/*
 * @project      The CERN Tape Archive (CTA)
 * @copyright    Copyright © 2000-2022 CERN
 * @license      This program is free software, distributed under the terms of the GNU General Public
 *               Licence version 3 (GPL Version 3), copied verbatim in the file "COPYING". You can
 *               redistribute it and/or modify it under the terms of the GPL Version 3, or (at your
 *               option) any later version.
 *
 *               This program 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 General Public License for more details.
 *
 *               In applying this licence, CERN does not waive the privileges and immunities
 *               granted to it by virtue of its status as an Intergovernmental Organization or
 *               submit itself to any jurisdiction.
 */

/*
 * Cinitdaemon.c - Common routine for CASTOR daemon initialisation
 */

#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <signal.h>
#include <errno.h>
#include <osdep.h>
#include <string.h>
#include <serrno.h>

int Cinitdaemon(const char *const name,
		void (*const wait4child) (int))
{
        int c;
        int maxfds;
        struct sigaction sa;

        maxfds = getdtablesize();
        /* Background */
        if ((c = fork()) < 0) {
                fprintf (stderr, "%s: cannot fork: %s\n",name,sstrerror(errno));
                exit(1);
        } else
                if (c > 0) exit (0);
        c = setsid();
        /* Redirect standard files to /dev/null */
        if (freopen( "/dev/null", "r", stdin) == NULL) {
                fprintf (stderr, "%s: cannot freeopen stdin: %s\n",name,sstrerror(errno));
                exit(1);
        }
        if (freopen( "/dev/null", "w", stdout) == NULL) {
                fprintf (stderr, "%s: cannot freeopen stdout: %s\n",name,sstrerror(errno));
                exit(1);
        }
        if (freopen( "/dev/null", "w", stderr) == NULL) {
                fprintf (stderr, "%s: cannot freeopen stderr: %s\n",name,sstrerror(errno));
                exit(1);
        }

        for (c = 3; c < maxfds; c++)
                close (c);
        if ( wait4child != NULL ) {
                memset(&sa, 0, sizeof(sa));
                sa.sa_handler = wait4child;
                sa.sa_flags = SA_RESTART;
                sigaction (SIGCHLD, &sa, NULL);
        }
        return (maxfds);
}