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Diffstat (limited to 'c/src/lib/libbsp/shmdr/getlq.c')
-rw-r--r--c/src/lib/libbsp/shmdr/getlq.c46
1 files changed, 46 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/shmdr/getlq.c b/c/src/lib/libbsp/shmdr/getlq.c
new file mode 100644
index 0000000000..180c33ef00
--- /dev/null
+++ b/c/src/lib/libbsp/shmdr/getlq.c
@@ -0,0 +1,46 @@
+/* Shm_Envelope_control *Shm_Locked_queue_Get( lq_cb )
+ *
+ * This routine returns an envelope control block from a shared
+ * memory queue.
+ *
+ * Input parameters:
+ * lq_cb - pointer to a locked queue control block
+ *
+ * Output parameters:
+ * returns - pointer to an envelope control block
+ * - NULL if no envelopes on specified queue
+ *
+ * COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994.
+ * On-Line Applications Research Corporation (OAR).
+ * All rights assigned to U.S. Government, 1994.
+ *
+ * This material may be reproduced by or for the U.S. Government pursuant
+ * to the copyright license under the clause at DFARS 252.227-7013. This
+ * notice must appear in all copies of this file and its derivatives.
+ *
+ * $Id$
+ */
+
+#include <rtems.h>
+#include "shm.h"
+
+Shm_Envelope_control *Shm_Locked_queue_Get(
+ Shm_Locked_queue_Control *lq_cb
+)
+{
+ Shm_Envelope_control *tmp_ecb;
+ rtems_unsigned32 tmpfront;
+
+ tmp_ecb = NULL;
+ Shm_Lock( lq_cb );
+ tmpfront = Shm_Convert(lq_cb->front);
+ if ( tmpfront != Shm_Locked_queue_End_of_list ) {
+ tmp_ecb = &Shm_Envelopes[ tmpfront ];
+ lq_cb->front = tmp_ecb->next;
+ if ( tmp_ecb->next == Shm_Locked_queue_End_of_list )
+ lq_cb->rear = Shm_Locked_queue_End_of_list;
+ tmp_ecb->next = Shm_Locked_queue_Not_on_list;
+ }
+ Shm_Unlock( lq_cb );
+ return( tmp_ecb );
+}