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>
Michael Haggerty
Jeff King
Greg Price
Thomas Rast
Alex Riesen
Junio C Hamano
Johan Herland