From: Luke Kenneth Casson Leighton <luke.leighton@gmail.com>
Date: Sat, 04 Sep 2010 13:14:36 GMT
Subject: Re: git pack/unpack over bittorrent - works!
Message-ID: <AANLkTik9awEd40s3r-O8t9DwZBh34Z0ozsxMm1QNjNoT@mail.gmail.com>
In-Reply-To: <AANLkTi=7jUSCNiPf+HfEQuxaf16Jt06--bFE7=Of9wp=@mail.gmail.com>

On Sat, Sep 4, 2010 at 12:58 PM, Luke Kenneth Casson Leighton
<luke.leighton@gmail.com> wrote:
> ok, there's one other question i need some info on (thank you to
> nguyen for answering about git cat-file): is there a way to make
> git-pack-objects _just_ give the index file, rather than go to all the
> trouble of creating the pack file as well?
>
> the reason i ask is because i would like to get the index file, parse
> it for objects (as nicolas recommends) then present the contents of
> "git cat-file" as files within subdirectories, via this
> pseudo-VFS-layer over bittorrent.

pack-objects.c - write_pack_file():
...
        if (pack_to_stdout) {
            sha1close(f, sha1, CSUM_CLOSE);
        } else if (nr_written == nr_remaining) {
            sha1close(f, sha1, CSUM_FSYNC);
        } else {
            int fd = sha1close(f, sha1, 0);
            fixup_pack_header_footer(fd, sha1, pack_tmp_name,
                         nr_written, sha1, offset);
            close(fd);
        }

        if (!pack_to_stdout) {
            struct stat st;
            const char *idx_tmp_name;
            char tmpname[PATH_MAX];

            idx_tmp_name = write_idx_file(NULL, written_list,
                              nr_written, sha1);

....

ahh, whoops.  any advances on that?

grep write_idx_file *.c */*.c

* git-index-pack requires a pack file in order to re-create the index:
i don't want that
* git-pack-objects appears to have no way of telling it "just gimme
index file please"
* fast-import.c appears not to be what's needed either.

so - any other methods for just getting the index file (exclusively?)
any other commands i've missed?  if not, are there any other ways of
getting a pack's index of objects without err... getting the index
file?  (i believe the answer to be no, but i'm just making sure) and
on that basis i believe it is safe to ask: any objections to a patch
which adds "--index-only" to builtin/pack-objects.c?

l.