In this case we did nothing in the past, but we should delete the
reference in fact.

The problem was that when the symref is not packed but the referenced
ref is packed, then we assumed that the symref is packed as well, but
symrefs are never packed.
Signed-off-by: NMiklos Vajna <vmiklos@frugalware.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

There may be cases where one would really want to rename the symbolic
ref without changing its value, but "git branch -m" is not such a
use-case.
Signed-off-by: NMiklos Vajna <vmiklos@frugalware.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

We tried to check if a reflog of a ref is a symlink without first
checking if it exists, which is a bug.
Signed-off-by: NMiklos Vajna <vmiklos@frugalware.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This had two problems with symrefs. First, it copied the actual sha1
instead of the "pointer", second it failed to remove the old ref after a
successful rename.

Given that till now delete_ref() always dereferenced symrefs, a new
parameters has been introduced to delete_ref() to allow deleting refs
without a dereference.
Signed-off-by: NMiklos Vajna <vmiklos@frugalware.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

When the user specifies a ref by a reflog entry older than
one we have (e.g., "HEAD@{20 years ago"}), we issue a
warning and give them the "from" value of the oldest reflog
entry. That is, we say "we don't know what happened before
this entry, but before this we know we had some particular
SHA1".

However, the oldest reflog entry is often a creation event
such as clone or branch creation. In this case, the entry
claims that the ref went from "00000..." (the null sha1) to
the new value, and the reflog lookup returns the null sha1.

While this is technically correct (the entry tells us that
the ref didn't exist at the specified time) it is not
terribly useful to the end user. What they probably want
instead is "the oldest useful sha1 that this ref ever had".
This patch changes the behavior such that if the oldest ref
would return the null sha1, it instead returns the first
value the ref ever had.

We never discovered this problem in the test scripts because
we created "fake" reflogs that had only a specified segment
of history. This patch updates the tests with a creation
event at the beginning of history.
Signed-off-by: NJeff King <peff@peff.net>
Acked-by: NShawn O. Pearce <spearce@spearce.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

If git attempts to delete a ref, but the unlink of the ref
file fails, we print a message to stderr. This is usually a
good thing, but if the error is ENOENT, then it indicates
that the ref has _already_ been deleted. And since that's
our goal, it doesn't make sense to complain to the user.

This harmonizes the error reporting behavior for the
unpacked and packed cases; the packed case already printed
nothing on ENOENT, but the unpacked printed unconditionally.

Additionally, send-pack would, when deleting the tracking
ref corresponding to a remote delete, print "Failed to
delete" on any failure. This can be a misleading
message, since we actually _did_ delete at the remote side,
but we failed to delete locally. Rather than make the
message more precise, let's just eliminate it entirely; the
delete_ref routine already takes care of printing out a much
more specific message about what went wrong.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

These refs can be anything, but they are most likely useful as
pointing to objects that you know are in the object database but don't
have any regular refs for. For example, when cloning with --reference,
the refs in this repository should be listed as objects that we have,
even though we don't have refs in our newly-created repository for
them yet.
Signed-off-by: NDaniel Barkalow <barkalow@iabervon.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

xread() and xwrite() return ssize_t values as their native POSIX
counterparts read(2) and write(2).

To be consistent, read_in_full() and write_in_full() should also return
ssize_t values.
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

When .git in a submodule is a file, resolve_gitlink_ref() needs to pick up
the real GIT_DIR of the submodule from that file.
Signed-off-by: NLars Hjemli <hjemli@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Currently the only caller of peel_ref is show-ref, which is using
this function to show the peeled tag information if it is available
from an existing packed-refs file.  The call happens during the
for_each_ref callback function, so we have the proper struct ref_list
already on the call stack but it is not easily available to return
the peeled information to the caller.

We now save the current struct ref_list item before calling back
into the callback function so that future calls to peel_ref from
within the callback function can quickly access the current ref.
Doing so will save us an lstat() per ref processed as we no longer
have to check the filesystem to see if the ref exists as a loose
file or is packed.  This current ref caching also saves a linear
scan of the cached packed refs list.

As a micro-optimization we test the address of the passed ref name
against the current_ref->name before we go into the much more costly
strcmp().  Nearly any caller of peel_ref will be passing us the same
string do_for_each_ref passed them, which is current_ref->name.
Signed-off-by: NShawn O. Pearce <spearce@spearce.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

If the SHA-1 we are requesting the object for does not exist in
the object database we get a NULL back.  Accessing the type from
that is not likely to succeed on any system.
Signed-off-by: NShawn O. Pearce <spearce@spearce.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This is in preparation to the reflog-expire changes which will
allow updating the ref after expiring the reflog.
Signed-off-by: NBrandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Instead of calling close_lock_file() and commit_lock_file() directly,
which take a struct lock_file argument, add two new functions:
close_ref() and commit_ref(), which handle calling the previous
lock_file functions and modifying the ref_lock structure.
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Remove remaining double close(2)'s.  i.e. close() before
commit_locked_index() or commit_lock_file().
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This makes write_ref_sha1() more careful: it actually checks the SHA1 of
the ref it is updating, and refuses to update a ref with an object that it
cannot find.

Perhaps more importantly, it also refuses to update a branch head with a
non-commit object. I don't quite know *how* the stable series maintainers
were able to corrupt their repository to have a HEAD that pointed to a tag
rather than a commit object, but they did. Which results in a totally
broken repository that cannot be cloned or committed on.

So make it harder for people to shoot themselves in the foot like that.

The test t1400-update-ref.sh is fixed at the same time, as it
assumed that the commands involved in the particular test would
not care about corrupted repositories whose refs point at
nonexistant bogus objects.  That assumption does not hold true
anymore.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This updates send-pack and fast-import to use symbolic constants
for checking the return values from check_ref_format(), and also
futureproof the logic in lock_any_ref_for_update() to explicitly
name the case that is usually considered an error but is Ok for
this particular use.
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Recent check_ref_format() returns -3 as well as -1 (general
error) and -2 (less than two levels).  The caller was explicitly
checking for -1, to allow "HEAD" but still needed to disallow
bogus refs.

This introduces symbolic constants for the return values from
check_ref_format() to make them read better and more
meaningful.  Normal ref creation codepath can still treat
non-zero return values as errors.
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

An earlier fix to the said commit was incomplete; it mixed up the
meaning of the flag parameter passed to the internal fmt_ident()
function, so this corrects it.

git_author_info() and git_committer_info() can be told to issue a
warning when no usable user information is found, and optionally can be
told to error out.  Operations that actually use the information to
record a new commit or a tag will still error out, but the caller to
leave reflog record will just silently use bogus user information.

Not warning on misconfigured user information while writing a reflog
entry is somewhat debatable, but it is probably nicer to the users to
silently let it pass, because the only information you are losing is who
checked out the branch.

 * git_author_info() and git_committer_info() used to take 1 (positive
   int) to error out with a warning on misconfiguration; this is now
   signalled with a symbolic constant IDENT_ERROR_ON_NO_NAME.

 * These functions used to take -1 (negative int) to warn but continue;
   this is now signalled with a symbolic constant IDENT_WARN_ON_NO_NAME.

 * fmt_ident() function implements the above error reporting behaviour
   common to git_author_info() and git_committer_info().  A symbolic
   constant IDENT_NO_DATE can be or'ed in to the flag parameter to make
   it return only the "Name <email@address.xz>".

 * fmt_name() is a thin wrapper around fmt_ident() that always passes
   IDENT_ERROR_ON_NO_NAME and IDENT_NO_DATE.
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The old rules used by fetch were coded as a series of ifs.  The old
rules are:
1) match full refname if it starts with "refs/" or matches "HEAD"
2) verify that full refname starts with "refs/"
3) match abbreviated name in "refs/" if it starts with "heads/",
    "tags/", or "remotes/".
4) match abbreviated name in "refs/heads/"

This is replaced by the new rules
a) match full refname
b) match abbreviated name prefixed with "refs/"
c) match abbreviated name prefixed with "refs/heads/"

The details of the new rules are different from the old rules.  We no
longer verify that the full refname starts with "refs/".  The new rule
(a) matches any full string.  The old rules (1) and (2) were stricter.
Now, the caller is responsible for using sensible full refnames.  This
should be the case for the current code.  The new rule (b) is less
strict than old rule (3).  The new rule accepts abbreviated names that
start with a non-standard prefix below "refs/".

Despite this modifications the new rules should handle all cases as
expected.  Two tests are added to verify that fetch does not resolve
short tags or HEAD in remotes.

We may even think about loosening the rules a bit more and unify them
with the rev-parse rules.  This would be done by replacing
ref_ref_fetch_rules with ref_ref_parse_rules.  Note, the two new test
would break.
Signed-off-by: NSteffen Prohaska <prohaska@zib.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

We use at least two rulesets for matching abbreviated refnames with
full refnames (starting with 'refs/').  git-rev-parse and git-fetch
use slightly different rules.

This commit introduces a new function refname_match
(const char *abbrev_name, const char *full_name, const char **rules).

abbrev_name is expanded using the rules and matched against full_name.
If a match is found the function returns true.  rules is a NULL-terminate
list of format patterns with "%.*s", for example:

    const char *ref_rev_parse_rules[] = {
               "%.*s",
               "refs/%.*s",
               "refs/tags/%.*s",
               "refs/heads/%.*s",
               "refs/remotes/%.*s",
               "refs/remotes/%.*s/HEAD",
               NULL
    };

Asterisks are included in the format strings because this is the form
required in sha1_name.c.  Sharing the list with the functions there is
a good idea to avoid duplicating the rules.  Hopefully this
facilitates unified matching rules in the future.

This commit makes the rules used by rev-parse for resolving refs to
sha1s available for string comparison.  Before this change, the rules
were buried in get_sha1*() and dwim_ref().

A follow-up commit will refactor the rules used by fetch.

refname_match() will be used for matching refspecs in git-send-pack.

Thanks to Daniel Barkalow <barkalow@iabervon.org> for pointing
out that ref_matches_abbrev in remote.c solves a similar problem
and care should be taken to avoid confusion.
Signed-off-by: NSteffen Prohaska <prohaska@zib.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This was a static in remote.c, but is generally useful.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJohannes Sixt <johannes.sixt@telecom.at>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

There was a function called remove_empty_dir_recursive() buried
in refs.c.  Expose a slightly enhanced version in dir.h: it can now
optionally remove a non-empty directory.
Signed-off-by: NJohannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NPierre Habouzit <madcoder@debian.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

A function intended to be called from builtins updating refs
by locking them before write, specially those that came from
scripts using "git update-ref".

[jc: with minor fixups]
Signed-off-by: NCarlos Rica <jasampler@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

On Windows (it can't touch open files in any way) the following fails:

    git branch -D branch1 branch2

if the both branches are in packed-refs.
Signed-off-by: NAlex Riesen <raa.lkml@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

A reflog file is organized as one-line-per-entry records, and we
enforced the file format integrity by chomping the given message
at the first LF.  This changes it to convert them to SP, which
is more in line with the --pretty=oneline format.
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

These days, show_date() takes a date_mode parameter to specify
the output format, and a separate specialized function for dates
in E-mails does not make much sense anymore.

This retires show_rfc2822_date() function and make it just
another date output format.
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

I audited git for potential undetected write failures.
In the cases fixed below, the diagnostics I add mimic the diagnostics
used in surrounding code, even when that means not reporting
the precise strerror(errno) cause of the error.
Signed-off-by: NJim Meyering <jim@meyering.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

There still are quite a few symbols that ought to be static.
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This means that send-pack and http-push will support pattern refspecs,
so builtin-push.c doesn't have to expand them, and also git push can
just turn --tags into "refs/tags/*", further simplifying
builtin-push.c

check_ref_format() gets a third "conditionally okay" result for
something that's valid as a pattern but not as a particular ref.
Signed-off-by: NDaniel Barkalow <barkalow@iabervon.org>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

git-checkout is also adapted to make use of this new option
instead of the handcrafted command sequence.
Signed-off-by: NSven Verdoolaege <skimo@kotnet.org>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Rather than sorting the refs list while building it, sort in one
go after it is built using a merge sort.  This has a large
performance boost with large numbers of refs.

It shouldn't happen that we read duplicate entries into the same
list, but just in case sort_ref_list drops them if the SHA1s are
the same, or dies, as we have no way of knowing which one is the
correct one.
Signed-off-by: NJulian Phillips <julian@quantumfyre.co.uk>
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

delete_ref function does not change the 'sha1' parameter. Non-const pointer
causes a compiler warning if you call to the function using a const argument.
Signed-off-by: NCarlos Rica <jasampler@gmail.com>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

This new function resolves a ref in *another* git repository.  It's
named for its intended use: to look up the git link to a subproject.

It's not actually wired up to anything yet, but we're getting closer to
having fundamental plumbing support for "links" from one git directory
to another, which is the basis of subproject support.

[jc: amended a FILE* leak]
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

This moves the knowledge about .git/config usage out of refs.c and into
builtin-branch.c instead, which allows git-branch to update HEAD to point
at the moved branch before attempting to update the config file. It also
allows git-branch to exit with an error code if updating the config file
should fail.
Signed-off-by: NLars Hjemli <hjemli@gmail.com>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

If git_config_rename_section() fails, rename_ref() used to return 1, which
left HEAD pointing to an absent refs/heads file (since the actual renaming
had already occurred).
Signed-off-by: NLars Hjemli <hjemli@gmail.com>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

The HEAD reflog is updated as well as the reflog for the branch pointed
to by HEAD whenever it is referenced with "HEAD".

There are some cases where a specific branch may be modified directly.
In those cases, the HEAD reflog should be updated as well if it is a
symref to that branch in order to be consistent.
Signed-off-by: NNicolas Pitre <nico@cam.org>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Without this, committing in a group-shared repository would not work
even though all developers are in the same group.
Signed-off-by: NMatthias Kestenholz <matthias@spinlock.ch>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

Some systems have sizeof(off_t) == 8 while sizeof(size_t) == 4.
This implies that we are able to access and work on files whose
maximum length is around 2^63-1 bytes, but we can only malloc or
mmap somewhat less than 2^32-1 bytes of memory.

On such a system an implicit conversion of off_t to size_t can cause
the size_t to wrap, resulting in unexpected and exciting behavior.
Right now we are working around all gcc warnings generated by the
-Wshorten-64-to-32 option by passing the off_t through xsize_t().

In the future we should make xsize_t on such problematic platforms
detect the wrapping and die if such a file is accessed.
Signed-off-by: NShawn O. Pearce <spearce@spearce.org>
Signed-off-by: NJunio C Hamano <junkio@cox.net>