Older versions of pack-refs did not write peel lines for
refs outside of refs/tags. This meant that on reading the
pack-refs file, we might set the REF_KNOWS_PEELED flag for
such a ref, even though we do not know anything about its
peeled value.
The previous commit updated the writer to always peel, no
matter what the ref is. That means that packed-refs files
written by newer versions of git are fine to be read by both
old and new versions of git. However, we still have the
problem of reading packed-refs files written by older
versions of git, or by other implementations which have not
yet learned the same trick.
The simplest fix would be to always unset the
REF_KNOWS_PEELED flag for refs outside of refs/tags that do
not have a peel line (if it has a peel line, we know it is
valid, but we cannot assume a missing peel line means
anything). But that loses an important optimization, as
upload-pack should not need to load the object pointed to by
refs/heads/foo to determine that it is not a tag.
Instead, we add a "fully-peeled" trait to the packed-refs
file. If it is set, we know that we can trust a missing peel
line to mean that a ref cannot be peeled. Otherwise, we fall
back to assuming nothing.
[commit message and tests by Jeff King <peff@peff.net>]
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we pack an annotated tag ref, we write not only the
sha1 of the tag object along with the ref, but also the sha1
obtained by peeling the tag. This lets readers of the
pack-refs file know the peeled value without having to
actually load the object, speeding up upload-pack's ref
advertisement.
The writer marks a packed-refs file with peeled refs using
the "peeled" trait at the top of the file. When the reader
sees this trait, it knows that each ref is either followed
by its peeled value, or it is not an annotated tag.
However, there is a mismatch between the assumptions of the
reader and writer. The writer will only peel refs under
refs/tags, but the reader does not know this; it will assume
a ref without a peeled value must not be a tag object. Thus
an annotated tag object placed outside of the refs/tags
hierarchy will not have its peeled value printed by
upload-pack.
The simplest way to fix this is to start writing peel values
for all refs. This matches what the reader expects for both
new and old versions of git.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Many call-sites of parse_object assume that they will get a
non-NULL return value; this is not the case if we encounter
an error while parsing the object.
This patch adds a wrapper function around parse_object that
handles dying automatically, and uses it anywhere we
immediately try to access the return value as a non-NULL
pointer (i.e., anywhere that we would currently segfault).
This wrapper may also be useful in other places. The most
obvious one is code like:
o = parse_object(sha1);
if (!o)
die(...);
However, these should not be mechanically converted to
parse_object_or_die, as the die message is sometimes
customized. Later patches can address these sites on a
case-by-case basis.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
handle_one_ref() only adds refs to the cbdata.ref_to_prune list if
(cbdata.flags & PACK_REFS_PRUNE) is set. So any references in this
list at the end of pack_refs() can be pruned unconditionally.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change check_ref_format() to take a flags argument that indicates what
is acceptable in the reference name (analogous to "git
check-ref-format"'s "--allow-onelevel" and "--refspec-pattern"). This
is more convenient for callers and also fixes a failure in the test
suite (and likely elsewhere in the code) by enabling "onelevel" and
"refspec-pattern" to be allowed independently of each other.
Also rename check_ref_format() to check_refname_format() to make it
obvious that it deals with refnames rather than references themselves.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a large repository which uses directories to organize many refs,
"git pack-refs --all --prune" does not improve performance so much
as it should, unless we remove all the now-empty directories as well.
Signed-off-by: Greg Price <price@ksplice.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change calls to die(..., strerror(errno)) to use the new die_errno().
In the process, also make slight style adjustments: at least state
_something_ about the function that failed (instead of just printing
the pathname), and put paths in single quotes.
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This helps to notice when something's going wrong, especially on
systems which lock open files.
I used the following criteria when selecting the code for replacement:
- it was already printing a warning for the unlink failures
- it is in a function which already printing something or is
called from such a function
- it is in a static function, returning void and the function is only
called from a builtin main function (cmd_)
- it is in a function which handles emergency exit (signal handlers)
- it is in a function which is obvously cleaning up the lockfiles
Signed-off-by: Alex Riesen <raa.lkml@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This changes the "die_on_error" boolean parameter to a mere "flags", and
changes the existing callers of hold_lock_file_for_update/append()
functions to pass LOCK_DIE_ON_ERROR.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This moves pack_refs() and underlying functionality into the library,
to make pack-refs functionality easily available to all git programs.
Most of builtin-pack-refs.c has been moved verbatim into a new file
pack-refs.c that is compiled into libgit.a. A corresponding header
file, pack-refs.h, has also been added, declaring pack_refs() and
the #defines associated with the flags parameter to pack_refs().
This patch introduces no other changes in functionality.
Signed-off-by: Johan Herland <johan@herland.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Make every builtin-*.c file #include "builtin.h".
Also takes care of some declaration/definition mismatches.
Signed-off-by: Peter Hagervall <hager@cs.umu.se>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Without this, if the size of refs_file at that point is ever an exact
multiple of BUFSIZ, then an EIO or ENOSPC error on the final write would
not be diagnosed.
It's not worth worrying about EPIPE here.
Although theoretically possible that someone kill this process
with a manual SIGPIPE, it's not at all likely.
Signed-off-by: Jim Meyering <jim@meyering.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This just basically creates a "pack_refs()" function that could be used by
anybody. You pass it in the flags you want as a bitmask (PACK_REFS_ALL and
PACK_REFS_PRUNE), and it will do all the heavy lifting.
Of course, it's still static, and it's all in the builtin-pack-refs.c
file, so it's not actually visible to the outside, but the next step would
be to just move it all to a library file (probably refs.c) and expose it.
Then we could easily make "git gc" do this too.
While I did it, I also made it check the return value of the fflush and
fsync stage, to make sure that we don't overwrite the old packed-refs file
with something that got truncated due to write errors!
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This mechanically converts strncmp() to use prefixcmp(), but only when
the parameters match specific patterns, so that they can be verified
easily. Leftover from this will be fixed in a separate step, including
idiotic conversions like
if (!strncmp("foo", arg, 3))
=>
if (!(-prefixcmp(arg, "foo")))
This was done by using this script in px.perl
#!/usr/bin/perl -i.bak -p
if (/strncmp\(([^,]+), "([^\\"]*)", (\d+)\)/ && (length($2) == $3)) {
s|strncmp\(([^,]+), "([^\\"]*)", (\d+)\)|prefixcmp($1, "$2")|;
}
if (/strncmp\("([^\\"]*)", ([^,]+), (\d+)\)/ && (length($1) == $3)) {
s|strncmp\("([^\\"]*)", ([^,]+), (\d+)\)|(-prefixcmp($2, "$1"))|;
}
and running:
$ git grep -l strncmp -- '*.c' | xargs perl px.perl
Signed-off-by: Junio C Hamano <junkio@cox.net>
Do *NOT* try this on a repository you care about:
git pack-refs --all --prune
git pack-refs
because while the first "pack-refs" does the right thing, the second
pack-refs will totally screw you over.
This is because the second one tries to pack only tags; we should
also pack what are already packed -- otherwise we would lose them.
[jc: with an additional test]
Signed-off-by: Junio C Hamano <junkio@cox.net>
This fixes the previous implementation which failed to optimize
repositories with tons of lightweight tags. The updated
packed-refs format begins with "# packed-refs with:" line that
lists the kind of extended data the file records. Currently,
there is only one such extension defined, "peeled". This stores
the "peeled tag" on a line that immediately follows a line for a
tag object itself in the format "^<sha-1>".
The header line itself and any extended data are ignored by
older implementation, so packed-refs file generated with this
version can still be used by older git. packed-refs made by
older git can of course be used with this version.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Using for_each_tag_ref() to enumerate tags is wrong since it removes
the refs/tags/ prefix, we need to always use for_each_ref() and filter
out non-tag references in the callback.
Signed-off-by: Alexandre Julliard <julliard@winehq.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This changes 'git-pack-refs' to pack only tags by default.
Branches are meant to be updated, either by committing onto it
yourself or tracking remote branches, and packed entries can
become stale easily, but tags are usually "create once and live
forever" and benefit more from packing.
Signed-off-by: Junio C Hamano <junkio@cox.net>
"git pack-refs --prune", after successfully packing the existing
refs, removes the loose ref files. It tries to protect against
race by doing the usual lock_ref_sha1() which makes sure the
contents of the ref has not changed since we last looked at.
Also we do not bother trying to prune what was already packed, and
we do not try pruning symbolic refs.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This adds a "int *flag" parameter to resolve_ref() and makes
for_each_ref() family to call callback function with an extra
"int flag" parameter. They are used to give two bits of
information (REF_ISSYMREF and REF_ISPACKED) about the ref.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This is a long overdue fix to the API for for_each_ref() family
of functions. It allows the callers to specify a callback data
pointer, so that the caller does not have to use static
variables to communicate with the callback funciton.
The updated for_each_ref() family takes a function of type
int (*fn)(const char *, const unsigned char *, void *)
and a void pointer as parameters, and calls the function with
the name of the ref and its SHA-1 with the caller-supplied void
pointer as parameters.
The commit updates two callers, builtin-name-rev.c and
builtin-pack-refs.c as an example.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This also adds some very rudimentary support for the notion of packed
refs. HOWEVER! At this point it isn't used to actually look up a ref
yet, only for listing them (ie "for_each_ref()" and friends see the
packed refs, but none of the other single-ref lookup routines).
Note how we keep two separate lists: one for the loose refs, and one for
the packed refs we read. That's so that we can easily keep the two apart,
and read only one set or the other (and still always make sure that the
loose refs take precedence).
[ From this, it's not actually obvious why we'd keep the two separate
lists, but it's important to have the packed refs on their own list
later on, when I add support for looking up a single loose one.
For that case, we will want to read _just_ the packed refs in case the
single-ref lookup fails, yet we may end up needing the other list at
some point in the future, so keeping them separated is important ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Michael Haggerty