Function parse_commit_graph

commit-graph.c:373–491

}

struct commit_graph *parse_commit_graph(struct repository *r,
					void *graph_map, size_t graph_size)
{
	const unsigned char *data;
	struct commit_graph *graph;
	uint32_t graph_signature;
	unsigned char graph_version, hash_version;
	struct chunkfile *cf = NULL;

	if (!graph_map)
		return NULL;

	if (graph_size < graph_min_size(r->hash_algo))
		return NULL;

	data = (const unsigned char *)graph_map;

	graph_signature = get_be32(data);
	if (graph_signature != GRAPH_SIGNATURE) {
		error(_("commit-graph signature %X does not match signature %X"),
		      graph_signature, GRAPH_SIGNATURE);
		return NULL;
	}

	graph_version = *(unsigned char*)(data + 4);
	if (graph_version != GRAPH_VERSION) {
		error(_("commit-graph version %X does not match version %X"),
		      graph_version, GRAPH_VERSION);
		return NULL;
	}

	hash_version = *(unsigned char*)(data + 5);
	if (hash_version != oid_version(r->hash_algo)) {
		error(_("commit-graph hash version %X does not match version %X"),
		      hash_version, oid_version(r->hash_algo));
		return NULL;
	}

	graph = alloc_commit_graph();

	graph->hash_algo = r->hash_algo;
	graph->num_chunks = *(unsigned char*)(data + 6);
	graph->data = graph_map;
	graph->data_len = graph_size;

	if (graph_size < GRAPH_HEADER_SIZE +
			 (graph->num_chunks + 1) * CHUNK_TOC_ENTRY_SIZE +
			 GRAPH_FANOUT_SIZE + r->hash_algo->rawsz) {
		error(_("commit-graph file is too small to hold %u chunks"),
		      graph->num_chunks);
		free(graph);
		return NULL;
	}

	cf = init_chunkfile(NULL);

	if (read_table_of_contents(cf, graph->data, graph_size,
				   GRAPH_HEADER_SIZE, graph->num_chunks, 1))