summaryrefslogtreecommitdiff
path: root/pthread_mutex_destroy.c
diff options
context:
space:
mode:
authorrpj <rpj>2002-02-18 03:16:52 +0000
committerrpj <rpj>2002-02-18 03:16:52 +0000
commita416ab17ecf9f2cb0f1e3f7bd645a8d1ce690ca2 (patch)
tree72f776cd64e48824a5578ff7a523bc69097143b4 /pthread_mutex_destroy.c
parente6f1797e9e9925ae7f9dda54806ef8f52ae3ed07 (diff)
Major reorganisation of source code; new routine and tests added.
Diffstat (limited to 'pthread_mutex_destroy.c')
-rw-r--r--pthread_mutex_destroy.c134
1 files changed, 134 insertions, 0 deletions
diff --git a/pthread_mutex_destroy.c b/pthread_mutex_destroy.c
new file mode 100644
index 0000000..c9c1426
--- /dev/null
+++ b/pthread_mutex_destroy.c
@@ -0,0 +1,134 @@
+/*
+ * pthread_mutex_destroy.c
+ *
+ * Description:
+ * This translation unit implements mutual exclusion (mutex) primitives.
+ *
+ * --------------------------------------------------------------------------
+ *
+ * Pthreads-win32 - POSIX Threads Library for Win32
+ * Copyright(C) 1998 John E. Bossom
+ * Copyright(C) 1999,2002 Pthreads-win32 contributors
+ *
+ * Contact Email: rpj@ise.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_mutex_destroy(pthread_mutex_t *mutex)
+{
+ int result = 0;
+ pthread_mutex_t mx;
+
+ if (mutex == NULL
+ || *mutex == NULL)
+ {
+ return EINVAL;
+ }
+
+ /*
+ * Check to see if we have something to delete.
+ */
+ if (*mutex != PTHREAD_MUTEX_INITIALIZER)
+ {
+ mx = *mutex;
+
+ result = pthread_mutex_trylock(&mx);
+
+ /*
+ * The mutex type may not be RECURSIVE therefore trylock may return EBUSY if
+ * we already own the mutex. Here we are assuming that it's OK to destroy
+ * a mutex that we own and have locked recursively. Is this correct?
+ *
+ * For FAST mutexes we record the owner as ANONYMOUS for speed. In this
+ * case we assume that the thread calling pthread_mutex_destroy() is the
+ * owner, if the mutex is owned at all.
+ */
+ if (result == 0
+ || mx->ownerThread == (pthread_t) PTW32_MUTEX_OWNER_ANONYMOUS
+ || pthread_equal( mx->ownerThread, pthread_self() ) )
+ {
+ /*
+ * FIXME!!!
+ * The mutex isn't held by another thread but we could still
+ * be too late invalidating the mutex below since another thread
+ * may already have entered mutex_lock and the check for a valid
+ * *mutex != NULL.
+ */
+ *mutex = NULL;
+
+ result = pthread_mutex_unlock(&mx);
+
+ if (result == 0)
+ {
+ (void) sem_destroy( &mx->wait_sema );
+ DeleteCriticalSection( &mx->wait_cs );
+ free(mx);
+ }
+ else
+ {
+ /*
+ * Restore the mutex before we return the error.
+ */
+ *mutex = mx;
+ }
+ }
+ }
+ else
+ {
+ /*
+ * See notes in ptw32_mutex_check_need_init() above also.
+ */
+ EnterCriticalSection(&ptw32_mutex_test_init_lock);
+
+ /*
+ * Check again.
+ */
+ if (*mutex == PTHREAD_MUTEX_INITIALIZER)
+ {
+ /*
+ * This is all we need to do to destroy a statically
+ * initialised mutex that has not yet been used (initialised).
+ * If we get to here, another thread
+ * waiting to initialise this mutex will get an EINVAL.
+ */
+ *mutex = NULL;
+ }
+ else
+ {
+ /*
+ * The mutex has been initialised while we were waiting
+ * so assume it's in use.
+ */
+ result = EBUSY;
+ }
+
+ LeaveCriticalSection(&ptw32_mutex_test_init_lock);
+ }
+
+ return(result);
+}