diff options
Diffstat (limited to 'sha1_file.c')
| -rw-r--r-- | sha1_file.c | 114 |
1 files changed, 78 insertions, 36 deletions
diff --git a/sha1_file.c b/sha1_file.c index 287f61882..baaa4c00d 100644 --- a/sha1_file.c +++ b/sha1_file.c @@ -1248,6 +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; @@ -1257,7 +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. @@ -1320,32 +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) @@ -1420,8 +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]; @@ -1429,10 +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)); @@ -1462,7 +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"); @@ -1475,15 +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) |