This adds support for the script command mode where an helper script or command is called to retrieve or manage objects. This implements the 'have' and 'get_git_obj' instructions for the script mode. Signed-off-by: Christian Couder <chriscool@xxxxxxxxxxxxx> --- external-odb.c | 55 +++++++++- external-odb.h | 1 + odb-helper.c | 218 +++++++++++++++++++++++++++++++++++++++- odb-helper.h | 4 + sha1_file.c | 12 ++- t/t0500-external-odb.sh | 44 ++++++++ 6 files changed, 331 insertions(+), 3 deletions(-) create mode 100755 t/t0500-external-odb.sh diff --git a/external-odb.c b/external-odb.c index 82ac80aa04..ec1ec82dd9 100644 --- a/external-odb.c +++ b/external-odb.c @@ -33,8 +33,14 @@ static int external_odb_config(const char *var, const char *value, void *data) o = find_or_create_helper(name, namelen); - if (!strcmp(subkey, "promisorremote")) + if (!strcmp(subkey, "promisorremote")) { + o->type = ODB_HELPER_GIT_REMOTE; return git_config_string(&o->dealer, var, value); + } + if (!strcmp(subkey, "scriptcommand")) { + o->type = ODB_HELPER_SCRIPT_CMD; + return git_config_string(&o->dealer, var, value); + } return 0; } @@ -100,6 +106,53 @@ int external_odb_has_object(const unsigned char *sha1) return 0; } +int external_odb_get_object(const unsigned char *sha1) +{ + struct odb_helper *o; + struct strbuf pathbuf = STRBUF_INIT; + + if (!external_odb_has_object(sha1)) + return -1; + + sha1_file_name_alt(&pathbuf, external_odb_root(), sha1); + safe_create_leading_directories_const(pathbuf.buf); + prepare_external_alt_odb(); + + for (o = helpers; o; o = o->next) { + struct strbuf tmpfile = STRBUF_INIT; + int ret; + int fd; + + if (!odb_helper_has_object(o, sha1)) + continue; + + fd = create_object_tmpfile(&tmpfile, pathbuf.buf); + if (fd < 0) { + strbuf_release(&tmpfile); + strbuf_release(&pathbuf); + return -1; + } + + if (odb_helper_get_object(o, sha1, fd) < 0) { + close(fd); + unlink(tmpfile.buf); + strbuf_release(&tmpfile); + continue; + } + + close_sha1_file(fd); + ret = finalize_object_file(tmpfile.buf, pathbuf.buf); + strbuf_release(&tmpfile); + strbuf_release(&pathbuf); + if (!ret) + return 0; + } + + strbuf_release(&pathbuf); + + return -1; +} + int external_odb_get_direct(const unsigned char *sha1) { struct odb_helper *o; diff --git a/external-odb.h b/external-odb.h index 254070994a..c5ac071995 100644 --- a/external-odb.h +++ b/external-odb.h @@ -15,6 +15,7 @@ extern struct odb_helper *find_odb_helper(const char *dealer, enum odb_helper_type type); extern const char *external_odb_root(void); extern int external_odb_has_object(const unsigned char *sha1); +extern int external_odb_get_object(const unsigned char *sha1); extern int external_odb_get_direct(const unsigned char *sha1); #endif /* EXTERNAL_ODB_H */ diff --git a/odb-helper.c b/odb-helper.c index c6127ce81f..677ea850a5 100644 --- a/odb-helper.c +++ b/odb-helper.c @@ -21,13 +21,124 @@ struct odb_helper_cmd { struct child_process child; }; +/* + * Callers are responsible to ensure that the result of vaddf(fmt, ap) + * is properly shell-quoted. + */ +static void prepare_helper_command(struct argv_array *argv, const char *cmd, + const char *fmt, va_list ap) +{ + struct strbuf buf = STRBUF_INIT; + + strbuf_addstr(&buf, cmd); + strbuf_addch(&buf, ' '); + strbuf_vaddf(&buf, fmt, ap); + + argv_array_push(argv, buf.buf); + strbuf_release(&buf); +} + +__attribute__((format (printf,3,4))) +static int odb_helper_start(struct odb_helper *o, + struct odb_helper_cmd *cmd, + const char *fmt, ...) +{ + va_list ap; + + memset(cmd, 0, sizeof(*cmd)); + argv_array_init(&cmd->argv); + + if (!o->dealer) + return -1; + + va_start(ap, fmt); + prepare_helper_command(&cmd->argv, o->dealer, fmt, ap); + va_end(ap); + + cmd->child.argv = cmd->argv.argv; + cmd->child.use_shell = 1; + cmd->child.no_stdin = 1; + cmd->child.out = -1; + + if (start_command(&cmd->child) < 0) { + argv_array_clear(&cmd->argv); + return -1; + } + + return 0; +} + +static int odb_helper_finish(struct odb_helper *o, + struct odb_helper_cmd *cmd) +{ + int ret = finish_command(&cmd->child); + argv_array_clear(&cmd->argv); + if (ret) { + warning("odb helper '%s' reported failure", o->name); + return -1; + } + return 0; +} + +static int parse_object_line(struct odb_helper_object *o, const char *line) +{ + char *end; + if (get_oid_hex(line, &o->oid) < 0) + return -1; + + line += 40; + if (*line++ != ' ') + return -1; + + o->size = strtoul(line, &end, 10); + if (line == end || *end++ != ' ') + return -1; + + o->type = type_from_string(end); + return 0; +} + +static int add_have_entry(struct odb_helper *o, const char *line) +{ + ALLOC_GROW(o->have, o->have_nr+1, o->have_alloc); + if (parse_object_line(&o->have[o->have_nr], line) < 0) { + warning("bad 'have' input from odb helper '%s': %s", + o->name, line); + return 1; + } + o->have_nr++; + return 0; +} + +static int odb_helper_object_cmp(const void *va, const void *vb) +{ + const struct odb_helper_object *a = va, *b = vb; + return oidcmp(&a->oid, &b->oid); +} + static void odb_helper_load_have(struct odb_helper *o) { + struct odb_helper_cmd cmd; + FILE *fh; + struct strbuf line = STRBUF_INIT; + if (o->have_valid) return; o->have_valid = 1; - /* TODO */ + if (odb_helper_start(o, &cmd, "have") < 0) + return; + + fh = xfdopen(cmd.child.out, "r"); + while (strbuf_getline(&line, fh) != EOF) + if (add_have_entry(o, line.buf)) + break; + + strbuf_release(&line); + fclose(fh); + odb_helper_finish(o, &cmd); + + qsort(o->have, o->have_nr, sizeof(*o->have), odb_helper_object_cmp); } static const unsigned char *have_sha1_access(size_t index, void *table) @@ -53,6 +164,111 @@ int odb_helper_has_object(struct odb_helper *o, const unsigned char *sha1) return !!odb_helper_lookup(o, sha1); } +int odb_helper_get_object(struct odb_helper *o, const unsigned char *sha1, + int fd) +{ + struct odb_helper_object *obj; + struct odb_helper_cmd cmd; + unsigned long total_got; + git_zstream stream; + int zret = Z_STREAM_END; + git_SHA_CTX hash; + unsigned char real_sha1[20]; + struct strbuf header = STRBUF_INIT; + unsigned long hdr_size; + + obj = odb_helper_lookup(o, sha1); + if (!obj) + return -1; + + if (odb_helper_start(o, &cmd, "get_git_obj %s", sha1_to_hex(sha1)) < 0) + return -1; + + memset(&stream, 0, sizeof(stream)); + git_inflate_init(&stream); + git_SHA1_Init(&hash); + total_got = 0; + + for (;;) { + unsigned char buf[4096]; + int r; + + r = xread(cmd.child.out, buf, sizeof(buf)); + if (r < 0) { + error("unable to read from odb helper '%s': %s", + o->name, strerror(errno)); + close(cmd.child.out); + odb_helper_finish(o, &cmd); + git_inflate_end(&stream); + return -1; + } + if (r == 0) + break; + + write_or_die(fd, buf, r); + + stream.next_in = buf; + stream.avail_in = r; + do { + unsigned char inflated[4096]; + unsigned long got; + + stream.next_out = inflated; + stream.avail_out = sizeof(inflated); + zret = git_inflate(&stream, Z_SYNC_FLUSH); + got = sizeof(inflated) - stream.avail_out; + + git_SHA1_Update(&hash, inflated, got); + /* skip header when counting size */ + if (!total_got) { + const unsigned char *p = memchr(inflated, '\0', got); + if (p) { + unsigned long hdr_last = p - inflated + 1; + strbuf_add(&header, inflated, hdr_last); + got -= hdr_last; + } else { + strbuf_add(&header, inflated, got); + got = 0; + } + } + total_got += got; + } while (stream.avail_in && zret == Z_OK); + } + + close(cmd.child.out); + git_inflate_end(&stream); + git_SHA1_Final(real_sha1, &hash); + if (odb_helper_finish(o, &cmd)) + return -1; + if (zret != Z_STREAM_END) { + warning("bad zlib data from odb helper '%s' for %s", + o->name, sha1_to_hex(sha1)); + return -1; + } + if (total_got != obj->size) { + warning("size mismatch from odb helper '%s' for %s (%lu != %lu)", + o->name, sha1_to_hex(sha1), total_got, obj->size); + return -1; + } + if (hashcmp(real_sha1, sha1)) { + warning("sha1 mismatch from odb helper '%s' for %s (got %s)", + o->name, sha1_to_hex(sha1), sha1_to_hex(real_sha1)); + return -1; + } + if (parse_sha1_header(header.buf, &hdr_size) < 0) { + warning("could not parse header from odb helper '%s' for %s", + o->name, sha1_to_hex(sha1)); + return -1; + } + if (total_got != hdr_size) { + warning("size mismatch from odb helper '%s' for %s (%lu != %lu)", + o->name, sha1_to_hex(sha1), total_got, hdr_size); + return -1; + } + + return 0; +} + int odb_helper_get_direct(struct odb_helper *o, const unsigned char *sha1) { diff --git a/odb-helper.h b/odb-helper.h index d4b968693f..819182f76a 100644 --- a/odb-helper.h +++ b/odb-helper.h @@ -23,6 +23,10 @@ struct odb_helper { extern struct odb_helper *odb_helper_new(const char *name, int namelen); extern int odb_helper_has_object(struct odb_helper *o, const unsigned char *sha1); +extern int odb_helper_get_object(struct odb_helper *o, + const unsigned char *sha1, + int fd); extern int odb_helper_get_direct(struct odb_helper *o, const unsigned char *sha1); + #endif /* ODB_HELPER_H */ diff --git a/sha1_file.c b/sha1_file.c index c460eb2658..847883f261 100644 --- a/sha1_file.c +++ b/sha1_file.c @@ -907,6 +907,9 @@ static int stat_sha1_file(const unsigned char *sha1, struct stat *st, return 0; } + if (!external_odb_get_object(sha1) && !lstat(*path, st)) + return 0; + return -1; } @@ -946,7 +949,14 @@ static int open_sha1_file(const unsigned char *sha1, const char **path) if (fd >= 0) return fd; - return open_sha1_file_alt(sha1, path); + fd = open_sha1_file_alt(sha1, path); + if (fd >= 0) + return fd; + + if (!external_odb_get_object(sha1)) + fd = open_sha1_file_alt(sha1, path); + + return fd; } /* diff --git a/t/t0500-external-odb.sh b/t/t0500-external-odb.sh new file mode 100755 index 0000000000..eaa3688a31 --- /dev/null +++ b/t/t0500-external-odb.sh @@ -0,0 +1,44 @@ +#!/bin/sh + +test_description='basic tests for external object databases' + +. ./test-lib.sh + +ALT_SOURCE="$PWD/alt-repo/.git" +export ALT_SOURCE +write_script odb-helper <<\EOF +GIT_DIR=$ALT_SOURCE; export GIT_DIR +case "$1" in +have) + git cat-file --batch-check --batch-all-objects | + awk '{print $1 " " $3 " " $2}' + ;; +get_git_obj) + cat "$GIT_DIR"/objects/$(echo $2 | sed 's#..#&/#') + ;; +esac +EOF +HELPER="\"$PWD\"/odb-helper" + +test_expect_success 'setup alternate repo' ' + git init alt-repo && + test_commit -C alt-repo one && + test_commit -C alt-repo two && + alt_head=$(git -C alt-repo rev-parse HEAD) +' + +test_expect_success 'alt objects are missing' ' + test_must_fail git log --format=%s $alt_head +' + +test_expect_success 'helper can retrieve alt objects' ' + test_config odb.magic.scriptCommand "$HELPER" && + cat >expect <<-\EOF && + two + one + EOF + git log --format=%s $alt_head >actual && + test_cmp expect actual +' + +test_done -- 2.17.0.rc0.37.g8f476fabe9