cvs update pthreads

1 files changed, 251 insertions, 244 deletions

diff --git a/pthreads/pthread_cond_destroy.c b/pthreads/pthread_cond_destroy.c
index 3d29ffc40..34550f08d 100644
--- a/pthreads/pthread_cond_destroy.c
+++ b/pthreads/pthread_cond_destroy.c
@@ -1,244 +1,251 @@
-/*
- * pthread_cond_destroy.c
- *
- * Description:
- * This translation unit implements condition variables and their primitives.
- *
- *
- * --------------------------------------------------------------------------
- *
- *      Pthreads-win32 - POSIX Threads Library for Win32
- *      Copyright(C) 1998 John E. Bossom
- *      Copyright(C) 1999,2005 Pthreads-win32 contributors
- * 
- *      Contact Email: rpj@callisto.canberra.edu.au
- * 
- *      The current list of contributors is contained
- *      in the file CONTRIBUTORS included with the source
- *      code distribution. The list can also be seen at the
- *      following World Wide Web location:
- *      http://sources.redhat.com/pthreads-win32/contributors.html
- * 
- *      This library is free software; you can redistribute it and/or
- *      modify it under the terms of the GNU Lesser General Public
- *      License as published by the Free Software Foundation; either
- *      version 2 of the License, or (at your option) any later version.
- * 
- *      This library is distributed in the hope that it will be useful,
- *      but WITHOUT ANY WARRANTY; without even the implied warranty of
- *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- *      Lesser General Public License for more details.
- * 
- *      You should have received a copy of the GNU Lesser General Public
- *      License along with this library in the file COPYING.LIB;
- *      if not, write to the Free Software Foundation, Inc.,
- *      59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
- */
-
-#include "pthread.h"
-#include "implement.h"
-
-int
-pthread_cond_destroy (pthread_cond_t * cond)
-     /*
-      * ------------------------------------------------------
-      * DOCPUBLIC
-      *      This function destroys a condition variable
-      *
-      *
-      * PARAMETERS
-      *      cond
-      *              pointer to an instance of pthread_cond_t
-      *
-      *
-      * DESCRIPTION
-      *      This function destroys a condition variable.
-      *
-      *      NOTES:
-      *              1)      A condition variable can be destroyed
-      *                      immediately after all the threads that
-      *                      are blocked on it are awakened. e.g.
-      *
-      *                      struct list {
-      *                        pthread_mutex_t lm;
-      *                        ...
-      *                      }
-      *
-      *                      struct elt {
-      *                        key k;
-      *                        int busy;
-      *                        pthread_cond_t notbusy;
-      *                        ...
-      *                      }
-      *
-      *                      
-      *                      struct elt *
-      *                      list_find(struct list *lp, key k)
-      *                      {
-      *                        struct elt *ep;
-      *
-      *                        pthread_mutex_lock(&lp->lm);
-      *                        while ((ep = find_elt(l,k) != NULL) && ep->busy)
-      *                          pthread_cond_wait(&ep->notbusy, &lp->lm);
-      *                        if (ep != NULL)
-      *                          ep->busy = 1;
-      *                        pthread_mutex_unlock(&lp->lm);
-      *                        return(ep);
-      *                      }
-      *
-      *                      delete_elt(struct list *lp, struct elt *ep)
-      *                      {
-      *                        pthread_mutex_lock(&lp->lm);
-      *                        assert(ep->busy);
-      *                        ... remove ep from list ...
-      *                        ep->busy = 0;
-      *                    (A) pthread_cond_broadcast(&ep->notbusy);
-      *                        pthread_mutex_unlock(&lp->lm);
-      *                    (B) pthread_cond_destroy(&rp->notbusy);
-      *                        free(ep);
-      *                      }
-      *
-      *                      In this example, the condition variable
-      *                      and its list element may be freed (line B)
-      *                      immediately after all threads waiting for
-      *                      it are awakened (line A), since the mutex
-      *                      and the code ensure that no other thread
-      *                      can touch the element to be deleted.
-      *
-      * RESULTS
-      *              0               successfully released condition variable,
-      *              EINVAL          'cond' is invalid,
-      *              EBUSY           'cond' is in use,
-      *
-      * ------------------------------------------------------
-      */
-{
-  pthread_cond_t cv;
-  int result = 0, result1 = 0, result2 = 0;
-
-  /*
-   * Assuming any race condition here is harmless.
-   */
-  if (cond == NULL || *cond == NULL)
-    {
-      return EINVAL;
-    }
-
-  if (*cond != PTHREAD_COND_INITIALIZER)
-    {
-      EnterCriticalSection (&ptw32_cond_list_lock);
-
-      cv = *cond;
-
-      /*
-       * Close the gate; this will synchronize this thread with
-       * all already signaled waiters to let them retract their
-       * waiter status - SEE NOTE 1 ABOVE!!!
-       */
-      if (sem_wait (&(cv->semBlockLock)) != 0)
-	{
-	  return errno;
-	}
-
-      /*
-       * !TRY! lock mtxUnblockLock; try will detect busy condition
-       * and will not cause a deadlock with respect to concurrent
-       * signal/broadcast.
-       */
-      if ((result = pthread_mutex_trylock (&(cv->mtxUnblockLock))) != 0)
-	{
-	  (void) sem_post (&(cv->semBlockLock));
-	  return result;
-	}
-
-      /*
-       * Check whether cv is still busy (still has waiters)
-       */
-      if (cv->nWaitersBlocked > cv->nWaitersGone)
-	{
-	  if (sem_post (&(cv->semBlockLock)) != 0)
-	    {
-	      result = errno;
-	    }
-	  result1 = pthread_mutex_unlock (&(cv->mtxUnblockLock));
-	  result2 = EBUSY;
-	}
-      else
-	{
-	  /*
-	   * Now it is safe to destroy
-	   */
-	  *cond = NULL;
-
-	  if (sem_destroy (&(cv->semBlockLock)) != 0)
-	    {
-	      result = errno;
-	    }
-	  if (sem_destroy (&(cv->semBlockQueue)) != 0)
-	    {
-	      result1 = errno;
-	    }
-	  if ((result2 = pthread_mutex_unlock (&(cv->mtxUnblockLock))) == 0)
-	    {
-	      result2 = pthread_mutex_destroy (&(cv->mtxUnblockLock));
-	    }
-
-	  /* Unlink the CV from the list */
-
-	  if (ptw32_cond_list_head == cv)
-	    {
-	      ptw32_cond_list_head = cv->next;
-	    }
-	  else
-	    {
-	      cv->prev->next = cv->next;
-	    }
-
-	  if (ptw32_cond_list_tail == cv)
-	    {
-	      ptw32_cond_list_tail = cv->prev;
-	    }
-	  else
-	    {
-	      cv->next->prev = cv->prev;
-	    }
-
-	  (void) free (cv);
-	}
-
-      LeaveCriticalSection (&ptw32_cond_list_lock);
-    }
-  else
-    {
-      /*
-       * See notes in ptw32_cond_check_need_init() above also.
-       */
-      EnterCriticalSection (&ptw32_cond_test_init_lock);
-
-      /*
-       * Check again.
-       */
-      if (*cond == PTHREAD_COND_INITIALIZER)
-	{
-	  /*
-	   * This is all we need to do to destroy a statically
-	   * initialised cond that has not yet been used (initialised).
-	   * If we get to here, another thread waiting to initialise
-	   * this cond will get an EINVAL. That's OK.
-	   */
-	  *cond = NULL;
-	}
-      else
-	{
-	  /*
-	   * The cv has been initialised while we were waiting
-	   * so assume it's in use.
-	   */
-	  result = EBUSY;
-	}
-
-      LeaveCriticalSection (&ptw32_cond_test_init_lock);
-    }
-
-  return ((result != 0) ? result : ((result1 != 0) ? result1 : result2));
-}
+/*

+ * pthread_cond_destroy.c

+ *

+ * Description:

+ * This translation unit implements condition variables and their primitives.

+ *

+ *

+ * --------------------------------------------------------------------------

+ *

+ *      Pthreads-win32 - POSIX Threads Library for Win32

+ *      Copyright(C) 1998 John E. Bossom

+ *      Copyright(C) 1999,2005 Pthreads-win32 contributors

+ * 

+ *      Contact Email: rpj@callisto.canberra.edu.au

+ * 

+ *      The current list of contributors is contained

+ *      in the file CONTRIBUTORS included with the source

+ *      code distribution. The list can also be seen at the

+ *      following World Wide Web location:

+ *      http://sources.redhat.com/pthreads-win32/contributors.html

+ * 

+ *      This library is free software; you can redistribute it and/or

+ *      modify it under the terms of the GNU Lesser General Public

+ *      License as published by the Free Software Foundation; either

+ *      version 2 of the License, or (at your option) any later version.

+ * 

+ *      This library is distributed in the hope that it will be useful,

+ *      but WITHOUT ANY WARRANTY; without even the implied warranty of

+ *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

+ *      Lesser General Public License for more details.

+ * 

+ *      You should have received a copy of the GNU Lesser General Public

+ *      License along with this library in the file COPYING.LIB;

+ *      if not, write to the Free Software Foundation, Inc.,

+ *      59 Temple Place - Suite 330, Boston, MA 02111-1307, USA

+ */

+

+#include "pthread.h"

+#include "implement.h"

+

+int

+pthread_cond_destroy (pthread_cond_t * cond)

+     /*

+      * ------------------------------------------------------

+      * DOCPUBLIC

+      *      This function destroys a condition variable

+      *

+      *

+      * PARAMETERS

+      *      cond

+      *              pointer to an instance of pthread_cond_t

+      *

+      *

+      * DESCRIPTION

+      *      This function destroys a condition variable.

+      *

+      *      NOTES:

+      *              1)      A condition variable can be destroyed

+      *                      immediately after all the threads that

+      *                      are blocked on it are awakened. e.g.

+      *

+      *                      struct list {

+      *                        pthread_mutex_t lm;

+      *                        ...

+      *                      }

+      *

+      *                      struct elt {

+      *                        key k;

+      *                        int busy;

+      *                        pthread_cond_t notbusy;

+      *                        ...

+      *                      }

+      *

+      *                      

+      *                      struct elt *

+      *                      list_find(struct list *lp, key k)

+      *                      {

+      *                        struct elt *ep;

+      *

+      *                        pthread_mutex_lock(&lp->lm);

+      *                        while ((ep = find_elt(l,k) != NULL) && ep->busy)

+      *                          pthread_cond_wait(&ep->notbusy, &lp->lm);

+      *                        if (ep != NULL)

+      *                          ep->busy = 1;

+      *                        pthread_mutex_unlock(&lp->lm);

+      *                        return(ep);

+      *                      }

+      *

+      *                      delete_elt(struct list *lp, struct elt *ep)

+      *                      {

+      *                        pthread_mutex_lock(&lp->lm);

+      *                        assert(ep->busy);

+      *                        ... remove ep from list ...

+      *                        ep->busy = 0;

+      *                    (A) pthread_cond_broadcast(&ep->notbusy);

+      *                        pthread_mutex_unlock(&lp->lm);

+      *                    (B) pthread_cond_destroy(&rp->notbusy);

+      *                        free(ep);

+      *                      }

+      *

+      *                      In this example, the condition variable

+      *                      and its list element may be freed (line B)

+      *                      immediately after all threads waiting for

+      *                      it are awakened (line A), since the mutex

+      *                      and the code ensure that no other thread

+      *                      can touch the element to be deleted.

+      *

+      * RESULTS

+      *              0               successfully released condition variable,

+      *              EINVAL          'cond' is invalid,

+      *              EBUSY           'cond' is in use,

+      *

+      * ------------------------------------------------------

+      */

+{

+  pthread_cond_t cv;

+  int result = 0, result1 = 0, result2 = 0;

+

+  /*

+   * Assuming any race condition here is harmless.

+   */

+  if (cond == NULL || *cond == NULL)

+    {

+      return EINVAL;

+    }

+

+  if (*cond != PTHREAD_COND_INITIALIZER)

+    {

+      EnterCriticalSection (&ptw32_cond_list_lock);

+

+      cv = *cond;

+

+      /*

+       * Close the gate; this will synchronize this thread with

+       * all already signaled waiters to let them retract their

+       * waiter status - SEE NOTE 1 ABOVE!!!

+       */

+      if (ptw32_semwait (&(cv->semBlockLock)) != 0) /* Non-cancelable */

+	{

+	  result = errno;

+	}

+      else

+        {

+          /*

+           * !TRY! lock mtxUnblockLock; try will detect busy condition

+           * and will not cause a deadlock with respect to concurrent

+           * signal/broadcast.

+           */

+          if ((result = pthread_mutex_trylock (&(cv->mtxUnblockLock))) != 0)

+	    {

+	      (void) sem_post (&(cv->semBlockLock));

+	    }

+	}

+	

+      if (result != 0)

+        {

+          LeaveCriticalSection (&ptw32_cond_list_lock);

+          return result;

+        }

+

+      /*

+       * Check whether cv is still busy (still has waiters)

+       */

+      if (cv->nWaitersBlocked > cv->nWaitersGone)

+	{

+	  if (sem_post (&(cv->semBlockLock)) != 0)

+	    {

+	      result = errno;

+	    }

+	  result1 = pthread_mutex_unlock (&(cv->mtxUnblockLock));

+	  result2 = EBUSY;

+	}

+      else

+	{

+	  /*

+	   * Now it is safe to destroy

+	   */

+	  *cond = NULL;

+

+	  if (sem_destroy (&(cv->semBlockLock)) != 0)

+	    {

+	      result = errno;

+	    }

+	  if (sem_destroy (&(cv->semBlockQueue)) != 0)

+	    {

+	      result1 = errno;

+	    }

+	  if ((result2 = pthread_mutex_unlock (&(cv->mtxUnblockLock))) == 0)

+	    {

+	      result2 = pthread_mutex_destroy (&(cv->mtxUnblockLock));

+	    }

+

+	  /* Unlink the CV from the list */

+

+	  if (ptw32_cond_list_head == cv)

+	    {

+	      ptw32_cond_list_head = cv->next;

+	    }

+	  else

+	    {

+	      cv->prev->next = cv->next;

+	    }

+

+	  if (ptw32_cond_list_tail == cv)

+	    {

+	      ptw32_cond_list_tail = cv->prev;

+	    }

+	  else

+	    {

+	      cv->next->prev = cv->prev;

+	    }

+

+	  (void) free (cv);

+	}

+

+      LeaveCriticalSection (&ptw32_cond_list_lock);

+    }

+  else

+    {

+      /*

+       * See notes in ptw32_cond_check_need_init() above also.

+       */

+      EnterCriticalSection (&ptw32_cond_test_init_lock);

+

+      /*

+       * Check again.

+       */

+      if (*cond == PTHREAD_COND_INITIALIZER)

+	{

+	  /*

+	   * This is all we need to do to destroy a statically

+	   * initialised cond that has not yet been used (initialised).

+	   * If we get to here, another thread waiting to initialise

+	   * this cond will get an EINVAL. That's OK.

+	   */

+	  *cond = NULL;

+	}

+      else

+	{

+	  /*

+	   * The cv has been initialised while we were waiting

+	   * so assume it's in use.

+	   */

+	  result = EBUSY;

+	}

+

+      LeaveCriticalSection (&ptw32_cond_test_init_lock);

+    }

+

+  return ((result != 0) ? result : ((result1 != 0) ? result1 : result2));

+}