path: root/Documentation/technical/pack-format.txt
diff options
authorStefan Saasen <>2013-04-12 05:56:24 (GMT)
committerJunio C Hamano <>2013-04-12 16:14:01 (GMT)
commit06cb843fea195ea99391c4daf8018a13ec99c75e (patch)
tree85225713f77b7a7b0f9e92ace2074015c344f863 /Documentation/technical/pack-format.txt
parent2137ce01f83d254e4917c107901a5a04f61e8c16 (diff)
Documentation: distinguish between ref and offset deltas in pack-format
eb32d236 introduced the OBJ_OFS_DELTA object that uses a relative offset to identify the base object instead of the 20-byte SHA1 reference. The pack file documentation only mentions the SHA1 based reference in its description of the deltified object entry. Update the pack format documentation to clarify that the deltified object representation refers to its base using either a relative negative offset or the absolute SHA1 identifier. Signed-off-by: Stefan Saasen <> Signed-off-by: Junio C Hamano <>
Diffstat (limited to 'Documentation/technical/pack-format.txt')
1 files changed, 3 insertions, 1 deletions
diff --git a/Documentation/technical/pack-format.txt b/Documentation/technical/pack-format.txt
index a7871fb..f194d1c 100644
--- a/Documentation/technical/pack-format.txt
+++ b/Documentation/technical/pack-format.txt
@@ -26,7 +26,9 @@ GIT pack format
(deltified representation)
n-byte type and length (3-bit type, (n-1)*7+4-bit length)
- 20-byte base object name
+ 20-byte base object name if OBJ_REF_DELTA or a negative relative
+ offset from the delta object's position in the pack if this
+ is an OBJ_OFS_DELTA object
compressed delta data
Observation: length of each object is encoded in a variable