Commit graph

410 commits

Author SHA1 Message Date
Junio C Hamano cd1c2e7301 Merge branch 'jk/common-main' into maint-2.10
* jk/common-main:
  common-main: stop munging argv[0] path
  git-compat-util: move content inside ifdef/endif guards
2016-12-05 11:24:28 -08:00
Junio C Hamano 63cf124c24 Merge branch 'jk/tighten-alloc' into maint
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
2016-10-28 09:01:18 -07:00
Jeff King 5c238e29a8 git-compat-util: move content inside ifdef/endif guards
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>
2016-10-27 10:36:45 -07:00
René Scharfe 0ac52a38e8 inline xalloc_flex() into FLEXPTR_ALLOC_MEM
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>
2016-10-17 14:42:56 -07:00
René Scharfe e9451782cf avoid pointer arithmetic involving NULL in FLEX_ALLOC_MEM
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>
2016-10-17 14:42:31 -07:00
Junio C Hamano a813b19190 Merge branch 'rs/copy-array' into maint
Code cleanup.

* rs/copy-array:
  use COPY_ARRAY
  add COPY_ARRAY
2016-10-11 14:18:32 -07:00
Junio C Hamano 300e95f7df Merge branch 'js/regexec-buf' into maint
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
2016-09-29 16:49:45 -07:00
René Scharfe 60566cbb58 add COPY_ARRAY
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>
2016-09-25 16:44:12 -07:00
Johannes Schindelin 2f8952250a regex: add regexec_buf() that can work on a non NUL-terminated string
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>
2016-09-21 13:56:15 -07:00
Junio C Hamano 815a73f714 Merge branch 'rs/compat-strdup' into maint
Code cleanup.

* rs/compat-strdup:
  compat: move strdup(3) replacement to its own file
2016-09-19 13:51:42 -07:00
Junio C Hamano 3d54b93f40 Merge branch 'jk/squelch-false-warning-from-gcc-o3' into maint
Compilation fix.

* jk/squelch-false-warning-from-gcc-o3:
  color_parse_mem: initialize "struct color" temporary
  error_errno: use constant return similar to error()
2016-09-19 13:51:41 -07:00
René Scharfe ca2baa3f75 compat: move strdup(3) replacement to its own file
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>
2016-09-07 10:41:45 -07:00
Jeff King 4df5e91867 error_errno: use constant return similar to error()
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>
2016-08-31 11:11:54 -07:00
Junio C Hamano 3dc01702df Merge branch 'bw/mingw-avoid-inheriting-fd-to-lockfile'
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
2016-08-25 13:55:07 -07:00
Ben Wijen 05d1ed6148 mingw: ensure temporary file handles are not inherited by child processes
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>
2016-08-23 09:09:55 -07:00
Junio C Hamano 2f664566c5 Merge branch 'jk/tighten-alloc'
Small code and comment clean-up.

* jk/tighten-alloc:
  receive-pack: use FLEX_ALLOC_MEM in queue_command()
  correct FLEXPTR_* example in comment
2016-08-17 14:07:46 -07:00
René Scharfe 0bb1519f05 correct FLEXPTR_* example in comment
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>
2016-08-13 19:44:03 -07:00
Junio C Hamano d4c6375fd8 Merge branch 'jk/common-main'
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()
2016-07-19 13:22:19 -07:00
Junio C Hamano 3c5de5c77b Merge branch 'jk/ansi-color'
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
2016-07-11 10:31:05 -07:00
Junio C Hamano de61cebde7 Merge branch 'jk/common-main-2.8' into jk/common-main
* 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()
2016-07-06 10:02:57 -07:00
Jeff King 3f2e2297b9 add an extra level of indirection to main()
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>
2016-07-01 15:09:10 -07:00
Jeff King ae989a61da add skip_prefix_mem helper
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>
2016-06-23 11:32:51 -07:00
Junio C Hamano 40cfc95856 Merge branch 'nd/error-errno'
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()
  ...
2016-05-17 14:38:28 -07:00
Nguyễn Thái Ngọc Duy fd1d672300 usage.c: add warning_errno() and error_errno()
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>
2016-05-09 12:29:08 -07:00
Junio C Hamano a0c9cf51c0 Merge branch 'ky/imap-send-openssl-1.1.0' into maint
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
2016-05-06 14:53:24 -07:00
Junio C Hamano 33e4ec89d9 Merge branch 'ky/imap-send-openssl-1.1.0'
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
2016-04-22 15:45:08 -07:00
Kazuki Yamaguchi 1245c74936 configure: remove checking for HMAC_CTX_cleanup
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>
2016-04-08 11:46:36 -07:00
Junio C Hamano 2ab5c88642 Merge branch 'es/st-add4-gcc-4.2-workaround' into maint
* es/st-add4-gcc-4.2-workaround:
  git-compat-util: st_add4: work around gcc 4.2.x compiler crash
2016-03-21 09:19:27 -07:00
Eric Sunshine d616fbf256 git-compat-util: st_add4: work around gcc 4.2.x compiler crash
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>
2016-03-21 09:18:07 -07:00
Junio C Hamano ce4d4e763c Merge branch 'maint-2.5' into maint-2.6
* 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
2016-03-17 11:26:18 -07:00
Junio C Hamano c638f3e4d5 Merge branch 'maint-2.4' into maint-2.5
* 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
2016-03-17 11:24:14 -07:00
Jeff King 935de81289 add helpers for detecting size_t overflow
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>
2016-03-16 10:41:02 -07:00
Junio C Hamano 08e21c9b5f Merge branch 'ak/git-strip-extension-from-dashed-command' into maint
Code simplification.

* ak/git-strip-extension-from-dashed-command:
  git.c: simplify stripping extension of a file in handle_builtin()
2016-03-10 11:13:48 -08:00
Jeff King 7eb45b5f78 git-compat-util: drop mempcpy compat code
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>
2016-02-22 14:51:09 -08:00
Jeff King 3689539127 add helpers for allocating flex-array structs
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>
2016-02-22 14:50:32 -08:00
Jeff King e7792a74bc harden REALLOC_ARRAY and xcalloc against size_t overflow
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>
2016-02-22 14:50:32 -08:00
Alexander Kuleshov 63ca1c099c git.c: simplify stripping extension of a file in handle_builtin()
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>
2016-02-21 23:52:43 -08:00
Jeff King 320d0b493a add helpers for detecting size_t overflow
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>
2016-02-19 09:40:37 -08:00
Junio C Hamano 07be1da216 Merge branch 'js/dirname-basename' into maint
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
2016-02-05 14:54:17 -08:00
Junio C Hamano da07df3ee3 Merge branch 'js/fopen-harder' into maint
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
2016-02-05 14:54:11 -08:00
Johannes Schindelin 824682ab51 compat/basename.c: provide a dirname() compatibility function
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>
2016-01-12 10:40:54 -08:00
Johannes Schindelin 2f36eed936 Refactor skipping DOS drive prefixes
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>
2016-01-12 10:39:40 -08:00
Johannes Schindelin 79d7582e32 commit: allow editing the commit message even in shared repos
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>
2016-01-07 13:52:55 -08:00
Junio C Hamano 5498c57cdd Merge branch 'jk/ident-loosen-getpwuid'
When getpwuid() on the system returned NULL (e.g. the user is not
in the /etc/passwd file or other uid-to-name mappings), the
codepath to find who the user is to record it in the reflog barfed
and died.  Loosen the check in this codepath, which already accepts
questionable ident string (e.g. host part of the e-mail address is
obviously bogus), and in general when we operate fmt_ident() function
in non-strict mode.

* jk/ident-loosen-getpwuid:
  ident: loosen getpwuid error in non-strict mode
  ident: keep a flag for bogus default_email
  ident: make xgetpwuid_self() a static local helper
2015-12-21 10:59:07 -08:00
Jeff King e850194c83 ident: make xgetpwuid_self() a static local helper
This function is defined in wrapper.c, but nobody besides
ident.c uses it. And nobody is likely to in the future,
either, as anything that cares about the user's name should
be going through the ident code.

Moving it here is a cleanup of the global namespace, but it
will also enable further cleanups inside ident.c.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-12-10 15:38:59 -08:00
Junio C Hamano ace5348dcb Merge branch 'js/misc-fixes' into maint
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
2015-11-05 12:18:13 -08:00
Junio C Hamano 808d119263 Merge branch 'js/misc-fixes'
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
2015-10-30 13:07:00 -07:00
Waldek Maleska fdcdb77855 Correct fscanf formatting string for I64u values
This fix is probably purely cosmetic because PRIuMAX is likely identical
to SCNuMAX. Nevertheless, when using a function of the scanf() family,
the correct interpolation to use is the latter, not the former.

Signed-off-by: Waldek Maleska <w.maleska@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-26 13:24:03 -07:00
Johannes Schindelin 8f77442358 Squelch warning about an integer overflow
We cannot rely on long integers to have more than 32 bits.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-10-26 13:23:59 -07:00
Junio C Hamano 78891795df Merge branch 'jk/war-on-sprintf'
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
  ...
2015-10-20 15:24:01 -07:00