| Message ID | 2171d31fb2b783371bdc31ba54856dea8224de65.1654623814.git.gitgitgadget@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | bitmap-format.txt: fix some formatting issues and include checksum info | expand |
On Tue, Jun 07, 2022 at 05:43:34PM +0000, Abhradeep Chakraborty via GitGitGadget wrote: > From: Abhradeep Chakraborty <chakrabortyabhradeep79@gmail.com> > > Bitmap file has a trailing checksum at the end of the file. However > there is no information in the bitmap-format documentation about it. > > Add a trailer section to include the trailing checksum info in the > `Documentation/technical/bitmap-format.txt` file. > > Signed-off-by: Abhradeep Chakraborty <chakrabortyabhradeep79@gmail.com> > --- > Documentation/technical/bitmap-format.txt | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/Documentation/technical/bitmap-format.txt b/Documentation/technical/bitmap-format.txt > index f22669b5916..a43d2fe2bbf 100644 > --- a/Documentation/technical/bitmap-format.txt > +++ b/Documentation/technical/bitmap-format.txt > @@ -125,6 +125,10 @@ MIDXs, both the bit-cache and rev-cache extensions are required. > > ** The compressed bitmap itself, see Appendix A. > > + * TRAILER: > + > + Index checksum of the above contents. It is a 20-byte SHA1 checksum. > + I assume by "Index checksum" you are referring to a checksum of the bitmap _index_'s contents. That term is used a little throughout pack-format.txt, but it's foreign to me. Assuming that's how you meant it, a more conventional term (I think) would be just "trailing checksum". It is also not guaranteed to be a SHA-1 checksum, if the repository which wrote the bitmap is in SHA-256 mode. So I would suggest that this addition just read: * TRAILER: Trailing checksum of the preceding contents. Thanks, Taylor
Taylor Blau <me@ttaylorr.com> wrote: > I assume by "Index checksum" you are referring to a checksum of the > bitmap _index_'s contents. Yeah, I meant a checksum of the bitmap file's content. > That term is used a little throughout > pack-format.txt, but it's foreign to me. Assuming that's how you meant > it, a more conventional term (I think) would be just "trailing > checksum". Actually, I copy-paste it from the pack-format.txt file ;). Will surely follow your suggestions. > It is also not guaranteed to be a SHA-1 checksum, if the repository > which wrote the bitmap is in SHA-256 mode. So I would suggest that this > addition just read: > > * TRAILER: > > Trailing checksum of the preceding contents. Got it. Thanks !
diff --git a/Documentation/technical/bitmap-format.txt b/Documentation/technical/bitmap-format.txt index f22669b5916..a43d2fe2bbf 100644 --- a/Documentation/technical/bitmap-format.txt +++ b/Documentation/technical/bitmap-format.txt @@ -125,6 +125,10 @@ MIDXs, both the bit-cache and rev-cache extensions are required. ** The compressed bitmap itself, see Appendix A. + * TRAILER: + + Index checksum of the above contents. It is a 20-byte SHA1 checksum. + == Appendix A: Serialization format for an EWAH bitmap Ewah bitmaps are serialized in the same protocol as the JAVAEWAH