summaryrefslogtreecommitdiff
path: root/git-compat-util.h
AgeCommit message (Collapse)AuthorFilesLines
2017-01-23add QSORT_SLibravatar René Scharfe1-0/+5
Add the macro QSORT_S, a convenient wrapper for qsort_s() that infers the size of the array elements and dies on error. Basically all possible errors are programming mistakes (passing NULL as base of a non-empty array, passing NULL as comparison function, out-of-bounds accesses), so terminating the program should be acceptable for most callers. Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-23compat: add qsort_s()Libravatar René Scharfe1-0/+6
The function qsort_s() was introduced with C11 Annex K; it provides the ability to pass a context pointer to the comparison function, supports the convention of using a NULL pointer for an empty array and performs a few safety checks. Add an implementation based on compat/qsort.c for platforms that lack a native standards-compliant qsort_s() (i.e. basically everyone). It doesn't perform the full range of possible checks: It uses size_t instead of rsize_t and doesn't check nmemb and size against RSIZE_MAX because we probably don't have the restricted size type defined. For the same reason it returns int instead of errno_t. Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-31Merge branch 'jk/common-main'Libravatar Junio C Hamano1-2/+2
A trivial clean-up to a recently graduated topic. * jk/common-main: git-compat-util: move content inside ifdef/endif guards
2016-10-27git-compat-util: move content inside ifdef/endif guardsLibravatar Jeff King1-2/+2
Commit 3f2e2297b9 (add an extra level of indirection to main(), 2016-07-01) added a declaration to git-compat-util.h, but it was accidentally placed after the final #endif that guards against multiple inclusions. This doesn't have any actual impact on the code, since it's not incorrect to repeat a function declaration in C. But it's a bad habit, and makes it more likely for somebody else to make the same mistake. It also defeats gcc's optimization to avoid opening header files whose contents are completely guarded. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-26Merge branch 'jk/tighten-alloc'Libravatar Junio C Hamano1-11/+6
Protect our code from over-eager compilers. * jk/tighten-alloc: inline xalloc_flex() into FLEXPTR_ALLOC_MEM avoid pointer arithmetic involving NULL in FLEX_ALLOC_MEM
2016-10-17inline xalloc_flex() into FLEXPTR_ALLOC_MEMLibravatar René Scharfe1-9/+3
Allocate and copy directly in FLEXPTR_ALLOC_MEM and remove the now unused helper function xalloc_flex(). The resulting code is shorter and the offset arithmetic is a bit simpler. Suggested-by: Jeff King <peff@peff.net> Signed-off-by: Rene Scharfe <l.s.r@web.de> Reviewed-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-17avoid pointer arithmetic involving NULL in FLEX_ALLOC_MEMLibravatar René Scharfe1-2/+3
Calculating offsets involving a NULL pointer is undefined. It works in practice (for now?), but we should not rely on it. Allocate first and then simply refer to the flexible array member by its name instead of performing pointer arithmetic up front. The resulting code is slightly shorter, easier to read and doesn't rely on undefined behaviour. NB: The cast to a (non-const) void pointer is necessary to keep support for flexible array members declared as const. Signed-off-by: Rene Scharfe <l.s.r@web.de> Reviewed-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-10Merge branch 'rs/qsort'Libravatar Junio C Hamano1-0/+8
We call "qsort(array, nelem, sizeof(array[0]), fn)", and most of the time third parameter is redundant. A new QSORT() macro lets us omit it. * rs/qsort: show-branch: use QSORT use QSORT, part 2 coccicheck: use --all-includes by default remove unnecessary check before QSORT use QSORT add QSORT
2016-10-03Merge branch 'rs/copy-array'Libravatar Junio C Hamano1-0/+8
Code cleanup. * rs/copy-array: use COPY_ARRAY add COPY_ARRAY
2016-09-29add QSORTLibravatar René Scharfe1-0/+8
Add the macro QSORT, a convenient wrapper for qsort(3) that infers the size of the array elements and supports the convention of initializing empty arrays with a NULL pointer, which we use in some places. Calling qsort(3) directly with a NULL pointer is undefined -- even with an element count of zero -- and allows the compiler to optimize away any following NULL checks. Using the macro avoids such surprises. Add a semantic patch as well to demonstrate the macro's usage and to automate the transformation of trivial cases. Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-26Merge branch 'js/regexec-buf'Libravatar Junio C Hamano1-0/+13
Some codepaths in "git diff" used regexec(3) on a buffer that was mmap(2)ed, which may not have a terminating NUL, leading to a read beyond the end of the mapped region. This was fixed by introducing a regexec_buf() helper that takes a <ptr,len> pair with REG_STARTEND extension. * js/regexec-buf: regex: use regexec_buf() regex: add regexec_buf() that can work on a non NUL-terminated string regex: -G<pattern> feeds a non NUL-terminated string to regexec() and fails
2016-09-25add COPY_ARRAYLibravatar René Scharfe1-0/+8
Add COPY_ARRAY, a safe and convenient helper for copying arrays, complementing ALLOC_ARRAY and REALLOC_ARRAY. Users just specify source, destination and the number of elements; the size of an element is inferred automatically. It checks if the multiplication of size and element count overflows. The inferred size is passed first to st_mult, which allows the division there to be done at compilation time. As a basic type safety check it makes sure the sizes of source and destination elements are the same. That's evaluated at compilation time as well. COPY_ARRAY is safe to use with NULL as source pointer iff 0 elements are to be copied. That convention is used in some cases for initializing arrays. Raw memcpy(3) does not support it -- compilers are allowed to assume that only valid pointers are passed to it and can optimize away NULL checks after such a call. Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-21regex: add regexec_buf() that can work on a non NUL-terminated stringLibravatar Johannes Schindelin1-0/+13
We just introduced a test that demonstrates that our sloppy use of regexec() on a mmap()ed area can result in incorrect results or even hard crashes. So what we need to fix this is a function that calls regexec() on a length-delimited, rather than a NUL-terminated, string. Happily, there is an extension to regexec() introduced by the NetBSD project and present in all major regex implementation including Linux', MacOSX' and the one Git includes in compat/regex/: by using the (non-POSIX) REG_STARTEND flag, it is possible to tell the regexec() function that it should only look at the offsets between pmatch[0].rm_so and pmatch[0].rm_eo. That is exactly what we need. Since support for REG_STARTEND is so widespread by now, let's just introduce a helper function that always uses it, and tell people on a platform whose regex library does not support it to use the one from our compat/regex/ directory. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-19Merge branch 'cc/apply-am'Libravatar Junio C Hamano1-0/+3
"git am" has been taught to make an internal call to "git apply"'s innards without spawning the latter as a separate process. * cc/apply-am: (41 commits) builtin/am: use apply API in run_apply() apply: learn to use a different index file apply: pass apply state to build_fake_ancestor() apply: refactor `git apply` option parsing apply: change error_routine when silent usage: add get_error_routine() and get_warn_routine() usage: add set_warn_routine() apply: don't print on stdout in verbosity_silent mode apply: make it possible to silently apply apply: use error_errno() where possible apply: make some parsing functions static again apply: move libified code from builtin/apply.c to apply.{c,h} apply: rename and move opt constants to apply.h builtin/apply: rename option parsing functions builtin/apply: make create_one_file() return -1 on error builtin/apply: make try_create_file() return -1 on error builtin/apply: make write_out_results() return -1 on error builtin/apply: make write_out_one_result() return -1 on error builtin/apply: make create_file() return -1 on error builtin/apply: make add_index_file() return -1 on error ...
2016-09-12Merge branch 'rs/compat-strdup'Libravatar Junio C Hamano1-0/+8
* rs/compat-strdup: compat: move strdup(3) replacement to its own file
2016-09-12Merge branch 'jk/squelch-false-warning-from-gcc-o3'Libravatar Junio C Hamano1-0/+1
* jk/squelch-false-warning-from-gcc-o3: color_parse_mem: initialize "struct color" temporary error_errno: use constant return similar to error()
2016-09-07usage: add get_error_routine() and get_warn_routine()Libravatar Christian Couder1-0/+2
Let's make it possible to get the current error_routine and warn_routine, so that we can store them before using set_error_routine() or set_warn_routine() to use new ones. This way we will be able put back the original routines, when we are done with using new ones. Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-07usage: add set_warn_routine()Libravatar Christian Couder1-0/+1
There are already set_die_routine() and set_error_routine(), so let's add set_warn_routine() as this will be needed in a following commit. Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-07compat: move strdup(3) replacement to its own fileLibravatar René Scharfe1-0/+8
Move our implementation of strdup(3) out of compat/nedmalloc/ and allow it to be used independently from USE_NED_ALLOCATOR. The original nedmalloc doesn't come with strdup() and doesn't need it. Only _users_ of nedmalloc need it, which was added when we imported it to our compat/ hierarchy. This reduces the difference of our copy of nedmalloc from the original, making it easier to update, and allows for easier testing and reusing of our version of strdup(). Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-08-31error_errno: use constant return similar to error()Libravatar Jeff King1-0/+1
Commit e208f9c (make error()'s constant return value more visible, 2012-12-15) introduced some macro trickery to make the constant return from error() more visible to callers, which in turn can help gcc produce better warnings (and possibly even better code). Later, fd1d672 (usage.c: add warning_errno() and error_errno(), 2016-05-08) introduced another variant, and subsequent commits converted some uses of error() to error_errno(), losing the magic from e208f9c for those sites. As a result, compiling vcs-svn/svndiff.c with "gcc -O3" produces -Wmaybe-uninitialized false positives (at least with gcc 6.2.0). Let's give error_errno() the same treatment, which silences these warnings. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-08-25Merge branch 'bw/mingw-avoid-inheriting-fd-to-lockfile'Libravatar Junio C Hamano1-0/+4
The tempfile (hence its user lockfile) API lets the caller to open a file descriptor to a temporary file, write into it and then finalize it by first closing the filehandle and then either removing or renaming the temporary file. When the process spawns a subprocess after obtaining the file descriptor, and if the subprocess has not exited when the attempt to remove or rename is made, the last step fails on Windows, because the subprocess has the file descriptor still open. Open tempfile with O_CLOEXEC flag to avoid this (on Windows, this is mapped to O_NOINHERIT). * bw/mingw-avoid-inheriting-fd-to-lockfile: mingw: ensure temporary file handles are not inherited by child processes t6026-merge-attr: child processes must not inherit index.lock handles
2016-08-23mingw: ensure temporary file handles are not inherited by child processesLibravatar Ben Wijen1-0/+4
When the index is locked and child processes inherit the handle to said lock and the parent process wants to remove the lock before the child process exits, on Windows there is a problem: it won't work because files cannot be deleted if a process holds a handle on them. The symptom: Rename from 'xxx/.git/index.lock' to 'xxx/.git/index' failed. Should I try again? (y/n) Spawning child processes with bInheritHandles==FALSE would not work because no file handles would be inherited, not even the hStdXxx handles in STARTUPINFO (stdin/stdout/stderr). Opening every file with O_NOINHERIT does not work, either, as e.g. git-upload-pack expects inherited file handles. This leaves us with the only way out: creating temp files with the O_NOINHERIT flag. This flag is Windows-specific, however. For our purposes, it is equivalent to O_CLOEXEC (which does not exist on Windows), so let's just open temporary files with the O_CLOEXEC flag and map that flag to O_NOINHERIT on Windows. As Eric Wong pointed out, we need to be careful to handle the case where the Linux headers used to compile Git support O_CLOEXEC but the Linux kernel used to run Git does not: it returns an EINVAL. This fixes the test that we just introduced to demonstrate the problem. Signed-off-by: Ben Wijen <ben@wijen.net> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-08-17Merge branch 'jk/tighten-alloc'Libravatar Junio C Hamano1-1/+1
Small code and comment clean-up. * jk/tighten-alloc: receive-pack: use FLEX_ALLOC_MEM in queue_command() correct FLEXPTR_* example in comment
2016-08-13correct FLEXPTR_* example in commentLibravatar René Scharfe1-1/+1
This section is about "The FLEXPTR_* variants", so use FLEXPTR_ALLOC_STR in the example. Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-07-19Merge branch 'jk/common-main'Libravatar Junio C Hamano1-0/+2
There are certain house-keeping tasks that need to be performed at the very beginning of any Git program, and programs that are not built-in commands had to do them exactly the same way as "git" potty does. It was easy to make mistakes in one-off standalone programs (like test helpers). A common "main()" function that calls cmd_main() of individual program has been introduced to make it harder to make mistakes. * jk/common-main: mingw: declare main()'s argv as const common-main: call git_setup_gettext() common-main: call restore_sigpipe_to_default() common-main: call sanitize_stdfds() common-main: call git_extract_argv0_path() add an extra level of indirection to main()
2016-07-11Merge branch 'jk/ansi-color'Libravatar Junio C Hamano1-0/+17
The output coloring scheme learned two new attributes, italic and strike, in addition to existing bold, reverse, etc. * jk/ansi-color: color: support strike-through attribute color: support "italic" attribute color: allow "no-" for negating attributes color: refactor parse_attr add skip_prefix_mem helper doc: refactor description of color format color: fix max-size comment
2016-07-06Merge branch 'jk/common-main-2.8' into jk/common-mainLibravatar Junio C Hamano1-0/+2
* jk/common-main-2.8: mingw: declare main()'s argv as const common-main: call git_setup_gettext() common-main: call restore_sigpipe_to_default() common-main: call sanitize_stdfds() common-main: call git_extract_argv0_path() add an extra level of indirection to main()
2016-07-01add an extra level of indirection to main()Libravatar Jeff King1-0/+2
There are certain startup tasks that we expect every git process to do. In some cases this is just to improve the quality of the program (e.g., setting up gettext()). In others it is a requirement for using certain functions in libgit.a (e.g., system_path() expects that you have called git_extract_argv0_path()). Most commands are builtins and are covered by the git.c version of main(). However, there are still a few external commands that use their own main(). Each of these has to remember to include the correct startup sequence, and we are not always consistent. Rather than just fix the inconsistencies, let's make this harder to get wrong by providing a common main() that can run this standard startup. We basically have two options to do this: - the compat/mingw.h file already does something like this by adding a #define that replaces the definition of main with a wrapper that calls mingw_startup(). The upside is that the code in each program doesn't need to be changed at all; it's rewritten on the fly by the preprocessor. The downside is that it may make debugging of the startup sequence a bit more confusing, as the preprocessor is quietly inserting new code. - the builtin functions are all of the form cmd_foo(), and git.c's main() calls them. This is much more explicit, which may make things more obvious to somebody reading the code. It's also more flexible (because of course we have to figure out _which_ cmd_foo() to call). The downside is that each of the builtins must define cmd_foo(), instead of just main(). This patch chooses the latter option, preferring the more explicit approach, even though it is more invasive. We introduce a new file common-main.c, with the "real" main. It expects to call cmd_main() from whatever other objects it is linked against. We link common-main.o against anything that links against libgit.a, since we know that such programs will need to do this setup. Note that common-main.o can't actually go inside libgit.a, as the linker would not pick up its main() function automatically (it has no callers). The rest of the patch is just adjusting all of the various external programs (mostly in t/helper) to use cmd_main(). I've provided a global declaration for cmd_main(), which means that all of the programs also need to match its signature. In particular, many functions need to switch to "const char **" instead of "char **" for argv. This effect ripples out to a few other variables and functions, as well. This makes the patch even more invasive, but the end result is much better. We should be treating argv strings as const anyway, and now all programs conform to the same signature (which also matches the way builtins are defined). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-23add skip_prefix_mem helperLibravatar Jeff King1-0/+17
The skip_prefix function has been very useful for simplifying pointer arithmetic and avoiding repeated magic numbers, but we have no equivalent for length-limited buffers. So we're stuck with: if (3 <= len && skip_prefix(buf, "foo", &buf)) len -= 3; That's not that complicated, but it needs to use magic numbers for the length of the prefix (or else write out strlen("foo"), repeating the string). By using a helper, we can get the string length behind the scenes (and often at compile time for string literals). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-05-17Merge branch 'nd/error-errno'Libravatar Junio C Hamano1-0/+2
The code for warning_errno/die_errno has been refactored and a new error_errno() reporting helper is introduced. * nd/error-errno: (41 commits) wrapper.c: use warning_errno() vcs-svn: use error_errno() upload-pack.c: use error_errno() unpack-trees.c: use error_errno() transport-helper.c: use error_errno() sha1_file.c: use {error,die,warning}_errno() server-info.c: use error_errno() sequencer.c: use error_errno() run-command.c: use error_errno() rerere.c: use error_errno() and warning_errno() reachable.c: use error_errno() mailmap.c: use error_errno() ident.c: use warning_errno() http.c: use error_errno() and warning_errno() grep.c: use error_errno() gpg-interface.c: use error_errno() fast-import.c: use error_errno() entry.c: use error_errno() editor.c: use error_errno() diff-no-index.c: use error_errno() ...
2016-05-09usage.c: add warning_errno() and error_errno()Libravatar Nguyễn Thái Ngọc Duy1-0/+2
Similar to die_errno(), these functions will append strerror() automatically. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-05-06Merge branch 'ky/imap-send-openssl-1.1.0' into maintLibravatar Junio C Hamano1-3/+0
Upcoming OpenSSL 1.1.0 will break compilation b updating a few APIs we use in imap-send, which has been adjusted for the change. * ky/imap-send-openssl-1.1.0: configure: remove checking for HMAC_CTX_cleanup imap-send: avoid deprecated TLSv1_method() imap-send: check NULL return of SSL_CTX_new() imap-send: use HMAC() function provided by OpenSSL
2016-04-22Merge branch 'ky/imap-send-openssl-1.1.0'Libravatar Junio C Hamano1-3/+0
Upcoming OpenSSL 1.1.0 will break compilation b updating a few APIs we use in imap-send, which has been adjusted for the change. * ky/imap-send-openssl-1.1.0: configure: remove checking for HMAC_CTX_cleanup imap-send: avoid deprecated TLSv1_method() imap-send: check NULL return of SSL_CTX_new() imap-send: use HMAC() function provided by OpenSSL
2016-04-08configure: remove checking for HMAC_CTX_cleanupLibravatar Kazuki Yamaguchi1-3/+0
We don't need it, as we no longer use HMAC_CTX_cleanup() directly. Signed-off-by: Kazuki Yamaguchi <k@rhe.jp> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-03-21Merge branch 'es/st-add4-gcc-4.2-workaround' into maintLibravatar Junio C Hamano1-2/+2
* es/st-add4-gcc-4.2-workaround: git-compat-util: st_add4: work around gcc 4.2.x compiler crash
2016-03-21git-compat-util: st_add4: work around gcc 4.2.x compiler crashLibravatar Eric Sunshine1-2/+2
Although changes by 5b442c4 (tree-diff: catch integer overflow in combine_diff_path allocation, 2016-02-19) are perfectly valid, they unfortunately trigger an internal compiler error in gcc 4.2.x: combine-diff.c: In function 'diff_tree_combined': combine-diff.c:1391: internal compiler error: Segmentation fault: 11 Experimentation reveals that changing st_add4()'s argument evaluation order is sufficient to sidestep this problem. Although st_add3() does not trigger the compiler bug, for style consistency, change its argument evaluation order to match. Signed-off-by: Eric Sunshine <sunshine@sunshineco.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-03-17Merge branch 'maint-2.5' into maint-2.6Libravatar Junio C Hamano1-0/+34
* maint-2.5: Git 2.5.5 Git 2.4.11 list-objects: pass full pathname to callbacks list-objects: drop name_path entirely list-objects: convert name_path to a strbuf show_object_with_name: simplify by using path_name() http-push: stop using name_path tree-diff: catch integer overflow in combine_diff_path allocation add helpers for detecting size_t overflow
2016-03-17Merge branch 'maint-2.4' into maint-2.5Libravatar Junio C Hamano1-0/+34
* maint-2.4: Git 2.4.11 list-objects: pass full pathname to callbacks list-objects: drop name_path entirely list-objects: convert name_path to a strbuf show_object_with_name: simplify by using path_name() http-push: stop using name_path tree-diff: catch integer overflow in combine_diff_path allocation add helpers for detecting size_t overflow
2016-03-16add helpers for detecting size_t overflowLibravatar Jeff King1-0/+34
Performing computations on size_t variables that we feed to xmalloc and friends can be dangerous, as an integer overflow can cause us to allocate a much smaller chunk than we realized. We already have unsigned_add_overflows(), but let's add unsigned_mult_overflows() to that. Furthermore, rather than have each site manually check and die on overflow, we can provide some helpers that will: - promote the arguments to size_t, so that we know we are doing our computation in the same size of integer that will ultimately be fed to xmalloc - check and die on overflow - return the result so that computations can be done in the parameter list of xmalloc. These functions are a lot uglier to use than normal arithmetic operators (you have to do "st_add(foo, bar)" instead of "foo + bar"). To at least limit the damage, we also provide multi-valued versions. So rather than: st_add(st_add(a, b), st_add(c, d)); you can write: st_add4(a, b, c, d); This isn't nearly as elegant as a varargs function, but it's a lot harder to get it wrong. You don't have to remember to add a sentinel value at the end, and the compiler will complain if you get the number of arguments wrong. This patch adds only the numbered variants required to convert the current code base; we can easily add more later if needed. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-03-10Merge branch 'ak/git-strip-extension-from-dashed-command' into maintLibravatar Junio C Hamano1-4/+0
Code simplification. * ak/git-strip-extension-from-dashed-command: git.c: simplify stripping extension of a file in handle_builtin()
2016-02-22git-compat-util: drop mempcpy compat codeLibravatar Jeff King1-9/+0
There are no callers of this left, as the last one was dropped in the previous patch. And there are not likely to be new ones, as the function has been around since 2010 without gaining any new callers. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22add helpers for allocating flex-array structsLibravatar Jeff King1-0/+62
Allocating a struct with a flex array is pretty simple in practice: you over-allocate the struct, then copy some data into the over-allocation. But it can be a slight pain to make sure you're allocating and copying the right amounts. This patch adds a few helpers to turn simple cases of flex-array struct allocation into a one-liner that properly checks for overflow. See the embedded documentation for details. Ideally we could provide a more flexible version that could handle multiple strings, like: FLEX_ALLOC_FMT(ref, name, "%s%s", prefix, name); But we have to implement this as a macro (because of the offset calculation of the flex member), which means we would need all compilers to support variadic macros. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22harden REALLOC_ARRAY and xcalloc against size_t overflowLibravatar Jeff King1-1/+2
REALLOC_ARRAY inherently involves a multiplication which can overflow size_t, resulting in a much smaller buffer than we think we've allocated. We can easily harden it by using st_mult() to check for overflow. Likewise, we can add ALLOC_ARRAY to do the same thing for xmalloc calls. xcalloc() should already be fine, because it takes the two factors separately, assuming the system calloc actually checks for overflow. However, before we even hit the system calloc(), we do our memory_limit_check, which involves a multiplication. Let's check for overflow ourselves so that this limit cannot be bypassed. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-21git.c: simplify stripping extension of a file in handle_builtin()Libravatar Alexander Kuleshov1-4/+0
The handle_builtin() starts from stripping of command extension if STRIP_EXTENSION is enabled. Actually STRIP_EXTENSION does not used anywhere else. This patch introduces strip_extension() helper to strip STRIP_EXTENSION extension from argv[0] with the strip_suffix() instead of manually stripping. Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com> Helped-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-19add helpers for detecting size_t overflowLibravatar Jeff King1-0/+34
Performing computations on size_t variables that we feed to xmalloc and friends can be dangerous, as an integer overflow can cause us to allocate a much smaller chunk than we realized. We already have unsigned_add_overflows(), but let's add unsigned_mult_overflows() to that. Furthermore, rather than have each site manually check and die on overflow, we can provide some helpers that will: - promote the arguments to size_t, so that we know we are doing our computation in the same size of integer that will ultimately be fed to xmalloc - check and die on overflow - return the result so that computations can be done in the parameter list of xmalloc. These functions are a lot uglier to use than normal arithmetic operators (you have to do "st_add(foo, bar)" instead of "foo + bar"). To at least limit the damage, we also provide multi-valued versions. So rather than: st_add(st_add(a, b), st_add(c, d)); you can write: st_add4(a, b, c, d); This isn't nearly as elegant as a varargs function, but it's a lot harder to get it wrong. You don't have to remember to add a sentinel value at the end, and the compiler will complain if you get the number of arguments wrong. This patch adds only the numbered variants required to convert the current code base; we can easily add more later if needed. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-05Merge branch 'js/dirname-basename' into maintLibravatar Junio C Hamano1-0/+10
dirname() emulation has been added, as Msys2 lacks it. * js/dirname-basename: mingw: avoid linking to the C library's isalpha() t0060: loosen overly strict expectations t0060: verify that basename() and dirname() work as expected compat/basename.c: provide a dirname() compatibility function compat/basename: make basename() conform to POSIX Refactor skipping DOS drive prefixes
2016-02-05Merge branch 'js/fopen-harder' into maintLibravatar Junio C Hamano1-0/+1
Some codepaths used fopen(3) when opening a fixed path in $GIT_DIR (e.g. COMMIT_EDITMSG) that is meant to be left after the command is done. This however did not work well if the repository is set to be shared with core.sharedRepository and the umask of the previous user is tighter. They have been made to work better by calling unlink(2) and retrying after fopen(3) fails with EPERM. * js/fopen-harder: Handle more file writes correctly in shared repos commit: allow editing the commit message even in shared repos
2016-01-12compat/basename.c: provide a dirname() compatibility functionLibravatar Johannes Schindelin1-0/+2
When there is no `libgen.h` to our disposal, we miss the `dirname()` function. Earlier we added basename() compatibility function for the same reason at e1c06886 (compat: add a basename() compatibility function, 2009-05-31). So far, we only had one user of that function: credential-cache--daemon (which was only compiled when Unix sockets are available, anyway). But now we also have `builtin/am.c` as user, so we need it. Since `dirname()` is a sibling of `basename()`, we simply put our very own `gitdirname()` implementation next to `gitbasename()` and use it if `NO_LIBGEN_H` has been set. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-01-12Refactor skipping DOS drive prefixesLibravatar Johannes Schindelin1-0/+8
Junio noticed that there is an implicit assumption in pretty much all the code calling has_dos_drive_prefix(): it forces all of its callsites to hardcode the knowledge that the DOS drive prefix is always two bytes long. While this assumption is pretty safe, we can still make the code more readable and less error-prone by introducing a function that skips the DOS drive prefix safely. While at it, we change the has_dos_drive_prefix() return value: it now returns the number of bytes to be skipped if there is a DOS drive prefix. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-01-07commit: allow editing the commit message even in shared reposLibravatar Johannes Schindelin1-0/+1
It was pointed out by Yaroslav Halchenko that the file containing the commit message is writable only by the owner, which means that we have to rewrite it from scratch in a shared repository. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>