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2009-01-21Merge branch 'lt/maint-wrap-zlib'Libravatar Junio C Hamano1-3/+3
* lt/maint-wrap-zlib: Wrap inflate and other zlib routines for better error reporting Conflicts: http-push.c http-walker.c sha1_file.c
2009-01-11Wrap inflate and other zlib routines for better error reportingLibravatar Linus Torvalds1-3/+3
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>
2008-12-13pack-objects: don't use too many threads with few objectsLibravatar Nicolas Pitre1-0/+4
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>
2008-12-12autodetect number of CPUs by default when using threadsLibravatar Nicolas Pitre1-1/+4
... 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>
2008-12-11Merge branch 'maint'Libravatar Junio C Hamano1-0/+1
* maint: fsck: reduce stack footprint make sure packs to be replaced are closed beforehand
2008-12-10make sure packs to be replaced are closed beforehandLibravatar Nicolas Pitre1-0/+1
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>
2008-12-02Merge branch 'bc/maint-keep-pack' into maintLibravatar Junio C Hamano1-0/+10
* 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
2008-11-12Merge branch 'np/pack-safer'Libravatar Junio C Hamano1-19/+58
* 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
2008-11-12Merge branch 'bc/maint-keep-pack'Libravatar Junio C Hamano1-0/+10
* 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
2008-11-12Merge branch 'maint'Libravatar Junio C Hamano1-2/+10
* 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
2008-11-12Fix pack.packSizeLimit and --max-pack-size handlingLibravatar Nicolas Pitre1-2/+10
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>
2008-11-12pack-objects: extend --local to mean ignore non-local loose objects tooLibravatar Brandon Casey1-0/+3
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>
2008-11-12pack-objects: new option --honor-pack-keepLibravatar Brandon Casey1-0/+7
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>
2008-11-02pack-objects: don't leak pack window reference when splitting packsLibravatar Nicolas Pitre1-3/+9
Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-11-02pack-objects: allow "fixing" a corrupted pack without a full repackLibravatar Nicolas Pitre1-9/+19
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>
2008-11-02make find_pack_revindex() aware of the nasty worldLibravatar Nicolas Pitre1-0/+2
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>
2008-11-02make check_object() resilient to pack corruptionsLibravatar Nicolas Pitre1-6/+17
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>
2008-11-02make unpack_object_header() non fatalLibravatar Nicolas Pitre1-1/+1
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>
2008-11-02better validation on delta base object offsetsLibravatar Nicolas Pitre1-2/+2
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>
2008-11-02close another possibility for propagating pack corruptionLibravatar Nicolas Pitre1-0/+10
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>
2008-11-02Merge branch 'maint'Libravatar Junio C Hamano1-1/+2
* 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
2008-11-01pack-objects: avoid reading uninitalized dataLibravatar Jeff King1-1/+2
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>
2008-10-08Replace xmalloc/memset(0) pairs with xcallocLibravatar Brandon Casey1-3/+1
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>
2008-09-23Merge branch 'maint'Libravatar Junio C Hamano1-1/+1
* maint: builtin-prune.c: prune temporary packs in <object_dir>/pack directory Do not perform cross-directory renames when creating packs
2008-09-22Do not perform cross-directory renames when creating packsLibravatar Petr Baudis1-1/+1
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>
2008-09-18Merge branch 'np/pack'Libravatar Junio C Hamano1-0/+8
* 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
2008-09-15Start conforming code to "git subcmd" style part 3Libravatar Heikki Orsila1-2/+2
User notifications are presented as 'git cmd', and code comments are presented as '"cmd"' or 'git's cmd', rather than 'git-cmd'. Signed-off-by: Heikki Orsila <heikki.orsila@iki.fi> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-09-10Merge branch 'np/maint-safer-pack' into maintLibravatar Junio C Hamano1-19/+15
* np/maint-safer-pack: fixup_pack_header_footer(): use nicely aligned buffer sizes index-pack: use fixup_pack_header_footer()'s validation mode pack-objects: use fixup_pack_header_footer()'s validation mode improve reliability of fixup_pack_header_footer() pack-objects: improve returned information from write_one()
2008-09-02pack-objects: don't include missing preferred base objectsLibravatar Nicolas Pitre1-0/+8
This improves commit 6d6f9cddbe a bit by simply not including missing bases in the list of objects to process at all. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-09-02Merge branch 'np/maint-safer-pack' into np/packLibravatar Junio C Hamano1-19/+15
* np/maint-safer-pack: fixup_pack_header_footer(): use nicely aligned buffer sizes index-pack: use fixup_pack_header_footer()'s validation mode pack-objects: use fixup_pack_header_footer()'s validation mode improve reliability of fixup_pack_header_footer() pack-objects: improve returned information from write_one()
2008-08-30Merge branch 'sp/missing-thin-base' into maintLibravatar Junio C Hamano1-4/+11
* sp/missing-thin-base: pack-objects: Allow missing base objects when creating thin packs
2008-08-29pack-objects: use fixup_pack_header_footer()'s validation modeLibravatar Nicolas Pitre1-2/+2
When limiting the pack size, a new header has to be written to the pack and a new SHA1 computed. Make sure that the SHA1 of what is being read back matches the SHA1 of what was written. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-08-29improve reliability of fixup_pack_header_footer()Libravatar Nicolas Pitre1-1/+2
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>
2008-08-29pack-objects: improve returned information from write_one()Libravatar Nicolas Pitre1-17/+12
This function returns 0 when the current object couldn't be written due to the pack size limit, otherwise the current offset in the pack. There is a problem with this approach however, since current object could be a delta and its delta base might just have been written in the same write_one() call, but those successfully written objects are not accounted in the offset variable tracked by the caller. Currently this is not an issue but a subsequent patch will need this. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-08-27index-pack: be careful after fixing up the header/footerLibravatar Linus Torvalds1-1/+0
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>
2008-08-12pack-objects: Allow missing base objects when creating thin packsLibravatar Shawn O. Pearce1-4/+11
If we are building a thin pack and one of the base objects we would consider for deltification is missing its OK, the other side already has that base object. We may be able to get a delta from another object, or we can simply send the new object whole (no delta). This change allows a shallow clone to store only the objects which are unique to it, as well as the boundary commit and its trees, but avoids storing the boundary blobs. This special form of a shallow clone is able to represent just the difference between two trees. Pack objects change suggested by Nicolas Pitre. Signed-off-by: Shawn O. Pearce <spearce@spearce.org> Acked-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-07-05Fix some warnings (on cygwin) to allow -WerrorLibravatar Ramsay Jones1-5/+10
When printing valuds of type uint32_t, we should use PRIu32, and should not assume that it is unsigned int. On 32-bit platforms, it could be defined as unsigned long. The same caution applies to ntohl(). Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-06-24verify-pack: check packed object CRC when using index version 2Libravatar Nicolas Pitre1-22/+0
To do so, check_pack_crc() moved from builtin-pack-objects.c to pack-check.c where it is more logical to share. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-06-23call init_pack_revindex() lazilyLibravatar Nicolas Pitre1-2/+0
This makes life much easier for next patch, as well as being more efficient when the revindex is actually not used. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-31Remove now unnecessary 'sync()' callsLibravatar Linus Torvalds1-3/+4
Since the pack-files are now always created stably on disk, there is no need to sync() before pruning lose objects or old stale pack-files. [jc: with Nico's clean-up] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-31Make pack creation always fsync() the resultLibravatar Linus Torvalds1-1/+3
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>
2008-05-25Merge branch 'js/config-cb'Libravatar Junio C Hamano1-3/+3
* js/config-cb: Provide git_config with a callback-data parameter Conflicts: builtin-add.c builtin-cat-file.c
2008-05-23Merge branch 'bc/repack'Libravatar Junio C Hamano1-2/+38
* bc/repack: Documentation/git-repack.txt: document new -A behaviour let pack-objects do the writing of unreachable objects as loose objects add a force_object_loose() function builtin-gc.c: deprecate --prune, it now really has no effect git-gc: always use -A when manually repacking repack: modify behavior of -A option to leave unreferenced objects unpacked Conflicts: builtin-pack-objects.c
2008-05-14Provide git_config with a callback-data parameterLibravatar Johannes Schindelin1-3/+3
git_config() only had a function parameter, but no callback data parameter. This assumes that all callback functions only modify global variables. With this patch, every callback gets a void * parameter, and it is hoped that this will help the libification effort. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-13let pack-objects do the writing of unreachable objects as loose objectsLibravatar Nicolas Pitre1-2/+38
Commit ccc1297226b184c40459e9d373cc9eebfb7bd898 changed the behavior of 'git repack -A' so unreachable objects are stored as loose objects. However it did so in a naive and inn efficient way by making packs about to be deleted inaccessible and feeding their content through 'git unpack-objects'. While this works, there are major flaws with this approach: - It is unacceptably sloooooooooooooow. In the Linux kernel repository with no actual unreachable objects, doing 'git repack -A -d' before: real 2m33.220s user 2m21.675s sys 0m3.510s And with this change: real 0m36.849s user 0m24.365s sys 0m1.950s For reference, here's the timing for 'git repack -a -d': real 0m35.816s user 0m22.571s sys 0m2.011s This is explained by the fact that 'git unpack-objects' was used to unpack _every_ objects even if (almost) 100% of them were thrown away. - There is a black out period. Between the removal of the .idx file for the redundant pack and the completion of its unpacking, the unreachable objects become completely unaccessible. This is not a big issue as we're talking about unreachable objects, but some consistency is always good. - There is no way to easily set a sensible mtime for the newly created unreachable loose objects. So, while having a command called "pack-objects" to perform object unpacking looks really odd, this is probably the best compromize to be able to solve the above issues in an efficient way. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-03pack-objects: fix early eviction for max depth delta objectsLibravatar Nicolas Pitre1-1/+1
The 'depth' variable doesn't reflect the actual maximum depth used when other objects already depend on the current one. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-03pack-objects: allow for early delta deflatingLibravatar Nicolas Pitre1-1/+36
When the delta data is cached in memory until it is written to a pack file on disk, it is best to compress it right away in find_deltas() for the following reasons: - we have to compress that data anyway; - this allows for caching more deltas with the same cache size limit; - compression is potentially threaded. This last point is especially relevant for SMP run time. For example, repacking the Linux repo on a quad core processor using 4 threads with all default settings produce the following results before this change: real 2m27.929s user 4m36.492s sys 0m3.091s And with this change applied: real 2m13.787s user 4m37.486s sys 0m3.159s So the actual execution time stayed more or less the same but the wall clock time is shorter. This is however not a good thing to do when generating a pack for network transmission. In that case, the network is most likely to throttle the data throughput, so it is best to make find_deltas() faster in order to start writing data ASAP since we can afford spending more time between writes to compress the data at that point. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-03pack-objects: move compression code in a separate functionLibravatar Nicolas Pitre1-24/+29
A later patch will make use of that code too. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-03pack-objects: clean up write_object() a bitLibravatar Nicolas Pitre1-31/+33
... for improved readability. No functional changes. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-03pack-objects: simplify the condition associated with --all-progressLibravatar Nicolas Pitre1-2/+1
Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>