src/odb.c


Log

Author Commit Date CI Message
Ramsay Jones 54b9460f 2010-04-07T20:13:56 Fix the memory leak caused by failing to free the 'offset index' Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Ramsay Jones 2cdc4544 2010-02-26T22:53:10 Add a pack index 'virtual function' to fetch an index entry Given an index entry number, the idx_get() function returns an (version agnostic) index_entry structure containing all of the information required to unpack the corresponding object from the '.pack' file. Since the v1 and v2 file formats differ in the layout of the object records, we provide two implementations of the get function and initialise the function pointer appropriately. Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Ramsay Jones 608d33fa 2010-02-26T19:59:06 Add a pack index 'virtual function' to search by file offset In addition to searching the index by oid, we need to search by '.pack' file offset, particularly when processing OBJ_OFS_DELTA objects. Since the v1 and v2 file formats differ in the layout of the object records, we provide two implementations of the search function and initialise the (virtual) function pointer appropriately. Note that, as part of the creation of the 'offset index', we also add a check that the offset data in the index is within the bounds of the '.pack' file. Having sorted the file offsets, while creating the index, we only need to check the smallest and largest values. The offset index consists of the im_off_idx array, which contains the index entry numbers sorted into file offset order, and the im_off_next mapping array. The im_off_next array maps an index entry number to the 'next' index entry in file offset order. Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Ramsay Jones abf5681c 2010-02-26T19:29:54 Change the interface of the pack index search function In particular, on a successful search, we now return the index entry number of the object rather than the '.pack' file offset. Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Ramsay Jones 238e54bc 2010-02-21T15:34:53 Add an 64-bit offset table index bounds check for v2 pack index Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Ramsay Jones 255a0dab 2010-02-19T22:36:31 Add a minimum size check when opening an v2 pack index file Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Ramsay Jones 1e5dd572 2010-02-12T16:50:33 Fix some coding style issues Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Ramsay Jones e8a95256 2010-01-04T18:57:13 msvc: Fix some -W4 warnings Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Ramsay Jones 1a7bae4d 2010-01-11T22:51:42 Fix some "unused parameter" warnings with -Wextra Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Ramsay Jones 0ef9d2aa 2010-01-03T22:56:54 Fix some "signed v unsigned comparison" warnings with -Wextra Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Ramsay Jones a4f863af 2010-01-03T19:37:04 Fix an always false comparison "unsigned < 0" warning Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Ramsay Jones 8a086f87 2009-06-14T22:12:20 win32: Add support for the MS Visual C/C++ compiler Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Ramsay Jones 2bf93fa1 2009-06-14T22:10:23 Correct the spelling of the FLEX_ARRAY macro When setting the default value, the macro name was specified as GIT_FLEX_ARRAY, which is inconsistent with it's earlier usage in the file. This caused a compilation error, using the MS Visual C/C++ compiler, when compiling the git_packlist struct definition in src/odb.c. In addition to changing the spelling of the FLEX_ARRAY macro to GIT_FLEX_ARRAY, including it's use in src/odb.c, we also rename the TYPEOF macro to GIT_TYPEOF. Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Ramsay Jones e17a3f56 2009-06-04T16:47:59 Implement git_odb_write() Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk> Signed-off-by: Andreas Ericsson <ae@op5.se>
Ramsay Jones ac04bdf6 2009-06-04T16:44:54 Fix a usage error in a call to the object_file_name() function In 82324ac, the new static function exists_loose() called object_file_name() and, in order to detect an error return, tested for a negative value. This usage is incorrect, as the error return is indicated by a positive return value. (A successful call is indicated by a zero return value) The only error return from object_file_name() relates to insufficient buffer space and the return value gives the required minimum buffer size (which will always be >0). If the caller requires a dynamically allocated buffer, this allows something like the following call sequence: size_t len = object_file_name(NULL, 0, db->object_dir, id); char *buf = git__malloc(len); if (!buf) error(...); object_file_name(buf, len, db->object_dir,id); ... No current callers take advantage of this capability. Fix up the call site and change the return type of the function, from int to size_t, which more accurately reflects the implementation. Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk> Signed-off-by: Andreas Ericsson <ae@op5.se>
Ramsay Jones 79ca2edc 2009-03-20T19:51:48 win32: Add routines to abstract memory-mapped file functions In particular, the git__mmap() and git__munmap() routines provide the interface to platform specific memory-mapped file facilities. We provide implementations for unix and win32, which can be found in their own sub-directories. Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Ramsay Jones 840fb8b7 2009-02-18T18:53:48 win32: fixup some headers to improve win32 compilation Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Ramsay Jones a9984a4e 2009-02-18T18:52:13 Fix some (digital-mars) compiler warnings In particular, conditional expressions which contain an assignment statement, where the expression type is not explicitly made to be boolean, elicits the following message: warning 2: possible unintended assignment Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Ramsay Jones 82324ac1 2009-02-10T21:49:48 Add the git_odb_exists() object query function This function determines if the given object can be found in the object database. At present, only the local object database is searched. Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Ramsay Jones e9f5e877 2009-02-03T18:25:13 Rearrange some code to improve clarity In particular, the test for z-stream input completion (zs.avail_in != 0) logically belongs with the test for the Z_STREAM_END stream status. This is also consistent with the identical check in finish_inflate(). Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Ramsay Jones 236e7579 2009-02-03T18:23:50 Check for error returns from inflateInit() At present, it is sufficient to ensure that an error return from inflateInit() is not ignored. Most error returns, like Z_VERSION_ERROR and Z_STREAM_ERROR, indicate programming or build errors. These errors could, perhaps, be handled with simple asserts. However, for a Z_MEM_ERROR, we may want to perform some further error handling in the future. Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Ramsay Jones c94eb4aa 2009-02-03T18:22:09 Fix a potential memory leak In particular, neglecting to call inflateEnd() along various codepaths in the inflate_tail() routine, would result in the failure to release zlib internal state. Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Shawn O. Pearce bed3229b 2009-01-03T03:34:09 Precompute the fanout decoding and the oid offset in a pack-*.idx The fanout table is fairly commonly accessed, we need to read it twice for each object we lookup in any given pack file. Most of the processors running Git are running in little-endian mode, as they are variants of the x86 platform, so reading the fanout is a costly operation as we need to convert from network byte order to local byte order. By decoding the fanout table into a malloc obtained buffer we can save these 2 decode operations per lookup and make search go more quickly. This also cleans up the initialization of the search functions by cutting out a few instructions, saving a small amount of time. Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Shawn O. Pearce a7c60cfc 2009-01-03T02:41:26 Add basic support to read pack-*.idx v1 and v2 files The index data is mapped into memory and then scanned using a binary search algorithm to locate the matching entry for the supplied git_oid. The standard fanout hash trick is applied to reduce the search space by 8 iterations. Since the v1 and v2 file formats differ in their search function, due to the different layouts used for the object records, we use two different search implementations and a virtual function pointer to jump to the correct version of code for the current pack index. The single function jump per-pack should be faster then computing a branch point inside the inner loop of a common binary search. To improve concurrency during read operations the pack lock is only held while verifying the index is actually open, or while opening the index for the first time. This permits multiple concurrent readers to scan through the same index. If an invalid index file is opened we close it and mark the git_pack's invalid bit to true. The git_pack structure is kept around in its parent git_packlist, but the invalid bit will cause all future readers to skip over the pack entirely. Pruning the invalid entries is relatively unimportant because they shouldn't be very common, a $GIT_DIRECTORY/objects/pack directory tends to only have valid pack files. Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Shawn O. Pearce 098ac57a 2009-01-03T00:02:25 Refactor pack memory management and locking to be safer Using an atomic reference counter is difficult to make cross-platform, as the reference count implementations are generally processor specific. Its also hard to do a proper multi-read/single-write implementation. We now use a simple mutex around the reference count for the list of packs. Readers grab the mutex and either build the list, or increment the existing one's reference count. When the reader is done with the list, the reference count is decremented. In this way parallel readers are able to operate on the list without worrying about it being deallocated out from under them. Individual pack structures are held by reference counts, but we only care about the list the pack structure is held in. There is no need to increment/decrement the pack reference counts as we scan through them during a read operation, the caller holds the git_packlist and that is sufficient to hold the packs it references. Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Ramsay Jones 3a33c7b3 2009-01-02T20:51:47 Fix snprintf compiler warning on cygwin As far as gcc is concerned, the "z size specifier" is available as an extension to the language, which is available with or without any -std= switch. (I think you have to go back to 2.95 for a version of gcc which doesn't work.) Many other compilers have this as an extension as well (ie without the equivalent of -std=c99). Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Shawn O. Pearce b438016e 2008-12-31T16:20:05 Find pack files in $GIT_DIR/objects/pack directory on git_odb_open Currently we only catalog the available pack files into a table, storing their path names relative to the pack directory. Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Shawn O. Pearce 5614dc18 2008-12-31T13:27:51 Add basic locking to the git_odb structure We grab the lock while accessing the alternates list, ensuring that we only initialize it once for the given git_odb. Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Shawn O. Pearce d44cfd46 2008-12-31T13:16:31 Cleanup our header inclusion order to ensure pthread.h is early If we are using threads we need to make sure pthread.h comes in before just about anything else. Some platforms enable macros that alter what other headers define. Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Shawn O. Pearce 64a47c01 2008-12-30T23:21:36 Wrap malloc and friends and report out of memory as GIT_ENOMEM We now forbid direct use of malloc, strdup or calloc within the library and instead use wrapper functions git__malloc, etc. to invoke the underlying library malloc and set git_errno to a no memory error code if the allocation fails. In the future once we have pack objects in memory we are likely to enhance these routines with garbage collection logic to purge cached pack data when allocations fail. Because the size of the function will grow somewhat large, we don't want to mark them for inline as gcc tends to aggressively inline, creating larger than expected executables. Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Shawn O. Pearce ffb55c53 2008-12-30T22:29:04 Rename the path of the objects directory to be more specific We're likely to add additional path data, like the path of the refs or the path to the config file into the git_odb structure, as it may grow into the repository wrapper. Changing the name of the objects directory reference makes it more clear should we later add something else. Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Shawn O. Pearce 4c67e2e9 2008-12-30T22:25:30 Change git_odb__read_packed to return ENOTFOUND until implemented We didn't search for the object, so we cannot possibly promise it to the caller of git_odb_read(). Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Shawn O. Pearce 064301cc 2008-12-30T22:07:56 Fix size_t snprintf warning by using PRIuPTR format macro This is the correct C99 format code for the size_t type when passed as an argument to the *printf family. If the platform doesn't define it, we assume %lu and just cross our fingers that its the proper setting for a size_t on this system. On most sane platforms, "unsigned long" is the underlying type of "size_t". Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Ramsay Jones c960d6a3 2008-12-27T18:59:43 Add a routine to determine a git_oid given an git_obj Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Ramsay Jones 3d3552e8 2008-12-18T22:58:10 Implement git_odb__read_loose() Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Ramsay Jones 7b6e8067 2008-12-10T18:31:28 Add some git_otype string conversion and testing routines Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Andreas Ericsson dff79e27 2008-11-18T00:59:36 Rename "git_sobj" "git_obj" The 's' never really made sense, since it's not a "small" object at all, but rather a plain object. As such, it should have a "plain" object name. Signed-off-by: Andreas Ericsson <ae@op5.se> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Shawn O. Pearce 1699efc4 2008-11-03T18:39:37 Implement some of the basic git_odb open and close API Far from being complete, but its a good start. Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Shawn O. Pearce 50298f44 2008-11-01T15:55:01 Switch the license from BSD to GPL+libgcc exception Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Shawn O. Pearce d1ea30c3 2008-11-01T15:42:23 Move include files to include/git/, drop git_ prefix from file names Signed-off-by: Shawn O. Pearce <spearce@spearce.org>