cvs version of pthreads

1 files changed, 189 insertions, 188 deletions

diff --git a/pthreads/pthread_cancel.c b/pthreads/pthread_cancel.c
index d1f281bb0..ae60b7293 100644
--- a/pthreads/pthread_cancel.c
+++ b/pthreads/pthread_cancel.c
@@ -1,188 +1,189 @@
-/*

- * pthread_cancel.c

- *

- * Description:

- * POSIX thread functions related to thread cancellation.

- *

- * --------------------------------------------------------------------------

- *

- *      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"

-#include "context.h"

-

-static void

-ptw32_cancel_self (void)

-{

-  ptw32_throw (PTW32_EPS_CANCEL);

-

-  /* Never reached */

-}

-

-static void CALLBACK

-ptw32_cancel_callback (DWORD unused)

-{

-  ptw32_throw (PTW32_EPS_CANCEL);

-

-  /* Never reached */

-}

-

-/*

- * ptw32_RegisterCancelation() -

- * Must have args of same type as QueueUserAPCEx because this function

- * is a substitute for QueueUserAPCEx if it's not available.

- */

-DWORD

-ptw32_RegisterCancelation (PAPCFUNC unused1, HANDLE threadH, DWORD unused2)

-{

-  CONTEXT context;

-

-  context.ContextFlags = CONTEXT_CONTROL;

-  GetThreadContext (threadH, &context);

-  PTW32_PROGCTR (context) = (DWORD_PTR) ptw32_cancel_self;

-  SetThreadContext (threadH, &context);

-  return 0;

-}

-

-int

-pthread_cancel (pthread_t thread)

-     /*

-      * ------------------------------------------------------

-      * DOCPUBLIC

-      *      This function requests cancellation of 'thread'.

-      *

-      * PARAMETERS

-      *      thread

-      *              reference to an instance of pthread_t

-      *

-      *

-      * DESCRIPTION

-      *      This function requests cancellation of 'thread'.

-      *      NOTE: cancellation is asynchronous; use pthread_join to

-      *                wait for termination of 'thread' if necessary.

-      *

-      * RESULTS

-      *              0               successfully requested cancellation,

-      *              ESRCH           no thread found corresponding to 'thread',

-      *              ENOMEM          implicit self thread create failed.

-      * ------------------------------------------------------

-      */

-{

-  int result;

-  int cancel_self;

-  pthread_t self;

-  ptw32_thread_t * tp;

-

-  result = pthread_kill (thread, 0);

-

-  if (0 != result)

-    {

-      return result;

-    }

-

-  if ((self = pthread_self ()).p == NULL)

-    {

-      return ENOMEM;

-    };

-

-  /*

-   * For self cancellation we need to ensure that a thread can't

-   * deadlock itself trying to cancel itself asynchronously

-   * (pthread_cancel is required to be an async-cancel

-   * safe function).

-   */

-  cancel_self = pthread_equal (thread, self);

-

-  tp = (ptw32_thread_t *) thread.p;

-

-  /*

-   * Lock for async-cancel safety.

-   */

-  (void) pthread_mutex_lock (&tp->cancelLock);

-

-  if (tp->cancelType == PTHREAD_CANCEL_ASYNCHRONOUS

-      && tp->cancelState == PTHREAD_CANCEL_ENABLE

-      && tp->state < PThreadStateCanceling)

-    {

-      if (cancel_self)

-	{

-	  tp->state = PThreadStateCanceling;

-	  tp->cancelState = PTHREAD_CANCEL_DISABLE;

-

-	  (void) pthread_mutex_unlock (&tp->cancelLock);

-	  ptw32_throw (PTW32_EPS_CANCEL);

-

-	  /* Never reached */

-	}

-      else

-	{

-	  HANDLE threadH = tp->threadH;

-

-	  SuspendThread (threadH);

-

-	  if (WaitForSingleObject (threadH, 0) == WAIT_TIMEOUT)

-	    {

-	      tp->state = PThreadStateCanceling;

-	      tp->cancelState = PTHREAD_CANCEL_DISABLE;

-	      /*

-	       * If alertdrv and QueueUserAPCEx is available then the following

-	       * will result in a call to QueueUserAPCEx with the args given, otherwise

-	       * this will result in a call to ptw32_RegisterCancelation and only

-	       * the threadH arg will be used.

-	       */

-	      ptw32_register_cancelation (ptw32_cancel_callback, threadH, 0);

-	      (void) pthread_mutex_unlock (&tp->cancelLock);

-	      ResumeThread (threadH);

-	    }

-	}

-    }

-  else

-    {

-      /*

-       * Set for deferred cancellation.

-       */

-      if (tp->state < PThreadStateCancelPending)

-	{

-	  tp->state = PThreadStateCancelPending;

-	  if (!SetEvent (tp->cancelEvent))

-	    {

-	      result = ESRCH;

-	    }

-	}

-      else if (tp->state >= PThreadStateCanceling)

-	{

-	  result = ESRCH;

-	}

-

-      (void) pthread_mutex_unlock (&tp->cancelLock);

-    }

-

-  return (result);

-}

+/*
+ * pthread_cancel.c
+ *
+ * Description:
+ * POSIX thread functions related to thread cancellation.
+ *
+ * --------------------------------------------------------------------------
+ *
+ *      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"
+#include "context.h"
+
+static void
+ptw32_cancel_self (void)
+{
+  ptw32_throw (PTW32_EPS_CANCEL);
+
+  /* Never reached */
+}
+
+static void CALLBACK
+ptw32_cancel_callback (ULONG_PTR unused)
+{
+  ptw32_throw (PTW32_EPS_CANCEL);
+
+  /* Never reached */
+}
+
+/*
+ * ptw32_RegisterCancelation() -
+ * Must have args of same type as QueueUserAPCEx because this function
+ * is a substitute for QueueUserAPCEx if it's not available.
+ */
+DWORD
+ptw32_RegisterCancelation (PAPCFUNC unused1, HANDLE threadH, DWORD unused2)
+{
+  CONTEXT context;
+
+  context.ContextFlags = CONTEXT_CONTROL;
+  GetThreadContext (threadH, &context);
+  PTW32_PROGCTR (context) = (DWORD_PTR) ptw32_cancel_self;
+  SetThreadContext (threadH, &context);
+  return 0;
+}
+
+int
+pthread_cancel (pthread_t thread)
+     /*
+      * ------------------------------------------------------
+      * DOCPUBLIC
+      *      This function requests cancellation of 'thread'.
+      *
+      * PARAMETERS
+      *      thread
+      *              reference to an instance of pthread_t
+      *
+      *
+      * DESCRIPTION
+      *      This function requests cancellation of 'thread'.
+      *      NOTE: cancellation is asynchronous; use pthread_join to
+      *                wait for termination of 'thread' if necessary.
+      *
+      * RESULTS
+      *              0               successfully requested cancellation,
+      *              ESRCH           no thread found corresponding to 'thread',
+      *              ENOMEM          implicit self thread create failed.
+      * ------------------------------------------------------
+      */
+{
+  int result;
+  int cancel_self;
+  pthread_t self;
+  ptw32_thread_t * tp;
+  ptw32_mcs_local_node_t stateLock;
+
+  result = pthread_kill (thread, 0);
+
+  if (0 != result)
+    {
+      return result;
+    }
+
+  if ((self = pthread_self ()).p == NULL)
+    {
+      return ENOMEM;
+    };
+
+  /*
+   * For self cancellation we need to ensure that a thread can't
+   * deadlock itself trying to cancel itself asynchronously
+   * (pthread_cancel is required to be an async-cancel
+   * safe function).
+   */
+  cancel_self = pthread_equal (thread, self);
+
+  tp = (ptw32_thread_t *) thread.p;
+
+  /*
+   * Lock for async-cancel safety.
+   */
+  ptw32_mcs_lock_acquire (&tp->stateLock, &stateLock);
+
+  if (tp->cancelType == PTHREAD_CANCEL_ASYNCHRONOUS
+      && tp->cancelState == PTHREAD_CANCEL_ENABLE
+      && tp->state < PThreadStateCanceling)
+    {
+      if (cancel_self)
+	{
+	  tp->state = PThreadStateCanceling;
+	  tp->cancelState = PTHREAD_CANCEL_DISABLE;
+
+	  ptw32_mcs_lock_release (&stateLock);
+	  ptw32_throw (PTW32_EPS_CANCEL);
+
+	  /* Never reached */
+	}
+      else
+	{
+	  HANDLE threadH = tp->threadH;
+
+	  SuspendThread (threadH);
+
+	  if (WaitForSingleObject (threadH, 0) == WAIT_TIMEOUT)
+	    {
+	      tp->state = PThreadStateCanceling;
+	      tp->cancelState = PTHREAD_CANCEL_DISABLE;
+	      /*
+	       * If alertdrv and QueueUserAPCEx is available then the following
+	       * will result in a call to QueueUserAPCEx with the args given, otherwise
+	       * this will result in a call to ptw32_RegisterCancelation and only
+	       * the threadH arg will be used.
+	       */
+	      ptw32_register_cancelation ((PAPCFUNC)ptw32_cancel_callback, threadH, 0);
+	      ptw32_mcs_lock_release (&stateLock);
+	      ResumeThread (threadH);
+	    }
+	}
+    }
+  else
+    {
+      /*
+       * Set for deferred cancellation.
+       */
+      if (tp->state < PThreadStateCancelPending)
+	{
+	  tp->state = PThreadStateCancelPending;
+	  if (!SetEvent (tp->cancelEvent))
+	    {
+	      result = ESRCH;
+	    }
+	}
+      else if (tp->state >= PThreadStateCanceling)
+	{
+	  result = ESRCH;
+	}
+
+      ptw32_mcs_lock_release (&stateLock);
+    }
+
+  return (result);
+}