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/* 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, NULL);
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 (THREAD_GETMEM(self, p_sigwaiting)) {
THREAD_SETMEM(self, p_sigwaiting, 0);
THREAD_SETMEM(self, p_signal, signo);
return;
}
/* Record that we're in a signal handler and call the user's
handler function */
in_sighandler = THREAD_GETMEM(self, p_in_sighandler);
if (in_sighandler == NULL)
THREAD_SETMEM(self, p_in_sighandler, CURRENT_STACK_FRAME);
sighandler[signo](signo);
if (in_sighandler == NULL)
THREAD_SETMEM(self, p_in_sighandler, NULL);
}
int sigaction(int sig, const struct sigaction * act,
struct sigaction * oact)
{
struct sigaction newact;
struct sigaction *newactp;
if (sig == __pthread_sig_restart || sig == __pthread_sig_cancel)
return EINVAL;
if (act)
{
newact = *act;
if (act->sa_handler != SIG_IGN && act->sa_handler != SIG_DFL
&& sig < NSIG)
newact.sa_handler = pthread_sighandler;
newactp = &newact;
}
else
newactp = NULL;
if (__sigaction(sig, newactp, oact) == -1)
return -1;
if (sig < NSIG)
{
if (oact != NULL)
oact->sa_handler = sighandler[sig];
if (act)
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) {
THREAD_SETMEM(self, p_cancel_jmp, &jmpbuf);
if (! (THREAD_GETMEM(self, p_canceled)
&& THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE)) {
/* Reset the signal count */
THREAD_SETMEM(self, p_signal, 0);
/* Say we're in sigwait */
THREAD_SETMEM(self, p_sigwaiting, 1);
/* Unblock the signals and wait for them */
sigsuspend(&mask);
}
}
THREAD_SETMEM(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 = THREAD_GETMEM(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;
}
}
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