Граф коммитов

36 Коммитов

Автор SHA1 Сообщение Дата
Sun He 5889271114 finish_tmp_packfile():use strbuf for pathname construction
The old version fixes a maximum length on the buffer, which could be a problem
if one is not certain of the length of get_object_directory().
Using strbuf can avoid the protential bug.

Helped-by: Michael Haggerty <mhagger@alum.mit.edu>
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Sun He <sunheehnus@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-03 12:15:10 -08:00
Junio C Hamano 0f9e62e084 Merge branch 'jk/pack-bitmap'
Borrow the bitmap index into packfiles from JGit to speed up
enumeration of objects involved in a commit range without having to
fully traverse the history.

* jk/pack-bitmap: (26 commits)
  ewah: unconditionally ntohll ewah data
  ewah: support platforms that require aligned reads
  read-cache: use get_be32 instead of hand-rolled ntoh_l
  block-sha1: factor out get_be and put_be wrappers
  do not discard revindex when re-preparing packfiles
  pack-bitmap: implement optional name_hash cache
  t/perf: add tests for pack bitmaps
  t: add basic bitmap functionality tests
  count-objects: recognize .bitmap in garbage-checking
  repack: consider bitmaps when performing repacks
  repack: handle optional files created by pack-objects
  repack: turn exts array into array-of-struct
  repack: stop using magic number for ARRAY_SIZE(exts)
  pack-objects: implement bitmap writing
  rev-list: add bitmap mode to speed up object lists
  pack-objects: use bitmaps when packing objects
  pack-objects: split add_object_entry
  pack-bitmap: add support for bitmap indexes
  documentation: add documentation for the bitmap format
  ewah: compressed bitmap implementation
  ...
2014-02-27 14:01:48 -08:00
Junio C Hamano f06a5e607d Merge branch 'jk/sha1write-void'
Code clean-up.

* jk/sha1write-void:
  do not pretend sha1write returns errors
2014-01-10 10:33:09 -08:00
Vicent Marti 7cc8f97108 pack-objects: implement bitmap writing
This commit extends more the functionality of `pack-objects` by allowing
it to write out a `.bitmap` index next to any written packs, together
with the `.idx` index that currently gets written.

If bitmap writing is enabled for a given repository (either by calling
`pack-objects` with the `--write-bitmap-index` flag or by having
`pack.writebitmaps` set to `true` in the config) and pack-objects is
writing a packfile that would normally be indexed (i.e. not piping to
stdout), we will attempt to write the corresponding bitmap index for the
packfile.

Bitmap index writing happens after the packfile and its index has been
successfully written to disk (`finish_tmp_packfile`). The process is
performed in several steps:

    1. `bitmap_writer_set_checksum`: this call stores the partial
       checksum for the packfile being written; the checksum will be
       written in the resulting bitmap index to verify its integrity

    2. `bitmap_writer_build_type_index`: this call uses the array of
       `struct object_entry` that has just been sorted when writing out
       the actual packfile index to disk to generate 4 type-index bitmaps
       (one for each object type).

       These bitmaps have their nth bit set if the given object is of
       the bitmap's type. E.g. the nth bit of the Commits bitmap will be
       1 if the nth object in the packfile index is a commit.

       This is a very cheap operation because the bitmap writing code has
       access to the metadata stored in the `struct object_entry` array,
       and hence the real type for each object in the packfile.

    3. `bitmap_writer_reuse_bitmaps`: if there exists an existing bitmap
       index for one of the packfiles we're trying to repack, this call
       will efficiently rebuild the existing bitmaps so they can be
       reused on the new index. All the existing bitmaps will be stored
       in a `reuse` hash table, and the commit selection phase will
       prioritize these when selecting, as they can be written directly
       to the new index without having to perform a revision walk to
       fill the bitmap. This can greatly speed up the repack of a
       repository that already has bitmaps.

    4. `bitmap_writer_select_commits`: if bitmap writing is enabled for
       a given `pack-objects` run, the sequence of commits generated
       during the Counting Objects phase will be stored in an array.

       We then use that array to build up the list of selected commits.
       Writing a bitmap in the index for each object in the repository
       would be cost-prohibitive, so we use a simple heuristic to pick
       the commits that will be indexed with bitmaps.

       The current heuristics are a simplified version of JGit's
       original implementation. We select a higher density of commits
       depending on their age: the 100 most recent commits are always
       selected, after that we pick 1 commit of each 100, and the gap
       increases as the commits grow older. On top of that, we make sure
       that every single branch that has not been merged (all the tips
       that would be required from a clone) gets their own bitmap, and
       when selecting commits between a gap, we tend to prioritize the
       commit with the most parents.

       Do note that there is no right/wrong way to perform commit
       selection; different selection algorithms will result in
       different commits being selected, but there's no such thing as
       "missing a commit". The bitmap walker algorithm implemented in
       `prepare_bitmap_walk` is able to adapt to missing bitmaps by
       performing manual walks that complete the bitmap: the ideal
       selection algorithm, however, would select the commits that are
       more likely to be used as roots for a walk in the future (e.g.
       the tips of each branch, and so on) to ensure a bitmap for them
       is always available.

    5. `bitmap_writer_build`: this is the computationally expensive part
       of bitmap generation. Based on the list of commits that were
       selected in the previous step, we perform several incremental
       walks to generate the bitmap for each commit.

       The walks begin from the oldest commit, and are built up
       incrementally for each branch. E.g. consider this dag where A, B,
       C, D, E, F are the selected commits, and a, b, c, e are a chunk
       of simplified history that will not receive bitmaps.

            A---a---B--b--C--c--D
                     \
                      E--e--F

       We start by building the bitmap for A, using A as the root for a
       revision walk and marking all the objects that are reachable
       until the walk is over. Once this bitmap is stored, we reuse the
       bitmap walker to perform the walk for B, assuming that once we
       reach A again, the walk will be terminated because A has already
       been SEEN on the previous walk.

       This process is repeated for C, and D, but when we try to
       generate the bitmaps for E, we can reuse neither the current walk
       nor the bitmap we have generated so far.

       What we do now is resetting both the walk and clearing the
       bitmap, and performing the walk from scratch using E as the
       origin. This new walk, however, does not need to be completed.
       Once we hit B, we can lookup the bitmap we have already stored
       for that commit and OR it with the existing bitmap we've composed
       so far, allowing us to limit the walk early.

       After all the bitmaps have been generated, another iteration
       through the list of commits is performed to find the best XOR
       offsets for compression before writing them to disk. Because of
       the incremental nature of these bitmaps, XORing one of them with
       its predecesor results in a minimal "bitmap delta" most of the
       time. We can write this delta to the on-disk bitmap index, and
       then re-compose the original bitmaps by XORing them again when
       loaded.

       This is a phase very similar to pack-object's `find_delta` (using
       bitmaps instead of objects, of course), except the heuristics
       have been greatly simplified: we only check the 10 bitmaps before
       any given one to find best compressing one. This gives good
       results in practice, because there is locality in the ordering of
       the objects (and therefore bitmaps) in the packfile.

     6. `bitmap_writer_finish`: the last step in the process is
	serializing to disk all the bitmap data that has been generated
	in the two previous steps.

	The bitmap is written to a tmp file and then moved atomically to
	its final destination, using the same process as
	`pack-write.c:write_idx_file`.

Signed-off-by: Vicent Marti <tanoku@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-30 12:19:22 -08:00
Jeff King 9af270e8c2 do not pretend sha1write returns errors
The sha1write function returns an int, but it will always be
"0". The failure-prone parts of the function happen in the
"flush" callback, which cannot pass an error back to us. So
we just end up calling die() during the flush.

Let's just drop the return value altogether, as it only
confuses callers into thinking that it might be useful.

Only one call site actually checked the return value. We can
drop that check, since it just led to a die() anyway.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-26 11:50:20 -08:00
Jeff King 1190a1acf8 pack-objects: name pack files after trailer hash
Our current scheme for naming packfiles is to calculate the
sha1 hash of the sorted list of objects contained in the
packfile. This gives us a unique name, so we are reasonably
sure that two packs with the same name will contain the same
objects.

It does not, however, tell us that two such packs have the
exact same bytes. This makes things awkward if we repack the
same set of objects. Due to run-to-run variations, the bytes
may not be identical (e.g., changed zlib or git versions,
different source object reuse due to new packs in the
repository, or even different deltas due to races during a
multi-threaded delta search).

In theory, this could be helpful to a program that cares
that the packfile contains a certain set of objects, but
does not care about the particular representation. In
practice, no part of git makes use of that, and in many
cases it is potentially harmful. For example, if a dumb http
client fetches the .idx file, it must be sure to get the
exact .pack that matches it. Similarly, a partial transfer
of a .pack file cannot be safely resumed, as the actual
bytes may have changed.  This could also affect a local
client which opened the .idx and .pack files, closes the
.pack file (due to memory or file descriptor limits), and
then re-opens a changed packfile.

In all of these cases, git can detect the problem, as we
have the sha1 of the bytes themselves in the pack trailer
(which we verify on transfer), and the .idx file references
the trailer from the matching packfile. But it would be
simpler and more efficient to actually get the correct
bytes, rather than noticing the problem and having to
restart the operation.

This patch simply uses the pack trailer sha1 as the pack
name. It should be similarly unique, but covers the exact
representation of the objects. Other parts of git should not
care, as the pack name is returned by pack-objects and is
essentially opaque.

One test needs to be updated, because it actually corrupts a
pack and expects that re-packing the corrupted bytes will
use the same name. It won't anymore, but we can easily just
use the name that pack-objects hands back.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-05 15:40:11 -08:00
Ævar Arnfjörð Bjarmason ab1900a36e Appease Sun Studio by renaming "tmpfile"
On Solaris the system headers define the "tmpfile" name, which'll
cause Git compiled with Sun Studio 12 Update 1 to whine about us
redefining the name:

    "pack-write.c", line 76: warning: name redefined by pragma redefine_extname declared static: tmpfile     (E_PRAGMA_REDEFINE_STATIC)
    "sha1_file.c", line 2455: warning: name redefined by pragma redefine_extname declared static: tmpfile    (E_PRAGMA_REDEFINE_STATIC)
    "fast-import.c", line 858: warning: name redefined by pragma redefine_extname declared static: tmpfile   (E_PRAGMA_REDEFINE_STATIC)
    "builtin/index-pack.c", line 175: warning: name redefined by pragma redefine_extname declared static: tmpfile    (E_PRAGMA_REDEFINE_STATIC)

Just renaming the "tmpfile" variable to "tmp_file" in the relevant
places is the easiest way to fix this.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-12-21 10:21:04 -08:00
Junio C Hamano 48b303675a Merge branch 'jc/stream-to-pack'
* jc/stream-to-pack:
  bulk-checkin: replace fast-import based implementation
  csum-file: introduce sha1file_checkpoint
  finish_tmp_packfile(): a helper function
  create_tmp_packfile(): a helper function
  write_pack_header(): a helper function

Conflicts:
	pack.h
2011-12-16 22:33:40 -08:00
Junio C Hamano 68be2fea50 receive-pack, fetch-pack: reject bogus pack that records objects twice
When receive-pack & fetch-pack are run and store the pack obtained over
the wire to a local repository, they internally run the index-pack command
with the --strict option. Make sure that we reject incoming packfile that
records objects twice to avoid spreading such a damage.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-11-16 22:05:21 -08:00
Junio C Hamano 0e990530ae finish_tmp_packfile(): a helper function
Factor out a small logic out of the private write_pack_file() function
in builtin/pack-objects.c.

This changes the order of finishing multi-pack generation slightly. The
code used to

 - adjust shared perm of temporary packfile
 - rename temporary packfile to the final name
 - update mtime of the packfile under the final name
 - adjust shared perm of temporary idxfile
 - rename temporary idxfile to the final name

but because the helper does not want to do the mtime thing, the updated
code does that step first and then all the rest.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-28 12:34:09 -07:00
Junio C Hamano cdf9db3c83 create_tmp_packfile(): a helper function
Factor out a small logic out of the private write_pack_file() function
in builtin/pack-objects.c

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-28 11:52:14 -07:00
Junio C Hamano c0ad465725 write_pack_header(): a helper function
Factor out a small logic out of the private write_pack_file() function
in builtin/pack-objects.c

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-28 11:40:48 -07:00
Junio C Hamano 3c9fc074c2 index-pack --verify: read anomalous offsets from v2 idx file
A pack v2 .idx file usually records offset using 64-bit representation
only when the offset does not fit within 31-bit, but you can handcraft
your .idx file to record smaller offset using 64-bit, storing all zero
in the upper 4-byte.  By inspecting the original idx file when running
index-pack --verify, encode such low offsets that do not need to be in
64-bit but are encoded using 64-bit just like the original idx file so
that we can still validate the pack/idx pair by comparing the idx file
recomputed with the original.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-02-27 23:29:03 -08:00
Junio C Hamano fb956c1f44 write_idx_file: need_large_offset() helper function
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-02-27 23:29:03 -08:00
Junio C Hamano e337a04de2 index-pack: --verify
Given an existing .pack file and the .idx file that describes it,
this new mode of operation reads and re-index the packfile and makes
sure the existing .idx file matches the result byte-for-byte.

All the objects in the .pack file are validated during this operation as
well.  Unlike verify-pack, which visits each object described in the .idx
file in the SHA-1 order, index-pack efficiently exploits the delta-chain
to avoid rebuilding the objects that are used as the base of deltified
objects over and over again while validating the objects, resulting in
much quicker verification of the .pack file and its .idx file.

This version however cannot verify a .pack/.idx pair with a handcrafted v2
index that uses 64-bit offset representation for offsets that would fit
within 31-bit. You can create such an .idx file by giving a custom offset
to --index-version option to the command.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-02-27 23:29:03 -08:00
Junio C Hamano ebcfb3791a write_idx_file: introduce a struct to hold idx customization options
Remove two globals, pack_idx_default version and pack_idx_off32_limit,
and place them in a pack_idx_option structure.  Allow callers to pass
it to write_idx_file() as a parameter.

Adjust all callers to the API change.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-02-27 23:29:03 -08:00
Nicolas Pitre f965c525a4 move encode_in_pack_object_header() to a better place
Commit 1b22b6c897 made duplicated versions of encode_header() into a
common version called encode_in_pack_object_header(). There is however
a better location that sha1_file.c for such a function though, as
sha1_file.c contains nothing related to the creation of packs, and
it is quite populated already.

Also the comment that was moved to the header file should really remain
near the function as it covers implementation details and provides no
information about the actual function interface.

Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-02-23 13:10:56 -08:00
Linus Torvalds 3bb7256281 make "index-pack" a built-in
This required some fairly trivial packfile function 'const' cleanup,
since the builtin commands get a const char *argv[] array.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-01-22 10:10:27 -08:00
Thomas Rast d824cbba02 Convert existing die(..., strerror(errno)) to die_errno()
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>
2009-06-27 11:14:53 -07:00
Junio C Hamano bb0cebd7d0 Merge branch 'jc/maint-1.6.0-pack-directory'
* jc/maint-1.6.0-pack-directory:
  Make sure objects/pack exists before creating a new pack
2009-02-25 14:50:05 -08:00
Junio C Hamano 6e180cdcec Make sure objects/pack exists before creating a new pack
In a repository created with git older than f49fb35 (git-init-db: create
"pack" subdirectory under objects, 2005-06-27), objects/pack/ directory is
not created upon initialization.  It was Ok because subdirectories are
created as needed inside directories init-db creates, and back then,
packfiles were recent invention.

After the said commit, new codepaths started relying on the presense of
objects/pack/ directory in the repository.  This was exacerbated with
8b4eb6b (Do not perform cross-directory renames when creating packs,
2008-09-22) that moved the location temporary pack files are created from
objects/ directory to objects/pack/ directory, because moving temporary to
the final location was done carefully with lazy leading directory creation.

Many packfile related operations in such an old repository can fail
mysteriously because of this.

This commit introduces two helper functions to make things work better.

 - odb_mkstemp() is a specialized version of mkstemp() to refactor the
   code and teach it to create leading directories as needed;

 - odb_pack_keep() refactors the code to create a ".keep" file while
   create leading directories as needed.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-02-25 14:39:42 -08:00
Nicolas Pitre 9126f0091f fix openssl headers conflicting with custom SHA1 implementations
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>
2008-10-02 18:06:56 -07:00
Petr Baudis 8b4eb6b6cd Do not perform cross-directory renames when creating packs
A comment on top of create_tmpfile() describes caveats ('can have
problems on various systems (FAT, NFS, Coda)') that should apply
in this situation as well.  This in the end did not end up solving
any of my personal problems, but it might be a useful cleanup patch
nevertheless.

Signed-off-by: Petr Baudis <pasky@suse.cz>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-09-22 12:19:14 -07:00
Nicolas Pitre d35825da6d fixup_pack_header_footer(): use nicely aligned buffer sizes
It should be more efficient to use nicely aligned buffer sizes, either
for filesystem operations or SHA1 checksums.  Also, using a relatively
small nominal size might allow for the data to remain in L1 cache
between both SHA1_Update() calls.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-08-29 21:51:28 -07:00
Nicolas Pitre abeb40e5aa improve reliability of fixup_pack_header_footer()
Currently, this function has the potential to read corrupted pack data
from disk and give it a valid SHA1 checksum.  Let's add the ability to
validate SHA1 checksum of existing data along the way, including before
and after any arbitrary point in the pack.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-08-29 21:51:27 -07:00
Linus Torvalds 0c68d386da index-pack: be careful after fixing up the header/footer
The index-pack command, when processing a thin pack, fixed up the pack
after-the-fact.  It forgets to fsync the result, because it only did that
in one path rather in all cases of fixup.

This moves the fsync_or_die() to the fix-up routine itself, rather than
doing it in one of the callers, so that all cases are covered.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-08-27 13:33:56 -07:00
Nicolas Pitre c0a5e2d477 pack.indexversion config option now defaults to 2
As announced for 1.6.0.

Git older than version 1.5.2 (or any other git version with this option
set to 1) may revert to version 1 of the pack index by manually deleting
all .idx files and recreating them using 'git index-pack'.  Communication
over the git native protocol is unaffected since the pack index is never
transferred.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-06-25 21:30:55 -07:00
Linus Torvalds 4c81b03e30 Make pack creation always fsync() the result
This means that we can depend on packs always being stable on disk,
simplifying a lot of the object serialization worries.  And unlike loose
objects, serializing pack creation IO isn't going to be a performance
killer.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-31 14:46:57 -07:00
Heikki Orsila c697ad143b Cleanup xread() loops to use read_in_full()
Signed-off-by: Heikki Orsila <heikki.orsila@iki.fi>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-03 22:15:25 -07:00
Junio C Hamano 265ae18826 Merge branch 'np/progress'
* np/progress:
  Show total transferred as part of throughput progress
  make sure throughput display gets updated even if progress doesn't move
  return the prune-packed progress display to the inner loop
  add throughput display to git-push
  add some copyright notice to the progress display code
  add throughput display to index-pack
  add throughput to progress display
  relax usage of the progress API
  make struct progress an opaque type
  prune-packed: don't call display_progress() for every file
  Stop displaying "Pack pack-$ID created." during git-gc
  Teach prune-packed to use the standard progress meter
  Change 'Deltifying objects' to 'Compressing objects'
  fix for more minor memory leaks
  fix const issues with some functions
  pack-objects.c: fix some global variable abuse and memory leaks
  pack-objects: no delta possible with only one object in the list
  cope with multiple line breaks within sideband progress messages
  more compact progress display
2007-11-02 16:27:37 -07:00
Nicolas Pitre 4049b9cfc0 fix const issues with some functions
Two functions, namely write_idx_file() and open_pack_file(), currently
return a const pointer.  However that pointer is either a copy of the
first argument, or set to a malloc'd buffer when that first argument
is null.  In the later case it is wrong to qualify that pointer as const
since ownership of the buffer is transferred to the caller to dispose of,
and obviously the free() function is not meant to be passed const
pointers.

Making the return pointer not const causes a warning when the first
argument is returned since that argument is also marked const.

The correct thing to do is therefore to remove the const qualifiers,
avoiding the need for ugly casts only to silence some warnings.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2007-10-17 02:54:57 -04:00
Shawn O. Pearce 106764e651 Refactor index-pack "keep $sha1" handling for reuse
There is a subtle (but important) linkage between receive-pack and
index-pack that allows index-pack to create a packfile but protect
it from being deleted by a concurrent `git repack -a -d` operation.
The linkage works by having index-pack mark the newly created pack
with a ".keep" file and then it passes the SHA-1 name of that new
packfile to receive-pack along its stdout channel.

The receive-pack process must unkeep the packfile by deleting the
.keep file, but can it can only do so after all elgible refs have
been updated in the receiving repository.  This ensures that the
packfile is either kept or its objects are reachable, preventing
a concurrent repacker from deleting the packfile before it can
determine that its objects are actually needed by the repository.

The new builtin-fetch code needs to perform the same actions if
it choose to run index-pack rather than unpack-objects, so I am
moving this code out to its own function where both receive-pack
and fetch-pack are able to invoke it when necessary.  The caller
is responsible for deleting the returned ".keep" and freeing the
path if the returned path is not NULL.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-09-19 03:22:30 -07:00
Luiz Fernando N. Capitulino 7647b17f1d Use xmkstemp() instead of mkstemp()
xmkstemp() performs error checking and prints a standard error message when
an error occur.

Signed-off-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-08-14 22:20:26 -07:00
Geert Bosch aa7e44bf57 Unify write_index_file functions
This patch unifies the write_index_file functions in
builtin-pack-objects.c and index-pack.c.  As the name
"index" is overloaded in git, move in the direction of
using "idx" and "pack idx" when refering to the pack index.
There should be no change in functionality.

Signed-off-by: Geert Bosch <bosch@gnat.com>
Acked-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-06-02 13:14:18 -07:00
Johan Herland 2924415f4f Fix signedness on return value from xread()
The return value from xread() is ssize_t.
Paolo Teti <paolo.teti@gmail.com> pointed out that in this case, the
signed return value was assigned to an unsigned type (size_t). This patch
fixes that.

Signed-off-by: Johan Herland <johan@herland.net>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-05-15 21:15:54 -07:00
Dana L. How 8b0eca7c7b Create pack-write.c for common pack writing code
Include a generalized fixup_pack_header_footer() in this new file.
Needed by git-repack --max-pack-size feature in a later patchset.

[sp: Moved close(pack_fd) to callers, to support index-pack, and
     changed name to better indicate it is for packfiles.]

Signed-off-by: Dana L. How <danahow@gmail.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2007-05-02 13:24:18 -04:00