/*
* CORE Message Queue Handler
*
* DESCRIPTION:
*
* This package is the implementation of the CORE Message Queue Handler.
* This core object provides task synchronization and communication functions
* via messages passed to queue objects.
*
* COPYRIGHT (c) 1989-1998.
* On-Line Applications Research Corporation (OAR).
* Copyright assigned to U.S. Government, 1994.
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.OARcorp.com/rtems/license.html.
*
* $Id$
*/
#include <rtems/system.h>
#include <rtems/score/chain.h>
#include <rtems/score/isr.h>
#include <rtems/score/object.h>
#include <rtems/score/coremsg.h>
#include <rtems/score/states.h>
#include <rtems/score/thread.h>
#include <rtems/score/wkspace.h>
#if defined(RTEMS_MULTIPROCESSING)
#include <rtems/score/mpci.h>
#endif
/*PAGE
*
* _CORE_message_queue_Initialize
*
* This routine initializes a newly created message queue based on the
* specified data.
*
* Input parameters:
* the_message_queue - the message queue to initialize
* the_class - the API specific object class
* the_message_queue_attributes - the message queue's attributes
* maximum_pending_messages - maximum message and reserved buffer count
* maximum_message_size - maximum size of each message
* proxy_extract_callout - remote extract support
*
* Output parameters:
* TRUE - if the message queue is initialized
* FALSE - if the message queue is NOT initialized
*/
boolean _CORE_message_queue_Initialize(
CORE_message_queue_Control *the_message_queue,
Objects_Classes the_class,
CORE_message_queue_Attributes *the_message_queue_attributes,
unsigned32 maximum_pending_messages,
unsigned32 maximum_message_size,
Thread_queue_Extract_callout proxy_extract_callout
)
{
unsigned32 message_buffering_required;
unsigned32 allocated_message_size;
the_message_queue->maximum_pending_messages = maximum_pending_messages;
the_message_queue->number_of_pending_messages = 0;
the_message_queue->maximum_message_size = maximum_message_size;
_CORE_message_queue_Set_notify( the_message_queue, NULL, NULL );
/*
* round size up to multiple of a ptr for chain init
*/
allocated_message_size = maximum_message_size;
if (allocated_message_size & (sizeof(unsigned32) - 1)) {
allocated_message_size += sizeof(unsigned32);
allocated_message_size &= ~(sizeof(unsigned32) - 1);
}
message_buffering_required = maximum_pending_messages *
(allocated_message_size + sizeof(CORE_message_queue_Buffer_control));
the_message_queue->message_buffers = (CORE_message_queue_Buffer *)
_Workspace_Allocate( message_buffering_required );
if (the_message_queue->message_buffers == 0)
return FALSE;
_Chain_Initialize (
&the_message_queue->Inactive_messages,
the_message_queue->message_buffers,
maximum_pending_messages,
allocated_message_size + sizeof( CORE_message_queue_Buffer_control )
);
_Chain_Initialize_empty( &the_message_queue->Pending_messages );
_Thread_queue_Initialize(
&the_message_queue->Wait_queue,
the_class,
_CORE_message_queue_Is_priority( the_message_queue_attributes ) ?
THREAD_QUEUE_DISCIPLINE_PRIORITY : THREAD_QUEUE_DISCIPLINE_FIFO,
STATES_WAITING_FOR_MESSAGE,
proxy_extract_callout,
CORE_MESSAGE_QUEUE_STATUS_TIMEOUT
);
return TRUE;
}
/*PAGE
*
* _CORE_message_queue_Close
*
* This function closes a message by returning all allocated space and
* flushing the message_queue's task wait queue.
*
* Input parameters:
* the_message_queue - the message_queue to be flushed
* remote_extract_callout - function to invoke remotely
* status - status to pass to thread
*
* Output parameters: NONE
*/
void _CORE_message_queue_Close(
CORE_message_queue_Control *the_message_queue,
Thread_queue_Flush_callout remote_extract_callout,
unsigned32 status
)
{
if ( the_message_queue->number_of_pending_messages != 0 )
(void) _CORE_message_queue_Flush_support( the_message_queue );
else
_Thread_queue_Flush(
&the_message_queue->Wait_queue,
remote_extract_callout,
status
);
(void) _Workspace_Free( the_message_queue->message_buffers );
}
/*PAGE
*
* _CORE_message_queue_Flush
*
* This function flushes the message_queue's task wait queue. The number
* of messages flushed from the queue is returned.
*
* Input parameters:
* the_message_queue - the message_queue to be flushed
*
* Output parameters:
* returns - the number of messages flushed from the queue
*/
unsigned32 _CORE_message_queue_Flush(
CORE_message_queue_Control *the_message_queue
)
{
if ( the_message_queue->number_of_pending_messages != 0 )
return _CORE_message_queue_Flush_support( the_message_queue );
else
return 0;
}
/*PAGE
*
* _CORE_message_queue_Broadcast
*
* This function sends a message for every thread waiting on the queue and
* returns the number of threads made ready by the message.
*
* Input parameters:
* the_message_queue - message is submitted to this message queue
* buffer - pointer to message buffer
* size - size in bytes of message to send
* id - id of message queue
* api_message_queue_mp_support - api specific mp support callout
* count - area to store number of threads made ready
*
* Output parameters:
* count - number of threads made ready
* CORE_MESSAGE_QUEUE_SUCCESSFUL - if successful
* error code - if unsuccessful
*/
CORE_message_queue_Status _CORE_message_queue_Broadcast(
CORE_message_queue_Control *the_message_queue,
void *buffer,
unsigned32 size,
Objects_Id id,
CORE_message_queue_API_mp_support_callout api_message_queue_mp_support,
unsigned32 *count
)
{
Thread_Control *the_thread;
unsigned32 number_broadcasted;
Thread_Wait_information *waitp;
unsigned32 constrained_size;
number_broadcasted = 0;
while ((the_thread = _Thread_queue_Dequeue(&the_message_queue->Wait_queue))) {
waitp = &the_thread->Wait;
number_broadcasted += 1;
constrained_size = size;
if ( size > the_message_queue->maximum_message_size )
constrained_size = the_message_queue->maximum_message_size;
_CORE_message_queue_Copy_buffer(
buffer,
waitp->return_argument,
constrained_size
);
*(unsigned32 *)the_thread->Wait.return_argument_1 = size;
#if defined(RTEMS_MULTIPROCESSING)
if ( !_Objects_Is_local_id( the_thread->Object.id ) )
(*api_message_queue_mp_support) ( the_thread, id );
#endif
}
*count = number_broadcasted;
return CORE_MESSAGE_QUEUE_STATUS_SUCCESSFUL;
}
/*PAGE
*
* _CORE_message_queue_Seize
*
* This kernel routine dequeues a message, copies the message buffer to
* a given destination buffer, and frees the message buffer to the
* inactive message pool. The thread will be blocked if wait is TRUE,
* otherwise an error will be given to the thread if no messages are available.
*
* Input parameters:
* the_message_queue - pointer to message queue
* id - id of object we are waitig on
* buffer - pointer to message buffer to be filled
* size - pointer to the size of buffer to be filled
* wait - TRUE if wait is allowed, FALSE otherwise
* timeout - time to wait for a message
*
* Output parameters: NONE
*
* NOTE: Dependent on BUFFER_LENGTH
*
* INTERRUPT LATENCY:
* available
* wait
*/
void _CORE_message_queue_Seize(
CORE_message_queue_Control *the_message_queue,
Objects_Id id,
void *buffer,
unsigned32 *size,
boolean wait,
Watchdog_Interval timeout
)
{
ISR_Level level;
CORE_message_queue_Buffer_control *the_message;
Thread_Control *executing;
executing = _Thread_Executing;
executing->Wait.return_code = CORE_MESSAGE_QUEUE_STATUS_SUCCESSFUL;
_ISR_Disable( level );
if ( the_message_queue->number_of_pending_messages != 0 ) {
the_message_queue->number_of_pending_messages -= 1;
the_message = _CORE_message_queue_Get_pending_message( the_message_queue );
_ISR_Enable( level );
*size = the_message->Contents.size;
_CORE_message_queue_Copy_buffer(the_message->Contents.buffer,buffer,*size );
_CORE_message_queue_Free_message_buffer(the_message_queue, the_message );
return;
}
if ( !wait ) {
_ISR_Enable( level );
executing->Wait.return_code = CORE_MESSAGE_QUEUE_STATUS_UNSATISFIED_NOWAIT;
return;
}
_Thread_queue_Enter_critical_section( &the_message_queue->Wait_queue );
executing->Wait.queue = &the_message_queue->Wait_queue;
executing->Wait.id = id;
executing->Wait.return_argument = (void *)buffer;
executing->Wait.return_argument_1 = (void *)size;
_ISR_Enable( level );
_Thread_queue_Enqueue( &the_message_queue->Wait_queue, timeout );
}
/*PAGE
*
* _CORE_message_queue_Flush_support
*
* This message handler routine removes all messages from a message queue
* and returns them to the inactive message pool. The number of messages
* flushed from the queue is returned
*
* Input parameters:
* the_message_queue - pointer to message queue
*
* Output parameters:
* returns - number of messages placed on inactive chain
*
* INTERRUPT LATENCY:
* only case
*/
unsigned32 _CORE_message_queue_Flush_support(
CORE_message_queue_Control *the_message_queue
)
{
ISR_Level level;
Chain_Node *inactive_first;
Chain_Node *message_queue_first;
Chain_Node *message_queue_last;
unsigned32 count;
_ISR_Disable( level );
inactive_first = the_message_queue->Inactive_messages.first;
message_queue_first = the_message_queue->Pending_messages.first;
message_queue_last = the_message_queue->Pending_messages.last;
the_message_queue->Inactive_messages.first = message_queue_first;
message_queue_last->next = inactive_first;
inactive_first->previous = message_queue_last;
message_queue_first->previous =
_Chain_Head( &the_message_queue->Inactive_messages );
_Chain_Initialize_empty( &the_message_queue->Pending_messages );
count = the_message_queue->number_of_pending_messages;
the_message_queue->number_of_pending_messages = 0;
_ISR_Enable( level );
return count;
}
/*PAGE
*
* _CORE_message_queue_Submit
*
* This routine implements the send and urgent message functions. It
* processes a message that is to be submitted to the designated
* message queue. The message will either be processed as a
* send message which it will be inserted at the rear of the queue
* or it will be processed as an urgent message which will be inserted
* at the front of the queue.
*
* Input parameters:
* the_message_queue - message is submitted to this message queue
* buffer - pointer to message buffer
* size - size in bytes of message to send
* id - id of message queue
* api_message_queue_mp_support - api specific mp support callout
* submit_type - send or urgent message
*
* Output parameters:
* CORE_MESSAGE_QUEUE_SUCCESSFUL - if successful
* error code - if unsuccessful
*/
CORE_message_queue_Status _CORE_message_queue_Submit(
CORE_message_queue_Control *the_message_queue,
void *buffer,
unsigned32 size,
Objects_Id id,
CORE_message_queue_API_mp_support_callout api_message_queue_mp_support,
CORE_message_queue_Submit_types submit_type
)
{
CORE_message_queue_Buffer_control *the_message;
Thread_Control *the_thread;
if ( size > the_message_queue->maximum_message_size )
return CORE_MESSAGE_QUEUE_STATUS_INVALID_SIZE;
/*
* Is there a thread currently waiting on this message queue?
*/
the_thread = _Thread_queue_Dequeue( &the_message_queue->Wait_queue );
if ( the_thread )
{
_CORE_message_queue_Copy_buffer(
buffer,
the_thread->Wait.return_argument,
size
);
*(unsigned32 *)the_thread->Wait.return_argument_1 = size;
#if defined(RTEMS_MULTIPROCESSING)
if ( !_Objects_Is_local_id( the_thread->Object.id ) )
(*api_message_queue_mp_support) ( the_thread, id );
#endif
return CORE_MESSAGE_QUEUE_STATUS_SUCCESSFUL;
}
/*
* No one waiting on this one currently.
* Allocate a message buffer and store it away
*/
if ( the_message_queue->number_of_pending_messages ==
the_message_queue->maximum_pending_messages ) {
return CORE_MESSAGE_QUEUE_STATUS_TOO_MANY;
}
the_message = _CORE_message_queue_Allocate_message_buffer(the_message_queue);
if ( the_message == 0)
return CORE_MESSAGE_QUEUE_STATUS_UNSATISFIED;
_CORE_message_queue_Copy_buffer( buffer, the_message->Contents.buffer, size );
the_message->Contents.size = size;
the_message->priority = submit_type;
the_message_queue->number_of_pending_messages += 1;
switch ( submit_type ) {
case CORE_MESSAGE_QUEUE_SEND_REQUEST:
_CORE_message_queue_Append( the_message_queue, the_message );
break;
case CORE_MESSAGE_QUEUE_URGENT_REQUEST:
_CORE_message_queue_Prepend( the_message_queue, the_message );
break;
default:
/* XXX interrupt critical section needs to be addressed */
{
CORE_message_queue_Buffer_control *this_message;
Chain_Node *the_node;
the_message->priority = submit_type;
for ( the_node = the_message_queue->Pending_messages.first ;
!_Chain_Is_tail( &the_message_queue->Pending_messages, the_node ) ;
the_node = the_node->next ) {
this_message = (CORE_message_queue_Buffer_control *) the_node;
if ( this_message->priority >= the_message->priority )
continue;
_Chain_Insert( the_node, &the_message->Node );
break;
}
}
break;
}
/*
* According to POSIX, does this happen before or after the message
* is actually enqueued. It is logical to think afterwards, because
* the message is actually in the queue at this point.
*/
if ( the_message_queue->number_of_pending_messages == 1 &&
the_message_queue->notify_handler )
(*the_message_queue->notify_handler)( the_message_queue->notify_argument );
return CORE_MESSAGE_QUEUE_STATUS_SUCCESSFUL;
}
