Rather than waiting for signalfd_select_wait in a thread, which is racy,
create a global event "my_pendingsigs_evt" which is set and reset by
wait_sig depending only on the fact if blocked signals are pending or not.
This in turn allows to WFMO on this event in select as soon as signalfds
are present in the read descriptor set. Select's peek and verify
will then check if one of the present signalfds is affected.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
So far sig_send's return type is int. The problem with this is
that sig_send returns a sigset_t on __SIGPENDING, and sigset_t
is defined as long type. So the function only returns the lower
32 bit of sigset_t, which is fine on 32 bit, but casts away the
pending RT signals on 64 bit.
Fix this by changing the return type of sig_send to sigset_t, so
as not to narrow down the sigset when returning from handling
__SIGPENDING. Make sure to cast correctly in all invocations
of sig_send.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
POSIX requires that raise(3) is equivalent to
pthread_kill(pthread_self(), sig);
in multi-threaded applications. Our raise just called kill(sig).
Fix that.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
- Rename files timer.* to posix_timer.*.
- Reimplement using an OS timer rather than a handcrafted wait loop.
- Use a Slim R/W Lock for synchronization.
- Drop timer chaining. It doesn't server a purpose since all timers
are local only.
- Rename ttstart to itimer_tracker to better reflect its purpose.
It's not the anchor for a timer chain anymore anyway.
- Drop fixup_timers_after_fork. Everything is process-local, nothing
gets inherited.
- Rename timer_tracker::disarm_event to disarm_overrun_event for
better readability.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Allow the signal thread to recognize we're called in consequence of
select on a signalfd. If the signal is part of the wait mask, don't
call any signal handler and don't remove the signal from the queue,
so a subsequent read (or sigwaitinfo/sigtimedwait) still gets the
signal. Instead, just signal the event object at
_cygtls::signalfd_select_wait for the thread running select.
The addition of signalfd_select_wait to _cygtls unearthed the alignment
problem of the context member again. To make sure this doesn't get lost,
improve the related comment in the header file so that this (hopefully)
doesn't get lost (again).
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
First cut of a signalfd implementation.
Still TODO: Non-polling select.
This should mostly work as on Linux except for missing support
for some members of struct signalfd_siginfo, namely ssi_fd,
ssi_band (both SIGIO/SIGPOLL, not fully implemented) and ssi_trapno
(HW exception, required HW support).
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
- Drop hires_[nm]s clocks, rename hires.h to clock.h.
- Implement clk_t class as an extensible clock class in new file clock.cc.
- Introduce get_clock(clock_id) returning a pointer to the clk_t instance
for clock_id. Provide the following methods along the lines of the former
hires classes:
void clk_t::nsecs (struct timespec *);
ULONGLONG clk_t::nsecs ();
LONGLONG clk_t::usecs ();
LONGLONG clk_t::msecs ();
void clk_t::resolution (struct timespec *);
- Add CLOCK_REALTIME_COARSE, CLOCK_MONOTONIC_RAW, CLOCK_MONOTONIC_COARSE
and CLOCK_BOOTTIME clocks.
- Allow clock_nanosleep, pthread_condattr_setclock and timer_create to use
all new clocks (both clocks should be usable with a small tweak, though).
- Bump DLL major version to 2.12.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
* Redefine NSPERSEC to NS100PERSEC
* Define NSPERSEC as nanosecs per second
* Define USPERSEC as microsecs per second
* Use above constants throughout where appropriate
* Rename to_us to timespec_to_us and inline
* Rename it_bad to timespec_bad and inline
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
There are two common sigpause variants, both of which take an int argument.
If you request _XOPEN_SOURCE or _GNU_SOURCE, you get the System V version,
which removes the given signal from the process's signal mask; otherwise
you get the BSD version, which sets the process's signal mask to the given
value.
Signed-off-by: Yaakov Selkowitz <yselkowi@redhat.com>
Don't allow signal 0 in signal(2), sigaction(2), siginterrupt(3).
Don't allow any signal in sigqueue(3) but explicitely handle
signal 0 as in kill(2).
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
This is a followup to a report back in 2011 about essentially the same issue:
https://cygwin.com/ml/cygwin/2011-04/msg00031.html
The same test program in that report demonstrates the issue, but with
kill sending any non-zero signal. To reiterate, the problem here is
POSIX compliance with respect to sending signals to zombie processes.
http://pubs.opengroup.org/onlinepubs/9699919799/functions/kill.html
claims:
Existing implementations vary on the result of a kill() with pid
indicating an inactive process (a terminated process that has not been
waited for by its parent). Some indicate success on such a call
(subject to permission checking), while others give an error of
[ESRCH]. Since the definition of process lifetime in this volume of
POSIX.1-2008 covers inactive processes, the [ESRCH] error as described
is inappropriate in this case. In particular, this means that an
application cannot have a parent process check for termination of a
particular child with kill(). (Usually this is done with the null
signal; this can be done reliably with waitpid().)
In response to the originally issue, this was fixed *specifically* for
the case of kill(pid, 0). But my reading of the above is that kill()
should return 0 in this case regardless of the signal (modulo
permissions, etc.). On Linux, for example, when calling kill with pid
of a zombie process the kernel will happily deliver the signal to the
relevant task_struct; it will just never be acted on since the task
will never run again.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Bump GPLv2+ to GPLv3+ for some files, clarify BSD 2-clause.
Everything else stays under GPLv3+.
New Linking Exception exempts resulting executables from LGPLv3 section 4.
Add CONTRIBUTORS file to keep track of licensing.
Remove 'Copyright Red Hat Inc' comments.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
This reverts commit 0008bdea02.
This patch introduced a regression. Calling FOO=$(...) in zsh hangs
indefinitely and has to be killed forcefully.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
G++ 6.0 asserts that the "this" pointer is non-null for member
functions.
Refactor methods that check if "this" is non-null to resolve this.
winsup/cygwin/ChangeLog:
external.cc (cygwin_internal): Check for a null pinfo before calling
cmdline.
fhandler_dsp.cc (Audio::blockSize): Make static.
fhandler_dsp.cc (Audio_in): add default_buf_info.
fhandler_dsp.cc (Audio_out): Ditto.
fhandler_dsp.cc (Audio_out::buf_info): Refactor method to call
default_buf_info if dev_ is null.
fhandler_dsp.cc (Audio_in::buf_info): Ditto.
fhandler_dsp.cc (fhandler_dev_dsp::_ioctl): Call Audio_out::default_buf_info if audio_out_ is null.
fhandler_dsp.cc (fhandler_dev_dsp::_ioctl): Call Audio_in::default_buf_info if audio_in_ is null.
fhandler_process.cc (format_process_fd): Check if pinfo is null.
fhandler_process.cc (format_process_root): Ditto.
fhandler_process.cc (format_process_cwd): Ditto.
fhandler_process.cc (format_process_cmdline): Ditto.
signal.cc (tty_min::kill_pgrp): Ditto.
signal.cc (_pinfo::kill0): Ditto.
sigproc.cc (pid_exists): Ditto.
sigproc.cc (remove_proc): Ditto.
times.cc (clock_gettime): Ditto.
times.cc (clock_getcpuclockid): Ditto.
path.cc (cwdstuff::override_win32_cwd): Check if old_cwd is null.
path.cc (fcwd_access_t::Free): Factor null check of "this" out to
caller(s).
pinfo.cc (_pinfo::exists): Ditto.
pinfo.cc (_pinfo::fd): Ditto.
pinfo.cc (_pinfo::fds): Ditto.
pinfo.cc (_pinfo::root): Ditto.
pinfo.cc (_pinfo::cwd): Ditto.
pinfo.cc (_pinfo::cmdline): Ditto.
signal.cc (_pinfo::kill): Ditto.
pinfo.cc (_pinfo::commune_request): remove non-null check on "this", as
this method is only called from pinfo.cc after null checks
pinfo.cc (_pinfo::pipe_fhandler): remove non-null check on "this", as
this method is only called from pipe.cc (fhandler_pipe::open) after a null check.
Signed-off-by: Peter Foley <pefoley2@pefoley.com>
* signal.cc (sigwait): Fix return value to reflect errno in case of
error according to POSIX. Never return EINTR.
* thread.cc (pthread_kill): Return errno if sig_send failed.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
* exceptions.cc (_cygtls::call_signal_handler): Drop manipulating
thread's ss_flags here. It's not safe against longjmp.
* signal.cc (sigaltstack): Check if we're running on the alternate
stack and set ss_flags returned in oss to SS_ONSTACK.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
handler.
* cygtls.cc (_cygtls::remove): Accommodate the fact that pathbufs
has been moved from _local_storage to _cygtls.
* cygtls.h (class tls_pathbuf): Add comment to hint to gendef usage
of counters. Change type of counters to uint32_t for clarity.
Remove _cygtls as friend class.
(struct _local_storage): Move pathbufs from here...
(struct _cygtls): ...to here, allowing to access it from _sigbe.
(class san): Only define on 32 bit. Remove errno, _c_cnt and _w_cnt
members.
(san::setup): Drop parameter. Don't initialize removed members.
(san::leave): Don't set removed members.
(class myfault): Only define on 32 bit.
(myfault::faulted): Only keep implementation not taking any parameter.
Drop argument in call to sebastian.setup.
(__try/__leave/__except/__endtry): Implement to support real SEH. For
now stick to SJLJ on 32 bit.
* dcrt0.cc (dll_crt0_0): Drop 64 bit call to
exception::install_myfault_handler.
* exception.h (exception_handler): Define with EXCEPTION_DISPOSITION
as return type.
(PDISPATCHER_CONTEXT): Define as void * on 32 bit. Define as pointer
to _DISPATCHER_CONTEXT on 64 bit.
(class exception): Define separately for 32 and 64 bit.
(exception::myfault): Add handler for myfault SEH handling on 64 bit.
(exception::exception): Fix mangled method name to account for change
in type of last parameter.
(exception::install_myfault_handler): Remove.
* exceptions.cc (exception::myfault_handle): Remove.
(exception::myfault): New SEH handler for 64 bit.
* gendef (_sigbe): Set tls_pathbuf counters to 0 explicitely when
returning to the caller.
* ntdll.h: Move a comment to a better place.
(struct _SCOPE_TABLE): Define on 64 bit.
* thread.cc (verifyable_object_isvalid): Remove gcc 4.7 workaround.
* tls_pbuf.cc (tls_pbuf): Fix to accommodate new place of pathbufs.
(tls_pathbuf::destroy): Change type of loop variables to uint32_t.
* tls_pbuf.h (class tmp_pathbuf): Change type of buffer counters to
uint32_t. Accommodate new place of pathbufs.
* tlsoffsets.h: Regenerate.
* tlsoffsets64.h: Regenerate.
(telldir): Per POSIX, return -1 and set errno to EBADF, rather than
just returning 0, on invalid directory stream.
* signal.cc (sigwaitinfo): Return -1, not EFAULT, when SEGV was catched.
warnings between regparm definitions and declarations.
* smallprint.cc (__small_vswprintf): Conditionalize declaration and
setting of l_opt for only x86_64.
* spawn.cc (child_info_spawn::worker): Remove unused 'pid' variable.
* thread.cc (verifyable_object_isvalid): Temporarily define as
non-inline with gcc 4.7+, regardless of target.
(mainly in fhandler*) start fixing gcc 4.7.2 mismatch between regparm
definitions and declarations.
* gendef: Define some functions to take @ declaration to accommodate _regN
defines which use __stdcall.
* gentls_offsets: Define __regN macros as empty.
* autoload.cc (wsock_init): Remove unneeded regparm attribute.
* winsup.h (__reg1): Define.
(__reg2): Define.
(__reg3): Define.
* advapi32.cc (DuplicateTokenEx): Coerce some initializers to avoid warnings
from gcc 4.7.2.
* exceptions.cc (status_info): Declare struct to use NTSTATUS.
(cygwin_exception::dump_exception): Coerce e->ExceptionCode to NTSTATUS.
* fhandler_clipboard.cc (cygnativeformat): Redefine as UINT to avoid gcc 4.7.2
warnings.
(fhandler_dev_clipboard::read): Ditto.
* sigproc.h (sigdelayed): Make symbol globally available.
* gendef (sigdelayed): Specifically zero incyg and stacklock.
* signal.cc (sigwaitinfo): Lock _my_tls and try harder to clean up signal
information.
* exceptions.cc (sig_handle_tty_stop): Make sure that incyg is cleared when
exiting if we have no parent process. Only wait for signal_arrived.
(sigpacket::process): Make continue_now a bool. Delay sending signal_arrived
until the end. Make code more defensive to avoid calling signal handler when
stopped. Only set signal_arrived when stopped.
* sigproc.cc (sig_hold): Rename from sigCONT. Make static.
(sig_send): Accommodate sigCONT -> sig_hold rename.
(wait_sig): Ditto.
* sigproc.h (sigCONT): Delete declaration.
* fhandler_console.cc (fhandler_console::write): Use new '%0c' facility to
print characters. Change to paranoid to avoid excessive strace output.
* fhandler_tty.cc (fhandler_pty_master::accept_input): Make frequent strace
printf "paranoid" to help cut down on strace output size.
* signal.cc (sigsuspend): Add standard syscall strace output.
(sigpause): Ditto.
(pause): Ditto.
* cygtls.h (_cygtls::reset_signal_arrived): New function.
* cygserver_ipc.h (ipc_set_proc_info): Use _cygtls::ipc_set_proc_info to set
per-thread signal arrived value.
* cygthread.cc (cygthread::detach): Use per-thread signal_arrived via
set_thread_waiting.
* fork.cc (_cygtls::fixup_after_fork): Clear signal_arrived.
(_cygtls::remove): Close any signal_arrived handle when thread exists.
(_cygtls::find_tls): Remove unneeded function.
* cygtls.h: Update copyright.
(class _cygtls): Reorganize to help avoid rebuilding newlib when structure
changes.
(_cygtls::event): Delete.
(_cygtls::threadkill): Ditto.
(_cygtls::signal_waiting): Declare new bool.
(_cygtls::find_tls): Delete declaration.
(_cygtls::set_threadkill): Ditto.
(_cygtls::reset_threadkill): Ditto.
(_cygtls::set_signal_arrived): Declare new function.
(class set_thread_waiting): Declare new class.
* cygwait.cc (cw_nowait_storage): Define.
(cygwait): Set per-thread signal_arrived via set_thread_waiting. Don't
special-case _main_tls.
* cygwait.h (cw_nowait): Define.
(cw_infinite): Ditto.
(cygwait): Redefine pathological wait-only case.
* dcrt0.cc (dll_crt0_0): Remove call to now-defunct events_init().
(dll_crt0_1): Remove call to now-defunct create_signal_arrived().
* exceptions.cc: Reflect set_signal_mask() argument reordering throughout.
Remove signal mask synchronization throughout.
(events_init): Delete definition.
(mask_sync): Delete now-unneeded mask synchronization.
(set_signal_mask): Reverse order of arguments to "standard" to, from layout.
Rename "newmask" argument to "setmask". Remove debugging.
(sig_handle_tty_stop): Use cancelable_wait rather than WFMO.
(_cygtls::interrupt_setup): Don't treat "threadkill" events specially.
Conditionally set signal_arrived depending on whether the thread has created it
or not.
(sigpacket::process): Reorganize to reflect thread-specific sending of signals
which is more in line with the way it was actually supposed to work.
* fhandler_socket.cc (get_inet_addr): Use cancelable_wait rather than
IsEventSignalled to avoid potential race.
(fhandler_socket::wait_for_events): Set signal_arrived event using
set_thread_waiting().
(fhandler_socket::close): Use cygwait for the case of just waiting 10 ms for a
signal.
* fhandler_tape.cc (fhandler_dev_tape::_lock): Use cancelable_wait rather than
WFMO. Redo switch/case tests accordingly.
* fhandler_termios.cc (fhandler_termios::bg_check): Use cygwait for case of
just waiting 0 ms for a potential signal.
* fhandler_tty.cc (fhandler_pty_master::process_slave_output): Use
cancelable_wait rather than WFSO.
* fhandler_windows.cc (fhandler_windows::read): Set per-thread signal_arrived
via set_thread_waiting().
* flock.cc (lf_setlock): Ditto.
* select.cc (pselect): Ditto. Set per-thread signal_arrived using
set_thread_waiting().
* gendef: Don't special case handling of _cygtls::sig for threads.
* gentls_offsets: Use #pragma once in tlsoffsets.h.
* ntdll.h: Use #pragma once.
* poll.cc: Reflect set_signal_mask() argument reordering.
* posix_ipc.cc (ipc_mutex_lock): Use cancelable_wait rather than WFMO.
(ipc_cond_timedwait): Set perl-thread signal arrived using
set_thread_waiting().
* security.h: Use #pragma once.
* signal.cc (abort): Reflect set_signal_mask() argument reordering.
(clock_nanosleep): Ditto. Change call to cancelable_wait to properly specify
handling of cancel and interrupt.
(sigwaitinfo): Remove handling of per-thread event in favor of per-thread
signal_arrived. Use cancelable_wait rather than WFSO.
* sigproc.cc (signal_arrived): Delete definition.
(create_signal_arrived): Ditto.
* sigproc.h (signal_arrived): Delete declaration.
(set_signal_mask): Avoid defining as a "C" function. Don't conditionally
declare.
(create_signal_arrived): Delete declaration.
* syscalls.cc (rename): Use cygwait() rather than WFSO.
* thread.h (fast_mutex::lock): Use cw_infinite rather than LARGE_NULL.
* wait.cc (wait4): Ditto.
* thread.cc (pthread_mutex::lock): Ditto.
(pthread::join): Ditto.
(semaphore::_wait): Ditto.
(pthread_kill): Remove set_threadkill() accommodation.
* tlsoffsets.h: Regenerate.
why -fomit-frame-pointer doesn't work right for passwd.o and path.o. Add
-static to link command line for cygwin0.dll.
* fhandler_disk_file.cc (fhandler_disk_file::facl): Reorganize slightly to
silence compiler warning when compiling with -fstack-check.
* net.cc (inet_ntop6): Initialize structure members to silence compiler warning
when compiling with -fstack-check.
* pseudo-reloc.cc (_pei386_runtime_relocator): Make this a C function. Detect
NULL u.
* winsup.h (_pei386_runtime_relocator): Declare this as extern "C".
* lib/_cygwin_crt0_common.cc (_pei386_runtime_relocator): Call with NULL
argument.
* signal.cc (sigaction_worker): Eliminate last argument. Let callers report
their own strace info. Regparmize.
(sigaction): Reflect sigaction_worker changes.
(siginterrupt): Ditto.
* exceptions.cc: Update copyright.
Corinna Vinschen
Mark Geisert
Ken Brown
Yaakov Selkowitz
Erik Bray
Peter Foley
Christopher Faylor