Derrick Stolee <stolee@xxxxxxxxx> writes: > On 2/7/2020 5:16 PM, Johannes Berg wrote: >> The description of the multi-pack-index contains a small bug, >> if all offsets are < 2^32 then there will be no LOFF chunk, >> not only if they're all < 2^31 (since the highest bit is only >> needed as the "LOFF-escape" when that's actually needed.) >> >> Correct this, and clarify that in that case only offsets up >> to 2^31-1 can be stored in the OOFF chunk. >> >> Signed-off-by: Johannes Berg <johannes@xxxxxxxxxxxxxxxx> >> --- >> Documentation/technical/pack-format.txt | 5 +++-- >> 1 file changed, 3 insertions(+), 2 deletions(-) >> >> diff --git a/Documentation/technical/pack-format.txt b/Documentation/technical/pack-format.txt >> index cab5bdd2ff0f..d3a142c65202 100644 >> --- a/Documentation/technical/pack-format.txt >> +++ b/Documentation/technical/pack-format.txt >> @@ -315,10 +315,11 @@ CHUNK DATA: >> Stores two 4-byte values for every object. >> 1: The pack-int-id for the pack storing this object. >> 2: The offset within the pack. >> - If all offsets are less than 2^31, then the large offset chunk >> + If all offsets are less than 2^32, then the large offset chunk >> will not exist and offsets are stored as in IDX v1. >> If there is at least one offset value larger than 2^32-1, then >> - the large offset chunk must exist. If the large offset chunk >> + the large offset chunk must exist, and offsets larger than >> + 2^31-1 must be stored in it instead. If the large offset chunk >> exists and the 31st bit is on, then removing that bit reveals >> the row in the large offsets containing the 8-byte offset of >> this object. > > Thank you for finding this doc bug. This is a very subtle point, > and you have described it very clearly. Thanks, both; queued.
