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[PATCH v2 09/13] commit-graph: convert to using the_hash_algo

From
brian m. carlson <sandals@crustytoothpaste.net>
Date
Oct 15, 2018, 02:18 UTC
Message-ID
<20181015021900.1030041-10-sandals@crustytoothpaste.net>
In-Reply-To
<20181015021900.1030041-1-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.

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 7f4519ec3b..7a28fbb03f 100644
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -20,16 +20,11 @@
 #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
@@ -41,13 +36,18 @@
 #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));
@@ -100,15 +100,15 @@ 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;
@@ -124,7 +124,7 @@ 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;
@@ -711,6 +711,7 @@ void write_commit_graph(const char *obj_dir,
 	int num_chunks;
 	int num_extra_edges;
 	struct commit_list *parent;
+	const unsigned hashsz = the_hash_algo->rawsz;
 
 	oids.nr = 0;
 	oids.alloc = approximate_object_count() / 4;
@@ -831,7 +832,7 @@ 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 */
 
@@ -846,8 +847,8 @@ 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++) {
@@ -860,8 +861,8 @@ 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();
Previous: brian m. carlsonNext: Derrick Stolee
Message 16 of 44 in “Base SHA-256 implementation”
  1. 00/13 Base SHA-256 implementationbrian m. carlson, Oct 15, 2018
  2. 01/13 sha1-file: rename algorithm to "sha1"brian m. carlson, Oct 15, 2018
  3. Duy NguyenOct 16, 2018
  4. brian m. carlsonOct 17, 2018
  5. 02/13 sha1-file: provide functions to look up hash algorithmsbrian m. carlson, Oct 15, 2018
  6. SZEDER GáborOct 17, 2018
  7. 04/13 cache: make hashcmp and hasheq work with larger hashesbrian m. carlson, Oct 15, 2018
  8. Duy NguyenOct 16, 2018
  9. 06/13 t: make the sha1 test-tool helper genericbrian m. carlson, Oct 15, 2018
  10. 07/13 sha1-file: add a constant for hash block sizebrian m. carlson, Oct 15, 2018
  11. 03/13 hex: introduce functions to print arbitrary hashesbrian m. carlson, Oct 15, 2018
  12. Junio C HamanoOct 16, 2018
  13. brian m. carlsonOct 17, 2018
  14. 05/13 t: add basic tests for our SHA-1 implementationbrian m. carlson, Oct 15, 2018
  15. 08/13 t/helper: add a test helper to compute hash speedbrian m. carlson, Oct 15, 2018
  16. 09/13 commit-graph: convert to using the_hash_algobrian m. carlson, Oct 15, 2018
  17. Derrick StoleeOct 15, 2018
  18. 11/13 sha256: add an SHA-256 implementation using libgcryptbrian m. carlson, Oct 15, 2018
  19. 12/13 hash: add an SHA-256 implementation using OpenSSLbrian m. carlson, Oct 15, 2018
  20. Duy NguyenOct 16, 2018
  21. 13/13 commit-graph: specify OID version for SHA-256brian m. carlson, Oct 15, 2018
  22. Derrick StoleeOct 15, 2018
  23. Junio C HamanoOct 16, 2018
  24. brian m. carlsonOct 16, 2018
  25. Duy NguyenOct 16, 2018
  26. Derrick StoleeOct 16, 2018
  27. Duy NguyenOct 16, 2018
  28. brian m. carlsonOct 16, 2018
  29. Duy NguyenOct 17, 2018
  30. brian m. carlsonOct 18, 2018
  31. Derrick StoleeOct 18, 2018
  32. brian m. carlsonOct 19, 2018
  33. Derrick StoleeOct 17, 2018
  34. brian m. carlsonOct 17, 2018
  35. 10/13 Add a base implementation of SHA-256 supportbrian m. carlson, Oct 15, 2018
  36. Duy NguyenOct 15, 2018
  37. brian m. carlsonOct 15, 2018
  38. Duy NguyenOct 16, 2018
  39. SZEDER GáborOct 17, 2018
  40. brian m. carlsonOct 17, 2018
  41. Junio C HamanoOct 16, 2018
  42. Junio C HamanoOct 16, 2018
  43. brian m. carlsonOct 16, 2018
  44. Duy NguyenOct 16, 2018

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