Commit graph

225 commits

Author SHA1 Message Date
Junio C Hamano 6e353a5e5d Merge branch 'cc/bisect-filter'
* cc/bisect-filter: (21 commits)
  rev-list: add "int bisect_show_flags" in "struct rev_list_info"
  rev-list: remove last static vars used in "show_commit"
  list-objects: add "void *data" parameter to show functions
  bisect--helper: string output variables together with "&&"
  rev-list: pass "int flags" as last argument of "show_bisect_vars"
  t6030: test bisecting with paths
  bisect: use "bisect--helper" and remove "filter_skipped" function
  bisect: implement "read_bisect_paths" to read paths in "$GIT_DIR/BISECT_NAMES"
  bisect--helper: implement "git bisect--helper"
  bisect: use the new generic "sha1_pos" function to lookup sha1
  rev-list: call new "filter_skip" function
  patch-ids: use the new generic "sha1_pos" function to lookup sha1
  sha1-lookup: add new "sha1_pos" function to efficiently lookup sha1
  rev-list: pass "revs" to "show_bisect_vars"
  rev-list: make "show_bisect_vars" non static
  rev-list: move code to show bisect vars into its own function
  rev-list: move bisect related code into its own file
  rev-list: make "bisect_list" variable local to "cmd_rev_list"
  refs: add "for_each_ref_in" function to refactor "for_each_*_ref" functions
  quote: add "sq_dequote_to_argv" to put unwrapped args in an argv array
  ...
2009-04-12 16:46:40 -07:00
Junio C Hamano a54c4edc51 Merge branch 'maint'
* maint:
  GIT 1.6.2.3
  State the effect of filter-branch on graft explicitly
  process_{tree,blob}: Remove useless xstrdup calls

Conflicts:
	GIT-VERSION-GEN
2009-04-12 16:01:25 -07:00
Junio C Hamano 1966af8176 Merge branch 'maint-1.6.1' into maint
* maint-1.6.1:
  State the effect of filter-branch on graft explicitly
  process_{tree,blob}: Remove useless xstrdup calls
2009-04-12 15:34:53 -07:00
Junio C Hamano bc69776aa1 Merge branch 'maint-1.6.0' into maint-1.6.1
* maint-1.6.0:
  State the effect of filter-branch on graft explicitly
  process_{tree,blob}: Remove useless xstrdup calls
2009-04-12 15:20:29 -07:00
Linus Torvalds 213152688c process_{tree,blob}: Remove useless xstrdup calls
On Wed, 8 Apr 2009, Björn Steinbrink wrote:
>
> The name of the processed object was duplicated for passing it to
> add_object(), but that already calls path_name, which allocates a new
> string anyway. So the memory allocated by the xstrdup calls just went
> nowhere, leaking memory.

Ack, ack.

There's another easy 5% or so for the built-in object walker: once we've
created the hash from the name, the name isn't interesting any more, and
so something trivial like this can help a bit.

Does it matter? Probably not on its own. But a few more memory saving
tricks and it might all make a difference.

		Linus

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-04-12 14:30:31 -07:00
Dan McGee b6c29915d2 Update delta compression message to be less misleading
In the case of a small repository, pack-objects is smart enough to not
start more threads than necessary. However, the output to the user always
reports the value of the pack.threads configuration and not the real
number of threads to be used.

Signed-off-by: Dan McGee <dpmcgee@gmail.com>
Acked-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-04-11 22:21:59 -07:00
Junio C Hamano c3067cbfb3 Merge branch 'jc/maint-1.6.0-keep-pack' into maint
* jc/maint-1.6.0-keep-pack:
  pack-objects: don't loosen objects available in alternate or kept packs
  t7700: demonstrate repack flaw which may loosen objects unnecessarily
  Remove --kept-pack-only option and associated infrastructure
  pack-objects: only repack or loosen objects residing in "local" packs
  git-repack.sh: don't use --kept-pack-only option to pack-objects
  t7700-repack: add two new tests demonstrating repacking flaws
  is_kept_pack(): final clean-up
  Simplify is_kept_pack()
  Consolidate ignore_packed logic more
  has_sha1_kept_pack(): take "struct rev_info"
  has_sha1_pack(): refactor "pretend these packs do not exist" interface
  git-repack: resist stray environment variable

Conflicts:
	t/t7700-repack.sh
2009-04-08 23:21:10 -07:00
Christian Couder 11c211fa06 list-objects: add "void *data" parameter to show functions
The goal of this patch is to get rid of the "static struct rev_info
revs" static variable in "builtin-rev-list.c".

To do that, we need to pass the revs to the "show_commit" function
in "builtin-rev-list.c" and this in turn means that the
"traverse_commit_list" function in "list-objects.c" must be passed
functions pointers to functions with 2 parameters instead of one.

So we have to change all the callers and all the functions passed
to "traverse_commit_list".

Anyway this makes the code more clean and more generic, so it
should be a good thing in the long run.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-04-07 22:12:38 -07:00
Junio C Hamano 3c91bf6805 Merge branch 'jc/maint-1.6.0-keep-pack'
* jc/maint-1.6.0-keep-pack:
  pack-objects: don't loosen objects available in alternate or kept packs
  t7700: demonstrate repack flaw which may loosen objects unnecessarily
  Remove --kept-pack-only option and associated infrastructure
  pack-objects: only repack or loosen objects residing in "local" packs
  git-repack.sh: don't use --kept-pack-only option to pack-objects
  t7700-repack: add two new tests demonstrating repacking flaws

Conflicts:
	t/t7700-repack.sh
2009-04-01 22:34:19 -07:00
Junio C Hamano 89fbda2425 Merge branch 'maint'
* maint:
  Increase the size of the die/warning buffer to avoid truncation
  close_sha1_file(): make it easier to diagnose errors
  avoid possible overflow in delta size filtering computation
2009-03-24 19:45:57 -07:00
Junio C Hamano b0de555410 Merge branch 'maint-1.6.1' into maint
* maint-1.6.1:
  close_sha1_file(): make it easier to diagnose errors
  avoid possible overflow in delta size filtering computation
2009-03-24 15:31:21 -07:00
Junio C Hamano 2a5643da73 Merge branch 'maint-1.6.0' into maint-1.6.1
* maint-1.6.0:
  close_sha1_file(): make it easier to diagnose errors
  avoid possible overflow in delta size filtering computation
2009-03-24 15:31:15 -07:00
Nicolas Pitre 720fe22d50 avoid possible overflow in delta size filtering computation
On a 32-bit system, the maximum possible size for an object is less than
4GB, while 64-bit systems may cope with larger objects.  Due to this
limitation, variables holding object sizes are using an unsigned long
type (32 bits on 32-bit systems, or 64 bits on 64-bit systems).

When large objects are encountered, and/or people play with large delta
depth values, it is possible for the maximum allowed delta size
computation to overflow, especially on a 32-bit system.  When this
occurs, surviving result bits may represent a value much smaller than
what it is supposed to be, or even zero.  This prevents some objects
from being deltified although they do get deltified when a smaller depth
limit is used.  Fix this by always performing a 64-bit multiplication.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-03-24 14:37:30 -07:00
Junio C Hamano 2990034f1e Merge branch 'jc/maint-1.6.0-pack-directory' into maint-1.6.1
* jc/maint-1.6.0-pack-directory:
  Fix odb_mkstemp() on AIX
  Make sure objects/pack exists before creating a new pack

Conflicts:
	wrapper.c
2009-03-21 22:53:36 -07:00
Brandon Casey 094085e336 pack-objects: don't loosen objects available in alternate or kept packs
If pack-objects is called with the --unpack-unreachable option then it
will unpack (i.e. loosen) all unreferenced objects from local not-kept
packs, including those that also exist in packs residing in an alternate
object database or a locally kept pack.  The only user of this option is
git-repack.

In this case, repack will follow the call to pack-objects with a call to
prune-packed, which will delete these newly loosened objects, making the
act of loosening a waste of time.  The unnecessary loosening can be
avoided by checking whether an object exists in a non-local pack or a
locally kept pack before loosening it.

This fixes the 'local packed unreachable obs that exist in alternate ODB
are not loosened' test in t7700.

Signed-off-by: Brandon Casey <drafnel@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-03-21 21:58:44 -07:00
Brandon Casey 4d6acb7041 Remove --kept-pack-only option and associated infrastructure
This option to pack-objects/rev-list was created to improve the -A and -a
options of repack.  It was found to be lacking in that it did not provide
the ability to differentiate between local and non-local kept packs, and
found to be unnecessary since objects residing in local kept packs can be
filtered out by the --honor-pack-keep option.

Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-03-20 13:32:33 -07:00
Brandon Casey 79bc4c7155 pack-objects: only repack or loosen objects residing in "local" packs
These two features were invented for use by repack when repack will delete
the local packs that have been made redundant.  The packs accessible
through alternates are not deleted by repack, so the objects contained in
them are still accessible after the local packs are deleted.  They do not
need to be repacked into the new pack or loosened.  For the case of
loosening they would immediately be deleted by the subsequent prune-packed
that is called by repack anyway.

This fixes the test
'packed unreachable obs in alternate ODB are not loosened' in t7700.

Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-03-20 13:32:33 -07:00
Junio C Hamano aec813062b Merge branch 'jc/maint-1.6.0-keep-pack'
* jc/maint-1.6.0-keep-pack:
  is_kept_pack(): final clean-up
  Simplify is_kept_pack()
  Consolidate ignore_packed logic more
  has_sha1_kept_pack(): take "struct rev_info"
  has_sha1_pack(): refactor "pretend these packs do not exist" interface
  git-repack: resist stray environment variable
2009-03-11 13:49:56 -07:00
Junio C Hamano 69e020ae00 is_kept_pack(): final clean-up
Now is_kept_pack() is just a member lookup into a structure, we can write
it as such.

Also rewrite the sole caller of has_sha1_kept_pack() to switch on the
criteria the callee uses (namely, revs->kept_pack_only) between calling
has_sha1_kept_pack() and has_sha1_pack(), so that these two callees do not
have to take a pointer to struct rev_info as an argument.

This removes the header file dependency issue temporarily introduced by
the earlier commit, so we revert changes associated to that as well.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-02-28 01:06:06 -08:00
Junio C Hamano 03a9683d22 Simplify is_kept_pack()
This removes --unpacked=<packfile> parameter from the revision parser, and
rewrites its use in git-repack to pass a single --kept-pack-only option
instead.

The new --kept-pack-only option means just that.  When this option is
given, is_kept_pack() that used to say "not on the --unpacked=<packfile>
list" now says "the packfile has corresponding .keep file".

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-02-28 01:06:06 -08:00
Junio C Hamano 386cb77210 Consolidate ignore_packed logic more
This refactors three loops that check if a given packfile is on the
ignore_packed list into a function is_kept_pack().  The function returns
false for a pack on the list, and true for a pack not on the list, because
this list is solely used by "git repack" to pass list of packfiles that do
not have corresponding .keep files, i.e. a packfile not on the list is
"kept".

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-02-28 01:06:06 -08:00
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
Junio C Hamano 141b6b83d7 Merge branch 'lt/maint-wrap-zlib' into maint
* lt/maint-wrap-zlib:
  Wrap inflate and other zlib routines for better error reporting

Conflicts:
	http-push.c
	http-walker.c
	sha1_file.c
2009-02-05 18:01:00 -08:00
Junio C Hamano 36dd939393 Merge branch 'lt/maint-wrap-zlib'
* lt/maint-wrap-zlib:
  Wrap inflate and other zlib routines for better error reporting

Conflicts:
	http-push.c
	http-walker.c
	sha1_file.c
2009-01-21 16:55:17 -08:00
Linus Torvalds 39c68542fc Wrap inflate and other zlib routines for better error reporting
R. Tyler Ballance reported a mysterious transient repository corruption;
after much digging, it turns out that we were not catching and reporting
memory allocation errors from some calls we make to zlib.

This one _just_ wraps things; it doesn't do the "retry on low memory
error" part, at least not yet. It is an independent issue from the
reporting.  Some of the errors are expected and passed back to the caller,
but we die when zlib reports it failed to allocate memory for now.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-01-11 02:13:06 -08:00
Nicolas Pitre bf87489624 pack-objects: don't use too many threads with few objects
If there are few objects to deltify, they might be split amongst threads
so that there is simply no other objects left to delta against within
the same thread.  Let's use the same 2*window treshold as used for the
final load balancing to allow extra threads to be created.

This fixes the benign t5300 test failure.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Tested-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-12-13 18:55:55 -08:00
Nicolas Pitre 43cc2b4266 autodetect number of CPUs by default when using threads
... and display the actual number of threads used when locally
repacking.  A remote server still won't tell you how many threads it
uses during a fetch though.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-12-12 19:47:36 -08:00
Junio C Hamano de0db42278 Merge branch 'maint'
* maint:
  fsck: reduce stack footprint
  make sure packs to be replaced are closed beforehand
2008-12-11 00:36:31 -08:00
Nicolas Pitre c74faea19e make sure packs to be replaced are closed beforehand
Especially on Windows where an opened file cannot be replaced, make
sure pack-objects always close packs it is about to replace. Even on
non Windows systems, this could save potential bad results if ever
objects were to be read from the new pack file using offset from the old
index.

This should fix t5303 on Windows.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Tested-by: Johannes Sixt <j6t@kdbg.org> (MinGW)
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-12-10 17:56:05 -08:00
Junio C Hamano 0fd9d7e66d Merge branch 'bc/maint-keep-pack' into maint
* bc/maint-keep-pack:
  repack: only unpack-unreachable if we are deleting redundant packs
  t7700: test that 'repack -a' packs alternate packed objects
  pack-objects: extend --local to mean ignore non-local loose objects too
  sha1_file.c: split has_loose_object() into local and non-local counterparts
  t7700: demonstrate mishandling of loose objects in an alternate ODB
  builtin-gc.c: use new pack_keep bitfield to detect .keep file existence
  repack: do not fall back to incremental repacking with [-a|-A]
  repack: don't repack local objects in packs with .keep file
  pack-objects: new option --honor-pack-keep
  packed_git: convert pack_local flag into a bitfield and add pack_keep
  t7700: demonstrate mishandling of objects in packs with a .keep file
2008-12-02 23:00:04 -08:00
Junio C Hamano 7b51b77dbc Merge branch 'np/pack-safer'
* np/pack-safer:
  t5303: fix printf format string for portability
  t5303: work around printf breakage in dash
  pack-objects: don't leak pack window reference when splitting packs
  extend test coverage for latest pack corruption resilience improvements
  pack-objects: allow "fixing" a corrupted pack without a full repack
  make find_pack_revindex() aware of the nasty world
  make check_object() resilient to pack corruptions
  make packed_object_info() resilient to pack corruptions
  make unpack_object_header() non fatal
  better validation on delta base object offsets
  close another possibility for propagating pack corruption
2008-11-12 22:26:35 -08:00
Junio C Hamano ecbbfb15a4 Merge branch 'bc/maint-keep-pack'
* bc/maint-keep-pack:
  t7700: test that 'repack -a' packs alternate packed objects
  pack-objects: extend --local to mean ignore non-local loose objects too
  sha1_file.c: split has_loose_object() into local and non-local counterparts
  t7700: demonstrate mishandling of loose objects in an alternate ODB
  builtin-gc.c: use new pack_keep bitfield to detect .keep file existence
  repack: do not fall back to incremental repacking with [-a|-A]
  repack: don't repack local objects in packs with .keep file
  pack-objects: new option --honor-pack-keep
  packed_git: convert pack_local flag into a bitfield and add pack_keep
  t7700: demonstrate mishandling of objects in packs with a .keep file
2008-11-12 22:00:43 -08:00
Junio C Hamano 6cd3729eae Merge branch 'maint'
* 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
2008-11-12 15:03:57 -08:00
Nicolas Pitre a1e4760fcf Fix pack.packSizeLimit and --max-pack-size handling
If the limit was sufficiently low, having a single object written
could bust the limit (by design), but caused the remaining allowed
size to go negative for subsequent objects, which for an unsigned
variable is a rather huge limit.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-11-12 14:55:03 -08:00
Brandon Casey daae062595 pack-objects: extend --local to mean ignore non-local loose objects too
With this patch, --local means pack only local objects that are not already
packed.

Additionally, this fixes t7700 testing whether loose objects in an alternate
object database are repacked.

Signed-off-by: Brandon Casey <drafnel@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-11-12 10:29:22 -08:00
Brandon Casey e96fb9b8f9 pack-objects: new option --honor-pack-keep
This adds a new option to pack-objects which will cause it to ignore an
object which appears in a local pack which has a .keep file, even if it
was specified for packing.

This option will be used by the porcelain repack.

Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-11-12 10:28:10 -08:00
Nicolas Pitre 59dd9ed183 pack-objects: don't leak pack window reference when splitting packs
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-11-02 15:22:35 -08:00
Nicolas Pitre 64bd76b1de pack-objects: allow "fixing" a corrupted pack without a full repack
When the pack data to be reused is found to be bad, let's fall back to
full object access through the generic path which has its own strategies
to find alternate object sources in that case.  This allows for "fixing"
a corrupted pack simply by copying either another pack containing the
object(s) found to be bad, or the loose object itself, into the object
store and launch a repack without the need for -f.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-11-02 15:22:35 -08:00
Nicolas Pitre 08698b1e32 make find_pack_revindex() aware of the nasty world
It currently calls die() whenever given offset is not found thinking
that such thing should never happen.  But this offset may come from a
corrupted pack whych _could_ happen and not be found.  Callers should
deal with this possibility gracefully instead.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-11-02 15:22:35 -08:00
Nicolas Pitre 03d660150c make check_object() resilient to pack corruptions
The check_object() function tries to get away with the least amount of
pack access possible when it already has partial information on given
object rather than calling the more costly packed_object_info().

When things don't look right, it should just give up and fall back to
packed_object_info() directly instead of die()'ing.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-11-02 15:22:35 -08:00
Nicolas Pitre 09ded04b7e make unpack_object_header() non fatal
It is possible to have pack corruption in the object header.  Currently
unpack_object_header() simply die() on them instead of letting the caller
deal with that gracefully.

So let's have unpack_object_header() return an error instead, and find
a better name for unpack_object_header_gently() in that context.  All
callers of unpack_object_header() are ready for it.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-11-02 15:22:34 -08:00
Nicolas Pitre d8f325563d better validation on delta base object offsets
In one case, it was possible to have a bad offset equal to 0 effectively
pointing a delta onto itself and crashing git after too many recursions.
In the other cases, a negative offset could result due to off_t being
signed.  Catch those.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-11-02 15:22:34 -08:00
Nicolas Pitre 0e8189e270 close another possibility for propagating pack corruption
Abstract
--------

With index v2 we have a per object CRC to allow quick and safe reuse of
pack data when repacking.  This, however, doesn't currently prevent a
stealth corruption from being propagated into a new pack when _not_
reusing pack data as demonstrated by the modification to t5302 included
here.

The Context
-----------

The Git database is all checksummed with SHA1 hashes.  Any kind of
corruption can be confirmed by verifying this per object hash against
corresponding data.  However this can be costly to perform systematically
and therefore this check is often not performed at run time when
accessing the object database.

First, the loose object format is entirely compressed with zlib which
already provide a CRC verification of its own when inflating data.  Any
disk corruption would be caught already in this case.

Then, packed objects are also compressed with zlib but only for their
actual payload.  The object headers and delta base references are not
deflated for obvious performance reasons, however this leave them
vulnerable to potentially undetected disk corruptions.  Object types
are often validated against the expected type when they're requested,
and deflated size must always match the size recorded in the object header,
so those cases are pretty much covered as well.

Where corruptions could go unnoticed is in the delta base reference.
Of course, in the OBJ_REF_DELTA case,  the odds for a SHA1 reference to
get corrupted so it actually matches the SHA1 of another object with the
same size (the delta header stores the expected size of the base object
to apply against) are virtually zero.  In the OBJ_OFS_DELTA case, the
reference is a pack offset which would have to match the start boundary
of a different base object but still with the same size, and although this
is relatively much more "probable" than in the OBJ_REF_DELTA case, the
probability is also about zero in absolute terms.  Still, the possibility
exists as demonstrated in t5302 and is certainly greater than a SHA1
collision, especially in the OBJ_OFS_DELTA case which is now the default
when repacking.

Again, repacking by reusing existing pack data is OK since the per object
CRC provided by index v2 guards against any such corruptions. What t5302
failed to test is a full repack in such case.

The Solution
------------

As unlikely as this kind of stealth corruption can be in practice, it
certainly isn't acceptable to propagate it into a freshly created pack.
But, because this is so unlikely, we don't want to pay the run time cost
associated with extra validation checks all the time either.  Furthermore,
consequences of such corruption in anything but repacking should be rather
visible, and even if it could be quite unpleasant, it still has far less
severe consequences than actively creating bad packs.

So the best compromize is to check packed object CRC when unpacking
objects, and only during the compression/writing phase of a repack, and
only when not streaming the result.  The cost of this is minimal (less
than 1% CPU time), and visible only with a full repack.

Someone with a stats background could provide an objective evaluation of
this, but I suspect that it's bad RAM that has more potential for data
corruptions at this point, even in those cases where this extra check
is not performed.  Still, it is best to prevent a known hole for
corruption when recreating object data into a new pack.

What about the streamed pack case?  Well, any client receiving a pack
must always consider that pack as untrusty and perform full validation
anyway, hence no such stealth corruption could be propagated to remote
repositoryes already.  It is therefore worthless doing local validation
in that case.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-11-02 15:22:15 -08:00
Junio C Hamano aebd173ffa Merge branch 'maint'
* maint:
  Start 1.6.0.4 cycle
  add instructions on how to send patches to the mailing list with Gmail
  Documentation/gitattributes: Add subsection header for each attribute
  git send-email: avoid leaking directory file descriptors.
  send-pack: do not send out single-level refs such as refs/stash
  fix overlapping memcpy in normalize_absolute_path
  pack-objects: avoid reading uninitalized data
  correct cache_entry allocation

Conflicts:
	RelNotes
2008-11-02 00:15:22 -07:00
Jeff King 421b488a58 pack-objects: avoid reading uninitalized data
In the main loop of find_deltas, we do:

  struct object_entry *entry = *list++;
  ...
  if (!*list_size)
	  ...
	  break

Because we look at and increment *list _before_ the check of
list_size, in the very last iteration of the loop we will
look at uninitialized data, and increment the pointer beyond
one past the end of the allocated space. Since we don't
actually do anything with the data until after the check,
this is not a problem in practice.

But since it technically violates the C standard, and
because it provokes a spurious valgrind warning, let's just
move the initialization of entry to a safe place.

This fixes valgrind errors in t5300, t5301, t5302, t303, and
t9400.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-11-01 23:46:40 -07:00
Brandon Casey 19d4b416f4 Replace xmalloc/memset(0) pairs with xcalloc
Many call sites immediately initialize allocated memory with zero after
calling xmalloc. A single call to xcalloc can replace this two-call
sequence.

Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2008-10-08 07:30:59 -07:00
Junio C Hamano c4275591fb Merge branch 'maint'
* maint:
  builtin-prune.c: prune temporary packs in <object_dir>/pack directory
  Do not perform cross-directory renames when creating packs
2008-09-23 02:05:35 -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
Junio C Hamano c4398286fa Merge branch 'np/pack'
* np/pack:
  t5300: improve SHA1 collision test
  pack-objects: don't include missing preferred base objects
  sha1write: don't copy full sized buffers

Conflicts:
	t/t5300-pack-object.sh
2008-09-18 20:19:30 -07:00