The difference from the previous version is the use of decltype, as the
implementation of std::result_of in libc++ did not work correctly for
variadic function like open(2).
Original summary:
This function retries an operation if it was interrupted by a signal
(failed with EINTR). It's inspired by the TEMP_FAILURE_RETRY macro in
glibc, but I've turned that into a template function. I've also added a
fail-value argument, to enable the function to be used with e.g.
fopen(3), which is documented to fail for any reason that open(2) can
fail (which includes EINTR).
The main user of this function will be lldb, but there were also a
couple of uses within llvm that I could simplify using this function.
Reviewers: zturner, silvas, joerg
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D33895
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306671 91177308-0d34-0410-b5e6-96231b3b80d8
The fix in r306003 uncovered a pretty fundamental problem that libc++
implementation of std::result_of does not handle the prototype of
open(2) correctly (presumably because it contains ...). This makes the
whole function unusable in its current form, so I am also reverting the
original commit (r305892), which introduced the function, at least until
I figure out a way to solve the libc++ issue.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306005 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This function retries an operation if it was interrupted by a signal
(failed with EINTR). It's inspired by the TEMP_FAILURE_RETRY macro in
glibc, but I've turned that into a template function. I've also added a
fail-value argument, to enable the function to be used with e.g.
fopen(3), which is documented to fail for any reason that open(2) can
fail (which includes EINTR).
The main user of this function will be lldb, but there were also a
couple of uses within llvm that I could simplify using this function.
Reviewers: zturner, silvas, joerg
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D33895
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305892 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This is a follow-up to D25416. It removes all usages of TimeValue from
llvm/Support library (except for the actual TimeValue declaration), and replaces
them with appropriate usages of std::chrono. To facilitate this, I have added
small utility functions for converting time points and durations into appropriate
OS-specific types (FILETIME, struct timespec, ...).
Reviewers: zturner, mehdi_amini
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D25730
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284966 91177308-0d34-0410-b5e6-96231b3b80d8
In the current implementation compiler only prints stack trace
to console after crash. This patch adds saving of minidump
files which contain a useful subset of the information for
further debugging.
Differential Revision: http://reviews.llvm.org/D18216
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@268519 91177308-0d34-0410-b5e6-96231b3b80d8
I am seeing disappointing clang performance on a large PowerPC64
Linux box. GetRandomNumberSeed() does a buffered read from
/dev/urandom to seed its PRNG. As a result we read an entire page
even though we only need 4 bytes.
With every clang task reading a page worth of /dev/urandom we
end up spending a large amount of time stuck on kernel spinlock.
Patch by Anton Blanchard!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255386 91177308-0d34-0410-b5e6-96231b3b80d8
The patch is generated using this command:
tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
-checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
llvm/lib/
Thanks to Eugene Kosov for the original patch!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240137 91177308-0d34-0410-b5e6-96231b3b80d8
We won't link in pthreads if we weren't built with LLVM_ENABLE_THREADS
which means we won't get access to pthread_sigmask. Use sigprocmask
instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219288 91177308-0d34-0410-b5e6-96231b3b80d8
Most Unix-like operating systems guarantee that the file descriptor is
closed after a call to close(2), even if close comes back with EINTR.
For these systems, calling close _again_ will either do nothing or close
some other file descriptor open(2)'d by another thread. (Linux)
However, some operating systems do not have this behavior. They require
at least another call to close(2) before guaranteeing that the
descriptor is closed. (HP-UX)
And some operating systems have an unpredictable blend of the two
behaviors! (xnu)
Avoid this disaster by blocking all signals before we call close(2).
This ensures that a signal will not be delivered to the thread and
close(2) will not give us back EINTR. We restore the signal mask once
the operation is done.
N.B. This isn't a problem on Windows, it doesn't have a notion of EINTR
because signals always get delivered to dedicated signal handling
threads.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219189 91177308-0d34-0410-b5e6-96231b3b80d8
It's possible to start a program with one (or all) of the standard file
descriptors closed. Subsequent open system calls will give the program
a low-numbered file descriptor.
This is problematic because we may believe we are writing to standard
out instead of a file.
Introduce Process::FixupStandardFileDescriptors, a helper function to
remap standard file descriptors to /dev/null if they were closed before
the program started.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219170 91177308-0d34-0410-b5e6-96231b3b80d8
There is no std::error_code::success, so this removes much of the noise
in transitioning to std::error_code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209952 91177308-0d34-0410-b5e6-96231b3b80d8
ISSUE:
On Ubuntu 12.04 LTS, arc4random is provided by libbsd.so, which is a
transitive dependency of libedit. If a system had libedit on it that
was implemented in terms of libbsd.so, then the arc4random test,
previously implemented as a linker test, would succeed with -ledit.
However, on Ubuntu this would also require a #include <bsd/stdlib.h>.
This caused a build breakage on configure-based Ubuntu 12.04 with
libedit installed.
FIX:
This fix changes configure to test for arc4random by searching for it
in the standard header files. On Ubuntu 12.04, this test now properly
fails to find arc4random as it is not defined in the default header
locations. It also tweaks the #define names to match the output of the
header check command, which is slightly different than the linker
function check #defines.
I tested the following scenarios:
(1) Ubuntu 12.04 without the libedit package [did not find arc4random,
as expected]
(2) Ubuntu 12.04 with libedit package [properly did not find
arc4random, as expected]
(3) Ubuntu 12.04 with most recent libedit, custom built, and not
dependent on libbsd.so [properly did not find arc4random, as
expected].
(4) FreeBSD 10.0B1 [properly found arc4random, as expected]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200819 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The MSVCRT deliberately sends main() code-page specific characters.
This isn't too useful to LLVM as we end up converting the arguments to
UTF-16 and subsequently attempt to use the result as, for example, a
file name. Instead, we need to have the ability to access the Unicode
command line and transform it to UTF-8.
This has the distinct advantage over using the MSVC-specific wmain()
function as our entry point because:
- It doesn't work on cygwin.
- It only work on MinGW with caveats and only then on certain versions.
- We get to keep our entry point as main(). :)
N.B. This patch includes fixes to other parts of lib/Support/Windows
s.t. we would be able to take advantage of getting the Unicode paths.
E.G. clang spawning clang -cc1 would want to give it Unicode arguments.
Reviewers: aaron.ballman, Bigcheese, rnk, ruiu
Reviewed By: rnk
CC: llvm-commits, ygao
Differential Revision: http://llvm-reviews.chandlerc.com/D1834
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192069 91177308-0d34-0410-b5e6-96231b3b80d8
In some cases (e.g. when a build system pipes stderr) the Windows console
API cannot be used to color output. For these, provide a way to switch to
ANSI escape codes. This is required for Clang's -fansi-escape-codes option.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190460 91177308-0d34-0410-b5e6-96231b3b80d8
On Windows, character encoding of multibyte environment variable varies
depending on settings. The only reliable way to handle it I think is to use
GetEnvironmentVariableW().
GetEnvironmentVariableW() works on wchar_t string, which is on Windows UTF16
string. That's not ideal because we use UTF-8 as the internal encoding in LLVM.
This patch defines a wrapper function which takes and returns UTF-8 string for
GetEnvironmentVariableW().
The wrapper function does not do any conversion and just forwards the argument
to getenv() on Unix.
Differential Revision: http://llvm-reviews.chandlerc.com/D1612
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190423 91177308-0d34-0410-b5e6-96231b3b80d8
Offset in mmap(3) should be aligned to gepagesize(), 64k, or mmap(3) would fail.
TODO: Invetigate places where 4096 would be required as pagesize, or 4096 would satisfy.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188903 91177308-0d34-0410-b5e6-96231b3b80d8
allocated by setupterm. Without this, some folks are seeing leaked
memory whenever this routine is called more than once. Thanks to Craig
Topper for the report.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188615 91177308-0d34-0410-b5e6-96231b3b80d8
curses.h). Finding these headers is next to impossible. For example, on
Debian systems libtinfo-dev provides the terminfo reading library we
want, but *not* term.h. For the header, you have to use libncurses-dev.
And libncursesw-dev provides a *different* term.h in a different
location!
These headers aren't worth it. We want two functions the signatures of
which are clearly spec'ed in sys-v and other documentation. Just declare
them ourselves and call them. This should fix some debian builders and
provide better support for "minimal" debian systems that do want color
autodetection.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188165 91177308-0d34-0410-b5e6-96231b3b80d8
library for color support detection. This still will use a curses
library if that is all we have available on the system. This change
tries to use a smaller subset of the curses library, specifically the
subset that is on some systems split off into a separate library. For
example, if you install ncurses configured --with-tinfo, a 'libtinfo' is
install that provides just the terminfo querying functionality. That
library is now used instead of curses when it is available.
This happens to fix a build error on systems with that library because
when we tried to link ncurses into the binary, we didn't pull tinfo in
as well. =]
It should also provide an easy path for supporting the NetBSD
libterminfo library, but as I don't have access to a NetBSD system I'm
leaving adding that support to those folks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188160 91177308-0d34-0410-b5e6-96231b3b80d8
using it to detect whether or not a terminal supports colors. This
replaces a particularly egregious hack that merely compared the TERM
environment variable to "dumb". That doesn't really translate to
a reasonable experience for users that have actually ensured their
terminal's capabilities are accurately reflected.
This makes testing a terminal for color support somewhat more expensive,
but it is called very rarely anyways. The important fast path when the
output is being piped somewhere is already in place.
The global lock may seem excessive, but the spec for calling into curses
is *terrible*. The whole library is terrible, and I spent quite a bit of
time looking for a better way of doing this before convincing myself
that this was the fundamentally correct way to behave. The damage of the
curses library is very narrowly confined, and we continue to use raw
escape codes for actually manipulating the colors which is a much sane
system than directly using curses here (IMO).
If this causes trouble for folks, please let me know. I've tested it on
Linux and will watch the bots carefully. I've also worked to account for
the variances of curses interfaces that I could finde documentation for,
but that may not have been sufficient.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187874 91177308-0d34-0410-b5e6-96231b3b80d8
leaving this undefined, and despite the sentence in the standard that
seems to require it, I'll cede the point and assume its a bug in the
wording. Other parts of POSIX regularly allow for things to be -1
instead of undefined, this should too. Makes things more consistent too.
This should have to real impact for folks though.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171574 91177308-0d34-0410-b5e6-96231b3b80d8
defines _POSIX_CPUTIME but doesn't support the clock_* functions.
I don't test the value of _POSIX_CPUTIME because the spec merely says
that if it is defined, the CPU-specific timers are available, whereas it
says that _POSIX_TIMERS must be defined and defined to a value greater
than zero. However, this may not work, as the POSIX spec clearly states:
"If the symbolic constant _POSIX_CPUTIME is defined, then the symbolic
constant _POSIX_TIMERS shall also be defined by the implementation to
have the value 200112L."
If this doesn't work, I'll add more hacks for Darwin.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171565 91177308-0d34-0410-b5e6-96231b3b80d8
wall time, user time, and system time since a process started.
For walltime, we currently use TimeValue's interface and a global
initializer to compute a close approximation of total process runtime.
For user time, this adds support for an somewhat more precise timing
mechanism -- clock_gettime with the CLOCK_PROCESS_CPUTIME_ID clock
selected.
For system time, we have to do a full getrusage call to extract the
system time from the OS. This is expensive but unavoidable.
In passing, clean up the implementation of the old APIs and fix some
latent bugs in the Windows code. This might have manifested on Windows
ARM systems or other systems with strange 64-bit integer behavior.
The old API for this both user time and system time simultaneously from
a single getrusage call. While this results in fewer system calls, it
also results in a lower precision user time and if only user time is
desired, it introduces a higher overhead. It may be worthwhile to switch
some of the pass timers to not track system time and directly track user
and wall time. The old API also tracked walltime in a confusing way --
it just set it to the current walltime rather than providing any measure
of wall time since the process started the way buth user and system time
are tracked. The new API is more consistent here.
The plan is to eventually implement these methods for a *child* process
by using the wait3(2) system call to populate an rusage struct
representing the whole subprocess execution. That way, after waiting on
a child process its stats will become accurate and cheap to query.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171551 91177308-0d34-0410-b5e6-96231b3b80d8
