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[PATCH v2 09/42] pack-objects: abstract away hash algorithm

From
brian m. carlson <sandals@crustytoothpaste.net>
Date
May 2, 2018, 00:25 UTC
Message-ID
<20180502002610.915892-10-sandals@crustytoothpaste.net>
In-Reply-To
<20180502002610.915892-1-sandals@crustytoothpaste.net>

Instead of using hard-coded instances of the constant 20, use the_hash_algo to look up the correct constant.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
---
 builtin/pack-objects.c | 30 ++++++++++++++++--------------
 1 file changed, 16 insertions(+), 14 deletions(-)
diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index 907e112331..f014523613 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -264,6 +264,7 @@ static unsigned long write_no_reuse_object(struct hashfile *f, struct object_ent
 	enum object_type type;
 	void *buf;
 	struct git_istream *st = NULL;
+	const unsigned hashsz = the_hash_algo->rawsz;
 
 	if (!usable_delta) {
 		if (entry->type == OBJ_BLOB &&
@@ -320,7 +321,7 @@ static unsigned long write_no_reuse_object(struct hashfile *f, struct object_ent
 		dheader[pos] = ofs & 127;
 		while (ofs >>= 7)
 			dheader[--pos] = 128 | (--ofs & 127);
-		if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
+		if (limit && hdrlen + sizeof(dheader) - pos + datalen + hashsz >= limit) {
 			if (st)
 				close_istream(st);
 			free(buf);
@@ -332,19 +333,19 @@ static unsigned long write_no_reuse_object(struct hashfile *f, struct object_ent
 	} else if (type == OBJ_REF_DELTA) {
 		/*
 		 * Deltas with a base reference contain
-		 * an additional 20 bytes for the base sha1.
+		 * additional bytes for the base object ID.
 		 */
-		if (limit && hdrlen + 20 + datalen + 20 >= limit) {
+		if (limit && hdrlen + hashsz + datalen + hashsz >= limit) {
 			if (st)
 				close_istream(st);
 			free(buf);
 			return 0;
 		}
 		hashwrite(f, header, hdrlen);
-		hashwrite(f, entry->delta->idx.oid.hash, 20);
-		hdrlen += 20;
+		hashwrite(f, entry->delta->idx.oid.hash, hashsz);
+		hdrlen += hashsz;
 	} else {
-		if (limit && hdrlen + datalen + 20 >= limit) {
+		if (limit && hdrlen + datalen + hashsz >= limit) {
 			if (st)
 				close_istream(st);
 			free(buf);
@@ -376,6 +377,7 @@ static off_t write_reuse_object(struct hashfile *f, struct object_entry *entry,
 	unsigned char header[MAX_PACK_OBJECT_HEADER],
 		      dheader[MAX_PACK_OBJECT_HEADER];
 	unsigned hdrlen;
+	const unsigned hashsz = the_hash_algo->rawsz;
 
 	if (entry->delta)
 		type = (allow_ofs_delta && entry->delta->idx.offset) ?
@@ -411,7 +413,7 @@ static off_t write_reuse_object(struct hashfile *f, struct object_entry *entry,
 		dheader[pos] = ofs & 127;
 		while (ofs >>= 7)
 			dheader[--pos] = 128 | (--ofs & 127);
-		if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
+		if (limit && hdrlen + sizeof(dheader) - pos + datalen + hashsz >= limit) {
 			unuse_pack(&w_curs);
 			return 0;
 		}
@@ -420,16 +422,16 @@ static off_t write_reuse_object(struct hashfile *f, struct object_entry *entry,
 		hdrlen += sizeof(dheader) - pos;
 		reused_delta++;
 	} else if (type == OBJ_REF_DELTA) {
-		if (limit && hdrlen + 20 + datalen + 20 >= limit) {
+		if (limit && hdrlen + hashsz + datalen + hashsz >= limit) {
 			unuse_pack(&w_curs);
 			return 0;
 		}
 		hashwrite(f, header, hdrlen);
-		hashwrite(f, entry->delta->idx.oid.hash, 20);
-		hdrlen += 20;
+		hashwrite(f, entry->delta->idx.oid.hash, hashsz);
+		hdrlen += hashsz;
 		reused_delta++;
 	} else {
-		if (limit && hdrlen + datalen + 20 >= limit) {
+		if (limit && hdrlen + datalen + hashsz >= limit) {
 			unuse_pack(&w_curs);
 			return 0;
 		}
@@ -752,7 +754,7 @@ static off_t write_reused_pack(struct hashfile *f)
 		die_errno("unable to seek in reused packfile");
 
 	if (reuse_packfile_offset < 0)
-		reuse_packfile_offset = reuse_packfile->pack_size - 20;
+		reuse_packfile_offset = reuse_packfile->pack_size - the_hash_algo->rawsz;
 
 	total = to_write = reuse_packfile_offset - sizeof(struct pack_header);
 
@@ -1438,7 +1440,7 @@ static void check_object(struct object_entry *entry)
 			if (reuse_delta && !entry->preferred_base)
 				base_ref = use_pack(p, &w_curs,
 						entry->in_pack_offset + used, NULL);
-			entry->in_pack_header_size = used + 20;
+			entry->in_pack_header_size = used + the_hash_algo->rawsz;
 			break;
 		case OBJ_OFS_DELTA:
 			buf = use_pack(p, &w_curs,
@@ -1850,7 +1852,7 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
 	/* Now some size filtering heuristics. */
 	trg_size = trg_entry->size;
 	if (!trg_entry->delta) {
-		max_size = trg_size/2 - 20;
+		max_size = trg_size/2 - the_hash_algo->rawsz;
 		ref_depth = 1;
 	} else {
 		max_size = trg_entry->delta_size;
Previous: brian m. carlsonNext: brian m. carlson
Message 15 of 45 in “object_id part 13”
  1. 00/42 object_id part 13brian m. carlson, May 2, 2018
  2. 01/42 cache: add a function to read an object ID from a bufferbrian m. carlson, May 2, 2018
  3. 02/42 server-info: remove unused members from struct pack_infobrian m. carlson, May 2, 2018
  4. 06/42 sha1-file: convert freshen functions to object_idbrian m. carlson, May 2, 2018
  5. 07/42 packfile: convert find_pack_entry to object_idbrian m. carlson, May 2, 2018
  6. 11/42 tree-walk: avoid hard-coded 20 constantbrian m. carlson, May 2, 2018
  7. 05/42 packfile: convert has_sha1_pack to object_idbrian m. carlson, May 2, 2018
  8. 13/42 fsck: convert static functions to struct object_idbrian m. carlson, May 2, 2018
  9. 17/42 pack-redundant: convert linked lists to use struct object_idbrian m. carlson, May 2, 2018
  10. 15/42 split-index: convert struct split_index to object_idbrian m. carlson, May 2, 2018
  11. 14/42 submodule-config: convert structures to object_idbrian m. carlson, May 2, 2018
  12. 18/42 index-pack: abstract away hash function constantbrian m. carlson, May 2, 2018
  13. 12/42 tree-walk: convert get_tree_entry_follow_symlinks to object_idbrian m. carlson, May 2, 2018
  14. 10/42 pack-redundant: abstract away hash algorithmbrian m. carlson, May 2, 2018
  15. 09/42 pack-objects: abstract away hash algorithmbrian m. carlson, May 2, 2018
  16. 27/42 builtin/am: convert uses of EMPTY_TREE_SHA1_BIN to the_hash_algobrian m. carlson, May 2, 2018
  17. 28/42 builtin/merge: switch tree functions to use object_idbrian m. carlson, May 2, 2018
  18. 25/42 builtin/receive-pack: avoid hard-coded constants for push certsbrian m. carlson, May 2, 2018
  19. 35/42 sha1_file: convert cached object code to struct object_idbrian m. carlson, May 2, 2018
  20. 38/42 dir: use the_hash_algo for empty blob object IDbrian m. carlson, May 2, 2018
  21. 37/42 sequencer: use the_hash_algo for empty tree object IDbrian m. carlson, May 2, 2018
  22. 36/42 cache-tree: use is_empty_tree_oidbrian m. carlson, May 2, 2018
  23. 41/42 add--interactive: compute the empty tree valuebrian m. carlson, May 2, 2018
  24. 39/42 sha1_file: only expose empty object constants through git_hash_algobrian m. carlson, May 2, 2018
  25. 26/42 sha1-file: add functions for hex empty tree and blob OIDsbrian m. carlson, May 2, 2018
  26. 42/42 merge-one-file: compute empty blob object IDbrian m. carlson, May 2, 2018
  27. 40/42 Update shell scripts to compute empty tree object IDbrian m. carlson, May 2, 2018
  28. 34/42 builtin/reset: convert use of EMPTY_TREE_SHA1_BINbrian m. carlson, May 2, 2018
  29. 33/42 builtin/receive-pack: convert one use of EMPTY_TREE_SHA1_HEXbrian m. carlson, May 2, 2018
  30. 32/42 wt-status: convert two uses of EMPTY_TREE_SHA1_HEXbrian m. carlson, May 2, 2018
  31. 31/42 submodule: convert several uses of EMPTY_TREE_SHA1_HEXbrian m. carlson, May 2, 2018
  32. 30/42 sequencer: convert one use of EMPTY_TREE_SHA1_HEXbrian m. carlson, May 2, 2018
  33. 29/42 merge: convert empty tree constant to the_hash_algobrian m. carlson, May 2, 2018
  34. 23/42 upload-pack: replace use of several hard-coded constantsbrian m. carlson, May 2, 2018
  35. 22/42 revision: replace use of hard-coded constantsbrian m. carlson, May 2, 2018
  36. 24/42 diff: specify abbreviation size in terms of the_hash_algobrian m. carlson, May 2, 2018
  37. 16/42 Update struct index_state to use struct object_idbrian m. carlson, May 2, 2018
  38. 21/42 http: eliminate hard-coded constantsbrian m. carlson, May 2, 2018
  39. 20/42 dir: convert struct untracked_cache_dir to object_idbrian m. carlson, May 2, 2018
  40. 19/42 commit: convert uses of get_sha1_hex to get_oid_hexbrian m. carlson, May 2, 2018
  41. 08/42 packfile: abstract away hash constant valuesbrian m. carlson, May 2, 2018
  42. 04/42 packfile: remove unused member from struct pack_entrybrian m. carlson, May 2, 2018
  43. 03/42 Remove unused member in struct object_contextbrian m. carlson, May 2, 2018
  44. Duy NguyenMay 2, 2018
  45. brian m. carlsonMay 2, 2018

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