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#include "semaphore.h"
#include <hugin.hpp>
#include <limits>
#include <assert.h>
#include <string.h>
#include <chrono>
#include <thread>
#include "platform.h"
#if DG_PLATFORM != DG_PLATFORM_WINDOWS
#include <../include/semaphore.h>
#include <errno.h>
#include <stdio.h>
#include <sys/time.h>
#endif
#if DG_PLATFORM == DG_PLATFORM_OSX
#include <CoreServices/CoreServices.h>
#endif
struct semaphore_private_t {
#if DG_PLATFORM == DG_PLATFORM_WINDOWS
HANDLE semaphore;
#elif DG_PLATFORM == DG_PLATFORM_OSX
MPSemaphoreID semaphore;
#else
sem_t semaphore;
#endif
};
Semaphore::Semaphore(std::size_t initial_count)
{
prv = new struct semaphore_private_t();
#if DG_PLATFORM == DG_PLATFORM_WINDOWS
prv->semaphore = CreateSemaphore(nullptr,
initial_count,
std::numeric_limits<LONG>::max(),
nullptr);
#elif DG_PLATFORM == DG_PLATFORM_OSX
MPCreateSemaphore(std::numeric_limits<std::uint32_t>::max(),
initial_count,
&prv->semaphore);
#else
const int pshared = 0;
memset(&prv->semaphore, 0, sizeof(sem_t));
sem_init(&prv->semaphore, pshared, initial_count);
#endif
}
Semaphore::~Semaphore()
{
#if DG_PLATFORM == DG_PLATFORM_WINDOWS
CloseHandle(prv->semaphore);
#elif DG_PLATFORM == DG_PLATFORM_OSX
MPDeleteSemaphore(prv->semaphore);
#else
sem_destroy(&prv->semaphore);
#endif
delete prv;
}
void Semaphore::post()
{
#if DG_PLATFORM == DG_PLATFORM_WINDOWS
ReleaseSemaphore(prv->semaphore, 1, nullptr);
#elif DG_PLATFORM == DG_PLATFORM_OSX
MPSignalSemaphore(prv->semaphore);
#else
sem_post(&prv->semaphore);
#endif
}
bool Semaphore::wait(const std::chrono::milliseconds& timeout)
{
#if DG_PLATFORM == DG_PLATFORM_WINDOWS
DWORD ret = WaitForSingleObject(prv->semaphore, timeout.count());
if(ret == WAIT_TIMEOUT)
{
return false;
}
assert(ret == WAIT_OBJECT_0);
#elif DG_PLATFORM == DG_PLATFORM_OSX
auto ret = MPWaitOnSemaphore(prv->semaphore,
kDurationMillisecond * timeout.count());
if(ret == kMPTimeoutErr)
{
return false;
}
#else
struct timespec ts;
clock_gettime(CLOCK_REALTIME, &ts);
time_t seconds = (time_t)(timeout.count() / 1000);
ts.tv_sec += seconds;
ts.tv_nsec += (long)((timeout.count() % 1000) * 1000000);
constexpr long nsec = 1000000000LL;
if(ts.tv_nsec >= nsec)
{
ts.tv_nsec -= nsec;
ts.tv_sec += 1;
}
again:
int ret = sem_timedwait(&prv->semaphore, &ts);
if(ret < 0)
{
if(errno == EINTR)
{
std::this_thread::sleep_for(std::chrono::milliseconds(1));
goto again;
}
if(errno == ETIMEDOUT)
{
return false;
}
perror("sem_timedwait()");
assert(false);
}
#endif
return true;
}
void Semaphore::wait()
{
#if DG_PLATFORM == DG_PLATFORM_WINDOWS
WaitForSingleObject(prv->semaphore, INFINITE);
#elif DG_PLATFORM == DG_PLATFORM_OSX
MPWaitOnSemaphore(prv->semaphore, kDurationForever);
#else
again:
int ret = sem_wait(&prv->semaphore);
if(ret < 0)
{
if(errno == EINTR)
{
std::this_thread::sleep_for(std::chrono::milliseconds(1));
goto again;
}
perror("sem_wait()");
assert(false);
}
#endif
}
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