Add functions for greedy workspace allocation

Various tests must check program paths that result due to failed memory
allocations from the workspace.  To avoid tinkering with internal
workspace structures throughout the test code these functions should be
used.

cpukit/rtems/Makefile.am

@@ -254,6 +254,7 @@ librtems_a_SOURCES += src/dpmemdata.c
 
 ## WORKSPACE_FILES
 librtems_a_SOURCES += src/workspace.c
+librtems_a_SOURCES += src/workspacegreedy.c
 
 librtems_a_SOURCES += src/modes.c
 

cpukit/rtems/include/rtems/rtems/support.h

@@ -101,6 +101,24 @@ bool rtems_workspace_free(
   void *pointer
 );
 
+/**
+ * @brief Greedy allocate that empties the workspace.
+ *
+ * Afterward the workspace has at most @a remaining_free_space free space left
+ * in one free block.  All other blocks are used.
+ *
+ * @see rtems_workspace_greedy_free().
+ */
+void *rtems_workspace_greedy_allocate( size_t remaining_free_space );
+
+/**
+ * @brief Frees space of a greedy allocation.
+ *
+ * The @a opaque argument must be the return value of
+ * rtems_workspace_greedy_allocate().
+ */
+void rtems_workspace_greedy_free( void *opaque );
+
 /** @} */
 
 #ifndef __RTEMS_APPLICATION__

cpukit/rtems/src/workspacegreedy.c

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2012 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Obere Lagerstr. 30
+ *  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.com/license/LICENSE.
+ */
+
+#if HAVE_CONFIG_H
+  #include "config.h"
+#endif
+
+#include <rtems/rtems/support.h>
+#include <rtems/score/wkspace.h>
+
+void *rtems_workspace_greedy_allocate( size_t remaining_free_space )
+{
+  void *opaque;
+
+  _Thread_Disable_dispatch();
+  opaque = _Heap_Greedy_allocate( &_Workspace_Area, remaining_free_space );
+  _Thread_Enable_dispatch();
+
+  return opaque;
+}
+
+void rtems_workspace_greedy_free( void *opaque )
+{
+  _Thread_Disable_dispatch();
+  _Heap_Greedy_free( &_Workspace_Area, opaque );
+  _Thread_Enable_dispatch();
+}