/*
* Wrappers around mutex/cond/thread functions
*
* Copyright Red Hat, Inc. 2009
*
* Author:
* Marcelo Tosatti <mtosatti@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <time.h>
#include <signal.h>
#include <stdint.h>
#include <string.h>
#include <limits.h>
#include <unistd.h>
#include <sys/time.h>
#include "qemu-thread.h"
static void error_exit(int err, const char *msg)
{
fprintf(stderr, "qemu: %s: %s\n", msg, strerror(err));
abort();
}
void qemu_mutex_init(QemuMutex *mutex)
{
int err;
pthread_mutexattr_t mutexattr;
pthread_mutexattr_init(&mutexattr);
pthread_mutexattr_settype(&mutexattr, PTHREAD_MUTEX_ERRORCHECK);
err = pthread_mutex_init(&mutex->lock, &mutexattr);
pthread_mutexattr_destroy(&mutexattr);
if (err)
error_exit(err, __func__);
}
void qemu_mutex_destroy(QemuMutex *mutex)
{
int err;
err = pthread_mutex_destroy(&mutex->lock);
if (err)
error_exit(err, __func__);
}
void qemu_mutex_lock(QemuMutex *mutex)
{
int err;
err = pthread_mutex_lock(&mutex->lock);
if (err)
error_exit(err, __func__);
}
int qemu_mutex_trylock(QemuMutex *mutex)
{
return pthread_mutex_trylock(&mutex->lock);
}
void qemu_mutex_unlock(QemuMutex *mutex)
{
int err;
err = pthread_mutex_unlock(&mutex->lock);
if (err)
error_exit(err, __func__);
}
void qemu_cond_init(QemuCond *cond)
{
int err;
err = pthread_cond_init(&cond->cond, NULL);
if (err)
error_exit(err, __func__);
}
void qemu_cond_destroy(QemuCond *cond)
{
int err;
err = pthread_cond_destroy(&cond->cond);
if (err)
error_exit(err, __func__);
}
void qemu_cond_signal(QemuCond *cond)
{
int err;
err = pthread_cond_signal(&cond->cond);
if (err)
error_exit(err, __func__);
}
void qemu_cond_broadcast(QemuCond *cond)
{
int err;
err = pthread_cond_broadcast(&cond->cond);
if (err)
error_exit(err, __func__);
}
void qemu_cond_wait(QemuCond *cond, QemuMutex *mutex)
{
int err;
err = pthread_cond_wait(&cond->cond, &mutex->lock);
if (err)
error_exit(err, __func__);
}
void qemu_sem_init(QemuSemaphore *sem, int init)
{
int rc;
#if defined(__OpenBSD__) || defined(__APPLE__) || defined(__NetBSD__)
rc = pthread_mutex_init(&sem->lock, NULL);
if (rc != 0) {
error_exit(rc, __func__);
}
rc = pthread_cond_init(&sem->cond, NULL);
if (rc != 0) {
error_exit(rc, __func__);
}
if (init < 0) {
error_exit(EINVAL, __func__);
}
sem->count = init;
#else
rc = sem_init(&sem->sem, 0, init);
if (rc < 0) {
error_exit(errno, __func__);
}
#endif
}
void qemu_sem_destroy(QemuSemaphore *sem)
{
int rc;
#if defined(__OpenBSD__) || defined(__APPLE__) || defined(__NetBSD__)
rc = pthread_cond_destroy(&sem->cond);
if (rc < 0) {
error_exit(rc, __func__);
}
rc = pthread_mutex_destroy(&sem->lock);
if (rc < 0) {
error_exit(rc, __func__);
}
#else
rc = sem_destroy(&sem->sem);
if (rc < 0) {
error_exit(errno, __func__);
}
#endif
}
void qemu_sem_post(QemuSemaphore *sem)
{
int rc;
#if defined(__OpenBSD__) || defined(__APPLE__) || defined(__NetBSD__)
pthread_mutex_lock(&sem->lock);
if (sem->count == INT_MAX) {
rc = EINVAL;
} else if (sem->count++ < 0) {
rc = pthread_cond_signal(&sem->cond);
} else {
rc = 0;
}
pthread_mutex_unlock(&sem->lock);
if (rc != 0) {
error_exit(rc, __func__);
}
#else
rc = sem_post(&sem->sem);
if (rc < 0) {
error_exit(errno, __func__);
}
#endif
}
static void compute_abs_deadline(struct timespec *ts, int ms)
{
struct timeval tv;
gettimeofday(&tv, NULL);
ts->tv_nsec = tv.tv_usec * 1000 + (ms % 1000) * 1000000;
ts->tv_sec = tv.tv_sec + ms / 1000;
if (ts->tv_nsec >= 1000000000) {
ts->tv_sec++;
ts->tv_nsec -= 1000000000;
}
}
int qemu_sem_timedwait(QemuSemaphore *sem, int ms)
{
int rc;
struct timespec ts;
#if defined(__OpenBSD__) || defined(__APPLE__) || defined(__NetBSD__)
compute_abs_deadline(&ts, ms);
pthread_mutex_lock(&sem->lock);
--sem->count;
while (sem->count < 0) {
rc = pthread_cond_timedwait(&sem->cond, &sem->lock, &ts);
if (rc == ETIMEDOUT) {
break;
}
if (rc != 0) {
error_exit(rc, __func__);
}
}
pthread_mutex_unlock(&sem->lock);
return (rc == ETIMEDOUT ? -1 : 0);
#else
if (ms <= 0) {
/* This is cheaper than sem_timedwait. */
do {
rc = sem_trywait(&sem->sem);
} while (rc == -1 && errno == EINTR);
if (rc == -1 && errno == EAGAIN) {
return -1;
}
} else {
compute_abs_deadline(&ts, ms);
do {
rc = sem_timedwait(&sem->sem, &ts);
} while (rc == -1 && errno == EINTR);
if (rc == -1 && errno == ETIMEDOUT) {
return -1;
}
}
if (rc < 0) {
error_exit(errno, __func__);
}
return 0;
#endif
}
void qemu_sem_wait(QemuSemaphore *sem)
{
#if defined(__OpenBSD__) || defined(__APPLE__) || defined(__NetBSD__)
pthread_mutex_lock(&sem->lock);
--sem->count;
while (sem->count < 0) {
pthread_cond_wait(&sem->cond, &sem->lock);
}
pthread_mutex_unlock(&sem->lock);
#else
int rc;
do {
rc = sem_wait(&sem->sem);
} while (rc == -1 && errno == EINTR);
if (rc < 0) {
error_exit(errno, __func__);
}
#endif
}
void qemu_thread_create(QemuThread *thread,
void *(*start_routine)(void*),
void *arg, int mode)
{
sigset_t set, oldset;
int err;
pthread_attr_t attr;
err = pthread_attr_init(&attr);
if (err) {
error_exit(err, __func__);
}
if (mode == QEMU_THREAD_DETACHED) {
err = pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
if (err) {
error_exit(err, __func__);
}
}
/* Leave signal handling to the iothread. */
sigfillset(&set);
pthread_sigmask(SIG_SETMASK, &set, &oldset);
err = pthread_create(&thread->thread, &attr, start_routine, arg);
if (err)
error_exit(err, __func__);
pthread_sigmask(SIG_SETMASK, &oldset, NULL);
pthread_attr_destroy(&attr);
}
void qemu_thread_get_self(QemuThread *thread)
{
thread->thread = pthread_self();
}
bool qemu_thread_is_self(QemuThread *thread)
{
return pthread_equal(pthread_self(), thread->thread);
}
void qemu_thread_exit(void *retval)
{
pthread_exit(retval);
}
void *qemu_thread_join(QemuThread *thread)
{
int err;
void *ret;
err = pthread_join(thread->thread, &ret);
if (err) {
error_exit(err, __func__);
}
return ret;
}
