sem.h

Bycore是一个嵌入式操作系统内核。Bycore包括内存管理、任务管理、中断管理、任务互斥、同步与通信管理等功能。Bycore全部由C语言完成

/**
 *  sem.h - Semaphore Mechanism.
 *
 *  Copyright (C) 2008  ZhangHu
 *  All rights reserved.
 *  E-MAIL: [e-mail]
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */


#ifndef __SEM_H__
#define __SEM_H__

#include "include/types.h"
#include "include/list.h"
#include "include/core.h"

#define SEM_BIN 0x01         /* Binary semaphore */
#define SEM_NUM 0x02         /* Counting semaphore. */
#define SEM_SYN_INIT 0x03    /* A temporary type,
                                in fact, it is Binary semaphore. */

#define SEM_OK 0x00          /* Operation is OK */
#define SEM_FALSE 0x04       /* Operation is faild. */
#define SEM_NOT_CREATE 0x05  /* Semaphore is not created. */
#define SEM_FALSE_ISR 0x06   /* Lock a semaphore in interruption context. */
#define SEM_ID_CONFLICT 0x07 /* ID confilct when create a new semaphore. */

typedef struct semaphore {
    uword_t sem_id;     /* Semaphore ID */
    word_t sem_type;    /* Semaphore type */
    word_t sem_cnt;     /* value */
    uword_t task_cnt;   /* Count all blocked task */
    slist_t tcb_link;   /* TCB links the locked semaphore with this member */
    list_t sem_link;    /* All semaphores linked by this member */
    list_t task_link[MAX_PRIO]; /* Waiting queue */
} sem_t;

/* Initialize semaphore */
void initsem(void);

/* Unlock all semaphores that a task locked */
void release_sem(tcb_t *ptcb);

/* Creating a semaphore */
sem_t *semInit(semid_t SemID,       /* The ID of new semaphore */
               uword_t InitCnt,     /* The initial count value of new semaphore */
               uword_t *err);       /* Return reasons about this operation */

/* Creating a synchronized semaphore */
sem_t *semInitSyn(semid_t SemID,    /* The ID of new semaphore */
                  uword_t *err);    /* Return reasons about this operation */

/* Creating a mutex semaphore */
sem_t *semInitMutex(semid_t SemID,  /* The ID of new semaphore */
                    uword_t *err);  /* Return reasons about this operation */

/* Get semaphore */
void semGain(semid_t SemID,         /* The ID of new semaphore */
             sem_t *pSemaphore,     /* Pointer to semaphore */
             uword_t *err);         /* Return reasons about this operation */

/* Get semaphore without block */
void semGainFree(semid_t SemID,     /* The ID of new semaphore */
                 sem_t *pSemaphore, /* Pointer to semaphore */
                 uword_t *err);     /* Return reasons about this operation */

/* Unlock a semaphore */
uword_t semPost(semid_t SemID,      /* The ID of new semaphore */
                sem_t *pSemaphore); /* Pointer to semaphore */

/* Deleting a semaphore */
void semDel(semid_t SemID,          /* The ID of new semaphore */
            sem_t *pSemaphore);     /* Pointer to semaphore */

#endif