score: Simplify CORE_message_queue_Buffer

Merge CORE_message_queue_Buffer structure into
CORE_message_queue_Buffer_control.

Use a zero-length array for the actual message buffer.  This reduces the
structure size on all targets.

Update #4007.

4 files changed, 24 insertions, 23 deletions

diff --git a/cpukit/score/src/coremsg.c b/cpukit/score/src/coremsg.c
index c86f2c28e2..f7caca1ebf 100644
--- a/cpukit/score/src/coremsg.c
+++ b/cpukit/score/src/coremsg.c
@@ -23,8 +23,13 @@
 #include <rtems/score/wkspace.h>
 
 #define MESSAGE_SIZE_LIMIT \
-  ( SIZE_MAX - sizeof( uintptr_t ) + 1 \
-    - sizeof( CORE_message_queue_Buffer_control ) )
+  ( SIZE_MAX - sizeof( uintptr_t ) + 1 - sizeof( CORE_message_queue_Buffer ) )
+
+RTEMS_STATIC_ASSERT(
+  offsetof( CORE_message_queue_Buffer, buffer )
+    == sizeof( CORE_message_queue_Buffer ),
+  CORE_MESSAGE_QUEUE_BUFFER_OFFSET
+);
 
 Status_Control _CORE_message_queue_Initialize(
   CORE_message_queue_Control     *the_message_queue,
@@ -43,8 +48,8 @@ Status_Control _CORE_message_queue_Initialize(
   buffer_size = RTEMS_ALIGN_UP( maximum_message_size, sizeof( uintptr_t ) );
   _Assert( buffer_size >= maximum_message_size );
 
-  buffer_size += sizeof( CORE_message_queue_Buffer_control );
-  _Assert( buffer_size >= sizeof( CORE_message_queue_Buffer_control ) );
+  buffer_size += sizeof( CORE_message_queue_Buffer );
+  _Assert( buffer_size >= sizeof( CORE_message_queue_Buffer ) );
 
   /* Make sure the memory allocation size computation does not overflow */
   if ( maximum_pending_messages > SIZE_MAX / buffer_size ) {
diff --git a/cpukit/score/src/coremsginsert.c b/cpukit/score/src/coremsginsert.c
index 850e1cd457..1a2abc3c96 100644
--- a/cpukit/score/src/coremsginsert.c
+++ b/cpukit/score/src/coremsginsert.c
@@ -27,11 +27,11 @@ static bool _CORE_message_queue_Order(
   const Chain_Node *right
 )
 {
-   const int                               *left_priority;
-   const CORE_message_queue_Buffer_control *right_message;
+   const int                       *left_priority;
+   const CORE_message_queue_Buffer *right_message;
 
    left_priority = (const int *) left;
-   right_message = (const CORE_message_queue_Buffer_control *) right;
+   right_message = (const CORE_message_queue_Buffer *) right;
 
    return *left_priority <
      _CORE_message_queue_Get_message_priority( right_message );
@@ -39,20 +39,20 @@ static bool _CORE_message_queue_Order(
 #endif
 
 void _CORE_message_queue_Insert_message(
-  CORE_message_queue_Control        *the_message_queue,
-  CORE_message_queue_Buffer_control *the_message,
-  const void                        *content_source,
-  size_t                             content_size,
-  CORE_message_queue_Submit_types    submit_type
+  CORE_message_queue_Control      *the_message_queue,
+  CORE_message_queue_Buffer       *the_message,
+  const void                      *content_source,
+  size_t                           content_size,
+  CORE_message_queue_Submit_types  submit_type
 )
 {
   Chain_Control *pending_messages;
 
-  the_message->Contents.size = content_size;
+  the_message->size = content_size;
 
   _CORE_message_queue_Copy_buffer(
     content_source,
-    the_message->Contents.buffer,
+    the_message->buffer,
     content_size
   );
 
diff --git a/cpukit/score/src/coremsgseize.c b/cpukit/score/src/coremsgseize.c
index bb78e28530..b2b9dbabdb 100644
--- a/cpukit/score/src/coremsgseize.c
+++ b/cpukit/score/src/coremsgseize.c
@@ -33,20 +33,16 @@ Status_Control _CORE_message_queue_Seize(
   Thread_queue_Context       *queue_context
 )
 {
-  CORE_message_queue_Buffer_control *the_message;
+  CORE_message_queue_Buffer *the_message;
 
   the_message = _CORE_message_queue_Get_pending_message( the_message_queue );
   if ( the_message != NULL ) {
     the_message_queue->number_of_pending_messages -= 1;
 
-    *size_p = the_message->Contents.size;
+    *size_p = the_message->size;
     executing->Wait.count =
       _CORE_message_queue_Get_message_priority( the_message );
-    _CORE_message_queue_Copy_buffer(
-      the_message->Contents.buffer,
-      buffer,
-      *size_p
-    );
+    _CORE_message_queue_Copy_buffer( the_message->buffer, buffer, *size_p );
 
     #if !defined(RTEMS_SCORE_COREMSG_ENABLE_BLOCKING_SEND)
       /*
diff --git a/cpukit/score/src/coremsgsubmit.c b/cpukit/score/src/coremsgsubmit.c
index dd01f4aa7a..77fe30c0dd 100644
--- a/cpukit/score/src/coremsgsubmit.c
+++ b/cpukit/score/src/coremsgsubmit.c
@@ -36,8 +36,8 @@ Status_Control _CORE_message_queue_Submit(
   Thread_queue_Context             *queue_context
 )
 {
-  CORE_message_queue_Buffer_control *the_message;
-  Thread_Control                    *the_thread;
+  CORE_message_queue_Buffer *the_message;
+  Thread_Control            *the_thread;
 
   if ( size > the_message_queue->maximum_message_size ) {
     _CORE_message_queue_Release( the_message_queue, queue_context );