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/*
* Copyright (c) 2003 Jeffrey Roberson <jeff@freebsd.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice unmodified, this list of conditions, and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <sys/cdefs.h>
#include <sys/types.h>
#include <sys/signalvar.h>
#include <sys/time.h>
#include <sys/timespec.h>
#include <pthread.h>
#include <signal.h>
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include "thr_private.h"
/* XXX Why can't I get this from time.h? :-( */
#define timespecsub(vvp, uvp) \
do { \
(vvp)->tv_sec -= (uvp)->tv_sec; \
(vvp)->tv_nsec -= (uvp)->tv_nsec; \
if ((vvp)->tv_nsec < 0) { \
(vvp)->tv_sec--; \
(vvp)->tv_nsec += 1000000000; \
} \
} while (0)
static sigset_t restore;
void
_thread_critical_enter(pthread_t pthread)
{
_thread_sigblock();
UMTX_LOCK(&pthread->lock);
}
void
_thread_critical_exit(pthread_t pthread)
{
UMTX_UNLOCK(&pthread->lock);
_thread_sigunblock();
}
void
_thread_sigblock()
{
sigset_t set;
sigset_t sav;
/*
* Block all signals.
*/
SIGFILLSET(set);
SIGADDSET(set, SIGTHR);
/* If we have already blocked signals, just up the refcount */
if (++curthread->signest > 1)
return;
PTHREAD_ASSERT(curthread->signest == 1,
("Blocked signal nesting level must be 1!"));
if (__sys_sigprocmask(SIG_SETMASK, &set, &sav)) {
_thread_printf(STDERR_FILENO, "Critical Enter: sig err %d\n",
errno);
abort();
}
curthread->savedsig = sav;
}
void
_thread_sigunblock()
{
sigset_t set;
/* We might be in a nested 'blocked signal' section */
if (--curthread->signest > 0)
return;
PTHREAD_ASSERT(curthread->signest == 0,
("Non-Zero blocked signal nesting level."));
/*
* Restore signals.
*/
set = curthread->savedsig;
if (__sys_sigprocmask(SIG_SETMASK, &set, NULL)) {
_thread_printf(STDERR_FILENO, "Critical Exit: sig err %d\n",
errno);
abort();
}
}
void
GIANT_LOCK(pthread_t pthread)
{
sigset_t set;
sigset_t sav;
int error;
/*
* Block all signals.
*/
SIGFILLSET(set);
/*
* We can not use the global 'restore' set until after we have
* acquired the giant lock.
*/
#if 0
error = __sys_sigprocmask(SIG_SETMASK, &set, &sav);
if (error) {
_thread_printf(STDERR_FILENO, "GIANT_LOCK: sig err %d\n",
errno);
abort();
}
#endif
error = umtx_lock(&_giant_mutex, pthread->thr_id);
if (error) {
_thread_printf(STDERR_FILENO, "GIANT_LOCK: %d\n", errno);
abort();
}
restore = sav;
}
void
GIANT_UNLOCK(pthread_t pthread)
{
sigset_t set;
int error;
/*
* restore is protected by giant. We could restore our signal state
* incorrectly if someone else set restore between unlocking giant
* and restoring the signal mask. To avoid this we cache a copy prior
* to the unlock.
*/
set = restore;
error = umtx_unlock(&_giant_mutex, pthread->thr_id);
if (error) {
_thread_printf(STDERR_FILENO, "GIANT_UNLOCK: %d\n", errno);
abort();
}
#if 0
/*
* Restore signals.
*/
error = __sys_sigprocmask(SIG_SETMASK, &set, NULL);
if (error) {
_thread_printf(STDERR_FILENO, "GIANT_UNLOCK: sig err %d\n",
errno);
abort();
}
#endif
}
int
_thread_suspend(pthread_t pthread, struct timespec *abstime)
{
struct timespec remaining;
struct timespec *ts;
siginfo_t info;
int error;
/*
* Compute the remainder of the run time.
*/
if (abstime) {
struct timespec now;
struct timeval tv;
GET_CURRENT_TOD(tv);
TIMEVAL_TO_TIMESPEC(&tv, &now);
remaining = *abstime;
timespecsub(&remaining, &now);
ts = &remaining;
} else
ts = NULL;
error = sigtimedwait(&_thread_suspend_sigset, &info, ts);
error = (error == -1) ? errno : 0;
return (error);
}
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