#include <stdio.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/msg.h>
#define MQ_KEY1 1234L
#define MQ_KEY2 2345L
#define MAXMESGDATA 4096

struct mymesg {
    long mesg_len;
    long mesg_type;
    char mesg_data[MAXMESGDATA];
};

void server(int readid, int writeid);
ssize_t mesg_send(int id, struct mymesg *mptr);
ssize_t mesg_recv(int id, struct mymesg *mptr);

int main(int argc,char **argv)
{
    int readid, writeid;
    key_t key1,key2;

    printf("Server: Hello tvk!\n");

    /*
       if((key1=ftok("/home/tvk/IPC/input.txt",'A'))<0)
       {
       printf("Server: can not get key!\n"); exit(1);
       }
       printf("key1=%x\n",key1);
   */
    if((readid=msgget(MQ_KEY1, 0666|IPC_CREAT)) < 0)
    {
        printf("Server: can not get readid!\n"); exit(1);
    }
    printf("Server: readid=%d\n",readid);
    /*	
        if((key2=ftok("/home/tvk/IPC/server_msg.c",'B'))<0)
        {
        printf("Server: can not get key!\n"); exit(1);
        }
        printf("key2=%x\n",key2);
        */
    if((writeid=msgget(MQ_KEY2, 0666|IPC_CREAT)) < 0)
    {
        printf("Server: can not get readid!\n"); exit(1);
    }
    printf("Server: writeid=%d\n",writeid);

    server(readid,writeid);

    exit(0);
}

void server(int readid, int writeid)
{
    FILE *fp;
    ssize_t n;
    struct mymesg ourmesg;

    printf("Server:readid=%d writeid=%d\n",readid,writeid);

    ourmesg.mesg_type=1;

    if( (n=mesg_recv(readid, &ourmesg)) == 0)
    {
        printf("Server: can not read file name\n");
        exit(1);	
    }
    ourmesg.mesg_data[n]='\0';

    printf("Server: file name %s\n",ourmesg.mesg_data);

    if( (fp=fopen(ourmesg.mesg_data,"r"))==NULL)
    {
        printf("Server: can not open file name\n");

    }
    else
    {
        printf("Server: %s is opened\n",ourmesg.mesg_data);

        while(fgets(ourmesg.mesg_data, MAXMESGDATA,fp) != NULL)
        { 
            ourmesg.mesg_len=strlen(ourmesg.mesg_data);
            printf("Server: %s\n",ourmesg.mesg_data);
            mesg_send(writeid,&ourmesg);
        }
    }
    fclose(fp);
    ourmesg.mesg_len=0;
    mesg_send(writeid,&ourmesg);
}

ssize_t mesg_send(int id, struct mymesg *mptr)
{
    return(msgsnd(id, &(mptr->mesg_type),mptr->mesg_len, 0));	
}

ssize_t mesg_recv(int id, struct mymesg *mptr)
{
    ssize_t n;
    n=msgrcv(id, &(mptr->mesg_type),MAXMESGDATA,mptr->mesg_type, 0);
    mptr->mesg_len=n;

    return(n);	
}