demo.c

/**
 * @file demo.c
 * Example fast cgi restconf server
 *
 * Copyright (C) 2019 ECLB Ltd
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this library. If not, see <http://www.gnu.org/licenses/>
 */
#include <stdio.h>
#include <stdbool.h>
#include <inttypes.h>
#include <string.h>
#include <sys/socket.h>
#include <syslog.h>
#include <glib.h>
#include <glib-unix.h>
#include "restconf.h"

#define APP_NAME                    "restconf-demo"
#define DEFAULT_APP_PID             "/var/run/"APP_NAME".pid"
#define DEFAULT_RESTCONF_SOCK       "/var/run/"APP_NAME".sock"

/* Mainloop handle */
GMainLoop *g_loop = NULL;

/* Debug */
bool debug = false;
bool verbose = false;

static gboolean termination_handler(gpointer arg1)
{
    GMainLoop *loop = (GMainLoop *) arg1;
    g_main_loop_quit(loop);
    return false;
}

void help(char *app_name)
{
    printf("Usage: %s [-h] [-b] [-d] [-v] [-m <path>] [-y <modules>] [-p <pidfile>]\n"
           "                [-n] [-l <port>] [-k <key>]\n"
           "                [-r] [-s <socket>]\n"
           "  -h   show this help\n"
           "  -b   background mode\n"
           "  -d   enable debug\n"
           "  -v   enable verbose debug\n"
           "  -m   search <path> for modules\n"
           "  -y   comma separated list of YANG modules to load (defaults to all modules in search path)\n"
           "  -p   use <pidfile> (defaults to " DEFAULT_APP_PID ")\n"
           "  -s   restconf socket <socket> (defaults to " DEFAULT_RESTCONF_SOCK ")\n",
           app_name);
}

int main(int argc, char *argv[])
{
    const char *modules = NULL;
    const char *yang = NULL;
    const char *pid_file = DEFAULT_APP_PID;
    const char *socket = DEFAULT_RESTCONF_SOCK;
    int i = 0;
    bool background = false;
    FILE *fp = NULL;

    /* Parse options */
    while ((i = getopt(argc, argv, "bdvm:y:s:p:h")) != -1) {
        switch (i) {
        case 'b':
            background = true;
            break;
        case 'd':
            debug = true;
            break;
        case 'v':
            debug = true;
            verbose = true;
            break;
        case 'm':
            modules = optarg;
            break;
        case 'y':
            yang = optarg;
            break;
        case 's':
            socket = optarg;
            break;
        case 'p':
            pid_file = optarg;
            break;
        case '?':
        case 'h':
        default:
            help(argv[0]);
            return 0;
        }
    }

    /* Daemonize */
    if (background && fork() != 0) {
        /* Parent */
        return 0;
    }

    /* Create GLib loop early */
    g_loop = g_main_loop_new(NULL, true);

    /* Create pid file */
    if (background) {
        fp = fopen(pid_file, "w");
        if (!fp) {
            printf("Failed to create PID file %s\n", pid_file);
            goto exit;
        }
        fprintf(fp, "%d\n", getpid());
        fclose(fp);
    }

    /* GLib main loop with graceful termination */
    g_unix_signal_add(SIGINT, termination_handler, g_loop);
    g_unix_signal_add(SIGTERM, termination_handler, g_loop);
    signal(SIGPIPE, SIG_IGN);
    g_main_loop_run(g_loop);

  exit:

    /* GLib main loop is done */
    g_main_loop_unref(g_loop);

    /* Remove the pid file */
    if (background)
        unlink(pid_file);

    return 0;
}