posix: Implement self-contained POSIX semaphores

For semaphore object pointer and object validation see
POSIX_SEMAPHORE_VALIDATE_OBJECT().

Destruction or close of a busy semaphore returns an error status.  The
object is not flushed.

POSIX semaphores are now available in all configurations and no longer
depend on --enable-posix.

Update #2514.
Update #3116.

1 files changed, 73 insertions, 0 deletions

diff --git a/cpukit/score/include/rtems/score/semaphoreimpl.h b/cpukit/score/include/rtems/score/semaphoreimpl.h
new file mode 100644
index 0000000000..a7857db93e
--- /dev/null
+++ b/cpukit/score/include/rtems/score/semaphoreimpl.h
@@ -0,0 +1,73 @@
+/*
+ * Copyright (c) 2015, 2017 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Dornierstr. 4
+ *  82178 Puchheim
+ *  Germany
+ *  <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.org/license/LICENSE.
+ */
+
+#ifndef _RTEMS_SCORE_SEMAPHOREIMPL_H
+#define _RTEMS_SCORE_SEMAPHOREIMPL_H
+
+#include <sys/lock.h>
+
+#include <rtems/score/percpu.h>
+#include <rtems/score/threadqimpl.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+typedef struct {
+  Thread_queue_Syslock_queue Queue;
+  unsigned int count;
+} Sem_Control;
+
+#define SEMAPHORE_TQ_OPERATIONS &_Thread_queue_Operations_priority
+
+static inline Sem_Control *_Sem_Get( struct _Semaphore_Control *_sem )
+{
+  return (Sem_Control *) _sem;
+}
+
+static inline Thread_Control *_Sem_Queue_acquire_critical(
+  Sem_Control          *sem,
+  Thread_queue_Context *queue_context
+)
+{
+  Thread_Control *executing;
+
+  executing = _Thread_Executing;
+  _Thread_queue_Queue_acquire_critical(
+    &sem->Queue.Queue,
+    &executing->Potpourri_stats,
+    &queue_context->Lock_context.Lock_context
+  );
+
+  return executing;
+}
+
+static inline void _Sem_Queue_release(
+  Sem_Control          *sem,
+  ISR_Level             level,
+  Thread_queue_Context *queue_context
+)
+{
+  _Thread_queue_Queue_release_critical(
+    &sem->Queue.Queue,
+    &queue_context->Lock_context.Lock_context
+  );
+  _ISR_Local_enable( level );
+}
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* _RTEMS_SCORE_SEMAPHOREIMPL_H */