thodg/libgit2/src/odb_pack.c

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src/odb_pack.c

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Log

Author	Commit	Date	CI	Message
	0c7f49dd	2017-06-30T13:39:01		Make sure to always include "common.h" first Next to including several files, our "common.h" header also declares various macros which are then used throughout the project. As such, we have to make sure to always include this file first in all implementation files. Otherwise, we might encounter problems or even silent behavioural differences due to macros or defines not being defined as they should be. So in fact, our header and implementation files should make sure to always include "common.h" first. This commit does so by establishing a common include pattern. Header files inside of "src" will now always include "common.h" as its first other file, separated by a newline from all the other includes to make it stand out as special. There are two cases for the implementation files. If they do have a matching header file, they will always include this one first, leading to "common.h" being transitively included as first file. If they do not have a matching header file, they instead include "common.h" as first file themselves. This fixes the outlined problems and will become our standard practice for header and source files inside of the "src/" from now on.
	8d452448	2017-03-20T09:34:59		odb_pack: initialize `git_rawobj` structure The `pack_entry_find_prefix` function receives a `git_rawobj` structure as argument. While the function first initializes the structure to a sensible state, Coverity is unable to correctly detect this, resulting in a warning. Fix this warning by initializing the object to all-zeroes before passing it to the function.
	27051d4e	2016-07-22T13:34:19		odb: only freshen pack files every 2 seconds Since writing multiple objects may all already exist in a single packfile, avoid freshening that packfile repeatedly in a tight loop. Instead, only freshen pack files every 2 seconds.
	8f09a98e	2016-07-14T16:23:24		odb: freshen existing objects when writing When writing an object, we calculate its OID and see if it exists in the object database. If it does, we need to freshen the file that contains it.
	2381d9e4	2016-08-03T17:01:48		mwindow: init mwindow files in git_libgit2_init
	6a2d2f8a	2015-06-17T06:42:20		delta: move delta application to delta.c Move the delta application functions into `delta.c`, next to the similar delta creation functions. Make the `git__delta_apply` functions adhere to other naming and parameter style within the library.
	e10144ae	2016-03-04T01:18:30		odb: improved not found error messages When looking up an abbreviated oid, show the actual (abbreviated) oid the caller passed instead of a full (but ambiguously truncated) oid.
	43820f20	2015-10-14T19:24:07		odb: Be smarter when refreshing backends In the current implementation of ODB backends, each backend is tasked with refreshing itself after a failed lookup. This is standard Git behavior: we want to e.g. reload the packfiles on disk in case they have changed and that's the reason we can't find the object we're looking for. This behavior, however, becomes pathological in repositories where multiple alternates have been loaded. Given that each alternate counts as a separate backend, a miss in the main repository (which can potentially be very frequent in cases where object storage comes from the alternate) will result in refreshing all its packfiles before we move on to the alternate backend where the object will most likely be found. To fix this, the code in `odb.c` has been refactored as to perform the refresh of all the backends externally, once we've verified that the object is nowhere to be found. If the refresh is successful, we then perform the lookup sequentially through all the backends, skipping the ones that we know for sure weren't refreshed (because they have no refresh API). The on-disk pack backend has been adjusted accordingly: it no longer performs refreshes internally.
	02980bdc	2015-06-09T16:53:07		Initialize a few variables Coverity complains about the git_rawobj ones because we use a loop in which we keep remembering the old version, and we end up copying our object as the base, so we want to have the data pointer be NULL.
	b3b66c57	2014-06-18T17:13:12		Share packs across repository instances Opening the same repository multiple times will currently open the same file multiple times, as well as map the same region of the file multiple times. This is not necessary, as the packfile data is immutable. Instead of opening and closing packfiles directly, introduce an indirection and allocate packfiles globally. This does mean locking on each packfile open, but we already use this lock for the global mwindow list so it doesn't introduce a new contention point.
	48e60ae7	2014-04-21T11:23:29		Don't redefine the same callback types, their signatures may change
	f5753999	2014-03-04T15:34:23		Add exists_prefix to ODB backend and ODB API
	25e0b157	2013-12-06T15:07:57		Remove converting user error to GIT_EUSER This changes the behavior of callbacks so that the callback error code is not converted into GIT_EUSER and instead we propagate the return value through to the caller. Instead of using the giterr_capture and giterr_restore functions, we now rely on all functions to pass back the return value from a callback. To avoid having a return value with no error message, the user can call the public giterr_set_str or some such function to set an error message. There is a new helper 'giterr_set_callback' that functions can invoke after making a callback which ensures that some error message was set in case the callback did not set one. In places where the sign of the callback return value is meaningful (e.g. positive to skip, negative to abort), only the negative values are returned back to the caller, obviously, since the other values allow for continuing the loop. The hardest parts of this were in the checkout code where positive return values were overloaded as meaningful values for checkout. I fixed this by adding an output parameter to many of the internal checkout functions and removing the overload. This added some code, but it is probably a better implementation. There is some funkiness in the network code where user provided callbacks could be returning a positive or a negative value and we want to rely on that to cancel the loop. There are still a couple places where an user error might get turned into GIT_EUSER there, I think, though none exercised by the tests.
	96869a4e	2013-12-03T16:45:39		Improve GIT_EUSER handling This adds giterr_user_cancel to return GIT_EUSER and clear any error message that is sitting around. As a result of using that in places, we need to be more thorough with capturing errors that happen inside a callback when used internally. To help with that, this also adds giterr_capture and giterr_restore so that when we internally use a foreach-type function that clears errors and converts them to GIT_EUSER, it is easier to restore not just the return value, but the actual error message text.
	1e60e5f4	2013-11-07T12:03:44		Allow callers to set mode on packfile creation
	a6154f21	2013-10-30T15:00:05		indexer: remove the stream infix It was there to keep it apart from the one which read in from a file on disk. This other indexer does not exist anymore, so there is no need for anything other than git_indexer to refer to it. While here, rename _add() function to _append() and _finalize() to _commit(). The former change is cosmetic, while the latter avoids talking about "finalizing", which OO languages use to mean something completely different.
	5c50f22a	2013-10-28T09:25:44		Merge pull request #1891 from libgit2/cmn/fix-thin-packs Add support for thin packs
	0b33fca0	2013-10-02T13:39:35		indexer: fix thin packs When given an ODB from which to read objects, the indexer will attempt to inject the missing bases at the end of the pack and update the header and trailer to reflect the new contents.
	219d3457	2013-10-01T16:12:15		Initial iconv hookup for precomposed unicode This hooks up git_path_direach and git_path_dirload so that they will take a flag indicating if directory entry names should be tested and converted from decomposed unicode to precomposed form. This code will only come into play on the Apple platform and even then, only when certain types of filesystems are used. This involved adding a flag to these functions which involved changing a lot of places in the code. This was an opportunity to do a bit of code cleanup here and there, for example, getting rid of the git_futils_cleanupdir_r function in favor of a simple flag to git_futils_rmdir_r to not remove the top level entry. That ended up adding depth tracking during rmdir_r which led to a safety check for infinite directory recursion. Yay. This hasn't actually been tested on the Mac filesystems where the issue occurs. I still need to get test environment for that.
	d0cd6c42	2013-09-08T18:22:28		path: Make direach() return EUSER on callback error
	b1a6c316	2013-08-30T17:36:00		odb: Move the auto refresh logic to the pack backend Previously, `git_object_read()`, `git_object_read_prefix()` and `git_object_exists()` were implementing an auto refresh logic. When the expected object couldn't be found in any backend, a call to `git_odb_refresh()` was triggered and the lookup was once again performed against all backends. This commit removes this auto-refresh logic from the odb layer and pushes it down into the pack-backend (as it's the only one currently exposing a `refresh()` endpoint).
	9b4ed214	2013-08-30T17:07:41		odb: Code beautification
	d19bcb33	2013-06-06T14:49:14		odb_pack: handle duplicate objects from different packs This is based on 24634c6fd02b2240e4a93fad70a08220f8fb793a. This also corrects an issue with error codes being mixed up with the number of found objects.
	5d2d21e5	2013-04-16T15:00:43		Consolidate packfile allocation further Rename git_packfile_check to git_packfile_alloc since it is now being used more in that capacity. Fix the various places that use it. Consolidate some repeated code in odb_pack.c related to the allocation of a new pack_backend.
	83cc70d9	2013-04-19T12:48:33		Move odb_backend implementors stuff into git2/sys This moves some of the odb_backend stuff that is related to the internals of an odb_backend implementation into include/git2/sys. Some of the stuff related to streaming I left in include/git2 because it seemed like it would be reasonably needed by a normal user who wanted to stream objects into and out of the ODB. Also, I added APIs for traversing the list of backends so that some of the tests would not need to access ODB internals.
	10c06114	2013-03-17T04:46:46		Several warnings detected by static code analyzer fixed Implicit type conversion argument of function to size_t type Suspicious sequence of types castings: size_t -> int -> size_t Consider reviewing the expression of the 'A = B == C' kind. The expression is calculated as following: 'A = (B == C)' Unsigned type is never < 0
	a5f61384	2013-03-15T12:24:20		odb_pack: Unused functions
	96c9b9f0	2013-01-12T18:38:19		indexer: properly free the packfile resources The indexer needs to call the packfile's free function so it takes care of freeing the caches. We still need to close the mwf descriptor manually so we can rename the packfile into its final name on Windows.
	80d647ad	2013-01-11T20:15:06		Revert "pack: packfile_free -> git_packfile_free and use it in the indexers" This reverts commit f289f886cb81bb570bed747053d5ebf8aba6bef7, which makes the tests fail on Windows. Revert until we can figure out a solution.
	f289f886	2013-01-11T17:24:52		pack: packfile_free -> git_packfile_free and use it in the indexers It turns out the indexers have been ignoring the pack's free function and leaking data. Plug that.
	891a4681	2013-01-04T17:42:41		dat errorcode
	4a863c06	2013-01-03T20:36:26		Sane refresh logic All the ODB backends have a specific refresh interface. When reading an object, first we attempt every single backend: if the read fails, then we refresh all the backends and retry the read one more time to see if the object has appeared.
	359fc2d2	2013-01-08T17:07:25		update copyrights
	e05ca13f	2012-12-05T11:47:19		Merge pull request #1115 from ben/struct-versions Version info for public structs
	bfb8bcc1	2012-12-03T10:36:32		odb-pack: resurrect pack_backend__read_header
	55f6f21b	2012-11-29T19:59:18		Deploy versioned git_odb_backend structure
	c3fb7d04	2012-11-27T15:00:49		Make git_odb_foreach_cb take const param This makes the first OID param of the ODB callback a const pointer and also propogates that change all the way to the backends.
	09cc0b92	2012-11-05T11:33:10		create callback to handle packs from fetch, move the indexer to odb_pack
	63409451	2012-09-19T04:55:16		ODB pack: snapshot last_found to avoid race Also removed unnecessary refresh call and fixed some indentation.
	78216495	2012-09-13T20:08:05		Remove mtime checks from ODB packfile backend Now forcing refresh on a foreach, and on missed full-oid or short-oid lookups.
	5bb0dc93	2012-09-13T14:02:46		ODB: re-load packfiles on failed lookup The old method was avoiding re-loading of packfiles by watching the mtime of the pack directory. This causes the ODB to become stale if the directory and packfile are written within the same clock millisecond, as when cloning a fairly small repo. This method tries to find the object in the cached packs, and forces a refresh when that fails. This will cause extra stat'ing on a miss, but speeds up the success case and avoids this race condition.
	3d7617e4	2012-09-14T21:33:50		odb_pack: fix race condition last_found is the last packfile a wanted object was found in. Since last_found is shared among all searching threads, it might changes while we're searching. As suggested by @arrbee, put a copy on the stack to fix the race condition.
	ab8a0402	2012-09-12T14:26:31		odb_pack: try lookup before refreshing packs This reduces the rate of syscalls for the common case of sequences of object reads from the same pack. Best of 5 timings for libgit2_clar before this patch: real 0m5.375s user 0m0.392s sys 0m3.564s After applying this patch: real 0m5.285s user 0m0.356s sys 0m3.544s 0.6% improvement in system time. 9.2% improvement in user time. 1.7% improvement in elapsed time. Confirmed a 0.6% reduction in number of system calls with strace. Expect greater improvement for graph-traversal with large packs.
	f9988d4e	2012-09-04T21:42:00		odb: pass the user's data pointer correctly in foreach
	51e1d808	2012-08-06T12:41:08		Merge remote-tracking branch 'arrbee/tree-walk-fixes' into development Conflicts: src/notes.c src/transports/git.c src/transports/http.c src/transports/local.c tests-clar/odb/foreach.c
	5dca2010	2012-08-03T17:08:01		Update iterators for consistency across library This updates all the `foreach()` type functions across the library that take callbacks from the user to have a consistent behavior. The rules are: * A callback terminates the loop by returning any non-zero value * Once the callback returns non-zero, it will not be called again (i.e. the loop stops all iteration regardless of state) * If the callback returns non-zero, the parent fn returns GIT_EUSER * Although the parent returns GIT_EUSER, no error will be set in the library and `giterr_last()` will return NULL if called. This commit makes those changes across the library and adds tests for most of the iteration APIs to make sure that they follow the above rules.
	e25dda51	2012-08-02T01:38:30		Merge remote-tracking branch 'nulltoken/topic/amd64-compat' into development Conflicts: src/netops.c src/netops.h src/oid.c
	b8457baa	2012-07-24T07:57:58		portability: Improve x86/amd64 compatibility
	507523c3	2012-07-21T16:23:49		odb: allow creating an ODB backend from a packfile index git_odb_backend_one_packfile() allows us to create an ODB backend out of an .idx file.
	521aedad	2012-06-05T14:48:51		odb: add git_odb_foreach() Go through each backend and list every objects that exists in them. This allows fsck-like uses.
	904b67e6	2012-05-18T01:48:50		errors: Rename error codes
	e172cf08	2012-05-18T01:21:06		errors: Rename the generic return codes
	282283ac	2012-05-04T16:46:46		Fix valgrind issues There are three changes here: - correctly propogate error code from failed object lookups - make zlib inflate use our allocators - add OID to notfound error in ODB lookups
	fa6420f7	2012-04-29T21:46:33		buf: deploy git_buf_len()
	44ef8b1b	2012-04-13T13:00:10		Fix warnings on 64-bit windows builds This fixes all the warnings on win64 except those in deps, which come from the regex code.
	0d0fa7c3	2012-03-16T15:56:01		Convert attr, ignore, mwindow, status to new errors Also cleaned up some previously converted code that still had little things to polish.
	e1de726c	2012-03-12T22:55:40		Migrate ODB files to new error handling This migrates odb.c, odb_loose.c, odb_pack.c and pack.c to the new style of error handling. Also got the unix and win32 versions of map.c. There are some minor changes to other files but no others were completely converted. This also contains an update to filebuf so that a zeroed out filebuf will not think that the fd (== 0) is actually open (and inadvertently call close() on fd 0 if cleaned up). Lastly, this was built and tested on win32 and contains a bunch of fixes for the win32 build which was pretty broken.
	1a481123	2012-02-17T00:13:34		error-handling: References Yes, this is error handling solely for `refs.c`, but some of the abstractions leak all ofer the code base.
	854eccbb	2012-02-29T12:04:59		Clean up GIT_UNUSED macros on all platforms It turns out that commit 31e9cfc4cbcaf1b38cdd3dbe3282a8f57e5366a5 did not fix the GIT_USUSED behavior on all platforms. This commit walks through and really cleans things up more thoroughly, getting rid of the unnecessary stuff. To remove the use of some GIT_UNUSED, I ended up adding a couple of new iterators for hashtables that allow you to iterator just over keys or just over values. In making this change, I found a bug in the clar tests (where we were doing *count++ but meant to do (*count)++ to increment the value). I fixed that but then found the test failing because it was not really using an empty repo. So, I took some of the code that I wrote for iterator testing and moved it to clar_helpers.c, then made use of that to make it easier to open fixtures on a per test basis even within a single test file.
	0c3bae62	2012-02-15T16:56:56		zlib: Remove custom `git2/zlib.h` header This is legacy compat stuff for when `deflateBound` is not defined, but we're not embedding zlib and that function is always available. Kill that with fire.
	5e0de328	2012-02-13T17:10:24		Update Copyright header Signed-off-by: schu <schu-github@schulog.org>
	1744fafe	2012-01-17T15:49:47		Move path related functions from fileops to path This takes all of the functions that look up simple data about paths (such as `git_futils_isdir`) and moves them over to path.h (becoming `git_path_isdir`). This leaves fileops.h just with functions that actually manipulate the filesystem or look at the file contents in some way. As part of this, the dir.h header which is really just for win32 support was moved into win32 (with some minor changes).
	97769280	2011-11-30T11:27:15		Use git_buf for path storage instead of stack-based buffers This converts virtually all of the places that allocate GIT_PATH_MAX buffers on the stack for manipulating paths to use git_buf objects instead. The patch is pretty careful not to touch the public API for libgit2, so there are a few places that still use GIT_PATH_MAX. This extends and changes some details of the git_buf implementation to add a couple of extra functions and to make error handling easier. This includes serious alterations to all the path.c functions, and several of the fileops.c ones, too. Also, there are a number of new functions that parallel existing ones except that use a git_buf instead of a stack-based buffer (such as git_config_find_global_r that exists alongsize git_config_find_global). This also modifies the win32 version of p_realpath to allocate whatever buffer size is needed to accommodate the realpath instead of hardcoding a GIT_PATH_MAX limit, but that change needs to be tested still.
	3286c408	2011-10-28T14:51:13		global: Properly use `git__` memory wrappers Ensure that all memory related functions (malloc, calloc, strdup, free, etc) are using their respective `git__` wrappers.
	599297fd	2011-10-03T23:12:43		ignore missing pack file as git does See http://code.google.com/p/tortoisegit/issues/detail?id=862 Signed-off-by: Sven Strickroth <email@cs-ware.de>
	71a4c1f1	2011-09-18T20:07:59		Merge pull request #384 from kiryl/warnings Add more -W flags to CFLAGS
	87d9869f	2011-09-19T03:34:49		Tabify everything There were quite a few places were spaces were being used instead of tabs. Try to catch them all. This should hopefully not break anything. Except for `git blame`. Oh well.
	bb742ede	2011-09-19T01:54:32		Cleanup legal data 1. The license header is technically not valid if it doesn't have a copyright signature. 2. The COPYING file has been updated with the different licenses used in the project. 3. The full GPLv2 header in each file annoys me.
	d568d585	2011-08-30T23:55:22		CMakefile: add -Wmissing-prototypes and fix warnings Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
	932669b8	2011-08-25T14:22:57		Drop STRLEN() macros There is no need in STRLEN macros. Compilers can do this trivial optimization on its own. Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
	f6867e63	2011-08-08T16:56:28		Fix compilation in Windows
	b5b474dd	2011-07-28T11:45:46		Modify the given offset in git_packfile_unpack The callers immediately throw away the offset, so we don't need any logical changes in any of them. This will be useful for the indexer, as it does need to know where the compressed data ends. Signed-off-by: Carlos Martín Nieto <carlos@cmartin.tk>
	a070f152	2011-07-29T01:08:02		Move pack functions to their own file
	7d0cdf82	2011-07-09T02:25:01		Make packfile_unpack_header more generic On the way, store the fd and the size in the mwindow file. Signed-off-by: Carlos Martín Nieto <carlos@cmartin.tk>
	c7c9e183	2011-07-07T10:17:40		Move the pack structs to an internal header
	7bfdb3d2	2011-06-28T20:39:30		Factor out the mmap window code This code is useful for more things than just the packfile handling code. Factor it out so it can be reused. Signed-off-by: Carlos Martín Nieto <carlos@cmartin.tk>
	03cdbab4	2011-07-15T16:44:25		odb_pack: fix cast warnings /home/kas/git/public/libgit2/src/odb_pack.c: In function ‘packfile_sort__cb’: /home/kas/git/public/libgit2/src/odb_pack.c:702:24: warning: cast discards ‘__attribute__((const))’ qualifier from pointer target type [-Wcast-qual] /home/kas/git/public/libgit2/src/odb_pack.c:703:24: warning: cast discards ‘__attribute__((const))’ qualifier from pointer target type [-Wcast-qual] /home/kas/git/public/libgit2/src/odb_pack.c: In function ‘nth_packed_object_offset’: /home/kas/git/public/libgit2/src/odb_pack.c:944:10: warning: cast discards ‘__attribute__((const))’ qualifier from pointer target type [-Wcast-qual] /home/kas/git/public/libgit2/src/odb_pack.c:944:10: warning: cast discards ‘__attribute__((const))’ qualifier from pointer target type [-Wcast-qual] /home/kas/git/public/libgit2/src/odb_pack.c:944:10: warning: cast discards ‘__attribute__((const))’ qualifier from pointer target type [-Wcast-qual] /home/kas/git/public/libgit2/src/odb_pack.c:948:9: warning: cast discards ‘__attribute__((const))’ qualifier from pointer target type [-Wcast-qual] /home/kas/git/public/libgit2/src/odb_pack.c:948:9: warning: cast discards ‘__attribute__((const))’ qualifier from pointer target type [-Wcast-qual] /home/kas/git/public/libgit2/src/odb_pack.c:948:9: warning: cast discards ‘__attribute__((const))’ qualifier from pointer target type [-Wcast-qual] /home/kas/git/public/libgit2/src/odb_pack.c:952:22: warning: cast discards ‘__attribute__((const))’ qualifier from pointer target type [-Wcast-qual] /home/kas/git/public/libgit2/src/odb_pack.c:952:22: warning: cast discards ‘__attribute__((const))’ qualifier from pointer target type [-Wcast-qual] /home/kas/git/public/libgit2/src/odb_pack.c:952:22: warning: cast discards ‘__attribute__((const))’ qualifier from pointer target type [-Wcast-qual] /home/kas/git/public/libgit2/src/odb_pack.c:953:8: warning: cast discards ‘__attribute__((const))’ qualifier from pointer target type [-Wcast-qual] /home/kas/git/public/libgit2/src/odb_pack.c:953:8: warning: cast discards ‘__attribute__((const))’ qualifier from pointer target type [-Wcast-qual] /home/kas/git/public/libgit2/src/odb_pack.c:953:8: warning: cast discards ‘__attribute__((const))’ qualifier from pointer target type [-Wcast-qual] Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
	de18f276	2011-07-07T01:46:20		vector: Timsort all of the things Drop the GLibc implementation of Merge Sort and replace it with Timsort. The algorithm has been tuned to work on arrays of pointers (void **), so there's no longer a need to abstract the byte-width of each element in the array. All the comparison callbacks now take pointers-to-elements, not pointers-to-pointers, so there's now one less level of dereferencing. E.g. int index_cmp(const void *a, const void *b) { - const git_index_entry *entry_a = *(const git_index_entry **)(a); + const git_index_entry *entry_a = (const git_index_entry *)(a); The result is up to a 40% speed-up when sorting vectors. Memory usage remains lineal. A new `bsearch` implementation has been added, whose callback also supplies pointer-to-elements, to uniform the Vector API again.
	2ee318a7	2011-07-05T15:09:17		Small fixes in pack_window_open Check if the window structure has actually been allocated before trying to access it, and don't leak said structure if the map fails. Signed-off-by: Carlos Martín Nieto <cmn@elego.de>
	f79026b4	2011-07-04T11:43:34		fileops: Cleanup Cleaned up the structure of the whole OS-abstraction layer. fileops.c now contains a set of utility methods for file management used by the library. These are abstractions on top of the original POSIX calls. There's a new file called `posix.c` that contains emulations/reimplementations of all the POSIX calls the library uses. These are prefixed with `p_`. There's a specific posix file for each platform (win32 and unix). All the path-related methods have been moved from `utils.c` to `path.c` and have their own prefix.
	932d1baf	2011-06-30T19:52:34		cleanup: remove trailing spaces Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
	cdb6f9bf	2011-06-20T17:34:01		Allocate enough memory for the terminator in commit parsing Also allow space for the null-terminator when allocating the buffer in packfile_unpack_compressed. Up to now, the last newline had served as a terminator, but 858ef372 searches for a double-newline and exposes the problem. Signed-off-by: Carlos Martín Nieto <cmn@elego.de>
	f1d01851	2011-06-16T02:48:48		oid: Uniformize ncmp methods Drop redundant methods. The ncmp method is now public
	fa48608e	2011-06-16T02:36:21		oid: Rename methods Yeah. Finally. Fuck the old names, this ain't POSIX and they don't make any sense at all.
	1b0d92b1	2011-06-06T18:28:11		Merge pull request #238 from pegonma/git_oid_ncmp Better name for git_oid_match
	c09093cc	2011-06-06T10:55:36		Renamed git_oid_match to git_oid_ncmp. As suggested by carlosmn, git_oid_ncmp would probably be a better name than git_oid_match, for it does the same as git_oid_cmp but only up to a certain amount of hex digits.
	393a9f9e	2011-06-06T00:33:23		Fix build errors on MSVC
	7107b599	2011-06-02T01:03:52		odb-pack: More variable declarations
	7b5fe049	2011-06-02T00:47:51		odb-pack: Do not declare variables mid-function
	6c8ca697	2011-05-29T17:57:25		Fixed some error messages related to searching objects from a short oid. Fixed forgot to check that prefix length is greater than minimum prefix length in read_unique_short_oid method from pack backend.
	d0323a5f	2011-06-01T21:25:56		short-oid: Cleanup
	ac2b94ad	2011-05-28T21:24:25		Added a GIT_OID_MINPREFIXLEN constant to define the minimum length allowed for oid prefixes (set to 4, like in git). Consequently updated some object lookup methods and their documentation.
	ecd6fdf1	2011-05-27T18:49:09		Added a read_unique_short_oid method to backends, to make it possible to find objects from sha1 prefixes in the future. Default implementations throw GIT_ENOTIMPLEMENTED for strict prefixes (i.e. length < GIT_OID_HEXSZ).
	dd453c4d	2011-05-27T22:46:41		Added git.git sha1 lookup method to replace simple binary search in pack backend. Implemented find_unique_short_oid for pack backend, based on git sha1 lookup method; finding an object given its full oid is just a particular case of searching the unique object matching an oid prefix (short oid). Added git_odb_read_unique_short_oid, which iterates over all the backends to find and read the unique object matching the given oid prefix. Added a git_object_lookup_short_oid method to find the unique object in the repository matching a given oid prefix : it generalizes git_object_lookup which now does nothing but calls git_object_lookup_short_oid.
	f84d9819	2011-05-23T21:14:58		odb_pack: Reword errors
	267d539f	2011-05-19T13:38:12		odb_pack.c: Move to new error handling mechanism
	273c8bc0	2011-05-01T14:59:11		Merge pull request #147 from nordsturm/fix_pack_backend_leak. Fix memory leak in pack_backend__free
	c7b79af3	2011-05-01T21:31:58		pack-odb: Check `mtime` instead of folder size Do not check the folder's size to detect new packfiles at runtime. This doesn't work on Win32.
	ed6c462c	2011-04-27T17:30:45		Fix memory leak in pack_backend__free
	1d008781	2011-04-23T23:59:38		Fix conversion warning in MSVC