + bw->restart_len = 0; + bw->last_key.len = 0; +} + +uint8_t block_writer_type(struct block_writer *bw) +{ + return bw->buf[bw->header_off]; +} + +/* adds the reftable_record to the block. Returns -1 if it does not fit, 0 on + success */ +int block_writer_add(struct block_writer *w, struct reftable_record *rec) +{ + struct strbuf empty = STRBUF_INIT; + struct strbuf last = + w->entries % w->restart_interval == 0 ? empty : w->last_key; + struct string_view out = { + .buf = w->buf + w->next, + .len = w->block_size - w->next, + }; + + struct string_view start = out; + + bool restart = false; + struct strbuf key = STRBUF_INIT; + int n = 0; + + reftable_record_key(rec, &key); + n = reftable_encode_key(&restart, out, last, key, + reftable_record_val_type(rec)); + if (n < 0) + goto done; + string_view_consume(&out, n); + + n = reftable_record_encode(rec, out, w->hash_size); + if (n < 0) + goto done; + string_view_consume(&out, n); + + if (block_writer_register_restart(w, start.len - out.len, restart, + &key) < 0) + goto done; + + strbuf_release(&key); + return 0; + +done: + strbuf_release(&key); + return -1; +} + +int block_writer_register_restart(struct block_writer *w, int n, bool restart, + struct strbuf *key) +{ + int rlen = w->restart_len; + if (rlen >= MAX_RESTARTS) { + restart = false; + } + + if (restart) { + rlen++; + } + if (2 + 3 * rlen + n > w->block_size - w->next) + return -1; + if (restart) { + if (w->restart_len == w->restart_cap) { + w->restart_cap = w->restart_cap * 2 + 1; + w->restarts = reftable_realloc( + w->restarts, sizeof(uint32_t) * w->restart_cap); + } + + w->restarts[w->restart_len++] = w->next; + } + + w->next += n; + + strbuf_reset(&w->last_key); + strbuf_addbuf(&w->last_key, key); + w->entries++; + return 0; +} + +int block_writer_finish(struct block_writer *w) +{ + int i = 0; + for (i = 0; i < w->restart_len; i++) { + put_be24(w->buf + w->next, w->restarts[i]); + w->next += 3; + } + + put_be16(w->buf + w->next, w->restart_len); + w->next += 2; + put_be24(w->buf + 1 + w->header_off, w->next); + + if (block_writer_type(w) == BLOCK_TYPE_LOG) { + int block_header_skip = 4 + w->header_off; + uint8_t *compressed = NULL; + int zresult = 0; + uLongf src_len = w->next - block_header_skip; + size_t dest_cap = src_len; + + compressed = reftable_malloc(dest_cap); + while (1) { + uLongf out_dest_len = dest_cap; + + zresult = compress2(compressed, &out_dest_len, + w->buf + block_header_skip, src_len, + 9); + if (zresult == Z_BUF_ERROR) { + dest_cap *= 2; + compressed = + reftable_realloc(compressed, dest_cap); + continue; + } + + if (Z_OK != zresult) { + reftable_free(compressed); + return REFTABLE_ZLIB_ERROR; + } + + memcpy(w->buf + block_header_skip, compressed, + out_dest_len); + w->next = out_dest_len + block_header_skip; + reftable_free(compressed); + break; + } + } + return w->next; +} + +uint8_t block_reader_type(struct block_reader *r) +{ + return r->block.data[r->header_off]; +} + +int block_reader_init(struct block_reader *br, struct reftable_block *block, + uint32_t header_off, uint32_t table_block_size, + int hash_size) +{ + uint32_t full_block_size = table_block_size; + uint8_t typ = block->data[header_off]; + uint32_t sz = get_be24(block->data + header_off + 1); + + uint16_t restart_count = 0; + uint32_t restart_start = 0; + uint8_t *restart_bytes = NULL; + + if (!reftable_is_block_type(typ)) + return REFTABLE_FORMAT_ERROR; + + if (typ == BLOCK_TYPE_LOG) { + int block_header_skip = 4 + header_off; + uLongf dst_len = sz - block_header_skip; /* total size of dest + buffer. */ + uLongf src_len = block->len - block_header_skip; + /* Log blocks specify the *uncompressed* size in their header. + */ + uint8_t *uncompressed = reftable_malloc(sz); + + /* Copy over the block header verbatim. It's not compressed. */ + memcpy(uncompressed, block->data, block_header_skip); + + /* Uncompress */ + if (Z_OK != uncompress_return_consumed( + uncompressed + block_header_skip, &dst_len, + block->data + block_header_skip, + &src_len)) { + reftable_free(uncompressed); + return REFTABLE_ZLIB_ERROR; + } + + if (dst_len + block_header_skip != sz) + return REFTABLE_FORMAT_ERROR; + + /* We're done with the input data. */ + reftable_block_done(block); + block->data = uncompressed; + block->len = sz; + block->source = malloc_block_source(); + full_block_size = src_len + block_header_skip; + } else if (full_block_size == 0) { + full_block_size = sz; + } else if (sz < full_block_size && sz < block->len && + block->data[sz] != 0) { + /* If the block is smaller than the full block size, it is + padded (data followed by '\0') or the next block is + unaligned. */ + full_block_size = sz; + } + + restart_count = get_be16(block->data + sz - 2); + restart_start = sz - 2 - 3 * restart_count; + restart_bytes = block->data + restart_start; + + /* transfer ownership. */ + br->block = *block; + block->data = NULL; + block->len = 0; + + br->hash_size = hash_size; + br->block_len = restart_start; + br->full_block_size = full_block_size; + br->header_off = header_off; + br->restart_count = restart_count; + br->restart_bytes = restart_bytes; + + return 0; +} + +static uint32_t block_reader_restart_offset(struct block_reader *br, int i) +{ + return get_be24(br->restart_bytes + 3 * i); +} + +void block_reader_start(struct block_reader *br, struct block_iter *it) +{ + it->br = br; + strbuf_reset(&it->last_key); + it->next_off = br->header_off + 4; +} + +struct restart_find_args { + int error; + struct strbuf key; + struct block_reader *r; +}; + +static int restart_key_less(size_t idx, void *args) +{ + struct restart_find_args *a = (struct restart_find_args *)args; + uint32_t off = block_reader_restart_offset(a->r, idx); + struct string_view in = { + .buf = a->r->block.data + off, + .len = a->r->block_len - off, + }; + + /* the restart key is verbatim in the block, so this could avoid the + alloc for decoding the key */ + struct strbuf rkey = STRBUF_INIT; + struct strbuf last_key = STRBUF_INIT; + uint8_t unused_extra; + int n = reftable_decode_key(&rkey, &unused_extra, last_key, in); + int result; + if (n < 0) { + a->error = 1; + return -1; + } + + result = strbuf_cmp(&a->key, &rkey); + strbuf_release(&rkey); + return result; +} + +void block_iter_copy_from(struct block_iter *dest, struct block_iter *src) +{ + dest->br = src->br; + dest->next_off = src->next_off; + strbuf_reset(&dest->last_key); + strbuf_addbuf(&dest->last_key, &src->last_key); +} + +int block_iter_next(struct block_iter *it, struct reftable_record *rec) +{ + struct string_view in = { + .buf = it->br->block.data + it->next_off, + .len = it->br->block_len - it->next_off, + }; + struct string_view start = in; + struct strbuf key = STRBUF_INIT; + uint8_t extra = 0; + int n = 0; + + if (it->next_off >= it->br->block_len) + return 1; + + n = reftable_decode_key(&key, &extra, it->last_key, in); + if (n < 0) + return -1; + + string_view_consume(&in, n); + n = reftable_record_decode(rec, key, extra, in, it->br->hash_size); + if (n < 0) + return -1; + string_view_consume(&in, n); + + strbuf_reset(&it->last_key); + strbuf_addbuf(&it->last_key, &key); + it->next_off += start.len - in.len; + strbuf_release(&key); + return 0; +} + +int block_reader_first_key(struct block_reader *br, struct strbuf *key) +{ + struct strbuf empty = STRBUF_INIT; + int off = br->header_off + 4; + struct string_view in = { + .buf = br->block.data + off, + .len = br->block_len - off, + }; + + uint8_t extra = 0; + int n = reftable_decode_key(key, &extra, empty, in); + if (n < 0) + return n; + + return 0; +} + +int block_iter_seek(struct block_iter *it, struct strbuf *want) +{ + return block_reader_seek(it->br, it, want); +} + +void block_iter_close(struct block_iter *it) +{ + strbuf_release(&it->last_key); +} + +int block_reader_seek(struct block_reader *br, struct block_iter *it, + struct strbuf *want) +{ + struct restart_find_args args = { + .key = *want, + .r = br, + }; + struct reftable_record rec = reftable_new_record(block_reader_type(br)); + struct strbuf key = STRBUF_INIT; + int err = 0; + struct block_iter next = { + .last_key = STRBUF_INIT, + }; + + int i = binsearch(br->restart_count, &restart_key_less, &args); + if (args.error) { + err = REFTABLE_FORMAT_ERROR; + goto done; + } + + it->br = br; + if (i > 0) { + i--; + it->next_off = block_reader_restart_offset(br, i); + } else { + it->next_off = br->header_off + 4; + } + + /* We're looking for the last entry less/equal than the wanted key, so + we have to go one entry too far and then back up. + */ + while (true) { + block_iter_copy_from(&next, it); + err = block_iter_next(&next, &rec); + if (err < 0) + goto done; + + reftable_record_key(&rec, &key); + if (err > 0 || strbuf_cmp(&key, want) >= 0) { + err = 0; + goto done; + } + + block_iter_copy_from(it, &next); + } + +done: + strbuf_release(&key); + strbuf_release(&next.last_key); + reftable_record_destroy(&rec); + + return err; +} + +void block_writer_clear(struct block_writer *bw) +{ + FREE_AND_NULL(bw->restarts); + strbuf_release(&bw->last_key); + /* the block is not owned. */ +} diff --git a/reftable/block.h b/reftable/block.h new file mode 100644 index 00000000000..14a6f835f46 --- /dev/null +++ b/reftable/block.h @@ -0,0 +1,129 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef BLOCK_H +#define BLOCK_H + +#include "basics.h" +#include "record.h" +#include "reftable.h" + +/* + Writes reftable blocks. The block_writer is reused across blocks to minimize + allocation overhead. +*/ +struct block_writer { + uint8_t *buf; + uint32_t block_size; + + /* Offset ofof the global header. Nonzero in the first block only. */ + uint32_t header_off; + + /* How often to restart keys. */ + int restart_interval; + int hash_size; + + /* Offset of next uint8_t to write. */ + uint32_t next; + uint32_t *restarts; + uint32_t restart_len; + uint32_t restart_cap; + + struct strbuf last_key; + int entries; +}; + +/* + initializes the blockwriter to write `typ` entries, using `buf` as temporary + storage. `buf` is not owned by the block_writer. */ +void block_writer_init(struct block_writer *bw, uint8_t typ, uint8_t *buf, + uint32_t block_size, uint32_t header_off, int hash_size); + +/* + returns the block type (eg. 'r' for ref records. +*/ +uint8_t block_writer_type(struct block_writer *bw); + +/* appends the record, or -1 if it doesn't fit. */ +int block_writer_add(struct block_writer *w, struct reftable_record *rec); + +/* appends the key restarts, and compress the block if necessary. */ +int block_writer_finish(struct block_writer *w); + +/* clears out internally allocated block_writer members. */ +void block_writer_clear(struct block_writer *bw); + +/* Read a block. */ +struct block_reader { + /* offset of the block header; nonzero for the first block in a + * reftable. */ + uint32_t header_off; + + /* the memory block */ + struct reftable_block block; + int hash_size; + + /* size of the data, excluding restart data. */ + uint32_t block_len; + uint8_t *restart_bytes; + uint16_t restart_count; + + /* size of the data in the file. For log blocks, this is the compressed + * size. */ + uint32_t full_block_size; +}; + +/* Iterate over entries in a block */ +struct block_iter { + /* offset within the block of the next entry to read. */ + uint32_t next_off; + struct block_reader *br; + + /* key for last entry we read. */ + struct strbuf last_key; +}; + +/* initializes a block reader. */ +int block_reader_init(struct block_reader *br, struct reftable_block *bl, + uint32_t header_off, uint32_t table_block_size, + int hash_size); + +/* Position `it` at start of the block */ +void block_reader_start(struct block_reader *br, struct block_iter *it); + +/* Position `it` to the `want` key in the block */ +int block_reader_seek(struct block_reader *br, struct block_iter *it, + struct strbuf *want); + +/* Returns the block type (eg. 'r' for refs) */ +uint8_t block_reader_type(struct block_reader *r); + +/* Decodes the first key in the block */ +int block_reader_first_key(struct block_reader *br, struct strbuf *key); + +void block_iter_copy_from(struct block_iter *dest, struct block_iter *src); + +/* return < 0 for error, 0 for OK, > 0 for EOF. */ +int block_iter_next(struct block_iter *it, struct reftable_record *rec); + +/* Seek to `want` with in the block pointed to by `it` */ +int block_iter_seek(struct block_iter *it, struct strbuf *want); + +/* deallocate memory for `it`. The block reader and its block is left intact. */ +void block_iter_close(struct block_iter *it); + +/* size of file header, depending on format version */ +int header_size(int version); + +/* size of file footer, depending on format version */ +int footer_size(int version); + +/* returns a block to its source. */ +void reftable_block_done(struct reftable_block *ret); + +#endif diff --git a/reftable/block_test.c b/reftable/block_test.c new file mode 100644 index 00000000000..d9b347e31fa --- /dev/null +++ b/reftable/block_test.c @@ -0,0 +1,157 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "block.h" + +#include "system.h" + +#include "basics.h" +#include "constants.h" +#include "record.h" +#include "reftable.h" +#include "test_framework.h" +#include "reftable-tests.h" + +struct binsearch_args { + int key; + int *arr; +}; + +static int binsearch_func(size_t i, void *void_args) +{ + struct binsearch_args *args = (struct binsearch_args *)void_args; + + return args->key < args->arr[i]; +} + +static void test_binsearch(void) +{ + int arr[] = { 2, 4, 6, 8, 10 }; + size_t sz = ARRAY_SIZE(arr); + struct binsearch_args args = { + .arr = arr, + }; + + int i = 0; + for (i = 1; i < 11; i++) { + int res; + args.key = i; + res = binsearch(sz, &binsearch_func, &args); + + if (res < sz) { + assert(args.key < arr[res]); + if (res > 0) { + assert(args.key >= arr[res - 1]); + } + } else { + assert(args.key == 10 || args.key == 11); + } + } +} + +static void test_block_read_write(void) +{ + const int header_off = 21; /* random */ + char *names[30]; + const int N = ARRAY_SIZE(names); + const int block_size = 1024; + struct reftable_block block = { 0 }; + struct block_writer bw = { + .last_key = STRBUF_INIT, + }; + struct reftable_ref_record ref = { 0 }; + struct reftable_record rec = { 0 }; + int i = 0; + int n; + struct block_reader br = { 0 }; + struct block_iter it = { .last_key = STRBUF_INIT }; + int j = 0; + struct strbuf want = STRBUF_INIT; + + block.data = reftable_calloc(block_size); + block.len = block_size; + block.source = malloc_block_source(); + block_writer_init(&bw, BLOCK_TYPE_REF, block.data, block_size, + header_off, hash_size(SHA1_ID)); + reftable_record_from_ref(&rec, &ref); + + for (i = 0; i < N; i++) { + char name[100]; + uint8_t hash[SHA1_SIZE]; + snprintf(name, sizeof(name), "branch%02d", i); + memset(hash, i, sizeof(hash)); + + ref.ref_name = name; + ref.value = hash; + names[i] = xstrdup(name); + n = block_writer_add(&bw, &rec); + ref.ref_name = NULL; + ref.value = NULL; + assert(n == 0); + } + + n = block_writer_finish(&bw); + assert(n > 0); + + block_writer_clear(&bw); + + block_reader_init(&br, &block, header_off, block_size, SHA1_SIZE); + + block_reader_start(&br, &it); + + while (true) { + int r = block_iter_next(&it, &rec); + assert(r >= 0); + if (r > 0) { + break; + } + assert_streq(names[j], ref.ref_name); + j++; + } + + reftable_record_clear(&rec); + block_iter_close(&it); + + for (i = 0; i < N; i++) { + struct block_iter it = { .last_key = STRBUF_INIT }; + strbuf_reset(&want); + strbuf_addstr(&want, names[i]); + + n = block_reader_seek(&br, &it, &want); + assert(n == 0); + + n = block_iter_next(&it, &rec); + assert(n == 0); + + assert_streq(names[i], ref.ref_name); + + want.len--; + n = block_reader_seek(&br, &it, &want); + assert(n == 0); + + n = block_iter_next(&it, &rec); + assert(n == 0); + assert_streq(names[10 * (i / 10)], ref.ref_name); + + block_iter_close(&it); + } + + reftable_record_clear(&rec); + reftable_block_done(&br.block); + strbuf_release(&want); + for (i = 0; i < N; i++) { + reftable_free(names[i]); + } +} + +int block_test_main(int argc, const char *argv[]) +{ + add_test_case("binsearch", &test_binsearch); + add_test_case("block_read_write", &test_block_read_write); + return test_main(argc, argv); +} diff --git a/reftable/compat.c b/reftable/compat.c new file mode 100644 index 00000000000..be0fd65d2f0 --- /dev/null +++ b/reftable/compat.c @@ -0,0 +1,98 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd + +*/ + +/* compat.c - compatibility functions for standalone compilation */ + +#include "system.h" +#include "basics.h" + +#ifdef REFTABLE_STANDALONE + +#include <dirent.h> + +void put_be32(void *p, uint32_t i) +{ + uint8_t *out = (uint8_t *)p; + + out[0] = (uint8_t)((i >> 24) & 0xff); + out[1] = (uint8_t)((i >> 16) & 0xff); + out[2] = (uint8_t)((i >> 8) & 0xff); + out[3] = (uint8_t)((i)&0xff); +} + +uint32_t get_be32(uint8_t *in) +{ + return (uint32_t)(in[0]) << 24 | (uint32_t)(in[1]) << 16 | + (uint32_t)(in[2]) << 8 | (uint32_t)(in[3]); +} + +void put_be64(void *p, uint64_t v) +{ + uint8_t *out = (uint8_t *)p; + int i = sizeof(uint64_t); + while (i--) { + out[i] = (uint8_t)(v & 0xff); + v >>= 8; + } +} + +uint64_t get_be64(void *out) +{ + uint8_t *bytes = (uint8_t *)out; + uint64_t v = 0; + int i = 0; + for (i = 0; i < sizeof(uint64_t); i++) { + v = (v << 8) | (uint8_t)(bytes[i] & 0xff); + } + return v; +} + +uint16_t get_be16(uint8_t *in) +{ + return (uint32_t)(in[0]) << 8 | (uint32_t)(in[1]); +} + +char *xstrdup(const char *s) +{ + int l = strlen(s); + char *dest = (char *)reftable_malloc(l + 1); + strncpy(dest, s, l + 1); + return dest; +} + +void sleep_millisec(int millisecs) +{ + usleep(millisecs * 1000); +} + +void reftable_clear_dir(const char *dirname) +{ + DIR *dir = opendir(dirname); + struct dirent *ent = NULL; + assert(dir); + while ((ent = readdir(dir)) != NULL) { + unlinkat(dirfd(dir), ent->d_name, 0); + } + closedir(dir); + rmdir(dirname); +} + +#else + +#include "../dir.h" + +void reftable_clear_dir(const char *dirname) +{ + struct strbuf path = STRBUF_INIT; + strbuf_addstr(&path, dirname); + remove_dir_recursively(&path, 0); + strbuf_release(&path); +} + +#endif diff --git a/reftable/compat.h b/reftable/compat.h new file mode 100644 index 00000000000..a765c57e966 --- /dev/null +++ b/reftable/compat.h @@ -0,0 +1,48 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef COMPAT_H +#define COMPAT_H + +#include "system.h" + +#ifdef REFTABLE_STANDALONE + +/* functions that git-core provides, for standalone compilation */ +#include <stdint.h> + +uint64_t get_be64(void *in); +void put_be64(void *out, uint64_t i); + +void put_be32(void *out, uint32_t i); +uint32_t get_be32(uint8_t *in); + +uint16_t get_be16(uint8_t *in); + +#define ARRAY_SIZE(a) sizeof((a)) / sizeof((a)[0]) +#define FREE_AND_NULL(x) \ + do { \ + reftable_free(x); \ + (x) = NULL; \ + } while (0) +#define QSORT(arr, n, cmp) qsort(arr, n, sizeof(arr[0]), cmp) +#define SWAP(a, b) \ + { \ + char tmp[sizeof(a)]; \ + assert(sizeof(a) == sizeof(b)); \ + memcpy(&tmp[0], &a, sizeof(a)); \ + memcpy(&a, &b, sizeof(a)); \ + memcpy(&b, &tmp[0], sizeof(a)); \ + } + +char *xstrdup(const char *s); + +void sleep_millisec(int millisecs); + +#endif +#endif diff --git a/reftable/constants.h b/reftable/constants.h new file mode 100644 index 00000000000..5eee72c4c11 --- /dev/null +++ b/reftable/constants.h @@ -0,0 +1,21 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef CONSTANTS_H +#define CONSTANTS_H + +#define BLOCK_TYPE_LOG 'g' +#define BLOCK_TYPE_INDEX 'i' +#define BLOCK_TYPE_REF 'r' +#define BLOCK_TYPE_OBJ 'o' +#define BLOCK_TYPE_ANY 0 + +#define MAX_RESTARTS ((1 << 16) - 1) +#define DEFAULT_BLOCK_SIZE 4096 + +#endif diff --git a/reftable/dump.c b/reftable/dump.c new file mode 100644 index 00000000000..00b444e8c9b --- /dev/null +++ b/reftable/dump.c @@ -0,0 +1,212 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include <stddef.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <string.h> + +#include "reftable.h" +#include "reftable-tests.h" + +static uint32_t hash_id; + +static int dump_table(const char *tablename) +{ + struct reftable_block_source src = { 0 }; + int err = reftable_block_source_from_file(&src, tablename); + struct reftable_iterator it = { 0 }; + struct reftable_ref_record ref = { 0 }; + struct reftable_log_record log = { 0 }; + struct reftable_reader *r = NULL; + + if (err < 0) + return err; + + err = reftable_new_reader(&r, &src, tablename); + if (err < 0) + return err; + + err = reftable_reader_seek_ref(r, &it, ""); + if (err < 0) { + return err; + } + + while (1) { + err = reftable_iterator_next_ref(&it, &ref); + if (err > 0) { + break; + } + if (err < 0) { + return err; + } + reftable_ref_record_print(&ref, hash_id); + } + reftable_iterator_destroy(&it); + reftable_ref_record_clear(&ref); + + err = reftable_reader_seek_log(r, &it, ""); + if (err < 0) { + return err; + } + while (1) { + err = reftable_iterator_next_log(&it, &log); + if (err > 0) { + break; + } + if (err < 0) { + return err; + } + reftable_log_record_print(&log, hash_id); + } + reftable_iterator_destroy(&it); + reftable_log_record_clear(&log); + + reftable_reader_free(r); + return 0; +} + +static int compact_stack(const char *stackdir) +{ + struct reftable_stack *stack = NULL; + struct reftable_write_options cfg = {}; + + int err = reftable_new_stack(&stack, stackdir, cfg); + if (err < 0) + goto done; + + err = reftable_stack_compact_all(stack, NULL); + if (err < 0) + goto done; +done: + if (stack != NULL) { + reftable_stack_destroy(stack); + } + return err; +} + +static int dump_stack(const char *stackdir) +{ + struct reftable_stack *stack = NULL; + struct reftable_write_options cfg = {}; + struct reftable_iterator it = { 0 }; + struct reftable_ref_record ref = { 0 }; + struct reftable_log_record log = { 0 }; + struct reftable_merged_table *merged = NULL; + + int err = reftable_new_stack(&stack, stackdir, cfg); + if (err < 0) + return err; + + merged = reftable_stack_merged_table(stack); + + err = reftable_merged_table_seek_ref(merged, &it, ""); + if (err < 0) { + return err; + } + + while (1) { + err = reftable_iterator_next_ref(&it, &ref); + if (err > 0) { + break; + } + if (err < 0) { + return err; + } + reftable_ref_record_print(&ref, hash_id); + } + reftable_iterator_destroy(&it); + reftable_ref_record_clear(&ref); + + err = reftable_merged_table_seek_log(merged, &it, ""); + if (err < 0) { + return err; + } + while (1) { + err = reftable_iterator_next_log(&it, &log); + if (err > 0) { + break; + } + if (err < 0) { + return err; + } + reftable_log_record_print(&log, hash_id); + } + reftable_iterator_destroy(&it); + reftable_log_record_clear(&log); + + reftable_stack_destroy(stack); + return 0; +} + +static void print_help(void) +{ + printf("usage: dump [-cst] arg\n\n" + "options: \n" + " -c compact\n" + " -t dump table\n" + " -s dump stack\n" + " -h this help\n" + " -2 use SHA256\n" + "\n"); +} + +int reftable_dump_main(int argc, char *const *argv) +{ + int err = 0; + int opt; + int opt_dump_table = 0; + int opt_dump_stack = 0; + int opt_compact = 0; + const char *arg = NULL; + while ((opt = getopt(argc, argv, "2chts")) != -1) { + switch (opt) { + case '2': + hash_id = 0x73323536; + break; + case 't': + opt_dump_table = 1; + break; + case 's': + opt_dump_stack = 1; + break; + case 'c': + opt_compact = 1; + break; + case '?': + case 'h': + print_help(); + return 2; + break; + } + } + + if (argv[optind] == NULL) { + fprintf(stderr, "need argument\n"); + print_help(); + return 2; + } + + arg = argv[optind]; + + if (opt_dump_table) { + err = dump_table(arg); + } else if (opt_dump_stack) { + err = dump_stack(arg); + } else if (opt_compact) { + err = compact_stack(arg); + } + + if (err < 0) { + fprintf(stderr, "%s: %s: %s\n", argv[0], arg, + reftable_error_str(err)); + return 1; + } + return 0; +} diff --git a/reftable/file.c b/reftable/file.c new file mode 100644 index 00000000000..eacf41f23b4 --- /dev/null +++ b/reftable/file.c @@ -0,0 +1,95 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "system.h" + +#include "block.h" +#include "iter.h" +#include "record.h" +#include "reftable.h" +#include "tree.h" + +struct file_block_source { + int fd; + uint64_t size; +}; + +static uint64_t file_size(void *b) +{ + return ((struct file_block_source *)b)->size; +} + +static void file_return_block(void *b, struct reftable_block *dest) +{ + memset(dest->data, 0xff, dest->len); + reftable_free(dest->data); +} + +static void file_close(void *b) +{ + int fd = ((struct file_block_source *)b)->fd; + if (fd > 0) { + close(fd); + ((struct file_block_source *)b)->fd = 0; + } + + reftable_free(b); +} + +static int file_read_block(void *v, struct reftable_block *dest, uint64_t off, + uint32_t size) +{ + struct file_block_source *b = (struct file_block_source *)v; + assert(off + size <= b->size); + dest->data = reftable_malloc(size); + if (pread(b->fd, dest->data, size, off) != size) + return -1; + dest->len = size; + return size; +} + +struct reftable_block_source_vtable file_vtable = { + .size = &file_size, + .read_block = &file_read_block, + .return_block = &file_return_block, + .close = &file_close, +}; + +int reftable_block_source_from_file(struct reftable_block_source *bs, + const char *name) +{ + struct stat st = { 0 }; + int err = 0; + int fd = open(name, O_RDONLY); + struct file_block_source *p = NULL; + if (fd < 0) { + if (errno == ENOENT) { + return REFTABLE_NOT_EXIST_ERROR; + } + return -1; + } + + err = fstat(fd, &st); + if (err < 0) + return -1; + + p = reftable_calloc(sizeof(struct file_block_source)); + p->size = st.st_size; + p->fd = fd; + + assert(bs->ops == NULL); + bs->ops = &file_vtable; + bs->arg = p; + return 0; +} + +int reftable_fd_write(void *arg, const void *data, size_t sz) +{ + int *fdp = (int *)arg; + return write(*fdp, data, sz); +} diff --git a/reftable/iter.c b/reftable/iter.c new file mode 100644 index 00000000000..8914e09ac07 --- /dev/null +++ b/reftable/iter.c @@ -0,0 +1,242 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "iter.h" + +#include "system.h" + +#include "block.h" +#include "constants.h" +#include "reader.h" +#include "reftable.h" + +bool iterator_is_null(struct reftable_iterator *it) +{ + return it->ops == NULL; +} + +static int empty_iterator_next(void *arg, struct reftable_record *rec) +{ + return 1; +} + +static void empty_iterator_close(void *arg) +{ +} + +struct reftable_iterator_vtable empty_vtable = { + .next = &empty_iterator_next, + .close = &empty_iterator_close, +}; + +void iterator_set_empty(struct reftable_iterator *it) +{ + assert(it->ops == NULL); + it->iter_arg = NULL; + it->ops = &empty_vtable; +} + +int iterator_next(struct reftable_iterator *it, struct reftable_record *rec) +{ + return it->ops->next(it->iter_arg, rec); +} + +void reftable_iterator_destroy(struct reftable_iterator *it) +{ + if (it->ops == NULL) { + return; + } + it->ops->close(it->iter_arg); + it->ops = NULL; + FREE_AND_NULL(it->iter_arg); +} + +int reftable_iterator_next_ref(struct reftable_iterator *it, + struct reftable_ref_record *ref) +{ + struct reftable_record rec = { 0 }; + reftable_record_from_ref(&rec, ref); + return iterator_next(it, &rec); +} + +int reftable_iterator_next_log(struct reftable_iterator *it, + struct reftable_log_record *log) +{ + struct reftable_record rec = { 0 }; + reftable_record_from_log(&rec, log); + return iterator_next(it, &rec); +} + +static void filtering_ref_iterator_close(void *iter_arg) +{ + struct filtering_ref_iterator *fri = + (struct filtering_ref_iterator *)iter_arg; + strbuf_release(&fri->oid); + reftable_iterator_destroy(&fri->it); +} + +static int filtering_ref_iterator_next(void *iter_arg, + struct reftable_record *rec) +{ + struct filtering_ref_iterator *fri = + (struct filtering_ref_iterator *)iter_arg; + struct reftable_ref_record *ref = + (struct reftable_ref_record *)rec->data; + int err = 0; + while (true) { + err = reftable_iterator_next_ref(&fri->it, ref); + if (err != 0) { + break; + } + + if (fri->double_check) { + struct reftable_iterator it = { 0 }; + + err = reftable_table_seek_ref(&fri->tab, &it, + ref->ref_name); + if (err == 0) { + err = reftable_iterator_next_ref(&it, ref); + } + + reftable_iterator_destroy(&it); + + if (err < 0) { + break; + } + + if (err > 0) { + continue; + } + } + + if ((ref->target_value != NULL && + !memcmp(fri->oid.buf, ref->target_value, fri->oid.len)) || + (ref->value != NULL && + !memcmp(fri->oid.buf, ref->value, fri->oid.len))) { + return 0; + } + } + + reftable_ref_record_clear(ref); + return err; +} + +struct reftable_iterator_vtable filtering_ref_iterator_vtable = { + .next = &filtering_ref_iterator_next, + .close = &filtering_ref_iterator_close, +}; + +void iterator_from_filtering_ref_iterator(struct reftable_iterator *it, + struct filtering_ref_iterator *fri) +{ + assert(it->ops == NULL); + it->iter_arg = fri; + it->ops = &filtering_ref_iterator_vtable; +} + +static void indexed_table_ref_iter_close(void *p) +{ + struct indexed_table_ref_iter *it = (struct indexed_table_ref_iter *)p; + block_iter_close(&it->cur); + reftable_block_done(&it->block_reader.block); + strbuf_release(&it->oid); +} + +static int indexed_table_ref_iter_next_block(struct indexed_table_ref_iter *it) +{ + uint64_t off; + int err = 0; + if (it->offset_idx == it->offset_len) { + it->finished = true; + return 1; + } + + reftable_block_done(&it->block_reader.block); + + off = it->offsets[it->offset_idx++]; + err = reader_init_block_reader(it->r, &it->block_reader, off, + BLOCK_TYPE_REF); + if (err < 0) { + return err; + } + if (err > 0) { + /* indexed block does not exist. */ + return REFTABLE_FORMAT_ERROR; + } + block_reader_start(&it->block_reader, &it->cur); + return 0; +} + +static int indexed_table_ref_iter_next(void *p, struct reftable_record *rec) +{ + struct indexed_table_ref_iter *it = (struct indexed_table_ref_iter *)p; + struct reftable_ref_record *ref = + (struct reftable_ref_record *)rec->data; + + while (true) { + int err = block_iter_next(&it->cur, rec); + if (err < 0) { + return err; + } + + if (err > 0) { + err = indexed_table_ref_iter_next_block(it); + if (err < 0) { + return err; + } + + if (it->finished) { + return 1; + } + continue; + } + + if (!memcmp(it->oid.buf, ref->target_value, it->oid.len) || + !memcmp(it->oid.buf, ref->value, it->oid.len)) { + return 0; + } + } +} + +int new_indexed_table_ref_iter(struct indexed_table_ref_iter **dest, + struct reftable_reader *r, uint8_t *oid, + int oid_len, uint64_t *offsets, int offset_len) +{ + struct indexed_table_ref_iter empty = INDEXED_TABLE_REF_ITER_INIT; + struct indexed_table_ref_iter *itr = + reftable_calloc(sizeof(struct indexed_table_ref_iter)); + int err = 0; + + *itr = empty; + itr->r = r; + strbuf_add(&itr->oid, oid, oid_len); + + itr->offsets = offsets; + itr->offset_len = offset_len; + + err = indexed_table_ref_iter_next_block(itr); + if (err < 0) { + reftable_free(itr); + } else { + *dest = itr; + } + return err; +} + +struct reftable_iterator_vtable indexed_table_ref_iter_vtable = { + .next = &indexed_table_ref_iter_next, + .close = &indexed_table_ref_iter_close, +}; + +void iterator_from_indexed_table_ref_iter(struct reftable_iterator *it, + struct indexed_table_ref_iter *itr) +{ + assert(it->ops == NULL); + it->iter_arg = itr; + it->ops = &indexed_table_ref_iter_vtable; +} diff --git a/reftable/iter.h b/reftable/iter.h new file mode 100644 index 00000000000..c96aaed5839 --- /dev/null +++ b/reftable/iter.h @@ -0,0 +1,72 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef ITER_H +#define ITER_H + +#include "block.h" +#include "record.h" +#include "strbuf.h" + +struct reftable_iterator_vtable { + int (*next)(void *iter_arg, struct reftable_record *rec); + void (*close)(void *iter_arg); +}; + +void iterator_set_empty(struct reftable_iterator *it); +int iterator_next(struct reftable_iterator *it, struct reftable_record *rec); + +/* Returns true for a zeroed out iterator, such as the one returned from + iterator_destroy. */ +bool iterator_is_null(struct reftable_iterator *it); + +/* iterator that produces only ref records that point to `oid` */ +struct filtering_ref_iterator { + bool double_check; + struct reftable_table tab; + struct strbuf oid; + struct reftable_iterator it; +}; +#define FILTERING_REF_ITERATOR_INIT \ + { \ + .oid = STRBUF_INIT \ + } + +void iterator_from_filtering_ref_iterator(struct reftable_iterator *, + struct filtering_ref_iterator *); + +/* iterator that produces only ref records that point to `oid`, + but using the object index. + */ +struct indexed_table_ref_iter { + struct reftable_reader *r; + struct strbuf oid; + + /* mutable */ + uint64_t *offsets; + + /* Points to the next offset to read. */ + int offset_idx; + int offset_len; + struct block_reader block_reader; + struct block_iter cur; + bool finished; +}; + +#define INDEXED_TABLE_REF_ITER_INIT \ + { \ + .cur = { .last_key = STRBUF_INIT }, .oid = STRBUF_INIT, \ + } + +void iterator_from_indexed_table_ref_iter(struct reftable_iterator *it, + struct indexed_table_ref_iter *itr); +int new_indexed_table_ref_iter(struct indexed_table_ref_iter **dest, + struct reftable_reader *r, uint8_t *oid, + int oid_len, uint64_t *offsets, int offset_len); + +#endif diff --git a/reftable/merged.c b/reftable/merged.c new file mode 100644 index 00000000000..9ca4fd42c11 --- /dev/null +++ b/reftable/merged.c @@ -0,0 +1,321 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "merged.h" + +#include "system.h" + +#include "constants.h" +#include "iter.h" +#include "pq.h" +#include "reader.h" +#include "record.h" + +static int merged_iter_init(struct merged_iter *mi) +{ + int i = 0; + for (i = 0; i < mi->stack_len; i++) { + struct reftable_record rec = reftable_new_record(mi->typ); + int err = iterator_next(&mi->stack[i], &rec); + if (err < 0) { + return err; + } + + if (err > 0) { + reftable_iterator_destroy(&mi->stack[i]); + reftable_record_destroy(&rec); + } else { + struct pq_entry e = { + .rec = rec, + .index = i, + }; + merged_iter_pqueue_add(&mi->pq, e); + } + } + + return 0; +} + +static void merged_iter_close(void *p) +{ + struct merged_iter *mi = (struct merged_iter *)p; + int i = 0; + merged_iter_pqueue_clear(&mi->pq); + for (i = 0; i < mi->stack_len; i++) { + reftable_iterator_destroy(&mi->stack[i]); + } + reftable_free(mi->stack); +} + +static int merged_iter_advance_nonnull_subiter(struct merged_iter *mi, + size_t idx) +{ + struct reftable_record rec = reftable_new_record(mi->typ); + struct pq_entry e = { + .rec = rec, + .index = idx, + }; + int err = iterator_next(&mi->stack[idx], &rec); + if (err < 0) + return err; + + if (err > 0) { + reftable_iterator_destroy(&mi->stack[idx]); + reftable_record_destroy(&rec); + return 0; + } + + merged_iter_pqueue_add(&mi->pq, e); + return 0; +} + +static int merged_iter_advance_subiter(struct merged_iter *mi, size_t idx) +{ + if (iterator_is_null(&mi->stack[idx])) + return 0; + return merged_iter_advance_nonnull_subiter(mi, idx); +} + +static int merged_iter_next_entry(struct merged_iter *mi, + struct reftable_record *rec) +{ + struct strbuf entry_key = STRBUF_INIT; + struct pq_entry entry = { 0 }; + int err = 0; + + if (merged_iter_pqueue_is_empty(mi->pq)) + return 1; + + entry = merged_iter_pqueue_remove(&mi->pq); + err = merged_iter_advance_subiter(mi, entry.index); + if (err < 0) + return err; + + /* + One can also use reftable as datacenter-local storage, where the ref + database is maintained in globally consistent database (eg. + CockroachDB or Spanner). In this scenario, replication delays together + with compaction may cause newer tables to contain older entries. In + such a deployment, the loop below must be changed to collect all + entries for the same key, and return new the newest one. + */ + reftable_record_key(&entry.rec, &entry_key); + while (!merged_iter_pqueue_is_empty(mi->pq)) { + struct pq_entry top = merged_iter_pqueue_top(mi->pq); + struct strbuf k = STRBUF_INIT; + int err = 0, cmp = 0; + + reftable_record_key(&top.rec, &k); + + cmp = strbuf_cmp(&k, &entry_key); + strbuf_release(&k); + + if (cmp > 0) { + break; + } + + merged_iter_pqueue_remove(&mi->pq); + err = merged_iter_advance_subiter(mi, top.index); + if (err < 0) { + return err; + } + reftable_record_destroy(&top.rec); + } + + reftable_record_copy_from(rec, &entry.rec, hash_size(mi->hash_id)); + reftable_record_destroy(&entry.rec); + strbuf_release(&entry_key); + return 0; +} + +static int merged_iter_next(struct merged_iter *mi, struct reftable_record *rec) +{ + while (true) { + int err = merged_iter_next_entry(mi, rec); + if (err == 0 && mi->suppress_deletions && + reftable_record_is_deletion(rec)) { + continue; + } + + return err; + } +} + +static int merged_iter_next_void(void *p, struct reftable_record *rec) +{ + struct merged_iter *mi = (struct merged_iter *)p; + if (merged_iter_pqueue_is_empty(mi->pq)) + return 1; + + return merged_iter_next(mi, rec); +} + +struct reftable_iterator_vtable merged_iter_vtable = { + .next = &merged_iter_next_void, + .close = &merged_iter_close, +}; + +static void iterator_from_merged_iter(struct reftable_iterator *it, + struct merged_iter *mi) +{ + assert(it->ops == NULL); + it->iter_arg = mi; + it->ops = &merged_iter_vtable; +} + +int reftable_new_merged_table(struct reftable_merged_table **dest, + struct reftable_reader **stack, int n, + uint32_t hash_id) +{ + struct reftable_merged_table *m = NULL; + uint64_t last_max = 0; + uint64_t first_min = 0; + int i = 0; + for (i = 0; i < n; i++) { + struct reftable_reader *r = stack[i]; + if (r->hash_id != hash_id) { + return REFTABLE_FORMAT_ERROR; + } + if (i > 0 && last_max >= reftable_reader_min_update_index(r)) { + return REFTABLE_FORMAT_ERROR; + } + if (i == 0) { + first_min = reftable_reader_min_update_index(r); + } + + last_max = reftable_reader_max_update_index(r); + } + + m = (struct reftable_merged_table *)reftable_calloc( + sizeof(struct reftable_merged_table)); + m->stack = stack; + m->stack_len = n; + m->min = first_min; + m->max = last_max; + m->hash_id = hash_id; + *dest = m; + return 0; +} + +void reftable_merged_table_close(struct reftable_merged_table *mt) +{ + int i = 0; + for (i = 0; i < mt->stack_len; i++) { + reftable_reader_free(mt->stack[i]); + } + FREE_AND_NULL(mt->stack); + mt->stack_len = 0; +} + +/* clears the list of subtable, without affecting the readers themselves. */ +void merged_table_clear(struct reftable_merged_table *mt) +{ + FREE_AND_NULL(mt->stack); + mt->stack_len = 0; +} + +void reftable_merged_table_free(struct reftable_merged_table *mt) +{ + if (mt == NULL) { + return; + } + merged_table_clear(mt); + reftable_free(mt); +} + +uint64_t +reftable_merged_table_max_update_index(struct reftable_merged_table *mt) +{ + return mt->max; +} + +uint64_t +reftable_merged_table_min_update_index(struct reftable_merged_table *mt) +{ + return mt->min; +} + +int merged_table_seek_record(struct reftable_merged_table *mt, + struct reftable_iterator *it, + struct reftable_record *rec) +{ + struct reftable_iterator *iters = reftable_calloc( + sizeof(struct reftable_iterator) * mt->stack_len); + struct merged_iter merged = { + .stack = iters, + .typ = reftable_record_type(rec), + .hash_id = mt->hash_id, + .suppress_deletions = mt->suppress_deletions, + }; + int n = 0; + int err = 0; + int i = 0; + for (i = 0; i < mt->stack_len && err == 0; i++) { + int e = reader_seek(mt->stack[i], &iters[n], rec); + if (e < 0) { + err = e; + } + if (e == 0) { + n++; + } + } + if (err < 0) { + int i = 0; + for (i = 0; i < n; i++) { + reftable_iterator_destroy(&iters[i]); + } + reftable_free(iters); + return err; + } + + merged.stack_len = n; + err = merged_iter_init(&merged); + if (err < 0) { + merged_iter_close(&merged); + return err; + } else { + struct merged_iter *p = + reftable_malloc(sizeof(struct merged_iter)); + *p = merged; + iterator_from_merged_iter(it, p); + } + return 0; +} + +int reftable_merged_table_seek_ref(struct reftable_merged_table *mt, + struct reftable_iterator *it, + const char *name) +{ + struct reftable_ref_record ref = { + .ref_name = (char *)name, + }; + struct reftable_record rec = { 0 }; + reftable_record_from_ref(&rec, &ref); + return merged_table_seek_record(mt, it, &rec); +} + +int reftable_merged_table_seek_log_at(struct reftable_merged_table *mt, + struct reftable_iterator *it, + const char *name, uint64_t update_index) +{ + struct reftable_log_record log = { + .ref_name = (char *)name, + .update_index = update_index, + }; + struct reftable_record rec = { 0 }; + reftable_record_from_log(&rec, &log); + return merged_table_seek_record(mt, it, &rec); +} + +int reftable_merged_table_seek_log(struct reftable_merged_table *mt, + struct reftable_iterator *it, + const char *name) +{ + uint64_t max = ~((uint64_t)0); + return reftable_merged_table_seek_log_at(mt, it, name, max); +} diff --git a/reftable/merged.h b/reftable/merged.h new file mode 100644 index 00000000000..fe80556c1dc --- /dev/null +++ b/reftable/merged.h @@ -0,0 +1,39 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef MERGED_H +#define MERGED_H + +#include "pq.h" +#include "reftable.h" + +struct reftable_merged_table { + struct reftable_reader **stack; + int stack_len; + uint32_t hash_id; + bool suppress_deletions; + + uint64_t min; + uint64_t max; +}; + +struct merged_iter { + struct reftable_iterator *stack; + uint32_t hash_id; + int stack_len; + uint8_t typ; + bool suppress_deletions; + struct merged_iter_pqueue pq; +}; + +void merged_table_clear(struct reftable_merged_table *mt); +int merged_table_seek_record(struct reftable_merged_table *mt, + struct reftable_iterator *it, + struct reftable_record *rec); + +#endif diff --git a/reftable/merged_test.c b/reftable/merged_test.c new file mode 100644 index 00000000000..6f696918bbe --- /dev/null +++ b/reftable/merged_test.c @@ -0,0 +1,273 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "merged.h" + +#include "system.h" + +#include "basics.h" +#include "block.h" +#include "constants.h" +#include "pq.h" +#include "reader.h" +#include "record.h" +#include "reftable.h" +#include "test_framework.h" +#include "reftable-tests.h" + +static void test_pq(void) +{ + char *names[54] = { 0 }; + int N = ARRAY_SIZE(names) - 1; + + struct merged_iter_pqueue pq = { 0 }; + const char *last = NULL; + + int i = 0; + for (i = 0; i < N; i++) { + char name[100]; + snprintf(name, sizeof(name), "%02d", i); + names[i] = xstrdup(name); + } + + i = 1; + do { + struct reftable_record rec = + reftable_new_record(BLOCK_TYPE_REF); + struct pq_entry e = { 0 }; + + reftable_record_as_ref(&rec)->ref_name = names[i]; + e.rec = rec; + merged_iter_pqueue_add(&pq, e); + merged_iter_pqueue_check(pq); + i = (i * 7) % N; + } while (i != 1); + + while (!merged_iter_pqueue_is_empty(pq)) { + struct pq_entry e = merged_iter_pqueue_remove(&pq); + struct reftable_ref_record *ref = + reftable_record_as_ref(&e.rec); + + merged_iter_pqueue_check(pq); + + if (last != NULL) { + assert(strcmp(last, ref->ref_name) < 0); + } + last = ref->ref_name; + ref->ref_name = NULL; + reftable_free(ref); + } + + for (i = 0; i < N; i++) { + reftable_free(names[i]); + } + + merged_iter_pqueue_clear(&pq); +} + +static void write_test_table(struct strbuf *buf, + struct reftable_ref_record refs[], int n) +{ + int min = 0xffffffff; + int max = 0; + int i = 0; + int err; + + struct reftable_write_options opts = { + .block_size = 256, + }; + struct reftable_writer *w = NULL; + for (i = 0; i < n; i++) { + uint64_t ui = refs[i].update_index; + if (ui > max) { + max = ui; + } + if (ui < min) { + min = ui; + } + } + + w = reftable_new_writer(&strbuf_add_void, buf, &opts); + reftable_writer_set_limits(w, min, max); + + for (i = 0; i < n; i++) { + uint64_t before = refs[i].update_index; + int n = reftable_writer_add_ref(w, &refs[i]); + assert(n == 0); + assert(before == refs[i].update_index); + } + + err = reftable_writer_close(w); + assert_err(err); + + reftable_writer_free(w); +} + +static struct reftable_merged_table * +merged_table_from_records(struct reftable_ref_record **refs, + struct reftable_block_source **source, int *sizes, + struct strbuf *buf, int n) +{ + struct reftable_reader **rd = reftable_calloc(n * sizeof(*rd)); + int i = 0; + struct reftable_merged_table *mt = NULL; + int err; + *source = reftable_calloc(n * sizeof(**source)); + for (i = 0; i < n; i++) { + write_test_table(&buf[i], refs[i], sizes[i]); + block_source_from_strbuf(&(*source)[i], &buf[i]); + + err = reftable_new_reader(&rd[i], &(*source)[i], "name"); + assert_err(err); + } + + err = reftable_new_merged_table(&mt, rd, n, SHA1_ID); + assert_err(err); + return mt; +} + +static void test_merged_between(void) +{ + uint8_t hash1[SHA1_SIZE] = { 1, 2, 3, 0 }; + + struct reftable_ref_record r1[] = { { + .ref_name = "b", + .update_index = 1, + .value = hash1, + } }; + struct reftable_ref_record r2[] = { { + .ref_name = "a", + .update_index = 2, + } }; + + struct reftable_ref_record *refs[] = { r1, r2 }; + int sizes[] = { 1, 1 }; + struct strbuf bufs[2] = { STRBUF_INIT, STRBUF_INIT }; + struct reftable_block_source *bs = NULL; + struct reftable_merged_table *mt = + merged_table_from_records(refs, &bs, sizes, bufs, 2); + int i; + struct reftable_ref_record ref = { 0 }; + struct reftable_iterator it = { 0 }; + int err = reftable_merged_table_seek_ref(mt, &it, "a"); + assert_err(err); + + err = reftable_iterator_next_ref(&it, &ref); + assert_err(err); + assert(ref.update_index == 2); + reftable_ref_record_clear(&ref); + + reftable_iterator_destroy(&it); + reftable_merged_table_close(mt); + reftable_merged_table_free(mt); + for (i = 0; i < ARRAY_SIZE(bufs); i++) { + strbuf_release(&bufs[i]); + } + reftable_free(bs); +} + +static void test_merged(void) +{ + uint8_t hash1[SHA1_SIZE] = { 1 }; + uint8_t hash2[SHA1_SIZE] = { 2 }; + struct reftable_ref_record r1[] = { { + .ref_name = "a", + .update_index = 1, + .value = hash1, + }, + { + .ref_name = "b", + .update_index = 1, + .value = hash1, + }, + { + .ref_name = "c", + .update_index = 1, + .value = hash1, + } }; + struct reftable_ref_record r2[] = { { + .ref_name = "a", + .update_index = 2, + } }; + struct reftable_ref_record r3[] = { + { + .ref_name = "c", + .update_index = 3, + .value = hash2, + }, + { + .ref_name = "d", + .update_index = 3, + .value = hash1, + }, + }; + + struct reftable_ref_record want[] = { + r2[0], + r1[1], + r3[0], + r3[1], + }; + + struct reftable_ref_record *refs[] = { r1, r2, r3 }; + int sizes[3] = { 3, 1, 2 }; + struct strbuf bufs[3] = { STRBUF_INIT, STRBUF_INIT, STRBUF_INIT }; + struct reftable_block_source *bs = NULL; + + struct reftable_merged_table *mt = + merged_table_from_records(refs, &bs, sizes, bufs, 3); + + struct reftable_iterator it = { 0 }; + int err = reftable_merged_table_seek_ref(mt, &it, "a"); + struct reftable_ref_record *out = NULL; + int len = 0; + int cap = 0; + int i = 0; + + assert_err(err); + while (len < 100) { /* cap loops/recursion. */ + struct reftable_ref_record ref = { 0 }; + int err = reftable_iterator_next_ref(&it, &ref); + if (err > 0) { + break; + } + if (len == cap) { + cap = 2 * cap + 1; + out = reftable_realloc( + out, sizeof(struct reftable_ref_record) * cap); + } + out[len++] = ref; + } + reftable_iterator_destroy(&it); + + assert(ARRAY_SIZE(want) == len); + for (i = 0; i < len; i++) { + assert(reftable_ref_record_equal(&want[i], &out[i], SHA1_SIZE)); + } + for (i = 0; i < len; i++) { + reftable_ref_record_clear(&out[i]); + } + reftable_free(out); + + for (i = 0; i < 3; i++) { + strbuf_release(&bufs[i]); + } + reftable_merged_table_close(mt); + reftable_merged_table_free(mt); + reftable_free(bs); +} + +/* XXX test refs_for(oid) */ + +int merged_test_main(int argc, const char *argv[]) +{ + add_test_case("test_merged_between", &test_merged_between); + add_test_case("test_pq", &test_pq); + add_test_case("test_merged", &test_merged); + return test_main(argc, argv); +} diff --git a/reftable/pq.c b/reftable/pq.c new file mode 100644 index 00000000000..de7ed658a42 --- /dev/null +++ b/reftable/pq.c @@ -0,0 +1,115 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "pq.h" + +#include "reftable.h" +#include "system.h" +#include "basics.h" + +int pq_less(struct pq_entry a, struct pq_entry b) +{ + struct strbuf ak = STRBUF_INIT; + struct strbuf bk = STRBUF_INIT; + int cmp = 0; + reftable_record_key(&a.rec, &ak); + reftable_record_key(&b.rec, &bk); + + cmp = strbuf_cmp(&ak, &bk); + + strbuf_release(&ak); + strbuf_release(&bk); + + if (cmp == 0) + return a.index > b.index; + + return cmp < 0; +} + +struct pq_entry merged_iter_pqueue_top(struct merged_iter_pqueue pq) +{ + return pq.heap[0]; +} + +bool merged_iter_pqueue_is_empty(struct merged_iter_pqueue pq) +{ + return pq.len == 0; +} + +void merged_iter_pqueue_check(struct merged_iter_pqueue pq) +{ + int i = 0; + for (i = 1; i < pq.len; i++) { + int parent = (i - 1) / 2; + + assert(pq_less(pq.heap[parent], pq.heap[i])); + } +} + +struct pq_entry merged_iter_pqueue_remove(struct merged_iter_pqueue *pq) +{ + int i = 0; + struct pq_entry e = pq->heap[0]; + pq->heap[0] = pq->heap[pq->len - 1]; + pq->len--; + + i = 0; + while (i < pq->len) { + int min = i; + int j = 2 * i + 1; + int k = 2 * i + 2; + if (j < pq->len && pq_less(pq->heap[j], pq->heap[i])) { + min = j; + } + if (k < pq->len && pq_less(pq->heap[k], pq->heap[min])) { + min = k; + } + + if (min == i) { + break; + } + + SWAP(pq->heap[i], pq->heap[min]); + i = min; + } + + return e; +} + +void merged_iter_pqueue_add(struct merged_iter_pqueue *pq, struct pq_entry e) +{ + int i = 0; + if (pq->len == pq->cap) { + pq->cap = 2 * pq->cap + 1; + pq->heap = reftable_realloc(pq->heap, + pq->cap * sizeof(struct pq_entry)); + } + + pq->heap[pq->len++] = e; + i = pq->len - 1; + while (i > 0) { + int j = (i - 1) / 2; + if (pq_less(pq->heap[j], pq->heap[i])) { + break; + } + + SWAP(pq->heap[j], pq->heap[i]); + + i = j; + } +} + +void merged_iter_pqueue_clear(struct merged_iter_pqueue *pq) +{ + int i = 0; + for (i = 0; i < pq->len; i++) { + reftable_record_destroy(&pq->heap[i].rec); + } + FREE_AND_NULL(pq->heap); + pq->len = pq->cap = 0; +} diff --git a/reftable/pq.h b/reftable/pq.h new file mode 100644 index 00000000000..43c0974f162 --- /dev/null +++ b/reftable/pq.h @@ -0,0 +1,34 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef PQ_H +#define PQ_H + +#include "record.h" + +struct pq_entry { + int index; + struct reftable_record rec; +}; + +int pq_less(struct pq_entry a, struct pq_entry b); + +struct merged_iter_pqueue { + struct pq_entry *heap; + int len; + int cap; +}; + +struct pq_entry merged_iter_pqueue_top(struct merged_iter_pqueue pq); +bool merged_iter_pqueue_is_empty(struct merged_iter_pqueue pq); +void merged_iter_pqueue_check(struct merged_iter_pqueue pq); +struct pq_entry merged_iter_pqueue_remove(struct merged_iter_pqueue *pq); +void merged_iter_pqueue_add(struct merged_iter_pqueue *pq, struct pq_entry e); +void merged_iter_pqueue_clear(struct merged_iter_pqueue *pq); + +#endif diff --git a/reftable/reader.c b/reftable/reader.c new file mode 100644 index 00000000000..3c8854c12d9 --- /dev/null +++ b/reftable/reader.c @@ -0,0 +1,744 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "reader.h" + +#include "system.h" +#include "block.h" +#include "constants.h" +#include "iter.h" +#include "record.h" +#include "reftable.h" +#include "tree.h" + +uint64_t block_source_size(struct reftable_block_source *source) +{ + return source->ops->size(source->arg); +} + +int block_source_read_block(struct reftable_block_source *source, + struct reftable_block *dest, uint64_t off, + uint32_t size) +{ + int result = source->ops->read_block(source->arg, dest, off, size); + dest->source = *source; + return result; +} + +void reftable_block_done(struct reftable_block *blockp) +{ + struct reftable_block_source source = blockp->source; + if (blockp != NULL && source.ops != NULL) + source.ops->return_block(source.arg, blockp); + blockp->data = NULL; + blockp->len = 0; + blockp->source.ops = NULL; + blockp->source.arg = NULL; +} + +void block_source_close(struct reftable_block_source *source) +{ + if (source->ops == NULL) { + return; + } + + source->ops->close(source->arg); + source->ops = NULL; +} + +static struct reftable_reader_offsets * +reader_offsets_for(struct reftable_reader *r, uint8_t typ) +{ + switch (typ) { + case BLOCK_TYPE_REF: + return &r->ref_offsets; + case BLOCK_TYPE_LOG: + return &r->log_offsets; + case BLOCK_TYPE_OBJ: + return &r->obj_offsets; + } + abort(); +} + +static int reader_get_block(struct reftable_reader *r, + struct reftable_block *dest, uint64_t off, + uint32_t sz) +{ + if (off >= r->size) + return 0; + + if (off + sz > r->size) { + sz = r->size - off; + } + + return block_source_read_block(&r->source, dest, off, sz); +} + +uint32_t reftable_reader_hash_id(struct reftable_reader *r) +{ + return r->hash_id; +} + +const char *reader_name(struct reftable_reader *r) +{ + return r->name; +} + +static int parse_footer(struct reftable_reader *r, uint8_t *footer, + uint8_t *header) +{ + uint8_t *f = footer; + uint8_t first_block_typ; + int err = 0; + uint32_t computed_crc; + uint32_t file_crc; + + if (memcmp(f, "REFT", 4)) { + err = REFTABLE_FORMAT_ERROR; + goto done; + } + f += 4; + + if (memcmp(footer, header, header_size(r->version))) { + err = REFTABLE_FORMAT_ERROR; + goto done; + } + + f++; + r->block_size = get_be24(f); + + f += 3; + r->min_update_index = get_be64(f); + f += 8; + r->max_update_index = get_be64(f); + f += 8; + + if (r->version == 1) { + r->hash_id = SHA1_ID; + } else { + r->hash_id = get_be32(f); + switch (r->hash_id) { + case SHA1_ID: + break; + case SHA256_ID: + break; + default: + err = REFTABLE_FORMAT_ERROR; + goto done; + } + f += 4; + } + + r->ref_offsets.index_offset = get_be64(f); + f += 8; + + r->obj_offsets.offset = get_be64(f); + f += 8; + + r->object_id_len = r->obj_offsets.offset & ((1 << 5) - 1); + r->obj_offsets.offset >>= 5; + + r->obj_offsets.index_offset = get_be64(f); + f += 8; + r->log_offsets.offset = get_be64(f); + f += 8; + r->log_offsets.index_offset = get_be64(f); + f += 8; + + computed_crc = crc32(0, footer, f - footer); + file_crc = get_be32(f); + f += 4; + if (computed_crc != file_crc) { + err = REFTABLE_FORMAT_ERROR; + goto done; + } + + first_block_typ = header[header_size(r->version)]; + r->ref_offsets.present = (first_block_typ == BLOCK_TYPE_REF); + r->ref_offsets.offset = 0; + r->log_offsets.present = (first_block_typ == BLOCK_TYPE_LOG || + r->log_offsets.offset > 0); + r->obj_offsets.present = r->obj_offsets.offset > 0; + err = 0; +done: + return err; +} + +int init_reader(struct reftable_reader *r, struct reftable_block_source *source, + const char *name) +{ + struct reftable_block footer = { 0 }; + struct reftable_block header = { 0 }; + int err = 0; + + memset(r, 0, sizeof(struct reftable_reader)); + + /* Need +1 to read type of first block. */ + err = block_source_read_block(source, &header, 0, header_size(2) + 1); + if (err != header_size(2) + 1) { + err = REFTABLE_IO_ERROR; + goto done; + } + + if (memcmp(header.data, "REFT", 4)) { + err = REFTABLE_FORMAT_ERROR; + goto done; + } + r->version = header.data[4]; + if (r->version != 1 && r->version != 2) { + err = REFTABLE_FORMAT_ERROR; + goto done; + } + + r->size = block_source_size(source) - footer_size(r->version); + r->source = *source; + r->name = xstrdup(name); + r->hash_id = 0; + + err = block_source_read_block(source, &footer, r->size, + footer_size(r->version)); + if (err != footer_size(r->version)) { + err = REFTABLE_IO_ERROR; + goto done; + } + + err = parse_footer(r, footer.data, header.data); +done: + reftable_block_done(&footer); + reftable_block_done(&header); + return err; +} + +struct table_iter { + struct reftable_reader *r; + uint8_t typ; + uint64_t block_off; + struct block_iter bi; + bool finished; +}; +#define TABLE_ITER_INIT \ + { \ + .bi = {.last_key = STRBUF_INIT } \ + } + +static void table_iter_copy_from(struct table_iter *dest, + struct table_iter *src) +{ + dest->r = src->r; + dest->typ = src->typ; + dest->block_off = src->block_off; + dest->finished = src->finished; + block_iter_copy_from(&dest->bi, &src->bi); +} + +static int table_iter_next_in_block(struct table_iter *ti, + struct reftable_record *rec) +{ + int res = block_iter_next(&ti->bi, rec); + if (res == 0 && reftable_record_type(rec) == BLOCK_TYPE_REF) { + ((struct reftable_ref_record *)rec->data)->update_index += + ti->r->min_update_index; + } + + return res; +} + +static void table_iter_block_done(struct table_iter *ti) +{ + if (ti->bi.br == NULL) { + return; + } + reftable_block_done(&ti->bi.br->block); + FREE_AND_NULL(ti->bi.br); + + ti->bi.last_key.len = 0; + ti->bi.next_off = 0; +} + +static int32_t extract_block_size(uint8_t *data, uint8_t *typ, uint64_t off, + int version) +{ + int32_t result = 0; + + if (off == 0) { + data += header_size(version); + } + + *typ = data[0]; + if (reftable_is_block_type(*typ)) { + result = get_be24(data + 1); + } + return result; +} + +int reader_init_block_reader(struct reftable_reader *r, struct block_reader *br, + uint64_t next_off, uint8_t want_typ) +{ + int32_t guess_block_size = r->block_size ? r->block_size : + DEFAULT_BLOCK_SIZE; + struct reftable_block block = { 0 }; + uint8_t block_typ = 0; + int err = 0; + uint32_t header_off = next_off ? 0 : header_size(r->version); + int32_t block_size = 0; + + if (next_off >= r->size) + return 1; + + err = reader_get_block(r, &block, next_off, guess_block_size); + if (err < 0) + return err; + + block_size = extract_block_size(block.data, &block_typ, next_off, + r->version); + if (block_size < 0) + return block_size; + + if (want_typ != BLOCK_TYPE_ANY && block_typ != want_typ) { + reftable_block_done(&block); + return 1; + } + + if (block_size > guess_block_size) { + reftable_block_done(&block); + err = reader_get_block(r, &block, next_off, block_size); + if (err < 0) { + return err; + } + } + + return block_reader_init(br, &block, header_off, r->block_size, + hash_size(r->hash_id)); +} + +static int table_iter_next_block(struct table_iter *dest, + struct table_iter *src) +{ + uint64_t next_block_off = src->block_off + src->bi.br->full_block_size; + struct block_reader br = { 0 }; + int err = 0; + + dest->r = src->r; + dest->typ = src->typ; + dest->block_off = next_block_off; + + err = reader_init_block_reader(src->r, &br, next_block_off, src->typ); + if (err > 0) { + dest->finished = true; + return 1; + } + if (err != 0) + return err; + else { + struct block_reader *brp = + reftable_malloc(sizeof(struct block_reader)); + *brp = br; + + dest->finished = false; + block_reader_start(brp, &dest->bi); + } + return 0; +} + +static int table_iter_next(struct table_iter *ti, struct reftable_record *rec) +{ + if (reftable_record_type(rec) != ti->typ) + return REFTABLE_API_ERROR; + + while (true) { + struct table_iter next = TABLE_ITER_INIT; + int err = 0; + if (ti->finished) { + return 1; + } + + err = table_iter_next_in_block(ti, rec); + if (err <= 0) { + return err; + } + + err = table_iter_next_block(&next, ti); + if (err != 0) { + ti->finished = true; + } + table_iter_block_done(ti); + if (err != 0) { + return err; + } + table_iter_copy_from(ti, &next); + block_iter_close(&next.bi); + } +} + +static int table_iter_next_void(void *ti, struct reftable_record *rec) +{ + return table_iter_next((struct table_iter *)ti, rec); +} + +static void table_iter_close(void *p) +{ + struct table_iter *ti = (struct table_iter *)p; + table_iter_block_done(ti); + block_iter_close(&ti->bi); +} + +struct reftable_iterator_vtable table_iter_vtable = { + .next = &table_iter_next_void, + .close = &table_iter_close, +}; + +static void iterator_from_table_iter(struct reftable_iterator *it, + struct table_iter *ti) +{ + assert(it->ops == NULL); + it->iter_arg = ti; + it->ops = &table_iter_vtable; +} + +static int reader_table_iter_at(struct reftable_reader *r, + struct table_iter *ti, uint64_t off, + uint8_t typ) +{ + struct block_reader br = { 0 }; + struct block_reader *brp = NULL; + + int err = reader_init_block_reader(r, &br, off, typ); + if (err != 0) + return err; + + brp = reftable_malloc(sizeof(struct block_reader)); + *brp = br; + ti->r = r; + ti->typ = block_reader_type(brp); + ti->block_off = off; + block_reader_start(brp, &ti->bi); + return 0; +} + +static int reader_start(struct reftable_reader *r, struct table_iter *ti, + uint8_t typ, bool index) +{ + struct reftable_reader_offsets *offs = reader_offsets_for(r, typ); + uint64_t off = offs->offset; + if (index) { + off = offs->index_offset; + if (off == 0) { + return 1; + } + typ = BLOCK_TYPE_INDEX; + } + + return reader_table_iter_at(r, ti, off, typ); +} + +static int reader_seek_linear(struct reftable_reader *r, struct table_iter *ti, + struct reftable_record *want) +{ + struct reftable_record rec = + reftable_new_record(reftable_record_type(want)); + struct strbuf want_key = STRBUF_INIT; + struct strbuf got_key = STRBUF_INIT; + struct table_iter next = TABLE_ITER_INIT; + int err = -1; + + reftable_record_key(want, &want_key); + + while (true) { + err = table_iter_next_block(&next, ti); + if (err < 0) + goto done; + + if (err > 0) { + break; + } + + err = block_reader_first_key(next.bi.br, &got_key); + if (err < 0) + goto done; + + if (strbuf_cmp(&got_key, &want_key) > 0) { + table_iter_block_done(&next); + break; + } + + table_iter_block_done(ti); + table_iter_copy_from(ti, &next); + } + + err = block_iter_seek(&ti->bi, &want_key); + if (err < 0) + goto done; + err = 0; + +done: + block_iter_close(&next.bi); + reftable_record_destroy(&rec); + strbuf_release(&want_key); + strbuf_release(&got_key); + return err; +} + +static int reader_seek_indexed(struct reftable_reader *r, + struct reftable_iterator *it, + struct reftable_record *rec) +{ + struct reftable_index_record want_index = { .last_key = STRBUF_INIT }; + struct reftable_record want_index_rec = { 0 }; + struct reftable_index_record index_result = { .last_key = STRBUF_INIT }; + struct reftable_record index_result_rec = { 0 }; + struct table_iter index_iter = TABLE_ITER_INIT; + struct table_iter next = TABLE_ITER_INIT; + int err = 0; + + reftable_record_key(rec, &want_index.last_key); + reftable_record_from_index(&want_index_rec, &want_index); + reftable_record_from_index(&index_result_rec, &index_result); + + err = reader_start(r, &index_iter, reftable_record_type(rec), true); + if (err < 0) + goto done; + + err = reader_seek_linear(r, &index_iter, &want_index_rec); + while (true) { + err = table_iter_next(&index_iter, &index_result_rec); + table_iter_block_done(&index_iter); + if (err != 0) + goto done; + + err = reader_table_iter_at(r, &next, index_result.offset, 0); + if (err != 0) + goto done; + + err = block_iter_seek(&next.bi, &want_index.last_key); + if (err < 0) + goto done; + + if (next.typ == reftable_record_type(rec)) { + err = 0; + break; + } + + if (next.typ != BLOCK_TYPE_INDEX) { + err = REFTABLE_FORMAT_ERROR; + break; + } + + table_iter_copy_from(&index_iter, &next); + } + + if (err == 0) { + struct table_iter empty = TABLE_ITER_INIT; + struct table_iter *malloced = + reftable_calloc(sizeof(struct table_iter)); + *malloced = empty; + table_iter_copy_from(malloced, &next); + iterator_from_table_iter(it, malloced); + } +done: + block_iter_close(&next.bi); + table_iter_close(&index_iter); + reftable_record_clear(&want_index_rec); + reftable_record_clear(&index_result_rec); + return err; +} + +static int reader_seek_internal(struct reftable_reader *r, + struct reftable_iterator *it, + struct reftable_record *rec) +{ + struct reftable_reader_offsets *offs = + reader_offsets_for(r, reftable_record_type(rec)); + uint64_t idx = offs->index_offset; + struct table_iter ti = TABLE_ITER_INIT; + int err = 0; + if (idx > 0) + return reader_seek_indexed(r, it, rec); + + err = reader_start(r, &ti, reftable_record_type(rec), false); + if (err < 0) + return err; + err = reader_seek_linear(r, &ti, rec); + if (err < 0) + return err; + else { + struct table_iter *p = + reftable_malloc(sizeof(struct table_iter)); + *p = ti; + iterator_from_table_iter(it, p); + } + + return 0; +} + +int reader_seek(struct reftable_reader *r, struct reftable_iterator *it, + struct reftable_record *rec) +{ + uint8_t typ = reftable_record_type(rec); + + struct reftable_reader_offsets *offs = reader_offsets_for(r, typ); + if (!offs->present) { + iterator_set_empty(it); + return 0; + } + + return reader_seek_internal(r, it, rec); +} + +int reftable_reader_seek_ref(struct reftable_reader *r, + struct reftable_iterator *it, const char *name) +{ + struct reftable_ref_record ref = { + .ref_name = (char *)name, + }; + struct reftable_record rec = { 0 }; + reftable_record_from_ref(&rec, &ref); + return reader_seek(r, it, &rec); +} + +int reftable_reader_seek_log_at(struct reftable_reader *r, + struct reftable_iterator *it, const char *name, + uint64_t update_index) +{ + struct reftable_log_record log = { + .ref_name = (char *)name, + .update_index = update_index, + }; + struct reftable_record rec = { 0 }; + reftable_record_from_log(&rec, &log); + return reader_seek(r, it, &rec); +} + +int reftable_reader_seek_log(struct reftable_reader *r, + struct reftable_iterator *it, const char *name) +{ + uint64_t max = ~((uint64_t)0); + return reftable_reader_seek_log_at(r, it, name, max); +} + +void reader_close(struct reftable_reader *r) +{ + block_source_close(&r->source); + FREE_AND_NULL(r->name); +} + +int reftable_new_reader(struct reftable_reader **p, + struct reftable_block_source *src, char const *name) +{ + struct reftable_reader *rd = + reftable_calloc(sizeof(struct reftable_reader)); + int err = init_reader(rd, src, name); + if (err == 0) { + *p = rd; + } else { + block_source_close(src); + reftable_free(rd); + } + return err; +} + +void reftable_reader_free(struct reftable_reader *r) +{ + reader_close(r); + reftable_free(r); +} + +static int reftable_reader_refs_for_indexed(struct reftable_reader *r, + struct reftable_iterator *it, + uint8_t *oid) +{ + struct reftable_obj_record want = { + .hash_prefix = oid, + .hash_prefix_len = r->object_id_len, + }; + struct reftable_record want_rec = { 0 }; + struct reftable_iterator oit = { 0 }; + struct reftable_obj_record got = { 0 }; + struct reftable_record got_rec = { 0 }; + int err = 0; + struct indexed_table_ref_iter *itr = NULL; + + /* Look through the reverse index. */ + reftable_record_from_obj(&want_rec, &want); + err = reader_seek(r, &oit, &want_rec); + if (err != 0) + goto done; + + /* read out the reftable_obj_record */ + reftable_record_from_obj(&got_rec, &got); + err = iterator_next(&oit, &got_rec); + if (err < 0) + goto done; + + if (err > 0 || + memcmp(want.hash_prefix, got.hash_prefix, r->object_id_len)) { + /* didn't find it; return empty iterator */ + iterator_set_empty(it); + err = 0; + goto done; + } + + err = new_indexed_table_ref_iter(&itr, r, oid, hash_size(r->hash_id), + got.offsets, got.offset_len); + if (err < 0) + goto done; + got.offsets = NULL; + iterator_from_indexed_table_ref_iter(it, itr); + +done: + reftable_iterator_destroy(&oit); + reftable_record_clear(&got_rec); + return err; +} + +static int reftable_reader_refs_for_unindexed(struct reftable_reader *r, + struct reftable_iterator *it, + uint8_t *oid) +{ + struct table_iter ti_empty = TABLE_ITER_INIT; + struct table_iter *ti = reftable_calloc(sizeof(struct table_iter)); + struct filtering_ref_iterator *filter = NULL; + struct filtering_ref_iterator empty = FILTERING_REF_ITERATOR_INIT; + int oid_len = hash_size(r->hash_id); + int err; + + *ti = ti_empty; + err = reader_start(r, ti, BLOCK_TYPE_REF, false); + if (err < 0) { + reftable_free(ti); + return err; + } + + filter = reftable_malloc(sizeof(struct filtering_ref_iterator)); + *filter = empty; + + strbuf_add(&filter->oid, oid, oid_len); + reftable_table_from_reader(&filter->tab, r); + filter->double_check = false; + iterator_from_table_iter(&filter->it, ti); + + iterator_from_filtering_ref_iterator(it, filter); + return 0; +} + +int reftable_reader_refs_for(struct reftable_reader *r, + struct reftable_iterator *it, uint8_t *oid) +{ + if (r->obj_offsets.present) + return reftable_reader_refs_for_indexed(r, it, oid); + return reftable_reader_refs_for_unindexed(r, it, oid); +} + +uint64_t reftable_reader_max_update_index(struct reftable_reader *r) +{ + return r->max_update_index; +} + +uint64_t reftable_reader_min_update_index(struct reftable_reader *r) +{ + return r->min_update_index; +} diff --git a/reftable/reader.h b/reftable/reader.h new file mode 100644 index 00000000000..213e8fe847c --- /dev/null +++ b/reftable/reader.h @@ -0,0 +1,65 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef READER_H +#define READER_H + +#include "block.h" +#include "record.h" +#include "reftable.h" + +uint64_t block_source_size(struct reftable_block_source *source); + +int block_source_read_block(struct reftable_block_source *source, + struct reftable_block *dest, uint64_t off, + uint32_t size); +void block_source_close(struct reftable_block_source *source); + +/* metadata for a block type */ +struct reftable_reader_offsets { + bool present; + uint64_t offset; + uint64_t index_offset; +}; + +/* The state for reading a reftable file. */ +struct reftable_reader { + /* for convience, associate a name with the instance. */ + char *name; + struct reftable_block_source source; + + /* Size of the file, excluding the footer. */ + uint64_t size; + + /* 'sha1' for SHA1, 's256' for SHA-256 */ + uint32_t hash_id; + + uint32_t block_size; + uint64_t min_update_index; + uint64_t max_update_index; + /* Length of the OID keys in the 'o' section */ + int object_id_len; + int version; + + struct reftable_reader_offsets ref_offsets; + struct reftable_reader_offsets obj_offsets; + struct reftable_reader_offsets log_offsets; +}; + +int init_reader(struct reftable_reader *r, struct reftable_block_source *source, + const char *name); +int reader_seek(struct reftable_reader *r, struct reftable_iterator *it, + struct reftable_record *rec); +void reader_close(struct reftable_reader *r); +const char *reader_name(struct reftable_reader *r); + +/* initialize a block reader to read from `r` */ +int reader_init_block_reader(struct reftable_reader *r, struct block_reader *br, + uint64_t next_off, uint8_t want_typ); + +#endif diff --git a/reftable/record.c b/reftable/record.c new file mode 100644 index 00000000000..1e87d437035 --- /dev/null +++ b/reftable/record.c @@ -0,0 +1,1126 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +/* record.c - methods for different types of records. */ + +#include "record.h" + +#include "system.h" +#include "constants.h" +#include "reftable.h" +#include "basics.h" + +int get_var_int(uint64_t *dest, struct string_view *in) +{ + int ptr = 0; + uint64_t val; + + if (in->len == 0) + return -1; + val = in->buf[ptr] & 0x7f; + + while (in->buf[ptr] & 0x80) { + ptr++; + if (ptr > in->len) { + return -1; + } + val = (val + 1) << 7 | (uint64_t)(in->buf[ptr] & 0x7f); + } + + *dest = val; + return ptr + 1; +} + +int put_var_int(struct string_view *dest, uint64_t val) +{ + uint8_t buf[10] = { 0 }; + int i = 9; + int n = 0; + buf[i] = (uint8_t)(val & 0x7f); + i--; + while (true) { + val >>= 7; + if (!val) { + break; + } + val--; + buf[i] = 0x80 | (uint8_t)(val & 0x7f); + i--; + } + + n = sizeof(buf) - i - 1; + if (dest->len < n) + return -1; + memcpy(dest->buf, &buf[i + 1], n); + return n; +} + +int reftable_is_block_type(uint8_t typ) +{ + switch (typ) { + case BLOCK_TYPE_REF: + case BLOCK_TYPE_LOG: + case BLOCK_TYPE_OBJ: + case BLOCK_TYPE_INDEX: + return true; + } + return false; +} + +static int decode_string(struct strbuf *dest, struct string_view in) +{ + int start_len = in.len; + uint64_t tsize = 0; + int n = get_var_int(&tsize, &in); + if (n <= 0) + return -1; + string_view_consume(&in, n); + if (in.len < tsize) + return -1; + + strbuf_reset(dest); + strbuf_add(dest, in.buf, tsize); + string_view_consume(&in, tsize); + + return start_len - in.len; +} + +static int encode_string(char *str, struct string_view s) +{ + struct string_view start = s; + int l = strlen(str); + int n = put_var_int(&s, l); + if (n < 0) + return -1; + string_view_consume(&s, n); + if (s.len < l) + return -1; + memcpy(s.buf, str, l); + string_view_consume(&s, l); + + return start.len - s.len; +} + +int reftable_encode_key(bool *restart, struct string_view dest, + struct strbuf prev_key, struct strbuf key, + uint8_t extra) +{ + struct string_view start = dest; + int prefix_len = common_prefix_size(&prev_key, &key); + uint64_t suffix_len = key.len - prefix_len; + int n = put_var_int(&dest, (uint64_t)prefix_len); + if (n < 0) + return -1; + string_view_consume(&dest, n); + + *restart = (prefix_len == 0); + + n = put_var_int(&dest, suffix_len << 3 | (uint64_t)extra); + if (n < 0) + return -1; + string_view_consume(&dest, n); + + if (dest.len < suffix_len) + return -1; + memcpy(dest.buf, key.buf + prefix_len, suffix_len); + string_view_consume(&dest, suffix_len); + + return start.len - dest.len; +} + +int reftable_decode_key(struct strbuf *key, uint8_t *extra, + struct strbuf last_key, struct string_view in) +{ + int start_len = in.len; + uint64_t prefix_len = 0; + uint64_t suffix_len = 0; + int n = get_var_int(&prefix_len, &in); + if (n < 0) + return -1; + string_view_consume(&in, n); + + if (prefix_len > last_key.len) + return -1; + + n = get_var_int(&suffix_len, &in); + if (n <= 0) + return -1; + string_view_consume(&in, n); + + *extra = (uint8_t)(suffix_len & 0x7); + suffix_len >>= 3; + + if (in.len < suffix_len) + return -1; + + strbuf_reset(key); + strbuf_add(key, last_key.buf, prefix_len); + strbuf_add(key, in.buf, suffix_len); + string_view_consume(&in, suffix_len); + + return start_len - in.len; +} + +static void reftable_ref_record_key(const void *r, struct strbuf *dest) +{ + const struct reftable_ref_record *rec = + (const struct reftable_ref_record *)r; + strbuf_reset(dest); + strbuf_addstr(dest, rec->ref_name); +} + +static void reftable_ref_record_copy_from(void *rec, const void *src_rec, + int hash_size) +{ + struct reftable_ref_record *ref = (struct reftable_ref_record *)rec; + struct reftable_ref_record *src = (struct reftable_ref_record *)src_rec; + assert(hash_size > 0); + + /* This is simple and correct, but we could probably reuse the hash + fields. */ + reftable_ref_record_clear(ref); + if (src->ref_name != NULL) { + ref->ref_name = xstrdup(src->ref_name); + } + + if (src->target != NULL) { + ref->target = xstrdup(src->target); + } + + if (src->target_value != NULL) { + ref->target_value = reftable_malloc(hash_size); + memcpy(ref->target_value, src->target_value, hash_size); + } + + if (src->value != NULL) { + ref->value = reftable_malloc(hash_size); + memcpy(ref->value, src->value, hash_size); + } + ref->update_index = src->update_index; +} + +static char hexdigit(int c) +{ + if (c <= 9) + return '0' + c; + return 'a' + (c - 10); +} + +static void hex_format(char *dest, uint8_t *src, int hash_size) +{ + assert(hash_size > 0); + if (src != NULL) { + int i = 0; + for (i = 0; i < hash_size; i++) { + dest[2 * i] = hexdigit(src[i] >> 4); + dest[2 * i + 1] = hexdigit(src[i] & 0xf); + } + dest[2 * hash_size] = 0; + } +} + +void reftable_ref_record_print(struct reftable_ref_record *ref, + uint32_t hash_id) +{ + char hex[SHA256_SIZE + 1] = { 0 }; + printf("ref{%s(%" PRIu64 ") ", ref->ref_name, ref->update_index); + if (ref->value != NULL) { + hex_format(hex, ref->value, hash_size(hash_id)); + printf("%s", hex); + } + if (ref->target_value != NULL) { + hex_format(hex, ref->target_value, hash_size(hash_id)); + printf(" (T %s)", hex); + } + if (ref->target != NULL) { + printf("=> %s", ref->target); + } + printf("}\n"); +} + +static void reftable_ref_record_clear_void(void *rec) +{ + reftable_ref_record_clear((struct reftable_ref_record *)rec); +} + +void reftable_ref_record_clear(struct reftable_ref_record *ref) +{ + reftable_free(ref->ref_name); + reftable_free(ref->target); + reftable_free(ref->target_value); + reftable_free(ref->value); + memset(ref, 0, sizeof(struct reftable_ref_record)); +} + +static uint8_t reftable_ref_record_val_type(const void *rec) +{ + const struct reftable_ref_record *r = + (const struct reftable_ref_record *)rec; + if (r->value != NULL) { + if (r->target_value != NULL) { + return 2; + } else { + return 1; + } + } else if (r->target != NULL) + return 3; + return 0; +} + +static int reftable_ref_record_encode(const void *rec, struct string_view s, + int hash_size) +{ + const struct reftable_ref_record *r = + (const struct reftable_ref_record *)rec; + struct string_view start = s; + int n = put_var_int(&s, r->update_index); + assert(hash_size > 0); + if (n < 0) + return -1; + string_view_consume(&s, n); + + if (r->value != NULL) { + if (s.len < hash_size) { + return -1; + } + memcpy(s.buf, r->value, hash_size); + string_view_consume(&s, hash_size); + } + + if (r->target_value != NULL) { + if (s.len < hash_size) { + return -1; + } + memcpy(s.buf, r->target_value, hash_size); + string_view_consume(&s, hash_size); + } + + if (r->target != NULL) { + int n = encode_string(r->target, s); + if (n < 0) { + return -1; + } + string_view_consume(&s, n); + } + + return start.len - s.len; +} + +static int reftable_ref_record_decode(void *rec, struct strbuf key, + uint8_t val_type, struct string_view in, + int hash_size) +{ + struct reftable_ref_record *r = (struct reftable_ref_record *)rec; + struct string_view start = in; + bool seen_value = false; + bool seen_target_value = false; + bool seen_target = false; + + int n = get_var_int(&r->update_index, &in); + if (n < 0) + return n; + assert(hash_size > 0); + + string_view_consume(&in, n); + + r->ref_name = reftable_realloc(r->ref_name, key.len + 1); + memcpy(r->ref_name, key.buf, key.len); + r->ref_name[key.len] = 0; + + switch (val_type) { + case 1: + case 2: + if (in.len < hash_size) { + return -1; + } + + if (r->value == NULL) { + r->value = reftable_malloc(hash_size); + } + seen_value = true; + memcpy(r->value, in.buf, hash_size); + string_view_consume(&in, hash_size); + if (val_type == 1) { + break; + } + if (r->target_value == NULL) { + r->target_value = reftable_malloc(hash_size); + } + seen_target_value = true; + memcpy(r->target_value, in.buf, hash_size); + string_view_consume(&in, hash_size); + break; + case 3: { + struct strbuf dest = STRBUF_INIT; + int n = decode_string(&dest, in); + if (n < 0) { + return -1; + } + string_view_consume(&in, n); + seen_target = true; + if (r->target != NULL) { + reftable_free(r->target); + } + r->target = dest.buf; + } break; + + case 0: + break; + default: + abort(); + break; + } + + if (!seen_target && r->target != NULL) { + FREE_AND_NULL(r->target); + } + if (!seen_target_value && r->target_value != NULL) { + FREE_AND_NULL(r->target_value); + } + if (!seen_value && r->value != NULL) { + FREE_AND_NULL(r->value); + } + + return start.len - in.len; +} + +static bool reftable_ref_record_is_deletion_void(const void *p) +{ + return reftable_ref_record_is_deletion( + (const struct reftable_ref_record *)p); +} + +struct reftable_record_vtable reftable_ref_record_vtable = { + .key = &reftable_ref_record_key, + .type = BLOCK_TYPE_REF, + .copy_from = &reftable_ref_record_copy_from, + .val_type = &reftable_ref_record_val_type, + .encode = &reftable_ref_record_encode, + .decode = &reftable_ref_record_decode, + .clear = &reftable_ref_record_clear_void, + .is_deletion = &reftable_ref_record_is_deletion_void, +}; + +static void reftable_obj_record_key(const void *r, struct strbuf *dest) +{ + const struct reftable_obj_record *rec = + (const struct reftable_obj_record *)r; + strbuf_reset(dest); + strbuf_add(dest, rec->hash_prefix, rec->hash_prefix_len); +} + +static void reftable_obj_record_clear(void *rec) +{ + struct reftable_obj_record *obj = (struct reftable_obj_record *)rec; + FREE_AND_NULL(obj->hash_prefix); + FREE_AND_NULL(obj->offsets); + memset(obj, 0, sizeof(struct reftable_obj_record)); +} + +static void reftable_obj_record_copy_from(void *rec, const void *src_rec, + int hash_size) +{ + struct reftable_obj_record *obj = (struct reftable_obj_record *)rec; + const struct reftable_obj_record *src = + (const struct reftable_obj_record *)src_rec; + int olen; + + reftable_obj_record_clear(obj); + *obj = *src; + obj->hash_prefix = reftable_malloc(obj->hash_prefix_len); + memcpy(obj->hash_prefix, src->hash_prefix, obj->hash_prefix_len); + + olen = obj->offset_len * sizeof(uint64_t); + obj->offsets = reftable_malloc(olen); + memcpy(obj->offsets, src->offsets, olen); +} + +static uint8_t reftable_obj_record_val_type(const void *rec) +{ + struct reftable_obj_record *r = (struct reftable_obj_record *)rec; + if (r->offset_len > 0 && r->offset_len < 8) + return r->offset_len; + return 0; +} + +static int reftable_obj_record_encode(const void *rec, struct string_view s, + int hash_size) +{ + struct reftable_obj_record *r = (struct reftable_obj_record *)rec; + struct string_view start = s; + int i = 0; + int n = 0; + uint64_t last = 0; + if (r->offset_len == 0 || r->offset_len >= 8) { + n = put_var_int(&s, r->offset_len); + if (n < 0) { + return -1; + } + string_view_consume(&s, n); + } + if (r->offset_len == 0) + return start.len - s.len; + n = put_var_int(&s, r->offsets[0]); + if (n < 0) + return -1; + string_view_consume(&s, n); + + last = r->offsets[0]; + for (i = 1; i < r->offset_len; i++) { + int n = put_var_int(&s, r->offsets[i] - last); + if (n < 0) { + return -1; + } + string_view_consume(&s, n); + last = r->offsets[i]; + } + return start.len - s.len; +} + +static int reftable_obj_record_decode(void *rec, struct strbuf key, + uint8_t val_type, struct string_view in, + int hash_size) +{ + struct string_view start = in; + struct reftable_obj_record *r = (struct reftable_obj_record *)rec; + uint64_t count = val_type; + int n = 0; + uint64_t last; + int j; + r->hash_prefix = reftable_malloc(key.len); + memcpy(r->hash_prefix, key.buf, key.len); + r->hash_prefix_len = key.len; + + if (val_type == 0) { + n = get_var_int(&count, &in); + if (n < 0) { + return n; + } + + string_view_consume(&in, n); + } + + r->offsets = NULL; + r->offset_len = 0; + if (count == 0) + return start.len - in.len; + + r->offsets = reftable_malloc(count * sizeof(uint64_t)); + r->offset_len = count; + + n = get_var_int(&r->offsets[0], &in); + if (n < 0) + return n; + string_view_consume(&in, n); + + last = r->offsets[0]; + j = 1; + while (j < count) { + uint64_t delta = 0; + int n = get_var_int(&delta, &in); + if (n < 0) { + return n; + } + string_view_consume(&in, n); + + last = r->offsets[j] = (delta + last); + j++; + } + return start.len - in.len; +} + +static bool not_a_deletion(const void *p) +{ + return false; +} + +struct reftable_record_vtable reftable_obj_record_vtable = { + .key = &reftable_obj_record_key, + .type = BLOCK_TYPE_OBJ, + .copy_from = &reftable_obj_record_copy_from, + .val_type = &reftable_obj_record_val_type, + .encode = &reftable_obj_record_encode, + .decode = &reftable_obj_record_decode, + .clear = &reftable_obj_record_clear, + .is_deletion = not_a_deletion, +}; + +void reftable_log_record_print(struct reftable_log_record *log, + uint32_t hash_id) +{ + char hex[SHA256_SIZE + 1] = { 0 }; + + printf("log{%s(%" PRIu64 ") %s <%s> %" PRIu64 " %04d\n", log->ref_name, + log->update_index, log->name, log->email, log->time, + log->tz_offset); + hex_format(hex, log->old_hash, hash_size(hash_id)); + printf("%s => ", hex); + hex_format(hex, log->new_hash, hash_size(hash_id)); + printf("%s\n\n%s\n}\n", hex, log->message); +} + +static void reftable_log_record_key(const void *r, struct strbuf *dest) +{ + const struct reftable_log_record *rec = + (const struct reftable_log_record *)r; + int len = strlen(rec->ref_name); + uint8_t i64[8]; + uint64_t ts = 0; + strbuf_reset(dest); + strbuf_add(dest, (uint8_t *)rec->ref_name, len + 1); + + ts = (~ts) - rec->update_index; + put_be64(&i64[0], ts); + strbuf_add(dest, i64, sizeof(i64)); +} + +static void reftable_log_record_copy_from(void *rec, const void *src_rec, + int hash_size) +{ + struct reftable_log_record *dst = (struct reftable_log_record *)rec; + const struct reftable_log_record *src = + (const struct reftable_log_record *)src_rec; + + reftable_log_record_clear(dst); + *dst = *src; + if (dst->ref_name != NULL) { + dst->ref_name = xstrdup(dst->ref_name); + } + if (dst->email != NULL) { + dst->email = xstrdup(dst->email); + } + if (dst->name != NULL) { + dst->name = xstrdup(dst->name); + } + if (dst->message != NULL) { + dst->message = xstrdup(dst->message); + } + + if (dst->new_hash != NULL) { + dst->new_hash = reftable_malloc(hash_size); + memcpy(dst->new_hash, src->new_hash, hash_size); + } + if (dst->old_hash != NULL) { + dst->old_hash = reftable_malloc(hash_size); + memcpy(dst->old_hash, src->old_hash, hash_size); + } +} + +static void reftable_log_record_clear_void(void *rec) +{ + struct reftable_log_record *r = (struct reftable_log_record *)rec; + reftable_log_record_clear(r); +} + +void reftable_log_record_clear(struct reftable_log_record *r) +{ + reftable_free(r->ref_name); + reftable_free(r->new_hash); + reftable_free(r->old_hash); + reftable_free(r->name); + reftable_free(r->email); + reftable_free(r->message); + memset(r, 0, sizeof(struct reftable_log_record)); +} + +static uint8_t reftable_log_record_val_type(const void *rec) +{ + const struct reftable_log_record *log = + (const struct reftable_log_record *)rec; + + return reftable_log_record_is_deletion(log) ? 0 : 1; +} + +static uint8_t zero[SHA256_SIZE] = { 0 }; + +static int reftable_log_record_encode(const void *rec, struct string_view s, + int hash_size) +{ + struct reftable_log_record *r = (struct reftable_log_record *)rec; + struct string_view start = s; + int n = 0; + uint8_t *oldh = r->old_hash; + uint8_t *newh = r->new_hash; + if (reftable_log_record_is_deletion(r)) + return 0; + + if (oldh == NULL) { + oldh = zero; + } + if (newh == NULL) { + newh = zero; + } + + if (s.len < 2 * hash_size) + return -1; + + memcpy(s.buf, oldh, hash_size); + memcpy(s.buf + hash_size, newh, hash_size); + string_view_consume(&s, 2 * hash_size); + + n = encode_string(r->name ? r->name : "", s); + if (n < 0) + return -1; + string_view_consume(&s, n); + + n = encode_string(r->email ? r->email : "", s); + if (n < 0) + return -1; + string_view_consume(&s, n); + + n = put_var_int(&s, r->time); + if (n < 0) + return -1; + string_view_consume(&s, n); + + if (s.len < 2) + return -1; + + put_be16(s.buf, r->tz_offset); + string_view_consume(&s, 2); + + n = encode_string(r->message ? r->message : "", s); + if (n < 0) + return -1; + string_view_consume(&s, n); + + return start.len - s.len; +} + +static int reftable_log_record_decode(void *rec, struct strbuf key, + uint8_t val_type, struct string_view in, + int hash_size) +{ + struct string_view start = in; + struct reftable_log_record *r = (struct reftable_log_record *)rec; + uint64_t max = 0; + uint64_t ts = 0; + struct strbuf dest = STRBUF_INIT; + int n; + + if (key.len <= 9 || key.buf[key.len - 9] != 0) + return REFTABLE_FORMAT_ERROR; + + r->ref_name = reftable_realloc(r->ref_name, key.len - 8); + memcpy(r->ref_name, key.buf, key.len - 8); + ts = get_be64(key.buf + key.len - 8); + + r->update_index = (~max) - ts; + + if (val_type == 0) { + FREE_AND_NULL(r->old_hash); + FREE_AND_NULL(r->new_hash); + FREE_AND_NULL(r->message); + FREE_AND_NULL(r->email); + FREE_AND_NULL(r->name); + return 0; + } + + if (in.len < 2 * hash_size) + return REFTABLE_FORMAT_ERROR; + + r->old_hash = reftable_realloc(r->old_hash, hash_size); + r->new_hash = reftable_realloc(r->new_hash, hash_size); + + memcpy(r->old_hash, in.buf, hash_size); + memcpy(r->new_hash, in.buf + hash_size, hash_size); + + string_view_consume(&in, 2 * hash_size); + + n = decode_string(&dest, in); + if (n < 0) + goto done; + string_view_consume(&in, n); + + r->name = reftable_realloc(r->name, dest.len + 1); + memcpy(r->name, dest.buf, dest.len); + r->name[dest.len] = 0; + + strbuf_reset(&dest); + n = decode_string(&dest, in); + if (n < 0) + goto done; + string_view_consume(&in, n); + + r->email = reftable_realloc(r->email, dest.len + 1); + memcpy(r->email, dest.buf, dest.len); + r->email[dest.len] = 0; + + ts = 0; + n = get_var_int(&ts, &in); + if (n < 0) + goto done; + string_view_consume(&in, n); + r->time = ts; + if (in.len < 2) + goto done; + + r->tz_offset = get_be16(in.buf); + string_view_consume(&in, 2); + + strbuf_reset(&dest); + n = decode_string(&dest, in); + if (n < 0) + goto done; + string_view_consume(&in, n); + + r->message = reftable_realloc(r->message, dest.len + 1); + memcpy(r->message, dest.buf, dest.len); + r->message[dest.len] = 0; + + strbuf_release(&dest); + return start.len - in.len; + +done: + strbuf_release(&dest); + return REFTABLE_FORMAT_ERROR; +} + +static bool null_streq(char *a, char *b) +{ + char *empty = ""; + if (a == NULL) + a = empty; + + if (b == NULL) + b = empty; + + return 0 == strcmp(a, b); +} + +static bool zero_hash_eq(uint8_t *a, uint8_t *b, int sz) +{ + if (a == NULL) + a = zero; + + if (b == NULL) + b = zero; + + return !memcmp(a, b, sz); +} + +bool reftable_log_record_equal(struct reftable_log_record *a, + struct reftable_log_record *b, int hash_size) +{ + return null_streq(a->name, b->name) && null_streq(a->email, b->email) && + null_streq(a->message, b->message) && + zero_hash_eq(a->old_hash, b->old_hash, hash_size) && + zero_hash_eq(a->new_hash, b->new_hash, hash_size) && + a->time == b->time && a->tz_offset == b->tz_offset && + a->update_index == b->update_index; +} + +static bool reftable_log_record_is_deletion_void(const void *p) +{ + return reftable_log_record_is_deletion( + (const struct reftable_log_record *)p); +} + +struct reftable_record_vtable reftable_log_record_vtable = { + .key = &reftable_log_record_key, + .type = BLOCK_TYPE_LOG, + .copy_from = &reftable_log_record_copy_from, + .val_type = &reftable_log_record_val_type, + .encode = &reftable_log_record_encode, + .decode = &reftable_log_record_decode, + .clear = &reftable_log_record_clear_void, + .is_deletion = &reftable_log_record_is_deletion_void, +}; + +struct reftable_record reftable_new_record(uint8_t typ) +{ + struct reftable_record rec = { NULL }; + switch (typ) { + case BLOCK_TYPE_REF: { + struct reftable_ref_record *r = + reftable_calloc(sizeof(struct reftable_ref_record)); + reftable_record_from_ref(&rec, r); + return rec; + } + + case BLOCK_TYPE_OBJ: { + struct reftable_obj_record *r = + reftable_calloc(sizeof(struct reftable_obj_record)); + reftable_record_from_obj(&rec, r); + return rec; + } + case BLOCK_TYPE_LOG: { + struct reftable_log_record *r = + reftable_calloc(sizeof(struct reftable_log_record)); + reftable_record_from_log(&rec, r); + return rec; + } + case BLOCK_TYPE_INDEX: { + struct reftable_index_record empty = { .last_key = + STRBUF_INIT }; + struct reftable_index_record *r = + reftable_calloc(sizeof(struct reftable_index_record)); + *r = empty; + reftable_record_from_index(&rec, r); + return rec; + } + } + abort(); + return rec; +} + +void *reftable_record_yield(struct reftable_record *rec) +{ + void *p = rec->data; + rec->data = NULL; + return p; +} + +void reftable_record_destroy(struct reftable_record *rec) +{ + reftable_record_clear(rec); + reftable_free(reftable_record_yield(rec)); +} + +static void reftable_index_record_key(const void *r, struct strbuf *dest) +{ + struct reftable_index_record *rec = (struct reftable_index_record *)r; + strbuf_reset(dest); + strbuf_addbuf(dest, &rec->last_key); +} + +static void reftable_index_record_copy_from(void *rec, const void *src_rec, + int hash_size) +{ + struct reftable_index_record *dst = (struct reftable_index_record *)rec; + struct reftable_index_record *src = + (struct reftable_index_record *)src_rec; + + strbuf_reset(&dst->last_key); + strbuf_addbuf(&dst->last_key, &src->last_key); + dst->offset = src->offset; +} + +static void reftable_index_record_clear(void *rec) +{ + struct reftable_index_record *idx = (struct reftable_index_record *)rec; + strbuf_release(&idx->last_key); +} + +static uint8_t reftable_index_record_val_type(const void *rec) +{ + return 0; +} + +static int reftable_index_record_encode(const void *rec, struct string_view out, + int hash_size) +{ + const struct reftable_index_record *r = + (const struct reftable_index_record *)rec; + struct string_view start = out; + + int n = put_var_int(&out, r->offset); + if (n < 0) + return n; + + string_view_consume(&out, n); + + return start.len - out.len; +} + +static int reftable_index_record_decode(void *rec, struct strbuf key, + uint8_t val_type, struct string_view in, + int hash_size) +{ + struct string_view start = in; + struct reftable_index_record *r = (struct reftable_index_record *)rec; + int n = 0; + + strbuf_reset(&r->last_key); + strbuf_addbuf(&r->last_key, &key); + + n = get_var_int(&r->offset, &in); + if (n < 0) + return n; + + string_view_consume(&in, n); + return start.len - in.len; +} + +struct reftable_record_vtable reftable_index_record_vtable = { + .key = &reftable_index_record_key, + .type = BLOCK_TYPE_INDEX, + .copy_from = &reftable_index_record_copy_from, + .val_type = &reftable_index_record_val_type, + .encode = &reftable_index_record_encode, + .decode = &reftable_index_record_decode, + .clear = &reftable_index_record_clear, + .is_deletion = ¬_a_deletion, +}; + +void reftable_record_key(struct reftable_record *rec, struct strbuf *dest) +{ + rec->ops->key(rec->data, dest); +} + +uint8_t reftable_record_type(struct reftable_record *rec) +{ + return rec->ops->type; +} + +int reftable_record_encode(struct reftable_record *rec, struct string_view dest, + int hash_size) +{ + return rec->ops->encode(rec->data, dest, hash_size); +} + +void reftable_record_copy_from(struct reftable_record *rec, + struct reftable_record *src, int hash_size) +{ + assert(src->ops->type == rec->ops->type); + + rec->ops->copy_from(rec->data, src->data, hash_size); +} + +uint8_t reftable_record_val_type(struct reftable_record *rec) +{ + return rec->ops->val_type(rec->data); +} + +int reftable_record_decode(struct reftable_record *rec, struct strbuf key, + uint8_t extra, struct string_view src, int hash_size) +{ + return rec->ops->decode(rec->data, key, extra, src, hash_size); +} + +void reftable_record_clear(struct reftable_record *rec) +{ + rec->ops->clear(rec->data); +} + +bool reftable_record_is_deletion(struct reftable_record *rec) +{ + return rec->ops->is_deletion(rec->data); +} + +void reftable_record_from_ref(struct reftable_record *rec, + struct reftable_ref_record *ref_rec) +{ + assert(rec->ops == NULL); + rec->data = ref_rec; + rec->ops = &reftable_ref_record_vtable; +} + +void reftable_record_from_obj(struct reftable_record *rec, + struct reftable_obj_record *obj_rec) +{ + assert(rec->ops == NULL); + rec->data = obj_rec; + rec->ops = &reftable_obj_record_vtable; +} + +void reftable_record_from_index(struct reftable_record *rec, + struct reftable_index_record *index_rec) +{ + assert(rec->ops == NULL); + rec->data = index_rec; + rec->ops = &reftable_index_record_vtable; +} + +void reftable_record_from_log(struct reftable_record *rec, + struct reftable_log_record *log_rec) +{ + assert(rec->ops == NULL); + rec->data = log_rec; + rec->ops = &reftable_log_record_vtable; +} + +struct reftable_ref_record *reftable_record_as_ref(struct reftable_record *rec) +{ + assert(reftable_record_type(rec) == BLOCK_TYPE_REF); + return (struct reftable_ref_record *)rec->data; +} + +struct reftable_log_record *reftable_record_as_log(struct reftable_record *rec) +{ + assert(reftable_record_type(rec) == BLOCK_TYPE_LOG); + return (struct reftable_log_record *)rec->data; +} + +static bool hash_equal(uint8_t *a, uint8_t *b, int hash_size) +{ + if (a != NULL && b != NULL) + return !memcmp(a, b, hash_size); + + return a == b; +} + +static bool str_equal(char *a, char *b) +{ + if (a != NULL && b != NULL) + return 0 == strcmp(a, b); + + return a == b; +} + +bool reftable_ref_record_equal(struct reftable_ref_record *a, + struct reftable_ref_record *b, int hash_size) +{ + assert(hash_size > 0); + return 0 == strcmp(a->ref_name, b->ref_name) && + a->update_index == b->update_index && + hash_equal(a->value, b->value, hash_size) && + hash_equal(a->target_value, b->target_value, hash_size) && + str_equal(a->target, b->target); +} + +int reftable_ref_record_compare_name(const void *a, const void *b) +{ + return strcmp(((struct reftable_ref_record *)a)->ref_name, + ((struct reftable_ref_record *)b)->ref_name); +} + +bool reftable_ref_record_is_deletion(const struct reftable_ref_record *ref) +{ + return ref->value == NULL && ref->target == NULL && + ref->target_value == NULL; +} + +int reftable_log_record_compare_key(const void *a, const void *b) +{ + struct reftable_log_record *la = (struct reftable_log_record *)a; + struct reftable_log_record *lb = (struct reftable_log_record *)b; + + int cmp = strcmp(la->ref_name, lb->ref_name); + if (cmp) + return cmp; + if (la->update_index > lb->update_index) + return -1; + return (la->update_index < lb->update_index) ? 1 : 0; +} + +bool reftable_log_record_is_deletion(const struct reftable_log_record *log) +{ + return (log->new_hash == NULL && log->old_hash == NULL && + log->name == NULL && log->email == NULL && + log->message == NULL && log->time == 0 && log->tz_offset == 0 && + log->message == NULL); +} + +int hash_size(uint32_t id) +{ + switch (id) { + case 0: + case SHA1_ID: + return SHA1_SIZE; + case SHA256_ID: + return SHA256_SIZE; + } + abort(); +} + +void string_view_consume(struct string_view *s, int n) +{ + s->buf += n; + s->len -= n; +} diff --git a/reftable/record.h b/reftable/record.h new file mode 100644 index 00000000000..ba753dcec05 --- /dev/null +++ b/reftable/record.h @@ -0,0 +1,143 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef RECORD_H +#define RECORD_H + +#include "reftable.h" +#include "strbuf.h" +#include "system.h" + +/* + A substring of existing string data. This structure takes no responsibility + for the lifetime of the data it points to. +*/ +struct string_view { + uint8_t *buf; + int len; +}; + +/* Advance `s.buf` by `n`, and decrease length. */ +void string_view_consume(struct string_view *s, int n); + +/* utilities for de/encoding varints */ + +int get_var_int(uint64_t *dest, struct string_view *in); +int put_var_int(struct string_view *dest, uint64_t val); + +/* Methods for records. */ +struct reftable_record_vtable { + /* encode the key of to a uint8_t strbuf. */ + void (*key)(const void *rec, struct strbuf *dest); + + /* The record type of ('r' for ref). */ + uint8_t type; + + void (*copy_from)(void *dest, const void *src, int hash_size); + + /* a value of [0..7], indicating record subvariants (eg. ref vs. symref + * vs ref deletion) */ + uint8_t (*val_type)(const void *rec); + + /* encodes rec into dest, returning how much space was used. */ + int (*encode)(const void *rec, struct string_view dest, int hash_size); + + /* decode data from `src` into the record. */ + int (*decode)(void *rec, struct strbuf key, uint8_t extra, + struct string_view src, int hash_size); + + /* deallocate and null the record. */ + void (*clear)(void *rec); + + /* is this a tombstone? */ + bool (*is_deletion)(const void *rec); +}; + +/* record is a generic wrapper for different types of records. */ +struct reftable_record { + void *data; + struct reftable_record_vtable *ops; +}; + +/* returns true for recognized block types. Block start with the block type. */ +int reftable_is_block_type(uint8_t typ); + +/* creates a malloced record of the given type. Dispose with record_destroy */ +struct reftable_record reftable_new_record(uint8_t typ); + +extern struct reftable_record_vtable reftable_ref_record_vtable; + +/* Encode `key` into `dest`. Sets `restart` to indicate a restart. Returns + number of bytes written. */ +int reftable_encode_key(bool *restart, struct string_view dest, + struct strbuf prev_key, struct strbuf key, + uint8_t extra); + +/* Decode into `key` and `extra` from `in` */ +int reftable_decode_key(struct strbuf *key, uint8_t *extra, + struct strbuf last_key, struct string_view in); + +/* reftable_index_record are used internally to speed up lookups. */ +struct reftable_index_record { + uint64_t offset; /* Offset of block */ + struct strbuf last_key; /* Last key of the block. */ +}; + +/* reftable_obj_record stores an object ID => ref mapping. */ +struct reftable_obj_record { + uint8_t *hash_prefix; /* leading bytes of the object ID */ + int hash_prefix_len; /* number of leading bytes. Constant + * across a single table. */ + uint64_t *offsets; /* a vector of file offsets. */ + int offset_len; +}; + +/* see struct record_vtable */ + +void reftable_record_key(struct reftable_record *rec, struct strbuf *dest); +uint8_t reftable_record_type(struct reftable_record *rec); +void reftable_record_copy_from(struct reftable_record *rec, + struct reftable_record *src, int hash_size); +uint8_t reftable_record_val_type(struct reftable_record *rec); +int reftable_record_encode(struct reftable_record *rec, struct string_view dest, + int hash_size); +int reftable_record_decode(struct reftable_record *rec, struct strbuf key, + uint8_t extra, struct string_view src, + int hash_size); +bool reftable_record_is_deletion(struct reftable_record *rec); + +/* zeroes out the embedded record */ +void reftable_record_clear(struct reftable_record *rec); + +/* clear out the record, yielding the reftable_record data that was + * encapsulated. */ +void *reftable_record_yield(struct reftable_record *rec); + +/* clear and deallocate embedded record, and zero `rec`. */ +void reftable_record_destroy(struct reftable_record *rec); + +/* initialize generic records from concrete records. The generic record should + * be zeroed out. */ +void reftable_record_from_obj(struct reftable_record *rec, + struct reftable_obj_record *objrec); +void reftable_record_from_index(struct reftable_record *rec, + struct reftable_index_record *idxrec); +void reftable_record_from_ref(struct reftable_record *rec, + struct reftable_ref_record *refrec); +void reftable_record_from_log(struct reftable_record *rec, + struct reftable_log_record *logrec); +struct reftable_ref_record *reftable_record_as_ref(struct reftable_record *ref); +struct reftable_log_record *reftable_record_as_log(struct reftable_record *ref); + +/* for qsort. */ +int reftable_ref_record_compare_name(const void *a, const void *b); + +/* for qsort. */ +int reftable_log_record_compare_key(const void *a, const void *b); + +#endif diff --git a/reftable/record_test.c b/reftable/record_test.c new file mode 100644 index 00000000000..232e939e66d --- /dev/null +++ b/reftable/record_test.c @@ -0,0 +1,410 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "record.h" + +#include "system.h" +#include "basics.h" +#include "constants.h" +#include "reftable.h" +#include "test_framework.h" +#include "reftable-tests.h" + +static void test_copy(struct reftable_record *rec) +{ + struct reftable_record copy = + reftable_new_record(reftable_record_type(rec)); + reftable_record_copy_from(©, rec, SHA1_SIZE); + /* do it twice to catch memory leaks */ + reftable_record_copy_from(©, rec, SHA1_SIZE); + switch (reftable_record_type(©)) { + case BLOCK_TYPE_REF: + assert(reftable_ref_record_equal(reftable_record_as_ref(©), + reftable_record_as_ref(rec), + SHA1_SIZE)); + break; + case BLOCK_TYPE_LOG: + assert(reftable_log_record_equal(reftable_record_as_log(©), + reftable_record_as_log(rec), + SHA1_SIZE)); + break; + } + reftable_record_destroy(©); +} + +static void test_varint_roundtrip(void) +{ + uint64_t inputs[] = { 0, + 1, + 27, + 127, + 128, + 257, + 4096, + ((uint64_t)1 << 63), + ((uint64_t)1 << 63) + ((uint64_t)1 << 63) - 1 }; + int i = 0; + for (i = 0; i < ARRAY_SIZE(inputs); i++) { + uint8_t dest[10]; + + struct string_view out = { + .buf = dest, + .len = sizeof(dest), + }; + uint64_t in = inputs[i]; + int n = put_var_int(&out, in); + uint64_t got = 0; + + assert(n > 0); + out.len = n; + n = get_var_int(&got, &out); + assert(n > 0); + + assert(got == in); + } +} + +static void test_common_prefix(void) +{ + struct { + const char *a, *b; + int want; + } cases[] = { + { "abc", "ab", 2 }, + { "", "abc", 0 }, + { "abc", "abd", 2 }, + { "abc", "pqr", 0 }, + }; + + int i = 0; + for (i = 0; i < ARRAY_SIZE(cases); i++) { + struct strbuf a = STRBUF_INIT; + struct strbuf b = STRBUF_INIT; + strbuf_addstr(&a, cases[i].a); + strbuf_addstr(&b, cases[i].b); + assert(common_prefix_size(&a, &b) == cases[i].want); + + strbuf_release(&a); + strbuf_release(&b); + } +} + +static void set_hash(uint8_t *h, int j) +{ + int i = 0; + for (i = 0; i < hash_size(SHA1_ID); i++) { + h[i] = (j >> i) & 0xff; + } +} + +static void test_reftable_ref_record_roundtrip(void) +{ + int i = 0; + + for (i = 0; i <= 3; i++) { + struct reftable_ref_record in = { 0 }; + struct reftable_ref_record out = { + .ref_name = xstrdup("old name"), + .value = reftable_calloc(SHA1_SIZE), + .target_value = reftable_calloc(SHA1_SIZE), + .target = xstrdup("old value"), + }; + struct reftable_record rec_out = { 0 }; + struct strbuf key = STRBUF_INIT; + struct reftable_record rec = { 0 }; + uint8_t buffer[1024] = { 0 }; + struct string_view dest = { + .buf = buffer, + .len = sizeof(buffer), + }; + + int n, m; + + switch (i) { + case 0: + break; + case 1: + in.value = reftable_malloc(SHA1_SIZE); + set_hash(in.value, 1); + break; + case 2: + in.value = reftable_malloc(SHA1_SIZE); + set_hash(in.value, 1); + in.target_value = reftable_malloc(SHA1_SIZE); + set_hash(in.target_value, 2); + break; + case 3: + in.target = xstrdup("target"); + break; + } + in.ref_name = xstrdup("refs/heads/master"); + + reftable_record_from_ref(&rec, &in); + test_copy(&rec); + + assert(reftable_record_val_type(&rec) == i); + + reftable_record_key(&rec, &key); + n = reftable_record_encode(&rec, dest, SHA1_SIZE); + assert(n > 0); + + /* decode into a non-zero reftable_record to test for leaks. */ + + reftable_record_from_ref(&rec_out, &out); + m = reftable_record_decode(&rec_out, key, i, dest, SHA1_SIZE); + assert(n == m); + + assert((out.value != NULL) == (in.value != NULL)); + assert((out.target_value != NULL) == (in.target_value != NULL)); + assert((out.target != NULL) == (in.target != NULL)); + reftable_record_clear(&rec_out); + + strbuf_release(&key); + reftable_ref_record_clear(&in); + } +} + +static void test_reftable_log_record_equal(void) +{ + struct reftable_log_record in[2] = { + { + .ref_name = xstrdup("refs/heads/master"), + .update_index = 42, + }, + { + .ref_name = xstrdup("refs/heads/master"), + .update_index = 22, + } + }; + + assert(!reftable_log_record_equal(&in[0], &in[1], SHA1_SIZE)); + in[1].update_index = in[0].update_index; + assert(reftable_log_record_equal(&in[0], &in[1], SHA1_SIZE)); + reftable_log_record_clear(&in[0]); + reftable_log_record_clear(&in[1]); +} + +static void test_reftable_log_record_roundtrip(void) +{ + struct reftable_log_record in[2] = { + { + .ref_name = xstrdup("refs/heads/master"), + .old_hash = reftable_malloc(SHA1_SIZE), + .new_hash = reftable_malloc(SHA1_SIZE), + .name = xstrdup("han-wen"), + .email = xstrdup("hanwen@xxxxxxxxxx"), + .message = xstrdup("test"), + .update_index = 42, + .time = 1577123507, + .tz_offset = 100, + }, + { + .ref_name = xstrdup("refs/heads/master"), + .update_index = 22, + } + }; + set_test_hash(in[0].new_hash, 1); + set_test_hash(in[0].old_hash, 2); + for (int i = 0; i < ARRAY_SIZE(in); i++) { + struct reftable_record rec = { 0 }; + struct strbuf key = STRBUF_INIT; + uint8_t buffer[1024] = { 0 }; + struct string_view dest = { + .buf = buffer, + .len = sizeof(buffer), + }; + /* populate out, to check for leaks. */ + struct reftable_log_record out = { + .ref_name = xstrdup("old name"), + .new_hash = reftable_calloc(SHA1_SIZE), + .old_hash = reftable_calloc(SHA1_SIZE), + .name = xstrdup("old name"), + .email = xstrdup("old@email"), + .message = xstrdup("old message"), + }; + struct reftable_record rec_out = { 0 }; + int n, m, valtype; + + reftable_record_from_log(&rec, &in[i]); + + test_copy(&rec); + + reftable_record_key(&rec, &key); + + n = reftable_record_encode(&rec, dest, SHA1_SIZE); + assert(n >= 0); + reftable_record_from_log(&rec_out, &out); + valtype = reftable_record_val_type(&rec); + m = reftable_record_decode(&rec_out, key, valtype, dest, + SHA1_SIZE); + assert(n == m); + + assert(reftable_log_record_equal(&in[i], &out, SHA1_SIZE)); + reftable_log_record_clear(&in[i]); + strbuf_release(&key); + reftable_record_clear(&rec_out); + } +} + +static void test_u24_roundtrip(void) +{ + uint32_t in = 0x112233; + uint8_t dest[3]; + uint32_t out; + put_be24(dest, in); + out = get_be24(dest); + assert(in == out); +} + +static void test_key_roundtrip(void) +{ + uint8_t buffer[1024] = { 0 }; + struct string_view dest = { + .buf = buffer, + .len = sizeof(buffer), + }; + struct strbuf last_key = STRBUF_INIT; + struct strbuf key = STRBUF_INIT; + struct strbuf roundtrip = STRBUF_INIT; + bool restart; + uint8_t extra; + int n, m; + uint8_t rt_extra; + + strbuf_addstr(&last_key, "refs/heads/master"); + strbuf_addstr(&key, "refs/tags/bla"); + extra = 6; + n = reftable_encode_key(&restart, dest, last_key, key, extra); + assert(!restart); + assert(n > 0); + + m = reftable_decode_key(&roundtrip, &rt_extra, last_key, dest); + assert(n == m); + assert(0 == strbuf_cmp(&key, &roundtrip)); + assert(rt_extra == extra); + + strbuf_release(&last_key); + strbuf_release(&key); + strbuf_release(&roundtrip); +} + +static void test_reftable_obj_record_roundtrip(void) +{ + uint8_t testHash1[SHA1_SIZE] = { 1, 2, 3, 4, 0 }; + uint64_t till9[] = { 1, 2, 3, 4, 500, 600, 700, 800, 9000 }; + struct reftable_obj_record recs[3] = { { + .hash_prefix = testHash1, + .hash_prefix_len = 5, + .offsets = till9, + .offset_len = 3, + }, + { + .hash_prefix = testHash1, + .hash_prefix_len = 5, + .offsets = till9, + .offset_len = 9, + }, + { + .hash_prefix = testHash1, + .hash_prefix_len = 5, + } }; + int i = 0; + for (i = 0; i < ARRAY_SIZE(recs); i++) { + struct reftable_obj_record in = recs[i]; + uint8_t buffer[1024] = { 0 }; + struct string_view dest = { + .buf = buffer, + .len = sizeof(buffer), + }; + struct reftable_record rec = { 0 }; + struct strbuf key = STRBUF_INIT; + struct reftable_obj_record out = { 0 }; + struct reftable_record rec_out = { 0 }; + int n, m; + uint8_t extra; + + reftable_record_from_obj(&rec, &in); + test_copy(&rec); + reftable_record_key(&rec, &key); + n = reftable_record_encode(&rec, dest, SHA1_SIZE); + assert(n > 0); + extra = reftable_record_val_type(&rec); + reftable_record_from_obj(&rec_out, &out); + m = reftable_record_decode(&rec_out, key, extra, dest, + SHA1_SIZE); + assert(n == m); + + assert(in.hash_prefix_len == out.hash_prefix_len); + assert(in.offset_len == out.offset_len); + + assert(!memcmp(in.hash_prefix, out.hash_prefix, + in.hash_prefix_len)); + assert(0 == memcmp(in.offsets, out.offsets, + sizeof(uint64_t) * in.offset_len)); + strbuf_release(&key); + reftable_record_clear(&rec_out); + } +} + +static void test_reftable_index_record_roundtrip(void) +{ + struct reftable_index_record in = { + .offset = 42, + .last_key = STRBUF_INIT, + }; + uint8_t buffer[1024] = { 0 }; + struct string_view dest = { + .buf = buffer, + .len = sizeof(buffer), + }; + struct strbuf key = STRBUF_INIT; + struct reftable_record rec = { 0 }; + struct reftable_index_record out = { .last_key = STRBUF_INIT }; + struct reftable_record out_rec = { NULL }; + int n, m; + uint8_t extra; + + strbuf_addstr(&in.last_key, "refs/heads/master"); + reftable_record_from_index(&rec, &in); + reftable_record_key(&rec, &key); + test_copy(&rec); + + assert(0 == strbuf_cmp(&key, &in.last_key)); + n = reftable_record_encode(&rec, dest, SHA1_SIZE); + assert(n > 0); + + extra = reftable_record_val_type(&rec); + reftable_record_from_index(&out_rec, &out); + m = reftable_record_decode(&out_rec, key, extra, dest, SHA1_SIZE); + assert(m == n); + + assert(in.offset == out.offset); + + reftable_record_clear(&out_rec); + strbuf_release(&key); + strbuf_release(&in.last_key); +} + +int record_test_main(int argc, const char *argv[]) +{ + add_test_case("test_reftable_log_record_equal", + &test_reftable_log_record_equal); + add_test_case("test_reftable_log_record_roundtrip", + &test_reftable_log_record_roundtrip); + add_test_case("test_reftable_ref_record_roundtrip", + &test_reftable_ref_record_roundtrip); + add_test_case("test_varint_roundtrip", &test_varint_roundtrip); + add_test_case("test_key_roundtrip", &test_key_roundtrip); + add_test_case("test_common_prefix", &test_common_prefix); + add_test_case("test_reftable_obj_record_roundtrip", + &test_reftable_obj_record_roundtrip); + add_test_case("test_reftable_index_record_roundtrip", + &test_reftable_index_record_roundtrip); + add_test_case("test_u24_roundtrip", &test_u24_roundtrip); + return test_main(argc, argv); +} diff --git a/reftable/refname.c b/reftable/refname.c new file mode 100644 index 00000000000..6b2658fc158 --- /dev/null +++ b/reftable/refname.c @@ -0,0 +1,209 @@ +/* + Copyright 2020 Google LLC + + Use of this source code is governed by a BSD-style + license that can be found in the LICENSE file or at + https://developers.google.com/open-source/licenses/bsd +*/ + +#include "system.h" +#include "reftable.h" +#include "basics.h" +#include "refname.h" +#include "strbuf.h" + +struct find_arg { + char **names; + const char *want; +}; + +static int find_name(size_t k, void *arg) +{ + struct find_arg *f_arg = (struct find_arg *)arg; + return strcmp(f_arg->names[k], f_arg->want) >= 0; +} + +int modification_has_ref(struct modification *mod, const char *name) +{ + struct reftable_ref_record ref = { 0 }; + int err = 0; + + if (mod->add_len > 0) { + struct find_arg arg = { + .names = mod->add, + .want = name, + }; + int idx = binsearch(mod->add_len, find_name, &arg); + if (idx < mod->add_len && !strcmp(mod->add[idx], name)) { + return 0; + } + } + + if (mod->del_len > 0) { + struct find_arg arg = { + .names = mod->del, + .want = name, + }; + int idx = binsearch(mod->del_len, find_name, &arg); + if (idx < mod->del_len && !strcmp(mod->del[idx], name)) { + return 1; + } + } + + err = reftable_table_read_ref(&mod->tab, name, &ref); + reftable_ref_record_clear(&ref); + return err; +} + +static void modification_clear(struct modification *mod) +{ + /* don't delete the strings themselves; they're owned by ref records. + */ + FREE_AND_NULL(mod->add); + FREE_AND_NULL(mod->del); + mod->add_len = 0; + mod->del_len = 0; +} + +int modification_has_ref_with_prefix(struct modification *mod, + const char *prefix) +{ + struct reftable_iterator it = { NULL }; + struct reftable_ref_record ref = { NULL }; + int err = 0; + + if (mod->add_len > 0) { + struct find_arg arg = { + .names = mod->add, + .want = prefix, + }; + int idx = binsearch(mod->add_len, find_name, &arg); + if (idx < mod->add_len && + !strncmp(prefix, mod->add[idx], strlen(prefix))) + goto done; + } + err = reftable_table_seek_ref(&mod->tab, &it, prefix); + if (err) + goto done; + + while (true) { + err = reftable_iterator_next_ref(&it, &ref); + if (err) + goto done; + + if (mod->del_len > 0) { + struct find_arg arg = { + .names = mod->del, + .want = ref.ref_name, + }; + int idx = binsearch(mod->del_len, find_name, &arg); + if (idx < mod->del_len && + !strcmp(ref.ref_name, mod->del[idx])) { + continue; + } + } + + if (strncmp(ref.ref_name, prefix, strlen(prefix))) { + err = 1; + goto done; + } + err = 0; + goto done; + } + +done: + reftable_ref_record_clear(&ref); + reftable_iterator_destroy(&it); + return err; +} + +int validate_ref_name(const char *name) +{ + while (true) { + char *next = strchr(name, '/'); + if (!*name) { + return REFTABLE_REFNAME_ERROR; + } + if (!next) { + return 0; + } + if (next - name == 0 || (next - name == 1 && *name == '.') || + (next - name == 2 && name[0] == '.' && name[1] == '.')) + return REFTABLE_REFNAME_ERROR; + name = next + 1; + } + return 0; +} + +int validate_ref_record_addition(struct reftable_table tab, + struct reftable_ref_record *recs, size_t sz) +{ + struct modification mod = { + .tab = tab, + .add = reftable_calloc(sizeof(char *) * sz), + .del = reftable_calloc(sizeof(char *) * sz), + }; + int i = 0; + int err = 0; + for (; i < sz; i++) { + if (reftable_ref_record_is_deletion(&recs[i])) { + mod.del[mod.del_len++] = recs[i].ref_name; + } else { + mod.add[mod.add_len++] = recs[i].ref_name; + } + } + + err = modification_validate(&mod); + modification_clear(&mod); + return err; +} + +static void strbuf_trim_component(struct strbuf *sl) +{ + while (sl->len > 0) { + bool is_slash = (sl->buf[sl->len - 1] == '/'); + strbuf_setlen(sl, sl->len - 1); + if (is_slash) + break; + } +} + +int modification_validate(struct modification *mod) +{ + struct strbuf slashed = STRBUF_INIT; + int err = 0; + int i = 0; + for (; i < mod->add_len; i++) { + err = validate_ref_name(mod->add[i]); + if (err) + goto done; + strbuf_reset(&slashed); + strbuf_addstr(&slashed, mod->add[i]); + strbuf_addstr(&slashed, "/"); + + err = modification_has_ref_with_prefix(mod, slashed.buf); + if (err == 0) { + err = REFTABLE_NAME_CONFLICT; + goto done; + } + if (err < 0) + goto done; + + strbuf_reset(&slashed); + strbuf_addstr(&slashed, mod->add[i]); + while (slashed.len) { + strbuf_trim_component(&slashed); + err = modification_has_ref(mod, slashed.buf); + if (err == 0) { + err = REFTABLE_NAME_CONFLICT; + goto done; + } + if (err < 0) + goto done; + } + } + err = 0; +done: + strbuf_release(&slashed); + return err; +} diff --git a/reftable/refname.h b/reftable/refname.h new file mode 100644 index 00000000000..f335287fcdb --- /dev/null +++ b/reftable/refname.h @@ -0,0 +1,38 @@ +/* + Copyright 2020 Google LLC + + Use of this source code is governed by a BSD-style + license that can be found in the LICENSE file or at + https://developers.google.com/open-source/licenses/bsd +*/ +#ifndef REFNAME_H +#define REFNAME_H + +#include "reftable.h" + +struct modification { + struct reftable_table tab; + + char **add; + size_t add_len; + + char **del; + size_t del_len; +}; + +// -1 = error, 0 = found, 1 = not found +int modification_has_ref(struct modification *mod, const char *name); + +// -1 = error, 0 = found, 1 = not found. +int modification_has_ref_with_prefix(struct modification *mod, + const char *prefix); + +// 0 = OK. +int validate_ref_name(const char *name); + +int validate_ref_record_addition(struct reftable_table tab, + struct reftable_ref_record *recs, size_t sz); + +int modification_validate(struct modification *mod); + +#endif diff --git a/reftable/refname_test.c b/reftable/refname_test.c new file mode 100644 index 00000000000..4b1b6912539 --- /dev/null +++ b/reftable/refname_test.c @@ -0,0 +1,99 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "reftable.h" + +#include "basics.h" +#include "block.h" +#include "constants.h" +#include "reader.h" +#include "record.h" +#include "refname.h" +#include "system.h" + +#include "test_framework.h" +#include "reftable-tests.h" + +struct testcase { + char *add; + char *del; + int error_code; +}; + +static void test_conflict(void) +{ + struct reftable_write_options opts = { 0 }; + struct strbuf buf = STRBUF_INIT; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + struct reftable_ref_record rec = { + .ref_name = "a/b", + .target = "destination", /* make sure it's not a symref. */ + .update_index = 1, + }; + int err; + int i; + struct reftable_block_source source = { 0 }; + struct reftable_reader *rd = NULL; + struct reftable_table tab = { NULL }; + struct testcase cases[] = { + { "a/b/c", NULL, REFTABLE_NAME_CONFLICT }, + { "b", NULL, 0 }, + { "a", NULL, REFTABLE_NAME_CONFLICT }, + { "a", "a/b", 0 }, + + { "p/", NULL, REFTABLE_REFNAME_ERROR }, + { "p//q", NULL, REFTABLE_REFNAME_ERROR }, + { "p/./q", NULL, REFTABLE_REFNAME_ERROR }, + { "p/../q", NULL, REFTABLE_REFNAME_ERROR }, + + { "a/b/c", "a/b", 0 }, + { NULL, "a//b", 0 }, + }; + reftable_writer_set_limits(w, 1, 1); + + err = reftable_writer_add_ref(w, &rec); + assert_err(err); + + err = reftable_writer_close(w); + assert_err(err); + reftable_writer_free(w); + + block_source_from_strbuf(&source, &buf); + err = reftable_new_reader(&rd, &source, "filename"); + assert_err(err); + + reftable_table_from_reader(&tab, rd); + + for (i = 0; i < ARRAY_SIZE(cases); i++) { + struct modification mod = { + .tab = tab, + }; + + if (cases[i].add != NULL) { + mod.add = &cases[i].add; + mod.add_len = 1; + } + if (cases[i].del != NULL) { + mod.del = &cases[i].del; + mod.del_len = 1; + } + + err = modification_validate(&mod); + assert(err == cases[i].error_code); + } + + reftable_reader_free(rd); + strbuf_release(&buf); +} + +int refname_test_main(int argc, const char *argv[]) +{ + add_test_case("test_conflict", &test_conflict); + return test_main(argc, argv); +} diff --git a/reftable/reftable-tests.h b/reftable/reftable-tests.h new file mode 100644 index 00000000000..e38471888f7 --- /dev/null +++ b/reftable/reftable-tests.h @@ -0,0 +1,22 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef REFTABLE_TESTS_H +#define REFTABLE_TESTS_H + +int block_test_main(int argc, const char **argv); +int merged_test_main(int argc, const char **argv); +int record_test_main(int argc, const char **argv); +int refname_test_main(int argc, const char **argv); +int reftable_test_main(int argc, const char **argv); +int strbuf_test_main(int argc, const char **argv); +int stack_test_main(int argc, const char **argv); +int tree_test_main(int argc, const char **argv); +int reftable_dump_main(int argc, char *const *argv); + +#endif diff --git a/reftable/reftable.c b/reftable/reftable.c new file mode 100644 index 00000000000..6e7d1da10e7 --- /dev/null +++ b/reftable/reftable.c @@ -0,0 +1,90 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "reftable.h" +#include "record.h" +#include "reader.h" +#include "merged.h" + +struct reftable_table_vtable { + int (*seek)(void *tab, struct reftable_iterator *it, + struct reftable_record *); +}; + +static int reftable_reader_seek_void(void *tab, struct reftable_iterator *it, + struct reftable_record *rec) +{ + return reader_seek((struct reftable_reader *)tab, it, rec); +} + +static struct reftable_table_vtable reader_vtable = { + .seek = reftable_reader_seek_void, +}; + +static int reftable_merged_table_seek_void(void *tab, + struct reftable_iterator *it, + struct reftable_record *rec) +{ + return merged_table_seek_record((struct reftable_merged_table *)tab, it, + rec); +} + +static struct reftable_table_vtable merged_table_vtable = { + .seek = reftable_merged_table_seek_void, +}; + +int reftable_table_seek_ref(struct reftable_table *tab, + struct reftable_iterator *it, const char *name) +{ + struct reftable_ref_record ref = { + .ref_name = (char *)name, + }; + struct reftable_record rec = { 0 }; + reftable_record_from_ref(&rec, &ref); + return tab->ops->seek(tab->table_arg, it, &rec); +} + +void reftable_table_from_reader(struct reftable_table *tab, + struct reftable_reader *reader) +{ + assert(tab->ops == NULL); + tab->ops = &reader_vtable; + tab->table_arg = reader; +} + +void reftable_table_from_merged_table(struct reftable_table *tab, + struct reftable_merged_table *merged) +{ + assert(tab->ops == NULL); + tab->ops = &merged_table_vtable; + tab->table_arg = merged; +} + +int reftable_table_read_ref(struct reftable_table *tab, const char *name, + struct reftable_ref_record *ref) +{ + struct reftable_iterator it = { 0 }; + int err = reftable_table_seek_ref(tab, &it, name); + if (err) + goto done; + + err = reftable_iterator_next_ref(&it, ref); + if (err) + goto done; + + if (strcmp(ref->ref_name, name) || + reftable_ref_record_is_deletion(ref)) { + reftable_ref_record_clear(ref); + err = 1; + goto done; + } + +done: + reftable_iterator_destroy(&it); + return err; +} diff --git a/reftable/reftable.h b/reftable/reftable.h new file mode 100644 index 00000000000..52e869c4a47 --- /dev/null +++ b/reftable/reftable.h @@ -0,0 +1,571 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef REFTABLE_H +#define REFTABLE_H + +#include <stdint.h> +#include <stddef.h> + +void reftable_set_alloc(void *(*malloc)(size_t), + void *(*realloc)(void *, size_t), void (*free)(void *)); + +/**************************************************************** + Basic data types + + Reftables store the state of each ref in struct reftable_ref_record, and they + store a sequence of reflog updates in struct reftable_log_record. + ****************************************************************/ + +/* reftable_ref_record holds a ref database entry target_value */ +struct reftable_ref_record { + char *ref_name; /* Name of the ref, malloced. */ + uint64_t update_index; /* Logical timestamp at which this value is + written */ + uint8_t *value; /* SHA1, or NULL. malloced. */ + uint8_t *target_value; /* peeled annotated tag, or NULL. malloced. */ + char *target; /* symref, or NULL. malloced. */ +}; + +/* returns whether 'ref' represents a deletion */ +int reftable_ref_record_is_deletion(const struct reftable_ref_record *ref); + +/* prints a reftable_ref_record onto stdout */ +void reftable_ref_record_print(struct reftable_ref_record *ref, + uint32_t hash_id); + +/* frees and nulls all pointer values. */ +void reftable_ref_record_clear(struct reftable_ref_record *ref); + +/* returns whether two reftable_ref_records are the same */ +int reftable_ref_record_equal(struct reftable_ref_record *a, + struct reftable_ref_record *b, int hash_size); + +/* reftable_log_record holds a reflog entry */ +struct reftable_log_record { + char *ref_name; + uint64_t update_index; /* logical timestamp of a transactional update. + */ + uint8_t *new_hash; + uint8_t *old_hash; + char *name; + char *email; + uint64_t time; + int16_t tz_offset; + char *message; +}; + +/* returns whether 'ref' represents the deletion of a log record. */ +int reftable_log_record_is_deletion(const struct reftable_log_record *log); + +/* frees and nulls all pointer values. */ +void reftable_log_record_clear(struct reftable_log_record *log); + +/* returns whether two records are equal. */ +int reftable_log_record_equal(struct reftable_log_record *a, + struct reftable_log_record *b, int hash_size); + +/* dumps a reftable_log_record on stdout, for debugging/testing. */ +void reftable_log_record_print(struct reftable_log_record *log, + uint32_t hash_id); + +/**************************************************************** + Error handling + + Error are signaled with negative integer return values. 0 means success. + ****************************************************************/ + +/* different types of errors */ +enum reftable_error { + /* Unexpected file system behavior */ + REFTABLE_IO_ERROR = -2, + + /* Format inconsistency on reading data + */ + REFTABLE_FORMAT_ERROR = -3, + + /* File does not exist. Returned from block_source_from_file(), because + it needs special handling in stack. + */ + REFTABLE_NOT_EXIST_ERROR = -4, + + /* Trying to write out-of-date data. */ + REFTABLE_LOCK_ERROR = -5, + + /* Misuse of the API: + - on writing a record with NULL ref_name. + - on writing a reftable_ref_record outside the table limits + - on writing a ref or log record before the stack's next_update_index + - on writing a log record with multiline message with + exact_log_message unset + - on reading a reftable_ref_record from log iterator, or vice versa. + */ + REFTABLE_API_ERROR = -6, + + /* Decompression error */ + REFTABLE_ZLIB_ERROR = -7, + + /* Wrote a table without blocks. */ + REFTABLE_EMPTY_TABLE_ERROR = -8, + + /* Dir/file conflict. */ + REFTABLE_NAME_CONFLICT = -9, + + /* Illegal ref name. */ + REFTABLE_REFNAME_ERROR = -10, +}; + +/* convert the numeric error code to a string. The string should not be + * deallocated. */ +const char *reftable_error_str(int err); + +/* + * Convert the numeric error code to an equivalent errno code. + */ +int reftable_error_to_errno(int err); + +/**************************************************************** + Writing + + Writing single reftables + ****************************************************************/ + +/* reftable_write_options sets options for writing a single reftable. */ +struct reftable_write_options { + /* boolean: do not pad out blocks to block size. */ + int unpadded; + + /* the blocksize. Should be less than 2^24. */ + uint32_t block_size; + + /* boolean: do not generate a SHA1 => ref index. */ + int skip_index_objects; + + /* how often to write complete keys in each block. */ + int restart_interval; + + /* 4-byte identifier ("sha1", "s256") of the hash. + * Defaults to SHA1 if unset + */ + uint32_t hash_id; + + /* boolean: do not check ref names for validity or dir/file conflicts. + */ + int skip_name_check; + + /* boolean: copy log messages exactly. If unset, check that the message + * is a single line, and add '\n' if missing. + */ + int exact_log_message; +}; + +/* reftable_block_stats holds statistics for a single block type */ +struct reftable_block_stats { + /* total number of entries written */ + int entries; + /* total number of key restarts */ + int restarts; + /* total number of blocks */ + int blocks; + /* total number of index blocks */ + int index_blocks; + /* depth of the index */ + int max_index_level; + + /* offset of the first block for this type */ + uint64_t offset; + /* offset of the top level index block for this type, or 0 if not + * present */ + uint64_t index_offset; +}; + +/* stats holds overall statistics for a single reftable */ +struct reftable_stats { + /* total number of blocks written. */ + int blocks; + /* stats for ref data */ + struct reftable_block_stats ref_stats; + /* stats for the SHA1 to ref map. */ + struct reftable_block_stats obj_stats; + /* stats for index blocks */ + struct reftable_block_stats idx_stats; + /* stats for log blocks */ + struct reftable_block_stats log_stats; + + /* disambiguation length of shortened object IDs. */ + int object_id_len; +}; + +/* reftable_new_writer creates a new writer */ +struct reftable_writer * +reftable_new_writer(int (*writer_func)(void *, const void *, size_t), + void *writer_arg, struct reftable_write_options *opts); + +/* write to a file descriptor. fdp should be an int* pointing to the fd. */ +int reftable_fd_write(void *fdp, const void *data, size_t size); + +/* Set the range of update indices for the records we will add. When + writing a table into a stack, the min should be at least + reftable_stack_next_update_index(), or REFTABLE_API_ERROR is returned. + + For transactional updates, typically min==max. When converting an existing + ref database into a single reftable, this would be a range of update-index + timestamps. + */ +void reftable_writer_set_limits(struct reftable_writer *w, uint64_t min, + uint64_t max); + +/* adds a reftable_ref_record. Must be called in ascending + order. The update_index must be within the limits set by + reftable_writer_set_limits(), or REFTABLE_API_ERROR is returned. + + It is an error to write a ref record after a log record. + */ +int reftable_writer_add_ref(struct reftable_writer *w, + struct reftable_ref_record *ref); + +/* Convenience function to add multiple refs. Will sort the refs by + name before adding. */ +int reftable_writer_add_refs(struct reftable_writer *w, + struct reftable_ref_record *refs, int n); + +/* adds a reftable_log_record. Must be called in ascending order (with more + recent log entries first.) + */ +int reftable_writer_add_log(struct reftable_writer *w, + struct reftable_log_record *log); + +/* Convenience function to add multiple logs. Will sort the records by + key before adding. */ +int reftable_writer_add_logs(struct reftable_writer *w, + struct reftable_log_record *logs, int n); + +/* reftable_writer_close finalizes the reftable. The writer is retained so + * statistics can be inspected. */ +int reftable_writer_close(struct reftable_writer *w); + +/* writer_stats returns the statistics on the reftable being written. + + This struct becomes invalid when the writer is freed. + */ +const struct reftable_stats *writer_stats(struct reftable_writer *w); + +/* reftable_writer_free deallocates memory for the writer */ +void reftable_writer_free(struct reftable_writer *w); + +/**************************************************************** + * ITERATING + ****************************************************************/ + +/* iterator is the generic interface for walking over data stored in a + reftable. It is generally passed around by value. +*/ +struct reftable_iterator { + struct reftable_iterator_vtable *ops; + void *iter_arg; +}; + +/* reads the next reftable_ref_record. Returns < 0 for error, 0 for OK and > 0: + end of iteration. +*/ +int reftable_iterator_next_ref(struct reftable_iterator *it, + struct reftable_ref_record *ref); + +/* reads the next reftable_log_record. Returns < 0 for error, 0 for OK and > 0: + end of iteration. +*/ +int reftable_iterator_next_log(struct reftable_iterator *it, + struct reftable_log_record *log); + +/* releases resources associated with an iterator. */ +void reftable_iterator_destroy(struct reftable_iterator *it); + +/**************************************************************** + Reading single tables + + The follow routines are for reading single files. For an application-level + interface, skip ahead to struct reftable_merged_table and struct + reftable_stack. + ****************************************************************/ + +/* block_source is a generic wrapper for a seekable readable file. + It is generally passed around by value. + */ +struct reftable_block_source { + struct reftable_block_source_vtable *ops; + void *arg; +}; + +/* a contiguous segment of bytes. It keeps track of its generating block_source + so it can return itself into the pool. +*/ +struct reftable_block { + uint8_t *data; + int len; + struct reftable_block_source source; +}; + +/* block_source_vtable are the operations that make up block_source */ +struct reftable_block_source_vtable { + /* returns the size of a block source */ + uint64_t (*size)(void *source); + + /* reads a segment from the block source. It is an error to read + beyond the end of the block */ + int (*read_block)(void *source, struct reftable_block *dest, + uint64_t off, uint32_t size); + /* mark the block as read; may return the data back to malloc */ + void (*return_block)(void *source, struct reftable_block *blockp); + + /* release all resources associated with the block source */ + void (*close)(void *source); +}; + +/* opens a file on the file system as a block_source */ +int reftable_block_source_from_file(struct reftable_block_source *block_src, + const char *name); + +/* The reader struct is a handle to an open reftable file. */ +struct reftable_reader; + +/* reftable_new_reader opens a reftable for reading. If successful, returns 0 + * code and sets pp. The name is used for creating a stack. Typically, it is the + * basename of the file. The block source `src` is owned by the reader, and is + * closed on calling reftable_reader_destroy(). + */ +int reftable_new_reader(struct reftable_reader **pp, + struct reftable_block_source *src, const char *name); + +/* reftable_reader_seek_ref returns an iterator where 'name' would be inserted + in the table. To seek to the start of the table, use name = "". + + example: + + struct reftable_reader *r = NULL; + int err = reftable_new_reader(&r, &src, "filename"); + if (err < 0) { ... } + struct reftable_iterator it = {0}; + err = reftable_reader_seek_ref(r, &it, "refs/heads/master"); + if (err < 0) { ... } + struct reftable_ref_record ref = {0}; + while (1) { + err = reftable_iterator_next_ref(&it, &ref); + if (err > 0) { + break; + } + if (err < 0) { + ..error handling.. + } + ..found.. + } + reftable_iterator_destroy(&it); + reftable_ref_record_clear(&ref); + */ +int reftable_reader_seek_ref(struct reftable_reader *r, + struct reftable_iterator *it, const char *name); + +/* returns the hash ID used in this table. */ +uint32_t reftable_reader_hash_id(struct reftable_reader *r); + +/* seek to logs for the given name, older than update_index. To seek to the + start of the table, use name = "". + */ +int reftable_reader_seek_log_at(struct reftable_reader *r, + struct reftable_iterator *it, const char *name, + uint64_t update_index); + +/* seek to newest log entry for given name. */ +int reftable_reader_seek_log(struct reftable_reader *r, + struct reftable_iterator *it, const char *name); + +/* closes and deallocates a reader. */ +void reftable_reader_free(struct reftable_reader *); + +/* return an iterator for the refs pointing to `oid`. */ +int reftable_reader_refs_for(struct reftable_reader *r, + struct reftable_iterator *it, uint8_t *oid); + +/* return the max_update_index for a table */ +uint64_t reftable_reader_max_update_index(struct reftable_reader *r); + +/* return the min_update_index for a table */ +uint64_t reftable_reader_min_update_index(struct reftable_reader *r); + +/**************************************************************** + Merged tables + + A ref database kept in a sequence of table files. The merged_table presents a + unified view to reading (seeking, iterating) a sequence of immutable tables. + ****************************************************************/ + +/* A merged table is implements seeking/iterating over a stack of tables. */ +struct reftable_merged_table; + +/* reftable_new_merged_table creates a new merged table. It takes ownership of + the stack array. +*/ +int reftable_new_merged_table(struct reftable_merged_table **dest, + struct reftable_reader **stack, int n, + uint32_t hash_id); + +/* returns an iterator positioned just before 'name' */ +int reftable_merged_table_seek_ref(struct reftable_merged_table *mt, + struct reftable_iterator *it, + const char *name); + +/* returns an iterator for log entry, at given update_index */ +int reftable_merged_table_seek_log_at(struct reftable_merged_table *mt, + struct reftable_iterator *it, + const char *name, uint64_t update_index); + +/* like reftable_merged_table_seek_log_at but look for the newest entry. */ +int reftable_merged_table_seek_log(struct reftable_merged_table *mt, + struct reftable_iterator *it, + const char *name); + +/* returns the max update_index covered by this merged table. */ +uint64_t +reftable_merged_table_max_update_index(struct reftable_merged_table *mt); + +/* returns the min update_index covered by this merged table. */ +uint64_t +reftable_merged_table_min_update_index(struct reftable_merged_table *mt); + +/* closes readers for the merged tables */ +void reftable_merged_table_close(struct reftable_merged_table *mt); + +/* releases memory for the merged_table */ +void reftable_merged_table_free(struct reftable_merged_table *m); + +/**************************************************************** + Generic tables + + A unified API for reading tables, either merged tables, or single readers. + ****************************************************************/ + +struct reftable_table { + struct reftable_table_vtable *ops; + void *table_arg; +}; + +int reftable_table_seek_ref(struct reftable_table *tab, + struct reftable_iterator *it, const char *name); + +void reftable_table_from_reader(struct reftable_table *tab, + struct reftable_reader *reader); +void reftable_table_from_merged_table(struct reftable_table *tab, + struct reftable_merged_table *table); + +/* convenience function to read a single ref. Returns < 0 for error, 0 + for success, and 1 if ref not found. */ +int reftable_table_read_ref(struct reftable_table *tab, const char *name, + struct reftable_ref_record *ref); + +/**************************************************************** + Mutable ref database + + The stack presents an interface to a mutable sequence of reftables. + ****************************************************************/ + +/* a stack is a stack of reftables, which can be mutated by pushing a table to + * the top of the stack */ +struct reftable_stack; + +/* open a new reftable stack. The tables along with the table list will be + stored in 'dir'. Typically, this should be .git/reftables. +*/ +int reftable_new_stack(struct reftable_stack **dest, const char *dir, + struct reftable_write_options config); + +/* returns the update_index at which a next table should be written. */ +uint64_t reftable_stack_next_update_index(struct reftable_stack *st); + +/* holds a transaction to add tables at the top of a stack. */ +struct reftable_addition; + +/* + returns a new transaction to add reftables to the given stack. As a side + effect, the ref database is locked. +*/ +int reftable_stack_new_addition(struct reftable_addition **dest, + struct reftable_stack *st); + +/* Adds a reftable to transaction. */ +int reftable_addition_add(struct reftable_addition *add, + int (*write_table)(struct reftable_writer *wr, + void *arg), + void *arg); + +/* Commits the transaction, releasing the lock. */ +int reftable_addition_commit(struct reftable_addition *add); + +/* Release all non-committed data from the transaction, and deallocate the + transaction. Releases the lock if held. */ +void reftable_addition_destroy(struct reftable_addition *add); + +/* add a new table to the stack. The write_table function must call + reftable_writer_set_limits, add refs and return an error value. */ +int reftable_stack_add(struct reftable_stack *st, + int (*write_table)(struct reftable_writer *wr, + void *write_arg), + void *write_arg); + +/* returns the merged_table for seeking. This table is valid until the + next write or reload, and should not be closed or deleted. +*/ +struct reftable_merged_table * +reftable_stack_merged_table(struct reftable_stack *st); + +/* frees all resources associated with the stack. */ +void reftable_stack_destroy(struct reftable_stack *st); + +/* Reloads the stack if necessary. This is very cheap to run if the stack was up + * to date */ +int reftable_stack_reload(struct reftable_stack *st); + +/* Policy for expiring reflog entries. */ +struct reftable_log_expiry_config { + /* Drop entries older than this timestamp */ + uint64_t time; + + /* Drop older entries */ + uint64_t min_update_index; +}; + +/* compacts all reftables into a giant table. Expire reflog entries if config is + * non-NULL */ +int reftable_stack_compact_all(struct reftable_stack *st, + struct reftable_log_expiry_config *config); + +/* heuristically compact unbalanced table stack. */ +int reftable_stack_auto_compact(struct reftable_stack *st); + +/* convenience function to read a single ref. Returns < 0 for error, 0 + for success, and 1 if ref not found. */ +int reftable_stack_read_ref(struct reftable_stack *st, const char *refname, + struct reftable_ref_record *ref); + +/* convenience function to read a single log. Returns < 0 for error, 0 + for success, and 1 if ref not found. */ +int reftable_stack_read_log(struct reftable_stack *st, const char *refname, + struct reftable_log_record *log); + +/* statistics on past compactions. */ +struct reftable_compaction_stats { + uint64_t bytes; /* total number of bytes written */ + uint64_t entries_written; /* total number of entries written, including + failures. */ + int attempts; /* how often we tried to compact */ + int failures; /* failures happen on concurrent updates */ +}; + +/* return statistics for compaction up till now. */ +struct reftable_compaction_stats * +reftable_stack_compaction_stats(struct reftable_stack *st); + +#endif diff --git a/reftable/reftable_test.c b/reftable/reftable_test.c new file mode 100644 index 00000000000..3b598a56f1a --- /dev/null +++ b/reftable/reftable_test.c @@ -0,0 +1,631 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "reftable.h" + +#include "system.h" + +#include "basics.h" +#include "block.h" +#include "constants.h" +#include "reader.h" +#include "record.h" +#include "test_framework.h" +#include "reftable-tests.h" + +static const int update_index = 5; + +static void test_buffer(void) +{ + struct strbuf buf = STRBUF_INIT; + struct reftable_block_source source = { NULL }; + struct reftable_block out = { 0 }; + int n; + uint8_t in[] = "hello"; + strbuf_add(&buf, in, sizeof(in)); + block_source_from_strbuf(&source, &buf); + assert(block_source_size(&source) == 6); + n = block_source_read_block(&source, &out, 0, sizeof(in)); + assert(n == sizeof(in)); + assert(!memcmp(in, out.data, n)); + reftable_block_done(&out); + + n = block_source_read_block(&source, &out, 1, 2); + assert(n == 2); + assert(!memcmp(out.data, "el", 2)); + + reftable_block_done(&out); + block_source_close(&source); + strbuf_release(&buf); +} + +static void test_default_write_opts(void) +{ + struct reftable_write_options opts = { 0 }; + struct strbuf buf = STRBUF_INIT; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + + struct reftable_ref_record rec = { + .ref_name = "master", + .update_index = 1, + }; + int err; + struct reftable_block_source source = { 0 }; + struct reftable_reader **readers = malloc(sizeof(*readers) * 1); + uint32_t hash_id; + struct reftable_reader *rd = NULL; + struct reftable_merged_table *merged = NULL; + + reftable_writer_set_limits(w, 1, 1); + + err = reftable_writer_add_ref(w, &rec); + assert_err(err); + + err = reftable_writer_close(w); + assert_err(err); + reftable_writer_free(w); + + block_source_from_strbuf(&source, &buf); + + err = reftable_new_reader(&rd, &source, "filename"); + assert_err(err); + + hash_id = reftable_reader_hash_id(rd); + assert(hash_id == SHA1_ID); + + readers[0] = rd; + + err = reftable_new_merged_table(&merged, readers, 1, SHA1_ID); + assert_err(err); + + reftable_merged_table_close(merged); + reftable_merged_table_free(merged); + strbuf_release(&buf); +} + +static void write_table(char ***names, struct strbuf *buf, int N, + int block_size, uint32_t hash_id) +{ + struct reftable_write_options opts = { + .block_size = block_size, + .hash_id = hash_id, + }; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, buf, &opts); + struct reftable_ref_record ref = { 0 }; + int i = 0, n; + struct reftable_log_record log = { 0 }; + const struct reftable_stats *stats = NULL; + *names = reftable_calloc(sizeof(char *) * (N + 1)); + reftable_writer_set_limits(w, update_index, update_index); + for (i = 0; i < N; i++) { + uint8_t hash[SHA256_SIZE] = { 0 }; + char name[100]; + int n; + + set_test_hash(hash, i); + + snprintf(name, sizeof(name), "refs/heads/branch%02d", i); + + ref.ref_name = name; + ref.value = hash; + ref.update_index = update_index; + (*names)[i] = xstrdup(name); + + n = reftable_writer_add_ref(w, &ref); + assert(n == 0); + } + + for (i = 0; i < N; i++) { + uint8_t hash[SHA256_SIZE] = { 0 }; + char name[100]; + int n; + + set_test_hash(hash, i); + + snprintf(name, sizeof(name), "refs/heads/branch%02d", i); + + log.ref_name = name; + log.new_hash = hash; + log.update_index = update_index; + log.message = "message"; + + n = reftable_writer_add_log(w, &log); + assert(n == 0); + } + + n = reftable_writer_close(w); + assert(n == 0); + + stats = writer_stats(w); + for (i = 0; i < stats->ref_stats.blocks; i++) { + int off = i * opts.block_size; + if (off == 0) { + off = header_size((hash_id == SHA256_ID) ? 2 : 1); + } + assert(buf->buf[off] == 'r'); + } + + assert(stats->log_stats.blocks > 0); + reftable_writer_free(w); +} + +static void test_log_buffer_size(void) +{ + struct strbuf buf = STRBUF_INIT; + struct reftable_write_options opts = { + .block_size = 4096, + }; + int err; + struct reftable_log_record log = { + .ref_name = "refs/heads/master", + .name = "Han-Wen Nienhuys", + .email = "hanwen@xxxxxxxxxx", + .tz_offset = 100, + .time = 0x5e430672, + .update_index = 0xa, + .message = "commit: 9\n", + }; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + + /* This tests buffer extension for log compression. Must use a random + hash, to ensure that the compressed part is larger than the original. + */ + uint8_t hash1[SHA1_SIZE], hash2[SHA1_SIZE]; + for (int i = 0; i < SHA1_SIZE; i++) { + hash1[i] = (uint8_t)(rand() % 256); + hash2[i] = (uint8_t)(rand() % 256); + } + log.old_hash = hash1; + log.new_hash = hash2; + reftable_writer_set_limits(w, update_index, update_index); + err = reftable_writer_add_log(w, &log); + assert_err(err); + err = reftable_writer_close(w); + assert_err(err); + reftable_writer_free(w); + strbuf_release(&buf); +} + +static void test_log_write_read(void) +{ + int N = 2; + char **names = reftable_calloc(sizeof(char *) * (N + 1)); + int err; + struct reftable_write_options opts = { + .block_size = 256, + }; + struct reftable_ref_record ref = { 0 }; + int i = 0; + struct reftable_log_record log = { 0 }; + int n; + struct reftable_iterator it = { 0 }; + struct reftable_reader rd = { 0 }; + struct reftable_block_source source = { 0 }; + struct strbuf buf = STRBUF_INIT; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + const struct reftable_stats *stats = NULL; + reftable_writer_set_limits(w, 0, N); + for (i = 0; i < N; i++) { + char name[256]; + struct reftable_ref_record ref = { 0 }; + snprintf(name, sizeof(name), "b%02d%0*d", i, 130, 7); + names[i] = xstrdup(name); + puts(name); + ref.ref_name = name; + ref.update_index = i; + + err = reftable_writer_add_ref(w, &ref); + assert_err(err); + } + for (i = 0; i < N; i++) { + uint8_t hash1[SHA1_SIZE], hash2[SHA1_SIZE]; + struct reftable_log_record log = { 0 }; + set_test_hash(hash1, i); + set_test_hash(hash2, i + 1); + + log.ref_name = names[i]; + log.update_index = i; + log.old_hash = hash1; + log.new_hash = hash2; + + err = reftable_writer_add_log(w, &log); + assert_err(err); + } + + n = reftable_writer_close(w); + assert(n == 0); + + stats = writer_stats(w); + assert(stats->log_stats.blocks > 0); + reftable_writer_free(w); + w = NULL; + + block_source_from_strbuf(&source, &buf); + + err = init_reader(&rd, &source, "file.log"); + assert_err(err); + + err = reftable_reader_seek_ref(&rd, &it, names[N - 1]); + assert_err(err); + + err = reftable_iterator_next_ref(&it, &ref); + assert_err(err); + + /* end of iteration. */ + err = reftable_iterator_next_ref(&it, &ref); + assert(0 < err); + + reftable_iterator_destroy(&it); + reftable_ref_record_clear(&ref); + + err = reftable_reader_seek_log(&rd, &it, ""); + assert_err(err); + + i = 0; + while (true) { + int err = reftable_iterator_next_log(&it, &log); + if (err > 0) { + break; + } + + assert_err(err); + assert_streq(names[i], log.ref_name); + assert(i == log.update_index); + i++; + reftable_log_record_clear(&log); + } + + assert(i == N); + reftable_iterator_destroy(&it); + + /* cleanup. */ + strbuf_release(&buf); + free_names(names); + reader_close(&rd); +} + +static void test_table_read_write_sequential(void) +{ + char **names; + struct strbuf buf = STRBUF_INIT; + int N = 50; + struct reftable_iterator it = { 0 }; + struct reftable_block_source source = { 0 }; + struct reftable_reader rd = { 0 }; + int err = 0; + int j = 0; + + write_table(&names, &buf, N, 256, SHA1_ID); + + block_source_from_strbuf(&source, &buf); + + err = init_reader(&rd, &source, "file.ref"); + assert_err(err); + + err = reftable_reader_seek_ref(&rd, &it, ""); + assert_err(err); + + while (true) { + struct reftable_ref_record ref = { 0 }; + int r = reftable_iterator_next_ref(&it, &ref); + assert(r >= 0); + if (r > 0) { + break; + } + assert(0 == strcmp(names[j], ref.ref_name)); + assert(update_index == ref.update_index); + + j++; + reftable_ref_record_clear(&ref); + } + assert(j == N); + reftable_iterator_destroy(&it); + strbuf_release(&buf); + free_names(names); + + reader_close(&rd); +} + +static void test_table_write_small_table(void) +{ + char **names; + struct strbuf buf = STRBUF_INIT; + int N = 1; + write_table(&names, &buf, N, 4096, SHA1_ID); + assert(buf.len < 200); + strbuf_release(&buf); + free_names(names); +} + +static void test_table_read_api(void) +{ + char **names; + struct strbuf buf = STRBUF_INIT; + int N = 50; + struct reftable_reader rd = { 0 }; + struct reftable_block_source source = { 0 }; + int err; + int i; + struct reftable_log_record log = { 0 }; + struct reftable_iterator it = { 0 }; + + write_table(&names, &buf, N, 256, SHA1_ID); + + block_source_from_strbuf(&source, &buf); + + err = init_reader(&rd, &source, "file.ref"); + assert_err(err); + + err = reftable_reader_seek_ref(&rd, &it, names[0]); + assert_err(err); + + err = reftable_iterator_next_log(&it, &log); + assert(err == REFTABLE_API_ERROR); + + strbuf_release(&buf); + for (i = 0; i < N; i++) { + reftable_free(names[i]); + } + reftable_iterator_destroy(&it); + reftable_free(names); + reader_close(&rd); + strbuf_release(&buf); +} + +static void test_table_read_write_seek(bool index, int hash_id) +{ + char **names; + struct strbuf buf = STRBUF_INIT; + int N = 50; + struct reftable_reader rd = { 0 }; + struct reftable_block_source source = { 0 }; + int err; + int i = 0; + + struct reftable_iterator it = { 0 }; + struct strbuf pastLast = STRBUF_INIT; + struct reftable_ref_record ref = { 0 }; + + write_table(&names, &buf, N, 256, hash_id); + + block_source_from_strbuf(&source, &buf); + + err = init_reader(&rd, &source, "file.ref"); + assert_err(err); + assert(hash_id == reftable_reader_hash_id(&rd)); + + if (!index) { + rd.ref_offsets.index_offset = 0; + } else { + assert(rd.ref_offsets.index_offset > 0); + } + + for (i = 1; i < N; i++) { + int err = reftable_reader_seek_ref(&rd, &it, names[i]); + assert_err(err); + err = reftable_iterator_next_ref(&it, &ref); + assert_err(err); + assert(0 == strcmp(names[i], ref.ref_name)); + assert(i == ref.value[0]); + + reftable_ref_record_clear(&ref); + reftable_iterator_destroy(&it); + } + + strbuf_addstr(&pastLast, names[N - 1]); + strbuf_addstr(&pastLast, "/"); + + err = reftable_reader_seek_ref(&rd, &it, pastLast.buf); + if (err == 0) { + struct reftable_ref_record ref = { 0 }; + int err = reftable_iterator_next_ref(&it, &ref); + assert(err > 0); + } else { + assert(err > 0); + } + + strbuf_release(&pastLast); + reftable_iterator_destroy(&it); + + strbuf_release(&buf); + for (i = 0; i < N; i++) { + reftable_free(names[i]); + } + reftable_free(names); + reader_close(&rd); +} + +static void test_table_read_write_seek_linear(void) +{ + test_table_read_write_seek(false, SHA1_ID); +} + +static void test_table_read_write_seek_linear_sha256(void) +{ + test_table_read_write_seek(false, SHA256_ID); +} + +static void test_table_read_write_seek_index(void) +{ + test_table_read_write_seek(true, SHA1_ID); +} + +static void test_table_refs_for(bool indexed) +{ + int N = 50; + char **want_names = reftable_calloc(sizeof(char *) * (N + 1)); + int want_names_len = 0; + uint8_t want_hash[SHA1_SIZE]; + + struct reftable_write_options opts = { + .block_size = 256, + }; + struct reftable_ref_record ref = { 0 }; + int i = 0; + int n; + int err; + struct reftable_reader rd; + struct reftable_block_source source = { 0 }; + + struct strbuf buf = STRBUF_INIT; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + + struct reftable_iterator it = { 0 }; + int j; + + set_test_hash(want_hash, 4); + + for (i = 0; i < N; i++) { + uint8_t hash[SHA1_SIZE]; + char fill[51] = { 0 }; + char name[100]; + uint8_t hash1[SHA1_SIZE]; + uint8_t hash2[SHA1_SIZE]; + struct reftable_ref_record ref = { 0 }; + + memset(hash, i, sizeof(hash)); + memset(fill, 'x', 50); + /* Put the variable part in the start */ + snprintf(name, sizeof(name), "br%02d%s", i, fill); + name[40] = 0; + ref.ref_name = name; + + set_test_hash(hash1, i / 4); + set_test_hash(hash2, 3 + i / 4); + ref.value = hash1; + ref.target_value = hash2; + + /* 80 bytes / entry, so 3 entries per block. Yields 17 + */ + /* blocks. */ + n = reftable_writer_add_ref(w, &ref); + assert(n == 0); + + if (!memcmp(hash1, want_hash, SHA1_SIZE) || + !memcmp(hash2, want_hash, SHA1_SIZE)) { + want_names[want_names_len++] = xstrdup(name); + } + } + + n = reftable_writer_close(w); + assert(n == 0); + + reftable_writer_free(w); + w = NULL; + + block_source_from_strbuf(&source, &buf); + + err = init_reader(&rd, &source, "file.ref"); + assert_err(err); + if (!indexed) { + rd.obj_offsets.present = 0; + } + + err = reftable_reader_seek_ref(&rd, &it, ""); + assert_err(err); + reftable_iterator_destroy(&it); + + err = reftable_reader_refs_for(&rd, &it, want_hash); + assert_err(err); + + j = 0; + while (true) { + int err = reftable_iterator_next_ref(&it, &ref); + assert(err >= 0); + if (err > 0) { + break; + } + + assert(j < want_names_len); + assert(0 == strcmp(ref.ref_name, want_names[j])); + j++; + reftable_ref_record_clear(&ref); + } + assert(j == want_names_len); + + strbuf_release(&buf); + free_names(want_names); + reftable_iterator_destroy(&it); + reader_close(&rd); +} + +static void test_table_refs_for_no_index(void) +{ + test_table_refs_for(false); +} + +static void test_table_refs_for_obj_index(void) +{ + test_table_refs_for(true); +} + +static void test_table_empty(void) +{ + struct reftable_write_options opts = { 0 }; + struct strbuf buf = STRBUF_INIT; + struct reftable_writer *w = + reftable_new_writer(&strbuf_add_void, &buf, &opts); + struct reftable_block_source source = { 0 }; + struct reftable_reader *rd = NULL; + struct reftable_ref_record rec = { 0 }; + struct reftable_iterator it = { 0 }; + int err; + + reftable_writer_set_limits(w, 1, 1); + + err = reftable_writer_close(w); + assert(err == REFTABLE_EMPTY_TABLE_ERROR); + reftable_writer_free(w); + + assert(buf.len == header_size(1) + footer_size(1)); + + block_source_from_strbuf(&source, &buf); + + err = reftable_new_reader(&rd, &source, "filename"); + assert_err(err); + + err = reftable_reader_seek_ref(rd, &it, ""); + assert_err(err); + + err = reftable_iterator_next_ref(&it, &rec); + assert(err > 0); + + reftable_iterator_destroy(&it); + reftable_reader_free(rd); + strbuf_release(&buf); +} + +int reftable_test_main(int argc, const char *argv[]) +{ + add_test_case("test_default_write_opts", test_default_write_opts); + add_test_case("test_log_write_read", test_log_write_read); + add_test_case("test_table_read_write_seek_linear_sha256", + &test_table_read_write_seek_linear_sha256); + add_test_case("test_log_buffer_size", test_log_buffer_size); + add_test_case("test_table_write_small_table", + &test_table_write_small_table); + add_test_case("test_buffer", &test_buffer); + add_test_case("test_table_read_api", &test_table_read_api); + add_test_case("test_table_read_write_sequential", + &test_table_read_write_sequential); + add_test_case("test_table_read_write_seek_linear", + &test_table_read_write_seek_linear); + add_test_case("test_table_read_write_seek_index", + &test_table_read_write_seek_index); + add_test_case("test_table_read_write_refs_for_no_index", + &test_table_refs_for_no_index); + add_test_case("test_table_read_write_refs_for_obj_index", + &test_table_refs_for_obj_index); + add_test_case("test_table_empty", &test_table_empty); + return test_main(argc, argv); +} diff --git a/reftable/stack.c b/reftable/stack.c new file mode 100644 index 00000000000..fad12ae301f --- /dev/null +++ b/reftable/stack.c @@ -0,0 +1,1209 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "stack.h" + +#include "system.h" +#include "merged.h" +#include "reader.h" +#include "refname.h" +#include "reftable.h" +#include "writer.h" + +int reftable_new_stack(struct reftable_stack **dest, const char *dir, + struct reftable_write_options config) +{ + struct reftable_stack *p = + reftable_calloc(sizeof(struct reftable_stack)); + struct strbuf list_file_name = STRBUF_INIT; + int err = 0; + + if (config.hash_id == 0) { + config.hash_id = SHA1_ID; + } + + *dest = NULL; + + strbuf_reset(&list_file_name); + strbuf_addstr(&list_file_name, dir); + strbuf_addstr(&list_file_name, "/tables.list"); + + p->list_file = strbuf_detach(&list_file_name, NULL); + p->reftable_dir = xstrdup(dir); + p->config = config; + + err = reftable_stack_reload_maybe_reuse(p, true); + if (err < 0) { + reftable_stack_destroy(p); + } else { + *dest = p; + } + return err; +} + +static int fd_read_lines(int fd, char ***namesp) +{ + off_t size = lseek(fd, 0, SEEK_END); + char *buf = NULL; + int err = 0; + if (size < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + err = lseek(fd, 0, SEEK_SET); + if (err < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + + buf = reftable_malloc(size + 1); + if (read(fd, buf, size) != size) { + err = REFTABLE_IO_ERROR; + goto done; + } + buf[size] = 0; + + parse_names(buf, size, namesp); + +done: + reftable_free(buf); + return err; +} + +int read_lines(const char *filename, char ***namesp) +{ + int fd = open(filename, O_RDONLY, 0644); + int err = 0; + if (fd < 0) { + if (errno == ENOENT) { + *namesp = reftable_calloc(sizeof(char *)); + return 0; + } + + return REFTABLE_IO_ERROR; + } + err = fd_read_lines(fd, namesp); + close(fd); + return err; +} + +struct reftable_merged_table * +reftable_stack_merged_table(struct reftable_stack *st) +{ + return st->merged; +} + +/* Close and free the stack */ +void reftable_stack_destroy(struct reftable_stack *st) +{ + if (st->merged != NULL) { + reftable_merged_table_close(st->merged); + reftable_merged_table_free(st->merged); + st->merged = NULL; + } + FREE_AND_NULL(st->list_file); + FREE_AND_NULL(st->reftable_dir); + reftable_free(st); +} + +static struct reftable_reader **stack_copy_readers(struct reftable_stack *st, + int cur_len) +{ + struct reftable_reader **cur = + reftable_calloc(sizeof(struct reftable_reader *) * cur_len); + int i = 0; + for (i = 0; i < cur_len; i++) { + cur[i] = st->merged->stack[i]; + } + return cur; +} + +static int reftable_stack_reload_once(struct reftable_stack *st, char **names, + bool reuse_open) +{ + int cur_len = st->merged == NULL ? 0 : st->merged->stack_len; + struct reftable_reader **cur = stack_copy_readers(st, cur_len); + int err = 0; + int names_len = names_length(names); + struct reftable_reader **new_tables = + reftable_malloc(sizeof(struct reftable_reader *) * names_len); + int new_tables_len = 0; + struct reftable_merged_table *new_merged = NULL; + int i; + + while (*names) { + struct reftable_reader *rd = NULL; + char *name = *names++; + + /* this is linear; we assume compaction keeps the number of + tables under control so this is not quadratic. */ + int j = 0; + for (j = 0; reuse_open && j < cur_len; j++) { + if (cur[j] != NULL && 0 == strcmp(cur[j]->name, name)) { + rd = cur[j]; + cur[j] = NULL; + break; + } + } + + if (rd == NULL) { + struct reftable_block_source src = { 0 }; + struct strbuf table_path = STRBUF_INIT; + strbuf_addstr(&table_path, st->reftable_dir); + strbuf_addstr(&table_path, "/"); + strbuf_addstr(&table_path, name); + + err = reftable_block_source_from_file(&src, + table_path.buf); + strbuf_release(&table_path); + + if (err < 0) + goto done; + + err = reftable_new_reader(&rd, &src, name); + if (err < 0) + goto done; + } + + new_tables[new_tables_len++] = rd; + } + + /* success! */ + err = reftable_new_merged_table(&new_merged, new_tables, new_tables_len, + st->config.hash_id); + if (err < 0) + goto done; + + new_tables = NULL; + new_tables_len = 0; + if (st->merged != NULL) { + merged_table_clear(st->merged); + reftable_merged_table_free(st->merged); + } + new_merged->suppress_deletions = true; + st->merged = new_merged; + + for (i = 0; i < cur_len; i++) { + if (cur[i] != NULL) { + reader_close(cur[i]); + reftable_reader_free(cur[i]); + } + } + +done: + for (i = 0; i < new_tables_len; i++) { + reader_close(new_tables[i]); + reftable_reader_free(new_tables[i]); + } + reftable_free(new_tables); + reftable_free(cur); + return err; +} + +/* return negative if a before b. */ +static int tv_cmp(struct timeval *a, struct timeval *b) +{ + time_t diff = a->tv_sec - b->tv_sec; + int udiff = a->tv_usec - b->tv_usec; + + if (diff != 0) + return diff; + + return udiff; +} + +int reftable_stack_reload_maybe_reuse(struct reftable_stack *st, + bool reuse_open) +{ + struct timeval deadline = { 0 }; + int err = gettimeofday(&deadline, NULL); + int64_t delay = 0; + int tries = 0; + if (err < 0) + return err; + + deadline.tv_sec += 3; + while (true) { + char **names = NULL; + char **names_after = NULL; + struct timeval now = { 0 }; + int err = gettimeofday(&now, NULL); + int err2 = 0; + if (err < 0) { + return err; + } + + /* Only look at deadlines after the first few times. This + simplifies debugging in GDB */ + tries++; + if (tries > 3 && tv_cmp(&now, &deadline) >= 0) { + break; + } + + err = read_lines(st->list_file, &names); + if (err < 0) { + free_names(names); + return err; + } + err = reftable_stack_reload_once(st, names, reuse_open); + if (err == 0) { + free_names(names); + break; + } + if (err != REFTABLE_NOT_EXIST_ERROR) { + free_names(names); + return err; + } + + /* err == REFTABLE_NOT_EXIST_ERROR can be caused by a concurrent + writer. Check if there was one by checking if the name list + changed. + */ + err2 = read_lines(st->list_file, &names_after); + if (err2 < 0) { + free_names(names); + return err2; + } + + if (names_equal(names_after, names)) { + free_names(names); + free_names(names_after); + return err; + } + free_names(names); + free_names(names_after); + + delay = delay + (delay * rand()) / RAND_MAX + 1; + sleep_millisec(delay); + } + + return 0; +} + +/* -1 = error + 0 = up to date + 1 = changed. */ +static int stack_uptodate(struct reftable_stack *st) +{ + char **names = NULL; + int err = read_lines(st->list_file, &names); + int i = 0; + if (err < 0) + return err; + + for (i = 0; i < st->merged->stack_len; i++) { + if (names[i] == NULL) { + err = 1; + goto done; + } + + if (strcmp(st->merged->stack[i]->name, names[i])) { + err = 1; + goto done; + } + } + + if (names[st->merged->stack_len] != NULL) { + err = 1; + goto done; + } + +done: + free_names(names); + return err; +} + +int reftable_stack_reload(struct reftable_stack *st) +{ + int err = stack_uptodate(st); + if (err > 0) + return reftable_stack_reload_maybe_reuse(st, true); + return err; +} + +int reftable_stack_add(struct reftable_stack *st, + int (*write)(struct reftable_writer *wr, void *arg), + void *arg) +{ + int err = stack_try_add(st, write, arg); + if (err < 0) { + if (err == REFTABLE_LOCK_ERROR) { + /* Ignore error return, we want to propagate + REFTABLE_LOCK_ERROR. + */ + reftable_stack_reload(st); + } + return err; + } + + if (!st->disable_auto_compact) + return reftable_stack_auto_compact(st); + + return 0; +} + +static void format_name(struct strbuf *dest, uint64_t min, uint64_t max) +{ + char buf[100]; + snprintf(buf, sizeof(buf), "0x%012" PRIx64 "-0x%012" PRIx64, min, max); + strbuf_reset(dest); + strbuf_addstr(dest, buf); +} + +struct reftable_addition { + int lock_file_fd; + struct strbuf lock_file_name; + struct reftable_stack *stack; + char **names; + char **new_tables; + int new_tables_len; + uint64_t next_update_index; +}; + +#define REFTABLE_ADDITION_INIT \ + { \ + .lock_file_name = STRBUF_INIT \ + } + +static int reftable_stack_init_addition(struct reftable_addition *add, + struct reftable_stack *st) +{ + int err = 0; + add->stack = st; + + strbuf_reset(&add->lock_file_name); + strbuf_addstr(&add->lock_file_name, st->list_file); + strbuf_addstr(&add->lock_file_name, ".lock"); + + add->lock_file_fd = open(add->lock_file_name.buf, + O_EXCL | O_CREAT | O_WRONLY, 0644); + if (add->lock_file_fd < 0) { + if (errno == EEXIST) { + err = REFTABLE_LOCK_ERROR; + } else { + err = REFTABLE_IO_ERROR; + } + goto done; + } + err = stack_uptodate(st); + if (err < 0) + goto done; + + if (err > 1) { + err = REFTABLE_LOCK_ERROR; + goto done; + } + + add->next_update_index = reftable_stack_next_update_index(st); +done: + if (err) { + reftable_addition_close(add); + } + return err; +} + +void reftable_addition_close(struct reftable_addition *add) +{ + int i = 0; + struct strbuf nm = STRBUF_INIT; + for (i = 0; i < add->new_tables_len; i++) { + strbuf_reset(&nm); + strbuf_addstr(&nm, add->stack->list_file); + strbuf_addstr(&nm, "/"); + strbuf_addstr(&nm, add->new_tables[i]); + unlink(nm.buf); + reftable_free(add->new_tables[i]); + add->new_tables[i] = NULL; + } + reftable_free(add->new_tables); + add->new_tables = NULL; + add->new_tables_len = 0; + + if (add->lock_file_fd > 0) { + close(add->lock_file_fd); + add->lock_file_fd = 0; + } + if (add->lock_file_name.len > 0) { + unlink(add->lock_file_name.buf); + strbuf_release(&add->lock_file_name); + } + + free_names(add->names); + add->names = NULL; + strbuf_release(&nm); +} + +void reftable_addition_destroy(struct reftable_addition *add) +{ + if (add == NULL) { + return; + } + reftable_addition_close(add); + reftable_free(add); +} + +int reftable_addition_commit(struct reftable_addition *add) +{ + struct strbuf table_list = STRBUF_INIT; + int i = 0; + int err = 0; + if (add->new_tables_len == 0) + goto done; + + for (i = 0; i < add->stack->merged->stack_len; i++) { + strbuf_addstr(&table_list, add->stack->merged->stack[i]->name); + strbuf_addstr(&table_list, "\n"); + } + for (i = 0; i < add->new_tables_len; i++) { + strbuf_addstr(&table_list, add->new_tables[i]); + strbuf_addstr(&table_list, "\n"); + } + + err = write(add->lock_file_fd, table_list.buf, table_list.len); + strbuf_release(&table_list); + if (err < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + + err = close(add->lock_file_fd); + add->lock_file_fd = 0; + if (err < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + + err = rename(add->lock_file_name.buf, add->stack->list_file); + if (err < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + + err = reftable_stack_reload(add->stack); + +done: + reftable_addition_close(add); + return err; +} + +int reftable_stack_new_addition(struct reftable_addition **dest, + struct reftable_stack *st) +{ + int err = 0; + struct reftable_addition empty = REFTABLE_ADDITION_INIT; + *dest = reftable_calloc(sizeof(**dest)); + **dest = empty; + err = reftable_stack_init_addition(*dest, st); + if (err) { + reftable_free(*dest); + *dest = NULL; + } + return err; +} + +int stack_try_add(struct reftable_stack *st, + int (*write_table)(struct reftable_writer *wr, void *arg), + void *arg) +{ + struct reftable_addition add = REFTABLE_ADDITION_INIT; + int err = reftable_stack_init_addition(&add, st); + if (err < 0) + goto done; + if (err > 0) { + err = REFTABLE_LOCK_ERROR; + goto done; + } + + err = reftable_addition_add(&add, write_table, arg); + if (err < 0) + goto done; + + err = reftable_addition_commit(&add); +done: + reftable_addition_close(&add); + return err; +} + +int reftable_addition_add(struct reftable_addition *add, + int (*write_table)(struct reftable_writer *wr, + void *arg), + void *arg) +{ + struct strbuf temp_tab_file_name = STRBUF_INIT; + struct strbuf tab_file_name = STRBUF_INIT; + struct strbuf next_name = STRBUF_INIT; + struct reftable_writer *wr = NULL; + int err = 0; + int tab_fd = 0; + + strbuf_reset(&next_name); + format_name(&next_name, add->next_update_index, add->next_update_index); + + strbuf_addstr(&temp_tab_file_name, add->stack->reftable_dir); + strbuf_addstr(&temp_tab_file_name, "/"); + strbuf_addbuf(&temp_tab_file_name, &next_name); + strbuf_addstr(&temp_tab_file_name, ".temp.XXXXXX"); + + tab_fd = mkstemp(temp_tab_file_name.buf); + if (tab_fd < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + + wr = reftable_new_writer(reftable_fd_write, &tab_fd, + &add->stack->config); + err = write_table(wr, arg); + if (err < 0) + goto done; + + err = reftable_writer_close(wr); + if (err == REFTABLE_EMPTY_TABLE_ERROR) { + err = 0; + goto done; + } + if (err < 0) + goto done; + + err = close(tab_fd); + tab_fd = 0; + if (err < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + + err = stack_check_addition(add->stack, temp_tab_file_name.buf); + if (err < 0) + goto done; + + if (wr->min_update_index < add->next_update_index) { + err = REFTABLE_API_ERROR; + goto done; + } + + format_name(&next_name, wr->min_update_index, wr->max_update_index); + strbuf_addstr(&next_name, ".ref"); + + strbuf_addstr(&tab_file_name, add->stack->reftable_dir); + strbuf_addstr(&tab_file_name, "/"); + strbuf_addbuf(&tab_file_name, &next_name); + + /* TODO: should check destination out of paranoia */ + err = rename(temp_tab_file_name.buf, tab_file_name.buf); + if (err < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + + add->new_tables = reftable_realloc(add->new_tables, + sizeof(*add->new_tables) * + (add->new_tables_len + 1)); + add->new_tables[add->new_tables_len] = strbuf_detach(&next_name, NULL); + add->new_tables_len++; +done: + if (tab_fd > 0) { + close(tab_fd); + tab_fd = 0; + } + if (temp_tab_file_name.len > 0) { + unlink(temp_tab_file_name.buf); + } + + strbuf_release(&temp_tab_file_name); + strbuf_release(&tab_file_name); + strbuf_release(&next_name); + reftable_writer_free(wr); + return err; +} + +uint64_t reftable_stack_next_update_index(struct reftable_stack *st) +{ + int sz = st->merged->stack_len; + if (sz > 0) + return reftable_reader_max_update_index( + st->merged->stack[sz - 1]) + + 1; + return 1; +} + +static int stack_compact_locked(struct reftable_stack *st, int first, int last, + struct strbuf *temp_tab, + struct reftable_log_expiry_config *config) +{ + struct strbuf next_name = STRBUF_INIT; + int tab_fd = -1; + struct reftable_writer *wr = NULL; + int err = 0; + + format_name(&next_name, + reftable_reader_min_update_index(st->merged->stack[first]), + reftable_reader_max_update_index(st->merged->stack[first])); + + strbuf_reset(temp_tab); + strbuf_addstr(temp_tab, st->reftable_dir); + strbuf_addstr(temp_tab, "/"); + strbuf_addbuf(temp_tab, &next_name); + strbuf_addstr(temp_tab, ".temp.XXXXXX"); + + tab_fd = mkstemp(temp_tab->buf); + wr = reftable_new_writer(reftable_fd_write, &tab_fd, &st->config); + + err = stack_write_compact(st, wr, first, last, config); + if (err < 0) + goto done; + err = reftable_writer_close(wr); + if (err < 0) + goto done; + + err = close(tab_fd); + tab_fd = 0; + +done: + reftable_writer_free(wr); + if (tab_fd > 0) { + close(tab_fd); + tab_fd = 0; + } + if (err != 0 && temp_tab->len > 0) { + unlink(temp_tab->buf); + strbuf_release(temp_tab); + } + strbuf_release(&next_name); + return err; +} + +int stack_write_compact(struct reftable_stack *st, struct reftable_writer *wr, + int first, int last, + struct reftable_log_expiry_config *config) +{ + int subtabs_len = last - first + 1; + struct reftable_reader **subtabs = reftable_calloc( + sizeof(struct reftable_reader *) * (last - first + 1)); + struct reftable_merged_table *mt = NULL; + int err = 0; + struct reftable_iterator it = { 0 }; + struct reftable_ref_record ref = { 0 }; + struct reftable_log_record log = { 0 }; + + uint64_t entries = 0; + + int i = 0, j = 0; + for (i = first, j = 0; i <= last; i++) { + struct reftable_reader *t = st->merged->stack[i]; + subtabs[j++] = t; + st->stats.bytes += t->size; + } + reftable_writer_set_limits(wr, + st->merged->stack[first]->min_update_index, + st->merged->stack[last]->max_update_index); + + err = reftable_new_merged_table(&mt, subtabs, subtabs_len, + st->config.hash_id); + if (err < 0) { + reftable_free(subtabs); + goto done; + } + + err = reftable_merged_table_seek_ref(mt, &it, ""); + if (err < 0) + goto done; + + while (true) { + err = reftable_iterator_next_ref(&it, &ref); + if (err > 0) { + err = 0; + break; + } + if (err < 0) { + break; + } + if (first == 0 && reftable_ref_record_is_deletion(&ref)) { + continue; + } + + err = reftable_writer_add_ref(wr, &ref); + if (err < 0) { + break; + } + entries++; + } + reftable_iterator_destroy(&it); + + err = reftable_merged_table_seek_log(mt, &it, ""); + if (err < 0) + goto done; + + while (true) { + err = reftable_iterator_next_log(&it, &log); + if (err > 0) { + err = 0; + break; + } + if (err < 0) { + break; + } + if (first == 0 && reftable_log_record_is_deletion(&log)) { + continue; + } + + if (config != NULL && config->time > 0 && + log.time < config->time) { + continue; + } + + if (config != NULL && config->min_update_index > 0 && + log.update_index < config->min_update_index) { + continue; + } + + err = reftable_writer_add_log(wr, &log); + if (err < 0) { + break; + } + entries++; + } + +done: + reftable_iterator_destroy(&it); + if (mt != NULL) { + merged_table_clear(mt); + reftable_merged_table_free(mt); + } + reftable_ref_record_clear(&ref); + reftable_log_record_clear(&log); + st->stats.entries_written += entries; + return err; +} + +/* < 0: error. 0 == OK, > 0 attempt failed; could retry. */ +static int stack_compact_range(struct reftable_stack *st, int first, int last, + struct reftable_log_expiry_config *expiry) +{ + struct strbuf temp_tab_file_name = STRBUF_INIT; + struct strbuf new_table_name = STRBUF_INIT; + struct strbuf lock_file_name = STRBUF_INIT; + struct strbuf ref_list_contents = STRBUF_INIT; + struct strbuf new_table_path = STRBUF_INIT; + int err = 0; + bool have_lock = false; + int lock_file_fd = 0; + int compact_count = last - first + 1; + char **listp = NULL; + char **delete_on_success = + reftable_calloc(sizeof(char *) * (compact_count + 1)); + char **subtable_locks = + reftable_calloc(sizeof(char *) * (compact_count + 1)); + int i = 0; + int j = 0; + bool is_empty_table = false; + + if (first > last || (expiry == NULL && first == last)) { + err = 0; + goto done; + } + + st->stats.attempts++; + + strbuf_reset(&lock_file_name); + strbuf_addstr(&lock_file_name, st->list_file); + strbuf_addstr(&lock_file_name, ".lock"); + + lock_file_fd = + open(lock_file_name.buf, O_EXCL | O_CREAT | O_WRONLY, 0644); + if (lock_file_fd < 0) { + if (errno == EEXIST) { + err = 1; + } else { + err = REFTABLE_IO_ERROR; + } + goto done; + } + /* Don't want to write to the lock for now. */ + close(lock_file_fd); + lock_file_fd = 0; + + have_lock = true; + err = stack_uptodate(st); + if (err != 0) + goto done; + + for (i = first, j = 0; i <= last; i++) { + struct strbuf subtab_file_name = STRBUF_INIT; + struct strbuf subtab_lock = STRBUF_INIT; + int sublock_file_fd = -1; + + strbuf_addstr(&subtab_file_name, st->reftable_dir); + strbuf_addstr(&subtab_file_name, "/"); + strbuf_addstr(&subtab_file_name, + reader_name(st->merged->stack[i])); + + strbuf_reset(&subtab_lock); + strbuf_addbuf(&subtab_lock, &subtab_file_name); + strbuf_addstr(&subtab_lock, ".lock"); + + sublock_file_fd = open(subtab_lock.buf, + O_EXCL | O_CREAT | O_WRONLY, 0644); + if (sublock_file_fd > 0) { + close(sublock_file_fd); + } else if (sublock_file_fd < 0) { + if (errno == EEXIST) { + err = 1; + } else { + err = REFTABLE_IO_ERROR; + } + } + + subtable_locks[j] = subtab_lock.buf; + delete_on_success[j] = subtab_file_name.buf; + j++; + + if (err != 0) + goto done; + } + + err = unlink(lock_file_name.buf); + if (err < 0) + goto done; + have_lock = false; + + err = stack_compact_locked(st, first, last, &temp_tab_file_name, + expiry); + /* Compaction + tombstones can create an empty table out of non-empty + * tables. */ + is_empty_table = (err == REFTABLE_EMPTY_TABLE_ERROR); + if (is_empty_table) { + err = 0; + } + if (err < 0) + goto done; + + lock_file_fd = + open(lock_file_name.buf, O_EXCL | O_CREAT | O_WRONLY, 0644); + if (lock_file_fd < 0) { + if (errno == EEXIST) { + err = 1; + } else { + err = REFTABLE_IO_ERROR; + } + goto done; + } + have_lock = true; + + format_name(&new_table_name, st->merged->stack[first]->min_update_index, + st->merged->stack[last]->max_update_index); + strbuf_addstr(&new_table_name, ".ref"); + + strbuf_reset(&new_table_path); + strbuf_addstr(&new_table_path, st->reftable_dir); + strbuf_addstr(&new_table_path, "/"); + strbuf_addbuf(&new_table_path, &new_table_name); + + if (!is_empty_table) { + err = rename(temp_tab_file_name.buf, new_table_path.buf); + if (err < 0) { + err = REFTABLE_IO_ERROR; + goto done; + } + } + + for (i = 0; i < first; i++) { + strbuf_addstr(&ref_list_contents, st->merged->stack[i]->name); + strbuf_addstr(&ref_list_contents, "\n"); + } + if (!is_empty_table) { + strbuf_addbuf(&ref_list_contents, &new_table_name); + strbuf_addstr(&ref_list_contents, "\n"); + } + for (i = last + 1; i < st->merged->stack_len; i++) { + strbuf_addstr(&ref_list_contents, st->merged->stack[i]->name); + strbuf_addstr(&ref_list_contents, "\n"); + } + + err = write(lock_file_fd, ref_list_contents.buf, ref_list_contents.len); + if (err < 0) { + err = REFTABLE_IO_ERROR; + unlink(new_table_path.buf); + goto done; + } + err = close(lock_file_fd); + lock_file_fd = 0; + if (err < 0) { + err = REFTABLE_IO_ERROR; + unlink(new_table_path.buf); + goto done; + } + + err = rename(lock_file_name.buf, st->list_file); + if (err < 0) { + err = REFTABLE_IO_ERROR; + unlink(new_table_path.buf); + goto done; + } + have_lock = false; + + /* Reload the stack before deleting. On windows, we can only delete the + files after we closed them. + */ + err = reftable_stack_reload_maybe_reuse(st, first < last); + + listp = delete_on_success; + while (*listp) { + if (strcmp(*listp, new_table_path.buf)) { + unlink(*listp); + } + listp++; + } + +done: + free_names(delete_on_success); + + listp = subtable_locks; + while (*listp) { + unlink(*listp); + listp++; + } + free_names(subtable_locks); + if (lock_file_fd > 0) { + close(lock_file_fd); + lock_file_fd = 0; + } + if (have_lock) { + unlink(lock_file_name.buf); + } + strbuf_release(&new_table_name); + strbuf_release(&new_table_path); + strbuf_release(&ref_list_contents); + strbuf_release(&temp_tab_file_name); + strbuf_release(&lock_file_name); + return err; +} + +int reftable_stack_compact_all(struct reftable_stack *st, + struct reftable_log_expiry_config *config) +{ + return stack_compact_range(st, 0, st->merged->stack_len - 1, config); +} + +static int stack_compact_range_stats(struct reftable_stack *st, int first, + int last, + struct reftable_log_expiry_config *config) +{ + int err = stack_compact_range(st, first, last, config); + if (err > 0) { + st->stats.failures++; + } + return err; +} + +static int segment_size(struct segment *s) +{ + return s->end - s->start; +} + +int fastlog2(uint64_t sz) +{ + int l = 0; + if (sz == 0) + return 0; + for (; sz; sz /= 2) { + l++; + } + return l - 1; +} + +struct segment *sizes_to_segments(int *seglen, uint64_t *sizes, int n) +{ + struct segment *segs = reftable_calloc(sizeof(struct segment) * n); + int next = 0; + struct segment cur = { 0 }; + int i = 0; + + if (n == 0) { + *seglen = 0; + return segs; + } + for (i = 0; i < n; i++) { + int log = fastlog2(sizes[i]); + if (cur.log != log && cur.bytes > 0) { + struct segment fresh = { + .start = i, + }; + + segs[next++] = cur; + cur = fresh; + } + + cur.log = log; + cur.end = i + 1; + cur.bytes += sizes[i]; + } + segs[next++] = cur; + *seglen = next; + return segs; +} + +struct segment suggest_compaction_segment(uint64_t *sizes, int n) +{ + int seglen = 0; + struct segment *segs = sizes_to_segments(&seglen, sizes, n); + struct segment min_seg = { + .log = 64, + }; + int i = 0; + for (i = 0; i < seglen; i++) { + if (segment_size(&segs[i]) == 1) { + continue; + } + + if (segs[i].log < min_seg.log) { + min_seg = segs[i]; + } + } + + while (min_seg.start > 0) { + int prev = min_seg.start - 1; + if (fastlog2(min_seg.bytes) < fastlog2(sizes[prev])) { + break; + } + + min_seg.start = prev; + min_seg.bytes += sizes[prev]; + } + + reftable_free(segs); + return min_seg; +} + +static uint64_t *stack_table_sizes_for_compaction(struct reftable_stack *st) +{ + uint64_t *sizes = + reftable_calloc(sizeof(uint64_t) * st->merged->stack_len); + int version = (st->config.hash_id == SHA1_ID) ? 1 : 2; + int overhead = header_size(version) - 1; + int i = 0; + for (i = 0; i < st->merged->stack_len; i++) { + sizes[i] = st->merged->stack[i]->size - overhead; + } + return sizes; +} + +int reftable_stack_auto_compact(struct reftable_stack *st) +{ + uint64_t *sizes = stack_table_sizes_for_compaction(st); + struct segment seg = + suggest_compaction_segment(sizes, st->merged->stack_len); + reftable_free(sizes); + if (segment_size(&seg) > 0) + return stack_compact_range_stats(st, seg.start, seg.end - 1, + NULL); + + return 0; +} + +struct reftable_compaction_stats * +reftable_stack_compaction_stats(struct reftable_stack *st) +{ + return &st->stats; +} + +int reftable_stack_read_ref(struct reftable_stack *st, const char *refname, + struct reftable_ref_record *ref) +{ + struct reftable_table tab = { NULL }; + reftable_table_from_merged_table(&tab, reftable_stack_merged_table(st)); + return reftable_table_read_ref(&tab, refname, ref); +} + +int reftable_stack_read_log(struct reftable_stack *st, const char *refname, + struct reftable_log_record *log) +{ + struct reftable_iterator it = { 0 }; + struct reftable_merged_table *mt = reftable_stack_merged_table(st); + int err = reftable_merged_table_seek_log(mt, &it, refname); + if (err) + goto done; + + err = reftable_iterator_next_log(&it, log); + if (err) + goto done; + + if (strcmp(log->ref_name, refname) || + reftable_log_record_is_deletion(log)) { + err = 1; + goto done; + } + +done: + if (err) { + reftable_log_record_clear(log); + } + reftable_iterator_destroy(&it); + return err; +} + +int stack_check_addition(struct reftable_stack *st, const char *new_tab_name) +{ + int err = 0; + struct reftable_block_source src = { 0 }; + struct reftable_reader *rd = NULL; + struct reftable_table tab = { NULL }; + struct reftable_ref_record *refs = NULL; + struct reftable_iterator it = { NULL }; + int cap = 0; + int len = 0; + int i = 0; + + if (st->config.skip_name_check) + return 0; + + err = reftable_block_source_from_file(&src, new_tab_name); + if (err < 0) + goto done; + + err = reftable_new_reader(&rd, &src, new_tab_name); + if (err < 0) + goto done; + + err = reftable_reader_seek_ref(rd, &it, ""); + if (err > 0) { + err = 0; + goto done; + } + if (err < 0) + goto done; + + while (true) { + struct reftable_ref_record ref = { 0 }; + err = reftable_iterator_next_ref(&it, &ref); + if (err > 0) { + break; + } + if (err < 0) + goto done; + + if (len >= cap) { + cap = 2 * cap + 1; + refs = reftable_realloc(refs, cap * sizeof(refs[0])); + } + + refs[len++] = ref; + } + + reftable_table_from_merged_table(&tab, reftable_stack_merged_table(st)); + + err = validate_ref_record_addition(tab, refs, len); + +done: + for (i = 0; i < len; i++) { + reftable_ref_record_clear(&refs[i]); + } + + free(refs); + reftable_iterator_destroy(&it); + reftable_reader_free(rd); + return err; +} diff --git a/reftable/stack.h b/reftable/stack.h new file mode 100644 index 00000000000..60bca3b3e58 --- /dev/null +++ b/reftable/stack.h @@ -0,0 +1,48 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef STACK_H +#define STACK_H + +#include "reftable.h" +#include "system.h" + +struct reftable_stack { + char *list_file; + char *reftable_dir; + bool disable_auto_compact; + + struct reftable_write_options config; + + struct reftable_merged_table *merged; + struct reftable_compaction_stats stats; +}; + +int read_lines(const char *filename, char ***lines); +int stack_try_add(struct reftable_stack *st, + int (*write_table)(struct reftable_writer *wr, void *arg), + void *arg); +int stack_write_compact(struct reftable_stack *st, struct reftable_writer *wr, + int first, int last, + struct reftable_log_expiry_config *config); +int fastlog2(uint64_t sz); +int stack_check_addition(struct reftable_stack *st, const char *new_tab_name); +void reftable_addition_close(struct reftable_addition *add); +int reftable_stack_reload_maybe_reuse(struct reftable_stack *st, + bool reuse_open); + +struct segment { + int start, end; + int log; + uint64_t bytes; +}; + +struct segment *sizes_to_segments(int *seglen, uint64_t *sizes, int n); +struct segment suggest_compaction_segment(uint64_t *sizes, int n); + +#endif diff --git a/reftable/stack_test.c b/reftable/stack_test.c new file mode 100644 index 00000000000..9e3ebf939be --- /dev/null +++ b/reftable/stack_test.c @@ -0,0 +1,787 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "stack.h" + +#include "system.h" + +#include "merged.h" +#include "basics.h" +#include "constants.h" +#include "record.h" +#include "reftable.h" +#include "test_framework.h" +#include "reftable-tests.h" + +#include <sys/types.h> +#include <dirent.h> + +static void test_read_file(void) +{ + char fn[256] = "/tmp/stack.test_read_file.XXXXXX"; + int fd = mkstemp(fn); + char out[1024] = "line1\n\nline2\nline3"; + int n, err; + char **names = NULL; + char *want[] = { "line1", "line2", "line3" }; + int i = 0; + + assert(fd > 0); + n = write(fd, out, strlen(out)); + assert(n == strlen(out)); + err = close(fd); + assert(err >= 0); + + err = read_lines(fn, &names); + assert_err(err); + + for (i = 0; names[i] != NULL; i++) { + assert(0 == strcmp(want[i], names[i])); + } + free_names(names); + remove(fn); +} + +static void test_parse_names(void) +{ + char buf[] = "line\n"; + char **names = NULL; + parse_names(buf, strlen(buf), &names); + + assert(NULL != names[0]); + assert(0 == strcmp(names[0], "line")); + assert(NULL == names[1]); + free_names(names); +} + +static void test_names_equal(void) +{ + char *a[] = { "a", "b", "c", NULL }; + char *b[] = { "a", "b", "d", NULL }; + char *c[] = { "a", "b", NULL }; + + assert(names_equal(a, a)); + assert(!names_equal(a, b)); + assert(!names_equal(a, c)); +} + +static int write_test_ref(struct reftable_writer *wr, void *arg) +{ + struct reftable_ref_record *ref = arg; + reftable_writer_set_limits(wr, ref->update_index, ref->update_index); + return reftable_writer_add_ref(wr, ref); +} + +struct write_log_arg { + struct reftable_log_record *log; + uint64_t update_index; +}; + +static int write_test_log(struct reftable_writer *wr, void *arg) +{ + struct write_log_arg *wla = arg; + + reftable_writer_set_limits(wr, wla->update_index, wla->update_index); + return reftable_writer_add_log(wr, wla->log); +} + +static void test_reftable_stack_add_one(void) +{ + char dir[256] = "/tmp/stack_test.XXXXXX"; + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + int err; + struct reftable_ref_record ref = { + .ref_name = "HEAD", + .update_index = 1, + .target = "master", + }; + struct reftable_ref_record dest = { 0 }; + + assert(mkdtemp(dir)); + + err = reftable_new_stack(&st, dir, cfg); + assert_err(err); + + err = reftable_stack_add(st, &write_test_ref, &ref); + assert_err(err); + + err = reftable_stack_read_ref(st, ref.ref_name, &dest); + assert_err(err); + assert(0 == strcmp("master", dest.target)); + + reftable_ref_record_clear(&dest); + reftable_stack_destroy(st); + reftable_clear_dir(dir); +} + +static void test_reftable_stack_uptodate(void) +{ + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st1 = NULL; + struct reftable_stack *st2 = NULL; + char dir[256] = "/tmp/stack_test.XXXXXX"; + int err; + struct reftable_ref_record ref1 = { + .ref_name = "HEAD", + .update_index = 1, + .target = "master", + }; + struct reftable_ref_record ref2 = { + .ref_name = "branch2", + .update_index = 2, + .target = "master", + }; + + assert(mkdtemp(dir)); + + err = reftable_new_stack(&st1, dir, cfg); + assert_err(err); + + err = reftable_new_stack(&st2, dir, cfg); + assert_err(err); + + err = reftable_stack_add(st1, &write_test_ref, &ref1); + assert_err(err); + + err = reftable_stack_add(st2, &write_test_ref, &ref2); + assert(err == REFTABLE_LOCK_ERROR); + + err = reftable_stack_reload(st2); + assert_err(err); + + err = reftable_stack_add(st2, &write_test_ref, &ref2); + assert_err(err); + reftable_stack_destroy(st1); + reftable_stack_destroy(st2); + reftable_clear_dir(dir); +} + +static void test_reftable_stack_transaction_api(void) +{ + char dir[256] = "/tmp/stack_test.XXXXXX"; + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + int err; + struct reftable_addition *add = NULL; + + struct reftable_ref_record ref = { + .ref_name = "HEAD", + .update_index = 1, + .target = "master", + }; + struct reftable_ref_record dest = { 0 }; + + assert(mkdtemp(dir)); + + err = reftable_new_stack(&st, dir, cfg); + assert_err(err); + + reftable_addition_destroy(add); + + err = reftable_stack_new_addition(&add, st); + assert_err(err); + + err = reftable_addition_add(add, &write_test_ref, &ref); + assert_err(err); + + err = reftable_addition_commit(add); + assert_err(err); + + reftable_addition_destroy(add); + + err = reftable_stack_read_ref(st, ref.ref_name, &dest); + assert_err(err); + assert(0 == strcmp("master", dest.target)); + + reftable_ref_record_clear(&dest); + reftable_stack_destroy(st); + reftable_clear_dir(dir); +} + +static void test_reftable_stack_validate_refname(void) +{ + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + int err; + char dir[256] = "/tmp/stack_test.XXXXXX"; + int i; + struct reftable_ref_record ref = { + .ref_name = "a/b", + .update_index = 1, + .target = "master", + }; + char *additions[] = { "a", "a/b/c" }; + + assert(mkdtemp(dir)); + err = reftable_new_stack(&st, dir, cfg); + assert_err(err); + + err = reftable_stack_add(st, &write_test_ref, &ref); + assert_err(err); + + for (i = 0; i < ARRAY_SIZE(additions); i++) { + struct reftable_ref_record ref = { + .ref_name = additions[i], + .update_index = 1, + .target = "master", + }; + + err = reftable_stack_add(st, &write_test_ref, &ref); + assert(err == REFTABLE_NAME_CONFLICT); + } + + reftable_stack_destroy(st); + reftable_clear_dir(dir); +} + +static int write_error(struct reftable_writer *wr, void *arg) +{ + return *((int *)arg); +} + +static void test_reftable_stack_update_index_check(void) +{ + char dir[256] = "/tmp/stack_test.XXXXXX"; + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + int err; + struct reftable_ref_record ref1 = { + .ref_name = "name1", + .update_index = 1, + .target = "master", + }; + struct reftable_ref_record ref2 = { + .ref_name = "name2", + .update_index = 1, + .target = "master", + }; + assert(mkdtemp(dir)); + + err = reftable_new_stack(&st, dir, cfg); + assert_err(err); + + err = reftable_stack_add(st, &write_test_ref, &ref1); + assert_err(err); + + err = reftable_stack_add(st, &write_test_ref, &ref2); + assert(err == REFTABLE_API_ERROR); + reftable_stack_destroy(st); + reftable_clear_dir(dir); +} + +static void test_reftable_stack_lock_failure(void) +{ + char dir[256] = "/tmp/stack_test.XXXXXX"; + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + int err, i; + assert(mkdtemp(dir)); + + err = reftable_new_stack(&st, dir, cfg); + assert_err(err); + for (i = -1; i != REFTABLE_EMPTY_TABLE_ERROR; i--) { + err = reftable_stack_add(st, &write_error, &i); + assert(err == i); + } + + reftable_stack_destroy(st); + reftable_clear_dir(dir); +} + +static void test_reftable_stack_add(void) +{ + int i = 0; + int err = 0; + struct reftable_write_options cfg = { + .exact_log_message = true, + }; + struct reftable_stack *st = NULL; + char dir[256] = "/tmp/stack_test.XXXXXX"; + struct reftable_ref_record refs[2] = { { 0 } }; + struct reftable_log_record logs[2] = { { 0 } }; + int N = ARRAY_SIZE(refs); + + assert(mkdtemp(dir)); + + err = reftable_new_stack(&st, dir, cfg); + assert_err(err); + st->disable_auto_compact = true; + + for (i = 0; i < N; i++) { + char buf[256]; + snprintf(buf, sizeof(buf), "branch%02d", i); + refs[i].ref_name = xstrdup(buf); + refs[i].value = reftable_malloc(SHA1_SIZE); + refs[i].update_index = i + 1; + set_test_hash(refs[i].value, i); + + logs[i].ref_name = xstrdup(buf); + logs[i].update_index = N + i + 1; + logs[i].new_hash = reftable_malloc(SHA1_SIZE); + logs[i].email = xstrdup("identity@invalid"); + set_test_hash(logs[i].new_hash, i); + } + + for (i = 0; i < N; i++) { + int err = reftable_stack_add(st, &write_test_ref, &refs[i]); + assert_err(err); + } + + for (i = 0; i < N; i++) { + struct write_log_arg arg = { + .log = &logs[i], + .update_index = reftable_stack_next_update_index(st), + }; + int err = reftable_stack_add(st, &write_test_log, &arg); + assert_err(err); + } + + err = reftable_stack_compact_all(st, NULL); + assert_err(err); + + for (i = 0; i < N; i++) { + struct reftable_ref_record dest = { 0 }; + int err = reftable_stack_read_ref(st, refs[i].ref_name, &dest); + assert_err(err); + assert(reftable_ref_record_equal(&dest, refs + i, SHA1_SIZE)); + reftable_ref_record_clear(&dest); + } + + for (i = 0; i < N; i++) { + struct reftable_log_record dest = { 0 }; + int err = reftable_stack_read_log(st, refs[i].ref_name, &dest); + assert_err(err); + assert(reftable_log_record_equal(&dest, logs + i, SHA1_SIZE)); + reftable_log_record_clear(&dest); + } + + /* cleanup */ + reftable_stack_destroy(st); + for (i = 0; i < N; i++) { + reftable_ref_record_clear(&refs[i]); + reftable_log_record_clear(&logs[i]); + } + reftable_clear_dir(dir); +} + +static void test_reftable_stack_log_normalize(void) +{ + int err = 0; + struct reftable_write_options cfg = { + 0, + }; + struct reftable_stack *st = NULL; + char dir[256] = "/tmp/stack_test.XXXXXX"; + + uint8_t h1[SHA1_SIZE] = { 0x01 }, h2[SHA1_SIZE] = { 0x02 }; + + struct reftable_log_record input = { + .ref_name = "branch", + .update_index = 1, + .new_hash = h1, + .old_hash = h2, + }; + struct reftable_log_record dest = { + .update_index = 0, + }; + struct write_log_arg arg = { + .log = &input, + .update_index = 1, + }; + + assert(mkdtemp(dir)); + err = reftable_new_stack(&st, dir, cfg); + assert_err(err); + + input.message = "one\ntwo"; + err = reftable_stack_add(st, &write_test_log, &arg); + assert(err == REFTABLE_API_ERROR); + + input.message = "one"; + err = reftable_stack_add(st, &write_test_log, &arg); + assert_err(err); + + err = reftable_stack_read_log(st, input.ref_name, &dest); + assert_err(err); + assert(0 == strcmp(dest.message, "one\n")); + + input.message = "two\n"; + arg.update_index = 2; + err = reftable_stack_add(st, &write_test_log, &arg); + assert_err(err); + err = reftable_stack_read_log(st, input.ref_name, &dest); + assert_err(err); + assert(0 == strcmp(dest.message, "two\n")); + + /* cleanup */ + reftable_stack_destroy(st); + reftable_log_record_clear(&dest); + reftable_clear_dir(dir); +} + +static void test_reftable_stack_tombstone(void) +{ + int i = 0; + char dir[256] = "/tmp/stack_test.XXXXXX"; + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + int err; + struct reftable_ref_record refs[2] = { { 0 } }; + struct reftable_log_record logs[2] = { { 0 } }; + int N = ARRAY_SIZE(refs); + struct reftable_ref_record dest = { 0 }; + struct reftable_log_record log_dest = { 0 }; + + assert(mkdtemp(dir)); + + err = reftable_new_stack(&st, dir, cfg); + assert_err(err); + + for (i = 0; i < N; i++) { + const char *buf = "branch"; + refs[i].ref_name = xstrdup(buf); + refs[i].update_index = i + 1; + if (i % 2 == 0) { + refs[i].value = reftable_malloc(SHA1_SIZE); + set_test_hash(refs[i].value, i); + } + logs[i].ref_name = xstrdup(buf); + /* update_index is part of the key. */ + logs[i].update_index = 42; + if (i % 2 == 0) { + logs[i].new_hash = reftable_malloc(SHA1_SIZE); + set_test_hash(logs[i].new_hash, i); + logs[i].email = xstrdup("identity@invalid"); + } + } + for (i = 0; i < N; i++) { + int err = reftable_stack_add(st, &write_test_ref, &refs[i]); + assert_err(err); + } + for (i = 0; i < N; i++) { + struct write_log_arg arg = { + .log = &logs[i], + .update_index = reftable_stack_next_update_index(st), + }; + int err = reftable_stack_add(st, &write_test_log, &arg); + assert_err(err); + } + + err = reftable_stack_read_ref(st, "branch", &dest); + assert(err == 1); + reftable_ref_record_clear(&dest); + + err = reftable_stack_read_log(st, "branch", &log_dest); + assert(err == 1); + reftable_log_record_clear(&log_dest); + + err = reftable_stack_compact_all(st, NULL); + assert_err(err); + + err = reftable_stack_read_ref(st, "branch", &dest); + assert(err == 1); + + err = reftable_stack_read_log(st, "branch", &log_dest); + assert(err == 1); + reftable_ref_record_clear(&dest); + reftable_log_record_clear(&log_dest); + + /* cleanup */ + reftable_stack_destroy(st); + for (i = 0; i < N; i++) { + reftable_ref_record_clear(&refs[i]); + reftable_log_record_clear(&logs[i]); + } + reftable_clear_dir(dir); +} + +static void test_reftable_stack_hash_id(void) +{ + char dir[256] = "/tmp/stack_test.XXXXXX"; + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + int err; + + struct reftable_ref_record ref = { + .ref_name = "master", + .target = "target", + .update_index = 1, + }; + struct reftable_write_options cfg32 = { .hash_id = SHA256_ID }; + struct reftable_stack *st32 = NULL; + struct reftable_write_options cfg_default = { 0 }; + struct reftable_stack *st_default = NULL; + struct reftable_ref_record dest = { 0 }; + + assert(mkdtemp(dir)); + err = reftable_new_stack(&st, dir, cfg); + assert_err(err); + + err = reftable_stack_add(st, &write_test_ref, &ref); + assert_err(err); + + /* can't read it with the wrong hash ID. */ + err = reftable_new_stack(&st32, dir, cfg32); + assert(err == REFTABLE_FORMAT_ERROR); + + /* check that we can read it back with default config too. */ + err = reftable_new_stack(&st_default, dir, cfg_default); + assert_err(err); + + err = reftable_stack_read_ref(st_default, "master", &dest); + assert_err(err); + + assert(!strcmp(dest.target, ref.target)); + reftable_ref_record_clear(&dest); + reftable_stack_destroy(st); + reftable_stack_destroy(st_default); + reftable_clear_dir(dir); +} + +static void test_log2(void) +{ + assert(1 == fastlog2(3)); + assert(2 == fastlog2(4)); + assert(2 == fastlog2(5)); +} + +static void test_sizes_to_segments(void) +{ + uint64_t sizes[] = { 2, 3, 4, 5, 7, 9 }; + /* .................0 1 2 3 4 5 */ + + int seglen = 0; + struct segment *segs = + sizes_to_segments(&seglen, sizes, ARRAY_SIZE(sizes)); + assert(segs[2].log == 3); + assert(segs[2].start == 5); + assert(segs[2].end == 6); + + assert(segs[1].log == 2); + assert(segs[1].start == 2); + assert(segs[1].end == 5); + reftable_free(segs); +} + +static void test_sizes_to_segments_empty(void) +{ + uint64_t sizes[0]; + + int seglen = 0; + struct segment *segs = + sizes_to_segments(&seglen, sizes, ARRAY_SIZE(sizes)); + assert(seglen == 0); + reftable_free(segs); +} + +static void test_sizes_to_segments_all_equal(void) +{ + uint64_t sizes[] = { 5, 5 }; + + int seglen = 0; + struct segment *segs = + sizes_to_segments(&seglen, sizes, ARRAY_SIZE(sizes)); + assert(seglen == 1); + assert(segs[0].start == 0); + assert(segs[0].end == 2); + reftable_free(segs); +} + +static void test_suggest_compaction_segment(void) +{ + uint64_t sizes[] = { 128, 64, 17, 16, 9, 9, 9, 16, 16 }; + /* .................0 1 2 3 4 5 6 */ + struct segment min = + suggest_compaction_segment(sizes, ARRAY_SIZE(sizes)); + assert(min.start == 2); + assert(min.end == 7); +} + +static void test_suggest_compaction_segment_nothing(void) +{ + uint64_t sizes[] = { 64, 32, 16, 8, 4, 2 }; + struct segment result = + suggest_compaction_segment(sizes, ARRAY_SIZE(sizes)); + assert(result.start == result.end); +} + +static void test_reflog_expire(void) +{ + char dir[256] = "/tmp/stack.test_reflog_expire.XXXXXX"; + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + struct reftable_log_record logs[20] = { { 0 } }; + int N = ARRAY_SIZE(logs) - 1; + int i = 0; + int err; + struct reftable_log_expiry_config expiry = { + .time = 10, + }; + struct reftable_log_record log = { 0 }; + + assert(mkdtemp(dir)); + + err = reftable_new_stack(&st, dir, cfg); + assert_err(err); + + for (i = 1; i <= N; i++) { + char buf[256]; + snprintf(buf, sizeof(buf), "branch%02d", i); + + logs[i].ref_name = xstrdup(buf); + logs[i].update_index = i; + logs[i].time = i; + logs[i].new_hash = reftable_malloc(SHA1_SIZE); + logs[i].email = xstrdup("identity@invalid"); + set_test_hash(logs[i].new_hash, i); + } + + for (i = 1; i <= N; i++) { + struct write_log_arg arg = { + .log = &logs[i], + .update_index = reftable_stack_next_update_index(st), + }; + int err = reftable_stack_add(st, &write_test_log, &arg); + assert_err(err); + } + + err = reftable_stack_compact_all(st, NULL); + assert_err(err); + + err = reftable_stack_compact_all(st, &expiry); + assert_err(err); + + err = reftable_stack_read_log(st, logs[9].ref_name, &log); + assert(err == 1); + + err = reftable_stack_read_log(st, logs[11].ref_name, &log); + assert_err(err); + + expiry.min_update_index = 15; + err = reftable_stack_compact_all(st, &expiry); + assert_err(err); + + err = reftable_stack_read_log(st, logs[14].ref_name, &log); + assert(err == 1); + + err = reftable_stack_read_log(st, logs[16].ref_name, &log); + assert_err(err); + + /* cleanup */ + reftable_stack_destroy(st); + for (i = 0; i <= N; i++) { + reftable_log_record_clear(&logs[i]); + } + reftable_clear_dir(dir); + reftable_log_record_clear(&log); +} + +static int write_nothing(struct reftable_writer *wr, void *arg) +{ + reftable_writer_set_limits(wr, 1, 1); + return 0; +} + +static void test_empty_add(void) +{ + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + int err; + char dir[256] = "/tmp/stack_test.XXXXXX"; + struct reftable_stack *st2 = NULL; + + assert(mkdtemp(dir)); + + err = reftable_new_stack(&st, dir, cfg); + assert_err(err); + + err = reftable_stack_add(st, &write_nothing, NULL); + assert_err(err); + + err = reftable_new_stack(&st2, dir, cfg); + assert_err(err); + reftable_clear_dir(dir); + reftable_stack_destroy(st); + reftable_stack_destroy(st2); +} + +static void test_reftable_stack_auto_compaction(void) +{ + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + char dir[256] = "/tmp/stack_test.XXXXXX"; + int err, i; + int N = 100; + assert(mkdtemp(dir)); + + err = reftable_new_stack(&st, dir, cfg); + assert_err(err); + + for (i = 0; i < N; i++) { + char name[100]; + struct reftable_ref_record ref = { + .ref_name = name, + .update_index = reftable_stack_next_update_index(st), + .target = "master", + }; + snprintf(name, sizeof(name), "branch%04d", i); + + err = reftable_stack_add(st, &write_test_ref, &ref); + assert_err(err); + + assert(i < 3 || st->merged->stack_len < 2 * fastlog2(i)); + } + + assert(reftable_stack_compaction_stats(st)->entries_written < + (uint64_t)(N * fastlog2(N))); + + reftable_stack_destroy(st); + reftable_clear_dir(dir); +} + +int stack_test_main(int argc, const char *argv[]) +{ + add_test_case("test_reftable_stack_uptodate", + &test_reftable_stack_uptodate); + add_test_case("test_reftable_stack_transaction_api", + &test_reftable_stack_transaction_api); + add_test_case("test_reftable_stack_hash_id", + &test_reftable_stack_hash_id); + add_test_case("test_sizes_to_segments_all_equal", + &test_sizes_to_segments_all_equal); + add_test_case("test_reftable_stack_auto_compaction", + &test_reftable_stack_auto_compaction); + add_test_case("test_reftable_stack_validate_refname", + &test_reftable_stack_validate_refname); + add_test_case("test_reftable_stack_update_index_check", + &test_reftable_stack_update_index_check); + add_test_case("test_reftable_stack_lock_failure", + &test_reftable_stack_lock_failure); + add_test_case("test_reftable_stack_log_normalize", + &test_reftable_stack_log_normalize); + add_test_case("test_reftable_stack_tombstone", + &test_reftable_stack_tombstone); + add_test_case("test_reftable_stack_add_one", + &test_reftable_stack_add_one); + add_test_case("test_empty_add", test_empty_add); + add_test_case("test_reflog_expire", test_reflog_expire); + add_test_case("test_suggest_compaction_segment", + &test_suggest_compaction_segment); + add_test_case("test_suggest_compaction_segment_nothing", + &test_suggest_compaction_segment_nothing); + add_test_case("test_sizes_to_segments", &test_sizes_to_segments); + add_test_case("test_sizes_to_segments_empty", + &test_sizes_to_segments_empty); + add_test_case("test_log2", &test_log2); + add_test_case("test_parse_names", &test_parse_names); + add_test_case("test_read_file", &test_read_file); + add_test_case("test_names_equal", &test_names_equal); + add_test_case("test_reftable_stack_add", &test_reftable_stack_add); + return test_main(argc, argv); +} diff --git a/reftable/strbuf.c b/reftable/strbuf.c new file mode 100644 index 00000000000..eec446fb958 --- /dev/null +++ b/reftable/strbuf.c @@ -0,0 +1,206 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "strbuf.h" + +#include "system.h" +#include "reftable.h" +#include "basics.h" + +#ifdef REFTABLE_STANDALONE + +void strbuf_init(struct strbuf *s, size_t alloc) +{ + struct strbuf empty = STRBUF_INIT; + *s = empty; +} + +void strbuf_grow(struct strbuf *s, size_t extra) +{ + size_t newcap = s->len + extra + 1; + if (newcap > s->cap) { + s->buf = reftable_realloc(s->buf, newcap); + s->cap = newcap; + } +} + +static void strbuf_resize(struct strbuf *s, int l) +{ + int zl = l + 1; /* one uint8_t for 0 termination. */ + assert(s->canary == STRBUF_CANARY); + if (s->cap < zl) { + int c = s->cap * 2; + if (c < zl) { + c = zl; + } + s->cap = c; + s->buf = reftable_realloc(s->buf, s->cap); + } + s->len = l; + s->buf[l] = 0; +} + +void strbuf_setlen(struct strbuf *s, size_t l) +{ + assert(s->cap >= l + 1); + s->len = l; + s->buf[l] = 0; +} + +void strbuf_reset(struct strbuf *s) +{ + strbuf_resize(s, 0); +} + +void strbuf_addstr(struct strbuf *d, const char *s) +{ + int l1 = d->len; + int l2 = strlen(s); + assert(d->canary == STRBUF_CANARY); + + strbuf_resize(d, l2 + l1); + memcpy(d->buf + l1, s, l2); +} + +void strbuf_addbuf(struct strbuf *s, struct strbuf *a) +{ + int end = s->len; + assert(s->canary == STRBUF_CANARY); + strbuf_resize(s, s->len + a->len); + memcpy(s->buf + end, a->buf, a->len); +} + +char *strbuf_detach(struct strbuf *s, size_t *sz) +{ + char *p = NULL; + p = (char *)s->buf; + if (sz) + *sz = s->len; + s->buf = NULL; + s->cap = 0; + s->len = 0; + return p; +} + +void strbuf_release(struct strbuf *s) +{ + assert(s->canary == STRBUF_CANARY); + s->cap = 0; + s->len = 0; + reftable_free(s->buf); + s->buf = NULL; +} + +int strbuf_cmp(const struct strbuf *a, const struct strbuf *b) +{ + int min = a->len < b->len ? a->len : b->len; + int res = memcmp(a->buf, b->buf, min); + assert(a->canary == STRBUF_CANARY); + assert(b->canary == STRBUF_CANARY); + if (res != 0) + return res; + if (a->len < b->len) + return -1; + else if (a->len > b->len) + return 1; + else + return 0; +} + +int strbuf_add(struct strbuf *b, const void *data, size_t sz) +{ + assert(b->canary == STRBUF_CANARY); + strbuf_grow(b, sz); + memcpy(b->buf + b->len, data, sz); + b->len += sz; + b->buf[b->len] = 0; + return sz; +} + +#endif + +static uint64_t strbuf_size(void *b) +{ + return ((struct strbuf *)b)->len; +} + +int strbuf_add_void(void *b, const void *data, size_t sz) +{ + strbuf_add((struct strbuf *)b, data, sz); + return sz; +} + +static void strbuf_return_block(void *b, struct reftable_block *dest) +{ + memset(dest->data, 0xff, dest->len); + reftable_free(dest->data); +} + +static void strbuf_close(void *b) +{ +} + +static int strbuf_read_block(void *v, struct reftable_block *dest, uint64_t off, + uint32_t size) +{ + struct strbuf *b = (struct strbuf *)v; + assert(off + size <= b->len); + dest->data = reftable_calloc(size); + memcpy(dest->data, b->buf + off, size); + dest->len = size; + return size; +} + +struct reftable_block_source_vtable strbuf_vtable = { + .size = &strbuf_size, + .read_block = &strbuf_read_block, + .return_block = &strbuf_return_block, + .close = &strbuf_close, +}; + +void block_source_from_strbuf(struct reftable_block_source *bs, + struct strbuf *buf) +{ + assert(bs->ops == NULL); + bs->ops = &strbuf_vtable; + bs->arg = buf; +} + +static void malloc_return_block(void *b, struct reftable_block *dest) +{ + memset(dest->data, 0xff, dest->len); + reftable_free(dest->data); +} + +struct reftable_block_source_vtable malloc_vtable = { + .return_block = &malloc_return_block, +}; + +struct reftable_block_source malloc_block_source_instance = { + .ops = &malloc_vtable, +}; + +struct reftable_block_source malloc_block_source(void) +{ + return malloc_block_source_instance; +} + +int common_prefix_size(struct strbuf *a, struct strbuf *b) +{ + int p = 0; + while (p < a->len && p < b->len) { + if (a->buf[p] != b->buf[p]) { + break; + } + p++; + } + + return p; +} + +struct strbuf reftable_empty_strbuf = STRBUF_INIT; diff --git a/reftable/strbuf.h b/reftable/strbuf.h new file mode 100644 index 00000000000..c9a77b1fb55 --- /dev/null +++ b/reftable/strbuf.h @@ -0,0 +1,88 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef SLICE_H +#define SLICE_H + +#ifdef REFTABLE_STANDALONE + +#include "basics.h" +#include "reftable.h" + +/* + Provides a bounds-checked, growable byte ranges. To use, initialize as "strbuf + x = STRBUF_INIT;" + */ +struct strbuf { + int len; + int cap; + char *buf; + + /* Used to enforce initialization with STRBUF_INIT */ + uint8_t canary; +}; +#define STRBUF_CANARY 0x42 +#define STRBUF_INIT \ + { \ + 0, 0, NULL, STRBUF_CANARY \ + } + +void strbuf_addstr(struct strbuf *dest, const char *src); + +/* Deallocate and clear strbuf */ +void strbuf_release(struct strbuf *strbuf); + +/* Set strbuf to 0 length, but retain buffer. */ +void strbuf_reset(struct strbuf *strbuf); + +/* Initializes a strbuf. Accepts a strbuf with random garbage. */ +void strbuf_init(struct strbuf *strbuf, size_t alloc); + +/* Return `buf`, clearing out `s`. Optionally return len (not cap) in `sz`. */ +char *strbuf_detach(struct strbuf *s, size_t *sz); + +/* Set length of the slace to `l`, but don't reallocated. */ +void strbuf_setlen(struct strbuf *s, size_t l); + +/* Ensure `l` bytes beyond current length are available */ +void strbuf_grow(struct strbuf *s, size_t l); + +/* Signed comparison */ +int strbuf_cmp(const struct strbuf *a, const struct strbuf *b); + +/* Append `data` to the `dest` strbuf. */ +int strbuf_add(struct strbuf *dest, const void *data, size_t sz); + +/* Append `add` to `dest. */ +void strbuf_addbuf(struct strbuf *dest, struct strbuf *add); + +#else + +#include "../git-compat-util.h" +#include "../strbuf.h" + +#endif + +extern struct strbuf reftable_empty_strbuf; + +/* Like strbuf_add, but suitable for passing to reftable_new_writer + */ +int strbuf_add_void(void *b, const void *data, size_t sz); + +/* Find the longest shared prefix size of `a` and `b` */ +int common_prefix_size(struct strbuf *a, struct strbuf *b); + +struct reftable_block_source; + +/* Create an in-memory block source for reading reftables */ +void block_source_from_strbuf(struct reftable_block_source *bs, + struct strbuf *buf); + +struct reftable_block_source malloc_block_source(void); + +#endif diff --git a/reftable/strbuf_test.c b/reftable/strbuf_test.c new file mode 100644 index 00000000000..862ed867916 --- /dev/null +++ b/reftable/strbuf_test.c @@ -0,0 +1,39 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "strbuf.h" + +#include "system.h" + +#include "basics.h" +#include "record.h" +#include "reftable.h" +#include "test_framework.h" +#include "reftable-tests.h" + +static void test_strbuf(void) +{ + struct strbuf s = STRBUF_INIT; + struct strbuf t = STRBUF_INIT; + + strbuf_addstr(&s, "abc"); + assert(0 == strcmp("abc", s.buf)); + + strbuf_addstr(&t, "pqr"); + strbuf_addbuf(&s, &t); + assert(0 == strcmp("abcpqr", s.buf)); + + strbuf_release(&s); + strbuf_release(&t); +} + +int strbuf_test_main(int argc, const char *argv[]) +{ + add_test_case("test_strbuf", &test_strbuf); + return test_main(argc, argv); +} diff --git a/reftable/system.h b/reftable/system.h new file mode 100644 index 00000000000..6629b1104cf --- /dev/null +++ b/reftable/system.h @@ -0,0 +1,53 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef SYSTEM_H +#define SYSTEM_H + +#ifndef REFTABLE_STANDALONE + +#include "git-compat-util.h" +#include "cache.h" +#include <zlib.h> + +#else + +#include <assert.h> +#include <errno.h> +#include <fcntl.h> +#include <inttypes.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/stat.h> +#include <sys/time.h> +#include <sys/types.h> +#include <unistd.h> +#include <zlib.h> + +#include "compat.h" + +#endif /* REFTABLE_STANDALONE */ + +void reftable_clear_dir(const char *dirname); + +#define SHA1_ID 0x73686131 +#define SHA256_ID 0x73323536 +#define SHA1_SIZE 20 +#define SHA256_SIZE 32 + +typedef int bool; + +/* This is uncompress2, which is only available in zlib as of 2017. + */ +int uncompress_return_consumed(Bytef *dest, uLongf *destLen, + const Bytef *source, uLong *sourceLen); +int hash_size(uint32_t id); + +#endif diff --git a/reftable/test_framework.c b/reftable/test_framework.c new file mode 100644 index 00000000000..f97c2d6df8b --- /dev/null +++ b/reftable/test_framework.c @@ -0,0 +1,69 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "test_framework.h" + +#include "system.h" +#include "basics.h" +#include "constants.h" + +struct test_case **test_cases; +int test_case_len; +int test_case_cap; + +struct test_case *new_test_case(const char *name, void (*testfunc)(void)) +{ + struct test_case *tc = reftable_malloc(sizeof(struct test_case)); + tc->name = name; + tc->testfunc = testfunc; + return tc; +} + +struct test_case *add_test_case(const char *name, void (*testfunc)(void)) +{ + struct test_case *tc = new_test_case(name, testfunc); + if (test_case_len == test_case_cap) { + test_case_cap = 2 * test_case_cap + 1; + test_cases = reftable_realloc( + test_cases, sizeof(struct test_case) * test_case_cap); + } + + test_cases[test_case_len++] = tc; + return tc; +} + +int test_main(int argc, const char *argv[]) +{ + const char *filter = NULL; + int i = 0; + if (argc > 1) { + filter = argv[1]; + } + + for (i = 0; i < test_case_len; i++) { + const char *name = test_cases[i]->name; + if (filter == NULL || strstr(name, filter) != NULL) { + printf("case %s\n", name); + test_cases[i]->testfunc(); + } else { + printf("skip %s\n", name); + } + + reftable_free(test_cases[i]); + } + reftable_free(test_cases); + test_cases = 0; + test_case_len = 0; + test_case_cap = 0; + return 0; +} + +void set_test_hash(uint8_t *p, int i) +{ + memset(p, (uint8_t)i, hash_size(SHA1_ID)); +} diff --git a/reftable/test_framework.h b/reftable/test_framework.h new file mode 100644 index 00000000000..6a0009c1e54 --- /dev/null +++ b/reftable/test_framework.h @@ -0,0 +1,64 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef TEST_FRAMEWORK_H +#define TEST_FRAMEWORK_H + +#include "system.h" + +#include "reftable.h" + +#ifdef NDEBUG +#undef NDEBUG +#endif + +#include "system.h" + +#ifdef assert +#undef assert +#endif + +#define assert_err(c) \ + if (c != 0) { \ + fflush(stderr); \ + fflush(stdout); \ + fprintf(stderr, "%s: %d: error == %d (%s), want 0\n", \ + __FILE__, __LINE__, c, reftable_error_str(c)); \ + abort(); \ + } + +#define assert_streq(a, b) \ + if (strcmp(a, b)) { \ + fflush(stderr); \ + fflush(stdout); \ + fprintf(stderr, "%s:%d: %s (%s) != %s (%s)\n", __FILE__, \ + __LINE__, #a, a, #b, b); \ + abort(); \ + } + +#define assert(c) \ + if (!(c)) { \ + fflush(stderr); \ + fflush(stdout); \ + fprintf(stderr, "%s: %d: failed assertion %s\n", __FILE__, \ + __LINE__, #c); \ + abort(); \ + } + +struct test_case { + const char *name; + void (*testfunc)(void); +}; + +struct test_case *new_test_case(const char *name, void (*testfunc)(void)); +struct test_case *add_test_case(const char *name, void (*testfunc)(void)); +int test_main(int argc, const char *argv[]); + +void set_test_hash(uint8_t *p, int i); + +#endif diff --git a/reftable/tree.c b/reftable/tree.c new file mode 100644 index 00000000000..0061d14e306 --- /dev/null +++ b/reftable/tree.c @@ -0,0 +1,63 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "tree.h" + +#include "basics.h" +#include "system.h" + +struct tree_node *tree_search(void *key, struct tree_node **rootp, + int (*compare)(const void *, const void *), + int insert) +{ + int res; + if (*rootp == NULL) { + if (!insert) { + return NULL; + } else { + struct tree_node *n = + reftable_calloc(sizeof(struct tree_node)); + n->key = key; + *rootp = n; + return *rootp; + } + } + + res = compare(key, (*rootp)->key); + if (res < 0) + return tree_search(key, &(*rootp)->left, compare, insert); + else if (res > 0) + return tree_search(key, &(*rootp)->right, compare, insert); + return *rootp; +} + +void infix_walk(struct tree_node *t, void (*action)(void *arg, void *key), + void *arg) +{ + if (t->left != NULL) { + infix_walk(t->left, action, arg); + } + action(arg, t->key); + if (t->right != NULL) { + infix_walk(t->right, action, arg); + } +} + +void tree_free(struct tree_node *t) +{ + if (t == NULL) { + return; + } + if (t->left != NULL) { + tree_free(t->left); + } + if (t->right != NULL) { + tree_free(t->right); + } + reftable_free(t); +} diff --git a/reftable/tree.h b/reftable/tree.h new file mode 100644 index 00000000000..954512e9a3a --- /dev/null +++ b/reftable/tree.h @@ -0,0 +1,34 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef TREE_H +#define TREE_H + +/* tree_node is a generic binary search tree. */ +struct tree_node { + void *key; + struct tree_node *left, *right; +}; + +/* looks for `key` in `rootp` using `compare` as comparison function. If insert + is set, insert the key if it's not found. Else, return NULL. +*/ +struct tree_node *tree_search(void *key, struct tree_node **rootp, + int (*compare)(const void *, const void *), + int insert); + +/* performs an infix walk of the tree. */ +void infix_walk(struct tree_node *t, void (*action)(void *arg, void *key), + void *arg); + +/* + deallocates the tree nodes recursively. Keys should be deallocated separately + by walking over the tree. */ +void tree_free(struct tree_node *t); + +#endif diff --git a/reftable/tree_test.c b/reftable/tree_test.c new file mode 100644 index 00000000000..c6d448cbe8a --- /dev/null +++ b/reftable/tree_test.c @@ -0,0 +1,62 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "tree.h" + +#include "basics.h" +#include "record.h" +#include "reftable.h" +#include "test_framework.h" +#include "reftable-tests.h" + +static int test_compare(const void *a, const void *b) +{ + return (char *)a - (char *)b; +} + +struct curry { + void *last; +}; + +static void check_increasing(void *arg, void *key) +{ + struct curry *c = (struct curry *)arg; + if (c->last != NULL) { + assert(test_compare(c->last, key) < 0); + } + c->last = key; +} + +static void test_tree(void) +{ + struct tree_node *root = NULL; + + void *values[11] = { 0 }; + struct tree_node *nodes[11] = { 0 }; + int i = 1; + struct curry c = { 0 }; + do { + nodes[i] = tree_search(values + i, &root, &test_compare, 1); + i = (i * 7) % 11; + } while (i != 1); + + for (i = 1; i < ARRAY_SIZE(nodes); i++) { + assert(values + i == nodes[i]->key); + assert(nodes[i] == + tree_search(values + i, &root, &test_compare, 0)); + } + + infix_walk(root, check_increasing, &c); + tree_free(root); +} + +int tree_test_main(int argc, const char *argv[]) +{ + add_test_case("test_tree", &test_tree); + return test_main(argc, argv); +} diff --git a/reftable/update.sh b/reftable/update.sh new file mode 100755 index 00000000000..4dadd875f4a --- /dev/null +++ b/reftable/update.sh @@ -0,0 +1,22 @@ +#!/bin/sh + +set -eu + +# Override this to import from somewhere else, say "../reftable". +SRC=${SRC:-origin} +BRANCH=${BRANCH:-master} + +((git --git-dir reftable-repo/.git fetch -f ${SRC} ${BRANCH}:import && cd reftable-repo && git checkout -f $(git rev-parse import) ) || + git clone https://github.com/google/reftable reftable-repo) + +cp reftable-repo/c/*.[ch] reftable/ +cp reftable-repo/c/include/*.[ch] reftable/ +cp reftable-repo/LICENSE reftable/ + +git --git-dir reftable-repo/.git show --no-patch --format=oneline HEAD \ + > reftable/VERSION + +mv reftable/system.h reftable/system.h~ +sed 's|if REFTABLE_IN_GITCORE|if 1 /* REFTABLE_IN_GITCORE */|' < reftable/system.h~ > reftable/system.h + +git add reftable/*.[ch] reftable/LICENSE reftable/VERSION diff --git a/reftable/writer.c b/reftable/writer.c new file mode 100644 index 00000000000..670009fac62 --- /dev/null +++ b/reftable/writer.c @@ -0,0 +1,662 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#include "writer.h" + +#include "system.h" + +#include "block.h" +#include "constants.h" +#include "record.h" +#include "reftable.h" +#include "tree.h" + +static struct reftable_block_stats * +writer_reftable_block_stats(struct reftable_writer *w, uint8_t typ) +{ + switch (typ) { + case 'r': + return &w->stats.ref_stats; + case 'o': + return &w->stats.obj_stats; + case 'i': + return &w->stats.idx_stats; + case 'g': + return &w->stats.log_stats; + } + assert(false); + return NULL; +} + +/* write data, queuing the padding for the next write. Returns negative for + * error. */ +static int padded_write(struct reftable_writer *w, uint8_t *data, size_t len, + int padding) +{ + int n = 0; + if (w->pending_padding > 0) { + uint8_t *zeroed = reftable_calloc(w->pending_padding); + int n = w->write(w->write_arg, zeroed, w->pending_padding); + if (n < 0) + return n; + + w->pending_padding = 0; + reftable_free(zeroed); + } + + w->pending_padding = padding; + n = w->write(w->write_arg, data, len); + if (n < 0) + return n; + n += padding; + return 0; +} + +static void options_set_defaults(struct reftable_write_options *opts) +{ + if (opts->restart_interval == 0) { + opts->restart_interval = 16; + } + + if (opts->hash_id == 0) { + opts->hash_id = SHA1_ID; + } + if (opts->block_size == 0) { + opts->block_size = DEFAULT_BLOCK_SIZE; + } +} + +static int writer_version(struct reftable_writer *w) +{ + return (w->opts.hash_id == 0 || w->opts.hash_id == SHA1_ID) ? 1 : 2; +} + +static int writer_write_header(struct reftable_writer *w, uint8_t *dest) +{ + memcpy((char *)dest, "REFT", 4); + + dest[4] = writer_version(w); + + put_be24(dest + 5, w->opts.block_size); + put_be64(dest + 8, w->min_update_index); + put_be64(dest + 16, w->max_update_index); + if (writer_version(w) == 2) { + put_be32(dest + 24, w->opts.hash_id); + } + return header_size(writer_version(w)); +} + +static void writer_reinit_block_writer(struct reftable_writer *w, uint8_t typ) +{ + int block_start = 0; + if (w->next == 0) { + block_start = header_size(writer_version(w)); + } + + strbuf_release(&w->last_key); + block_writer_init(&w->block_writer_data, typ, w->block, + w->opts.block_size, block_start, + hash_size(w->opts.hash_id)); + w->block_writer = &w->block_writer_data; + w->block_writer->restart_interval = w->opts.restart_interval; +} + +struct reftable_writer * +reftable_new_writer(int (*writer_func)(void *, const void *, size_t), + void *writer_arg, struct reftable_write_options *opts) +{ + struct reftable_writer *wp = + reftable_calloc(sizeof(struct reftable_writer)); + strbuf_init(&wp->block_writer_data.last_key, 0); + options_set_defaults(opts); + if (opts->block_size >= (1 << 24)) { + /* TODO - error return? */ + abort(); + } + wp->last_key = reftable_empty_strbuf; + wp->block = reftable_calloc(opts->block_size); + wp->write = writer_func; + wp->write_arg = writer_arg; + wp->opts = *opts; + writer_reinit_block_writer(wp, BLOCK_TYPE_REF); + + return wp; +} + +void reftable_writer_set_limits(struct reftable_writer *w, uint64_t min, + uint64_t max) +{ + w->min_update_index = min; + w->max_update_index = max; +} + +void reftable_writer_free(struct reftable_writer *w) +{ + reftable_free(w->block); + reftable_free(w); +} + +struct obj_index_tree_node { + struct strbuf hash; + uint64_t *offsets; + int offset_len; + int offset_cap; +}; +#define OBJ_INDEX_TREE_NODE_INIT \ + { \ + .hash = STRBUF_INIT \ + } + +static int obj_index_tree_node_compare(const void *a, const void *b) +{ + return strbuf_cmp(&((const struct obj_index_tree_node *)a)->hash, + &((const struct obj_index_tree_node *)b)->hash); +} + +static void writer_index_hash(struct reftable_writer *w, struct strbuf *hash) +{ + uint64_t off = w->next; + + struct obj_index_tree_node want = { .hash = *hash }; + + struct tree_node *node = tree_search(&want, &w->obj_index_tree, + &obj_index_tree_node_compare, 0); + struct obj_index_tree_node *key = NULL; + if (node == NULL) { + struct obj_index_tree_node empty = OBJ_INDEX_TREE_NODE_INIT; + key = reftable_malloc(sizeof(struct obj_index_tree_node)); + *key = empty; + + strbuf_reset(&key->hash); + strbuf_addbuf(&key->hash, hash); + tree_search((void *)key, &w->obj_index_tree, + &obj_index_tree_node_compare, 1); + } else { + key = node->key; + } + + if (key->offset_len > 0 && key->offsets[key->offset_len - 1] == off) { + return; + } + + if (key->offset_len == key->offset_cap) { + key->offset_cap = 2 * key->offset_cap + 1; + key->offsets = reftable_realloc( + key->offsets, sizeof(uint64_t) * key->offset_cap); + } + + key->offsets[key->offset_len++] = off; +} + +static int writer_add_record(struct reftable_writer *w, + struct reftable_record *rec) +{ + int result = -1; + struct strbuf key = STRBUF_INIT; + int err = 0; + reftable_record_key(rec, &key); + if (strbuf_cmp(&w->last_key, &key) >= 0) + goto done; + + strbuf_reset(&w->last_key); + strbuf_addbuf(&w->last_key, &key); + if (w->block_writer == NULL) { + writer_reinit_block_writer(w, reftable_record_type(rec)); + } + + assert(block_writer_type(w->block_writer) == reftable_record_type(rec)); + + if (block_writer_add(w->block_writer, rec) == 0) { + result = 0; + goto done; + } + + err = writer_flush_block(w); + if (err < 0) { + result = err; + goto done; + } + + writer_reinit_block_writer(w, reftable_record_type(rec)); + err = block_writer_add(w->block_writer, rec); + if (err < 0) { + result = err; + goto done; + } + + result = 0; +done: + strbuf_release(&key); + return result; +} + +int reftable_writer_add_ref(struct reftable_writer *w, + struct reftable_ref_record *ref) +{ + struct reftable_record rec = { 0 }; + struct reftable_ref_record copy = *ref; + int err = 0; + + if (ref->ref_name == NULL) + return REFTABLE_API_ERROR; + if (ref->update_index < w->min_update_index || + ref->update_index > w->max_update_index) + return REFTABLE_API_ERROR; + + reftable_record_from_ref(&rec, ©); + copy.update_index -= w->min_update_index; + err = writer_add_record(w, &rec); + if (err < 0) + return err; + + if (!w->opts.skip_index_objects && ref->value != NULL) { + struct strbuf h = STRBUF_INIT; + strbuf_add(&h, (char *)ref->value, hash_size(w->opts.hash_id)); + writer_index_hash(w, &h); + strbuf_release(&h); + } + + if (!w->opts.skip_index_objects && ref->target_value != NULL) { + struct strbuf h = STRBUF_INIT; + strbuf_add(&h, ref->target_value, hash_size(w->opts.hash_id)); + writer_index_hash(w, &h); + } + return 0; +} + +int reftable_writer_add_refs(struct reftable_writer *w, + struct reftable_ref_record *refs, int n) +{ + int err = 0; + int i = 0; + QSORT(refs, n, reftable_ref_record_compare_name); + for (i = 0; err == 0 && i < n; i++) { + err = reftable_writer_add_ref(w, &refs[i]); + } + return err; +} + +int reftable_writer_add_log(struct reftable_writer *w, + struct reftable_log_record *log) +{ + struct reftable_record rec = { 0 }; + char *input_log_message = log->message; + struct strbuf cleaned_message = STRBUF_INIT; + int err; + if (log->ref_name == NULL) + return REFTABLE_API_ERROR; + + if (w->block_writer != NULL && + block_writer_type(w->block_writer) == BLOCK_TYPE_REF) { + int err = writer_finish_public_section(w); + if (err < 0) + return err; + } + + if (!w->opts.exact_log_message && log->message != NULL) { + strbuf_addstr(&cleaned_message, log->message); + while (cleaned_message.len && + cleaned_message.buf[cleaned_message.len - 1] == '\n') + strbuf_setlen(&cleaned_message, + cleaned_message.len - 1); + if (strchr(cleaned_message.buf, '\n')) { + // multiple lines not allowed. + err = REFTABLE_API_ERROR; + goto done; + } + strbuf_addstr(&cleaned_message, "\n"); + log->message = cleaned_message.buf; + } + + w->next -= w->pending_padding; + w->pending_padding = 0; + + reftable_record_from_log(&rec, log); + err = writer_add_record(w, &rec); + +done: + log->message = input_log_message; + strbuf_release(&cleaned_message); + return err; +} + +int reftable_writer_add_logs(struct reftable_writer *w, + struct reftable_log_record *logs, int n) +{ + int err = 0; + int i = 0; + QSORT(logs, n, reftable_log_record_compare_key); + for (i = 0; err == 0 && i < n; i++) { + err = reftable_writer_add_log(w, &logs[i]); + } + return err; +} + +static int writer_finish_section(struct reftable_writer *w) +{ + uint8_t typ = block_writer_type(w->block_writer); + uint64_t index_start = 0; + int max_level = 0; + int threshold = w->opts.unpadded ? 1 : 3; + int before_blocks = w->stats.idx_stats.blocks; + int err = writer_flush_block(w); + int i = 0; + struct reftable_block_stats *bstats = NULL; + if (err < 0) + return err; + + while (w->index_len > threshold) { + struct reftable_index_record *idx = NULL; + int idx_len = 0; + + max_level++; + index_start = w->next; + writer_reinit_block_writer(w, BLOCK_TYPE_INDEX); + + idx = w->index; + idx_len = w->index_len; + + w->index = NULL; + w->index_len = 0; + w->index_cap = 0; + for (i = 0; i < idx_len; i++) { + struct reftable_record rec = { 0 }; + reftable_record_from_index(&rec, idx + i); + if (block_writer_add(w->block_writer, &rec) == 0) { + continue; + } + + err = writer_flush_block(w); + if (err < 0) + return err; + + writer_reinit_block_writer(w, BLOCK_TYPE_INDEX); + + err = block_writer_add(w->block_writer, &rec); + if (err != 0) { + /* write into fresh block should always succeed + */ + abort(); + } + } + for (i = 0; i < idx_len; i++) { + strbuf_release(&idx[i].last_key); + } + reftable_free(idx); + } + + writer_clear_index(w); + + err = writer_flush_block(w); + if (err < 0) + return err; + + bstats = writer_reftable_block_stats(w, typ); + bstats->index_blocks = w->stats.idx_stats.blocks - before_blocks; + bstats->index_offset = index_start; + bstats->max_index_level = max_level; + + /* Reinit lastKey, as the next section can start with any key. */ + w->last_key.len = 0; + + return 0; +} + +struct common_prefix_arg { + struct strbuf *last; + int max; +}; + +static void update_common(void *void_arg, void *key) +{ + struct common_prefix_arg *arg = (struct common_prefix_arg *)void_arg; + struct obj_index_tree_node *entry = (struct obj_index_tree_node *)key; + if (arg->last != NULL) { + int n = common_prefix_size(&entry->hash, arg->last); + if (n > arg->max) { + arg->max = n; + } + } + arg->last = &entry->hash; +} + +struct write_record_arg { + struct reftable_writer *w; + int err; +}; + +static void write_object_record(void *void_arg, void *key) +{ + struct write_record_arg *arg = (struct write_record_arg *)void_arg; + struct obj_index_tree_node *entry = (struct obj_index_tree_node *)key; + struct reftable_obj_record obj_rec = { + .hash_prefix = (uint8_t *)entry->hash.buf, + .hash_prefix_len = arg->w->stats.object_id_len, + .offsets = entry->offsets, + .offset_len = entry->offset_len, + }; + struct reftable_record rec = { 0 }; + if (arg->err < 0) + goto done; + + reftable_record_from_obj(&rec, &obj_rec); + arg->err = block_writer_add(arg->w->block_writer, &rec); + if (arg->err == 0) + goto done; + + arg->err = writer_flush_block(arg->w); + if (arg->err < 0) + goto done; + + writer_reinit_block_writer(arg->w, BLOCK_TYPE_OBJ); + arg->err = block_writer_add(arg->w->block_writer, &rec); + if (arg->err == 0) + goto done; + obj_rec.offset_len = 0; + arg->err = block_writer_add(arg->w->block_writer, &rec); + + /* Should be able to write into a fresh block. */ + assert(arg->err == 0); + +done:; +} + +static void object_record_free(void *void_arg, void *key) +{ + struct obj_index_tree_node *entry = (struct obj_index_tree_node *)key; + + FREE_AND_NULL(entry->offsets); + strbuf_release(&entry->hash); + reftable_free(entry); +} + +static int writer_dump_object_index(struct reftable_writer *w) +{ + struct write_record_arg closure = { .w = w }; + struct common_prefix_arg common = { 0 }; + if (w->obj_index_tree != NULL) { + infix_walk(w->obj_index_tree, &update_common, &common); + } + w->stats.object_id_len = common.max + 1; + + writer_reinit_block_writer(w, BLOCK_TYPE_OBJ); + + if (w->obj_index_tree != NULL) { + infix_walk(w->obj_index_tree, &write_object_record, &closure); + } + + if (closure.err < 0) + return closure.err; + return writer_finish_section(w); +} + +int writer_finish_public_section(struct reftable_writer *w) +{ + uint8_t typ = 0; + int err = 0; + + if (w->block_writer == NULL) + return 0; + + typ = block_writer_type(w->block_writer); + err = writer_finish_section(w); + if (err < 0) + return err; + if (typ == BLOCK_TYPE_REF && !w->opts.skip_index_objects && + w->stats.ref_stats.index_blocks > 0) { + err = writer_dump_object_index(w); + if (err < 0) + return err; + } + + if (w->obj_index_tree != NULL) { + infix_walk(w->obj_index_tree, &object_record_free, NULL); + tree_free(w->obj_index_tree); + w->obj_index_tree = NULL; + } + + w->block_writer = NULL; + return 0; +} + +int reftable_writer_close(struct reftable_writer *w) +{ + uint8_t footer[72]; + uint8_t *p = footer; + int err = writer_finish_public_section(w); + int empty_table = w->next == 0; + if (err != 0) + goto done; + w->pending_padding = 0; + if (empty_table) { + /* Empty tables need a header anyway. */ + uint8_t header[28]; + int n = writer_write_header(w, header); + err = padded_write(w, header, n, 0); + if (err < 0) + goto done; + } + + p += writer_write_header(w, footer); + put_be64(p, w->stats.ref_stats.index_offset); + p += 8; + put_be64(p, (w->stats.obj_stats.offset) << 5 | w->stats.object_id_len); + p += 8; + put_be64(p, w->stats.obj_stats.index_offset); + p += 8; + + put_be64(p, w->stats.log_stats.offset); + p += 8; + put_be64(p, w->stats.log_stats.index_offset); + p += 8; + + put_be32(p, crc32(0, footer, p - footer)); + p += 4; + + err = padded_write(w, footer, footer_size(writer_version(w)), 0); + if (err < 0) + goto done; + + if (empty_table) { + err = REFTABLE_EMPTY_TABLE_ERROR; + goto done; + } + +done: + /* free up memory. */ + block_writer_clear(&w->block_writer_data); + writer_clear_index(w); + strbuf_release(&w->last_key); + return err; +} + +void writer_clear_index(struct reftable_writer *w) +{ + int i = 0; + for (i = 0; i < w->index_len; i++) { + strbuf_release(&w->index[i].last_key); + } + + FREE_AND_NULL(w->index); + w->index_len = 0; + w->index_cap = 0; +} + +const int debug = 0; + +static int writer_flush_nonempty_block(struct reftable_writer *w) +{ + uint8_t typ = block_writer_type(w->block_writer); + struct reftable_block_stats *bstats = + writer_reftable_block_stats(w, typ); + uint64_t block_typ_off = (bstats->blocks == 0) ? w->next : 0; + int raw_bytes = block_writer_finish(w->block_writer); + int padding = 0; + int err = 0; + struct reftable_index_record ir = { .last_key = STRBUF_INIT }; + if (raw_bytes < 0) + return raw_bytes; + + if (!w->opts.unpadded && typ != BLOCK_TYPE_LOG) { + padding = w->opts.block_size - raw_bytes; + } + + if (block_typ_off > 0) { + bstats->offset = block_typ_off; + } + + bstats->entries += w->block_writer->entries; + bstats->restarts += w->block_writer->restart_len; + bstats->blocks++; + w->stats.blocks++; + + if (debug) { + fprintf(stderr, "block %c off %" PRIu64 " sz %d (%d)\n", typ, + w->next, raw_bytes, + get_be24(w->block + w->block_writer->header_off + 1)); + } + + if (w->next == 0) { + writer_write_header(w, w->block); + } + + err = padded_write(w, w->block, raw_bytes, padding); + if (err < 0) + return err; + + if (w->index_cap == w->index_len) { + w->index_cap = 2 * w->index_cap + 1; + w->index = reftable_realloc( + w->index, + sizeof(struct reftable_index_record) * w->index_cap); + } + + ir.offset = w->next; + strbuf_reset(&ir.last_key); + strbuf_addbuf(&ir.last_key, &w->block_writer->last_key); + w->index[w->index_len] = ir; + + w->index_len++; + w->next += padding + raw_bytes; + w->block_writer = NULL; + return 0; +} + +int writer_flush_block(struct reftable_writer *w) +{ + if (w->block_writer == NULL) + return 0; + if (w->block_writer->entries == 0) + return 0; + return writer_flush_nonempty_block(w); +} + +const struct reftable_stats *writer_stats(struct reftable_writer *w) +{ + return &w->stats; +} diff --git a/reftable/writer.h b/reftable/writer.h new file mode 100644 index 00000000000..4b722c3f74c --- /dev/null +++ b/reftable/writer.h @@ -0,0 +1,60 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +#ifndef WRITER_H +#define WRITER_H + +#include "basics.h" +#include "block.h" +#include "reftable.h" +#include "strbuf.h" +#include "tree.h" + +struct reftable_writer { + int (*write)(void *, const void *, size_t); + void *write_arg; + int pending_padding; + struct strbuf last_key; + + /* offset of next block to write. */ + uint64_t next; + uint64_t min_update_index, max_update_index; + struct reftable_write_options opts; + + /* memory buffer for writing */ + uint8_t *block; + + /* writer for the current section. NULL or points to + * block_writer_data */ + struct block_writer *block_writer; + + struct block_writer block_writer_data; + + /* pending index records for the current section */ + struct reftable_index_record *index; + int index_len; + int index_cap; + + /* + tree for use with tsearch; used to populate the 'o' inverse OID + map */ + struct tree_node *obj_index_tree; + + struct reftable_stats stats; +}; + +/* finishes a block, and writes it to storage */ +int writer_flush_block(struct reftable_writer *w); + +/* deallocates memory related to the index */ +void writer_clear_index(struct reftable_writer *w); + +/* finishes writing a 'r' (refs) or 'g' (reflogs) section */ +int writer_finish_public_section(struct reftable_writer *w); + +#endif diff --git a/reftable/zlib-compat.c b/reftable/zlib-compat.c new file mode 100644 index 00000000000..3e0b0f24f1c --- /dev/null +++ b/reftable/zlib-compat.c @@ -0,0 +1,92 @@ +/* taken from zlib's uncompr.c + + commit cacf7f1d4e3d44d871b605da3b647f07d718623f + Author: Mark Adler <madler@xxxxxxxxxxxxxxxxxx> + Date: Sun Jan 15 09:18:46 2017 -0800 + + zlib 1.2.11 + +*/ + +/* + * Copyright (C) 1995-2003, 2010, 2014, 2016 Jean-loup Gailly, Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +#include "system.h" + +/* clang-format off */ + +/* =========================================================================== + Decompresses the source buffer into the destination buffer. *sourceLen is + the byte length of the source buffer. Upon entry, *destLen is the total size + of the destination buffer, which must be large enough to hold the entire + uncompressed data. (The size of the uncompressed data must have been saved + previously by the compressor and transmitted to the decompressor by some + mechanism outside the scope of this compression library.) Upon exit, + *destLen is the size of the decompressed data and *sourceLen is the number + of source bytes consumed. Upon return, source + *sourceLen points to the + first unused input byte. + + uncompress returns Z_OK if success, Z_MEM_ERROR if there was not enough + memory, Z_BUF_ERROR if there was not enough room in the output buffer, or + Z_DATA_ERROR if the input data was corrupted, including if the input data is + an incomplete zlib stream. +*/ +int ZEXPORT uncompress_return_consumed ( + Bytef *dest, + uLongf *destLen, + const Bytef *source, + uLong *sourceLen) { + z_stream stream; + int err; + const uInt max = (uInt)-1; + uLong len, left; + Byte buf[1]; /* for detection of incomplete stream when *destLen == 0 */ + + len = *sourceLen; + if (*destLen) { + left = *destLen; + *destLen = 0; + } + else { + left = 1; + dest = buf; + } + + stream.next_in = (z_const Bytef *)source; + stream.avail_in = 0; + stream.zalloc = (alloc_func)0; + stream.zfree = (free_func)0; + stream.opaque = (voidpf)0; + + err = inflateInit(&stream); + if (err != Z_OK) return err; + + stream.next_out = dest; + stream.avail_out = 0; + + do { + if (stream.avail_out == 0) { + stream.avail_out = left > (uLong)max ? max : (uInt)left; + left -= stream.avail_out; + } + if (stream.avail_in == 0) { + stream.avail_in = len > (uLong)max ? max : (uInt)len; + len -= stream.avail_in; + } + err = inflate(&stream, Z_NO_FLUSH); + } while (err == Z_OK); + + *sourceLen -= len + stream.avail_in; + if (dest != buf) + *destLen = stream.total_out; + else if (stream.total_out && err == Z_BUF_ERROR) + left = 1; + + inflateEnd(&stream); + return err == Z_STREAM_END ? Z_OK : + err == Z_NEED_DICT ? Z_DATA_ERROR : + err == Z_BUF_ERROR && left + stream.avail_out ? Z_DATA_ERROR : + err; +} -- gitgitgadget