diff options
Diffstat (limited to 'semaphore.c')
| -rw-r--r-- | semaphore.c | 106 |
1 files changed, 90 insertions, 16 deletions
diff --git a/semaphore.c b/semaphore.c index 9645379..e682201 100644 --- a/semaphore.c +++ b/semaphore.c @@ -34,14 +34,16 @@ * * ------------------------------------------------------------- */ -#include <pthread.h> -#include <string.h> -#include "semaphore.h" +#include <sys/timeb.h> +#include <string.h> + +#include <pthread.h> +#include "implement.h" int -sem_init (sem_t * sem, int pshared, unsigned int value) +_pthread_sem_init (_pthread_sem_t * sem, int pshared, unsigned int value) /* * ------------------------------------------------------ * DOCPUBLIC @@ -50,7 +52,7 @@ sem_init (sem_t * sem, int pshared, unsigned int value) * * PARAMETERS * sem - * pointer to an instance of sem_t + * pointer to an instance of _pthread_sem_t * * pshared * if zero, this semaphore may only be shared between @@ -90,7 +92,7 @@ sem_init (sem_t * sem, int pshared, unsigned int value) { /* * NOTE: Taking advantage of the fact that - * sem_t is a simple structure with one entry; + * _pthread_sem_t is a simple structure with one entry; * We don't have to allocate it... */ *sem = CreateSemaphore ( @@ -111,7 +113,7 @@ sem_init (sem_t * sem, int pshared, unsigned int value) int -sem_destroy (sem_t * sem) +_pthread_sem_destroy (_pthread_sem_t * sem) /* * ------------------------------------------------------ * DOCPUBLIC @@ -119,7 +121,7 @@ sem_destroy (sem_t * sem) * * PARAMETERS * sem - * pointer to an instance of sem_t + * pointer to an instance of _pthread_sem_t * * DESCRIPTION * This function destroys an unnamed semaphore. @@ -144,7 +146,7 @@ sem_destroy (sem_t * sem) int -sem_trywait (sem_t * sem) +_pthread_sem_trywait (_pthread_sem_t * sem) /* * ------------------------------------------------------ * DOCPUBLIC @@ -152,7 +154,7 @@ sem_trywait (sem_t * sem) * * PARAMETERS * sem - * pointer to an instance of sem_t + * pointer to an instance of _pthread_sem_t * * DESCRIPTION * This function tries to wait on a semaphore. If the @@ -181,7 +183,7 @@ sem_trywait (sem_t * sem) int -sem_wait (sem_t * sem) +_pthread_sem_wait (_pthread_sem_t * sem) /* * ------------------------------------------------------ * DOCPUBLIC @@ -189,7 +191,7 @@ sem_wait (sem_t * sem) * * PARAMETERS * sem - * pointer to an instance of sem_t + * pointer to an instance of _pthread_sem_t * * DESCRIPTION * This function waits on a semaphore. If the @@ -219,7 +221,81 @@ sem_wait (sem_t * sem) int -sem_post (sem_t * sem) +_pthread_sem_timedwait (_pthread_sem_t * sem, const struct timespec * abstime) + /* + * ------------------------------------------------------ + * DOCPUBLIC + * This function waits on a semaphore possibly until + * 'abstime' time. + * + * PARAMETERS + * sem + * pointer to an instance of _pthread_sem_t + * + * abstime + * pointer to an instance of struct timespec + * + * DESCRIPTION + * This function waits on a semaphore. If the + * semaphore value is greater than zero, it decreases + * its value by one. If the semaphore value is zero, then + * the calling thread (or process) is blocked until it can + * successfully decrease the value or until interrupted by + * a signal. + * + * If 'abstime' is a NULL pointer then this function will + * block until it can successfully decrease the value or + * until interrupted by a signal. + * + * RESULTS + * 0 successfully decreased semaphore, + * EINVAL 'sem' is not a valid semaphore, + * ENOSYS semaphores are not supported, + * EINTR the function was interrupted by a signal, + * EDEADLK a deadlock condition was detected. + * ETIMEDOUT abstime elapsed before success. + * + * ------------------------------------------------------ + */ +{ +#if defined(__MINGW32__) + struct timeb currSysTime; +#else + struct _timeb currSysTime; +#endif + const DWORD NANOSEC_PER_MILLISEC = 1000000; + const DWORD MILLISEC_PER_SEC = 1000; + DWORD milliseconds; + + if (abstime == NULL) + { + milliseconds = INFINITE; + } + else + { + /* + * Calculate timeout as milliseconds from current system time. + */ + + /* get current system time */ + _ftime(&currSysTime); + + /* subtract current system time from abstime */ + milliseconds = (abstime->tv_sec - currSysTime.time) * MILLISEC_PER_SEC; + milliseconds += (abstime->tv_nsec / NANOSEC_PER_MILLISEC) - + currSysTime.millitm; + } + + return ((sem == NULL) + ? EINVAL + : pthreadCancelableTimedWait (*sem, milliseconds) + ); + +} /* _pthread_sem_timedwait */ + + +int +_pthread_sem_post (_pthread_sem_t * sem) /* * ------------------------------------------------------ * DOCPUBLIC @@ -227,7 +303,7 @@ sem_post (sem_t * sem) * * PARAMETERS * sem - * pointer to an instance of sem_t + * pointer to an instance of _pthread_sem_t * * DESCRIPTION * This function posts a wakeup to a semaphore. If there @@ -249,5 +325,3 @@ sem_post (sem_t * sem) : EINVAL)); } /* sem_post */ - - |