diff options
| -rw-r--r-- | builtin-pack-objects.c | 3 | ||||
| -rw-r--r-- | fast-import.c | 3 | ||||
| -rw-r--r-- | index-pack.c | 3 | ||||
| -rw-r--r-- | pack-write.c | 71 | ||||
| -rw-r--r-- | pack.h | 2 |
5 files changed, 66 insertions, 16 deletions
diff --git a/builtin-pack-objects.c b/builtin-pack-objects.c index 640e05a12..501f9367c 100644 --- a/builtin-pack-objects.c +++ b/builtin-pack-objects.c @@ -493,7 +493,8 @@ static void write_pack_file(void) sha1close(f, sha1, CSUM_FSYNC); } else { int fd = sha1close(f, NULL, 0); - fixup_pack_header_footer(fd, sha1, pack_tmp_name, nr_written); + fixup_pack_header_footer(fd, sha1, pack_tmp_name, + nr_written, NULL, 0); close(fd); } diff --git a/fast-import.c b/fast-import.c index 7089e6f9e..d85b3a561 100644 --- a/fast-import.c +++ b/fast-import.c @@ -951,7 +951,8 @@ static void end_packfile(void) close_pack_windows(pack_data); fixup_pack_header_footer(pack_data->pack_fd, pack_data->sha1, - pack_data->pack_name, object_count); + pack_data->pack_name, object_count, + NULL, 0); close(pack_data->pack_fd); idx_name = keep_pack(create_index()); diff --git a/index-pack.c b/index-pack.c index 728af7da9..411b80d81 100644 --- a/index-pack.c +++ b/index-pack.c @@ -982,7 +982,8 @@ int main(int argc, char **argv) nr_objects - nr_objects_initial); stop_progress_msg(&progress, msg); fixup_pack_header_footer(output_fd, sha1, - curr_pack, nr_objects); + curr_pack, nr_objects, + NULL, 0); } if (nr_deltas != nr_resolved_deltas) die("pack has %d unresolved deltas", diff --git a/pack-write.c b/pack-write.c index ddcfd37af..f9776c51f 100644 --- a/pack-write.c +++ b/pack-write.c @@ -144,41 +144,88 @@ char *write_idx_file(char *index_name, struct pack_idx_entry **objects, return index_name; } +/* + * Update pack header with object_count and compute new SHA1 for pack data + * associated to pack_fd, and write that SHA1 at the end. That new SHA1 + * is also returned in new_pack_sha1. + * + * If partial_pack_sha1 is non null, then the SHA1 of the existing pack + * (without the header update) is computed and validated against the + * one provided in partial_pack_sha1. The validation is performed at + * partial_pack_offset bytes in the pack file. The SHA1 of the remaining + * data (i.e. from partial_pack_offset to the end) is then computed and + * returned in partial_pack_sha1. + * + * Note that new_pack_sha1 is updated last, so both new_pack_sha1 and + * partial_pack_sha1 can refer to the same buffer if the caller is not + * interested in the resulting SHA1 of pack data above partial_pack_offset. + */ void fixup_pack_header_footer(int pack_fd, - unsigned char *pack_file_sha1, + unsigned char *new_pack_sha1, const char *pack_name, - uint32_t object_count) + uint32_t object_count, + unsigned char *partial_pack_sha1, + off_t partial_pack_offset) { static const int buf_sz = 128 * 1024; - SHA_CTX c; + SHA_CTX old_sha1_ctx, new_sha1_ctx; struct pack_header hdr; char *buf; + SHA1_Init(&old_sha1_ctx); + SHA1_Init(&new_sha1_ctx); + if (lseek(pack_fd, 0, SEEK_SET) != 0) - die("Failed seeking to start: %s", strerror(errno)); + die("Failed seeking to start of %s: %s", pack_name, strerror(errno)); if (read_in_full(pack_fd, &hdr, sizeof(hdr)) != sizeof(hdr)) die("Unable to reread header of %s: %s", pack_name, strerror(errno)); if (lseek(pack_fd, 0, SEEK_SET) != 0) - die("Failed seeking to start: %s", strerror(errno)); + die("Failed seeking to start of %s: %s", pack_name, strerror(errno)); + SHA1_Update(&old_sha1_ctx, &hdr, sizeof(hdr)); hdr.hdr_entries = htonl(object_count); + SHA1_Update(&new_sha1_ctx, &hdr, sizeof(hdr)); write_or_die(pack_fd, &hdr, sizeof(hdr)); - - SHA1_Init(&c); - SHA1_Update(&c, &hdr, sizeof(hdr)); + partial_pack_offset -= sizeof(hdr); buf = xmalloc(buf_sz); for (;;) { - ssize_t n = xread(pack_fd, buf, buf_sz); + ssize_t m, n; + m = (partial_pack_sha1 && partial_pack_offset < buf_sz) ? + partial_pack_offset : buf_sz; + n = xread(pack_fd, buf, m); if (!n) break; if (n < 0) die("Failed to checksum %s: %s", pack_name, strerror(errno)); - SHA1_Update(&c, buf, n); + SHA1_Update(&new_sha1_ctx, buf, n); + + if (!partial_pack_sha1) + continue; + + SHA1_Update(&old_sha1_ctx, buf, n); + partial_pack_offset -= n; + if (partial_pack_offset == 0) { + unsigned char sha1[20]; + SHA1_Final(sha1, &old_sha1_ctx); + if (hashcmp(sha1, partial_pack_sha1) != 0) + die("Unexpected checksum for %s " + "(disk corruption?)", pack_name); + /* + * Now let's compute the SHA1 of the remainder of the + * pack, which also means making partial_pack_offset + * big enough not to matter anymore. + */ + SHA1_Init(&old_sha1_ctx); + partial_pack_offset = ~partial_pack_offset; + partial_pack_offset -= MSB(partial_pack_offset, 1); + } } free(buf); - SHA1_Final(pack_file_sha1, &c); - write_or_die(pack_fd, pack_file_sha1, 20); + if (partial_pack_sha1) + SHA1_Final(partial_pack_sha1, &old_sha1_ctx); + SHA1_Final(new_pack_sha1, &new_sha1_ctx); + write_or_die(pack_fd, new_pack_sha1, 20); fsync_or_die(pack_fd, pack_name); } @@ -58,7 +58,7 @@ struct pack_idx_entry { extern char *write_idx_file(char *index_name, struct pack_idx_entry **objects, int nr_objects, unsigned char *sha1); extern int check_pack_crc(struct packed_git *p, struct pack_window **w_curs, off_t offset, off_t len, unsigned int nr); extern int verify_pack(struct packed_git *); -extern void fixup_pack_header_footer(int, unsigned char *, const char *, uint32_t); +extern void fixup_pack_header_footer(int, unsigned char *, const char *, uint32_t, unsigned char *, off_t); extern char *index_pack_lockfile(int fd); #define PH_ERROR_EOF (-1) |