add a "oid numbers chunk again

Similar to my 87zhobr4fl.fsf@evledraar.gmail.com, but it works this time.
avar · May 1, 2019 · 3fca63e · 3fca63e
1 parent 83232e3
commit 3fca63e
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Showing 4 changed files with 43 additions and 8 deletions.
diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c
@@ -127,6 +127,14 @@ static int graph_read(int argc, const char **argv)
 		printf(" commit_metadata");
 	if (graph->chunk_extra_edges)
 		printf(" extra_edges");
+	if (getenv("CG_DEBUG") && graph->chunk_oid_numbers)
+		printf(" oid_numbers");
+	if (getenv("CG_DEBUG") && graph->chunk_oid_numbers) {
+		int i;
+		printf("\n");
+		for (i = 0; i < 5; i++)
+			printf("  oid number #%d: %d\n", i, get_be32(graph->chunk_oid_numbers + i * 4));
+	}
 	printf("\n");
 
 	UNLEAK(graph);

diff --git a/commit-graph.c b/commit-graph.c
@@ -22,6 +22,7 @@
 #define GRAPH_CHUNKID_OIDLOOKUP 0x4f49444c /* "OIDL" */
 #define GRAPH_CHUNKID_DATA 0x43444154 /* "CDAT" */
 #define GRAPH_CHUNKID_EXTRAEDGES 0x45444745 /* "EDGE" */
+#define GRAPH_CHUNKID_OIDNUMBERS 0x4f49444e  /* "OIDN" */
 
 #define GRAPH_DATA_WIDTH (the_hash_algo->rawsz + 16)
 
@@ -37,6 +38,7 @@
 #define GRAPH_HEADER_SIZE 8
 #define GRAPH_FANOUT_SIZE (4 * 256)
 #define GRAPH_CHUNKLOOKUP_WIDTH 12
+#define GRAPH_OIDNUMBERS_SIZE (4 * 5)
 #define GRAPH_MIN_SIZE (GRAPH_HEADER_SIZE + 4 * GRAPH_CHUNKLOOKUP_WIDTH \
 			+ GRAPH_FANOUT_SIZE + the_hash_algo->rawsz)
 
@@ -190,6 +192,8 @@ struct commit_graph *parse_commit_graph(void *graph_map, int fd,
 
 	graph->hash_len = the_hash_algo->rawsz;
 	graph->num_chunks = *(unsigned char*)(data + 6);
+	if (getenv("CG_DEBUG"))
+		fprintf(stderr, "have %d chunks\n", graph->num_chunks);
 	graph->graph_fd = fd;
 	graph->data = graph_map;
 	graph->data_len = graph_size;
@@ -210,6 +214,8 @@ struct commit_graph *parse_commit_graph(void *graph_map, int fd,
 		}
 
 		chunk_id = get_be32(chunk_lookup + 0);
+		if (getenv("CG_DEBUG"))
+			fprintf(stderr, "looking at chunk %d with id 0x%X\n", i, chunk_id);
 		chunk_offset = get_be64(chunk_lookup + 4);
 
 		chunk_lookup += GRAPH_CHUNKLOOKUP_WIDTH;
@@ -249,6 +255,12 @@ struct commit_graph *parse_commit_graph(void *graph_map, int fd,
 			else
 				graph->chunk_extra_edges = data + chunk_offset;
 			break;
+		case GRAPH_CHUNKID_OIDNUMBERS:
+			if (graph->chunk_oid_numbers)
+				chunk_repeated = 1;
+			else
+				graph->chunk_oid_numbers = data + chunk_offset;
+			break;
 		}
 
 		if (chunk_repeated) {
@@ -558,6 +570,14 @@ static void write_graph_chunk_oids(struct hashfile *f, int hash_len,
 	}
 }
 
+static void write_graph_chunk_numbers(struct hashfile *f, int hash_len)
+{
+	int i;
+	for (i = 0; i < GRAPH_OIDNUMBERS_SIZE / 4; i++) {
+		hashwrite_be32(f, 1234 + i);
+	}
+}
+
 static const unsigned char *commit_to_sha1(size_t index, void *table)
 {
 	struct commit **commits = table;
@@ -873,8 +893,8 @@ void write_commit_graph(const char *obj_dir,
 	uint32_t i, count_distinct = 0;
 	char *graph_name;
 	struct lock_file lk = LOCK_INIT;
-	uint32_t chunk_ids[5];
-	uint64_t chunk_offsets[5];
+	uint32_t chunk_ids[6];
+	uint64_t chunk_offsets[6];
 	int num_chunks;
 	int num_extra_edges;
 	struct commit_list *parent;
@@ -1036,7 +1056,7 @@ void write_commit_graph(const char *obj_dir,
 
 		commits.nr++;
 	}
-	num_chunks = num_extra_edges ? 4 : 3;
+	num_chunks = num_extra_edges ? 5 : 4;
 	stop_progress(&progress);
 
 	if (commits.nr >= GRAPH_EDGE_LAST_MASK)
@@ -1068,13 +1088,16 @@ void write_commit_graph(const char *obj_dir,
 		chunk_ids[3] = GRAPH_CHUNKID_EXTRAEDGES;
 	else
 		chunk_ids[3] = 0;
-	chunk_ids[4] = 0;
+	chunk_ids[4] = GRAPH_CHUNKID_OIDNUMBERS;
+	chunk_ids[5] = 0;
 
 	chunk_offsets[0] = 8 + (num_chunks + 1) * GRAPH_CHUNKLOOKUP_WIDTH;
 	chunk_offsets[1] = chunk_offsets[0] + GRAPH_FANOUT_SIZE;
 	chunk_offsets[2] = chunk_offsets[1] + hashsz * commits.nr;
 	chunk_offsets[3] = chunk_offsets[2] + (hashsz + 16) * commits.nr;
 	chunk_offsets[4] = chunk_offsets[3] + 4 * num_extra_edges;
+	chunk_offsets[5] = chunk_offsets[4] + GRAPH_OIDNUMBERS_SIZE;
+
 
 	for (i = 0; i <= num_chunks; i++) {
 		uint32_t chunk_write[3];
@@ -1100,6 +1123,7 @@ void write_commit_graph(const char *obj_dir,
 	write_graph_chunk_data(f, hashsz, commits.list, commits.nr, progress, &progress_cnt);
 	if (num_extra_edges)
 		write_graph_chunk_extra_edges(f, commits.list, commits.nr, progress, &progress_cnt);
+	write_graph_chunk_numbers(f, hashsz);
 	stop_progress(&progress);
 	strbuf_release(&progress_title);
 

diff --git a/commit-graph.h b/commit-graph.h
@@ -52,6 +52,7 @@ struct commit_graph {
 	const unsigned char *chunk_oid_lookup;
 	const unsigned char *chunk_commit_data;
 	const unsigned char *chunk_extra_edges;
+	const unsigned char *chunk_oid_numbers;
 };
 
 struct commit_graph *load_commit_graph_one_fd_st(int fd, struct stat *st);

diff --git a/t/t5318-commit-graph.sh b/t/t5318-commit-graph.sh
@@ -58,11 +58,11 @@ graph_git_behavior 'no graph' full commits/3 commits/1
 
 graph_read_expect() {
 	OPTIONAL=""
-	NUM_CHUNKS=3
+	NUM_CHUNKS=4
 	if test ! -z $2
 	then
 		OPTIONAL=" $2"
-		NUM_CHUNKS=$((3 + $(echo "$2" | wc -w)))
+		NUM_CHUNKS=$((4 + $(echo "$2" | wc -w)))
 	fi
 	cat >expect <<- EOF
 	header: 43475048 1 1 $NUM_CHUNKS 0
@@ -340,7 +340,8 @@ GRAPH_BYTE_HASH=5
 GRAPH_BYTE_CHUNK_COUNT=6
 GRAPH_CHUNK_LOOKUP_OFFSET=8
 GRAPH_CHUNK_LOOKUP_WIDTH=12
-GRAPH_CHUNK_LOOKUP_ROWS=5
+GRAPH_CHUNK_OID_NUMBERS_WIDTH=20
+GRAPH_CHUNK_LOOKUP_ROWS=6
 GRAPH_BYTE_OID_FANOUT_ID=$GRAPH_CHUNK_LOOKUP_OFFSET
 GRAPH_BYTE_OID_LOOKUP_ID=$(($GRAPH_CHUNK_LOOKUP_OFFSET + \
 			    1 * $GRAPH_CHUNK_LOOKUP_WIDTH))
@@ -364,7 +365,8 @@ GRAPH_COMMIT_DATA_WIDTH=$(($HASH_LEN + 16))
 GRAPH_OCTOPUS_DATA_OFFSET=$(($GRAPH_COMMIT_DATA_OFFSET + \
 			     $GRAPH_COMMIT_DATA_WIDTH * $NUM_COMMITS))
 GRAPH_BYTE_OCTOPUS=$(($GRAPH_OCTOPUS_DATA_OFFSET + 4))
-GRAPH_BYTE_FOOTER=$(($GRAPH_OCTOPUS_DATA_OFFSET + 4 * $NUM_OCTOPUS_EDGES))
+GRAPH_BYTE_FOOTER=$(($GRAPH_OCTOPUS_DATA_OFFSET + 4 * $NUM_OCTOPUS_EDGES + \
+		    $GRAPH_CHUNK_OID_NUMBERS_WIDTH))
 
 corrupt_graph_setup() {
 	cd "$TRASH_DIRECTORY/full" &&