/*
 * receiver.c
 *
 * Usage: receiver
 *
 * Function: Example code to receiver a buffer of characters from a sender
 *           through a Fore ATM switch.  
 *
 * Notes:
 * 
 * The receiver must be started before the sender is started.
 *
 * The RSAP in this file must agree with the RSAP in sender.c.
 *
 */

#include <stdio.h>
#include <sys/file.h>
#include <sys/fcntl.h>

#include <fore_atm/fore_atm_user.h>

#define ATM_DEVICE "qaa0"
/* qaa[0-3], fa0 - logical devices mapping to same ATM adapter card */

#define RSAP 4096  /* receiver application service access point */
#define PBW 2000   /* peak bandwidth in kbits/sec */
#define MBW 2000   /* mean bandwidth in kbits/sec */
#define BURST 2    /* burst size in kbits */ 

#define min(a,b) (a > b ? b : a)

main(argc, argv)
    int argc;
    char **argv;
{
    int fd, qlen, mtu, i;
    int conn_id;
    u_int switchid, portid;
    Atm_info info;
    Atm_endpoint sender;
    Atm_sap rsap;
    Atm_qos qos;

    Aal_type aal = aal_type_5;  
    /* fore_xdr.h: defines aal_null, aal_type_[1-5] */
    /* XXX Are aal_type_[1,2] really supported? */

    Atm_dataflow dataflow = simplex;
    /* fore_atm_user.h: defines simplex, duplex, multicast */

    char *device_name;
    char *rbuf;


    if (argc != 1) {
        fprintf(stderr, "Usage: %s\n",argv[0]);
        exit(1);
    }

    /* Open ATM device and get file descriptor */
    device_name = malloc(strlen("/dev/") + strlen(ATM_DEVICE) + 1);
    sprintf(device_name, "/dev/%s", ATM_DEVICE);

    printf("Opening device %s.\n",device_name);
    if ((fd = atm_open(device_name, O_RDWR, &info)) < 0) {
        perror("atm_open");
        exit(1);
    }
    printf("Device opened.\n");
    mtu = min(info.mtu, 4092);    /* will break if mtu larger than 4092 */

    /* Bind ASAP to file descriptor */
    rsap = RSAP;  
    qlen = 1;
    /* atm_bind: 1 means will accept one connection request */

    printf("Binding RSAP to file descriptor.\n");
    if (atm_bind(fd, rsap, &rsap, qlen) < 0) {
        atm_error("atm_bind");
        exit(1);
    }
    printf("Binding done.  RSAP assigned %d\n",rsap);

    /* Listen for connection request */
    printf("Listening for connection request.\n");
    if (atm_listen(fd, &conn_id, &sender, &qos, &aal) < 0) {
        atm_error("atm_listen");
        exit(1);
    }
    printf("Call received.\n");

    /* use Fore macros to get switch and port id's */
    GET_SWITCH(switchid, sender.nsap);
    GET_PORT(portid, sender.nsap);
    printf("Source switch %d, port %d, sap %d, aal %d\n",
	    switchid, portid, sender.asap, aal);
    printf("Target qos of call: peak %d, mean %d, burst %d\n",
	    qos.peak_bandwidth.target, qos.mean_bandwidth.target, 
	    qos.mean_burst.target);

    /* Accept connection */
    printf("Accepting connection.\n");
    if (atm_accept(fd, fd, conn_id, &qos, dataflow) < 0) {
	atm_error("atm_accept");
	exit(1);
    } 
    printf("Connection accepted.\n");

    /* Receive data */
    rbuf = malloc(mtu);
    printf("Receiving data of size %d.\n",mtu);
    if (atm_recv(fd, rbuf, mtu) < 0) {
   	atm_error("atm_recv");
	exit(1);
    }
    printf("Data received:\n");
    for (i = 0; i < mtu; i++) 
        if (i % 100 == 0)
            printf("   index %d, value %d\n",i,rbuf[i]);


    /* Close connection - needed? */
    /* XXXX when and where to do close??  */
    /*
    printf("Closing connection.\n"); 
    atm_close(fd);
    printf("Connection closed.\n"); */

}