/* This program is free software; you can redistribute it and/or modify it
* under the terms of the license (GNU LGPL) which comes with this package. */
+#ifdef HAVE_PTHREAD_H
+/* XOPEN_SOURCE is needed to get sem_timedwait (on amd64 at least). Declare it before everything else to play safe. */
+#define _XOPEN_SOURCE 600
+#endif
+
#include "xbt/sysdep.h"
#include "xbt/ex.h"
#include "xbt/ex_interface.h" /* We play crude games with exceptions */
/* ********************************* PTHREAD IMPLEMENTATION ************************************ */
#ifdef HAVE_PTHREAD_H
+
+/* XOPEN_SOURCE is needed to get sem_timedwait (on amd64 at least) according to the man page,
+ but the headers seem to follow __USE_XOPEN2K.
+ So let's get safe and declare both before loading headers. */
+#define _XOPEN_SOURCE 600
+#include <features.h>
+
#include <pthread.h>
#include <semaphore.h>
-/* use named sempahore instead */
-#ifndef HAVE_SEM_WAIT
-# define MAX_SEM_NAME ((size_t)13)
- static int __next_sem_ID = 0;
- static pthread_mutex_t __next_sem_ID_lock;
+
+/* use named sempahore when sem_init() does not work */
+#ifndef HAVE_SEM_INIT
+ static int next_sem_ID = 0;
+ static xbt_os_mutex_t next_sem_ID_lock;
#endif
typedef struct xbt_os_thread_ {
__xbt_ex_ctx = _os_thread_ex_ctx;
__xbt_ex_terminate = _os_thread_ex_terminate;
+ thread_mod_inited = 1;
+
#ifndef HAVE_SEM_WAIT
-
- /* initialize the mutex use to protect the incrementation of the variable __next_sem_ID
- * used to build the name of the named sempahore
- */
- if ((errcode = pthread_mutex_init(&__next_sem_ID_lock,NULL)))
- THROW1(system_error,errcode,"pthread_mutex_init() failed: %s",strerror(errcode));
-
+ next_sem_ID_lock = xbt_os_mutex_init();
#endif
- thread_mod_inited = 1;
}
void xbt_os_thread_mod_exit(void) {
/* FIXME: don't try to free our key on shutdown.
}
-
-#ifndef HAVE_PTHREAD_MUTEX_TIMEDLOCK
-/* if the function is not availabled or if is MAC OS X use pthread_mutex_trylock() to define
- * it.
- */
-#include <time.h> /* declaration of the timespec structure and of the nanosleep() function */
-int pthread_mutex_timedlock(pthread_mutex_t * mutex, const struct timespec * abs_timeout)
-{
- int rv;
- long ellapsed_time = 0;
- struct timespec ts;
-
- do
- {
- /* the mutex could not be acquired because it was already locked by an other thread */
- rv = pthread_mutex_trylock(mutex);
-
- ts.tv_sec = 0;
- ts.tv_nsec = 2.5e7 /* (25 ms (2 context switch + 5 ms)) */;
-
- do
- {
- nanosleep(&ts, &ts);
- }while(EINTR == errno);
-
- ellapsed_time += ts.tv_nsec;
-
- }
- while (/* locked */ (EBUSY == rv) && /* !timeout */ (ellapsed_time < ((long)(abs_timeout->tv_sec * 1e9) + abs_timeout->tv_nsec)));
-
- return (EBUSY == rv) ? ETIMEDOUT : rv;
-}
-
-#endif
-
void xbt_os_mutex_timedacquire(xbt_os_mutex_t mutex, double delay) {
int errcode;
- struct timespec ts_end;
- double end = delay + xbt_os_time();
if (delay < 0) {
xbt_os_mutex_acquire(mutex);
- }
- else if(!delay /* equals 0 */)
- {
- if ((errcode=pthread_mutex_trylock(&(mutex->m))))
- THROW2(system_error,errcode,"pthread_mutex_trylock(%p) failed: %s",mutex, strerror(errcode));
+
+ } else if (delay == 0) {
+ errcode=pthread_mutex_trylock(&(mutex->m));
+
+ switch (errcode) {
+ case 0:
+ return;
+ case ETIMEDOUT:
+ THROW1(timeout_error,0,"mutex %p not ready",mutex);
+ default:
+ THROW2(system_error,errcode,"xbt_mutex_tryacquire(%p) failed: %s",mutex, strerror(errcode));
+ }
+
} else {
+
+#ifdef HAVE_MUTEX_TIMEDLOCK
+ struct timespec ts_end;
+ double end = delay + xbt_os_time();
+
ts_end.tv_sec = (time_t) floor(end);
ts_end.tv_nsec = (long) ( ( end - ts_end.tv_sec) * 1000000000);
DEBUG2("pthread_mutex_timedlock(%p,%p)",&(mutex->m), &ts_end);
- switch ((errcode=pthread_mutex_timedlock(&(mutex->m),&ts_end)))
- {
- case 0:
- return;
-
- case ETIMEDOUT:
- THROW2(timeout_error,errcode,"mutex %p wasn't signaled before timeout (%f)",mutex,delay);
-
- default:
- THROW3(system_error,errcode,"pthread_mutex_timedlock(%p,%f) failed: %s",mutex,delay, strerror(errcode));
- }
- }
+ errcode=pthread_mutex_timedlock(&(mutex->m),&ts_end);
+
+#else /* Well, let's reimplement it since those lazy libc dudes didn't */
+ double start = xbt_os_time();
+ do {
+ errcode = pthread_mutex_trylock(&(mutex->m));
+ if (errcode == EBUSY)
+ xbt_os_thread_yield();
+ } while (errcode == EBUSY && xbt_os_time()-start <delay);
+
+ if (errcode == EBUSY)
+ errcode = ETIMEDOUT;
+
+#endif /* HAVE_MUTEX_TIMEDLOCK */
+
+ switch (errcode) {
+ case 0:
+ return;
+
+ case ETIMEDOUT:
+ THROW2(timeout_error,delay,"mutex %p wasn't signaled before timeout (%f)",mutex,delay);
+
+ default:
+ THROW3(system_error,errcode,"pthread_mutex_timedlock(%p,%f) failed: %s",mutex,delay, strerror(errcode));
+ }
+ }
}
void xbt_os_mutex_release(xbt_os_mutex_t mutex) {
}
typedef struct xbt_os_sem_ {
- #ifndef HAVE_SEM_WAIT
+ #ifndef HAVE_SEM_INIT
char* name;
- sem_t* s;
- #else
- sem_t s;
#endif
+ sem_t s;
+ sem_t *ps;
}s_xbt_os_sem_t ;
-xbt_os_sem_t
-xbt_os_sem_init(unsigned int value)
-{
- xbt_os_sem_t res = xbt_new(s_xbt_os_sem_t,1);
- int errcode;
-
- /* On MAC OS X, it seems that the sem_init is failing with ENOSYS,
- * which means the sem_init function is not implemented use sem_open()
- * instead
- */
- #ifndef HAVE_SEM_INIT
- res->name = (char*) calloc(MAX_SEM_NAME + 1,sizeof(char));
-
- if((errcode = pthread_mutex_lock(&__next_sem_ID_lock)))
- THROW1(system_error,errcode,"pthread_mutex_lock() failed: %s", strerror(errcode));
-
- __next_sem_ID++;
-
- if((errcode = pthread_mutex_unlock(&__next_sem_ID_lock)))
- THROW1(system_error,errcode,"pthread_mutex_unlock() failed: %s", strerror(errcode));
-
- sprintf(res->name,"/%d.%d",(*xbt_getpid)(),__next_sem_ID);
+#ifndef SEM_FAILED
+#define SEM_FAILED (-1)
+#endif
- if((res->s = sem_open(res->name, O_CREAT, 0644, value)) == (sem_t*)SEM_FAILED)
- THROW1(system_error,errno,"sem_open() failed: %s",strerror(errno));
-
- if(sem_unlink(res->name) < 0)
- THROW1(system_error,errno,"sem_unlink() failed: %s", strerror(errno));
+xbt_os_sem_t
+xbt_os_sem_init(unsigned int value) {
+ xbt_os_sem_t res = xbt_new(s_xbt_os_sem_t,1);
+ /* On some systems (MAC OS X), only the stub of sem_init is to be found.
+ * Any attempt to use it leads to ENOSYS (function not implemented).
+ * If such a prehistoric system is detected, do the job with sem_open instead
+ */
+#ifdef HAVE_SEM_INIT
+ if(sem_init(&(res->s),0,value) != 0)
+ THROW1(system_error,errno,"sem_init() failed: %s", strerror(errno));
+ res->ps = &(res->s);
+
+#else /* damn, no sem_init(). Reimplement it */
+
+ xbt_os_mutex_acquire(next_sem_ID_lock);
+ res->name = bprintf("/%d.%d",(*xbt_getpid)(),++next_sem_ID);
+ xbt_os_mutex_release(next_sem_ID_lock);
+
+ res->ps = sem_open(res->name, O_CREAT, 0644, value);
+ if ((res->ps == (sem_t *)SEM_FAILED) && (errno == ENAMETOOLONG)) {
+ /* Old darwins only allow 13 chars. Did you create *that* amount of semaphores? */
+ res->name[13] = '\0';
+ res->ps = sem_open(res->name, O_CREAT, 0644, 1);
+ }
+ if ((res->ps == (sem_t *)SEM_FAILED))
+ THROW1(system_error,errno,"sem_open() failed: %s",strerror(errno));
+
+ /* Remove the name from the semaphore namespace: we never join on it */
+ if(sem_unlink(res->name) < 0)
+ THROW1(system_error,errno,"sem_unlink() failed: %s", strerror(errno));
- #else
- /* sem_init() is implemented, use it */
- if(sem_init(&(res->s),0,value) < 0)
- THROW1(system_error,errno,"sem_init() failed: %s",
- strerror(errno));
- #endif
+#endif
return res;
}
void
-xbt_os_sem_acquire(xbt_os_sem_t sem)
-{
- if(!sem)
- THROW0(arg_error,EINVAL,"Cannot acquire of the NULL semaphore");
- #ifndef HAVE_SEM_WAIT
- if(sem_wait((sem->s)) < 0)
- THROW1(system_error,errno,"sem_wait() failed: %s",
- strerror(errno));
- #else
- if(sem_wait(&(sem->s)) < 0)
- THROW1(system_error,errno,"sem_wait() failed: %s",
- strerror(errno));
- #endif
+xbt_os_sem_acquire(xbt_os_sem_t sem) {
+ if(!sem)
+ THROW0(arg_error,EINVAL,"Cannot acquire of the NULL semaphore");
+ if(sem_wait(sem->ps) < 0)
+ THROW1(system_error,errno,"sem_wait() failed: %s", strerror(errno));
}
-#ifndef HAVE_SEM_TIMEDWAIT
-/* if the function is not availabled or if is MAC OS X use sem_trywait() to define
- * it.
- */
-#include <time.h> /* declaration of the timespec structure and of the nanosleep() function */
-int sem_timedwait(sem_t* sem, const struct timespec * abs_timeout)
-{
- int rv;
- long ellapsed_time = 0;
- struct timespec ts;
-
- do
- {
- rv = sem_trywait(sem);
- ts.tv_sec = 0;
- ts.tv_nsec = 2.5e7 /* (25 ms (2 * context switch + 5 ms)) */;
-
- do
- {
- nanosleep(&ts, &ts);
- }while(EINTR == errno);
-
- ellapsed_time += ts.tv_nsec;
+void xbt_os_sem_timedacquire(xbt_os_sem_t sem, double delay) {
+ int errcode;
- }
- while(/* locked */ (EAGAIN == rv) && /* !timeout */ ellapsed_time < ((long)(abs_timeout->tv_sec * 1e9) + abs_timeout->tv_nsec));
+ if(!sem)
+ THROW0(arg_error,EINVAL,"Cannot acquire of the NULL semaphore");
- return (EAGAIN == rv) ? ETIMEDOUT : rv;
-}
+ if (delay < 0) {
+ xbt_os_sem_acquire(sem);
+ } else if (delay==0) {
+ errcode = sem_trywait(sem->ps);
+ switch (errcode) {
+ case 0:
+ return;
+ case ETIMEDOUT:
+ THROW1(timeout_error,0,"semaphore %p not ready",sem);
+ default:
+ THROW2(system_error,errcode,"xbt_sem_tryacquire(%p) failed: %s",sem, strerror(errcode));
+ }
+
+ } else {
+#ifdef HAVE_SEM_WAIT
+ struct timespec ts_end;
+ double end = delay + xbt_os_time();
+
+ ts_end.tv_sec = (time_t) floor(end);
+ ts_end.tv_nsec = (long) ( ( end - ts_end.tv_sec) * 1000000000);
+ DEBUG2("sem_timedwait(%p,%p)",sem->ps,&ts_end);
+ errcode = sem_timedwait(sem->s,&ts_end);
+
+#else /* Okay, reimplement this function then */
+ double start = xbt_os_time();
+ do {
+ errcode = sem_trywait(sem->ps);
+ if (errcode == EBUSY)
+ xbt_os_thread_yield();
+ } while (errcode == EBUSY && xbt_os_time()-start <delay);
+
+ if (errcode == EBUSY)
+ errcode = ETIMEDOUT;
#endif
+
+ switch (errcode) {
+ case 0:
+ return;
-void xbt_os_sem_timedacquire(xbt_os_sem_t sem,double timeout)
-{
- int errcode;
- struct timespec ts_end;
- double end = timeout + xbt_os_time();
-
- if(!sem)
- THROW0(arg_error,EINVAL,"Cannot acquire of the NULL semaphore");
-
- if (timeout < 0)
- {
- xbt_os_sem_acquire(sem);
- }
- else if(!timeout)
- {
- #ifndef HAVE_SEM_TIMEDWAIT
- if(sem_trywait(sem->s) < 0)
- THROW2(system_error,errno,"sem_trywait(%p) failed: %s",sem,strerror(errno));
- #else
- if(sem_trywait(&(sem->s)) < 0)
- THROW2(system_error,errno,"sem_trywait(%p) failed: %s",sem,strerror(errno));
- #endif
- }
- else
- {
- ts_end.tv_sec = (time_t) floor(end);
- ts_end.tv_nsec = (long) ( ( end - ts_end.tv_sec) * 1000000000);
- DEBUG2("sem_timedwait(%p,%p)",&(sem->s),&ts_end);
-
- #ifndef HAVE_SEM_WAIT
- switch ((errcode = sem_timedwait(sem->s,&ts_end)))
- #else
- switch ((errcode = sem_timedwait(&(sem->s),&ts_end)))
- #endif
- {
- case 0:
- return;
-
- case ETIMEDOUT:
- THROW2(timeout_error,errcode,"semaphore %p wasn't signaled before timeout (%f)",sem,timeout);
-
- default:
- THROW3(system_error,errcode,"sem_timedwait(%p,%f) failed: %s",sem,timeout, strerror(errcode));
- }
- }
+ case ETIMEDOUT:
+ THROW2(timeout_error,delay,"semaphore %p wasn't signaled before timeout (%f)",sem,delay);
+ default:
+ THROW3(system_error,errcode,"sem_timedwait(%p,%f) failed: %s",sem,delay, strerror(errcode));
+ }
+ }
}
void
if(!sem)
THROW0(arg_error,EINVAL,"Cannot release of the NULL semaphore");
- #ifndef HAVE_SEM_WAIT
- if(sem_post((sem->s)) < 0)
- THROW1(system_error,errno,"sem_post() failed: %s",
- strerror(errno));
- #else
- if(sem_post(&(sem->s)) < 0)
+ if(sem_post(sem->ps) < 0)
THROW1(system_error,errno,"sem_post() failed: %s",
strerror(errno));
- #endif
}
void
xbt_os_sem_destroy(xbt_os_sem_t sem)
{
- if(!sem)
- THROW0(arg_error,EINVAL,"Cannot destroy the NULL sempahore");
-
- #ifndef HAVE_SEM_WAIT
- /* MAC OS X does not implement the sem_init() function so,
- * we use the named semaphore (sem_open)
- */
- if(sem_close((sem->s)) < 0)
- THROW1(system_error,errno,"sem_close() failed: %s",
- strerror(errno));
+ if(!sem)
+ THROW0(arg_error,EINVAL,"Cannot destroy the NULL sempahore");
- xbt_free(sem->name);
-
- #else
- if(sem_destroy(&(sem->s)) < 0)
- THROW1(system_error,errno,"sem_destroy() failed: %s",
+#ifdef HAVE_SEM_INIT
+ if(sem_destroy(sem->ps)) < 0)
+ THROW1(system_error,errno,"sem_destroy() failed: %s",
+ strerror(errno));
+#else
+ if(sem_close(sem->ps) < 0)
+ THROW1(system_error,errno,"sem_close() failed: %s",
strerror(errno));
- #endif
+ xbt_free(sem->name);
- xbt_free(sem);
+#endif
+ xbt_free(sem);
}
void
if(!sem)
THROW0(arg_error,EINVAL,"Cannot get the value of the NULL semaphore");
- #ifndef HAVE_SEM_WAIT
- if(sem_getvalue((sem->s),svalue) < 0)
- THROW1(system_error,errno,"sem_getvalue() failed: %s",
- strerror(errno));
- #else
if(sem_getvalue(&(sem->s),svalue) < 0)
THROW1(system_error,errno,"sem_getvalue() failed: %s",
strerror(errno));
- #endif
}
/* ********************************* WINDOWS IMPLEMENTATION ************************************ */