Below is oprofile output from GIT command 'git chekcout -q my-v2.6.25'
(move from tag v2.6.27 to tag v2.6.25 of the Linux kernel):
CPU: Core 2, speed 1999.95 MHz (estimated)
Counted CPU_CLK_UNHALTED events (Clock cycles when not halted) with a unit
mask of 0x00 (Unhalted core cycles) count 20000
Counted INST_RETIRED_ANY_P events (number of instructions retired) with a
unit mask of 0x00 (No unit mask) count 20000
CPU_CLK_UNHALT...|INST_RETIRED:2...|
samples| %| samples| %|
------------------------------------
409247 100.000 342878 100.000 git
CPU_CLK_UNHALT...|INST_RETIRED:2...|
samples| %| samples| %|
------------------------------------
260476 63.6476 257843 75.1996 libz.so.1.2.3
100876 24.6492 64378 18.7758 kernel-2.6.28.4_2.vmlinux
30850 7.5382 7874 2.2964 libc-2.9.so
14775 3.6103 8390 2.4469 git
2020 0.4936 4325 1.2614 libcrypto.so.0.9.8
191 0.0467 32 0.0093 libpthread-2.9.so
58 0.0142 36 0.0105 ld-2.9.so
1 2.4e-04 0 0 libldap-2.3.so.0.2.31
Detail list of the top 20 function entries (libz counted in one blob):
CPU_CLK_UNHALTED INST_RETIRED_ANY_P
samples % samples % image name symbol name
260476 63.6862 257843 75.2725 libz.so.1.2.3 /lib/libz.so.1.2.3
16587 4.0555 3636 1.0615 libc-2.9.so memcpy
7710 1.8851 277 0.0809 libc-2.9.so memmove
3679 0.8995 1108 0.3235 kernel-2.6.28.4_2.vmlinux d_validate
3546 0.8670 2607 0.7611 kernel-2.6.28.4_2.vmlinux __getblk
3174 0.7760 1813 0.5293 libc-2.9.so _int_malloc
2396 0.5858 3681 1.0746 kernel-2.6.28.4_2.vmlinux copy_to_user
2270 0.5550 2528 0.7380 kernel-2.6.28.4_2.vmlinux __link_path_walk
2205 0.5391 1797 0.5246 kernel-2.6.28.4_2.vmlinux ext4_mark_iloc_dirty
2103 0.5142 1203 0.3512 kernel-2.6.28.4_2.vmlinux find_first_zero_bit
2077 0.5078 997 0.2911 kernel-2.6.28.4_2.vmlinux do_get_write_access
2070 0.5061 514 0.1501 git cache_name_compare
2043 0.4995 1501 0.4382 kernel-2.6.28.4_2.vmlinux rcu_irq_exit
2022 0.4944 1732 0.5056 kernel-2.6.28.4_2.vmlinux __ext4_get_inode_loc
2020 0.4939 4325 1.2626 libcrypto.so.0.9.8 /usr/lib/libcrypto.so.0.9.8
1965 0.4804 1384 0.4040 git patch_delta
1708 0.4176 984 0.2873 kernel-2.6.28.4_2.vmlinux rcu_sched_grace_period
1682 0.4112 727 0.2122 kernel-2.6.28.4_2.vmlinux sysfs_slab_alias
1659 0.4056 290 0.0847 git find_pack_entry_one
1480 0.3619 1307 0.3816 kernel-2.6.28.4_2.vmlinux ext4_writepage_trans_blocks
Notice the memmove line, where the CPU did 7710 / 277 = 27.8 cycles
per instruction, and compared to the total cycles spent inside the
source code of GIT for this command, all the memmove() calls
translates to (7710 * 100) / 14775 = 52.2% of this.
Retesting with a GIT program compiled for gcov usage, I found out that
the memmove() calls came from remove_index_entry_at() in read-cache.c,
where we have:
memmove(istate->cache + pos,
istate->cache + pos + 1,
(istate->cache_nr - pos) * sizeof(struct cache_entry *));
remove_index_entry_at() is called 4902 times from check_updates() in
unpack-trees.c, and each time called we move each cache_entry pointers
(from the removed one) one step to the left.
Since we have 28828 entries in the cache this time, and if we on
average move half of them each time, we in total move approximately
4902 * 0.5 * 28828 * 4 = 282 629 712 bytes, or twice this amount if
each pointer is 8 bytes (64 bit).
OK, is seems that the function check_updates() is called 28 times, so
the estimated guess above had been more correct if check_updates() had
been called only once, but the point is: we get lots of bytes moved.
To fix this, and use an O(N) algorithm instead, where N is the number
of cache_entries, we delete/remove all entries in one loop through all
entries.
From a retest, the new remove_marked_cache_entries() from the patch
below, ended up with the following output line from oprofile:
46 0.0105 15 0.0041 git remove_marked_cache_entries
If we can trust the numbers from oprofile in this case, we saved
approximately ((7710 - 46) * 20000) / (2 * 1000 * 1000 * 1000) = 0.077
seconds CPU time with this fix for this particular test. And notice
that now the CPU did only 46 / 15 = 3.1 cycles/instruction.
Signed-off-by: Kjetil Barvik <barvik@broadpark.no>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
After you resolve a conflicted merge to remove the path, "git add -u"
failed to record the removal. Instead it errored out by saying that the
removed path is not found in the work tree, but that is what the user
already knows, and the wanted to record the removal as the resolution,
so the error does not make sense.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This simplifies the code, and also makes ce_compare_link now able to
handle filesystems with odd 'st_size' return values for symlinks.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Writing a tree out of an index with an "intent to add" entry is blocked.
This implies that you cannot "git commit" from such a state; however you
can still do "git commit -a" or "git commit $that_path".
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This uses the extended index flag mechanism introduced earlier to mark
the entries added to the index via "git add -N" with CE_INTENT_TO_ADD.
The logic to detect an "intent to add" entry for the purpose of allowing
"git rm --cached $path" is tightened to check not just for a staged empty
blob, but with the CE_INTENT_TO_ADD bit. This protects an empty blob that
was explicitly added and then modified in the work tree from being dropped
with this sequence:
$ >empty
$ git add empty
$ echo "non empty" >empty
$ git rm --cached empty
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* maint:
Start 1.6.0.5 cycle
Fix pack.packSizeLimit and --max-pack-size handling
checkout: Fix "initial checkout" detection
Remove the period after the git-check-attr summary
Conflicts:
RelNotes
Earlier commit 5521883 (checkout: do not lose staged removal, 2008-09-07)
tightened the rule to prevent switching branches from losing local
changes, so that staged removal of paths can be protected, while
attempting to keep a loophole to still allow a special case of switching
out of an un-checked-out state.
However, the loophole was made a bit too tight, and did not allow
switching from one branch (in an un-checked-out state) to check out
another branch.
The change to builtin-checkout.c in this commit loosens it to allow this,
by not insisting the original commit and the new commit to be the same.
It also introduces a new function, is_index_unborn (and an associated
macro, is_cache_unborn), to check if the repository is truly in an
un-checked-out state more reliably, by making sure that $GIT_INDEX_FILE
did not exist when populating the in-core index structure. A few places
the earlier commit 5521883 added the check for the initial checkout
condition are updated to use this function.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If a file is different between the working tree copy, the index, and the
HEAD, then we do not allow it to be deleted without --force.
However, this is overly tight in the face of "git add --intent-to-add":
$ git add --intent-to-add file
$ : oops, I don't actually want to stage that yet
$ git rm --cached file
error: 'empty' has staged content different from both the
file and the HEAD (use -f to force removal)
$ git rm -f --cached file
Unfortunately, there is currently no way to distinguish between an empty
file that has been added and an "intent to add" file. The ideal behavior
would be to disallow the former while allowing the latter.
This patch loosens the safety valve to allow the deletion only if we are
deleting the cached entry and the cached content is empty. This covers
the intent-to-add situation, and assumes there is little harm in not
protecting users who have legitimately added an empty file. In many
cases, the file will still be empty, in which case the safety valve does
not trigger anyway (since the content remains untouched in the working
tree). Otherwise, we do remove the fact that no content was staged, but
given that the content is by definition empty, it is not terribly
difficult for a user to recreate it.
However, we still document the desired behavior in the form of two
tests. One checks the correct removal of an intent-to-add file. The other
checks that we still disallow removal of empty files, but is marked as
expect_failure to indicate this compromise. If the intent-to-add feature
is ever extended to differentiate between normal empty files and
intent-to-add files, then the safety valve can be re-tightened.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When aborting a failed merge that has brought in a new path using "git
reset --hard" or "git read-tree --reset -u", we used to first forget about
the new path (via read_cache_unmerged) and then matched the working tree
to what is recorded in the index, thus ending up leaving the new path in
the work tree.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the "git status" display code was originally converted
to C, we copied the code from ls-files to discover whether a
pathname returned by read_directory was an "other", or
untracked, file.
Much later, 5698454e updated the code in ls-files to handle
some new cases caused by gitlinks. This left the code in
wt-status.c broken: it would display submodule directories
as untracked directories. Nobody noticed until now, however,
because unless status.showUntrackedFiles was set to "all",
submodule directories were not actually reported by
read_directory. So the bug was only triggered in the
presence of a submodule _and_ this config option.
This patch pulls the ls-files code into a new function,
cache_name_is_other, and uses it in both places. This should
leave the ls-files functionality the same and fix the bug
in status.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The on-disk format of index only saves 16 bit flags, nearly all have
been used. The last bit (CE_EXTENDED) is used to for future extension.
This patch extends index entry format to save more flags in future.
The new entry format will be used when CE_EXTENDED bit is 1.
Because older implementation may not understand CE_EXTENDED bit and
misread the new format, if there is any extended entry in index, index
header version will turn 3, which makes it incompatible for older git.
If there is none, header version will return to 2 again.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Many call sites use strbuf_init(&foo, 0) to initialize local
strbuf variable "foo" which has not been accessed since its
declaration. These can be replaced with a static initialization
using the STRBUF_INIT macro which is just as readable, saves a
function call, and takes up fewer lines.
Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
If verification of path failed, it is always better to print an
error message saying this than relying on the caller function to
print a meaningful error message (especially when the callee already
prints error message for another situation).
Because the callers of add_index_entry_with_check() did not print
any error message, it resulted that the user would not notice the
problem when checkout of an invalid path failed.
Signed-off-by: Dmitry Potapov <dpotapov@gmail.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
On ARM I have the following compilation errors:
CC fast-import.o
In file included from cache.h:8,
from builtin.h:6,
from fast-import.c:142:
arm/sha1.h:14: error: conflicting types for 'SHA_CTX'
/usr/include/openssl/sha.h:105: error: previous declaration of 'SHA_CTX' was here
arm/sha1.h:16: error: conflicting types for 'SHA1_Init'
/usr/include/openssl/sha.h:115: error: previous declaration of 'SHA1_Init' was here
arm/sha1.h:17: error: conflicting types for 'SHA1_Update'
/usr/include/openssl/sha.h:116: error: previous declaration of 'SHA1_Update' was here
arm/sha1.h:18: error: conflicting types for 'SHA1_Final'
/usr/include/openssl/sha.h:117: error: previous declaration of 'SHA1_Final' was here
make: *** [fast-import.o] Error 1
This is because openssl header files are always included in
git-compat-util.h since commit 684ec6c63c whenever NO_OPENSSL is not
set, which somehow brings in <openssl/sha1.h> clashing with the custom
ARM version. Compilation of git is probably broken on PPC too for the
same reason.
Turns out that the only file requiring openssl/ssl.h and openssl/err.h
is imap-send.c. But only moving those problematic includes there
doesn't solve the issue as it also includes cache.h which brings in the
conflicting local SHA1 header file.
As suggested by Jeff King, the best solution is to rename our references
to SHA1 functions and structure to something git specific, and define those
according to the implementation used.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
This adds "--intent-to-add" option to "git add". This is to let the
system know that you will tell it the final contents to be staged later,
iow, just be aware of the presense of the path with the type of the blob
for now. It is implemented by staging an empty blob as the content.
With this sequence:
$ git reset --hard
$ edit newfile
$ git add -N newfile
$ edit newfile oldfile
$ git diff
the diff will show all changes relative to the current commit. Then you
can do:
$ git commit -a ;# commit everything
or
$ git commit oldfile ;# only oldfile, newfile not yet added
to pretend you are working with an index-free system like CVS.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* maint:
unpack_trees(): protect the handcrafted in-core index from read_cache()
git-p4: Fix one-liner in p4_write_pipe function.
Completion: add missing '=' for 'diff --diff-filter'
Fix 'git help help'
unpack_trees() rebuilds the in-core index from scratch by allocating a new
structure and finishing it off by copying the built one to the final
index.
The resulting in-core index is Ok for most use, but read_cache() does not
recognize it as such. The function is meant to be no-op if you already
have loaded the index, until you call discard_cache().
This change the way read_cache() detects an already initialized in-core
index, by introducing an extra bit, and marks the handcrafted in-core
index as initialized, to avoid this problem.
A better fix in the longer term would be to change the read_cache() API so
that it will always discard and re-read from the on-disk index to avoid
confusion. But there are higher level API that have relied on the current
semantics, and they and their users all need to get converted, which is
outside the scope of 'maint' track.
An example of such a higher level API is write_cache_as_tree(), which is
used by git-write-tree as well as later Porcelains like git-merge, revert
and cherry-pick. In the longer term, we should remove read_cache() from
there and add one to cmd_write_tree(); other callers expect that the
in-core index they prepared is what gets written as a tree so no other
change is necessary for this particular codepath.
The original version of this patch marked the index by pointing an
otherwise wasted malloc'ed memory with o->result.alloc, but this version
uses Linus's idea to use a new "initialized" bit, which is conceptually
much cleaner.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We do not have any more bits in the on-disk index flags word, but we would
need to have more in the future. Use the last remaining bits as a signal
to tell us that the index entry we are looking at is an extended one.
Since we do not understand the extended format yet, we will just error out
when we see it.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The ie_modified() function is the workhorse for refresh_cache_entry(),
i.e. checking if an index entry that is stat-dirty actually has changes.
After running quicker check to compare cached stat information with
results from the latest lstat(2) to answer "has modification" early, the
code goes on to check if there really is a change by comparing the staged
data with what is on the filesystem by asking ce_modified_check_fs().
However, this function always said "no change" for any gitlinks that has a
directory at the corresponding path. This made ie_modified() to miss
actual changes in the subproject.
The patch fixes this first by modifying an existing short-circuit logic
before calling the ce_modified_check_fs() function. It knows that for any
filesystem entity to which ie_match_stat() says its data has changed, if
its cached size is nonzero then the contents cannot match, which is a
correct optimization only for blob objects. We teach gitlink objects to
this special case, as we already know that any gitlink that
ie_match_stat() says is modified is indeed modified at this point in the
codepath.
With the above change, we could leave ce_modified_check_fs() broken, but
it also futureproofs the code by teaching it to use ce_compare_gitlink(),
instead of assuming (incorrectly) that any directory is unchanged.
Originally noticed by Alex Riesen on Cygwin.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A new configuration variable 'core.trustctime' is introduced to
allow ignoring st_ctime information when checking if paths
in the working tree has changed, because there are situations where
it produces too much false positives. Like when file system crawlers
keep changing it when scanning and using the ctime for marking scanned
files.
The default is to notice ctime changes.
Signed-off-by: Alex Riesen <raa.lkml@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The rewrite of git-mv from a shell script to a builtin was perhaps
a little too straightforward: the git add and git rm queues were
emulated directly, which resulted in a rather complicated code and
caused an inconsistent behaviour when moving dirty index entries;
git mv would update the entry based on working tree state,
except in case of overwrites, where the new entry would still have
sha1 of the old file.
This patch introduces rename_index_entry_at() into the index toolkit,
which will rename an entry while removing any entries the new entry
might render duplicate. This is then used in git mv instead
of all the file queues, resulting in a major simplification
of the code and an inevitable change in git mv -n output format.
Also the code used to refuse renaming overwriting symlink with a regular
file and vice versa; there is no need for that.
A few new tests have been added to the testsuite to reflect this change.
Signed-off-by: Petr Baudis <pasky@suse.cz>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A private function add_files_to_cache() in builtin-add.c was borrowed by
checkout and commit re-implementors without getting properly refactored to
more library-ish place. This does the refactoring.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git update-index --refresh", "git reset" and "git add --refresh" have
reported paths that have local modifications as "needs update" since the
beginning of git.
Although this is logically correct in that you need to update the index at
that path before you can commit that change, it is now becoming more and
more clear, especially with the continuous push for user friendliness
since 1.5.0 series, that the message is suboptimal. After all, the change
may be something the user might want to get rid of, and "updating" would
be absolutely a wrong thing to do if that is the case.
I prepared two alternatives to solve this. Both aim to reword the message
to more neutral "locally modified".
This patch is a more intrusive variant that changes the message for only
Porcelain commands ("add" and "reset") while keeping the plumbing
"update-index" intact.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
builtin-read-tree has a read_cache_unmerged() which is useful for other
builtins, for example builtin-merge uses it as well. Move it to
read-cache.c to avoid code duplication.
Signed-off-by: Miklos Vajna <vmiklos@frugalware.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We use size=0 as the magic token to say the entry is known to be racily
clean, but a sequence that does:
- update the path with a non-empty blob and write the index;
- update an unrelated path and write the index -- this smudges
the above entry;
- truncate the path to size zero.
would make both the size field for the path in the index and the size on
the filesystem zero. We should not mistake it as a clean index entry.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When a cache entry has been marked as CE_VALID, the user has
promised us that any change in the work tree does not matter.
Just mark the entry as up-to-date, and continue.
Signed-off-by: Marius Storm-Olsen <marius@trolltech.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jc/add-n-u:
Make git add -n and git -u -n output consistent
"git-add -n -u" should not add but just report
Conflicts:
builtin-add.c
builtin-mv.c
cache.h
read-cache.c
* js/ignore-submodule:
Ignore dirty submodule states during rebase and stash
Teach update-index about --ignore-submodules
diff options: Introduce --ignore-submodules
Like with the diff machinery, update-index should sometimes just
ignore submodules (e.g. to determine a clean state before a rebase).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update the programs which used the function (as add_file_to_cache).
Signed-off-by: Alex Riesen <raa.lkml@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The commit sequence used to do
if (file_exists(p->path))
add_file_to_cache(p->path, 0);
where both "file_exists()" and "add_file_to_cache()" needed to do a
lstat() on the path to do their work.
This cuts down 'lstat()' calls for the partial commit case by two
for each path we know about (because we do this twice per path).
Just move the lstat() to the caller instead (that's all that
"file_exists()" really does), and pass the stat information down to the
add_to_cache() function.
This essentially makes 'add_to_index()' the core function that adds a path
to the index, getting the index pointer, the pathname and the stat
information as arguments. There are then shorthand helper functions that
use this core function:
- 'add_to_cache()' is just 'add_to_index()' with the default index
- 'add_file_to_cache/index()' is the same, but does the lstat() call
itself, so you can pass just the pathname if you don't already have the
stat information available.
So old users of the 'add_file_to_xyzzy()' are essentially left unchanged,
and this just exposes the more generic helper function that can take
existing stat information into account.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* py/diff-submodule:
is_racy_timestamp(): do not check timestamp for gitlinks
diff-lib.c: rename check_work_tree_entity()
diff: a submodule not checked out is not modified
Add t7506 to test submodule related functions for git-status
t4027: test diff for submodule with empty directory
* lt/case-insensitive:
Make git-add behave more sensibly in a case-insensitive environment
When adding files to the index, add support for case-independent matches
Make unpack-tree update removed files before any updated files
Make branch merging aware of underlying case-insensitive filsystems
Add 'core.ignorecase' option
Make hash_name_lookup able to do case-independent lookups
Make "index_name_exists()" return the cache_entry it found
Move name hashing functions into a file of its own
Make unpack_trees_options bit flags actual bitfields
Because we do not even check the timestamp to determie if a gitlink
is up to date or not, triggering the racy-timestamp check for gitlinks
does not make sense.
This fixes the recently added test in t7506.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When writing the index out, we need to check the work tree again to see if
an entry whose timestamp indicates that it could be "racily clean", in
order to smudge it if it is stat-clean but with modified contents.
However, we can skip this step for entries marked with CE_UPTODATE,
which are known to be the really clean (i.e. the one we already have
checked when we prepared the index). This will reduce lstat(2) calls
necessary in git-status.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This expands on the previous patch, and allows "git add" to sanely handle
a filename that has changed case, keeping the case in the index constant,
and avoiding aliases.
In particular, if you have an index entry called "File", but the
checked-out tree is case-corrupted and has an entry called "file"
instead, doing a
git add .
(or naming "file" explicitly) will automatically notice that we have an
alias, and will replace the name "file" with the existing index
capitalization (ie "File").
However, if we actually have *both* a file called "File" and one called
"file", and they don't have the same lstat() information (ie we're on a
case-sensitive filesystem but have the "core.ignorecase" flag set), we
will error out if we try to add them both.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This simplifies the matching case of "I already have this file and it is
up-to-date" and makes it do the right thing in the face of
case-insensitive aliases.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It's really totally separate functionality, and if we want to start
doing case-insensitive hash lookups, I'd rather do it when it's
separated out.
It also renames "remove_index_entry()" to "remove_name_hash()", because
that really describes the thing better. It doesn't actually remove the
index entry, that's done by "remove_index_entry_at()", which is something
very different, despite the similarity in names.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is in an effort to make the source index of 'unpack_trees()' as
being const, and thus making the compiler help us verify that we only
access it for reading.
The constification also extended to some of the hashing helpers that get
called indirectly.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This new helper is identical to base_name_compare(), except it compares
conflicting directory/file entries as equal in order to help handling DF
conflicts (thus the name).
Note that while a directory name compares as equal to a regular file
with the new helper, they then individually compare _differently_ to a
filename that has a dot after the basename (because '\0' < '.' < '/').
So a directory called "foo/" will compare equal to a file "foo", even
though "foo.c" will compare after "foo" and before "foo/"
This will be used by routines that want to traverse the git namespace
but then handle conflicting entries together when possible.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* db/checkout: (21 commits)
checkout: error out when index is unmerged even with -m
checkout: show progress when checkout takes long time while switching branches
Add merge-subtree back
checkout: updates to tracking report
builtin-checkout.c: Remove unused prefix arguments in switch_branches path
checkout: work from a subdirectory
checkout: tone down the "forked status" diagnostic messages
Clean up reporting differences on branch switch
builtin-checkout.c: fix possible usage segfault
checkout: notice when the switched branch is behind or forked
Build in checkout
Move code to clean up after a branch change to branch.c
Library function to check for unmerged index entries
Use diff -u instead of diff in t7201
Move create_branch into a library file
Build-in merge-recursive
Add "skip_unmerged" option to unpack_trees.
Discard "deleted" cache entries after using them to update the working tree
Send unpack-trees debugging output to stderr
Add flag to make unpack_trees() not print errors.
...
Conflicts:
Makefile
This makes the name hash removal function (which really just sets the
bit that disables lookups of it) available to external routines, and
makes read_cache_unmerged() use it when it drops an unmerged entry from
the index.
It's renamed to remove_index_entry(), and we drop the (unused) 'istate'
argument.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We handled the case of removing and re-inserting cache entries badly,
which is something that merging commonly needs to do (removing the
different stages, and then re-inserting one of them as the merged
state).
We even had a rather ugly special case for this failure case, where
replace_index_entry() basically turned itself into a no-op if the new
and the old entries were the same, exactly because the hash routines
didn't handle it on their own.
So what this patch does is to not just have the UNHASHED bit, but a
HASHED bit too, and when you insert an entry into the name hash, that
involves:
- clear the UNHASHED bit, because now it's valid again for lookup
(which is really all that UNHASHED meant)
- if we're being lazy, we're done here (but we still want to clear the
UNHASHED bit regardless of lazy mode, since we can become unlazy
later, and so we need the UNHASHED bit to always be set correctly,
even if we never actually insert the entry into the hash list)
- if it was already hashed, we just leave it on the list
- otherwise mark it HASHED and insert it into the list
this all means that unhashing and rehashing a name all just works
automatically. Obviously, you cannot change the name of an entry (that
would be a serious bug), but nothing can validly do that anyway (you'd
have to allocate a new struct cache_entry anyway since the name length
could change), so that's not a new limitation.
The code actually gets simpler in many ways, although the lazy hashing
does mean that there are a few odd cases (ie something can be marked
unhashed even though it was never on the hash in the first place, and
isn't actually marked hashed!).
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This creates a hash index of every single file added to the index.
Right now that hash index isn't actually used for much: I implemented a
"cache_name_exists()" function that uses it to efficiently look up a
filename in the index without having to do the O(logn) binary search,
but quite frankly, that's not why this patch is interesting.
No, the whole and only reason to create the hash of the filenames in the
index is that by modifying the hash function, you can fairly easily do
things like making it always hash equivalent names into the same bucket.
That, in turn, means that suddenly questions like "does this name exist
in the index under an _equivalent_ name?" becomes much much cheaper.
Guiding principles behind this patch:
- it shouldn't be too costly. In fact, my primary goal here was to
actually speed up "git commit" with a fully populated kernel tree, by
being faster at checking whether a file already existed in the index. I
did succeed, but only barely:
Best before:
[torvalds@woody linux]$ time git commit > /dev/null
real 0m0.255s
user 0m0.168s
sys 0m0.088s
Best after:
[torvalds@woody linux]$ time ~/git/git commit > /dev/null
real 0m0.233s
user 0m0.144s
sys 0m0.088s
so some things are actually faster (~8%).
Caveat: that's really the best case. Other things are invariably going
to be slightly slower, since we populate that index cache, and quite
frankly, few things really use it to look things up.
That said, the cost is really quite small. The worst case is probably
doing a "git ls-files", which will do very little except puopulate the
index, and never actually looks anything up in it, just lists it.
Before:
[torvalds@woody linux]$ time git ls-files > /dev/null
real 0m0.016s
user 0m0.016s
sys 0m0.000s
After:
[torvalds@woody linux]$ time ~/git/git ls-files > /dev/null
real 0m0.021s
user 0m0.012s
sys 0m0.008s
and while the thing has really gotten relatively much slower, we're
still talking about something almost unmeasurable (eg 5ms). And that
really should be pretty much the worst case.
So we lose 5ms on one "benchmark", but win 22ms on another. Pick your
poison - this patch has the advantage that it will _likely_ speed up
the cases that are complex and expensive more than it slows down the
cases that are already so fast that nobody cares. But if you look at
relative speedups/slowdowns, it doesn't look so good.
- It should be simple and clean
The code may be a bit subtle (the reasons I do hash removal the way I
do etc), but it re-uses the existing hash.c files, so it really is
fairly small and straightforward apart from a few odd details.
Now, this patch on its own doesn't really do much, but I think it's worth
looking at, if only because if done correctly, the name hashing really can
make an improvement to the whole issue of "do we have a filename that
looks like this in the index already". And at least it gets real testing
by being used even by default (ie there is a real use-case for it even
without any insane filesystems).
NOTE NOTE NOTE! The current hash is a joke. I'm ashamed of it, I'm just
not ashamed of it enough to really care. I took all the numbers out of my
nether regions - I'm sure it's good enough that it works in practice, but
the whole point was that you can make a really much fancier hash that
hashes characters not directly, but by their upper-case value or something
like that, and thus you get a case-insensitive hash, while still keeping
the name and the index itself totally case sensitive.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This moves a common boolean expression into a helper function,
and makes the comparison between filesystem timestamp and index
timestamp done in the function in line with the other places.
st.st_mtime should be casted to (unsigned int) when compared to
an index timestamp ce_mtime.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It is a D/F conflict if you want to add "foo/bar" to the index
when "foo" already exists. Also it is a conflict if you want to
add a file "foo" when "foo/bar" exists.
An exception is when the existing entry is there only to mark "I
used to be here but I am being removed". This is needed for
operations such as "git read-tree -m -u" that update the index
and then reflect the result to the work tree --- we need to
remember what to remove somewhere, and we use the index for
that. In such a case, an existing file "foo" is being removed
and we can create "foo/" directory and hang "bar" underneath it
without any conflict.
We used to use (ce->ce_mode == 0) to mark an entry that is being
removed, but (CE_REMOVE & ce->ce_flags) is used for that purpose
these days. An earlier commit forgot to convert the logic in
the code that checks D/F conflict condition.
The old code knew that "to be removed" entries cannot be at
higher stage and actively checked that condition, but it was an
unnecessary check. This patch removes the extra check as well.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This converts the index explicitly on read and write to its on-disk
format, allowing the in-core format to contain more flags, and be
simpler.
In particular, the in-core format is now host-endian (as opposed to the
on-disk one that is network endian in order to be able to be shared
across machines) and as a result we can dispense with all the
htonl/ntohl on accesses to the cache_entry fields.
This will make it easier to make use of various temporary flags that do
not exist in the on-disk format.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Aside from the lstat(2) done for work tree files, there are
quite many lstat(2) calls in refname dwimming codepath. This
patch is not about reducing them.
* It adds a new ce_flag, CE_UPTODATE, that is meant to mark the
cache entries that record a regular file blob that is up to
date in the work tree. If somebody later walks the index and
wants to see if the work tree has changes, they do not have
to be checked with lstat(2) again.
* fill_stat_cache_info() marks the cache entry it just added
with CE_UPTODATE. This has the effect of marking the paths
we write out of the index and lstat(2) immediately as "no
need to lstat -- we know it is up-to-date", from quite a lot
fo callers:
- git-apply --index
- git-update-index
- git-checkout-index
- git-add (uses add_file_to_index())
- git-commit (ditto)
- git-mv (ditto)
* refresh_cache_ent() also marks the cache entry that are clean
with CE_UPTODATE.
* write_index is changed not to write CE_UPTODATE out to the
index file, because CE_UPTODATE is meant to be transient only
in core. For the same reason, CE_UPDATE is not written to
prevent an accident from happening.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We currently use lower 12-bit (masked with CE_NAMEMASK) in the
ce_flags field to store the length of the name in cache_entry,
without checking the length parameter given to
create_ce_flags(). This can make us store incorrect length.
Currently we are mostly protected by the fact that many
codepaths first copy the path in a variable of size PATH_MAX,
which typically is 4096 that happens to match the limit, but
that feels like a bug waiting to happen. Besides, that would
not allow us to shorten the width of CE_NAMEMASK to use the bits
for new flags.
This redefines the meaning of the name length stored in the
cache_entry. A name that does not fit is represented by storing
CE_NAMEMASK in the field, and the actual length needs to be
computed by actually counting the bytes in the name[] field.
This way, only the unusually long paths need to suffer.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* jc/maint-add-sync-stat:
t2200: test more cases of "add -u"
git-add: make the entry stat-clean after re-adding the same contents
ce_match_stat, run_diff_files: use symbolic constants for readability
Conflicts:
builtin-add.c
Earlier in commit 0781b8a9b2
(add_file_to_index: skip rehashing if the cached stat already
matches), add_file_to_index() were taught not to re-add the path
if it already matches the index.
The change meant well, but was not executed quite right. It
used ie_modified() to see if the file on the work tree is really
different from the index, and skipped adding the contents if the
function says "not modified".
This was wrong. There are three possible comparison results
between the index and the file in the work tree:
- with lstat(2) we _know_ they are different. E.g. if the
length or the owner in the cached stat information is
different from the length we just obtained from lstat(2), we
can tell the file is modified without looking at the actual
contents.
- with lstat(2) we _know_ they are the same. The same length,
the same owner, the same everything (but this has a twist, as
described below).
- we cannot tell from lstat(2) information alone and need to go
to the filesystem to actually compare.
The last case arises from what we call 'racy git' situation,
that can be caused with this sequence:
$ echo hello >file
$ git add file
$ echo aeiou >file ;# the same length
If the second "echo" is done within the same filesystem
timestamp granularity as the first "echo", then the timestamp
recorded by "git add" and the timestamp we get from lstat(2)
will be the same, and we can mistakenly say the file is not
modified. The path is called 'racily clean'. We need to
reliably detect racily clean paths are in fact modified.
To solve this problem, when we write out the index, we mark the
index entry that has the same timestamp as the index file itself
(that is the time from the point of view of the filesystem) to
tell any later code that does the lstat(2) comparison not to
trust the cached stat info, and ie_modified() then actually goes
to the filesystem to compare the contents for such a path.
That's all good, but it should not be used for this "git add"
optimization, as the goal of "git add" is to actually update the
path in the index and make it stat-clean. With the false
optimization, we did _not_ cause any data loss (after all, what
we failed to do was only to update the cached stat information),
but it made the following sequence leave the file stat dirty:
$ echo hello >file
$ git add file
$ echo hello >file ;# the same contents
$ git add file
The solution is not to use ie_modified() which goes to the
filesystem to see if it is really clean, but instead use
ie_match_stat() with "assume racily clean paths are dirty"
option, to force re-adding of such a path.
There was another problem with "git add -u". The codepath
shares the same issue when adding the paths that are found to be
modified, but in addition, it asked "git diff-files" machinery
run_diff_files() function (which is "git diff-files") to list
the paths that are modified. But "git diff-files" machinery
uses the same ie_modified() call so that it does not report
racily clean _and_ actually clean paths as modified, which is
not what we want.
The patch allows the callers of run_diff_files() to pass the
same "assume racily clean paths are dirty" option, and makes
"git-add -u" codepath to use that option, to discover and re-add
racily clean _and_ actually clean paths.
We could further optimize on top of this patch to differentiate
the case where the path really needs re-adding (i.e. the content
of the racily clean entry was indeed different) and the case
where only the cached stat information needs to be refreshed
(i.e. the racily clean entry was actually clean), but I do not
think it is worth it.
This patch applies to maint and all the way up.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
ce_match_stat() can be told:
(1) to ignore CE_VALID bit (used under "assume unchanged" mode)
and perform the stat comparison anyway;
(2) not to perform the contents comparison for racily clean
entries and report mismatch of cached stat information;
using its "option" parameter. Give them symbolic constants.
Similarly, run_diff_files() can be told not to report anything
on removed paths. Also give it a symbolic constant for that.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* maint:
Yet more 1.5.3.5 fixes mentioned in release notes
cvsserver: Use exit 1 instead of die when req_Root fails.
git-blame shouldn't crash if run in an unmerged tree
git-config: print error message if the config file cannot be read
fixing output of non-fast-forward output of post-receive-email
If we are in the middle of resolving a merge conflict there may be
one or more files whose entries in the index represent an unmerged
state (index entries in the higher-order stages).
Attempting to run git-blame on any file in such a working directory
resulted in "fatal: internal error: ce_mode is 0" as we use the magic
marker for an unmerged entry is 0 (set up by things like diff-lib.c's
do_diff_cache() and builtin-read-tree.c's read_tree_unmerged())
and the ce_match_stat_basic() function gets upset about this.
I'm not entirely sure that the whole "ce_mode = 0" case is a good
idea to begin with, and maybe the right thing to do is to remove
that horrid freakish special case, but removing the internal error
seems to be the simplest fix for now.
Linus
[sp: Thanks to Björn Steinbrink for the test case]
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
The function make_cache_entry() is too useful to be hidden away in
merge-recursive. So move it to libgit.a (exposing it via cache.h).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This function cannot fail, make it void. Also make write_one act on a
const char* instead of a char*.
Signed-off-by: Pierre Habouzit <madcoder@debian.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jc/cachetree:
Simplify cache API
git-format-patch --in-reply-to: accept <message@id> with angle brackets
git-add -u: do not barf on type changes
Remove duplicate note about removing commits with git-filter-branch
git-clone: improve error message if curl program is missing or not executable
git.el: Allow the add and remove commands to be applied to ignored files.
git.el: Allow selecting whether to display uptodate/unknown/ignored files.
git.el: Keep the status buffer sorted by filename.
hooks--update: Explicitly check for all zeros for a deleted ref.
Earlier, add_file_to_index() invalidated the path in the cache-tree
but remove_file_from_cache() did not, and the user of the latter
needed to invalidate the entry himself. This led to a few bugs due to
missed invalidate calls already. This patch makes the management of
cache-tree less error prone by making more invalidate calls from lower
level cache API functions.
The rules are:
- If you are going to write the index, you should either maintain
cache_tree correctly.
- If you cannot, alternatively you can remove the entire cache_tree
by calling cache_tree_free() before you call write_cache().
- When you modify the index, cache_tree_invalidate_path() should be
called with the path you are modifying, to discard the entry from
the cache-tree structure.
- The following cache API functions exported from read-cache.c (and
the macro whose names have "cache" instead of "index")
automatically call cache_tree_invalidate_path() for you:
- remove_file_from_index();
- add_file_to_index();
- add_index_entry();
You can modify the index bypassing the above API functions
(e.g. find an existing cache entry from the index and modify it in
place). You need to call cache_tree_invalidate_path() yourself in
such a case.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The function make_cache_entry() is too useful to be hidden away in
merge-recursive. So move it to libgit.a (exposing it via cache.h).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This allows to refresh only a subset of the project files, based on
the specified pathspecs.
Signed-off-by: Alexandre Julliard <julliard@winehq.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The read_tree() function is called only from the call chain to
run "git diff --cached" (this includes the internal call made by
git-runstatus to run_diff_index()). The function vacates stage
without any funky "merge" magic. The caller then goes and
compares stage #1 entries from the tree with stage #0 entries
from the original index.
When adding the cache entries this way, it used the general
purpose add_cache_entry(). This function looks for an existing
entry to replace or if there is none to find where to insert the
new entry, resolves D/F conflict and all the other things.
For the purpose of reading entries into an empty stage, none of
that processing is needed. We can instead append everything and
then sort the result at the end.
This commit changes read_tree() to first make sure that there is
no existing cache entries at specified stage, and if that is the
case, it runs add_cache_entry() with ADD_CACHE_JUST_APPEND flag
(new), and then sort the resulting cache using qsort().
This new flag tells add_cache_entry() to omit all the checks
such as "Does this path already exist? Does adding this path
remove other existing entries because it turns a directory to a
file?" and instead append the given cache entry straight at the
end of the active cache. The caller of course is expected to
sort the resulting cache at the end before using the result.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
An earlier commit 366bfcb6 broke git-add by moving read_cache()
call down, because it wanted the directory walking code to grab
paths that are already in the index. The change serves its
purpose, but introduces a regression because the responsibility
of avoiding unnecessary reindexing by matching the cached stat
is shifted nowhere.
This makes it the job of add_file_to_index() function.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When a merge left unmerged entries, git add failed to pick up the
file mode from the index, when core.filemode == 0. If more than one
unmerged entry is there, the order of stage preference is 2, 1, 3.
Noticed by Johannes Sixt.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This uses "git-apply --whitespace=strip" to fix whitespace errors that have
crept in to our source files over time. There are a few files that need
to have trailing whitespaces (most notably, test vectors). The results
still passes the test, and build result in Documentation/ area is unchanged.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This change 'opens' the code block which maps the index file into
memory, making the code clearer and easier to read.
Signed-off-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This makes all low-level functions defined in read-cache.c to
take an explicit index_state structure as their first parameter,
to specify which index to work on. These functions
traditionally operated on "the_index" and were named foo_cache();
the counterparts this patch introduces are called foo_index().
The traditional foo_cache() functions are made into macros that
give "the_index" to their corresponding foo_index() functions.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This defines a index_state structure and moves index-related
global variables into it. Currently there is one instance of
it, the_index, and everybody accesses it, so there is no code
change.
Signed-off-by: Junio C Hamano <junkio@cox.net>
The code to match up index entries with the filesystem was stupidly
broken. We shouldn't compare the filesystem stat() information with
S_IFDIRLNK, since that's purely a git-internal value, and not what the
filesystem uses (on the filesystem, it's just a regular directory).
Also, don't bother to make the stat() time comparisons etc for DIRLNK
entries in ce_match_stat_basic(), since we do an exact match for these
things, and the hints in the stat data simply doesn't matter.
This fixes "git status" with submodules that haven't been checked out in
the supermodule.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This is the promised cleaned-up version of teaching directory traversal
(ie the "read_directory()" logic) about subprojects. That makes "git add"
understand to add/update subprojects.
It now knows to look at the index file to see if a directory is marked as
a subproject, and use that as information as whether it should be recursed
into or not.
It also generally cleans up the handling of directory entries when
traversing the working tree, by splitting up the decision-making process
into small functions of their own, and adding a fair number of comments.
Finally, it teaches "add_file_to_cache()" that directory names can have
slashes at the end, since the directory traversal adds them to make the
difference between a file and a directory clear (it always did that, but
my previous too-ugly-to-apply subproject patch had a totally different
path for subproject directories and avoided the slash for that case).
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This fixes a total thinko in my original series: subprojects do *not* sort
like directories, because the index is sorted purely by full pathname, and
since a subproject shows up in the index as a normal NUL-terminated
string, it never has the issues with sorting with the '/' at the end.
So if you have a subproject "proj" and a file "proj.c", the subproject
sorts alphabetically before the file in the index (and must thus also sort
that way in a tree object, since trees sort as the index).
In contrast, it you have two files "proj/file" and "proj.c", the "proj.c"
will sort alphabetically before "proj/file" in the index. The index
itself, of course, does not actually contain an entry "proj/", but in the
*tree* that gets written out, the tree entry "proj" will sort after the
file entry "proj.c", which is the only real magic sorting rule.
In other words: the magic sorting rule only affects tree entries, and
*only* affects tree entries that point to other trees (ie are of the type
S_IFDIR).
Anyway, that thinko just means that we should remove the special case to
make S_ISDIRLNK entries sort like S_ISDIR entries. They don't. They sort
like normal files.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This teaches the really fundamental core SHA1 object handling routines
about gitlinks. We can compare trees with gitlinks in them (although we
can not actually generate patches for them yet - just raw git diffs),
and they show up as commits in "git ls-tree".
We also know to compare gitlinks as if they were directories (ie the
normal "sort as trees" rules apply).
[jc: amended a cut&paste error]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
* 'jc/read-tree-df' (early part):
Fix switching to a branch with D/F when current branch has file D.
Fix twoway_merge that passed d/f conflict marker to merged_entry().
Fix read-tree --prefix=dir/.
unpack-trees: get rid of *indpos parameter.
unpack_trees.c: pass unpack_trees_options structure to keep_entry() as well.
add_cache_entry(): removal of file foo does not conflict with foo/bar
This function was not called "add_file_to_cache()" only because
an ancient program, update-cache, used that name as an internal
function name that does something slightly different. Now that
is gone, we can take over the better name.
The plan is to name all functions that operate on the default
index xxx_cache(). Later patches create a variant of them that
take an explicit parameter xxx_index(), and then turn
xxx_cache() functions into macros that use "the_index".
Signed-off-by: Junio C Hamano <junkio@cox.net>
The function refresh_cache() is the only user of cache_errno
that switches its behaviour based on what internal function
refresh_cache_entry() finds; pass the error status back in a
parameter passed down to it, to get rid of the global variable
cache_errno.
Signed-off-by: Junio C Hamano <junkio@cox.net>
This error message should not usually trigger, but the function
make_cache_entry() called by add_cacheinfo() can return early
without calling into refresh_cache_entry() that sets cache_errno.
Also the error message had a wrong function name reported, and
it did not say anything about which path failed either.
Signed-off-by: Junio 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: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
Some file systems that can host git repositories and their working copies
do not support symbolic links. But then if the repository contains a symbolic
link, it is impossible to check out the working copy.
This patch enables partial support of symbolic links so that it is possible
to check out a working copy on such a file system. A new flag
core.symlinks (which is true by default) can be set to false to indicate
that the filesystem does not support symbolic links. In this case, symbolic
links that exist in the trees are checked out as small plain files, and
checking in modifications of these files preserve the symlink property in
the database (as long as an entry exists in the index).
Of course, this does not magically make symbolic links work on such defective
file systems; hence, this solution does not help if the working copy relies
on that an entry is a real symbolic link.
Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at>
Signed-off-by: Junio C Hamano <junkio@cox.net>
We currently have two parallel notation for dealing with object types
in the code: a string and a numerical value. One of them is obviously
redundent, and the most used one requires more stack space and a bunch
of strcmp() all over the place.
This is an initial step for the removal of the version using a char array
found in object reading code paths. The patch is unfortunately large but
there is no sane way to split it in smaller parts without breaking the
system.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
When we do not trust executable bit from lstat(2), we copied
existing ce_mode bits without checking if the filesystem object
is a regular file (which is the only thing we apply the "trust
executable bit" business) nor if the blob in the index is a
regular file (otherwise, we should do the same as registering a
new regular file, which is to default non-executable).
Noticed by Johannes Sixt.
Signed-off-by: Junio C Hamano <junkio@cox.net>
