examples/PIPS/opencproducerconsumerex/src/consumer.c

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/* INCLUDE FILES */
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <stdlib.h>

#include "CommanHeader.h"

/*****************************************************************************
*  ConsumerThreadEntryPoint
*  Function: Consumer Thread that consumes as amny as needed items when 
*  Producer has enough items produced
*  It also informs the Observer thread about item consumed
*******************************************************************************/

void* ConsumerThreadEntryPoint( void* aParam ) 
{
        ThreadParam* args = (ThreadParam*) aParam;
        int yetToConsume = args->noOfItems;
        int clientId = args->noOfConsumers;
        ProducedItem* consumeItem;
        int ret = 0;
        key_t msgQFd = -1;

        /* Construct the message to be send thru msg q */
        struct msgbuf* sendMsg = (struct msgbuf*)malloc(KMAXSENDMSG);
        sendMsg->mtype = 1;
        
        /* Get the Handler to Observer Msg Q */
        msgQFd = msgget(KMSGQKEY, IPC_CREAT);

        while (yetToConsume != 0) 
        {
                /* Acquire the Lock before checking for items available from Producer */
                sem_wait(&args->itemLock);
                /* Pop item from Producved Item-Stack */
                consumeItem = PopFromStack();
                if (consumeItem == NULL) 
                {
                        /* No items in the Stack */
                        sem_post(&args->itemLock);
                        continue;
                }
                yetToConsume--;
                /* Inform the Observer about Item Consumption */
                sprintf(&sendMsg->mtext, " Consumer#%d Consuming Produced %s\0", clientId, consumeItem->itemName);
                ret = msgsnd(msgQFd, sendMsg, strlen(sendMsg->mtext)+4, 0);

                /* Release the Lock once after getting an item */
                sem_post(&args->itemLock);
                FreeItem(consumeItem);
        }

        free( sendMsg );
        return (int*)0;
}


/*  End of File */

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