[PATCH] fetch-pack: optionally save packs to disk
- From
- Augie Fackler <augie@google.com>
- Date
- Jun 11, 2015, 17:44 UTC
- Message-ID
- <1434044676-2942-1-git-send-email-augie@google.com>
When developing server software, it's often helpful to save a potentially-bogus pack for later analysis. This makes that trivial, instead of painful. This is made a little complicated by the fact that in some cases (like cloning from smart-http, but not from a local repo) the fetch code reads the pack header before sending the pack to index-pack (which then gets a --pack_header flag). The included tests cover both of these cases.
To use the new feature, set GIT_SAVE_FETCHED_PACK_TO to a file path and git-fetch will do the rest. The resulting pack can be examined with git-index-pack or similar tools (although if it's corrupt, custom tools can be especially helpful.) --- fetch-pack.c | 44 ++++++++++++++++++++++++++++++++++++++++---- t/t5551-http-fetch-smart.sh | 12 ++++++++++++ t/t5601-clone.sh | 9 +++++++++ 3 files changed, 61 insertions(+), 4 deletions(-)
diff --git a/fetch-pack.c b/fetch-pack.c index a912935..fe6ba58 100644 --- a/fetch-pack.c +++ b/fetch-pack.c @@ -684,7 +684,7 @@ static int get_pack(struct fetch_pack_args *args, const char *argv[22]; char keep_arg[256]; char hdr_arg[256]; - const char **av, *cmd_name; + const char **av, *cmd_name, *savepath; int do_keep = args->keep_pack; struct child_process cmd = CHILD_PROCESS_INIT; int ret; @@ -708,9 +708,8 @@ static int get_pack(struct fetch_pack_args *args, cmd.argv = argv; av = argv; *hdr_arg = 0; + struct pack_header header; if (!args->keep_pack && unpack_limit) { - struct pack_header header; - if (read_pack_header(demux.out, &header)) die("protocol error: bad pack header"); snprintf(hdr_arg, sizeof(hdr_arg), @@ -762,7 +761,44 @@ static int get_pack(struct fetch_pack_args *args, *av++ = "--strict"; *av++ = NULL; - cmd.in = demux.out; + savepath = getenv("GIT_SAVE_FETCHED_PACK_TO"); + if (savepath) { + struct child_process cmd2 = CHILD_PROCESS_INIT; + const char *argv2[22]; + int pipefds[2]; + int e; + const char **av2; + cmd2.argv = argv2; + av2 = argv2; + *av2++ = "tee"; + if (*hdr_arg) { + /* hdr_arg being nonempty means we already read the + * pack header from demux, so we need to drop a pack + * header in place for tee to append to, otherwise + * we'll end up with a broken pack on disk. + */ + int fp; + struct sha1file *s; + fp = open(savepath, O_CREAT | O_TRUNC | O_WRONLY, 0666); + s = sha1fd_throughput(fp, savepath, NULL); + sha1write(s, &header, sizeof(header)); + sha1flush(s); + close(fp); + /* -a is supported by both GNU and BSD tee */ + *av2++ = "-a"; + } + *av2++ = savepath; + *av2++ = NULL; + cmd2.in = demux.out; + e = pipe(pipefds); + if (e != 0) + die("couldn't make pipe to save pack"); + cmd2.out = pipefds[1]; + cmd.in = pipefds[0]; + if (start_command(&cmd2)) + die("couldn't start tee to save a pack"); + } else + cmd.in = demux.out; cmd.git_cmd = 1; if (start_command(&cmd)) die("fetch-pack: unable to fork off %s", cmd_name); diff --git a/t/t5551-http-fetch-smart.sh b/t/t5551-http-fetch-smart.sh index 58207d8..bf4640d 100755 --- a/t/t5551-http-fetch-smart.sh +++ b/t/t5551-http-fetch-smart.sh @@ -82,11 +82,23 @@ test_expect_success 'fetch changes via http' ' test_cmp file clone/file ' +test_expect_success 'fetch changes via http and save pack' ' + echo content >>file && + git commit -a -m two && + git push public && + GIT_SAVE_FETCHED_PACK_TO=saved.pack && + export GIT_SAVE_FETCHED_PACK_TO && + (cd clone && git pull) && + git index-pack clone/saved.pack +' + cat >exp <<EOF GET /smart/repo.git/info/refs?service=git-upload-pack HTTP/1.1 200 POST /smart/repo.git/git-upload-pack HTTP/1.1 200 GET /smart/repo.git/info/refs?service=git-upload-pack HTTP/1.1 200 POST /smart/repo.git/git-upload-pack HTTP/1.1 200 +GET /smart/repo.git/info/refs?service=git-upload-pack HTTP/1.1 200 +POST /smart/repo.git/git-upload-pack HTTP/1.1 200 EOF test_expect_success 'used upload-pack service' ' sed -e " diff --git a/t/t5601-clone.sh b/t/t5601-clone.sh index bfdaf75..73f9e1c 100755 --- a/t/t5601-clone.sh +++ b/t/t5601-clone.sh @@ -40,6 +40,15 @@ test_expect_success C_LOCALE_OUTPUT 'output from clone' ' test $(grep Clon output | wc -l) = 1 ' +test_expect_success 'clone allows saving a pack' ' + rm -fr dst saved.pack && + GIT_SAVE_FETCHED_PACK_TO=saved.pack && + export GIT_SAVE_FETCHED_PACK_TO && + git clone -n "file://$(pwd)/src" dst >output 2>&1 && + test -e saved.pack && + git index-pack saved.pack +' + test_expect_success 'clone does not keep pack' ' rm -fr dst &&
-- 2.4.3.369.gda395ba.dirty