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/* Copyright (c) 1996-2004, Adaptec Corporation
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* - Neither the name of the Adaptec Corporation nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*File - ENGMSG.C */
/*****************************************************************************/
/* */
/*Description: */
/* This Module Contains Those Functions Functions That Allow An */
/* Application To Send The Turn Arround Type Of Messages To The */
/* DPT Engine. */
/* */
/*Author: Bob Pasteur */
/*Date: */
/* */
/*Editors: */
/* */
/*Remarks: */
/* */
/*****************************************************************************/
/*Include Files -------------------------------------------------------------*/
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include "osd_util.h"
#include "eng_std.h"
#include "rtncodes.h"
#include "messages.h"
#include "osd_unix.h"
#ifdef __cplusplus
extern "C" {
#endif
#include <sys/msg.h>
#include "lockunix.h"
#ifdef _DPT_LOGGER
#include "sem.hpp"
extern MuxEvent_C loggerThread_X;
#endif
uLONG DptEnginePid = 0;
/*-------------------------------------------------------------------------*/
/* Function MessageDPTEngine */
/*-------------------------------------------------------------------------*/
/* The Parameters Passed In To This Function Are : */
/* EngineMsgKey : Unique Engine Message Queue Identifier */
/* msqID : Engine Message Queue ID */
/* EngineMessage : Message To Be Sent To The Engine */
/* SecondsToWait : Time In Seconds To Wait Before A Timeout */
/* */
/* This Function Will Send Off A Turnarround Type Message To The Passed In */
/* Message Queue. This Function Assumes That The Alarm Signal Has Been Set */
/* Up Already By The Caller. */
/* */
/* Return : 0 For Success, Error Value Otherwise */
/*-------------------------------------------------------------------------*/
int MessageDPTEngine(int EngineMsgKey,int msqID,int EngineMessage,
int SecondsToWait)
{
MsgHdr HdrBuff;
int p_id,i,Rtnval,OldAlarm;
int Done;
Rtnval = 1;
//
// Save off the process id of this client and any old alarm value
//
p_id = (int)getpid();
OldAlarm = alarm(0);
#ifdef _DPT_LOGGER
//
// If this is the logger, we have to semaphore commands sent to the engine
// due to the threading put into the logger
//
loggerThread_X.GainAccess();
#endif
//
// Loop through until we have received the message we sent out or an
// error has occured
//
Done = 0;
while(!Done)
{
Done = 1;
//
// If there are any messages on the queue with a type of our process ID,
// they must be failed retries or some other error condition, so pull
// them off and discard them
//
i = msgrcv(msqID,(struct msgbuf *)&HdrBuff,MsgDataSize,p_id,IPC_NOWAIT);
while(i != -1)
{
i = msgrcv(msqID,(struct msgbuf *)&HdrBuff,MsgDataSize,p_id,IPC_NOWAIT);
}
//
// Set up the turnaround message, the engineTag,targetTag,and callerID are
// all set to the pid of the process
//
HdrBuff.engineTag = p_id;
HdrBuff.engEvent = EngineMessage;
HdrBuff.targetTag = p_id;
HdrBuff.callerID = p_id;
HdrBuff.BufferID = 0;
HdrBuff.FromEngBuffOffset = 0;
HdrBuff.result = 0;
// Set up the passed in message type
HdrBuff.MsgID = EngineMsgKey;
//
// Send off the message to the engine
//
if((i = (msgsnd(msqID,(struct msgbuf *)&HdrBuff,MsgDataSize,0) != -1)))
{
//
// Let's set up a little loop here receiving messages in case
// we get a "dead" message back, we will throw it away and
// continue to wait for the one we sent.
//
while(i != -1)
{
//
// Set the alarm
//
alarm(SecondsToWait);
//
// Wait for the message to come back from the engine
//
i = msgrcv(msqID,(struct msgbuf *)&HdrBuff,MsgDataSize,p_id,0);
//
// Clear thr alarm after the receive
//
alarm(0);
//
// If this is our boy, break out of the loop
//
if((i != -1)&&(HdrBuff.engEvent == EngineMessage))
{
break;
}
}
//
// If the receive returned an error, we will return the error
//
if(i == -1)
{
Rtnval = errno;
}
//
// The message returnde OK, so try to validate it
//
else {
//
// If the message type we sent is the one we got back,
// we will assume that this is the one we sent.
//
if(HdrBuff.engEvent == EngineMessage)
{
Rtnval = 0;
//
// If we havent gotten the engine's process ID yet and this
// is an open message, save off the engine pid
//
if((!DptEnginePid)&&(EngineMessage == ENGMSG_OPEN))
{
DptEnginePid = HdrBuff.callerID;
}
} //if(HdrBuff.engEvent == EngineMessage)
//
// The message we received was not the one we sent, so loop
// around and send it again
//
else {
Done = 0;
}
} //if(i == -1) else
} //if(i = msgsnd(msqID,(struct msgbuf *)&HdrBuff,MsgDataSize,0) != -1)
//else printf("\nError Sending message in MessageDPTEngine = %d",errno);
} //while(!Done)
#ifdef _DPT_LOGGER
//
// Release the logger semaphore
//
loggerThread_X.ReleaseAccess();
#endif
//
// Restore the original timmer value on the way out
//
if(OldAlarm)
{
alarm(OldAlarm);
}
return(Rtnval);
}
/*-------------------------------------------------------------------------*/
/* Function CheckForEngine */
/*-------------------------------------------------------------------------*/
/* The Parameters Passed In To This Function Are : */
/* EngineMsgKey : Unique Engine Message Queue Identifier */
/* */
/* This Function Checks For The Presence Of A Messageing Engine Of The */
/* Type That Has The Passed In Message ID. This Function Assumes That The */
/* Alarm Signal Has Been Set Up Already By The Caller. */
/* */
/* Return : Message Queue ID if Found, -1 Otherwise */
/*-------------------------------------------------------------------------*/
int CheckForEngine(int EngineMsgKey,int Clear,int SecondsToWait)
{
int msqID = -1;
struct msqid_ds CtlBuf;
int i;
int LoopCount;
MsgHdr HdrBuff;
int p_id,OldAlarm;
/* If No Timeout Is Set Up, Set It To 1 Second */
if(!SecondsToWait)
SecondsToWait = 2;
/* Try To Get The Unique Message Que Of This ID */
// need to get ENGINE's q - old code -> msqID = msgget(EngineMsgKey, ...
msqID = msgget(DPT_EngineKey, MSG_ALLRD | MSG_ALLWR);
/* If There Is One Out There, Try To Send A Message To It */
if(msqID != -1)
{
i = MessageDPTEngine(EngineMsgKey,msqID,ENGMSG_ECHO,SecondsToWait);
/* If The Message Fails, do some more checking before we fail it */
if(i)
{
/* Set Up The Header, Engine Tag == Target Tag = Caller ID = ComEngineP_ID */
/* For A Turn Around Engine Message */
p_id = (int)getpid();
HdrBuff.engineTag = p_id;
HdrBuff.engEvent = ENGMSG_ECHO;
HdrBuff.targetTag = p_id;
HdrBuff.callerID = p_id;
HdrBuff.BufferID = 0;
HdrBuff.FromEngBuffOffset = 0;
HdrBuff.result = 0;
/* Set Up The Proper Message Type In The Buffer Headers */
HdrBuff.MsgID = EngineMsgKey;
//
// Set up a loop for about a minute to wait for the echo message to
// come back if we determine that engine is out there
//
LoopCount = 60 / SecondsToWait;
while(LoopCount--)
{
//
// Is the engine locked??
//
if(IsLock("dpteng"))
{
/* Set Up The Timeout, And Save Off Any Current Timmer Value */
OldAlarm = alarm(SecondsToWait);
/* Wait For The Return Messages */
i = msgrcv(msqID,(struct msgbuf *)&HdrBuff,
MsgDataSize,p_id,0);
/* Restore The Original Timmer Value On The Way Out */
alarm(OldAlarm);
//
// If the receive fails, continue looping
//
if(i == -1)
{
continue;
}
//
// The receive was successful, so return a found status
//
else {
return(msqID);
}
}
//
// Engine isn't there, exit the loop
//
else {
break;
}
}
//
// At this point, we assume the engine is not loaded so clear
// out the message queue if they want us to
//
if(Clear)
msgctl(msqID,IPC_RMID,&CtlBuf);
msqID = -1;
}
}
return(msqID);
}
/*-------------------------------------------------------------------------*/
/* Function CheckForCommEng */
/*-------------------------------------------------------------------------*/
/* The Parameters Passed In To This Function Are : */
/* EngineMsgKey : Unique Engine Message Queue Identifier */
/* */
/* This function checks for the presence of a messaging engine of the */
/* type that has the passed in message ID. This function assumes that the */
/* alarm signal has been set up already by the caller. */
/* */
/* Return : Message Queue ID if Found, -1 Otherwise */
/*-------------------------------------------------------------------------*/
int CheckForCommEng(int EngineMsgKey,int Clear,int SecondsToWait)
{
int msqID = -1;
int i;
/* If No Timeout Is Set Up, Set It To 1 Second */
if(!SecondsToWait)
SecondsToWait = 1;
/* Try To Get The Unique Message Que Of This ID */
/* (we need to look for the ENGINE's msq) */
msqID = msgget(DPT_EngineKey, MSG_ALLRD | MSG_ALLWR);
/* If There Is One Out There, Try To Send A Message To It */
if(msqID != -1)
{
i = MessageDPTEngine(EngineMsgKey,msqID,ENGMSG_ECHO,SecondsToWait);
/* If The Message Fails, just set msgID to -1 */
/* (Since the queue belongs to the engine we can't delete it) */
if(i)
{
msqID = -1; // return -1 to indicate no other engine
}
}
return(msqID);
}
#ifdef __cplusplus
} /* extern C */
#endif
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