util.c

/* vim: set ts=8 sw=4 sts=4 et: */
/*======================================================================
Copyright (C) 2008,2009,2014 OSSO B.V. <walter+rtpsniff@osso.nl>
This file is part of RTPSniff.

RTPSniff is free software: you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.

RTPSniff 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.

You should have received a copy of the GNU General Public License along
with RTPSniff.  If not, see <http://www.gnu.org/licenses/>.
======================================================================*/

#include "rtpsniff.h"
#include "endian.h"
#include <signal.h>
#include <stdio.h>

/* Includes for select(2) when usleep(3) is unavailable */
#if !(_BSD_SOURCE || _XOPEN_SOURCE >= 500)
# include <sys/time.h>
# include <sys/types.h>
# include <unistd.h>
#endif /* !(_BSD_SOURCE || _XOPEN_SOURCE >= 500) */


/* Fix non-bsd signal(2) behaviour when sigaction(2) is unavailable */
#if !(__USE_POSIX || __USE_BSD)
# ifndef _NSIG
#  define _NSIG 65
# endif
typedef void (*sighandler_t)(int);
static sighandler_t util__sighandlers[_NSIG];
void util__signal_helper(int signum) {
    util__sighandlers[signum](signum);
    if (signal(signum, util__signal_helper) == SIG_ERR)
        perror("signal");
}
#endif /* !(__USE_POSIX || __USE_BSD) */

int util_signal_set(int signum, void (*handler)(int)) {
#ifdef __USE_POSIX
    int ret;
    struct sigaction action;
    action.sa_handler = handler;
    sigemptyset(&action.sa_mask);
    action.sa_flags = 0;
    if ((ret = sigaction(signum, &action, NULL)) != 0) {
        perror("sigaction");
        return -1;
    }
#else
# ifndef __USE_BSD
    if (handler != SIG_IGN && handler != SIG_DFL) {
        assert(signum < _NSIG);
        util__sighandlers[signum] = handler;
        handler = &util__signal_helper;
    }
# endif /* !__USE_BSD */
    if (signal(signum, handler) == SIG_ERR) {
        perror("signal");
        return -1;
    }
#endif /* !__USE_POSIX && !__USE_BSD */
    return 0;
}

#if !(_BSD_SOURCE || _XOPEN_SOURCE >= 500)
int usleep(unsigned usec) {
    struct timeval timeout;
    timeout.tv_sec = usec / 1000000;
    timeout.tv_usec = usec;
    if (select(0, NULL, NULL, NULL, &timeout) == 0)
        return 0;
    return -1;
}
#endif /* !(_BSD_SOURCE || _XOPEN_SOURCE >= 500) */