C++ sem_create函数代码示例

int main (int argc, char *argv[])
{
   printf ("Main INICIO\n") ;

   task_init () ;

   sem_create (&s1, 1) ;
   sem_create (&s2, 0) ;

   task_create (&a1, TaskA, "A1") ;
   task_create (&a2, TaskA, "  A2") ;
   task_create (&b1, TaskB, "             B1") ;
   task_create (&b2, TaskB, "               B2") ;

   task_join (&a1) ;

   sem_destroy (&s1) ;
   sem_destroy (&s2) ;

   task_join (&a2) ;
   task_join (&b1) ;
   task_join (&b2) ;

   printf ("Main FIM\n") ;
   task_exit (0) ;

   exit (0) ;
}

static
void
inititems(void)
{
	if (BrSem==NULL) {
		BrSem = sem_create("BrSem", 3);
		if (BrSem == NULL) {
			panic("BrSem: sem_create failed\n");
		}
	}
	if (doneSem==NULL) {
		doneSem = sem_create("doneSem", 0);
		if (doneSem == NULL) {
			panic("synchtest: sem_create failed\n");
		}
	}
	if (BrLock==NULL) {
		BrLock = lock_create("BrLock");
		if (BrLock == NULL) {
			panic("BrLock: lock_create failed\n");
		}
	}
	if (boyCV==NULL) {
		boyCV = cv_create("boyCV");
		if (boyCV == NULL) {
			panic("boyCV: cv_create failed\n");
		}
	}
	if (girlCV==NULL) {
		girlCV = cv_create("girlCV");
		if (girlCV == NULL) {
			panic("girlCV: cv_create failed\n");
		}
	}
}

int
elves(int nargs, char **args)
{
	unsigned num_elves;

	// if an argument is passed, use that as the number of elves
	num_elves = 10;
	if (nargs == 2) {
		num_elves = atoi(args[1]);
	}

	// Suppress unused warnings. Remove these when finished.
	(void) work;
	(void) supervisor;
	(void) elf;
    (void) num_elves;
	// TODO

	print_lock = sem_create("print", 1);
	elf_lock = sem_create("elf", num_elves);
	complete_lock = sem_create("complete_lk", 1);
	elf_complete = -1;

	kprintf("Starting up Keebler Factory!\n");
	supervisor(NULL, num_elves);

	return 0;
}

/*
 * Setup routine called by autoconf.c when an lhd is found.
 */
int
config_lhd(struct lhd_softc *lh, int lhdno)
{
	char name[32];

	/* Figure out what our name is. */
	snprintf(name, sizeof(name), "lhd%d", lhdno);

	/* Get a pointer to the on-chip buffer. */
	lh->lh_buf = bus_map_area(lh->lh_busdata, lh->lh_buspos, LHD_BUFFER);

	/* Create the semaphores. */
	lh->lh_clear = sem_create("lhd-clear", 1);
	if (lh->lh_clear == NULL) {
		return ENOMEM;
	}
	lh->lh_done = sem_create("lhd-done", 0);
	if (lh->lh_done == NULL) {
		sem_destroy(lh->lh_clear);
		lh->lh_clear = NULL;
		return ENOMEM;
	}

	/* Set up the VFS device structure. */
	lh->lh_dev.d_ops = &lhd_devops;
	lh->lh_dev.d_blocks = bus_read_register(lh->lh_busdata, lh->lh_buspos,
						LHD_REG_NSECT);
	lh->lh_dev.d_blocksize = LHD_SECTSIZE;
	lh->lh_dev.d_data = lh;

	/* Add the VFS device structure to the VFS device list. */
	return vfs_adddev(name, &lh->lh_dev, 1);
}

static
void
inititems(void)
{
	if (testsem==NULL) {
		testsem = sem_create("testsem", 2);
		if (testsem == NULL) {
			panic("synchtest: sem_create failed\n");
		}
	}
	if (testlock==NULL) {
		testlock = lock_create("testlock");
		if (testlock == NULL) {
			panic("synchtest: lock_create failed\n");
		}
	}
	if (testcv==NULL) {
		testcv = cv_create("testlock");
		if (testcv == NULL) {
			panic("synchtest: cv_create failed\n");
		}
	}
	if (donesem==NULL) {
		donesem = sem_create("donesem", 0);
		if (donesem == NULL) {
			panic("synchtest: sem_create failed\n");
		}
	}
}

void createSemaphores(void) {
	sem_create(smutex, 1);
	sem_create(sage, 0);
	sem_create(stob, 0);
	sem_create(spap, 0);
	sem_create(smat, 0);

}

static struct pipefs_vnode *pipefs_create_vnode(struct pipefs *fs, const char *name, stream_type type)
{
	struct pipefs_vnode *v;

	v = kmalloc(sizeof(struct pipefs_vnode));
	if(v == NULL)
		return NULL;

	memset(v, 0, sizeof(struct pipefs_vnode));
	v->id = atomic_add(&fs->next_vnode_id, 1);

	v->name = kstrdup(name);
	if(v->name == NULL)
		goto err;

	v->stream.type = type;
	switch(type) {
		case STREAM_TYPE_DIR:
			v->stream.u.dir.dir_head = NULL;
			v->stream.u.dir.jar_head = NULL;
			if(mutex_init(&v->stream.u.dir.dir_lock, "pipefs_dir_lock") < 0)
				goto err;
			break;
		case STREAM_TYPE_PIPE:
			v->stream.u.pipe.buf = kmalloc(PIPE_BUFFER_LEN);
			if(v->stream.u.pipe.buf == NULL)
				goto err;
			v->stream.u.pipe.buf_len = PIPE_BUFFER_LEN;

			if(mutex_init(&v->stream.u.pipe.lock, "pipe_lock") < 0) {
				kfree(v->stream.u.pipe.buf);
				goto err;
			}
			v->stream.u.pipe.read_sem = sem_create(0, "pipe_read_sem");
			if(v->stream.u.pipe.read_sem < 0) {
				mutex_destroy(&v->stream.u.pipe.lock);
				kfree(v->stream.u.pipe.buf);
				goto err;
			}
			v->stream.u.pipe.write_sem = sem_create(1, "pipe_write_sem");
			if(v->stream.u.pipe.write_sem < 0) {
				sem_delete(v->stream.u.pipe.read_sem);
				mutex_destroy(&v->stream.u.pipe.lock);
				kfree(v->stream.u.pipe.buf);
				goto err;
			}
			break;
	}

	return v;

err:
	if(v->name)
		kfree(v->name);
	kfree(v);
	return NULL;
}

void whalemating_init() {
 hold=lock_create("My lock");
 male_sem=sem_create("Male Semaphore",0);
 female_sem=sem_create("Female Semaphore",0);
mate_cv=cv_create("mating cv");
male_count=0;
female_count=0;
  return;
}

int
config_con(struct con_softc *cs, int unit)
{
	struct semaphore *rsem, *wsem;
	struct lock *rlk, *wlk;

	/*
	 * Only allow one system console.
	 * Further devices that could be the system console are ignored.
	 *
	 * Do not hardwire the console to be "con1" instead of "con0",
	 * or these asserts will go off.
	 */
	if (unit>0) {
		KASSERT(the_console!=NULL);
		return ENODEV;
	}
	KASSERT(the_console==NULL);

	rsem = sem_create("console read", 0);
	if (rsem == NULL) {
		return ENOMEM;
	}
	wsem = sem_create("console write", 1);
	if (wsem == NULL) {
		sem_destroy(rsem);
		return ENOMEM;
	}
	rlk = lock_create("console-lock-read");
	if (rlk == NULL) {
		sem_destroy(rsem);
		sem_destroy(wsem);
		return ENOMEM;
	}
	wlk = lock_create("console-lock-write");
	if (wlk == NULL) {
		lock_destroy(rlk);
		sem_destroy(rsem);
		sem_destroy(wsem);
		return ENOMEM;
	}

	cs->cs_rsem = rsem;
	cs->cs_wsem = wsem;
	cs->cs_gotchars_head = 0;
	cs->cs_gotchars_tail = 0;

	the_console = cs;
	con_userlock_read = rlk;
	con_userlock_write = wlk;

	flush_delay_buf();

	return attach_console_to_vfs(cs);
}

void stoplight_init() {

  for(int i=0; i<DIRECTIONS;i++)
  {
    if(quadSem[i]==NULL){
      quadSem[i] = sem_create("Quadrant Semaphore",1);
      if (quadSem[i] == NULL) {
        panic("synchtest: sem_create failed at quadSem\n");
      }
    }
  }

  if(mutex==NULL){
	  mutex = sem_create("mutex Semaphore",1);
        if (mutex == NULL) {
          panic("synchtest: sem_create failed at quadSem\n");
        }
      }
  j[0]=0;
  j[1]=0;
  j[2]=0;
  j[3]=0;
  head[0]=1;
  head[1]=1;
  head[2]=1;
  head[3]=1;

  jlock=lock_create("j1lock");
  /*jl[1]=lock_create("j2lock");
  jl[2]=lock_create("j3lock");
  jl[3]=lock_create("j4lock");
*/
/*  if(quadSem1==NULL){
    quadSem1 = sem_create("Quadrant 1 Semaphore",0);
    if (quadSem1 == NULL) {
      panic("synchtest: sem_create failed at quadSem1\n");
    }
  }
  if(quadSem2==NULL){
    quadSem2 = sem_create("Quadrant 2 Semaphore",0);
    if (quadSem2 == NULL) {
      panic("synchtest: sem_create failed at quadSem2\n");
    }
  }
  if(quadSem3==NULL){
    quadSem3 = sem_create("Quadrant 3 Semaphore",0);
    if (quadSem3 == NULL) {
      panic("synchtest: sem_create failed at quadSem3\n");
    }
  }
*/
  return;
}

qsem_t *qsem_create (int count)
{
	qsem_t *s;

	s = (qsem_t *) malloc (sizeof (qsem_t));
#ifdef I386
	s->mutex = sem_create (count, "qsem_mutex");
	s->count = 0;
#else
	s->mutex = sem_create (0, "qsem_mutex");
	s->count = count;
#endif
	return s;
}

void test161_bootstrap()
{
	test161_sem = sem_create("test161", 1);
	if (test161_sem == NULL) {
		panic("Failed to create test161 secprintf semaphore");
	}
}

int
kmallocstress(int nargs, char **args)
{
	struct semaphore *sem;
	int i, result;

	(void)nargs;
	(void)args;

	sem = sem_create("kmallocstress", 0);
	if (sem == NULL) {
		panic("kmallocstress: sem_create failed\n");
	}

	kprintf("Starting kmalloc stress test...\n");

	for (i=0; i<NTHREADS; i++) {
		result = thread_fork("kmallocstress", NULL,
				     kmallocthread, sem, i);
		if (result) {
			panic("kmallocstress: thread_fork failed: %s\n",
			      strerror(result));
		}
	}

	for (i=0; i<NTHREADS; i++) {
		P(sem);
	}

	sem_destroy(sem);
	kprintf("\n");
	success(TEST161_SUCCESS, SECRET, "km2");

	return 0;
}

static
void
initiateMating()
{
	if (mateLock==NULL) {
		mateLock = lock_create("mateLock");
		if (mateLock == NULL) {
			panic("mateLock: lock_create failed\n");
		}
	}
	if (male_go==NULL) {
		male_go = cv_create("male_go");
		if (male_go == NULL) {
			panic("male_go: cv_create failed\n");
		}
	}
	if (female_go==NULL) {
		female_go = cv_create("female_go");
		if (female_go == NULL) {
			panic("female_go: cv_create failed\n");
		}
	}
	if (matchmaker_go==NULL) {
		matchmaker_go = cv_create("matchmaker_go");
		if (matchmaker_go == NULL) {
			panic("matchmaker_go: cv_create failed\n");
		}
	}
	if (doneSem==NULL) {
		doneSem = sem_create("doneSem", 0);
		if (doneSem == NULL) {
			panic("doneSem: sem_create failed\n");
		}
	}
}

gpointer
ves_icall_System_Threading_Semaphore_CreateSemaphore_internal (gint32 initialCount, gint32 maximumCount, MonoString *name, gint32 *error)
{ 
	gpointer sem;

	if (maximumCount <= 0) {
		mono_trace (G_LOG_LEVEL_DEBUG, MONO_TRACE_IO_LAYER, "%s: maximumCount <= 0", __func__);

		*error = ERROR_INVALID_PARAMETER;
		return NULL;
	}

	if (initialCount > maximumCount || initialCount < 0) {
		mono_trace (G_LOG_LEVEL_DEBUG, MONO_TRACE_IO_LAYER, "%s: initialCount > maximumCount or < 0", __func__);

		*error = ERROR_INVALID_PARAMETER;
		return NULL;
	}

	/* Need to blow away any old errors here, because code tests
	 * for ERROR_ALREADY_EXISTS on success (!) to see if a
	 * semaphore was freshly created
	 */
	SetLastError (ERROR_SUCCESS);

	if (!name)
		sem = sem_create (initialCount, maximumCount);
	else
		sem = namedsem_create (initialCount, maximumCount, mono_string_chars (name));

	*error = GetLastError ();

	return sem;
}