When defined, this allows plumbing commands that update the
index (add, apply, checkout-index, merge-recursive, mv,
read-tree, rm, update-index, and write-tree) to write their
resulting index to an alternative index file while holding a
lock to the original index file. With this, git-commit that
jumps the index does not have to make an extra copy of the index
file, and more importantly, it can do the update while holding
the lock on the index.
However, I think the interface to let an environment variable
specify the output is a mistake, as shown in the documentation.
If a curious user has the environment variable set to something
other than the file GIT_INDEX_FILE points at, almost everything
will break. This should instead be a command line parameter to
tell these plumbing commands to write the result in the named
file, to prevent stupid mistakes.
Signed-off-by: Junio C Hamano <junkio@cox.net>
It was stupid to link the same element twice to lock_file_list
and end up in a loop, so we certainly need a fix.
But it is not like we are taking a lock on multiple files in
this case. It is just that we leave the linked element on the
list even after commit_lock_file() successfully removes the
cruft.
We cannot remove the list element in commit_lock_file(); if we
are interrupted in the middle of list manipulation, the call to
remove_lock_file_on_signal() will happen with a broken list
structure pointed by lock_file_list, which would cause the cruft
to remain, so not removing the list element is the right thing
to do. Instead we should be reusing the element already on the
list.
There is already a code for that in lock_file() function in
lockfile.c. The code checks lk->next and the element is linked
only when it is not already on the list -- which is incorrect
for the last element on the list (which has NULL in its next
field), but if you read the check as "is this element already on
the list?" it actually makes sense. We do not want to link it
on the list again, nor we would want to set up signal/atexit
over and over.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This is a mechanical clean-up of the way *.c files include
system header files.
(1) sources under compat/, platform sha-1 implementations, and
xdelta code are exempt from the following rules;
(2) the first #include must be "git-compat-util.h" or one of
our own header file that includes it first (e.g. config.h,
builtin.h, pkt-line.h);
(3) system headers that are included in "git-compat-util.h"
need not be included in individual C source files.
(4) "git-compat-util.h" does not have to include subsystem
specific header files (e.g. expat.h).
Signed-off-by: Junio C Hamano <junkio@cox.net>
Most of the callers except the one in refs.c use the function to
update the index file. Among the index writers, everybody
except write-tree dies if they cannot open it for writing.
This gives the function an extra argument, to tell it to die
when it cannot create a new file as the lockfile.
The only caller that does not have to die is write-tree, because
updating the index for the cache-tree part is optional and not
being able to do so does not affect the correctness. I think we
do not have to be so careful and make the failure into die() the
same way as other callers, but that would be a different patch.
Signed-off-by: Junio C Hamano <junkio@cox.net>
There were a few calls to adjust_shared_perm() that were
missing:
- init-db creates refs, refs/heads, and refs/tags before
reading from templates that could specify sharedrepository in
the config file;
- updating config file created it under user's umask without
adjusting;
- updating refs created it under user's umask without
adjusting;
- switching branches created .git/HEAD under user's umask
without adjusting.
This moves adjust_shared_perm() from sha1_file.c to path.c,
since a few SIMPLE_PROGRAM need to call repository configuration
functions which in turn need to call adjust_shared_perm().
sha1_file.c needs to link with SHA1 computation library which
is usually not linked to SIMPLE_PROGRAM.
Signed-off-by: Junio C Hamano <junkio@cox.net>
The framework to create lockfiles that are removed at exit is
first used to reliably write the index file, but it is
applicable to other things, so stop calling it "cache_file".
This also rewords a few remaining error message that called the
index file "cache file".
Signed-off-by: Junio C Hamano <junkio@cox.net>