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-rw-r--r--cpukit/posix/src/shmheap.c90
1 files changed, 90 insertions, 0 deletions
diff --git a/cpukit/posix/src/shmheap.c b/cpukit/posix/src/shmheap.c
new file mode 100644
index 0000000000..3449c15cca
--- /dev/null
+++ b/cpukit/posix/src/shmheap.c
@@ -0,0 +1,90 @@
+/**
+ * @file
+ */
+
+/*
+ * Copyright (c) 2016 Gedare Bloom.
+ *
+ * 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.
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <errno.h>
+#include <stdlib.h>
+#include <rtems/posix/shmimpl.h>
+
+int _POSIX_Shm_Object_create_from_heap(
+ POSIX_Shm_Object *shm_obj,
+ size_t size
+)
+{
+ void *p = calloc( 1, size ); /* get zero'd memory */
+ if ( p != NULL ) {
+ shm_obj->handle = p;
+ shm_obj->size = size;
+ } else {
+ errno = EIO;
+ }
+ return 0;
+}
+
+int _POSIX_Shm_Object_delete_from_heap( POSIX_Shm_Object *shm_obj )
+{
+ /* zero out memory before releasing it. */
+ memset( shm_obj->handle, 0, shm_obj->size );
+ free( shm_obj->handle );
+ shm_obj->handle = NULL;
+ shm_obj->size = 0;
+ return 0;
+}
+
+int _POSIX_Shm_Object_resize_from_heap(
+ POSIX_Shm_Object *shm_obj,
+ size_t size
+)
+{
+ void *p;
+ int err = 0;
+
+ if ( size < shm_obj->size ) {
+ /* zero out if shrinking */
+ p = (void*)((uintptr_t)shm_obj->handle + (uintptr_t)size);
+ memset( p, 0, shm_obj->size - size );
+ }
+ p = realloc( shm_obj->handle, size );
+ if ( p != NULL ) {
+ shm_obj->handle = p;
+ if ( size > shm_obj->size ) {
+ /* initialize added memory */
+ memset( p, 0, size - shm_obj->size );
+ }
+ shm_obj->size = size;
+ } else {
+ err = EIO;
+ }
+ return err;
+}
+
+int _POSIX_Shm_Object_read_from_heap(
+ POSIX_Shm_Object *shm_obj,
+ void *buf,
+ size_t count
+)
+{
+ if ( shm_obj == NULL || shm_obj->handle == NULL )
+ return 0;
+
+ if ( shm_obj->size < count ) {
+ count = shm_obj->size;
+ }
+
+ memcpy( buf, shm_obj->handle, count );
+
+ return count;
+}
+