in src/indexer.c [1094:1293]
int git_indexer_commit(git_indexer *idx, git_indexer_progress *stats)
{
git_mwindow *w = NULL;
unsigned int i, long_offsets = 0, left;
int error;
struct git_pack_idx_header hdr;
git_buf filename = GIT_BUF_INIT;
struct entry *entry;
git_oid trailer_hash, file_hash;
git_filebuf index_file = {0};
void *packfile_trailer;
if (!idx->parsed_header) {
git_error_set(GIT_ERROR_INDEXER, "incomplete pack header");
return -1;
}
/* Test for this before resolve_deltas(), as it plays with idx->off */
if (idx->off + 20 < idx->pack->mwf.size) {
git_error_set(GIT_ERROR_INDEXER, "unexpected data at the end of the pack");
return -1;
}
if (idx->off + 20 > idx->pack->mwf.size) {
git_error_set(GIT_ERROR_INDEXER, "missing trailer at the end of the pack");
return -1;
}
packfile_trailer = git_mwindow_open(&idx->pack->mwf, &w, idx->pack->mwf.size - GIT_OID_RAWSZ, GIT_OID_RAWSZ, &left);
if (packfile_trailer == NULL) {
git_mwindow_close(&w);
goto on_error;
}
/* Compare the packfile trailer as it was sent to us and what we calculated */
git_oid_fromraw(&file_hash, packfile_trailer);
git_mwindow_close(&w);
git_hash_final(&trailer_hash, &idx->trailer);
if (git_oid_cmp(&file_hash, &trailer_hash)) {
git_error_set(GIT_ERROR_INDEXER, "packfile trailer mismatch");
return -1;
}
/* Freeze the number of deltas */
stats->total_deltas = stats->total_objects - stats->indexed_objects;
if ((error = resolve_deltas(idx, stats)) < 0)
return error;
if (stats->indexed_objects != stats->total_objects) {
git_error_set(GIT_ERROR_INDEXER, "early EOF");
return -1;
}
if (stats->local_objects > 0) {
if (update_header_and_rehash(idx, stats) < 0)
return -1;
git_hash_final(&trailer_hash, &idx->trailer);
write_at(idx, &trailer_hash, idx->pack->mwf.size - GIT_OID_RAWSZ, GIT_OID_RAWSZ);
}
/*
* Is the resulting graph fully connected or are we still
* missing some objects? In the second case, we can
* bail out due to an incomplete and thus corrupt
* packfile.
*/
if (git_oidmap_size(idx->expected_oids) > 0) {
git_error_set(GIT_ERROR_INDEXER, "packfile is missing %"PRIuZ" objects",
git_oidmap_size(idx->expected_oids));
return -1;
}
git_vector_sort(&idx->objects);
/* Use the trailer hash as the pack file name to ensure
* files with different contents have different names */
git_oid_cpy(&idx->hash, &trailer_hash);
git_buf_sets(&filename, idx->pack->pack_name);
git_buf_shorten(&filename, strlen("pack"));
git_buf_puts(&filename, "idx");
if (git_buf_oom(&filename))
return -1;
if (git_filebuf_open(&index_file, filename.ptr,
GIT_FILEBUF_HASH_CONTENTS |
(idx->do_fsync ? GIT_FILEBUF_FSYNC : 0),
idx->mode) < 0)
goto on_error;
/* Write out the header */
hdr.idx_signature = htonl(PACK_IDX_SIGNATURE);
hdr.idx_version = htonl(2);
git_filebuf_write(&index_file, &hdr, sizeof(hdr));
/* Write out the fanout table */
for (i = 0; i < 256; ++i) {
uint32_t n = htonl(idx->fanout[i]);
git_filebuf_write(&index_file, &n, sizeof(n));
}
/* Write out the object names (SHA-1 hashes) */
git_vector_foreach(&idx->objects, i, entry) {
git_filebuf_write(&index_file, &entry->oid, sizeof(git_oid));
}
/* Write out the CRC32 values */
git_vector_foreach(&idx->objects, i, entry) {
git_filebuf_write(&index_file, &entry->crc, sizeof(uint32_t));
}
/* Write out the offsets */
git_vector_foreach(&idx->objects, i, entry) {
uint32_t n;
if (entry->offset == UINT32_MAX)
n = htonl(0x80000000 | long_offsets++);
else
n = htonl(entry->offset);
git_filebuf_write(&index_file, &n, sizeof(uint32_t));
}
/* Write out the long offsets */
git_vector_foreach(&idx->objects, i, entry) {
uint32_t split[2];
if (entry->offset != UINT32_MAX)
continue;
split[0] = htonl(entry->offset_long >> 32);
split[1] = htonl(entry->offset_long & 0xffffffff);
git_filebuf_write(&index_file, &split, sizeof(uint32_t) * 2);
}
/* Write out the packfile trailer to the index */
if (git_filebuf_write(&index_file, &trailer_hash, GIT_OID_RAWSZ) < 0)
goto on_error;
/* Write out the hash of the idx */
if (git_filebuf_hash(&trailer_hash, &index_file) < 0)
goto on_error;
git_filebuf_write(&index_file, &trailer_hash, sizeof(git_oid));
/* Figure out what the final name should be */
if (index_path(&filename, idx, ".idx") < 0)
goto on_error;
/* Commit file */
if (git_filebuf_commit_at(&index_file, filename.ptr) < 0)
goto on_error;
git_mwindow_free_all(&idx->pack->mwf);
/* Truncate file to undo rounding up to next page_size in append_to_pack */
if (p_ftruncate(idx->pack->mwf.fd, idx->pack->mwf.size) < 0) {
git_error_set(GIT_ERROR_OS, "failed to truncate pack file '%s'", idx->pack->pack_name);
return -1;
}
if (idx->do_fsync && p_fsync(idx->pack->mwf.fd) < 0) {
git_error_set(GIT_ERROR_OS, "failed to fsync packfile");
goto on_error;
}
/* We need to close the descriptor here so Windows doesn't choke on commit_at */
if (p_close(idx->pack->mwf.fd) < 0) {
git_error_set(GIT_ERROR_OS, "failed to close packfile");
goto on_error;
}
idx->pack->mwf.fd = -1;
if (index_path(&filename, idx, ".pack") < 0)
goto on_error;
/* And don't forget to rename the packfile to its new place. */
if (p_rename(idx->pack->pack_name, git_buf_cstr(&filename)) < 0)
goto on_error;
/* And fsync the parent directory if we're asked to. */
if (idx->do_fsync &&
git_futils_fsync_parent(git_buf_cstr(&filename)) < 0)
goto on_error;
idx->pack_committed = 1;
git_buf_dispose(&filename);
return 0;
on_error:
git_mwindow_free_all(&idx->pack->mwf);
git_filebuf_cleanup(&index_file);
git_buf_dispose(&filename);
return -1;
}