108 lines
3.1 KiB
C++
108 lines
3.1 KiB
C++
/*
|
|
* Copyright (C) 2009-2015 Max Kellermann <max.kellermann@gmail.com>
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
*
|
|
* - Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
*
|
|
* - 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 COPYRIGHT HOLDERS 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
|
|
* FOUNDATION 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.
|
|
*/
|
|
|
|
#ifndef THREAD_POSIX_COND_HXX
|
|
#define THREAD_POSIX_COND_HXX
|
|
|
|
#include "PosixMutex.hxx"
|
|
|
|
#include <chrono>
|
|
|
|
#include <sys/time.h>
|
|
|
|
/**
|
|
* Low-level wrapper for a pthread_cond_t.
|
|
*/
|
|
class PosixCond {
|
|
pthread_cond_t cond;
|
|
|
|
public:
|
|
#ifdef __GLIBC__
|
|
/* optimized constexpr constructor for pthread implementations
|
|
that support it */
|
|
constexpr PosixCond():cond(PTHREAD_COND_INITIALIZER) {}
|
|
#else
|
|
/* slow fallback for pthread implementations that are not
|
|
compatible with "constexpr" */
|
|
PosixCond() {
|
|
pthread_cond_init(&cond, nullptr);
|
|
}
|
|
|
|
~PosixCond() {
|
|
pthread_cond_destroy(&cond);
|
|
}
|
|
#endif
|
|
|
|
PosixCond(const PosixCond &other) = delete;
|
|
PosixCond &operator=(const PosixCond &other) = delete;
|
|
|
|
void signal() {
|
|
pthread_cond_signal(&cond);
|
|
}
|
|
|
|
void broadcast() {
|
|
pthread_cond_broadcast(&cond);
|
|
}
|
|
|
|
void wait(PosixMutex &mutex) {
|
|
pthread_cond_wait(&cond, &mutex.mutex);
|
|
}
|
|
|
|
private:
|
|
bool timed_wait(PosixMutex &mutex, unsigned timeout_ms) {
|
|
struct timeval now;
|
|
gettimeofday(&now, nullptr);
|
|
|
|
struct timespec ts;
|
|
ts.tv_sec = now.tv_sec + timeout_ms / 1000;
|
|
ts.tv_nsec = (now.tv_usec + (timeout_ms % 1000) * 1000) * 1000;
|
|
// Keep tv_nsec < 1E9 to prevent return of EINVAL
|
|
if (ts.tv_nsec >= 1000000000) {
|
|
ts.tv_nsec -= 1000000000;
|
|
ts.tv_sec++;
|
|
}
|
|
|
|
return pthread_cond_timedwait(&cond, &mutex.mutex, &ts) == 0;
|
|
}
|
|
|
|
public:
|
|
bool timed_wait(PosixMutex &mutex,
|
|
std::chrono::steady_clock::duration timeout) {
|
|
auto timeout_ms = std::chrono::duration_cast<std::chrono::milliseconds>(timeout).count();
|
|
if (timeout_ms < 0)
|
|
timeout_ms = 0;
|
|
else if (timeout_ms > std::numeric_limits<unsigned>::max())
|
|
timeout_ms = std::numeric_limits<unsigned>::max();
|
|
|
|
return timed_wait(mutex, timeout_ms);
|
|
}
|
|
};
|
|
|
|
#endif
|