/* core_sem.h
*
* This include file contains all the constants and structures associated
* with the Counting Semaphore Handler. A counting semaphore is the
* standard Dijkstra binary semaphore used to provide synchronization
* and mutual exclusion capabilities.
*
* 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.
*
* $Id$
*/
#ifndef __RTEMS_CORE_COUNTING_SEMAPHORE_h
#define __RTEMS_CORE_COUNTING_SEMAPHORE_h
#ifdef __cplusplus
extern "C" {
#endif
#include <rtems/score/thread.h>
#include <rtems/score/threadq.h>
#include <rtems/score/priority.h>
#include <rtems/score/watchdog.h>
/*
* The following type defines the callout which the API provides
* to support global/multiprocessor operations on semaphores.
*/
typedef void ( *CORE_semaphore_API_mp_support_callout )(
Thread_Control *,
Objects_Id
);
/*
* Blocking disciplines for a semaphore.
*/
typedef enum {
CORE_SEMAPHORE_DISCIPLINES_FIFO,
CORE_SEMAPHORE_DISCIPLINES_PRIORITY
} CORE_semaphore_Disciplines;
/*
* Core Semaphore handler return statuses.
*/
typedef enum {
CORE_SEMAPHORE_STATUS_SUCCESSFUL,
CORE_SEMAPHORE_STATUS_UNSATISFIED_NOWAIT,
CORE_SEMAPHORE_WAS_DELETED,
CORE_SEMAPHORE_TIMEOUT
} CORE_semaphore_Status;
/*
* The following defines the control block used to manage the
* attributes of each semaphore.
*/
typedef struct {
CORE_semaphore_Disciplines discipline;
} CORE_semaphore_Attributes;
/*
* The following defines the control block used to manage each
* counting semaphore.
*/
typedef struct {
Thread_queue_Control Wait_queue;
CORE_semaphore_Attributes Attributes;
unsigned32 count;
} CORE_semaphore_Control;
/*
* _CORE_semaphore_Initialize
*
* DESCRIPTION:
*
* This routine initializes the semaphore based on the parameters passed.
*/
void _CORE_semaphore_Initialize(
CORE_semaphore_Control *the_semaphore,
Objects_Classes the_class,
CORE_semaphore_Attributes *the_semaphore_attributes,
unsigned32 initial_value,
Thread_queue_Extract_callout proxy_extract_callout
);
/*
* _CORE_semaphore_Seize
*
* DESCRIPTION:
*
* This routine attempts to receive a unit from the_semaphore.
* If a unit is available or if the wait flag is FALSE, then the routine
* returns. Otherwise, the calling task is blocked until a unit becomes
* available.
*/
void _CORE_semaphore_Seize(
CORE_semaphore_Control *the_semaphore,
Objects_Id id,
boolean wait,
Watchdog_Interval timeout
);
/*
* _CORE_semaphore_Surrender
*
* DESCRIPTION:
*
* This routine frees a unit to the semaphore. If a task was blocked waiting
* for a unit from this semaphore, then that task will be readied and the unit
* given to that task. Otherwise, the unit will be returned to the semaphore.
*/
CORE_semaphore_Status _CORE_semaphore_Surrender(
CORE_semaphore_Control *the_semaphore,
Objects_Id id,
CORE_semaphore_API_mp_support_callout api_semaphore_mp_support
);
/*
* _CORE_semaphore_Flush
*
* DESCRIPTION:
*
* This routine assists in the deletion of a semaphore by flushing the
* associated wait queue.
*/
void _CORE_semaphore_Flush(
CORE_semaphore_Control *the_semaphore,
Thread_queue_Flush_callout remote_extract_callout,
unsigned32 status
);
#ifndef __RTEMS_APPLICATION__
#include <rtems/score/coresem.inl>
#endif
#ifdef __cplusplus
}
#endif
#endif
/* end of include file */
