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[PATCH v3 09/12] commit-graph: convert to using the_hash_algo

From
brian m. carlson <sandals@crustytoothpaste.net>
Date
Oct 22, 2018, 02:43 UTC
Message-ID
<20181022024342.489564-10-sandals@crustytoothpaste.net>
In-Reply-To
<20181022024342.489564-1-sandals@crustytoothpaste.net>

Instead of using hard-coded constants for object sizes, use the_hash_algo to look them up. In addition, use a function call to look up the object ID version and produce the correct value. For now, we use version 1, which means to use the default algorithm used in the rest of the repository.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
---
 commit-graph.c | 33 +++++++++++++++++----------------
 1 file changed, 17 insertions(+), 16 deletions(-)
diff --git a/commit-graph.c b/commit-graph.c
index 40c855f185..6763d19288 100644
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -23,16 +23,11 @@
 #define GRAPH_CHUNKID_DATA 0x43444154 /* "CDAT" */
 #define GRAPH_CHUNKID_LARGEEDGES 0x45444745 /* "EDGE" */
 
-#define GRAPH_DATA_WIDTH 36
+#define GRAPH_DATA_WIDTH (the_hash_algo->rawsz + 16)
 
 #define GRAPH_VERSION_1 0x1
 #define GRAPH_VERSION GRAPH_VERSION_1
 
-#define GRAPH_OID_VERSION_SHA1 1
-#define GRAPH_OID_LEN_SHA1 GIT_SHA1_RAWSZ
-#define GRAPH_OID_VERSION GRAPH_OID_VERSION_SHA1
-#define GRAPH_OID_LEN GRAPH_OID_LEN_SHA1
-
 #define GRAPH_OCTOPUS_EDGES_NEEDED 0x80000000
 #define GRAPH_PARENT_MISSING 0x7fffffff
 #define GRAPH_EDGE_LAST_MASK 0x7fffffff
@@ -44,13 +39,18 @@
 #define GRAPH_FANOUT_SIZE (4 * 256)
 #define GRAPH_CHUNKLOOKUP_WIDTH 12
 #define GRAPH_MIN_SIZE (GRAPH_HEADER_SIZE + 4 * GRAPH_CHUNKLOOKUP_WIDTH \
-			+ GRAPH_FANOUT_SIZE + GRAPH_OID_LEN)
+			+ GRAPH_FANOUT_SIZE + the_hash_algo->rawsz)
 
 char *get_commit_graph_filename(const char *obj_dir)
 {
 	return xstrfmt("%s/info/commit-graph", obj_dir);
 }
 
+static uint8_t oid_version(void)
+{
+	return 1;
+}
+
 static struct commit_graph *alloc_commit_graph(void)
 {
 	struct commit_graph *g = xcalloc(1, sizeof(*g));
@@ -125,15 +125,15 @@ struct commit_graph *load_commit_graph_one(const char *graph_file)
 	}
 
 	hash_version = *(unsigned char*)(data + 5);
-	if (hash_version != GRAPH_OID_VERSION) {
+	if (hash_version != oid_version()) {
 		error(_("hash version %X does not match version %X"),
-		      hash_version, GRAPH_OID_VERSION);
+		      hash_version, oid_version());
 		goto cleanup_fail;
 	}
 
 	graph = alloc_commit_graph();
 
-	graph->hash_len = GRAPH_OID_LEN;
+	graph->hash_len = the_hash_algo->rawsz;
 	graph->num_chunks = *(unsigned char*)(data + 6);
 	graph->graph_fd = fd;
 	graph->data = graph_map;
@@ -149,7 +149,7 @@ struct commit_graph *load_commit_graph_one(const char *graph_file)
 
 		chunk_lookup += GRAPH_CHUNKLOOKUP_WIDTH;
 
-		if (chunk_offset > graph_size - GIT_MAX_RAWSZ) {
+		if (chunk_offset > graph_size - the_hash_algo->rawsz) {
 			error(_("improper chunk offset %08x%08x"), (uint32_t)(chunk_offset >> 32),
 			      (uint32_t)chunk_offset);
 			goto cleanup_fail;
@@ -764,6 +764,7 @@ void write_commit_graph(const char *obj_dir,
 	int num_extra_edges;
 	struct commit_list *parent;
 	struct progress *progress = NULL;
+	const unsigned hashsz = the_hash_algo->rawsz;
 
 	if (!commit_graph_compatible(the_repository))
 		return;
@@ -909,7 +910,7 @@ void write_commit_graph(const char *obj_dir,
 	hashwrite_be32(f, GRAPH_SIGNATURE);
 
 	hashwrite_u8(f, GRAPH_VERSION);
-	hashwrite_u8(f, GRAPH_OID_VERSION);
+	hashwrite_u8(f, oid_version());
 	hashwrite_u8(f, num_chunks);
 	hashwrite_u8(f, 0); /* unused padding byte */
 
@@ -924,8 +925,8 @@ void write_commit_graph(const char *obj_dir,
 
 	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] + GRAPH_OID_LEN * commits.nr;
-	chunk_offsets[3] = chunk_offsets[2] + (GRAPH_OID_LEN + 16) * commits.nr;
+	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;
 
 	for (i = 0; i <= num_chunks; i++) {
@@ -938,8 +939,8 @@ void write_commit_graph(const char *obj_dir,
 	}
 
 	write_graph_chunk_fanout(f, commits.list, commits.nr);
-	write_graph_chunk_oids(f, GRAPH_OID_LEN, commits.list, commits.nr);
-	write_graph_chunk_data(f, GRAPH_OID_LEN, commits.list, commits.nr);
+	write_graph_chunk_oids(f, hashsz, commits.list, commits.nr);
+	write_graph_chunk_data(f, hashsz, commits.list, commits.nr);
 	write_graph_chunk_large_edges(f, commits.list, commits.nr);
 
 	close_commit_graph(the_repository);
Previous: brian m. carlsonNext: Derrick Stolee
Message 9 of 17 in “Base SHA-256 implementation”
  1. 00/12 Base SHA-256 implementationbrian m. carlson, Oct 22, 2018
  2. 01/12 sha1-file: rename algorithm to "sha1"brian m. carlson, Oct 22, 2018
  3. 02/12 sha1-file: provide functions to look up hash algorithmsbrian m. carlson, Oct 22, 2018
  4. 03/12 hex: introduce functions to print arbitrary hashesbrian m. carlson, Oct 22, 2018
  5. 04/12 cache: make hashcmp and hasheq work with larger hashesbrian m. carlson, Oct 22, 2018
  6. 05/12 t: add basic tests for our SHA-1 implementationbrian m. carlson, Oct 22, 2018
  7. 06/12 t: make the sha1 test-tool helper genericbrian m. carlson, Oct 22, 2018
  8. 07/12 sha1-file: add a constant for hash block sizebrian m. carlson, Oct 22, 2018
  9. 09/12 commit-graph: convert to using the_hash_algobrian m. carlson, Oct 22, 2018
  10. Derrick StoleeOct 24, 2018
  11. 08/12 t/helper: add a test helper to compute hash speedbrian m. carlson, Oct 22, 2018
  12. 11/12 sha256: add an SHA-256 implementation using libgcryptbrian m. carlson, Oct 22, 2018
  13. 10/12 Add a base implementation of SHA-256 supportbrian m. carlson, Oct 22, 2018
  14. SZEDER GáborOct 22, 2018
  15. brian m. carlsonOct 23, 2018
  16. Jakub NarebskiOct 27, 2018
  17. 12/12 hash: add an SHA-256 implementation using OpenSSLbrian m. carlson, Oct 22, 2018

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