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/*******************************************************************************
* Copyright (C) ST-Ericsson SA 2011
* License terms: 3-clause BSD license
******************************************************************************/
#include <errno.h>
#include <sys/time.h>
#include <fcntl.h>
#include <time.h>
#include "Types.h"
#include "CEventObject.h"
#include "OS.h"
// ******************************************************************************
// Name: CEventObject()
// Desc: CEventObject constructor which initializes the m_sem member
// Ret:
// ******************************************************************************
CEventObject::CEventObject()
{
char sem_name[SEM_NAME_MAX_LENGTH];
int sem_nr = 1;
while(sem_nr <= SEM_MAX_NR) {
snprintf(sem_name, SEM_NAME_MAX_LENGTH, "lcdriversem_%d", sem_nr);
/* open semaphore with "rw" permissions for everyone - 0666 */
m_sem = sem_open(sem_name, O_CREAT | O_EXCL, 0666 , 0);
if (m_sem != SEM_FAILED)
break;
sem_nr++;
}
}
// ******************************************************************************
// Name: ~CEventObject()
// Desc: CEventObject destructor
// Ret:
// ******************************************************************************
CEventObject::~CEventObject()
{
sem_close(m_sem);
}
// ******************************************************************************
// Name: SetEvent()
// Desc: Sets an event by post-ing the member semaphore m_sem
// Ret:
// ******************************************************************************
void CEventObject::SetEvent()
{
sem_post(m_sem);
}
// ******************************************************************************
// Name: Wait()
// Desc: implementation of the pure virtual base class member Wait()
// Ret: WAIT_OBJECT_0 when event occurs, or WAIT_TIMEOUT on timeout
// ******************************************************************************
DWORD CEventObject::Wait(DWORD dwTimeout)
{
if (INFINITE == dwTimeout) {
sem_wait(m_sem);
} else {
struct timeval curr_time, start_time;
DWORD dwTimePassed = 0;
int ret;
gettimeofday(&start_time, NULL);
/* Try to lock the semaphore */
ret = sem_trywait(m_sem);
if (ret != 0) {
while (dwTimePassed < dwTimeout) {
/* Sleep 1ms */
OS::Sleep(1);
/* Try to lock the semaphore again*/
ret = sem_trywait(m_sem);
if (ret == 0) {
return WAIT_OBJECT_0;
}
gettimeofday(&curr_time, NULL);
dwTimePassed = 1000 * (curr_time.tv_sec - start_time.tv_sec) + \
(curr_time.tv_usec - start_time.tv_usec) / 1000;
}
return WAIT_TIMEOUT;
}
}
return WAIT_OBJECT_0;
}
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