mailbox.c

一个操作系统源代码 用于嵌入式设备 在Vc++环境下仿真 成功移植到多款处理器上

////////////////////////////////////////////////////////////////////////////////
// File Name	:       Mailbox.c
// Create Date	:       2001-6-27 pm 01:02:56
// Written by	:		CYu
// Decription	:
//------------------------------------------------------------------------------
// Copyright:   CNASIC Proprietary Material
//              Copyright (c) 2001, All Rights Reserved By:
//              National ASIC System Engineering Research Center (CNASIC) 
//				SouthEast University
//
//              DISTRIBUTION PROHIBITED without written authorization from CNASIC
//------------------------------------------------------------------------------
// Modification History
//
// 2001/10/31	by longn_qi		revise.
//
////////////////////////////////////////////////////////////////////////////////
/* System and Standard Header */
#include <sys\sysdebug.h>
#include <kernel\ros33\itron.h>
#include <kernel\ros33\ros33.h>
#define _SIZE_T_DEFINED

#include <windows.h>


/* Application Header */
#include "internal.h"

//--- macro and definition -----------------------------------------------------
//--- static variables ---------------------------------------------------------
//--- external variables -------------------------------------------------------
//--- shared variables ---------------------------------------------------------
//--- static functions ---------------------------------------------------------
//--- external functions -------------------------------------------------------

/* Function Definition */
//------------------------------------------------------------------------------
// Function name  : snd_msg
// Description    :
// Return type    : ER
// Argument       : ID mbxid
// Argument       : T_MSG*  pk_msg
// Remarks        :
// So also        :
//------------------------------------------------------------------------------
ER snd_msg( ID mbxid, T_MSG*  pk_msg )
{    
	ID idTask;

#if ENABLE_SYSCALL_STATISTIC	
	gSyscallSta[24].sta++;
#endif

    if( mbxid<=0 )
        return E_ID;

    if( mbxid>MLBX_NUM )
        return E_NOEXS;

    if( pk_msg->pNxt )
        return E_PAR;
	
	ENTER_CS

    if( aMxcb[mbxid].idTask )
    {
        idTask = aMxcb[mbxid].idTask;
        *aTcb[idTask].pMsg = pk_msg;

		aMxcb[mbxid].idTask = 0;
        aTcb[idTask].ubStatus &= ~TTS_WAI;
        aTcb[idTask].ubWaitStat &= ~TTW_MBX;

        aTcb[idTask].vwWaitRet = E_OK;

        AppendTaskToReadyQueue( idTask );

#if ENABLE_SYSMSG_STATISTIC
//		fprintf( DebugLogFile, "MailBox %d: get immediately\n", mbxid );
#endif
        
		LEAVE_CS

		ContextSwitch( );
    }
    else
    {
        if( !aMxcb[mbxid].pMsg )
            aMxcb[mbxid].pMsg = pk_msg;
        else
        {
            T_MSG*  pTemp;
            pTemp = aMxcb[mbxid].pMsg;
            while( pTemp->pNxt )
                pTemp = pTemp->pNxt;
            pTemp->pNxt = pk_msg;
        }

#if ENABLE_SYSMSG_STATISTIC
		gSysMsgSta[mbxid].cur++;
		if( gSysMsgSta[mbxid].cur > gSysMsgSta[mbxid].max )
			gSysMsgSta[mbxid].max = gSysMsgSta[mbxid].cur;
//		fprintf( DebugLogFile, "MailBox %d: len %ld, max %ld\n", mbxid, gDebugSysMsg[mbxid].cur, gDebugSysMsg[mbxid].max );
#endif

		LEAVE_CS
    }
    return E_OK;
}

//------------------------------------------------------------------------------
// Function name  : trcv_msg
// Description    : 
// Return type    : ER
// Argument       : T_MSG** ppk_msg
// Argument       : ID mbxid
// Argument       : TMO tmout
// Remarks        : 
// So also        : 
//------------------------------------------------------------------------------
ER trcv_msg( T_MSG** ppk_msg, ID mbxid, TMO tmout )
{
#if ENABLE_SYSCALL_STATISTIC	
	gSyscallSta[27].sta++;
#endif

	if( g_ubSysStat & TSS_DDSP )
        return E_CTX;

    if( mbxid<=0 )
        return E_ID;
    
    if( mbxid>MLBX_NUM )
        return E_NOEXS;
    if( tmout<=-2 )
        return E_PAR;
    
	ENTER_CS

    if( !aMxcb[mbxid].pMsg )// no message in queue
    {
        if( tmout==TMO_POL )
		{
			LEAVE_CS
            return E_TMOUT;
		}

        aTcb[idCurTask].pMsg=ppk_msg;
        aTcb[idCurTask].ubStatus |= TTS_WAI;  
        aTcb[idCurTask].ubWaitStat |= TTW_MBX;

        aMxcb[mbxid].idTask = idCurTask;
        RemoveTaskFromReadyQueue( aTcb[idCurTask].bPriority, idCurTask );
        
        if( tmout!=TMO_FEVR )
            SetTimer( hwndClient, idCurTask, tmout, ( TIMERPROC )PollingTimerHandler );
		
		LEAVE_CS

        ContextSwitch( );

		aMxcb[mbxid].idTask = 0;
		
        return aTcb[idCurTask].vwWaitRet;
    }
    else
    {
        *ppk_msg = aMxcb[mbxid].pMsg;
        aMxcb[mbxid].pMsg = aMxcb[mbxid].pMsg->pNxt;

#if ENABLE_SYSMSG_STATISTIC
		gSysMsgSta[mbxid].cur--;
//		fprintf( DebugLogFile, "MailBox %d: len %ld, max %ld\n", mbxid, gDebugSysMsg[mbxid].cur, gDebugSysMsg[mbxid].max );
#endif
		
		LEAVE_CS
    }
    return E_OK;
}
//----------------------------- The End of the File ----------------------------