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.
llvm-svn: 219170
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]
llvm-svn: 200819
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
llvm-svn: 192069
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.
llvm-svn: 190460
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
llvm-svn: 190423
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.
llvm-svn: 188903
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.
llvm-svn: 188615
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.
llvm-svn: 188165
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.
llvm-svn: 188160
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.
llvm-svn: 187874
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.
llvm-svn: 171574
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.
llvm-svn: 171565
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.
llvm-svn: 171551
Implement the old API in terms of the new one. This simplifies the
implementation on Windows which can now re-use the self_process's once
initialization.
llvm-svn: 171330
Fix a truly odd namespace qualifier that was flat out wrong in the
process. The fully qualified namespace would have been
llvm::sys::TimeValue, llvm::TimeValue makes no sense.
llvm-svn: 171292
The coding style used here is not LLVM's style because this is modeled
after a Boost interface and thus done in the style of a candidate C++
standard library interface. I'll probably end up proposing it as
a standard C++ library if it proves to be reasonably portable and
useful.
This is just the most basic parts of the interface -- getting the
process ID out of it. However, it helps sketch out some of the boiler
plate such as the base class, derived class, shared code, and static
factory function. It also introduces a unittest so that I can
incrementally ensure this stuff works.
However, I've not even compiled this code for Windows yet. I'll try to
fix any Windows fallout from the bots, and if I can't fix it I'll revert
and get someone on Windows to help out. There isn't a lot more that is
mandatory, so soon I'll switch to just stubbing out the Windows side and
get Michael Spencer to help with implementation as he can test it
directly.
llvm-svn: 171289
or Clang is using this, and it would be hard to use it correctly given
the thread hostility of the function. Also, it never checked the return
which is rather dangerous with chdir. If someone was in fact using this,
please let me know, as well as what the usecase actually is so that
I can add it back and make it more correct and secure to use. (That
said, it's never going to be "safe" per-se, but we could at least
document the risks...)
llvm-svn: 148211
David Majnemer