Add a FREE_AND_NULL() wrapper marco for the common pattern of freeing
a pointer and assigning NULL to it right afterwards.
The implementation is similar to the (currently unused) XDL_PTRFREE
macro in xdiff/xmacros.h added in commit 3443546f6e ("Use a *real*
built-in diff generator", 2006-03-24). The only difference is that
free() is called unconditionally, see [1].
See [2] for a suggested alternative which does this via a function
instead of a macro. As covered in replies to that message, while it's
a viable approach, it would introduce caveats which this approach
doesn't have, so that potential change is left to a future follow-up
change.
This merely allows us to translate exactly what we're doing now to a
less verbose & idiomatic form using a macro, while guaranteeing that
we don't introduce any functional changes.
1. <alpine.DEB.2.20.1608301948310.129229@virtualbox>
(http://public-inbox.org/git/alpine.DEB.2.20.1608301948310.129229@virtualbox/)
2. <20170610032143.GA7880@starla>
(https://public-inbox.org/git/20170610032143.GA7880@starla/)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We often try to open a file for reading whose existence is
optional, and silently ignore errors from open/fopen; report such
errors if they are not due to missing files.
* nd/fopen-errors:
mingw_fopen: report ENOENT for invalid file names
mingw: verify that paths are not mistaken for remote nicknames
log: fix memory leak in open_next_file()
rerere.c: move error_errno() closer to the source system call
print errno when reporting a system call error
wrapper.c: make warn_on_inaccessible() static
wrapper.c: add and use fopen_or_warn()
wrapper.c: add and use warn_on_fopen_errors()
config.mak.uname: set FREAD_READS_DIRECTORIES for Darwin, too
config.mak.uname: set FREAD_READS_DIRECTORIES for Linux and FreeBSD
clone: use xfopen() instead of fopen()
use xfopen() in more places
git_fopen: fix a sparse 'not declared' warning
Our code often opens a path to an optional file, to work on its
contents when we can successfully open it. We can ignore a failure
to open if such an optional file does not exist, but we do want to
report a failure in opening for other reasons (e.g. we got an I/O
error, or the file is there, but we lack the permission to open).
The exact errors we need to ignore are ENOENT (obviously) and
ENOTDIR (less obvious). Instead of repeating comparison of errno
with these two constants, introduce a helper function to do so.
* jc/noent-notdir:
treewide: use is_missing_file_error() where ENOENT and ENOTDIR are checked
compat-util: is_missing_file_error()
The "run-command" API implementation has been made more robust
against dead-locking in a threaded environment.
* bw/forking-and-threading:
usage.c: drop set_error_handle()
run-command: restrict PATH search to executable files
run-command: expose is_executable function
run-command: block signals between fork and execve
run-command: add note about forking and threading
run-command: handle dup2 and close errors in child
run-command: eliminate calls to error handling functions in child
run-command: don't die in child when duping /dev/null
run-command: prepare child environment before forking
string-list: add string_list_remove function
run-command: use the async-signal-safe execv instead of execvp
run-command: prepare command before forking
t0061: run_command executes scripts without a #! line
t5550: use write_script to generate post-update hook
Our code often opens a path to an optional file, to work on its
contents when we can successfully open it. We can ignore a failure
to open if such an optional file does not exist, but we do want to
report a failure in opening for other reasons (e.g. we got an I/O
error, or the file is there, but we lack the permission to open).
The exact errors we need to ignore are ENOENT (obviously) and
ENOTDIR (less obvious). Instead of repeating comparison of errno
with these two constants, introduce a helper function to do so.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Introduce the BUG() macro to improve die("BUG: ...").
* jk/bug-to-abort:
usage: add NORETURN to BUG() function definitions
config: complain about --local outside of a git repo
setup_git_env: convert die("BUG") to BUG()
usage.c: add BUG() function
After the last patch, this function is not used outside anymore. Keep it
static.
Noticed-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When fopen() returns NULL, it could be because the given path does not
exist, but it could also be some other errors and the caller has to
check. Add a wrapper so we don't have to repeat the same error check
everywhere.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In many places, Git warns about an inaccessible file after a fopen()
failed. To discern these cases from other cases where we want to warn
about inaccessible files, introduce a new helper specifically to test
whether fopen() failed because the current user lacks the permission to
open file in question.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If git is built with the FREAD_READS_DIRECTORIES build variable set, this
would cause sparse to issue a 'not declared, should it be static?' warning
on Linux. This is a result of the method employed by 'compat/fopen.c' to
suppress the (possible) redefinition of the (system) fopen macro, which
also removes the extern declaration of the git_fopen function.
In order to suppress the warning, introduce a new macro to suppress the
definition (or possibly the re-definition) of the fopen symbol as a macro
override. This new macro (SUPPRESS_FOPEN_REDEFINITION) is only defined in
'compat/fopen.c', just prior to the inclusion of the 'git-compat-util.h'
header file.
Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some platforms have ulong that is smaller than time_t, and our
historical use of ulong for timestamp would mean they cannot
represent some timestamp that the platform allows. Invent a
separate and dedicated timestamp_t (so that we can distingiuish
timestamps and a vanilla ulongs, which along is already a good
move), and then declare uintmax_t is the type to be used as the
timestamp_t.
* js/larger-timestamps:
archive-tar: fix a sparse 'constant too large' warning
use uintmax_t for timestamps
date.c: abort if the system time cannot handle one of our timestamps
timestamp_t: a new data type for timestamps
PRItime: introduce a new "printf format" for timestamps
parse_timestamp(): specify explicitly where we parse timestamps
t0006 & t5000: skip "far in the future" test when time_t is too limited
t0006 & t5000: prepare for 64-bit timestamps
ref-filter: avoid using `unsigned long` for catch-all data type
The default packed-git limit value has been raised on larger
platforms to save "git fetch" from a (recoverable) failure while
"gc" is running in parallel.
* dt/raise-core-packed-git-limit:
Increase core.packedGitLimit
The set_error_handle() function was introduced by 3b331e926
(vreportf: report to arbitrary filehandles, 2015-08-11) so
that run-command could send post-fork, pre-exec errors to
the parent's original stderr.
That use went away in 79319b194 (run-command: eliminate
calls to error handling functions in child, 2017-04-19),
which pushes all of the error reporting to the parent.
This leaves no callers of set_error_handle(). As we're not
likely to add any new ones, let's drop it.
Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Brandon Williams <bmwill@google.com>
Reviewed-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There's a convention in Git's code base to write assertions
as:
if (...some_bad_thing...)
die("BUG: the terrible thing happened");
with the idea that users should never see a "BUG:" message
(but if they, it at least gives a clue what happened). We
use die() here because it's convenient, but there are a few
draw-backs:
1. Without parsing the messages, it's hard for callers to
distinguish BUG assertions from regular errors.
For instance, it would be nice if the test suite could
check that we don't hit any assertions, but
test_must_fail will pass BUG deaths as OK.
2. It would be useful to add more debugging features to
BUG assertions, like file/line numbers or dumping core.
3. The die() handler can be replaced, and might not
actually exit the whole program (e.g., it may just
pthread_exit()). This is convenient for normal errors,
but for an assertion failure (which is supposed to
never happen), we're probably better off taking down
the whole process as quickly and cleanly as possible.
We could address these by checking in die() whether the
error message starts with "BUG", and behaving appropriately.
But there's little advantage at that point to sharing the
die() code, and only downsides (e.g., we can't change the
BUG() interface independently). Moreover, converting all of
the existing BUG calls reveals that the test suite does
indeed trigger a few of them.
Instead, this patch introduces a new BUG() function, which
prints an error before dying via SIGABRT. This gives us test
suite checking and core dumps. The function is actually a
macro (when supported) so that we can show the file/line
number.
We can convert die("BUG") invocations to BUG() in further
patches, dealing with any test fallouts individually.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Previously, we used `unsigned long` for timestamps. This was only a good
choice on Linux, where we know implicitly that `unsigned long` is what is
used for `time_t`.
However, we want to use a different data type for timestamps for two
reasons:
- there is nothing that says that `unsigned long` should be the same data
type as `time_t`, and indeed, on 64-bit Windows for example, it is not:
`unsigned long` is 32-bit but `time_t` is 64-bit.
- even on 32-bit Linux, where `unsigned long` (and thereby `time_t`) is
32-bit, we *want* to be able to encode timestamps in Git that are
currently absurdly far in the future, *even if* the system library is
not able to format those timestamps into date strings.
So let's just switch to the maximal integer type available, which should
be at least 64-bit for all practical purposes these days. It certainly
cannot be worse than `unsigned long`, so...
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git's source code assumes that unsigned long is at least as precise as
time_t. Which is incorrect, and causes a lot of problems, in particular
where unsigned long is only 32-bit (notably on Windows, even in 64-bit
versions).
So let's just use a more appropriate data type instead. In preparation
for this, we introduce the new `timestamp_t` data type.
By necessity, this is a very, very large patch, as it has to replace all
timestamps' data type in one go.
As we will use a data type that is not necessarily identical to `time_t`,
we need to be very careful to use `time_t` whenever we interact with the
system functions, and `timestamp_t` everywhere else.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
gethostname(2) may not NUL terminate the buffer if hostname does
not fit; unfortunately there is no easy way to see if our buffer
was too small, but at least this will make sure we will not end up
using garbage past the end of the buffer.
* dt/xgethostname-nul-termination:
xgethostname: handle long hostnames
use HOST_NAME_MAX to size buffers for gethostname(2)
Currently, Git's source code treats all timestamps as if they were
unsigned longs. Therefore, it is okay to write "%lu" when printing them.
There is a substantial problem with that, though: at least on Windows,
time_t is *larger* than unsigned long, and hence we will want to switch
away from the ill-specified `unsigned long` data type.
So let's introduce the pseudo format "PRItime" (currently simply being
defined to "lu") to make it easier to change the data type used for
timestamps.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently, Git's source code represents all timestamps as `unsigned
long`. In preparation for using a more appropriate data type, let's
introduce a symbol `parse_timestamp` (currently being defined to
`strtoul`) where appropriate, so that we can later easily switch to,
say, use `strtoull()` instead.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When core.packedGitLimit is exceeded, git will close packs. If there
is a repack operation going on in parallel with a fetch, the fetch
might open a pack, and then be forced to close it due to
packedGitLimit being hit. The repack could then delete the pack
out from under the fetch, causing the fetch to fail.
Increase core.packedGitLimit's default value to prevent
this.
On current 64-bit x86_64 machines, 48 bits of address space are
available. It appears that 64-bit ARM machines have no standard
amount of address space (that is, it varies by manufacturer), and IA64
and POWER machines have the full 64 bits. So 48 bits is the only
limit that we can reasonably care about. We reserve a few bits of the
48-bit address space for the kernel's use (this is not strictly
necessary, but it's better to be safe), and use up to the remaining
45. No git repository will be anywhere near this large any time soon,
so this should prevent the failure.
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: David Turner <dturner@twosigma.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If the full hostname doesn't fit in the buffer supplied to
gethostname, POSIX does not specify whether the buffer will be
null-terminated, so to be safe, we should do it ourselves. Introduce
new function, xgethostname, which ensures that there is always a \0
at the end of the buffer.
Signed-off-by: David Turner <dturner@twosigma.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
POSIX limits the length of host names to HOST_NAME_MAX. Export the
fallback definition from daemon.c and use this constant to make all
buffers used with gethostname(2) big enough for any possible result
and a terminating NUL.
Inspired-by: David Turner <dturner@twosigma.com>
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: David Turner <dturner@twosigma.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Code clean-up.
* jk/pack-name-cleanups:
index-pack: make pointer-alias fallbacks safer
replace snprintf with odb_pack_name()
odb_pack_keep(): stop generating keepfile name
sha1_file.c: make pack-name helper globally accessible
move odb_* declarations out of git-compat-util.h
Code clean-up.
* jk/pack-name-cleanups:
index-pack: make pointer-alias fallbacks safer
replace snprintf with odb_pack_name()
odb_pack_keep(): stop generating keepfile name
sha1_file.c: make pack-name helper globally accessible
move odb_* declarations out of git-compat-util.h
These functions were originally conceived as wrapper
functions similar to xmkstemp(). They were later moved by
463db9b10 (wrapper: move odb_* to environment.c,
2010-11-06). The more appropriate place for a declaration is
in cache.h.
While we're at it, let's add some basic docstrings.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The last call to the mkstemps() function was removed in commit 659488326
("wrapper.c: delete dead function git_mkstemps()", 22-04-2016). In order
to support platforms without mkstemps(), this functionality was provided,
along with a Makefile build variable (NO_MKSTEMPS), by the gitmkstemps()
function. Remove the dead code, along with the defunct build machinery.
Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a macro for exchanging the values of variables. It allows users
to avoid repetition and takes care of the temporary variable for them.
It also makes sure that the storage sizes of its two parameters are the
same. Its memcpy(1) calls are optimized away by current compilers.
Also add a conservative semantic patch for transforming only swaps of
variables of the same type.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
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>
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>
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>
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>
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
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
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>
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
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>
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>
"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
...
