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2016-10-11Merge branch 'jc/verify-loose-object-header' into maintLibravatar Junio C Hamano1-2/+24
Codepaths that read from an on-disk loose object were too loose in validating what they are reading is a proper object file and sometimes read past the data they read from the disk, which has been corrected. H/t to Gustavo Grieco for reporting. * jc/verify-loose-object-header: unpack_sha1_header(): detect malformed object header streaming: make sure to notice corrupt object
2016-09-26unpack_sha1_header(): detect malformed object headerLibravatar Junio C Hamano1-2/+24
When opening a loose object file, we often do this sequence: - prepare a short buffer for the object header (on stack) - call unpack_sha1_header() and have early part of the object data inflated, enough to fill the buffer - parse that data in the short buffer, assuming that the first part of the object is <typename> SP <length> NUL Because the parsing function parse_sha1_header_extended() is not given the number of bytes inflated into the header buffer, it you craft a file whose early part inflates a garbage sequence without SP or NUL, and replace a loose object with it, it will end up reading past the end of the inflated data. To correct this, do the following four things: - rename unpack_sha1_header() to unpack_sha1_short_header() and have unpack_sha1_header_to_strbuf() keep calling that as its helper function. This will detect and report zlib errors, but is not aware of the format of a loose object (as before). - introduce unpack_sha1_header() that calls the same helper function, and when zlib reports it inflated OK into the buffer, check if the inflated data has NUL. This would ensure that parsing function will terminate within the buffer that holds the inflated header. - update unpack_sha1_header_to_strbuf() to check if the resulting buffer has NUL for the same effect. - update parse_sha1_header_extended() to make sure that its loop to find the SP that terminates the <typename> stops at NUL. Essentially, this makes unpack_*() functions that are asked to unpack a loose object header to be a bit more strict and detect an input that cannot possibly be a valid object header, even before the parsing function kicks in. Reported-by: Gustavo Grieco <gustavo.grieco@imag.fr> Helped-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-08-12Merge branch 'vs/typofix'Libravatar Junio C Hamano1-1/+1
* vs/typofix: Spelling fixes
2016-08-11Spelling fixesLibravatar Ville Skyttä1-1/+1
<BAD> <CORRECTED> accidently accidentally commited committed dependancy dependency emtpy empty existance existence explicitely explicitly git-upload-achive git-upload-archive hierachy hierarchy indegee indegree intial initial mulitple multiple non-existant non-existent precendence. precedence. priviledged privileged programatically programmatically psuedo-binary pseudo-binary soemwhere somewhere successfull successful transfering transferring uncommited uncommitted unkown unknown usefull useful writting writing Signed-off-by: Ville Skyttä <ville.skytta@iki.fi> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-08-10Merge branch 'js/am-3-merge-recursive-direct'Libravatar Junio C Hamano1-2/+2
"git am -3" calls "git merge-recursive" when it needs to fall back to a three-way merge; this call has been turned into an internal subroutine call instead of spawning a separate subprocess. * js/am-3-merge-recursive-direct: merge-recursive: flush output buffer even when erroring out merge_trees(): ensure that the callers release output buffer merge-recursive: offer an option to retain the output in 'obuf' merge-recursive: write the commit title in one go merge-recursive: flush output buffer before printing error messages am -3: use merge_recursive() directly again merge-recursive: switch to returning errors instead of dying merge-recursive: handle return values indicating errors merge-recursive: allow write_tree_from_memory() to error out merge-recursive: avoid returning a wholesale struct merge_recursive: abort properly upon errors prepare the builtins for a libified merge_recursive() merge-recursive: clarify code in was_tracked() die(_("BUG")): avoid translating bug messages die("bug"): report bugs consistently t5520: verify that `pull --rebase` shows the helpful advice when failing
2016-08-08Merge branch 'jk/pack-objects-optim'Libravatar Junio C Hamano1-48/+18
"git pack-objects" has a few options that tell it not to pack objects found in certain packfiles, which require it to scan .idx files of all available packs. The codepaths involved in these operations have been optimized for a common case of not having any non-local pack and/or any .kept pack. * jk/pack-objects-optim: pack-objects: compute local/ignore_pack_keep early pack-objects: break out of want_object loop early find_pack_entry: replace last_found_pack with MRU cache add generic most-recently-used list sha1_file: drop free_pack_by_name t/perf: add tests for many-pack scenarios
2016-07-29find_pack_entry: replace last_found_pack with MRU cacheLibravatar Jeff King1-18/+18
Each pack has an index for looking up entries in O(log n) time, but if we have multiple packs, we have to scan through them linearly. This can produce a measurable overhead for some operations. We dealt with this long ago in f7c22cc (always start looking up objects in the last used pack first, 2007-05-30), which keeps what is essentially a 1-element most-recently-used cache. In theory, we should be able to do better by keeping a similar but longer cache, that is the same length as the pack-list itself. Since we now have a convenient generic MRU structure, we can plug it in and measure. Here are the numbers for running p5303 against linux.git: Test HEAD^ HEAD ------------------------------------------------------------------------ 5303.3: rev-list (1) 31.56(31.28+0.27) 31.30(31.08+0.20) -0.8% 5303.4: repack (1) 40.62(39.35+2.36) 40.60(39.27+2.44) -0.0% 5303.6: rev-list (50) 31.31(31.06+0.23) 31.23(31.00+0.22) -0.3% 5303.7: repack (50) 58.65(69.12+1.94) 58.27(68.64+2.05) -0.6% 5303.9: rev-list (1000) 38.74(38.40+0.33) 31.87(31.62+0.24) -17.7% 5303.10: repack (1000) 367.20(441.80+4.62) 342.00(414.04+3.72) -6.9% The main numbers of interest here are the rev-list ones (since that is exercising the normal object lookup code path). The single-pack case shouldn't improve at all; the 260ms speedup there is just part of the run-to-run noise (but it's important to note that we didn't make anything worse with the overhead of maintaining our cache). In the 50-pack case, we see similar results. There may be a slight improvement, but it's mostly within the noise. The 1000-pack case does show a big improvement, though. That carries over to the repack case, as well. Even though we haven't touched its pack-search loop yet, it does still do a lot of normal object lookups (e.g., for the internal revision walk), and so improves. As a point of reference, I also ran the 1000-pack test against a version of HEAD^ with the last_found_pack optimization disabled. It takes ~60s, so that gives an indication of how much even the single-element cache is helping. For comparison, here's a smaller repository, git.git: Test HEAD^ HEAD --------------------------------------------------------------------- 5303.3: rev-list (1) 1.56(1.54+0.01) 1.54(1.51+0.02) -1.3% 5303.4: repack (1) 1.84(1.80+0.10) 1.82(1.80+0.09) -1.1% 5303.6: rev-list (50) 1.58(1.55+0.02) 1.59(1.57+0.01) +0.6% 5303.7: repack (50) 2.50(3.18+0.04) 2.50(3.14+0.04) +0.0% 5303.9: rev-list (1000) 2.76(2.71+0.04) 2.24(2.21+0.02) -18.8% 5303.10: repack (1000) 13.21(19.56+0.25) 11.66(18.01+0.21) -11.7% You can see that the percentage improvement is similar. That's because the lookup we are optimizing is roughly O(nr_objects * nr_packs). Since the number of packs is constant in both tests, we'd expect the improvement to be linear in the number of objects. But the whole process is also linear in the number of objects, so the improvement is a constant factor. The exact improvement does also depend on the contents of the packs. In p5303, the extra packs all have 5 first-parent commits in them, which is a reasonable simulation of a pushed-to repository. But it also means that only 250 first-parent commits are in those packs (compared to almost 50,000 total in linux.git), and the rest are in the huge "base" pack. So once we start looking at history in taht big pack, that's where we'll find most everything, and even the 1-element cache gets close to 100% cache hits. You could almost certainly show better numbers with a more pathological case (e.g., distributing the objects more evenly across the packs). But that's simply not that realistic a scenario, so it makes more sense to focus on these numbers. The implementation itself is a straightforward application of the MRU code. We provide an MRU-ordered list of packs that shadows the packed_git list. This is easy to do because we only create and revise the pack list in one place. The "reprepare" code path actually drops the whole MRU and replaces it for simplicity. It would be more efficient to just add new entries, but there's not much point in optimizing here; repreparing happens rarely, and only after doing a lot of other expensive work. The key things to keep optimized are traversal (which is just a normal linked list, albeit with one extra level of indirection over the regular packed_git list), and marking (which is a constant number of pointer assignments, though slightly more than the old last_found_pack was; it doesn't seem to create a measurable slowdown, though). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-07-29sha1_file: drop free_pack_by_nameLibravatar Jeff King1-30/+0
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>
2016-07-28Merge branch 'nd/pack-ofs-4gb-limit'Libravatar Junio C Hamano1-1/+1
"git pack-objects" and "git index-pack" mostly operate with off_t when talking about the offset of objects in a packfile, but there were a handful of places that used "unsigned long" to hold that value, leading to an unintended truncation. * nd/pack-ofs-4gb-limit: fsck: use streaming interface for large blobs in pack pack-objects: do not truncate result in-pack object size on 32-bit systems index-pack: correct "offset" type in unpack_entry_data() index-pack: report correct bad object offsets even if they are large index-pack: correct "len" type in unpack_data() sha1_file.c: use type off_t* for object_info->disk_sizep pack-objects: pass length to check_pack_crc() without truncation
2016-07-26die("bug"): report bugs consistentlyLibravatar Johannes Schindelin1-2/+2
The vast majority of error messages in Git's source code which report a bug use the convention to prefix the message with "BUG:". As part of cleaning up merge-recursive to stop die()ing except in case of detected bugs, let's just make the remainder of the bug reports consistent with the de facto rule. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-07-12pack-objects: pass length to check_pack_crc() without truncationLibravatar Nguyễn Thái Ngọc Duy1-1/+1
On 32 bit systems with large file support, unsigned long is 32-bit while the two offsets in the subtraction expression (pack-objects has the exact same expression as in sha1_file.c but not shown in diff) are in 64-bit. If an in-pack object is larger than 2^32 len/datalen is truncated and we get a misleading "error: bad packed object CRC for ..." as a result. Use off_t for len and datalen. check_pack_crc() already accepts this argument as off_t and can deal with 4+ GB. Noticed-by: Christoph Michelbach <michelbach94@gmail.com> Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-05-23Merge branch 'nd/worktree-various-heads'Libravatar Junio C Hamano1-1/+1
The experimental "multiple worktree" feature gains more safety to forbid operations on a branch that is checked out or being actively worked on elsewhere, by noticing that e.g. it is being rebased. * nd/worktree-various-heads: branch: do not rename a branch under bisect or rebase worktree.c: check whether branch is bisected in another worktree wt-status.c: split bisect detection out of wt_status_get_state() worktree.c: check whether branch is rebased in another worktree worktree.c: avoid referencing to worktrees[i] multiple times wt-status.c: make wt_status_check_rebase() work on any worktree wt-status.c: split rebase detection out of wt_status_get_state() path.c: refactor and add worktree_git_path() worktree.c: mark current worktree worktree.c: make find_shared_symref() return struct worktree * worktree.c: store "id" instead of "git_dir" path.c: add git_common_path() and strbuf_git_common_path() dir.c: rename str(n)cmp_icase to fspath(n)cmp
2016-05-09sha1_file.c: use {error,die,warning}_errno()Libravatar Nguyễn Thái Ngọc Duy1-19/+13
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-04-22dir.c: rename str(n)cmp_icase to fspath(n)cmpLibravatar Nguyễn Thái Ngọc Duy1-1/+1
These functions compare two paths that are taken from file system. Depending on the running file system, paths may need to be compared case-sensitively or not, and maybe even something else in future. The current names do not convey that well. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-03-04Merge branch 'jk/pack-idx-corruption-safety'Libravatar Junio C Hamano1-0/+17
The code to read the pack data using the offsets stored in the pack idx file has been made more carefully check the validity of the data in the idx. * jk/pack-idx-corruption-safety: sha1_file.c: mark strings for translation use_pack: handle signed off_t overflow nth_packed_object_offset: bounds-check extended offset t5313: test bounds-checks of corrupted/malicious pack/idx files
2016-02-27sha1_file.c: mark strings for translationLibravatar Nguyễn Thái Ngọc Duy1-3/+3
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-26Merge branch 'jk/tighten-alloc'Libravatar Junio C Hamano1-11/+13
Update various codepaths to avoid manually-counted malloc(). * jk/tighten-alloc: (22 commits) ewah: convert to REALLOC_ARRAY, etc convert ewah/bitmap code to use xmalloc diff_populate_gitlink: use a strbuf transport_anonymize_url: use xstrfmt git-compat-util: drop mempcpy compat code sequencer: simplify memory allocation of get_message test-path-utils: fix normalize_path_copy output buffer size fetch-pack: simplify add_sought_entry fast-import: simplify allocation in start_packfile write_untracked_extension: use FLEX_ALLOC helper prepare_{git,shell}_cmd: use argv_array use st_add and st_mult for allocation size computation convert trivial cases to FLEX_ARRAY macros use xmallocz to avoid size arithmetic convert trivial cases to ALLOC_ARRAY convert manual allocations to argv_array argv-array: add detach function add helpers for allocating flex-array structs harden REALLOC_ARRAY and xcalloc against size_t overflow tree-diff: catch integer overflow in combine_diff_path allocation ...
2016-02-25use_pack: handle signed off_t overflowLibravatar Jeff King1-0/+2
A v2 pack index file can specify an offset within a packfile of up to 2^64-1 bytes. On a system with a signed 64-bit off_t, we can represent only up to 2^63-1. This means that a corrupted .idx file can end up with a negative offset in the pack code. Our bounds-checking use_pack function looks for too-large offsets, but not for ones that have wrapped around to negative. Let's do so, which fixes an out-of-bounds access demonstrated in t5313. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-25nth_packed_object_offset: bounds-check extended offsetLibravatar Jeff King1-0/+15
If a pack .idx file has a corrupted offset for an object, we may try to access an offset in the .idx or .pack file that is larger than the file's size. For the .pack case, we have use_pack() to protect us, which realizes the access is out of bounds. But if the corrupted value asks us to look in the .idx file's secondary 64-bit offset table, we blindly add it to the mmap'd index data and access arbitrary memory. We can fix this with a simple bounds-check compared to the size we found when we opened the .idx file. Note that there's similar code in index-pack that is triggered only during "index-pack --verify". To support both, we pull the bounds-check into a separate function, which dies when it sees a corrupted file. It would be nice if we could return an error, so that the pack code could try to find a good copy of the object elsewhere. Currently nth_packed_object_offset doesn't have any way to return an error, but it could probably use "0" as a sentinel value (since no object can start there). This is the minimal fix, and we can improve the resilience later on top. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22use st_add and st_mult for allocation size computationLibravatar Jeff King1-9/+11
If our size computation overflows size_t, we may allocate a much smaller buffer than we expected and overflow it. It's probably impossible to trigger an overflow in most of these sites in practice, but it is easy enough convert their additions and multiplications into overflow-checking variants. This may be fixing real bugs, and it makes auditing the code easier. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22convert trivial cases to ALLOC_ARRAYLibravatar Jeff King1-2/+2
Each of these cases can be converted to use ALLOC_ARRAY or REALLOC_ARRAY, which has two advantages: 1. It automatically checks the array-size multiplication for overflow. 2. It always uses sizeof(*array) for the element-size, so that it can never go out of sync with the declared type of the array. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-01-15clone/sha1_file: read info/alternates with strbuf_getline()Libravatar Junio C Hamano1-1/+1
$GIT_OBJECT_DIRECTORY/info/alternates is a text file that can be edited with a DOS editor. We do not want to use the real path with CR appended at the end. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-01-15strbuf: introduce strbuf_getline_{lf,nul}()Libravatar Junio C Hamano1-1/+1
The strbuf_getline() interface allows a byte other than LF or NUL as the line terminator, but this is only because I wrote these codepaths anticipating that there might be a value other than NUL and LF that could be useful when I introduced line_termination long time ago. No useful caller that uses other value has emerged. By now, it is clear that the interface is overly broad without a good reason. Many codepaths have hardcoded preference to read either LF terminated or NUL terminated records from their input, and then call strbuf_getline() with LF or NUL as the third parameter. This step introduces two thin wrappers around strbuf_getline(), namely, strbuf_getline_lf() and strbuf_getline_nul(), and mechanically rewrites these call sites to call either one of them. The changes contained in this patch are: * introduction of these two functions in strbuf.[ch] * mechanical conversion of all callers to strbuf_getline() with either '\n' or '\0' as the third parameter to instead call the respective thin wrapper. After this step, output from "git grep 'strbuf_getline('" would become a lot smaller. An interim goal of this series is to make this an empty set, so that we can have strbuf_getline_crlf() take over the shorter name strbuf_getline(). Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-12-21Merge branch 'bc/format-patch-null-from-line'Libravatar Junio C Hamano1-0/+1
"format-patch" has learned a new option to zero-out the commit object name on the mbox "From " line. * bc/format-patch-null-from-line: format-patch: check that header line has expected format format-patch: add an option to suppress commit hash sha1_file.c: introduce a null_oid constant
2015-12-15Merge branch 'jk/prune-mtime'Libravatar Junio C Hamano1-2/+2
The helper used to iterate over loose object directories to prune stale objects did not closedir() immediately when it is done with a directory--a callback such as the one used for "git prune" may want to do rmdir(), but it would fail on open directory on platforms such as WinXP. * jk/prune-mtime: prune: close directory earlier during loose-object directory traversal
2015-12-14sha1_file.c: introduce a null_oid constantLibravatar brian m. carlson1-0/+1
null_oid is the struct object_id equivalent to null_sha1. Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-11-20sha1_file: introduce has_object_file helper.Libravatar brian m. carlson1-0/+5
Add has_object_file, which is a wrapper around has_sha1_file, but for struct object_id. Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Jeff King <peff@peff.net>
2015-11-20Merge branch 'dk/gc-idx-wo-pack'Libravatar Jeff King1-17/+6
Having a leftover .idx file without corresponding .pack file in the repository hurts performance; "git gc" learned to prune them. * dk/gc-idx-wo-pack: gc: remove garbage .idx files from pack dir t5304: test cleaning pack garbage prepare_packed_git(): refactor garbage reporting in pack directory
2015-10-30Merge branch 'js/misc-fixes'Libravatar Junio C Hamano1-1/+1
Various compilation fixes and squelching of warnings. * js/misc-fixes: Correct fscanf formatting string for I64u values Silence GCC's "cast of pointer to integer of a different size" warning Squelch warning about an integer overflow
2015-10-26Silence GCC's "cast of pointer to integer of a different size" warningLibravatar Johannes Schindelin1-1/+1
When calculating hashes from pointers, it actually makes sense to cut off the most significant bits. In that case, said warning does not make a whole lot of sense. So let's just work around it by casting the pointer first to intptr_t and then casting up/down to the final integral type. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-20Merge branch 'jk/war-on-sprintf'Libravatar Junio C Hamano1-67/+59
Many allocations that is manually counted (correctly) that are followed by strcpy/sprintf have been replaced with a less error prone constructs such as xstrfmt. Macintosh-specific breakage was noticed and corrected in this reroll. * jk/war-on-sprintf: (70 commits) name-rev: use strip_suffix to avoid magic numbers use strbuf_complete to conditionally append slash fsck: use for_each_loose_file_in_objdir Makefile: drop D_INO_IN_DIRENT build knob fsck: drop inode-sorting code convert strncpy to memcpy notes: document length of fanout path with a constant color: add color_set helper for copying raw colors prefer memcpy to strcpy help: clean up kfmclient munging receive-pack: simplify keep_arg computation avoid sprintf and strcpy with flex arrays use alloc_ref rather than hand-allocating "struct ref" color: add overflow checks for parsing colors drop strcpy in favor of raw sha1_to_hex use sha1_to_hex_r() instead of strcpy daemon: use cld->env_array when re-spawning stat_tracking_info: convert to argv_array http-push: use an argv_array for setup_revisions fetch-pack: use argv_array for index-pack / unpack-objects ...
2015-10-15Merge branch 'js/clone-dissociate'Libravatar Junio C Hamano1-22/+37
"git clone --dissociate" runs a big "git repack" process at the end, and it helps to close file descriptors that are open on the packs and their idx files before doing so on filesystems that cannot remove a file that is still open. * js/clone-dissociate: clone --dissociate: avoid locking pack files sha1_file.c: add a function to release all packs sha1_file: consolidate code to close a pack's file descriptor t5700: demonstrate a Windows file locking issue with `git clone --dissociate`
2015-10-07sha1_file.c: add a function to release all packsLibravatar Johannes Schindelin1-3/+20
On Windows, files that are in use cannot be removed or renamed. That means that we have to release pack files when we are about to, say, repack them. Let's introduce a convenient function to close all the pack files and their idx files. While at it, we consolidate the close windows/close fd/close index stanza in `free_pack_by_name()` into the `close_pack()` function that is used by the new `close_all_packs()` function to avoid repeated code. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-05sha1_file: consolidate code to close a pack's file descriptorLibravatar Johannes Schindelin1-20/+18
There was a lot of repeated code to close the file descriptor of a given pack. Let's just refactor this code into a single function. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-05avoid sprintf and strcpy with flex arraysLibravatar Jeff King1-2/+3
When we are allocating a struct with a FLEX_ARRAY member, we generally compute the size of the array and then sprintf or strcpy into it. Normally we could improve a dynamic allocation like this by using xstrfmt, but it doesn't work here; we have to account for the size of the rest of the struct. But we can improve things a bit by storing the length that we use for the allocation, and then feeding it to xsnprintf or memcpy, which makes it more obvious that we are not writing more than the allocated number of bytes. It would be nice if we had some kind of helper for allocating generic flex arrays, but it doesn't work that well: - the call signature is a little bit unwieldy: d = flex_struct(sizeof(*d), offsetof(d, path), fmt, ...); You need offsetof here instead of just writing to the end of the base size, because we don't know how the struct is packed (partially this is because FLEX_ARRAY might not be zero, though we can account for that; but the size of the struct may actually be rounded up for alignment, and we can't know that). - some sites do clever things, like over-allocating because they know they will write larger things into the buffer later (e.g., struct packed_git here). So we're better off to just write out each allocation (or add type-specific helpers, though many of these are one-off allocations anyway). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-05write_loose_object: convert to strbufLibravatar Jeff King1-20/+22
When creating a loose object tempfile, we use a fixed PATH_MAX-sized buffer, and strcpy directly into it. This isn't buggy, because we do a rough check of the size, but there's no verification that our guesstimate of the required space is enough (in fact, it's several bytes too big for the current naming scheme). Let's switch to a strbuf, which makes this much easier to verify. The allocation overhead should be negligible, since we are replacing a static buffer with a static strbuf, and we'll only need to allocate on the first call. While we're here, we can also document a subtle interaction with mkstemp that would be easy to overlook. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-25sha1_get_pack_name: use a strbufLibravatar Jeff King1-29/+10
We do some manual memory computation here, and there's no check that our 60 is not overflowed by the raw sprintf (it isn't, because the "which" parameter is never longer than "pack"). We can simplify this greatly with a strbuf. Technically the end result is not identical, as the original took care not to rewrite the object directory on each call for performance reasons. We could do that here, too (by saving the baselen and resetting to it), but it's not worth the complexity; this function is not called a lot (generally once per packfile that we open). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-25use strip_suffix and xstrfmt to replace suffixLibravatar Jeff King1-2/+4
When we want to convert "foo.pack" to "foo.idx", we do it by duplicating the original string and then munging the bytes in place. Let's use strip_suffix and xstrfmt instead, which has several advantages: 1. It's more clear what the intent is. 2. It does not implicitly rely on the fact that strlen(".idx") <= strlen(".pack") to avoid an overflow. 3. We communicate the assumption that the input file ends with ".pack" (and get a run-time check that this is so). 4. We drop calls to strcpy, which makes auditing the code base easier. Likewise, we can do this to convert ".pack" to ".bitmap", avoiding some manual memory computation. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-25add_packed_git: convert strcpy into xsnprintfLibravatar Jeff King1-8/+13
We have the path "foo.idx", and we create a buffer big enough to hold "foo.pack" and "foo.keep", and then strcpy straight into it. This isn't a bug (we have enough space), but it's very hard to tell from the strcpy that this is so. Let's instead use strip_suffix to take off the ".idx", record the size of our allocation, and use xsnprintf to make sure we don't violate our assumptions. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-25use xsnprintf for generating git object headersLibravatar Jeff King1-6/+7
We generally use 32-byte buffers to format git's "type size" header fields. These should not generally overflow unless you can produce some truly gigantic objects (and our types come from our internal array of constant strings). But it is a good idea to use xsnprintf to make sure this is the case. Note that we slightly modify the interface to write_sha1_file_prepare, which nows uses "hdrlen" as an "in" parameter as well as an "out" (on the way in it stores the allocated size of the header, and on the way out it returns the ultimate size of the header). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-09Sync with 2.5.2Libravatar Junio C Hamano1-6/+3
2015-09-04Sync with 2.4.9Libravatar Junio C Hamano1-6/+3
2015-09-04Sync with 2.3.9Libravatar Junio C Hamano1-6/+3
2015-09-04Sync with 2.2.3Libravatar Junio C Hamano1-6/+3
2015-09-04read_info_alternates: handle paths larger than PATH_MAXLibravatar Jeff King1-6/+3
This function assumes that the relative_base path passed into it is no larger than PATH_MAX, and writes into a fixed-size buffer. However, this path may not have actually come from the filesystem; for example, add_submodule_odb generates a path using a strbuf and passes it in. This is hard to trigger in practice, though, because the long submodule directory would have to exist on disk before we would try to open its info/alternates file. We can easily avoid the bug, though, by simply creating the filename on the heap. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-09-03Merge branch 'cb/open-noatime-clear-errno' into maintLibravatar Junio C Hamano1-1/+4
When trying to see that an object does not exist, a state errno leaked from our "first try to open a packfile with O_NOATIME and then if it fails retry without it" logic on a system that refuses O_NOATIME. This confused us and caused us to die, saying that the packfile is unreadable, when we should have just reported that the object does not exist in that packfile to the caller. * cb/open-noatime-clear-errno: git_open_noatime: return with errno=0 on success
2015-08-25Merge branch 'cb/open-noatime-clear-errno'Libravatar Junio C Hamano1-1/+4
When trying to see that an object does not exist, a state errno leaked from our "first try to open a packfile with O_NOATIME and then if it fails retry without it" logic on a system that refuses O_NOATIME. This confused us and caused us to die, saying that the packfile is unreadable, when we should have just reported that the object does not exist in that packfile to the caller. * cb/open-noatime-clear-errno: git_open_noatime: return with errno=0 on success
2015-08-19Merge branch 'jk/git-path'Libravatar Junio C Hamano1-7/+40
git_path() and mkpath() are handy helper functions but it is easy to misuse, as the callers need to be careful to keep the number of active results below 4. Their uses have been reduced. * jk/git-path: memoize common git-path "constant" files get_repo_path: refactor path-allocation find_hook: keep our own static buffer refs.c: remove_empty_directories can take a strbuf refs.c: avoid git_path assignment in lock_ref_sha1_basic refs.c: avoid repeated git_path calls in rename_tmp_log refs.c: simplify strbufs in reflog setup and writing path.c: drop git_path_submodule refs.c: remove extra git_path calls from read_loose_refs remote.c: drop extraneous local variable from migrate_file prefer mkpathdup to mkpath in assignments prefer git_pathdup to git_path in some possibly-dangerous cases add_to_alternates_file: don't add duplicate entries t5700: modernize style cache.h: complete set of git_path_submodule helpers cache.h: clarify documentation for git_path, et al
2015-08-19Merge branch 'jc/finalize-temp-file'Libravatar Junio C Hamano1-5/+2
Long overdue micro clean-up. * jc/finalize-temp-file: sha1_file.c: rename move_temp_to_file() to finalize_object_file()
2015-08-17prepare_packed_git(): refactor garbage reporting in pack directoryLibravatar Junio C Hamano1-17/+6
The hook to report "garbage" files in $GIT_OBJECT_DIRECTORY/pack/ could be generic but is too specific to count-object's needs. Move the part to produce human-readable messages to count-objects, and refine the interface to callback with the "bits" with values defined in the cache.h header file, so that other callers (e.g. prune) can later use the same mechanism to enumerate different kinds of garbage files and do something intelligent about them, other than reporting in textual messages. Signed-off-by: Junio C Hamano <gitster@pobox.com>