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[PATCH 08/12] pack-write: switch various SHA-1 values to abstract forms

From
brian m. carlson <sandals@crustytoothpaste.net>
Date
Jan 28, 2018, 15:57 UTC
Message-ID
<20180128155722.880805-9-sandals@crustytoothpaste.net>
In-Reply-To
<20180128155722.880805-1-sandals@crustytoothpaste.net>

Convert various uses of hardcoded 20- and 40-based numbers to use the_hash_algo, along with direct calls to SHA-1. Adjust the names of variables to refer to "hash" instead of "sha1".

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
---
 pack-write.c | 49 +++++++++++++++++++++++++------------------------
 1 file changed, 25 insertions(+), 24 deletions(-)
diff --git a/pack-write.c b/pack-write.c
index fea6284192..fe33f7464c 100644
--- a/pack-write.c
+++ b/pack-write.c
@@ -122,7 +122,7 @@ const char *write_idx_file(const char *index_name, struct pack_idx_entry **objec
 			uint32_t offset = htonl(obj->offset);
 			sha1write(f, &offset, 4);
 		}
-		sha1write(f, obj->oid.hash, 20);
+		sha1write(f, obj->oid.hash, the_hash_algo->rawsz);
 		if ((opts->flags & WRITE_IDX_STRICT) &&
 		    (i && !oidcmp(&list[-2]->oid, &obj->oid)))
 			die("The same object %s appears twice in the pack",
@@ -169,7 +169,7 @@ const char *write_idx_file(const char *index_name, struct pack_idx_entry **objec
 		}
 	}
 
-	sha1write(f, sha1, 20);
+	sha1write(f, sha1, the_hash_algo->rawsz);
 	sha1close(f, NULL, ((opts->flags & WRITE_IDX_VERIFY)
 			    ? CSUM_CLOSE : CSUM_FSYNC));
 	return index_name;
@@ -203,20 +203,20 @@ off_t write_pack_header(struct sha1file *f, uint32_t nr_entries)
  * interested in the resulting SHA1 of pack data above partial_pack_offset.
  */
 void fixup_pack_header_footer(int pack_fd,
-			 unsigned char *new_pack_sha1,
+			 unsigned char *new_pack_hash,
 			 const char *pack_name,
 			 uint32_t object_count,
-			 unsigned char *partial_pack_sha1,
+			 unsigned char *partial_pack_hash,
 			 off_t partial_pack_offset)
 {
 	int aligned_sz, buf_sz = 8 * 1024;
-	git_SHA_CTX old_sha1_ctx, new_sha1_ctx;
+	git_hash_ctx old_hash_ctx, new_hash_ctx;
 	struct pack_header hdr;
 	char *buf;
 	ssize_t read_result;
 
-	git_SHA1_Init(&old_sha1_ctx);
-	git_SHA1_Init(&new_sha1_ctx);
+	the_hash_algo->init_fn(&old_hash_ctx);
+	the_hash_algo->init_fn(&new_hash_ctx);
 
 	if (lseek(pack_fd, 0, SEEK_SET) != 0)
 		die_errno("Failed seeking to start of '%s'", pack_name);
@@ -228,9 +228,9 @@ void fixup_pack_header_footer(int pack_fd,
 			  pack_name);
 	if (lseek(pack_fd, 0, SEEK_SET) != 0)
 		die_errno("Failed seeking to start of '%s'", pack_name);
-	git_SHA1_Update(&old_sha1_ctx, &hdr, sizeof(hdr));
+	the_hash_algo->update_fn(&old_hash_ctx, &hdr, sizeof(hdr));
 	hdr.hdr_entries = htonl(object_count);
-	git_SHA1_Update(&new_sha1_ctx, &hdr, sizeof(hdr));
+	the_hash_algo->update_fn(&new_hash_ctx, &hdr, sizeof(hdr));
 	write_or_die(pack_fd, &hdr, sizeof(hdr));
 	partial_pack_offset -= sizeof(hdr);
 
@@ -238,28 +238,28 @@ void fixup_pack_header_footer(int pack_fd,
 	aligned_sz = buf_sz - sizeof(hdr);
 	for (;;) {
 		ssize_t m, n;
-		m = (partial_pack_sha1 && partial_pack_offset < aligned_sz) ?
+		m = (partial_pack_hash && partial_pack_offset < aligned_sz) ?
 			partial_pack_offset : aligned_sz;
 		n = xread(pack_fd, buf, m);
 		if (!n)
 			break;
 		if (n < 0)
 			die_errno("Failed to checksum '%s'", pack_name);
-		git_SHA1_Update(&new_sha1_ctx, buf, n);
+		the_hash_algo->update_fn(&new_hash_ctx, buf, n);
 
 		aligned_sz -= n;
 		if (!aligned_sz)
 			aligned_sz = buf_sz;
 
-		if (!partial_pack_sha1)
+		if (!partial_pack_hash)
 			continue;
 
-		git_SHA1_Update(&old_sha1_ctx, buf, n);
+		the_hash_algo->update_fn(&old_hash_ctx, buf, n);
 		partial_pack_offset -= n;
 		if (partial_pack_offset == 0) {
-			unsigned char sha1[20];
-			git_SHA1_Final(sha1, &old_sha1_ctx);
-			if (hashcmp(sha1, partial_pack_sha1) != 0)
+			unsigned char hash[GIT_MAX_RAWSZ];
+			the_hash_algo->final_fn(hash, &old_hash_ctx);
+			if (hashcmp(hash, partial_pack_hash) != 0)
 				die("Unexpected checksum for %s "
 				    "(disk corruption?)", pack_name);
 			/*
@@ -267,23 +267,24 @@ void fixup_pack_header_footer(int pack_fd,
 			 * pack, which also means making partial_pack_offset
 			 * big enough not to matter anymore.
 			 */
-			git_SHA1_Init(&old_sha1_ctx);
+			the_hash_algo->init_fn(&old_hash_ctx);
 			partial_pack_offset = ~partial_pack_offset;
 			partial_pack_offset -= MSB(partial_pack_offset, 1);
 		}
 	}
 	free(buf);
 
-	if (partial_pack_sha1)
-		git_SHA1_Final(partial_pack_sha1, &old_sha1_ctx);
-	git_SHA1_Final(new_pack_sha1, &new_sha1_ctx);
-	write_or_die(pack_fd, new_pack_sha1, 20);
+	if (partial_pack_hash)
+		the_hash_algo->final_fn(partial_pack_hash, &old_hash_ctx);
+	the_hash_algo->final_fn(new_pack_hash, &new_hash_ctx);
+	write_or_die(pack_fd, new_pack_hash, the_hash_algo->rawsz);
 	fsync_or_die(pack_fd, pack_name);
 }
 
 char *index_pack_lockfile(int ip_out)
 {
-	char packname[46];
+	char packname[GIT_MAX_HEXSZ + 6];
+	int len = the_hash_algo->hexsz + 6;
 
 	/*
 	 * The first thing we expect from index-pack's output
@@ -292,9 +293,9 @@ char *index_pack_lockfile(int ip_out)
 	 * case, we need it to remove the corresponding .keep file
 	 * later on.  If we don't get that then tough luck with it.
 	 */
-	if (read_in_full(ip_out, packname, 46) == 46 && packname[45] == '\n') {
+	if (read_in_full(ip_out, packname, len) == len && packname[len-1] == '\n') {
 		const char *name;
-		packname[45] = 0;
+		packname[len-1] = 0;
 		if (skip_prefix(packname, "keep\t", &name))
 			return xstrfmt("%s/pack/pack-%s.keep",
 				       get_object_directory(), name);
Previous: brian m. carlsonNext: Patryk Obara
Message 18 of 22 in “object_id part 11 (the_hash_algo)”
  1. 00/12 object_id part 11 (the_hash_algo)brian m. carlson, Jan 28, 2018
  2. 01/12 hash: move SHA-1 macros to hash.hbrian m. carlson, Jan 28, 2018
  3. 04/12 builtin/unpack-objects: switch uses of SHA-1 to the_hash_algobrian m. carlson, Jan 28, 2018
  4. 05/12 sha1_file: switch uses of SHA-1 to the_hash_algobrian m. carlson, Jan 28, 2018
  5. 06/12 fast-import: switch various uses of SHA-1 to the_hash_algobrian m. carlson, Jan 28, 2018
  6. Patryk ObaraJan 28, 2018
  7. 09/12 read-cache: abstract away uses of SHA-1brian m. carlson, Jan 28, 2018
  8. Eric SunshineJan 28, 2018
  9. brian m. carlsonJan 28, 2018
  10. 12/12 bulk-checkin: abstract SHA-1 usagebrian m. carlson, Jan 28, 2018
  11. 03/12 builtin/index-pack: improve hash function abstractionbrian m. carlson, Jan 28, 2018
  12. 11/12 csum-file: abstract uses of SHA-1brian m. carlson, Jan 28, 2018
  13. 10/12 csum-file: rename sha1file to hashfilebrian m. carlson, Jan 28, 2018
  14. 02/12 hash: create union for hash context allocationbrian m. carlson, Jan 28, 2018
  15. Patryk ObaraJan 28, 2018
  16. brian m. carlsonJan 28, 2018
  17. 07/12 pack-check: convert various uses of SHA-1 to abstract formsbrian m. carlson, Jan 28, 2018
  18. 08/12 pack-write: switch various SHA-1 values to abstract formsbrian m. carlson, Jan 28, 2018
  19. Patryk ObaraJan 28, 2018
  20. brian m. carlsonJan 28, 2018
  21. Patryk ObaraJan 28, 2018
  22. brian m. carlsonJan 28, 2018

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