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authorrpj <rpj>2001-06-07 08:27:44 +0000
committerrpj <rpj>2001-06-07 08:27:44 +0000
commitcde63164e7f952ed0980fe62877796b81f749310 (patch)
treeb20099e176283639e7a62f720e7c137d9c16fa8e
parent544c9bdc635a5ce92418ee58e71cf54ba50a60a1 (diff)
* semaphore.h (sem_t): Is now an opaque pointer;
moved actual definition to implement.h. * implement.h (sem_t_): Move here from semaphore.h; was the definition of sem_t. * semaphore.c: Wherever necessary, changed use of sem from that of a pointer to a pointer-pointer; added extra checks for a valid sem_t; NULL sem_t when it is destroyed; added extra checks when creating and destroying sem_t elements in the NEED_SEM code branches; changed from using a pthread_mutex_t ((*sem)->mutex) to CRITICAL_SECTION ((*sem)->sem_lock_cs) in NEED_SEM branches for access serialisation.
-rw-r--r--ChangeLog16
-rw-r--r--implement.h12
-rw-r--r--semaphore.c139
-rw-r--r--semaphore.h11
4 files changed, 106 insertions, 72 deletions
diff --git a/ChangeLog b/ChangeLog
index e47caee..013c3e9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,20 @@
2001-06-06 Ross Johnson <rpj@setup1.ise.canberra.edu.au>
+ * semaphore.h (sem_t): Is now an opaque pointer;
+ moved actual definition to implement.h.
+ * implement.h (sem_t_): Move here from semaphore.h;
+ was the definition of sem_t.
+ * semaphore.c: Wherever necessary, changed use of sem
+ from that of a pointer to a pointer-pointer; added
+ extra checks for a valid sem_t; NULL sem_t when
+ it is destroyed; added extra checks when creating
+ and destroying sem_t elements in the NEED_SEM
+ code branches; changed from using a pthread_mutex_t
+ ((*sem)->mutex) to CRITICAL_SECTION ((*sem)->sem_lock_cs)
+ in NEED_SEM branches for access serialisation.
+
+2001-06-06 Ross Johnson <rpj@setup1.ise.canberra.edu.au>
+
* mutex.c (pthread_mutexattr_init): Remove
ptw32_mutex_default_kind.
@@ -3086,4 +3101,3 @@ Sat Jul 11 14:48:54 1998 Ross Johnson <rpj@ixobrychus.canberra.edu.au>
* create.c (pthread_create): A dummy stub right now.
* pthread.h (pthread_create): Add function prototype.
-
diff --git a/implement.h b/implement.h
index 1b57b60..9518f9e 100644
--- a/implement.h
+++ b/implement.h
@@ -114,11 +114,21 @@ struct pthread_attr_t_ {
/*
* ====================
* ====================
- * Mutexes and Condition Variables
+ * Semaphores, Mutexes and Condition Variables
* ====================
* ====================
*/
+#ifdef NEED_SEM
+typedef struct {
+ unsigned int value;
+ CRITICAL_SECTION sem_lock_cs;
+ HANDLE event;
+} sem_t_;
+#else /* NEED_SEM */
+typedef HANDLE sem_t_;
+#endif /* NEED_SEM */
+
#define PTW32_OBJECT_AUTO_INIT ((void *) -1)
#define PTW32_OBJECT_INVALID NULL
diff --git a/semaphore.c b/semaphore.c
index 15441e8..0f06c4b 100644
--- a/semaphore.c
+++ b/semaphore.c
@@ -9,18 +9,6 @@
*
* POSIX 1003.1b-1993 (POSIX.1b)
*
- * Contents:
- * Public Methods Author
- * -------------- ------
- * sem_init John E. Bossom Mar 1998
- * sem_destroy John E. Bossom Mar 1998
- * sem_trywait John E. Bossom Mar 1998
- * sem_wait John E. Bossom Mar 1998
- * sem_post John E. Bossom Mar 1998
- *
- * Private Methods
- * ---------------
- *
* -------------------------------------------------------------
*
* Pthreads-win32 - POSIX Threads Library for Win32
@@ -104,29 +92,46 @@ sem_init (sem_t * sem, int pshared, unsigned int value)
#ifdef NEED_SEM
- sem->value = value;
- pthread_mutex_init(&sem->mutex, NULL);
- sem->event = CreateEvent (NULL,
- FALSE, /* manual reset */
- FALSE, /* initial state */
- NULL);
- if (value != 0)
+ sem_t s = (sem_t) calloc (1, sizeof (*sem_t));
+
+ if (s == NULL)
{
- SetEvent(sem->event);
+ result = ENOMEM;
}
+ else
+ {
+ s->value = value;
+ s->event = CreateEvent (NULL,
+ FALSE, /* manual reset */
+ FALSE, /* initial state */
+ NULL);
+ if (s->Event == 0)
+ {
+ result = ENOSPC;
+ }
+ else
+ {
+ if (value != 0)
+ {
+ SetEvent(s->event);
+ }
+ InitializeCriticalSection(&s->sem_lock_cs);
+
+ *sem = s;
+ }
#else /* NEED_SEM */
/*
* NOTE: Taking advantage of the fact that
- * sem_t is a simple structure with one entry;
- * We don't have to allocate it...
+ * sem_t is a simple structure with one entry;
+ * We don't have to allocate it...
*/
*sem = CreateSemaphore (
- 0,
- value,
- 0x7FFFFFF,
- NULL);
+ 0,
+ value,
+ 0x7FFFFFF,
+ NULL);
if (*sem == 0)
{
@@ -175,34 +180,42 @@ sem_destroy (sem_t * sem)
*/
{
int result = 0;
+ sem_t s = *sem;
- if (sem == NULL)
+ if (sem == NULL || *sem == NULL)
{
result = EINVAL;
}
+ else
+ {
+ *sem = NULL;
#ifdef NEED_SEM
- else
- {
- pthread_mutex_destroy(&sem->mutex);
- if (!CloseHandle(sem->event))
+ if (! CloseHandle(s->event))
{
result = EINVAL;
}
- }
+ else
+ {
+ DeleteCriticalSection(&s->sem_lock_cs);
+ free(s);
+ }
#else /* NEED_SEM */
- else if (! CloseHandle (*sem))
- {
- result = EINVAL;
- }
+ if (! CloseHandle (s))
+ {
+ result = EINVAL;
+ }
#endif /* NEED_SEM */
+ }
+
if (result != 0)
{
+ *sem = s;
errno = result;
return -1;
}
@@ -242,28 +255,27 @@ sem_trywait (sem_t * sem)
* ------------------------------------------------------
*/
{
- int result = 0;
-
- if (sem == NULL)
- {
- result = EINVAL;
- }
-
#ifdef NEED_SEM
- /* not yet implemented! */
- result = EINVAL;
+ /*
+ * not yet implemented!
+ */
+ int result = EINVAL;
return -1;
#else /* NEED_SEM */
+ int result = 0;
+
+ if (sem == NULL || *sem == NULL)
+ {
+ result = EINVAL;
+ }
else if (WaitForSingleObject (*sem, 0) == WAIT_TIMEOUT)
{
result = EAGAIN;
}
-#endif /* NEED_SEM */
-
if (result != 0)
{
errno = result;
@@ -272,6 +284,8 @@ sem_trywait (sem_t * sem)
return 0;
+#endif /* NEED_SEM */
+
} /* sem_trywait */
@@ -280,14 +294,16 @@ sem_trywait (sem_t * sem)
void
ptw32_decrease_semaphore(sem_t * sem)
{
- pthread_mutex_lock(&sem->mutex);
+ register sem_t s = *sem;
+
+ EnterCriticalSection(&s->sem_lock_cs);
- if (sem->value != 0)
+ if (s->value != 0)
{
- sem->value--;
- if (sem->value != 0)
+ s->value--;
+ if (s->value != 0)
{
- SetEvent(sem->event);
+ SetEvent(s->event);
}
}
else
@@ -295,20 +311,21 @@ ptw32_decrease_semaphore(sem_t * sem)
/* this case should not happen! */
}
- pthread_mutex_unlock(&sem->mutex);
+ LeaveCriticalSection(&s->sem_lock_cs);
}
BOOL
ptw32_increase_semaphore(sem_t * sem, unsigned int n)
{
BOOL result;
+ register sem_t s = *sem;
- pthread_mutex_lock(&sem->mutex);
+ EnterCriticalSection(&s->sem_lock_cs);
- if (sem->value + n > sem->value)
+ if (s->value + n > s->value)
{
- sem->value += n;
- SetEvent(sem->event);
+ s->value += n;
+ SetEvent(s->event);
result = TRUE;
}
else
@@ -316,7 +333,7 @@ ptw32_increase_semaphore(sem_t * sem, unsigned int n)
result = FALSE;
}
- pthread_mutex_unlock(&sem->mutex);
+ LeaveCriticalSection(&s->sem_lock_cs);
return result;
}
@@ -355,7 +372,7 @@ sem_wait (sem_t * sem)
{
int result = 0;
- if (sem == NULL)
+ if (sem == NULL || *sem == NULL)
{
result = EINVAL;
}
@@ -364,7 +381,7 @@ sem_wait (sem_t * sem)
#ifdef NEED_SEM
- result = pthreadCancelableWait (sem->event);
+ result = pthreadCancelableWait ((*sem)->event);
#else /* NEED_SEM */
@@ -419,7 +436,7 @@ sem_post (sem_t * sem)
{
int result = 0;
- if (sem == NULL)
+ if (sem == NULL || *sem == NULL)
{
result = EINVAL;
}
diff --git a/semaphore.h b/semaphore.h
index bc66e35..3616b11 100644
--- a/semaphore.h
+++ b/semaphore.h
@@ -64,15 +64,8 @@ extern "C"
typedef unsigned int mode_t;
#endif
-#ifdef NEED_SEM
-typedef struct {
- unsigned int value;
- pthread_mutex_t mutex;
- HANDLE event;
-} sem_t;
-#else /* NEED_SEM */
-typedef HANDLE sem_t;
-#endif /* NEED_SEM */
+
+typedef sem_t_ * sem_t;
int sem_init (sem_t * sem,
int pshared,