freebsd-dev/lib/librt/mq.c
David Xu f4213b9006 To support stack unwinding for cancellation points, add -fexceptions flag
for them, two functions _pthread_cancel_enter and _pthread_cancel_leave
are added to let thread enter and leave a cancellation point, it also
makes it possible that other functions can be cancellation points in
libraries without having to be rewritten in libthr.
2010-09-25 01:57:47 +00:00

281 lines
6.9 KiB
C

/*-
* Copyright (c) 2006 David Xu <davidxu@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, 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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/syscall.h>
#include <sys/mqueue.h>
#include "namespace.h"
#include <errno.h>
#include <pthread.h>
#include <stddef.h>
#include <stdlib.h>
#include <signal.h>
#include "sigev_thread.h"
#include "un-namespace.h"
#include "libc_private.h"
extern int __sys_kmq_notify(int, const struct sigevent *);
extern int __sys_kmq_open(const char *, int, mode_t,
const struct mq_attr *);
extern int __sys_kmq_setattr(int, const struct mq_attr *__restrict,
struct mq_attr *__restrict);
extern ssize_t __sys_kmq_timedreceive(int, char *__restrict, size_t,
unsigned *__restrict, const struct timespec *__restrict);
extern int __sys_kmq_timedsend(int, const char *, size_t, unsigned,
const struct timespec *);
extern int __sys_kmq_unlink(const char *);
extern int __sys_close(int fd);
struct __mq {
int oshandle;
struct sigev_node *node;
};
__weak_reference(__mq_open, mq_open);
__weak_reference(__mq_open, _mq_open);
__weak_reference(__mq_close, mq_close);
__weak_reference(__mq_close, _mq_close);
__weak_reference(__mq_notify, mq_notify);
__weak_reference(__mq_notify, _mq_notify);
__weak_reference(__mq_getattr, mq_getattr);
__weak_reference(__mq_getattr, _mq_getattr);
__weak_reference(__mq_setattr, mq_setattr);
__weak_reference(__mq_setattr, _mq_setattr);
__weak_reference(__mq_timedreceive_cancel, mq_timedreceive);
__weak_reference(__mq_timedreceive, _mq_timedreceive);
__weak_reference(__mq_timedsend_cancel, mq_timedsend);
__weak_reference(__mq_timedsend, _mq_timedsend);
__weak_reference(__mq_unlink, mq_unlink);
__weak_reference(__mq_unlink, _mq_unlink);
__weak_reference(__mq_send_cancel, mq_send);
__weak_reference(__mq_send, _mq_send);
__weak_reference(__mq_receive_cancel, mq_receive);
__weak_reference(__mq_receive, _mq_receive);
mqd_t
__mq_open(const char *name, int oflag, mode_t mode,
const struct mq_attr *attr)
{
struct __mq *mq;
int err;
mq = malloc(sizeof(struct __mq));
if (mq == NULL)
return (NULL);
mq->oshandle = __sys_kmq_open(name, oflag, mode, attr);
if (mq->oshandle != -1) {
mq->node = NULL;
return (mq);
}
err = errno;
free(mq);
errno = err;
return ((mqd_t)-1L);
}
int
__mq_close(mqd_t mqd)
{
int h;
if (mqd->node != NULL) {
__sigev_list_lock();
__sigev_delete_node(mqd->node);
__sigev_list_unlock();
}
h = mqd->oshandle;
free(mqd);
return (__sys_close(h));
}
typedef void (*mq_func)(union sigval val);
static void
mq_dispatch(struct sigev_node *sn)
{
mq_func f = sn->sn_func;
/*
* Check generation before calling user function,
* this should avoid expired notification.
*/
if (sn->sn_gen == sn->sn_info.si_value.sival_int)
f(sn->sn_value);
}
int
__mq_notify(mqd_t mqd, const struct sigevent *evp)
{
struct sigevent ev;
struct sigev_node *sn;
int ret;
if (evp == NULL || evp->sigev_notify != SIGEV_THREAD) {
if (mqd->node != NULL) {
__sigev_list_lock();
__sigev_delete_node(mqd->node);
mqd->node = NULL;
__sigev_list_unlock();
}
return __sys_kmq_notify(mqd->oshandle, evp);
}
if (__sigev_check_init()) {
/*
* Thread library is not enabled.
*/
errno = EINVAL;
return (-1);
}
sn = __sigev_alloc(SI_MESGQ, evp, mqd->node, 1);
if (sn == NULL) {
errno = EAGAIN;
return (-1);
}
sn->sn_id = mqd->oshandle;
sn->sn_dispatch = mq_dispatch;
__sigev_get_sigevent(sn, &ev, sn->sn_gen);
__sigev_list_lock();
if (mqd->node != NULL)
__sigev_delete_node(mqd->node);
mqd->node = sn;
__sigev_register(sn);
ret = __sys_kmq_notify(mqd->oshandle, &ev);
__sigev_list_unlock();
return (ret);
}
int
__mq_getattr(mqd_t mqd, struct mq_attr *attr)
{
return __sys_kmq_setattr(mqd->oshandle, NULL, attr);
}
int
__mq_setattr(mqd_t mqd, const struct mq_attr *newattr, struct mq_attr *oldattr)
{
return __sys_kmq_setattr(mqd->oshandle, newattr, oldattr);
}
ssize_t
__mq_timedreceive(mqd_t mqd, char *buf, size_t len,
unsigned *prio, const struct timespec *timeout)
{
return __sys_kmq_timedreceive(mqd->oshandle, buf, len, prio, timeout);
}
ssize_t
__mq_timedreceive_cancel(mqd_t mqd, char *buf, size_t len,
unsigned *prio, const struct timespec *timeout)
{
int ret;
_pthread_cancel_enter(1);
ret = __sys_kmq_timedreceive(mqd->oshandle, buf, len, prio, timeout);
_pthread_cancel_leave(ret == -1);
return (ret);
}
ssize_t
__mq_receive(mqd_t mqd, char *buf, size_t len, unsigned *prio)
{
return __sys_kmq_timedreceive(mqd->oshandle, buf, len, prio, NULL);
}
ssize_t
__mq_receive_cancel(mqd_t mqd, char *buf, size_t len, unsigned *prio)
{
int ret;
_pthread_cancel_enter(1);
ret = __sys_kmq_timedreceive(mqd->oshandle, buf, len, prio, NULL);
_pthread_cancel_leave(ret == -1);
return (ret);
}
ssize_t
__mq_timedsend(mqd_t mqd, char *buf, size_t len,
unsigned prio, const struct timespec *timeout)
{
return __sys_kmq_timedsend(mqd->oshandle, buf, len, prio, timeout);
}
ssize_t
__mq_timedsend_cancel(mqd_t mqd, char *buf, size_t len,
unsigned prio, const struct timespec *timeout)
{
int ret;
_pthread_cancel_enter(1);
ret = __sys_kmq_timedsend(mqd->oshandle, buf, len, prio, timeout);
_pthread_cancel_leave(ret == -1);
return (ret);
}
ssize_t
__mq_send(mqd_t mqd, char *buf, size_t len, unsigned prio)
{
return __sys_kmq_timedsend(mqd->oshandle, buf, len, prio, NULL);
}
ssize_t
__mq_send_cancel(mqd_t mqd, char *buf, size_t len, unsigned prio)
{
int ret;
_pthread_cancel_enter(1);
ret = __sys_kmq_timedsend(mqd->oshandle, buf, len, prio, NULL);
_pthread_cancel_leave(ret == -1);
return (ret);
}
int
__mq_unlink(const char *path)
{
return __sys_kmq_unlink(path);
}
int
__mq_oshandle(mqd_t mqd)
{
return (mqd->oshandle);
}