Move index version 2 specific functions to their own file. The non-index
specific functions will be in read-cache.c, while the index version 2
specific functions will be in read-cache-v2.c.
Helped-by: Nguyen Thai Ngoc Duy <pclouds@xxxxxxxxx>
Signed-off-by: Thomas Gummerer <t.gummerer@xxxxxxxxx>
---
Makefile | 2 +
builtin/apply.c | 2 +
builtin/update-index.c | 2 +-
cache.h | 13 +-
read-cache-v2.c | 553 ++++++++++++++++++++++++++++++++++++++++++++++
read-cache.c | 585 +++++--------------------------------------------
read-cache.h | 63 ++++++
test-index-version.c | 6 +
unpack-trees.c | 3 +-
9 files changed, 683 insertions(+), 546 deletions(-)
create mode 100644 read-cache-v2.c
create mode 100644 read-cache.h
diff --git a/Makefile b/Makefile
index af847f8..5c28777 100644
--- a/Makefile
+++ b/Makefile
@@ -705,6 +705,7 @@ LIB_H += progress.h
LIB_H += prompt.h
LIB_H += quote.h
LIB_H += reachable.h
+LIB_H += read-cache.h
LIB_H += reflog-walk.h
LIB_H += refs.h
LIB_H += remote.h
@@ -849,6 +850,7 @@ LIB_OBJS += prompt.o
LIB_OBJS += quote.o
LIB_OBJS += reachable.o
LIB_OBJS += read-cache.o
+LIB_OBJS += read-cache-v2.o
LIB_OBJS += reflog-walk.o
LIB_OBJS += refs.o
LIB_OBJS += remote.o
diff --git a/builtin/apply.c b/builtin/apply.c
index ef32e4f..a954147 100644
--- a/builtin/apply.c
+++ b/builtin/apply.c
@@ -3682,6 +3682,8 @@ static void build_fake_ancestor(struct patch *list, const char *filename)
die ("Could not add %s to temporary index", name);
}
+ if (!result.initialized)
+ initialize_index(&result, 0);
fd = open(filename, O_WRONLY | O_CREAT, 0666);
if (fd < 0 || write_index(&result, fd) || close(fd))
die ("Could not write temporary index to %s", filename);
diff --git a/builtin/update-index.c b/builtin/update-index.c
index e3a10d7..c5bb889 100644
--- a/builtin/update-index.c
+++ b/builtin/update-index.c
@@ -863,7 +863,7 @@ int cmd_update_index(int argc, const char **argv, const char *prefix)
if (the_index.version != preferred_index_format)
active_cache_changed = 1;
- the_index.version = preferred_index_format;
+ change_cache_version(preferred_index_format);
}
if (read_from_stdin) {
diff --git a/cache.h b/cache.h
index ce377e1..290e26d 100644
--- a/cache.h
+++ b/cache.h
@@ -95,16 +95,8 @@ unsigned long git_deflate_bound(git_zstream *, unsigned long);
*/
#define DEFAULT_GIT_PORT 9418
-/*
- * Basic data structures for the directory cache
- */
#define CACHE_SIGNATURE 0x44495243 /* "DIRC" */
-struct cache_header {
- uint32_t hdr_signature;
- uint32_t hdr_version;
- uint32_t hdr_entries;
-};
#define INDEX_FORMAT_LB 2
#define INDEX_FORMAT_UB 4
@@ -279,6 +271,7 @@ struct index_state {
initialized : 1;
struct hash_table name_hash;
struct hash_table dir_hash;
+ struct index_ops *ops;
};
extern struct index_state the_index;
@@ -296,6 +289,8 @@ extern void free_name_hash(struct index_state *istate);
#define active_cache_changed (the_index.cache_changed)
#define active_cache_tree (the_index.cache_tree)
+#define initialize_cache() initialize_index(&the_index, 0)
+#define change_cache_version(version) change_index_version(&the_index, (version))
#define read_cache() read_index(&the_index)
#define read_cache_from(path) read_index_from(&the_index, (path))
#define read_cache_preload(pathspec) read_index_preload(&the_index, (pathspec))
@@ -455,6 +450,8 @@ extern void sanitize_stdfds(void);
} while (0)
/* Initialize and use the cache information */
+extern void initialize_index(struct index_state *istate, int version);
+extern void change_index_version(struct index_state *istate, int version);
extern int read_index(struct index_state *);
extern int read_index_preload(struct index_state *, const struct pathspec *pathspec);
extern int read_index_from(struct index_state *, const char *path);
diff --git a/read-cache-v2.c b/read-cache-v2.c
new file mode 100644
index 0000000..a7d076c
--- /dev/null
+++ b/read-cache-v2.c
@@ -0,0 +1,553 @@
+#include "cache.h"
+#include "read-cache.h"
+#include "resolve-undo.h"
+#include "cache-tree.h"
+#include "varint.h"
+
+/* Mask for the name length in ce_flags in the on-disk index */
+#define CE_NAMEMASK (0x0fff)
+
+/*****************************************************************
+ * Index File I/O
+ *****************************************************************/
+
+/*
+ * dev/ino/uid/gid/size are also just tracked to the low 32 bits
+ * Again - this is just a (very strong in practice) heuristic that
+ * the inode hasn't changed.
+ *
+ * We save the fields in big-endian order to allow using the
+ * index file over NFS transparently.
+ */
+struct ondisk_cache_entry {
+ struct cache_time ctime;
+ struct cache_time mtime;
+ uint32_t dev;
+ uint32_t ino;
+ uint32_t mode;
+ uint32_t uid;
+ uint32_t gid;
+ uint32_t size;
+ unsigned char sha1[20];
+ uint16_t flags;
+ char name[FLEX_ARRAY]; /* more */
+};
+
+/*
+ * This struct is used when CE_EXTENDED bit is 1
+ * The struct must match ondisk_cache_entry exactly from
+ * ctime till flags
+ */
+struct ondisk_cache_entry_extended {
+ struct cache_time ctime;
+ struct cache_time mtime;
+ uint32_t dev;
+ uint32_t ino;
+ uint32_t mode;
+ uint32_t uid;
+ uint32_t gid;
+ uint32_t size;
+ unsigned char sha1[20];
+ uint16_t flags;
+ uint16_t flags2;
+ char name[FLEX_ARRAY]; /* more */
+};
+
+/* These are only used for v3 or lower */
+#define align_flex_name(STRUCT,len) ((offsetof(struct STRUCT,name) + (len) + 8) & ~7)
+#define ondisk_cache_entry_size(len) align_flex_name(ondisk_cache_entry,len)
+#define ondisk_cache_entry_extended_size(len) align_flex_name(ondisk_cache_entry_extended,len)
+#define ondisk_ce_size(ce) (((ce)->ce_flags & CE_EXTENDED) ? \
+ ondisk_cache_entry_extended_size(ce_namelen(ce)) : \
+ ondisk_cache_entry_size(ce_namelen(ce)))
+
+static int verify_hdr(void *mmap, unsigned long size)
+{
+ git_SHA_CTX c;
+ unsigned char sha1[20];
+
+ if (size < + sizeof(struct cache_header) + 20)
+ die("index file smaller than expected");
+
+ git_SHA1_Init(&c);
+ git_SHA1_Update(&c, mmap, size - 20);
+ git_SHA1_Final(sha1, &c);
+ if (hashcmp(sha1, (unsigned char *)mmap + size - 20))
+ return error("bad index file sha1 signature");
+ return 0;
+}
+
+static int match_stat_basic(const struct cache_entry *ce,
+ struct stat *st, int changed)
+{
+ changed |= match_stat_data(&ce->ce_stat_data, st);
+
+ /* Racily smudged entry? */
+ if (!ce->ce_stat_data.sd_size) {
+ if (!is_empty_blob_sha1(ce->sha1))
+ changed |= DATA_CHANGED;
+ }
+ return changed;
+}
+
+static struct cache_entry *cache_entry_from_ondisk(struct ondisk_cache_entry *ondisk,
+ unsigned int flags,
+ const char *name,
+ size_t len)
+{
+ struct cache_entry *ce = xmalloc(cache_entry_size(len));
+
+ ce->ce_stat_data.sd_ctime.sec = ntoh_l(ondisk->ctime.sec);
+ ce->ce_stat_data.sd_mtime.sec = ntoh_l(ondisk->mtime.sec);
+ ce->ce_stat_data.sd_ctime.nsec = ntoh_l(ondisk->ctime.nsec);
+ ce->ce_stat_data.sd_mtime.nsec = ntoh_l(ondisk->mtime.nsec);
+ ce->ce_stat_data.sd_dev = ntoh_l(ondisk->dev);
+ ce->ce_stat_data.sd_ino = ntoh_l(ondisk->ino);
+ ce->ce_mode = ntoh_l(ondisk->mode);
+ ce->ce_stat_data.sd_uid = ntoh_l(ondisk->uid);
+ ce->ce_stat_data.sd_gid = ntoh_l(ondisk->gid);
+ ce->ce_stat_data.sd_size = ntoh_l(ondisk->size);
+ ce->ce_flags = flags & ~CE_NAMEMASK;
+ ce->ce_namelen = len;
+ hashcpy(ce->sha1, ondisk->sha1);
+ memcpy(ce->name, name, len);
+ ce->name[len] = '\0';
+ return ce;
+}
+
+/*
+ * Adjacent cache entries tend to share the leading paths, so it makes
+ * sense to only store the differences in later entries. In the v4
+ * on-disk format of the index, each on-disk cache entry stores the
+ * number of bytes to be stripped from the end of the previous name,
+ * and the bytes to append to the result, to come up with its name.
+ */
+static unsigned long expand_name_field(struct strbuf *name, const char *cp_)
+{
+ const unsigned char *ep, *cp = (const unsigned char *)cp_;
+ size_t len = decode_varint(&cp);
+
+ if (name->len < len)
+ die("malformed name field in the index");
+ strbuf_remove(name, name->len - len, len);
+ for (ep = cp; *ep; ep++)
+ ; /* find the end */
+ strbuf_add(name, cp, ep - cp);
+ return (const char *)ep + 1 - cp_;
+}
+
+static struct cache_entry *create_from_disk(struct ondisk_cache_entry *ondisk,
+ unsigned long *ent_size,
+ struct strbuf *previous_name)
+{
+ struct cache_entry *ce;
+ size_t len;
+ const char *name;
+ unsigned int flags;
+
+ /* On-disk flags are just 16 bits */
+ flags = ntoh_s(ondisk->flags);
+ len = flags & CE_NAMEMASK;
+
+ if (flags & CE_EXTENDED) {
+ struct ondisk_cache_entry_extended *ondisk2;
+ int extended_flags;
+ ondisk2 = (struct ondisk_cache_entry_extended *)ondisk;
+ extended_flags = ntoh_s(ondisk2->flags2) << 16;
+ /* We do not yet understand any bit out of CE_EXTENDED_FLAGS */
+ if (extended_flags & ~CE_EXTENDED_FLAGS)
+ die("Unknown index entry format %08x", extended_flags);
+ flags |= extended_flags;
+ name = ondisk2->name;
+ }
+ else
+ name = ondisk->name;
+
+ if (!previous_name) {
+ /* v3 and earlier */
+ if (len == CE_NAMEMASK)
+ len = strlen(name);
+ ce = cache_entry_from_ondisk(ondisk, flags, name, len);
+
+ *ent_size = ondisk_ce_size(ce);
+ } else {
+ unsigned long consumed;
+ consumed = expand_name_field(previous_name, name);
+ ce = cache_entry_from_ondisk(ondisk, flags,
+ previous_name->buf,
+ previous_name->len);
+
+ *ent_size = (name - ((char *)ondisk)) + consumed;
+ }
+ return ce;
+}
+
+static int read_index_extension(struct index_state *istate,
+ const char *ext, void *data, unsigned long sz)
+{
+ switch (CACHE_EXT(ext)) {
+ case CACHE_EXT_TREE:
+ istate->cache_tree = cache_tree_read(data, sz);
+ break;
+ case CACHE_EXT_RESOLVE_UNDO:
+ istate->resolve_undo = resolve_undo_read(data, sz);
+ break;
+ default:
+ if (*ext < 'A' || 'Z' < *ext)
+ return error("index uses %.4s extension, which we do not understand",
+ ext);
+ fprintf(stderr, "ignoring %.4s extension\n", ext);
+ break;
+ }
+ return 0;
+}
+
+static int read_index_v2(struct index_state *istate, void *mmap,
+ unsigned long mmap_size)
+{
+ int i;
+ unsigned long src_offset;
+ struct cache_header *hdr;
+ struct strbuf previous_name_buf = STRBUF_INIT, *previous_name;
+
+ hdr = mmap;
+ istate->cache_nr = ntohl(hdr->hdr_entries);
+ istate->cache_alloc = alloc_nr(istate->cache_nr);
+ istate->cache = xcalloc(istate->cache_alloc, sizeof(struct cache_entry *));
+
+ if (istate->version == 4)
+ previous_name = &previous_name_buf;
+ else
+ previous_name = NULL;
+
+ src_offset = sizeof(*hdr);
+ for (i = 0; i < istate->cache_nr; i++) {
+ struct ondisk_cache_entry *disk_ce;
+ struct cache_entry *ce;
+ unsigned long consumed;
+
+ disk_ce = (struct ondisk_cache_entry *)((char *)mmap + src_offset);
+ ce = create_from_disk(disk_ce, &consumed, previous_name);
+ set_index_entry(istate, i, ce);
+
+ src_offset += consumed;
+ }
+ strbuf_release(&previous_name_buf);
+
+ while (src_offset <= mmap_size - 20 - 8) {
+ /* After an array of active_nr index entries,
+ * there can be arbitrary number of extended
+ * sections, each of which is prefixed with
+ * extension name (4-byte) and section length
+ * in 4-byte network byte order.
+ */
+ uint32_t extsize;
+ memcpy(&extsize, (char *)mmap + src_offset + 4, 4);
+ extsize = ntohl(extsize);
+ if (read_index_extension(istate,
+ (const char *) mmap + src_offset,
+ (char *) mmap + src_offset + 8,
+ extsize) < 0)
+ goto unmap;
+ src_offset += 8;
+ src_offset += extsize;
+ }
+ return 0;
+unmap:
+ munmap(mmap, mmap_size);
+ die("index file corrupt");
+}
+
+#define WRITE_BUFFER_SIZE 8192
+static unsigned char write_buffer[WRITE_BUFFER_SIZE];
+static unsigned long write_buffer_len;
+
+static int ce_write_flush(git_SHA_CTX *context, int fd)
+{
+ unsigned int buffered = write_buffer_len;
+ if (buffered) {
+ git_SHA1_Update(context, write_buffer, buffered);
+ if (write_in_full(fd, write_buffer, buffered) != buffered)
+ return -1;
+ write_buffer_len = 0;
+ }
+ return 0;
+}
+
+static int ce_write(git_SHA_CTX *context, int fd, void *data, unsigned int len)
+{
+ while (len) {
+ unsigned int buffered = write_buffer_len;
+ unsigned int partial = WRITE_BUFFER_SIZE - buffered;
+ if (partial > len)
+ partial = len;
+ memcpy(write_buffer + buffered, data, partial);
+ buffered += partial;
+ if (buffered == WRITE_BUFFER_SIZE) {
+ write_buffer_len = buffered;
+ if (ce_write_flush(context, fd))
+ return -1;
+ buffered = 0;
+ }
+ write_buffer_len = buffered;
+ len -= partial;
+ data = (char *) data + partial;
+ }
+ return 0;
+}
+
+static int write_index_ext_header(git_SHA_CTX *context, int fd,
+ unsigned int ext, unsigned int sz)
+{
+ ext = htonl(ext);
+ sz = htonl(sz);
+ return ((ce_write(context, fd, &ext, 4) < 0) ||
+ (ce_write(context, fd, &sz, 4) < 0)) ? -1 : 0;
+}
+
+static int ce_flush(git_SHA_CTX *context, int fd)
+{
+ unsigned int left = write_buffer_len;
+
+ if (left) {
+ write_buffer_len = 0;
+ git_SHA1_Update(context, write_buffer, left);
+ }
+
+ /* Flush first if not enough space for SHA1 signature */
+ if (left + 20 > WRITE_BUFFER_SIZE) {
+ if (write_in_full(fd, write_buffer, left) != left)
+ return -1;
+ left = 0;
+ }
+
+ /* Append the SHA1 signature at the end */
+ git_SHA1_Final(write_buffer + left, context);
+ left += 20;
+ return (write_in_full(fd, write_buffer, left) != left) ? -1 : 0;
+}
+
+static void ce_smudge_racily_clean_entry(struct index_state *istate, struct cache_entry *ce)
+{
+ /*
+ * The only thing we care about in this function is to smudge the
+ * falsely clean entry due to touch-update-touch race, so we leave
+ * everything else as they are. We are called for entries whose
+ * ce_stat_data.sd_mtime match the index file mtime.
+ *
+ * Note that this actually does not do much for gitlinks, for
+ * which ce_match_stat_basic() always goes to the actual
+ * contents. The caller checks with is_racy_timestamp() which
+ * always says "no" for gitlinks, so we are not called for them ;-)
+ */
+ struct stat st;
+
+ if (lstat(ce->name, &st) < 0)
+ return;
+ if (ce_match_stat_basic(istate, ce, &st))
+ return;
+ if (ce_modified_check_fs(ce, &st)) {
+ /* This is "racily clean"; smudge it. Note that this
+ * is a tricky code. At first glance, it may appear
+ * that it can break with this sequence:
+ *
+ * $ echo xyzzy >frotz
+ * $ git-update-index --add frotz
+ * $ : >frotz
+ * $ sleep 3
+ * $ echo filfre >nitfol
+ * $ git-update-index --add nitfol
+ *
+ * but it does not. When the second update-index runs,
+ * it notices that the entry "frotz" has the same timestamp
+ * as index, and if we were to smudge it by resetting its
+ * size to zero here, then the object name recorded
+ * in index is the 6-byte file but the cached stat information
+ * becomes zero --- which would then match what we would
+ * obtain from the filesystem next time we stat("frotz").
+ *
+ * However, the second update-index, before calling
+ * this function, notices that the cached size is 6
+ * bytes and what is on the filesystem is an empty
+ * file, and never calls us, so the cached size information
+ * for "frotz" stays 6 which does not match the filesystem.
+ */
+ ce->ce_stat_data.sd_size = 0;
+ }
+}
+
+/* Copy miscellaneous fields but not the name */
+static char *copy_cache_entry_to_ondisk(struct ondisk_cache_entry *ondisk,
+ struct cache_entry *ce)
+{
+ short flags;
+
+ ondisk->ctime.sec = htonl(ce->ce_stat_data.sd_ctime.sec);
+ ondisk->mtime.sec = htonl(ce->ce_stat_data.sd_mtime.sec);
+ ondisk->ctime.nsec = htonl(ce->ce_stat_data.sd_ctime.nsec);
+ ondisk->mtime.nsec = htonl(ce->ce_stat_data.sd_mtime.nsec);
+ ondisk->dev = htonl(ce->ce_stat_data.sd_dev);
+ ondisk->ino = htonl(ce->ce_stat_data.sd_ino);
+ ondisk->mode = htonl(ce->ce_mode);
+ ondisk->uid = htonl(ce->ce_stat_data.sd_uid);
+ ondisk->gid = htonl(ce->ce_stat_data.sd_gid);
+ ondisk->size = htonl(ce->ce_stat_data.sd_size);
+ hashcpy(ondisk->sha1, ce->sha1);
+
+ flags = ce->ce_flags;
+ flags |= (ce_namelen(ce) >= CE_NAMEMASK ? CE_NAMEMASK : ce_namelen(ce));
+ ondisk->flags = htons(flags);
+ if (ce->ce_flags & CE_EXTENDED) {
+ struct ondisk_cache_entry_extended *ondisk2;
+ ondisk2 = (struct ondisk_cache_entry_extended *)ondisk;
+ ondisk2->flags2 = htons((ce->ce_flags & CE_EXTENDED_FLAGS) >> 16);
+ return ondisk2->name;
+ }
+ else {
+ return ondisk->name;
+ }
+}
+
+static int ce_write_entry(git_SHA_CTX *c, int fd, struct cache_entry *ce,
+ struct strbuf *previous_name)
+{
+ int size;
+ struct ondisk_cache_entry *ondisk;
+ char *name;
+ int result;
+
+ if (!previous_name) {
+ size = ondisk_ce_size(ce);
+ ondisk = xcalloc(1, size);
+ name = copy_cache_entry_to_ondisk(ondisk, ce);
+ memcpy(name, ce->name, ce_namelen(ce));
+ } else {
+ int common, to_remove, prefix_size;
+ unsigned char to_remove_vi[16];
+ for (common = 0;
+ (ce->name[common] &&
+ common < previous_name->len &&
+ ce->name[common] == previous_name->buf[common]);
+ common++)
+ ; /* still matching */
+ to_remove = previous_name->len - common;
+ prefix_size = encode_varint(to_remove, to_remove_vi);
+
+ if (ce->ce_flags & CE_EXTENDED)
+ size = offsetof(struct ondisk_cache_entry_extended, name);
+ else
+ size = offsetof(struct ondisk_cache_entry, name);
+ size += prefix_size + (ce_namelen(ce) - common + 1);
+
+ ondisk = xcalloc(1, size);
+ name = copy_cache_entry_to_ondisk(ondisk, ce);
+ memcpy(name, to_remove_vi, prefix_size);
+ memcpy(name + prefix_size, ce->name + common, ce_namelen(ce) - common);
+
+ strbuf_splice(previous_name, common, to_remove,
+ ce->name + common, ce_namelen(ce) - common);
+ }
+
+ result = ce_write(c, fd, ondisk, size);
+ free(ondisk);
+ return result;
+}
+
+static int write_index_v2(struct index_state *istate, int newfd)
+{
+ git_SHA_CTX c;
+ struct cache_header hdr;
+ int i, err, removed, extended, hdr_version;
+ struct cache_entry **cache = istate->cache;
+ int entries = istate->cache_nr;
+ struct stat st;
+ struct strbuf previous_name_buf = STRBUF_INIT, *previous_name;
+
+ for (i = removed = extended = 0; i < entries; i++) {
+ if (cache[i]->ce_flags & CE_REMOVE)
+ removed++;
+
+ /* reduce extended entries if possible */
+ cache[i]->ce_flags &= ~CE_EXTENDED;
+ if (cache[i]->ce_flags & CE_EXTENDED_FLAGS) {
+ extended++;
+ cache[i]->ce_flags |= CE_EXTENDED;
+ }
+ }
+
+ if (!istate->version)
+ istate->version = INDEX_FORMAT_DEFAULT;
+
+ /* demote version 3 to version 2 when the latter suffices */
+ if (istate->version == 3 || istate->version == 2)
+ istate->version = extended ? 3 : 2;
+
+ hdr_version = istate->version;
+
+ hdr.hdr_signature = htonl(CACHE_SIGNATURE);
+ hdr.hdr_version = htonl(hdr_version);
+ hdr.hdr_entries = htonl(entries - removed);
+
+ git_SHA1_Init(&c);
+ if (ce_write(&c, newfd, &hdr, sizeof(hdr)) < 0)
+ return -1;
+
+ previous_name = (hdr_version == 4) ? &previous_name_buf : NULL;
+ for (i = 0; i < entries; i++) {
+ struct cache_entry *ce = cache[i];
+ if (ce->ce_flags & CE_REMOVE)
+ continue;
+ if (!ce_uptodate(ce) && is_racy_timestamp(istate, ce))
+ ce_smudge_racily_clean_entry(istate, ce);
+ if (is_null_sha1(ce->sha1)) {
+ static const char msg[] = "cache entry has null sha1: %s";
+ static int allow = -1;
+
+ if (allow < 0)
+ allow = git_env_bool("GIT_ALLOW_NULL_SHA1", 0);
+ if (allow)
+ warning(msg, ce->name);
+ else
+ return error(msg, ce->name);
+ }
+ if (ce_write_entry(&c, newfd, ce, previous_name) < 0)
+ return -1;
+ }
+ strbuf_release(&previous_name_buf);
+
+ /* Write extension data here */
+ if (istate->cache_tree) {
+ struct strbuf sb = STRBUF_INIT;
+
+ cache_tree_write(&sb, istate->cache_tree);
+ err = write_index_ext_header(&c, newfd, CACHE_EXT_TREE, sb.len) < 0
+ || ce_write(&c, newfd, sb.buf, sb.len) < 0;
+ strbuf_release(&sb);
+ if (err)
+ return -1;
+ }
+ if (istate->resolve_undo) {
+ struct strbuf sb = STRBUF_INIT;
+
+ resolve_undo_write(&sb, istate->resolve_undo);
+ err = write_index_ext_header(&c, newfd, CACHE_EXT_RESOLVE_UNDO,
+ sb.len) < 0
+ || ce_write(&c, newfd, sb.buf, sb.len) < 0;
+ strbuf_release(&sb);
+ if (err)
+ return -1;
+ }
+
+ if (ce_flush(&c, newfd) || fstat(newfd, &st))
+ return -1;
+ istate->timestamp.sec = (unsigned int)st.st_mtime;
+ istate->timestamp.nsec = ST_MTIME_NSEC(st);
+ return 0;
+}
+
+struct index_ops v2_ops = {
+ match_stat_basic,
+ verify_hdr,
+ read_index_v2,
+ write_index_v2
+};
diff --git a/read-cache.c b/read-cache.c
index 5a8f405..e081084 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -5,6 +5,7 @@
*/
#define NO_THE_INDEX_COMPATIBILITY_MACROS
#include "cache.h"
+#include "read-cache.h"
#include "cache-tree.h"
#include "refs.h"
#include "dir.h"
@@ -17,26 +18,9 @@
static struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really);
-/* Mask for the name length in ce_flags in the on-disk index */
-
-#define CE_NAMEMASK (0x0fff)
-
-/* Index extensions.
- *
- * The first letter should be 'A'..'Z' for extensions that are not
- * necessary for a correct operation (i.e. optimization data).
- * When new extensions are added that _needs_ to be understood in
- * order to correctly interpret the index file, pick character that
- * is outside the range, to cause the reader to abort.
- */
-
-#define CACHE_EXT(s) ( (s[0]<<24)|(s[1]<<16)|(s[2]<<8)|(s[3]) )
-#define CACHE_EXT_TREE 0x54524545 /* "TREE" */
-#define CACHE_EXT_RESOLVE_UNDO 0x52455543 /* "REUC" */
-
struct index_state the_index;
-static void set_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
+void set_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
{
istate->cache[nr] = ce;
add_name_hash(istate, ce);
@@ -190,7 +174,7 @@ static int ce_compare_gitlink(const struct cache_entry *ce)
return hashcmp(sha1, ce->sha1);
}
-static int ce_modified_check_fs(const struct cache_entry *ce, struct stat *st)
+int ce_modified_check_fs(const struct cache_entry *ce, struct stat *st)
{
switch (st->st_mode & S_IFMT) {
case S_IFREG:
@@ -210,7 +194,18 @@ static int ce_modified_check_fs(const struct cache_entry *ce, struct stat *st)
return 0;
}
-static int ce_match_stat_basic(const struct cache_entry *ce, struct stat *st)
+/*
+ * Check if the reading/writing operations are set and set them
+ * to the correct version
+ */
+static void set_istate_ops(struct index_state *istate)
+{
+ if (istate->version >= 2 && istate->version <= 4)
+ istate->ops = &v2_ops;
+}
+
+int ce_match_stat_basic(const struct index_state *istate,
+ const struct cache_entry *ce, struct stat *st)
{
unsigned int changed = 0;
@@ -243,19 +238,13 @@ static int ce_match_stat_basic(const struct cache_entry *ce, struct stat *st)
die("internal error: ce_mode is %o", ce->ce_mode);
}
- changed |= match_stat_data(&ce->ce_stat_data, st);
-
- /* Racily smudged entry? */
- if (!ce->ce_stat_data.sd_size) {
- if (!is_empty_blob_sha1(ce->sha1))
- changed |= DATA_CHANGED;
- }
-
+ changed = istate->ops->match_stat_basic(ce, st, changed);
return changed;
}
-static int is_racy_timestamp(const struct index_state *istate,
- const struct cache_entry *ce)
+
+int is_racy_timestamp(const struct index_state *istate,
+ const struct cache_entry *ce)
{
return (!S_ISGITLINK(ce->ce_mode) &&
istate->timestamp.sec &&
@@ -298,7 +287,7 @@ int ie_match_stat(const struct index_state *istate,
if (ce->ce_flags & CE_INTENT_TO_ADD)
return DATA_CHANGED | TYPE_CHANGED | MODE_CHANGED;
- changed = ce_match_stat_basic(ce, st);
+ changed = ce_match_stat_basic(istate, ce, st);
/*
* Within 1 second of this sequence:
@@ -982,6 +971,8 @@ int add_index_entry(struct index_state *istate, struct cache_entry *ce, int opti
{
int pos;
+ if (!istate->initialized)
+ initialize_index(istate, INDEX_FORMAT_DEFAULT);
if (option & ADD_CACHE_JUST_APPEND)
pos = istate->cache_nr;
else {
@@ -1212,13 +1203,25 @@ static struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int reall
return refresh_cache_ent(&the_index, ce, really, NULL, NULL);
}
+void initialize_index(struct index_state *istate, int version)
+{
+ istate->initialized = 1;
+ if (!version)
+ version = INDEX_FORMAT_DEFAULT;
+ istate->version = version;
+ set_istate_ops(istate);
+}
+
+void change_index_version(struct index_state *istate, int version)
+{
+ istate->version = version;
+ set_istate_ops(istate);
+}
/*****************************************************************
* Index File I/O
*****************************************************************/
-#define INDEX_FORMAT_DEFAULT 3
-
/*
* dev/ino/uid/gid/size are also just tracked to the low 32 bits
* Again - this is just a (very strong in practice) heuristic that
@@ -1269,7 +1272,8 @@ struct ondisk_cache_entry_extended {
ondisk_cache_entry_extended_size(ce_namelen(ce)) : \
ondisk_cache_entry_size(ce_namelen(ce)))
-static int verify_hdr_version(struct cache_header *hdr, unsigned long size)
+static int verify_hdr_version(struct index_state *istate,
+ struct cache_header *hdr, unsigned long size)
{
int hdr_version;
@@ -1278,42 +1282,7 @@ static int verify_hdr_version(struct cache_header *hdr, unsigned long size)
hdr_version = ntohl(hdr->hdr_version);
if (hdr_version < INDEX_FORMAT_LB || INDEX_FORMAT_UB < hdr_version)
return error("bad index version %d", hdr_version);
- return 0;
-}
-
-static int verify_hdr(void *mmap, unsigned long size)
-{
- git_SHA_CTX c;
- unsigned char sha1[20];
-
- if (size < sizeof(struct cache_header) + 20)
- die("index file smaller than expected");
-
- git_SHA1_Init(&c);
- git_SHA1_Update(&c, mmap, size - 20);
- git_SHA1_Final(sha1, &c);
- if (hashcmp(sha1, (unsigned char *)mmap + size - 20))
- return error("bad index file sha1 signature");
- return 0;
-}
-
-static int read_index_extension(struct index_state *istate,
- const char *ext, void *data, unsigned long sz)
-{
- switch (CACHE_EXT(ext)) {
- case CACHE_EXT_TREE:
- istate->cache_tree = cache_tree_read(data, sz);
- break;
- case CACHE_EXT_RESOLVE_UNDO:
- istate->resolve_undo = resolve_undo_read(data, sz);
- break;
- default:
- if (*ext < 'A' || 'Z' < *ext)
- return error("index uses %.4s extension, which we do not understand",
- ext);
- fprintf(stderr, "ignoring %.4s extension\n", ext);
- break;
- }
+ initialize_index(istate, hdr_version);
return 0;
}
@@ -1322,176 +1291,6 @@ int read_index(struct index_state *istate)
return read_index_from(istate, get_index_file());
}
-#ifndef NEEDS_ALIGNED_ACCESS
-#define ntoh_s(var) ntohs(var)
-#define ntoh_l(var) ntohl(var)
-#else
-static inline uint16_t ntoh_s_force_align(void *p)
-{
- uint16_t x;
- memcpy(&x, p, sizeof(x));
- return ntohs(x);
-}
-static inline uint32_t ntoh_l_force_align(void *p)
-{
- uint32_t x;
- memcpy(&x, p, sizeof(x));
- return ntohl(x);
-}
-#define ntoh_s(var) ntoh_s_force_align(&(var))
-#define ntoh_l(var) ntoh_l_force_align(&(var))
-#endif
-
-static struct cache_entry *cache_entry_from_ondisk(struct ondisk_cache_entry *ondisk,
- unsigned int flags,
- const char *name,
- size_t len)
-{
- struct cache_entry *ce = xmalloc(cache_entry_size(len));
-
- ce->ce_stat_data.sd_ctime.sec = ntoh_l(ondisk->ctime.sec);
- ce->ce_stat_data.sd_mtime.sec = ntoh_l(ondisk->mtime.sec);
- ce->ce_stat_data.sd_ctime.nsec = ntoh_l(ondisk->ctime.nsec);
- ce->ce_stat_data.sd_mtime.nsec = ntoh_l(ondisk->mtime.nsec);
- ce->ce_stat_data.sd_dev = ntoh_l(ondisk->dev);
- ce->ce_stat_data.sd_ino = ntoh_l(ondisk->ino);
- ce->ce_mode = ntoh_l(ondisk->mode);
- ce->ce_stat_data.sd_uid = ntoh_l(ondisk->uid);
- ce->ce_stat_data.sd_gid = ntoh_l(ondisk->gid);
- ce->ce_stat_data.sd_size = ntoh_l(ondisk->size);
- ce->ce_flags = flags & ~CE_NAMEMASK;
- ce->ce_namelen = len;
- hashcpy(ce->sha1, ondisk->sha1);
- memcpy(ce->name, name, len);
- ce->name[len] = '\0';
- return ce;
-}
-
-/*
- * Adjacent cache entries tend to share the leading paths, so it makes
- * sense to only store the differences in later entries. In the v4
- * on-disk format of the index, each on-disk cache entry stores the
- * number of bytes to be stripped from the end of the previous name,
- * and the bytes to append to the result, to come up with its name.
- */
-static unsigned long expand_name_field(struct strbuf *name, const char *cp_)
-{
- const unsigned char *ep, *cp = (const unsigned char *)cp_;
- size_t len = decode_varint(&cp);
-
- if (name->len < len)
- die("malformed name field in the index");
- strbuf_remove(name, name->len - len, len);
- for (ep = cp; *ep; ep++)
- ; /* find the end */
- strbuf_add(name, cp, ep - cp);
- return (const char *)ep + 1 - cp_;
-}
-
-static struct cache_entry *create_from_disk(struct ondisk_cache_entry *ondisk,
- unsigned long *ent_size,
- struct strbuf *previous_name)
-{
- struct cache_entry *ce;
- size_t len;
- const char *name;
- unsigned int flags;
-
- /* On-disk flags are just 16 bits */
- flags = ntoh_s(ondisk->flags);
- len = flags & CE_NAMEMASK;
-
- if (flags & CE_EXTENDED) {
- struct ondisk_cache_entry_extended *ondisk2;
- int extended_flags;
- ondisk2 = (struct ondisk_cache_entry_extended *)ondisk;
- extended_flags = ntoh_s(ondisk2->flags2) << 16;
- /* We do not yet understand any bit out of CE_EXTENDED_FLAGS */
- if (extended_flags & ~CE_EXTENDED_FLAGS)
- die("Unknown index entry format %08x", extended_flags);
- flags |= extended_flags;
- name = ondisk2->name;
- }
- else
- name = ondisk->name;
-
- if (!previous_name) {
- /* v3 and earlier */
- if (len == CE_NAMEMASK)
- len = strlen(name);
- ce = cache_entry_from_ondisk(ondisk, flags, name, len);
-
- *ent_size = ondisk_ce_size(ce);
- } else {
- unsigned long consumed;
- consumed = expand_name_field(previous_name, name);
- ce = cache_entry_from_ondisk(ondisk, flags,
- previous_name->buf,
- previous_name->len);
-
- *ent_size = (name - ((char *)ondisk)) + consumed;
- }
- return ce;
-}
-
-static int read_index_v2(struct index_state *istate, void *mmap, unsigned long mmap_size)
-{
- int i;
- unsigned long src_offset;
- struct cache_header *hdr;
- struct strbuf previous_name_buf = STRBUF_INIT, *previous_name;
-
- hdr = mmap;
-
- istate->version = ntohl(hdr->hdr_version);
- istate->cache_nr = ntohl(hdr->hdr_entries);
- istate->cache_alloc = alloc_nr(istate->cache_nr);
- istate->cache = xcalloc(istate->cache_alloc, sizeof(*istate->cache));
- istate->initialized = 1;
-
- if (istate->version == 4)
- previous_name = &previous_name_buf;
- else
- previous_name = NULL;
-
- src_offset = sizeof(*hdr);
- for (i = 0; i < istate->cache_nr; i++) {
- struct ondisk_cache_entry *disk_ce;
- struct cache_entry *ce;
- unsigned long consumed;
-
- disk_ce = (struct ondisk_cache_entry *)((char *)mmap + src_offset);
- ce = create_from_disk(disk_ce, &consumed, previous_name);
- set_index_entry(istate, i, ce);
-
- src_offset += consumed;
- }
- strbuf_release(&previous_name_buf);
-
- while (src_offset <= mmap_size - 20 - 8) {
- /* After an array of active_nr index entries,
- * there can be arbitrary number of extended
- * sections, each of which is prefixed with
- * extension name (4-byte) and section length
- * in 4-byte network byte order.
- */
- uint32_t extsize;
- memcpy(&extsize, (char *)mmap + src_offset + 4, 4);
- extsize = ntohl(extsize);
- if (read_index_extension(istate,
- (const char *) mmap + src_offset,
- (char *) mmap + src_offset + 8,
- extsize) < 0)
- goto unmap;
- src_offset += 8;
- src_offset += extsize;
- }
- return 0;
-unmap:
- munmap(mmap, mmap_size);
- die("index file corrupt");
-}
-
/* remember to discard_cache() before reading a different cache! */
int read_index_from(struct index_state *istate, const char *path)
{
@@ -1508,10 +1307,13 @@ int read_index_from(struct index_state *istate, const char *path)
errno = ENOENT;
istate->timestamp.sec = 0;
istate->timestamp.nsec = 0;
+
fd = open(path, O_RDONLY);
if (fd < 0) {
- if (errno == ENOENT)
+ if (errno == ENOENT) {
+ initialize_index(istate, 0);
return 0;
+ }
die_errno("index file open failed");
}
@@ -1520,24 +1322,23 @@ int read_index_from(struct index_state *istate, const char *path)
errno = EINVAL;
mmap_size = xsize_t(st.st_size);
- if (mmap_size < sizeof(struct cache_header) + 20)
- die("index file smaller than expected");
-
mmap = xmmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
close(fd);
if (mmap == MAP_FAILED)
die_errno("unable to map index file");
hdr = mmap;
- if (verify_hdr_version(hdr, mmap_size) < 0)
+ if (verify_hdr_version(istate, hdr, mmap_size) < 0)
goto unmap;
- if (verify_hdr(mmap, mmap_size) < 0)
+ if (istate->ops->verify_hdr(mmap, mmap_size) < 0)
goto unmap;
- read_index_v2(istate, mmap, mmap_size);
+ if (istate->ops->read_index(istate, mmap, mmap_size) < 0)
+ goto unmap;
istate->timestamp.sec = st.st_mtime;
istate->timestamp.nsec = ST_MTIME_NSEC(st);
+
munmap(mmap, mmap_size);
return istate->cache_nr;
@@ -1568,6 +1369,7 @@ int discard_index(struct index_state *istate)
free(istate->cache);
istate->cache = NULL;
istate->cache_alloc = 0;
+ istate->ops = NULL;
return 0;
}
@@ -1581,201 +1383,6 @@ int unmerged_index(const struct index_state *istate)
return 0;
}
-#define WRITE_BUFFER_SIZE 8192
-static unsigned char write_buffer[WRITE_BUFFER_SIZE];
-static unsigned long write_buffer_len;
-
-static int ce_write_flush(git_SHA_CTX *context, int fd)
-{
- unsigned int buffered = write_buffer_len;
- if (buffered) {
- git_SHA1_Update(context, write_buffer, buffered);
- if (write_in_full(fd, write_buffer, buffered) != buffered)
- return -1;
- write_buffer_len = 0;
- }
- return 0;
-}
-
-static int ce_write(git_SHA_CTX *context, int fd, void *data, unsigned int len)
-{
- while (len) {
- unsigned int buffered = write_buffer_len;
- unsigned int partial = WRITE_BUFFER_SIZE - buffered;
- if (partial > len)
- partial = len;
- memcpy(write_buffer + buffered, data, partial);
- buffered += partial;
- if (buffered == WRITE_BUFFER_SIZE) {
- write_buffer_len = buffered;
- if (ce_write_flush(context, fd))
- return -1;
- buffered = 0;
- }
- write_buffer_len = buffered;
- len -= partial;
- data = (char *) data + partial;
- }
- return 0;
-}
-
-static int write_index_ext_header(git_SHA_CTX *context, int fd,
- unsigned int ext, unsigned int sz)
-{
- ext = htonl(ext);
- sz = htonl(sz);
- return ((ce_write(context, fd, &ext, 4) < 0) ||
- (ce_write(context, fd, &sz, 4) < 0)) ? -1 : 0;
-}
-
-static int ce_flush(git_SHA_CTX *context, int fd)
-{
- unsigned int left = write_buffer_len;
-
- if (left) {
- write_buffer_len = 0;
- git_SHA1_Update(context, write_buffer, left);
- }
-
- /* Flush first if not enough space for SHA1 signature */
- if (left + 20 > WRITE_BUFFER_SIZE) {
- if (write_in_full(fd, write_buffer, left) != left)
- return -1;
- left = 0;
- }
-
- /* Append the SHA1 signature at the end */
- git_SHA1_Final(write_buffer + left, context);
- left += 20;
- return (write_in_full(fd, write_buffer, left) != left) ? -1 : 0;
-}
-
-static void ce_smudge_racily_clean_entry(struct cache_entry *ce)
-{
- /*
- * The only thing we care about in this function is to smudge the
- * falsely clean entry due to touch-update-touch race, so we leave
- * everything else as they are. We are called for entries whose
- * ce_stat_data.sd_mtime match the index file mtime.
- *
- * Note that this actually does not do much for gitlinks, for
- * which ce_match_stat_basic() always goes to the actual
- * contents. The caller checks with is_racy_timestamp() which
- * always says "no" for gitlinks, so we are not called for them ;-)
- */
- struct stat st;
-
- if (lstat(ce->name, &st) < 0)
- return;
- if (ce_match_stat_basic(ce, &st))
- return;
- if (ce_modified_check_fs(ce, &st)) {
- /* This is "racily clean"; smudge it. Note that this
- * is a tricky code. At first glance, it may appear
- * that it can break with this sequence:
- *
- * $ echo xyzzy >frotz
- * $ git-update-index --add frotz
- * $ : >frotz
- * $ sleep 3
- * $ echo filfre >nitfol
- * $ git-update-index --add nitfol
- *
- * but it does not. When the second update-index runs,
- * it notices that the entry "frotz" has the same timestamp
- * as index, and if we were to smudge it by resetting its
- * size to zero here, then the object name recorded
- * in index is the 6-byte file but the cached stat information
- * becomes zero --- which would then match what we would
- * obtain from the filesystem next time we stat("frotz").
- *
- * However, the second update-index, before calling
- * this function, notices that the cached size is 6
- * bytes and what is on the filesystem is an empty
- * file, and never calls us, so the cached size information
- * for "frotz" stays 6 which does not match the filesystem.
- */
- ce->ce_stat_data.sd_size = 0;
- }
-}
-
-/* Copy miscellaneous fields but not the name */
-static char *copy_cache_entry_to_ondisk(struct ondisk_cache_entry *ondisk,
- struct cache_entry *ce)
-{
- short flags;
-
- ondisk->ctime.sec = htonl(ce->ce_stat_data.sd_ctime.sec);
- ondisk->mtime.sec = htonl(ce->ce_stat_data.sd_mtime.sec);
- ondisk->ctime.nsec = htonl(ce->ce_stat_data.sd_ctime.nsec);
- ondisk->mtime.nsec = htonl(ce->ce_stat_data.sd_mtime.nsec);
- ondisk->dev = htonl(ce->ce_stat_data.sd_dev);
- ondisk->ino = htonl(ce->ce_stat_data.sd_ino);
- ondisk->mode = htonl(ce->ce_mode);
- ondisk->uid = htonl(ce->ce_stat_data.sd_uid);
- ondisk->gid = htonl(ce->ce_stat_data.sd_gid);
- ondisk->size = htonl(ce->ce_stat_data.sd_size);
- hashcpy(ondisk->sha1, ce->sha1);
-
- flags = ce->ce_flags;
- flags |= (ce_namelen(ce) >= CE_NAMEMASK ? CE_NAMEMASK : ce_namelen(ce));
- ondisk->flags = htons(flags);
- if (ce->ce_flags & CE_EXTENDED) {
- struct ondisk_cache_entry_extended *ondisk2;
- ondisk2 = (struct ondisk_cache_entry_extended *)ondisk;
- ondisk2->flags2 = htons((ce->ce_flags & CE_EXTENDED_FLAGS) >> 16);
- return ondisk2->name;
- }
- else {
- return ondisk->name;
- }
-}
-
-static int ce_write_entry(git_SHA_CTX *c, int fd, struct cache_entry *ce,
- struct strbuf *previous_name)
-{
- int size;
- struct ondisk_cache_entry *ondisk;
- char *name;
- int result;
-
- if (!previous_name) {
- size = ondisk_ce_size(ce);
- ondisk = xcalloc(1, size);
- name = copy_cache_entry_to_ondisk(ondisk, ce);
- memcpy(name, ce->name, ce_namelen(ce));
- } else {
- int common, to_remove, prefix_size;
- unsigned char to_remove_vi[16];
- for (common = 0;
- (ce->name[common] &&
- common < previous_name->len &&
- ce->name[common] == previous_name->buf[common]);
- common++)
- ; /* still matching */
- to_remove = previous_name->len - common;
- prefix_size = encode_varint(to_remove, to_remove_vi);
-
- if (ce->ce_flags & CE_EXTENDED)
- size = offsetof(struct ondisk_cache_entry_extended, name);
- else
- size = offsetof(struct ondisk_cache_entry, name);
- size += prefix_size + (ce_namelen(ce) - common + 1);
-
- ondisk = xcalloc(1, size);
- name = copy_cache_entry_to_ondisk(ondisk, ce);
- memcpy(name, to_remove_vi, prefix_size);
- memcpy(name + prefix_size, ce->name + common, ce_namelen(ce) - common);
-
- strbuf_splice(previous_name, common, to_remove,
- ce->name + common, ce_namelen(ce) - common);
- }
-
- result = ce_write(c, fd, ondisk, size);
- free(ondisk);
- return result;
-}
-
static int has_racy_timestamp(struct index_state *istate)
{
int entries = istate->cache_nr;
@@ -1801,101 +1408,9 @@ void update_index_if_able(struct index_state *istate, struct lock_file *lockfile
rollback_lock_file(lockfile);
}
-static int write_index_v2(struct index_state *istate, int newfd)
-{
- git_SHA_CTX c;
- struct cache_header hdr;
- int i, err, removed, extended, hdr_version;
- struct cache_entry **cache = istate->cache;
- int entries = istate->cache_nr;
- struct stat st;
- struct strbuf previous_name_buf = STRBUF_INIT, *previous_name;
-
- for (i = removed = extended = 0; i < entries; i++) {
- if (cache[i]->ce_flags & CE_REMOVE)
- removed++;
-
- /* reduce extended entries if possible */
- cache[i]->ce_flags &= ~CE_EXTENDED;
- if (cache[i]->ce_flags & CE_EXTENDED_FLAGS) {
- extended++;
- cache[i]->ce_flags |= CE_EXTENDED;
- }
- }
-
- if (!istate->version)
- istate->version = INDEX_FORMAT_DEFAULT;
-
- /* demote version 3 to version 2 when the latter suffices */
- if (istate->version == 3 || istate->version == 2)
- istate->version = extended ? 3 : 2;
-
- hdr_version = istate->version;
-
- hdr.hdr_signature = htonl(CACHE_SIGNATURE);
- hdr.hdr_version = htonl(hdr_version);
- hdr.hdr_entries = htonl(entries - removed);
-
- git_SHA1_Init(&c);
- if (ce_write(&c, newfd, &hdr, sizeof(hdr)) < 0)
- return -1;
-
- previous_name = (hdr_version == 4) ? &previous_name_buf : NULL;
- for (i = 0; i < entries; i++) {
- struct cache_entry *ce = cache[i];
- if (ce->ce_flags & CE_REMOVE)
- continue;
- if (!ce_uptodate(ce) && is_racy_timestamp(istate, ce))
- ce_smudge_racily_clean_entry(ce);
- if (is_null_sha1(ce->sha1)) {
- static const char msg[] = "cache entry has null sha1: %s";
- static int allow = -1;
-
- if (allow < 0)
- allow = git_env_bool("GIT_ALLOW_NULL_SHA1", 0);
- if (allow)
- warning(msg, ce->name);
- else
- return error(msg, ce->name);
- }
- if (ce_write_entry(&c, newfd, ce, previous_name) < 0)
- return -1;
- }
- strbuf_release(&previous_name_buf);
-
- /* Write extension data here */
- if (istate->cache_tree) {
- struct strbuf sb = STRBUF_INIT;
-
- cache_tree_write(&sb, istate->cache_tree);
- err = write_index_ext_header(&c, newfd, CACHE_EXT_TREE, sb.len) < 0
- || ce_write(&c, newfd, sb.buf, sb.len) < 0;
- strbuf_release(&sb);
- if (err)
- return -1;
- }
- if (istate->resolve_undo) {
- struct strbuf sb = STRBUF_INIT;
-
- resolve_undo_write(&sb, istate->resolve_undo);
- err = write_index_ext_header(&c, newfd, CACHE_EXT_RESOLVE_UNDO,
- sb.len) < 0
- || ce_write(&c, newfd, sb.buf, sb.len) < 0;
- strbuf_release(&sb);
- if (err)
- return -1;
- }
-
- if (ce_flush(&c, newfd) || fstat(newfd, &st))
- return -1;
- istate->timestamp.sec = (unsigned int)st.st_mtime;
- istate->timestamp.nsec = ST_MTIME_NSEC(st);
- return 0;
-}
-
int write_index(struct index_state *istate, int newfd)
{
- return write_index_v2(istate, newfd);
+ return istate->ops->write_index(istate, newfd);
}
/*
diff --git a/read-cache.h b/read-cache.h
new file mode 100644
index 0000000..ceedcae
--- /dev/null
+++ b/read-cache.h
@@ -0,0 +1,63 @@
+#ifndef READ_CACHE_H
+#define READ_CACHE_H
+
+/* Index extensions.
+ *
+ * The first letter should be 'A'..'Z' for extensions that are not
+ * necessary for a correct operation (i.e. optimization data).
+ * When new extensions are added that _needs_ to be understood in
+ * order to correctly interpret the index file, pick character that
+ * is outside the range, to cause the reader to abort.
+ */
+
+#define CACHE_EXT(s) ( (s[0]<<24)|(s[1]<<16)|(s[2]<<8)|(s[3]) )
+#define CACHE_EXT_TREE 0x54524545 /* "TREE" */
+#define CACHE_EXT_RESOLVE_UNDO 0x52455543 /* "REUC" */
+
+#define INDEX_FORMAT_DEFAULT 3
+
+/*
+ * Basic data structures for the directory cache
+ */
+struct cache_header {
+ uint32_t hdr_signature;
+ uint32_t hdr_version;
+ uint32_t hdr_entries;
+};
+
+struct index_ops {
+ int (*match_stat_basic)(const struct cache_entry *ce, struct stat *st, int changed);
+ int (*verify_hdr)(void *mmap, unsigned long size);
+ int (*read_index)(struct index_state *istate, void *mmap, unsigned long mmap_size);
+ int (*write_index)(struct index_state *istate, int newfd);
+};
+
+extern struct index_ops v2_ops;
+
+#ifndef NEEDS_ALIGNED_ACCESS
+#define ntoh_s(var) ntohs(var)
+#define ntoh_l(var) ntohl(var)
+#else
+static inline uint16_t ntoh_s_force_align(void *p)
+{
+ uint16_t x;
+ memcpy(&x, p, sizeof(x));
+ return ntohs(x);
+}
+static inline uint32_t ntoh_l_force_align(void *p)
+{
+ uint32_t x;
+ memcpy(&x, p, sizeof(x));
+ return ntohl(x);
+}
+#define ntoh_s(var) ntoh_s_force_align(&(var))
+#define ntoh_l(var) ntoh_l_force_align(&(var))
+#endif
+
+extern int ce_modified_check_fs(const struct cache_entry *ce, struct stat *st);
+extern int ce_match_stat_basic(const struct index_state *istate,
+ const struct cache_entry *ce, struct stat *st);
+extern int is_racy_timestamp(const struct index_state *istate, const struct cache_entry *ce);
+extern void set_index_entry(struct index_state *istate, int nr, struct cache_entry *ce);
+
+#endif
diff --git a/test-index-version.c b/test-index-version.c
index 05d4699..d3c0ebd 100644
--- a/test-index-version.c
+++ b/test-index-version.c
@@ -1,5 +1,11 @@
#include "cache.h"
+struct cache_header {
+ uint32_t hdr_signature;
+ uint32_t hdr_version;
+ uint32_t hdr_entries;
+};
+
int main(int argc, char **argv)
{
struct cache_header hdr;
diff --git a/unpack-trees.c b/unpack-trees.c
index 35cb05e..8d07c2a 100644
--- a/unpack-trees.c
+++ b/unpack-trees.c
@@ -1035,10 +1035,9 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options
}
memset(&o->result, 0, sizeof(o->result));
- o->result.initialized = 1;
+ initialize_index(&o->result, o->src_index->version);
o->result.timestamp.sec = o->src_index->timestamp.sec;
o->result.timestamp.nsec = o->src_index->timestamp.nsec;
- o->result.version = o->src_index->version;
o->merge_size = len;
mark_all_ce_unused(o->src_index);
--
1.8.4.2
--
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