Sample Subscriber

This sample code provides a simple subscriber.

/*
 * Copyright 1997 by Sun Microsystems, Inc.
 * All rights reserved
 *
 */
/*
 *
 *                            asub
 *                             --
 *                     a simple subscriber
 *                             --
 *
 * This simplistic program subscribes to events matching the
 * hard-coded event reference:
 *      enp://127.0.0.1/store
 * It subsequently received messages emitted by the apub processes
 * if any are being used, and prints the payload of each received
 * notification to stdout.
 *
 * Syntax
 *      $ asub <host> <port>
 * where
 *      <host> is the notification server hostname
 *      <port> is the notification server IP port number
 */
#include <stdlib.h>
#include <stdio.h>
#include "pasdisp.h"
#include "subscriber.h"
static pas_dispatcher_t *disp = NULL;
static subscriber_t *_subscriber = NULL;
static subscription_t *_subscription = NULL;
static renl_t *_renl = NULL;
static void _exit_usage()
{
    printf("\nUsage:\nasub host port\n");
    exit(5);
}
static void _exit_error(const char *msg)
{
    printf("%s\n", msg);
    exit(1);
}
static void _subscribe_ack(void *arg, int rc, void *subscription)
{
    (void)arg;
    if (!rc) {
        _subscription = subscription;
        printf("Subscription successful\n");
        subscriber_keepalive(_subscriber, 30000);
    }else {
        printf("Subscription failed - status %d\n", rc);
        pas_shutdown(disp);
    }
}
static void _unsubscribe_ack(void *arg, int rc, void *ignored)
{
(void *)ignored;
    (void *)arg;
    if (rc != 0) {
        printf("Unsubscribe failed - status %d\n", rc);
    }
    subscriber_delete(_subscriber);
    pas_shutdown(disp);
}
static int _handle_notify(void *arg, char *url, char *str, int len)
{
    (void *)arg;
    printf("[%s] %.*s\n", url, len, (str) ? str : "(null)");
    return 0;
}
static void _open_ack(void *arg, int rc, void *enc)
{
    _subscriber = (subscriber_t *)enc;
    (void *)arg;
    if (rc) {
        printf("Failed to create subscriber with status %d\n", rc);
        pas_shutdown(disp);
        return;
    }
    subscribe(_subscriber, "enp://127.0.0.1/store",
                _handle_notify, NULL,
                _subscribe_ack, NULL);
    return;
}
static void _unsubscribe(int sig)
{
    (int)sig;
    unsubscribe(_subscriber, _subscription, _unsubscribe_ack, NULL);
}
main(int argc, char **argv)
{
    unsigned short port = 7997;
    char host[256];
    if (argc < 2) _exit_usage();
    if (*(argv[1]) == ’0’) {
        strcpy(host, "127.0.0.1");
     }else {
        strcpy(host, argv[1]);
    }
    if (argc > 2) {
        port = (unsigned short)atoi(argv[2]);
    }    disp = pas_dispatcher_new(NULL);
    if (disp == NULL) _exit_error("Can’t create publisher");
    subscriber_new_a(disp, NULL, host, port, _open_ack, NULL);
    pas_dispatch(disp);
    pas_dispatcher_delete(disp);
exit(0);
}