X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=sha1_file.c;h=baaa4c00da50342a7db8064dadf7f963b0e2e679;hb=11f0dafe2be419240c0006c3e9112cbad3568baf;hp=776697755a02b98c04fa7831077bd0205a1feb80;hpb=9577e7e3db2299febdc17539478bba38874d4120;p=git.git diff --git a/sha1_file.c b/sha1_file.c index 77669775..baaa4c00 100644 --- a/sha1_file.c +++ b/sha1_file.c @@ -20,6 +20,8 @@ #endif #endif +const unsigned char null_sha1[20] = { 0, }; + static unsigned int sha1_file_open_flag = O_NOATIME; static unsigned hexval(char c) @@ -50,26 +52,33 @@ static char *git_dir, *git_object_dir, *git_index_file, *git_refs_dir, *git_graft_file; static void setup_git_env(void) { - git_dir = gitenv(GIT_DIR_ENVIRONMENT); + git_dir = getenv(GIT_DIR_ENVIRONMENT); if (!git_dir) git_dir = DEFAULT_GIT_DIR_ENVIRONMENT; - git_object_dir = gitenv(DB_ENVIRONMENT); + git_object_dir = getenv(DB_ENVIRONMENT); if (!git_object_dir) { git_object_dir = xmalloc(strlen(git_dir) + 9); sprintf(git_object_dir, "%s/objects", git_dir); } git_refs_dir = xmalloc(strlen(git_dir) + 6); sprintf(git_refs_dir, "%s/refs", git_dir); - git_index_file = gitenv(INDEX_ENVIRONMENT); + git_index_file = getenv(INDEX_ENVIRONMENT); if (!git_index_file) { git_index_file = xmalloc(strlen(git_dir) + 7); sprintf(git_index_file, "%s/index", git_dir); } - git_graft_file = gitenv(GRAFT_ENVIRONMENT); + git_graft_file = getenv(GRAFT_ENVIRONMENT); if (!git_graft_file) git_graft_file = strdup(git_path("info/grafts")); } +char *get_git_dir(void) +{ + if (!git_dir) + setup_git_env(); + return git_dir; +} + char *get_object_directory(void) { if (!git_object_dir) @@ -240,10 +249,12 @@ static struct alternate_object_database **alt_odb_tail; * SHA1, an extra slash for the first level indirection, and the * terminating NUL. */ -static void link_alt_odb_entries(const char *alt, const char *ep, int sep) +static void link_alt_odb_entries(const char *alt, const char *ep, int sep, + const char *relative_base) { const char *cp, *last; struct alternate_object_database *ent; + int base_len = -1; last = alt; while (last < ep) { @@ -261,12 +272,25 @@ static void link_alt_odb_entries(const char *alt, const char *ep, int sep) int pfxlen = cp - last; int entlen = pfxlen + 43; + if (*last != '/' && relative_base) { + /* Relative alt-odb */ + if (base_len < 0) + base_len = strlen(relative_base) + 1; + entlen += base_len; + pfxlen += base_len; + } ent = xmalloc(sizeof(*ent) + entlen); *alt_odb_tail = ent; alt_odb_tail = &(ent->next); ent->next = NULL; - - memcpy(ent->base, last, pfxlen); + if (*last != '/' && relative_base) { + memcpy(ent->base, relative_base, base_len - 1); + ent->base[base_len - 1] = '/'; + memcpy(ent->base + base_len, + last, cp - last); + } + else + memcpy(ent->base, last, pfxlen); ent->name = ent->base + pfxlen + 1; ent->base[pfxlen] = ent->base[pfxlen + 3] = '/'; ent->base[entlen-1] = 0; @@ -283,14 +307,17 @@ void prepare_alt_odb(void) char *map; int fd; struct stat st; - char *alt = gitenv(ALTERNATE_DB_ENVIRONMENT) ? : ""; + char *alt; + + alt = getenv(ALTERNATE_DB_ENVIRONMENT); + if (!alt) alt = ""; - sprintf(path, "%s/info/alternates", get_object_directory()); if (alt_odb_tail) return; alt_odb_tail = &alt_odb_list; - link_alt_odb_entries(alt, alt + strlen(alt), ':'); + link_alt_odb_entries(alt, alt + strlen(alt), ':', NULL); + sprintf(path, "%s/info/alternates", get_object_directory()); fd = open(path, O_RDONLY); if (fd < 0) return; @@ -303,7 +330,8 @@ void prepare_alt_odb(void) if (map == MAP_FAILED) return; - link_alt_odb_entries(map, map + st.st_size, '\n'); + link_alt_odb_entries(map, map + st.st_size, '\n', + get_object_directory()); munmap(map, st.st_size); } @@ -484,7 +512,7 @@ struct packed_git *parse_pack_index(unsigned char *sha1) return parse_pack_index_file(sha1, path); } -struct packed_git *parse_pack_index_file(unsigned char *sha1, char *idx_path) +struct packed_git *parse_pack_index_file(const unsigned char *sha1, char *idx_path) { struct packed_git *p; unsigned long idx_size; @@ -845,7 +873,8 @@ void packed_object_info_detail(struct pack_entry *e, strcpy(type, "tag"); break; default: - die("corrupted pack file"); + die("corrupted pack file %s containing object of kind %d", + p->pack_name, kind); } *store_size = 0; /* notyet */ } @@ -884,7 +913,8 @@ static int packed_object_info(struct pack_entry *entry, strcpy(type, "tag"); break; default: - die("corrupted pack file"); + die("corrupted pack file %s containing object of kind %d", + p->pack_name, kind); } if (sizep) *sizep = size; @@ -984,7 +1014,7 @@ static void *unpack_entry(struct pack_entry *entry, retval = unpack_entry_gently(entry, type, sizep); unuse_packed_git(p); if (!retval) - die("corrupted pack file"); + die("corrupted pack file %s", p->pack_name); return retval; } @@ -1218,6 +1248,73 @@ char *write_sha1_file_prepare(void *buf, return sha1_file_name(sha1); } +/* + * Link the tempfile to the final place, possibly creating the + * last directory level as you do so. + * + * Returns the errno on failure, 0 on success. + */ +static int link_temp_to_file(const char *tmpfile, char *filename) +{ + int ret; + + if (!link(tmpfile, filename)) + return 0; + + /* + * Try to mkdir the last path component if that failed + * with an ENOENT. + * + * Re-try the "link()" regardless of whether the mkdir + * succeeds, since a race might mean that somebody + * else succeeded. + */ + ret = errno; + if (ret == ENOENT) { + char *dir = strrchr(filename, '/'); + if (dir) { + *dir = 0; + mkdir(filename, 0777); + *dir = '/'; + if (!link(tmpfile, filename)) + return 0; + ret = errno; + } + } + return ret; +} + +/* + * Move the just written object into its final resting place + */ +static int move_temp_to_file(const char *tmpfile, char *filename) +{ + int ret = link_temp_to_file(tmpfile, filename); + if (ret) { + /* + * Coda hack - coda doesn't like cross-directory links, + * so we fall back to a rename, which will mean that it + * won't be able to check collisions, but that's not a + * big deal. + * + * When this succeeds, we just return 0. We have nothing + * left to unlink. + */ + if (ret == EXDEV && !rename(tmpfile, filename)) + return 0; + } + unlink(tmpfile); + if (ret) { + if (ret != EEXIST) { + fprintf(stderr, "unable to write sha1 filename %s: %s", filename, strerror(ret)); + return -1; + } + /* FIXME!!! Collision check here ? */ + } + + return 0; +} + int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *returnsha1) { int size; @@ -1227,7 +1324,7 @@ int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned cha char *filename; static char tmpfile[PATH_MAX]; unsigned char hdr[50]; - int fd, hdrlen, ret; + int fd, hdrlen; /* Normally if we have it in the pack then we do not bother writing * it out into .git/objects/??/?{38} file. @@ -1290,32 +1387,7 @@ int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned cha close(fd); free(compressed); - ret = link(tmpfile, filename); - if (ret < 0) { - ret = errno; - - /* - * Coda hack - coda doesn't like cross-directory links, - * so we fall back to a rename, which will mean that it - * won't be able to check collisions, but that's not a - * big deal. - * - * When this succeeds, we just return 0. We have nothing - * left to unlink. - */ - if (ret == EXDEV && !rename(tmpfile, filename)) - return 0; - } - unlink(tmpfile); - if (ret) { - if (ret != EEXIST) { - fprintf(stderr, "unable to write sha1 filename %s: %s", filename, strerror(ret)); - return -1; - } - /* FIXME!!! Collision check here ? */ - } - - return 0; + return move_temp_to_file(tmpfile, filename); } int write_sha1_to_fd(int fd, const unsigned char *sha1) @@ -1390,8 +1462,7 @@ int write_sha1_to_fd(int fd, const unsigned char *sha1) int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer, size_t bufsize, size_t *bufposn) { - char *filename = sha1_file_name(sha1); - + char tmpfile[PATH_MAX]; int local; z_stream stream; unsigned char real_sha1[20]; @@ -1399,10 +1470,11 @@ int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer, int ret; SHA_CTX c; - local = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0666); + snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory()); + local = mkstemp(tmpfile); if (local < 0) - return error("Couldn't open %s\n", filename); + return error("Couldn't open %s for %s\n", tmpfile, sha1_to_hex(sha1)); memset(&stream, 0, sizeof(stream)); @@ -1432,7 +1504,7 @@ int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer, size = read(fd, buffer + *bufposn, bufsize - *bufposn); if (size <= 0) { close(local); - unlink(filename); + unlink(tmpfile); if (!size) return error("Connection closed?"); perror("Reading from connection"); @@ -1445,15 +1517,15 @@ int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer, close(local); SHA1_Final(real_sha1, &c); if (ret != Z_STREAM_END) { - unlink(filename); + unlink(tmpfile); return error("File %s corrupted", sha1_to_hex(sha1)); } if (memcmp(sha1, real_sha1, 20)) { - unlink(filename); + unlink(tmpfile); return error("File %s has bad hash\n", sha1_to_hex(sha1)); } - - return 0; + + return move_temp_to_file(tmpfile, sha1_file_name(sha1)); } int has_pack_index(const unsigned char *sha1) @@ -1515,3 +1587,42 @@ int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, con munmap(buf, size); return ret; } + +int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object) +{ + int fd; + char *target; + + switch (st->st_mode & S_IFMT) { + case S_IFREG: + fd = open(path, O_RDONLY); + if (fd < 0) + return error("open(\"%s\"): %s", path, + strerror(errno)); + if (index_fd(sha1, fd, st, write_object, NULL) < 0) + return error("%s: failed to insert into database", + path); + break; + case S_IFLNK: + target = xmalloc(st->st_size+1); + if (readlink(path, target, st->st_size+1) != st->st_size) { + char *errstr = strerror(errno); + free(target); + return error("readlink(\"%s\"): %s", path, + errstr); + } + if (!write_object) { + unsigned char hdr[50]; + int hdrlen; + write_sha1_file_prepare(target, st->st_size, "blob", + sha1, hdr, &hdrlen); + } else if (write_sha1_file(target, st->st_size, "blob", sha1)) + return error("%s: failed to insert into database", + path); + free(target); + break; + default: + return error("%s: unsupported file type", path); + } + return 0; +}