glibc/linuxthreads/signals.c
Ulrich Drepper 3387a425e6 Finish user stack support. Change locking code to be safe in situations with different priorities.
1998-06-25 19:27  Ulrich Drepper  <drepper@cygnus.com>

	* attr.c: Finish user stack support.  Change locking code to be safe
	in situations with different priorities.
	* cancel.c: Likewise.
	* condvar.c: Likewise.
	* internals.h: Likewise.
	* join.c: Likewise.
	* manager.c: Likewise.
	* mutex.c: Likewise.
	* pthread.c: Likewise.
	* ptlongjmp.c: Likewise.
	* queue.h: Likewise.
	* rwlock.c: Likewise.
	* semaphore.c: Likewise.
	* semaphore.h: Likewise.
	* signals.c: Likewise.
	* spinlock.c: Likewise.
	* spinlock.h: Likewise.
	Patches by Xavier leroy.

1998-06-25  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/pthread/pthread.h: Make [sg]et_stacksize and
	[sg]et_stackaddr prototypes always available.

	* sysdeps/unix/sysv/linux/bits/posix_opt.h: Define
	_POSIX_THREAD_ATTR_STACKSIZE and _POSIX_THREAD_ATTR_STACKADDR.
1998-06-25 19:36:00 +00:00

154 lines
4.5 KiB
C

/* Linuxthreads - a simple clone()-based implementation of Posix */
/* threads for Linux. */
/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */
/* */
/* This program is free software; you can redistribute it and/or */
/* modify it under the terms of the GNU Library General Public License */
/* as published by the Free Software Foundation; either version 2 */
/* of the License, or (at your option) any later version. */
/* */
/* This program is distributed in the hope that it will be useful, */
/* but WITHOUT ANY WARRANTY; without even the implied warranty of */
/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the */
/* GNU Library General Public License for more details. */
/* Handling of signals */
#include <errno.h>
#include <signal.h>
#include "pthread.h"
#include "internals.h"
#include "spinlock.h"
int pthread_sigmask(int how, const sigset_t * newmask, sigset_t * oldmask)
{
sigset_t mask;
if (newmask != NULL) {
mask = *newmask;
/* Don't allow PTHREAD_SIG_RESTART to be unmasked.
Don't allow PTHREAD_SIG_CANCEL to be masked. */
switch(how) {
case SIG_SETMASK:
sigaddset(&mask, PTHREAD_SIG_RESTART);
sigdelset(&mask, PTHREAD_SIG_CANCEL);
break;
case SIG_BLOCK:
sigdelset(&mask, PTHREAD_SIG_CANCEL);
break;
case SIG_UNBLOCK:
sigdelset(&mask, PTHREAD_SIG_RESTART);
break;
}
newmask = &mask;
}
if (sigprocmask(how, newmask, oldmask) == -1)
return errno;
else
return 0;
}
int pthread_kill(pthread_t thread, int signo)
{
pthread_handle handle = thread_handle(thread);
int pid;
__pthread_lock(&handle->h_lock);
if (invalid_handle(handle, thread)) {
__pthread_unlock(&handle->h_lock);
return ESRCH;
}
pid = handle->h_descr->p_pid;
__pthread_unlock(&handle->h_lock);
if (kill(pid, signo) == -1)
return errno;
else
return 0;
}
/* User-provided signal handlers */
static __sighandler_t sighandler[NSIG];
/* The wrapper around user-provided signal handlers */
static void pthread_sighandler(int signo)
{
pthread_descr self = thread_self();
char * in_sighandler;
/* If we're in a sigwait operation, just record the signal received
and return without calling the user's handler */
if (self->p_sigwaiting) {
self->p_sigwaiting = 0;
self->p_signal = signo;
return;
}
/* Record that we're in a signal handler and call the user's
handler function */
in_sighandler = self->p_in_sighandler;
if (in_sighandler == NULL) self->p_in_sighandler = CURRENT_STACK_FRAME;
sighandler[signo](signo);
if (in_sighandler == NULL) self->p_in_sighandler = NULL;
}
int sigaction(int sig, const struct sigaction * act,
struct sigaction * oact)
{
struct sigaction newact;
if (sig == PTHREAD_SIG_RESTART || sig == PTHREAD_SIG_CANCEL)
return EINVAL;
newact = *act;
if (act->sa_handler != SIG_IGN && act->sa_handler != SIG_DFL)
newact.sa_handler = pthread_sighandler;
if (__sigaction(sig, &newact, oact) == -1)
return -1;
if (oact != NULL) oact->sa_handler = sighandler[sig];
sighandler[sig] = act->sa_handler;
return 0;
}
int sigwait(const sigset_t * set, int * sig)
{
volatile pthread_descr self = thread_self();
sigset_t mask;
int s;
sigjmp_buf jmpbuf;
/* Get ready to block all signals except those in set
and the cancellation signal */
sigfillset(&mask);
sigdelset(&mask, PTHREAD_SIG_CANCEL);
for (s = 1; s <= NSIG; s++) {
if (sigismember(set, s) && s != PTHREAD_SIG_CANCEL)
sigdelset(&mask, s);
}
/* Test for cancellation */
if (sigsetjmp(jmpbuf, 1) == 0) {
self->p_cancel_jmp = &jmpbuf;
if (! (self->p_canceled && self->p_cancelstate == PTHREAD_CANCEL_ENABLE)) {
/* Reset the signal count */
self->p_signal = 0;
/* Say we're in sigwait */
self->p_sigwaiting = 1;
/* Unblock the signals and wait for them */
sigsuspend(&mask);
}
}
self->p_cancel_jmp = NULL;
/* The signals are now reblocked. Check for cancellation */
pthread_testcancel();
/* We should have self->p_signal != 0 and equal to the signal received */
*sig = self->p_signal;
return 0;
}
int raise (int sig)
{
int retcode = pthread_kill(pthread_self(), sig);
if (retcode == 0)
return 0;
else {
errno = retcode;
return -1;
}
}