kernel/git - git - PowerEL Git System

Commit Graph

Author	SHA1	Message	Date
René Scharfe	9ed0d8d6e6	use QSORT Apply the semantic patch contrib/coccinelle/qsort.cocci to the code base, replacing calls of qsort(3) with QSORT. The resulting code is shorter and supports empty arrays with NULL pointers. Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>	8 years ago
Jeff King	3157c880f6	sha1_file: drop free_pack_by_name The point of this function is to drop an entry from the "packed_git" cache that points to a file we might be overwriting, because our contents may not be the same (and hence the only caller was pack-objects as it moved a temporary packfile into place). In older versions of git, this could happen because the names of packfiles were derived from the set of objects they contained, not the actual bits on disk. But since `1190a1a` (pack-objects: name pack files after trailer hash, 2013-12-05), the name reflects the actual bits on disk, and any two packfiles with the same name can be used interchangeably. Dropping this function not only saves a few lines of code, it makes the lifetime of "struct packed_git" much easier to reason about: namely, we now do not ever free these structs. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>	9 years ago
René Scharfe	d773144417	pack-write: simplify index_pack_lockfile using skip_prefix() and xstrfmt() Get rid of magic string length constants by using skip_prefix() instead of memcmp() and use xstrfmt() for building a string instead of a PATH_MAX-sized buffer, snprintf() and xstrdup(). Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>	11 years ago
Sun He	5889271114	finish_tmp_packfile():use strbuf for pathname construction The old version fixes a maximum length on the buffer, which could be a problem if one is not certain of the length of get_object_directory(). Using strbuf can avoid the protential bug. Helped-by: Michael Haggerty <mhagger@alum.mit.edu> Helped-by: Eric Sunshine <sunshine@sunshineco.com> Signed-off-by: Sun He <sunheehnus@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>	11 years ago
Vicent Marti	7cc8f97108	pack-objects: implement bitmap writing This commit extends more the functionality of `pack-objects` by allowing it to write out a `.bitmap` index next to any written packs, together with the `.idx` index that currently gets written. If bitmap writing is enabled for a given repository (either by calling `pack-objects` with the `--write-bitmap-index` flag or by having `pack.writebitmaps` set to `true` in the config) and pack-objects is writing a packfile that would normally be indexed (i.e. not piping to stdout), we will attempt to write the corresponding bitmap index for the packfile. Bitmap index writing happens after the packfile and its index has been successfully written to disk (`finish_tmp_packfile`). The process is performed in several steps: 1. `bitmap_writer_set_checksum`: this call stores the partial checksum for the packfile being written; the checksum will be written in the resulting bitmap index to verify its integrity 2. `bitmap_writer_build_type_index`: this call uses the array of `struct object_entry` that has just been sorted when writing out the actual packfile index to disk to generate 4 type-index bitmaps (one for each object type). These bitmaps have their nth bit set if the given object is of the bitmap's type. E.g. the nth bit of the Commits bitmap will be 1 if the nth object in the packfile index is a commit. This is a very cheap operation because the bitmap writing code has access to the metadata stored in the `struct object_entry` array, and hence the real type for each object in the packfile. 3. `bitmap_writer_reuse_bitmaps`: if there exists an existing bitmap index for one of the packfiles we're trying to repack, this call will efficiently rebuild the existing bitmaps so they can be reused on the new index. All the existing bitmaps will be stored in a `reuse` hash table, and the commit selection phase will prioritize these when selecting, as they can be written directly to the new index without having to perform a revision walk to fill the bitmap. This can greatly speed up the repack of a repository that already has bitmaps. 4. `bitmap_writer_select_commits`: if bitmap writing is enabled for a given `pack-objects` run, the sequence of commits generated during the Counting Objects phase will be stored in an array. We then use that array to build up the list of selected commits. Writing a bitmap in the index for each object in the repository would be cost-prohibitive, so we use a simple heuristic to pick the commits that will be indexed with bitmaps. The current heuristics are a simplified version of JGit's original implementation. We select a higher density of commits depending on their age: the 100 most recent commits are always selected, after that we pick 1 commit of each 100, and the gap increases as the commits grow older. On top of that, we make sure that every single branch that has not been merged (all the tips that would be required from a clone) gets their own bitmap, and when selecting commits between a gap, we tend to prioritize the commit with the most parents. Do note that there is no right/wrong way to perform commit selection; different selection algorithms will result in different commits being selected, but there's no such thing as "missing a commit". The bitmap walker algorithm implemented in `prepare_bitmap_walk` is able to adapt to missing bitmaps by performing manual walks that complete the bitmap: the ideal selection algorithm, however, would select the commits that are more likely to be used as roots for a walk in the future (e.g. the tips of each branch, and so on) to ensure a bitmap for them is always available. 5. `bitmap_writer_build`: this is the computationally expensive part of bitmap generation. Based on the list of commits that were selected in the previous step, we perform several incremental walks to generate the bitmap for each commit. The walks begin from the oldest commit, and are built up incrementally for each branch. E.g. consider this dag where A, B, C, D, E, F are the selected commits, and a, b, c, e are a chunk of simplified history that will not receive bitmaps. A---a---B--b--C--c--D \ E--e--F We start by building the bitmap for A, using A as the root for a revision walk and marking all the objects that are reachable until the walk is over. Once this bitmap is stored, we reuse the bitmap walker to perform the walk for B, assuming that once we reach A again, the walk will be terminated because A has already been SEEN on the previous walk. This process is repeated for C, and D, but when we try to generate the bitmaps for E, we can reuse neither the current walk nor the bitmap we have generated so far. What we do now is resetting both the walk and clearing the bitmap, and performing the walk from scratch using E as the origin. This new walk, however, does not need to be completed. Once we hit B, we can lookup the bitmap we have already stored for that commit and OR it with the existing bitmap we've composed so far, allowing us to limit the walk early. After all the bitmaps have been generated, another iteration through the list of commits is performed to find the best XOR offsets for compression before writing them to disk. Because of the incremental nature of these bitmaps, XORing one of them with its predecesor results in a minimal "bitmap delta" most of the time. We can write this delta to the on-disk bitmap index, and then re-compose the original bitmaps by XORing them again when loaded. This is a phase very similar to pack-object's `find_delta` (using bitmaps instead of objects, of course), except the heuristics have been greatly simplified: we only check the 10 bitmaps before any given one to find best compressing one. This gives good results in practice, because there is locality in the ordering of the objects (and therefore bitmaps) in the packfile. 6. `bitmap_writer_finish`: the last step in the process is serializing to disk all the bitmap data that has been generated in the two previous steps. The bitmap is written to a tmp file and then moved atomically to its final destination, using the same process as `pack-write.c:write_idx_file`. Signed-off-by: Vicent Marti <tanoku@gmail.com> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>	11 years ago
Jeff King	9af270e8c2	do not pretend sha1write returns errors The sha1write function returns an int, but it will always be "0". The failure-prone parts of the function happen in the "flush" callback, which cannot pass an error back to us. So we just end up calling die() during the flush. Let's just drop the return value altogether, as it only confuses callers into thinking that it might be useful. Only one call site actually checked the return value. We can drop that check, since it just led to a die() anyway. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>	11 years ago
Jeff King	1190a1acf8	pack-objects: name pack files after trailer hash Our current scheme for naming packfiles is to calculate the sha1 hash of the sorted list of objects contained in the packfile. This gives us a unique name, so we are reasonably sure that two packs with the same name will contain the same objects. It does not, however, tell us that two such packs have the exact same bytes. This makes things awkward if we repack the same set of objects. Due to run-to-run variations, the bytes may not be identical (e.g., changed zlib or git versions, different source object reuse due to new packs in the repository, or even different deltas due to races during a multi-threaded delta search). In theory, this could be helpful to a program that cares that the packfile contains a certain set of objects, but does not care about the particular representation. In practice, no part of git makes use of that, and in many cases it is potentially harmful. For example, if a dumb http client fetches the .idx file, it must be sure to get the exact .pack that matches it. Similarly, a partial transfer of a .pack file cannot be safely resumed, as the actual bytes may have changed. This could also affect a local client which opened the .idx and .pack files, closes the .pack file (due to memory or file descriptor limits), and then re-opens a changed packfile. In all of these cases, git can detect the problem, as we have the sha1 of the bytes themselves in the pack trailer (which we verify on transfer), and the .idx file references the trailer from the matching packfile. But it would be simpler and more efficient to actually get the correct bytes, rather than noticing the problem and having to restart the operation. This patch simply uses the pack trailer sha1 as the pack name. It should be similarly unique, but covers the exact representation of the objects. Other parts of git should not care, as the pack name is returned by pack-objects and is essentially opaque. One test needs to be updated, because it actually corrupts a pack and expects that re-packing the corrupted bytes will use the same name. It won't anymore, but we can easily just use the name that pack-objects hands back. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>	11 years ago
Ævar Arnfjörð Bjarmason	ab1900a36e	Appease Sun Studio by renaming "tmpfile" On Solaris the system headers define the "tmpfile" name, which'll cause Git compiled with Sun Studio 12 Update 1 to whine about us redefining the name: "pack-write.c", line 76: warning: name redefined by pragma redefine_extname declared static: tmpfile (E_PRAGMA_REDEFINE_STATIC) "sha1_file.c", line 2455: warning: name redefined by pragma redefine_extname declared static: tmpfile (E_PRAGMA_REDEFINE_STATIC) "fast-import.c", line 858: warning: name redefined by pragma redefine_extname declared static: tmpfile (E_PRAGMA_REDEFINE_STATIC) "builtin/index-pack.c", line 175: warning: name redefined by pragma redefine_extname declared static: tmpfile (E_PRAGMA_REDEFINE_STATIC) Just renaming the "tmpfile" variable to "tmp_file" in the relevant places is the easiest way to fix this. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>	13 years ago
Junio C Hamano	68be2fea50	receive-pack, fetch-pack: reject bogus pack that records objects twice When receive-pack & fetch-pack are run and store the pack obtained over the wire to a local repository, they internally run the index-pack command with the --strict option. Make sure that we reject incoming packfile that records objects twice to avoid spreading such a damage. Signed-off-by: Junio C Hamano <gitster@pobox.com>	13 years ago
Junio C Hamano	0e990530ae	finish_tmp_packfile(): a helper function Factor out a small logic out of the private write_pack_file() function in builtin/pack-objects.c. This changes the order of finishing multi-pack generation slightly. The code used to - adjust shared perm of temporary packfile - rename temporary packfile to the final name - update mtime of the packfile under the final name - adjust shared perm of temporary idxfile - rename temporary idxfile to the final name but because the helper does not want to do the mtime thing, the updated code does that step first and then all the rest. Signed-off-by: Junio C Hamano <gitster@pobox.com>	13 years ago
Junio C Hamano	cdf9db3c83	create_tmp_packfile(): a helper function Factor out a small logic out of the private write_pack_file() function in builtin/pack-objects.c Signed-off-by: Junio C Hamano <gitster@pobox.com>	13 years ago
Junio C Hamano	c0ad465725	write_pack_header(): a helper function Factor out a small logic out of the private write_pack_file() function in builtin/pack-objects.c Signed-off-by: Junio C Hamano <gitster@pobox.com>	13 years ago
Junio C Hamano	3c9fc074c2	index-pack --verify: read anomalous offsets from v2 idx file A pack v2 .idx file usually records offset using 64-bit representation only when the offset does not fit within 31-bit, but you can handcraft your .idx file to record smaller offset using 64-bit, storing all zero in the upper 4-byte. By inspecting the original idx file when running index-pack --verify, encode such low offsets that do not need to be in 64-bit but are encoded using 64-bit just like the original idx file so that we can still validate the pack/idx pair by comparing the idx file recomputed with the original. Signed-off-by: Junio C Hamano <gitster@pobox.com>	14 years ago
Junio C Hamano	fb956c1f44	write_idx_file: need_large_offset() helper function Signed-off-by: Junio C Hamano <gitster@pobox.com>	14 years ago
Junio C Hamano	e337a04de2	index-pack: --verify Given an existing .pack file and the .idx file that describes it, this new mode of operation reads and re-index the packfile and makes sure the existing .idx file matches the result byte-for-byte. All the objects in the .pack file are validated during this operation as well. Unlike verify-pack, which visits each object described in the .idx file in the SHA-1 order, index-pack efficiently exploits the delta-chain to avoid rebuilding the objects that are used as the base of deltified objects over and over again while validating the objects, resulting in much quicker verification of the .pack file and its .idx file. This version however cannot verify a .pack/.idx pair with a handcrafted v2 index that uses 64-bit offset representation for offsets that would fit within 31-bit. You can create such an .idx file by giving a custom offset to --index-version option to the command. Signed-off-by: Junio C Hamano <gitster@pobox.com>	14 years ago
Junio C Hamano	ebcfb3791a	write_idx_file: introduce a struct to hold idx customization options Remove two globals, pack_idx_default version and pack_idx_off32_limit, and place them in a pack_idx_option structure. Allow callers to pass it to write_idx_file() as a parameter. Adjust all callers to the API change. Signed-off-by: Junio C Hamano <gitster@pobox.com>	14 years ago
Nicolas Pitre	f965c525a4	move encode_in_pack_object_header() to a better place Commit `1b22b6c897` made duplicated versions of encode_header() into a common version called encode_in_pack_object_header(). There is however a better location that sha1_file.c for such a function though, as sha1_file.c contains nothing related to the creation of packs, and it is quite populated already. Also the comment that was moved to the header file should really remain near the function as it covers implementation details and provides no information about the actual function interface. Signed-off-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>	15 years ago
Linus Torvalds	3bb7256281	make "index-pack" a built-in This required some fairly trivial packfile function 'const' cleanup, since the builtin commands get a const char *argv[] array. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>	15 years ago
Thomas Rast	d824cbba02	Convert existing die(..., strerror(errno)) to die_errno() Change calls to die(..., strerror(errno)) to use the new die_errno(). In the process, also make slight style adjustments: at least state _something_ about the function that failed (instead of just printing the pathname), and put paths in single quotes. Signed-off-by: Thomas Rast <trast@student.ethz.ch> Signed-off-by: Junio C Hamano <gitster@pobox.com>	16 years ago
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>	16 years ago
Nicolas Pitre	9126f0091f	fix openssl headers conflicting with custom SHA1 implementations On ARM I have the following compilation errors: CC fast-import.o In file included from cache.h:8, from builtin.h:6, from fast-import.c:142: arm/sha1.h:14: error: conflicting types for 'SHA_CTX' /usr/include/openssl/sha.h:105: error: previous declaration of 'SHA_CTX' was here arm/sha1.h:16: error: conflicting types for 'SHA1_Init' /usr/include/openssl/sha.h:115: error: previous declaration of 'SHA1_Init' was here arm/sha1.h:17: error: conflicting types for 'SHA1_Update' /usr/include/openssl/sha.h:116: error: previous declaration of 'SHA1_Update' was here arm/sha1.h:18: error: conflicting types for 'SHA1_Final' /usr/include/openssl/sha.h:117: error: previous declaration of 'SHA1_Final' was here make: *** [fast-import.o] Error 1 This is because openssl header files are always included in git-compat-util.h since commit `684ec6c63c` whenever NO_OPENSSL is not set, which somehow brings in <openssl/sha1.h> clashing with the custom ARM version. Compilation of git is probably broken on PPC too for the same reason. Turns out that the only file requiring openssl/ssl.h and openssl/err.h is imap-send.c. But only moving those problematic includes there doesn't solve the issue as it also includes cache.h which brings in the conflicting local SHA1 header file. As suggested by Jeff King, the best solution is to rename our references to SHA1 functions and structure to something git specific, and define those according to the implementation used. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>	17 years ago
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>	17 years ago
Nicolas Pitre	d35825da6d	fixup_pack_header_footer(): use nicely aligned buffer sizes It should be more efficient to use nicely aligned buffer sizes, either for filesystem operations or SHA1 checksums. Also, using a relatively small nominal size might allow for the data to remain in L1 cache between both SHA1_Update() calls. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>	17 years ago
Nicolas Pitre	abeb40e5aa	improve reliability of fixup_pack_header_footer() Currently, this function has the potential to read corrupted pack data from disk and give it a valid SHA1 checksum. Let's add the ability to validate SHA1 checksum of existing data along the way, including before and after any arbitrary point in the pack. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>	17 years ago
Linus Torvalds	0c68d386da	index-pack: be careful after fixing up the header/footer The index-pack command, when processing a thin pack, fixed up the pack after-the-fact. It forgets to fsync the result, because it only did that in one path rather in all cases of fixup. This moves the fsync_or_die() to the fix-up routine itself, rather than doing it in one of the callers, so that all cases are covered. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>	17 years ago
Nicolas Pitre	c0a5e2d477	pack.indexversion config option now defaults to 2 As announced for 1.6.0. Git older than version 1.5.2 (or any other git version with this option set to 1) may revert to version 1 of the pack index by manually deleting all .idx files and recreating them using 'git index-pack'. Communication over the git native protocol is unaffected since the pack index is never transferred. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>	17 years ago
Linus Torvalds	4c81b03e30	Make pack creation always fsync() the result This means that we can depend on packs always being stable on disk, simplifying a lot of the object serialization worries. And unlike loose objects, serializing pack creation IO isn't going to be a performance killer. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>	17 years ago
Heikki Orsila	c697ad143b	Cleanup xread() loops to use read_in_full() Signed-off-by: Heikki Orsila <heikki.orsila@iki.fi> Signed-off-by: Junio C Hamano <gitster@pobox.com>	17 years ago
Nicolas Pitre	4049b9cfc0	fix const issues with some functions Two functions, namely write_idx_file() and open_pack_file(), currently return a const pointer. However that pointer is either a copy of the first argument, or set to a malloc'd buffer when that first argument is null. In the later case it is wrong to qualify that pointer as const since ownership of the buffer is transferred to the caller to dispose of, and obviously the free() function is not meant to be passed const pointers. Making the return pointer not const causes a warning when the first argument is returned since that argument is also marked const. The correct thing to do is therefore to remove the const qualifiers, avoiding the need for ugly casts only to silence some warnings. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>	17 years ago
Shawn O. Pearce	106764e651	Refactor index-pack "keep $sha1" handling for reuse There is a subtle (but important) linkage between receive-pack and index-pack that allows index-pack to create a packfile but protect it from being deleted by a concurrent `git repack -a -d` operation. The linkage works by having index-pack mark the newly created pack with a ".keep" file and then it passes the SHA-1 name of that new packfile to receive-pack along its stdout channel. The receive-pack process must unkeep the packfile by deleting the .keep file, but can it can only do so after all elgible refs have been updated in the receiving repository. This ensures that the packfile is either kept or its objects are reachable, preventing a concurrent repacker from deleting the packfile before it can determine that its objects are actually needed by the repository. The new builtin-fetch code needs to perform the same actions if it choose to run index-pack rather than unpack-objects, so I am moving this code out to its own function where both receive-pack and fetch-pack are able to invoke it when necessary. The caller is responsible for deleting the returned ".keep" and freeing the path if the returned path is not NULL. Signed-off-by: Shawn O. Pearce <spearce@spearce.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>	18 years ago
Luiz Fernando N. Capitulino	7647b17f1d	Use xmkstemp() instead of mkstemp() xmkstemp() performs error checking and prints a standard error message when an error occur. Signed-off-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br> Signed-off-by: Junio C Hamano <gitster@pobox.com>	18 years ago
Geert Bosch	aa7e44bf57	Unify write_index_file functions This patch unifies the write_index_file functions in builtin-pack-objects.c and index-pack.c. As the name "index" is overloaded in git, move in the direction of using "idx" and "pack idx" when refering to the pack index. There should be no change in functionality. Signed-off-by: Geert Bosch <bosch@gnat.com> Acked-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <junkio@cox.net>	18 years ago
Johan Herland	2924415f4f	Fix signedness on return value from xread() The return value from xread() is ssize_t. Paolo Teti <paolo.teti@gmail.com> pointed out that in this case, the signed return value was assigned to an unsigned type (size_t). This patch fixes that. Signed-off-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <junkio@cox.net>	18 years ago
Dana L. How	8b0eca7c7b	Create pack-write.c for common pack writing code Include a generalized fixup_pack_header_footer() in this new file. Needed by git-repack --max-pack-size feature in a later patchset. [sp: Moved close(pack_fd) to callers, to support index-pack, and changed name to better indicate it is for packfiles.] Signed-off-by: Dana L. How <danahow@gmail.com> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>	18 years ago

39 Commits (1a5fccc0c26b4a8abafd85a73558022e65f6f8cf)