www.pudn.com > r&s1.10°æ±¾£«Îĵµ.rar > mailbox.c

/* 
=============================================================================== 
| Copyright (C) 2004 RuanHaiShen, All rights reserved. 
| SUMMARY:  
|   Mailbox implementation. 
| 
| DESCRIPTION: 
|   See http://www.01s.org for documentation, latest information, license  
|   and contact details. 
|   email:ruanhaishen@01s.org 
=============================================================================*/ 
/*===========================================================================*/ 
#include "arch/arch.h" 
#include "inc/queue.h" 
#include "inc/kernel.h" 
#include "inc/memory.h" 
#include "inc/ipc.h" 
#include "inc/kapi.h" 
 
 
#if CFG_MBOX_EN > 0  
err_t mbox_init(mbox_t* mbox) 
{ 
    __ASSERT(mbox != NULL); 
 
    mbox->value = 0; 
    mbox->avail = false; 
    __queue_init(mbox->tasks); 
    return EOK; 
} 
 
err_t mbox_send(mbox_t* mbox, u32 value) 
{ 
    __ASSERT(mbox != NULL); 
 
    CRITICAL_ENTER; 
    if (!mbox->avail) { 
        mbox->avail = true; 
        mbox->value = value; 
        if (__ipc_resume(&mbox->tasks) != NULL_PRIO) { 
            CRITICAL_EXIT; 
            __schedule(); 
        } else { 
            CRITICAL_EXIT; 
        } 
        return EOK; 
    } else { 
        CRITICAL_EXIT; 
        return EFULL; 
    } 
} 
 
err_t mbox_receive(mbox_t* mbox, u32* pvalue) 
{ 
    __ASSERT(mbox != NULL); 
     
#if CFG_ARG_CHK > 0 
    if (_sched_lock > 0) { 
        return ELOCK; 
    } 
#else 
    __ASSERT(_sched_lock == 0); 
#endif 
 
    while (true) { 
        CRITICAL_ENTER; 
        if (mbox->avail) { 
            mbox->avail = false; 
            *pvalue = mbox->value; 
            CRITICAL_EXIT; 
            return EOK; 
        } 
        __ipc_block(&mbox->tasks, 0); 
        CRITICAL_EXIT; 
 
        __schedule(); 
    } 
} 
 
#if CFG_IPC_TIMEOUT_EN > 0 
err_t mbox_timereceive(mbox_t* mbox, u32* pvalue, tick_t ticks) 
{ 
    register u8 current; 
 
    __ASSERT(mbox != NULL); 
  
#if CFG_ARG_CHK > 0 
    if (_sched_lock > 0) { 
        return ELOCK; 
    } 
#else 
    __ASSERT(_sched_lock == 0); 
#endif 
 
    while (true) { 
        CRITICAL_ENTER; 
        if (mbox->avail) { 
            mbox->avail = false; 
            *pvalue = mbox->value; 
            CRITICAL_EXIT; 
            return EOK; 
        } 
        __ipc_block(&mbox->tasks, ticks); 
        CRITICAL_EXIT; 
 
        __schedule(); 
 
        CRITICAL_ENTER; 
        current = _current_prio; 
        if (_tasks[current].state & STATE_BLOCKED) { 
            __ipc_timeout(&mbox->tasks); 
            CRITICAL_EXIT; 
            return ETIMEOUT; 
        } 
        __adjust_delay(current, ticks); 
        CRITICAL_EXIT; 
    } 
} 
#endif 
 
err_t mbox_flush(mbox_t* mbox) 
{ 
    __ASSERT(mbox != NULL); 
 
    CRITICAL_ENTER; 
    mbox->avail = false; 
    mbox->value = 0; 
    CRITICAL_EXIT; 
    return EOK; 
} 
 
err_t mbox_destroy(mbox_t* mbox) 
{ 
    __ASSERT(mbox != NULL); 
 
    CRITICAL_ENTER; 
    if (__ipc_resume(&mbox->tasks) != NULL_PRIO) { 
        CRITICAL_EXIT; 
        return EEXIST; 
    } 
    CRITICAL_EXIT; 
 
    return EOK; 
} 
#endif 
 
 
/*===========================================================================*/