aboutsummaryrefslogtreecommitdiff
path: root/sysdeps/htl/pt-mutex-unlock.c
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/htl/pt-mutex-unlock.c')
-rw-r--r--sysdeps/htl/pt-mutex-unlock.c107
1 files changed, 107 insertions, 0 deletions
diff --git a/sysdeps/htl/pt-mutex-unlock.c b/sysdeps/htl/pt-mutex-unlock.c
new file mode 100644
index 0000000..e46a913
--- /dev/null
+++ b/sysdeps/htl/pt-mutex-unlock.c
@@ -0,0 +1,107 @@
+/* Unlock a mutex. Generic version.
+ Copyright (C) 2000-2018 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ The GNU C 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If
+ not, see <http://www.gnu.org/licenses/>. */
+
+#include <pthread.h>
+
+#include <pt-internal.h>
+
+#define LOSE do { * (int *) 0 = 0; } while (1)
+
+/* Unlock MUTEX, rescheduling a waiting thread. */
+int
+__pthread_mutex_unlock (pthread_mutex_t *mutex)
+{
+ struct __pthread *wakeup;
+ const struct __pthread_mutexattr *attr = mutex->__attr;
+
+ if (attr == __PTHREAD_ERRORCHECK_MUTEXATTR)
+ attr = &__pthread_errorcheck_mutexattr;
+ if (attr == __PTHREAD_RECURSIVE_MUTEXATTR)
+ attr = &__pthread_recursive_mutexattr;
+
+ __pthread_spin_lock (&mutex->__lock);
+
+ if (attr == NULL || attr->__mutex_type == PTHREAD_MUTEX_NORMAL)
+ {
+#if defined(ALWAYS_TRACK_MUTEX_OWNER)
+# ifndef NDEBUG
+ if (_pthread_self ())
+ {
+ assert (mutex->__owner);
+ assert (mutex->__owner == _pthread_self ());
+ mutex->__owner = NULL;
+ }
+# endif
+#endif
+ }
+ else
+ switch (attr->__mutex_type)
+ {
+ case PTHREAD_MUTEX_ERRORCHECK:
+ case PTHREAD_MUTEX_RECURSIVE:
+ if (mutex->__owner != _pthread_self ())
+ {
+ __pthread_spin_unlock (&mutex->__lock);
+ return EPERM;
+ }
+
+ if (attr->__mutex_type == PTHREAD_MUTEX_RECURSIVE)
+ if (--mutex->__locks > 0)
+ {
+ __pthread_spin_unlock (&mutex->__lock);
+ return 0;
+ }
+
+ mutex->__owner = 0;
+ break;
+
+ default:
+ LOSE;
+ }
+
+
+ if (mutex->__queue == NULL)
+ {
+ __pthread_spin_unlock (&mutex->__held);
+ __pthread_spin_unlock (&mutex->__lock);
+ return 0;
+ }
+
+ wakeup = mutex->__queue;
+ __pthread_dequeue (wakeup);
+
+#ifndef NDEBUG
+# if !defined (ALWAYS_TRACK_MUTEX_OWNER)
+ if (attr != NULL && attr->__mutex_type != PTHREAD_MUTEX_NORMAL)
+# endif
+ {
+ mutex->__owner = wakeup;
+ }
+#endif
+
+ /* We do not unlock MUTEX->held: we are transferring the ownership
+ to the thread that we are waking up. */
+
+ __pthread_spin_unlock (&mutex->__lock);
+ __pthread_wakeup (wakeup);
+
+ return 0;
+}
+
+strong_alias (__pthread_mutex_unlock, _pthread_mutex_unlock);
+strong_alias (__pthread_mutex_unlock, pthread_mutex_unlock);