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[PATCH v2 03/35] pack-bitmap: make bitmap header handling hash agnostic

From
brian m. carlson <sandals@crustytoothpaste.net>
Date
Feb 19, 2019, 00:04 UTC
Message-ID
<20190219000526.476553-4-sandals@crustytoothpaste.net>
In-Reply-To
<20190219000526.476553-1-sandals@crustytoothpaste.net>

Increase the checksum field in struct bitmap_disk_header to be GIT_MAX_RAWSZ bytes in length and ensure that we hash the proper number of bytes out when computing the bitmap checksum.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
---
 pack-bitmap-write.c | 2 +-
 pack-bitmap.c       | 2 +-
 pack-bitmap.h       | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/pack-bitmap-write.c b/pack-bitmap-write.c
index 5566e94abe..c82fb01fd7 100644
--- a/pack-bitmap-write.c
+++ b/pack-bitmap-write.c
@@ -535,7 +535,7 @@ void bitmap_writer_finish(struct pack_idx_entry **index,
 	header.entry_count = htonl(writer.selected_nr);
 	hashcpy(header.checksum, writer.pack_checksum);
 
-	hashwrite(f, &header, sizeof(header));
+	hashwrite(f, &header, sizeof(header) - GIT_MAX_RAWSZ + the_hash_algo->rawsz);
 	dump_bitmap(f, writer.commits);
 	dump_bitmap(f, writer.trees);
 	dump_bitmap(f, writer.blobs);
diff --git a/pack-bitmap.c b/pack-bitmap.c
index 4695aaf6b4..b53f37243c 100644
--- a/pack-bitmap.c
+++ b/pack-bitmap.c
@@ -163,7 +163,7 @@ static int load_bitmap_header(struct bitmap_index *index)
 	}
 
 	index->entry_count = ntohl(header->entry_count);
-	index->map_pos += sizeof(*header);
+	index->map_pos += sizeof(*header) - GIT_MAX_RAWSZ + the_hash_algo->rawsz;
 	return 0;
 }
 
diff --git a/pack-bitmap.h b/pack-bitmap.h
index 8418ba8c79..344ba23af9 100644
--- a/pack-bitmap.h
+++ b/pack-bitmap.h
@@ -14,7 +14,7 @@ struct bitmap_disk_header {
 	uint16_t version;
 	uint16_t options;
 	uint32_t entry_count;
-	unsigned char checksum[20];
+	unsigned char checksum[GIT_MAX_RAWSZ];
 };
 
 static const char BITMAP_IDX_SIGNATURE[] = {'B', 'I', 'T', 'M'};
Previous: brian m. carlsonNext: brian m. carlson
Message 4 of 36 in “Hash function transition part 16”
  1. 00/35 Hash function transition part 16brian m. carlson, Feb 19, 2019
  2. 01/35 t/lib-submodule-update: use appropriate length constantbrian m. carlson, Feb 19, 2019
  3. 02/35 khash: move oid hash table definitionbrian m. carlson, Feb 19, 2019
  4. 03/35 pack-bitmap: make bitmap header handling hash agnosticbrian m. carlson, Feb 19, 2019
  5. 06/35 pack-bitmap: switch hard-coded constants to the_hash_algobrian m. carlson, Feb 19, 2019
  6. 05/35 pack-bitmap: replace sha1_to_hexbrian m. carlson, Feb 19, 2019
  7. 07/35 pack-bitmap: switch hash tables to use struct object_idbrian m. carlson, Feb 19, 2019
  8. 09/35 notes-merge: switch to use the_hash_algobrian m. carlson, Feb 19, 2019
  9. 08/35 submodule: avoid hard-coded constantsbrian m. carlson, Feb 19, 2019
  10. 11/35 notes: replace sha1_to_hexbrian m. carlson, Feb 19, 2019
  11. 14/35 fast-import: make hash-size independentbrian m. carlson, Feb 19, 2019
  12. 17/35 builtin/pull: make hash-size independentbrian m. carlson, Feb 19, 2019
  13. 15/35 fast-import: replace sha1_to_hexbrian m. carlson, Feb 19, 2019
  14. 12/35 object-store: rename and expand packed_git's sha1 memberbrian m. carlson, Feb 19, 2019
  15. 19/35 http-backend: allow 64-character hex namesbrian m. carlson, Feb 19, 2019
  16. 18/35 http-push: convert to use the_hash_algobrian m. carlson, Feb 19, 2019
  17. 21/35 http-walker: replace sha1_to_hexbrian m. carlson, Feb 19, 2019
  18. 22/35 http: replace hard-coded constant with the_hash_algobrian m. carlson, Feb 19, 2019
  19. 20/35 http-push: remove remaining uses of sha1_to_hexbrian m. carlson, Feb 19, 2019
  20. 23/35 http: compute hash of downloaded objects using the_hash_algobrian m. carlson, Feb 19, 2019
  21. 24/35 http: replace sha1_to_hexbrian m. carlson, Feb 19, 2019
  22. 25/35 remote-curl: make hash size independentbrian m. carlson, Feb 19, 2019
  23. 26/35 hash: add a function to lookup hash algorithm by lengthbrian m. carlson, Feb 19, 2019
  24. 30/35 refspec: make hash size independentbrian m. carlson, Feb 19, 2019
  25. 27/35 get-tar-commit-id: parse comment recordbrian m. carlson, Feb 19, 2019
  26. 29/35 archive: convert struct archiver_args to object_idbrian m. carlson, Feb 19, 2019
  27. 34/35 Git.pm: make hash size independentbrian m. carlson, Feb 19, 2019
  28. 33/35 read-cache: read data in a hash-independent waybrian m. carlson, Feb 19, 2019
  29. 31/35 builtin/difftool: use parse_oid_hexbrian m. carlson, Feb 19, 2019
  30. 35/35 gitweb: make hash size independentbrian m. carlson, Feb 19, 2019
  31. 32/35 dir: make untracked cache extension hash size independentbrian m. carlson, Feb 19, 2019
  32. 16/35 builtin/am: make hash size independentbrian m. carlson, Feb 19, 2019
  33. 28/35 builtin/get-tar-commit-id: make hash size independentbrian m. carlson, Feb 19, 2019
  34. 13/35 builtin/name-rev: make hash-size independentbrian m. carlson, Feb 19, 2019
  35. 04/35 pack-bitmap: convert struct stored_bitmap to object_idbrian m. carlson, Feb 19, 2019
  36. 10/35 notes: make hash size independentbrian m. carlson, Feb 19, 2019

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