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/**
* @file
*
* @ingroup RTEMSImplClassicRegion
*
* @brief This source file contains the implementation of
* rtems_region_get_segment().
*/
/*
* COPYRIGHT (c) 1989-2007.
* On-Line Applications Research Corporation (OAR).
*
* 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.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <rtems/rtems/regionimpl.h>
#include <rtems/rtems/optionsimpl.h>
#include <rtems/rtems/statusimpl.h>
#include <rtems/score/threadqimpl.h>
#include <rtems/score/statesimpl.h>
static void _Region_Enqueue_callout(
Thread_queue_Queue *queue,
Thread_Control *the_thread,
Per_CPU_Control *cpu_self,
Thread_queue_Context *queue_context
)
{
Region_Control *the_region;
_Thread_queue_Add_timeout_ticks(
queue,
the_thread,
cpu_self,
queue_context
);
the_region = REGION_OF_THREAD_QUEUE_QUEUE( queue );
_Region_Unlock( the_region );
}
rtems_status_code rtems_region_get_segment(
rtems_id id,
uintptr_t size,
rtems_option option_set,
rtems_interval timeout,
void **segment
)
{
rtems_status_code status;
Region_Control *the_region;
if ( segment == NULL ) {
return RTEMS_INVALID_ADDRESS;
}
*segment = NULL;
if ( size == 0 ) {
return RTEMS_INVALID_SIZE;
}
the_region = _Region_Get_and_lock( id );
if ( the_region == NULL ) {
return RTEMS_INVALID_ID;
}
if ( size > the_region->maximum_segment_size ) {
status = RTEMS_INVALID_SIZE;
} else {
void *the_segment;
the_segment = _Region_Allocate_segment( the_region, size );
if ( the_segment != NULL ) {
*segment = the_segment;
status = RTEMS_SUCCESSFUL;
} else if ( _Options_Is_no_wait( option_set ) ) {
status = RTEMS_UNSATISFIED;
} else {
Thread_queue_Context queue_context;
Thread_Control *executing;
_Thread_queue_Context_initialize( &queue_context );
_Thread_queue_Acquire( &the_region->Wait_queue, &queue_context );
executing = _Thread_Executing;
executing->Wait.count = size;
executing->Wait.return_argument = segment;
/* FIXME: This is a home grown condition variable */
_Thread_queue_Context_set_thread_state(
&queue_context,
STATES_WAITING_FOR_SEGMENT
);
_Thread_queue_Context_set_timeout_ticks( &queue_context, timeout );
_Thread_queue_Context_set_enqueue_callout(
&queue_context,
_Region_Enqueue_callout
);
_Thread_queue_Enqueue(
&the_region->Wait_queue.Queue,
the_region->wait_operations,
executing,
&queue_context
);
return _Status_Get_after_wait( executing );
}
}
_Region_Unlock( the_region );
return status;
}
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