freebsd/usr.sbin/procctl/procctl.c

/*
 * Copyright 1997 Sean Eric Fagan
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by Sean Eric Fagan
 * 4. Neither the name of the author may be used to endorse or promote
 *    products derived from this software without specific prior written
 *    permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 */

#ifndef lint
static const char rcsid[] =
  "$FreeBSD$";
#endif /* not lint */

/*
 * procctl -- clear the event mask, and continue, any specified processes.
 * This is largely an example of how to use the procfs interface; however,
 * for now, it is also sometimes necessary, as a stopped process will not
 * otherwise continue.  (This will be fixed in a later version of the
 * procfs code, almost certainly; however, this program will still be useful
 * for some annoying circumstances.)
 */

#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/pioctl.h>

int
main(int ac, char **av) {
  int fd;
  int i;

  for (i = 1; i < ac; i++) {
    char buf[32];

    snprintf(buf, sizeof(buf), "/proc/%s/mem", av[i]);
    fd = open(buf, O_RDWR);
    if (fd == -1) {
      if (errno == ENOENT)
	continue;
      warn("cannot open pid %s", av[i]);
      continue;
    }
    if (ioctl(fd, PIOCBIC, ~0) == -1)
      warn("cannot clear process %s's event mask", av[i]);
    if (ioctl(fd, PIOCCONT, 0) == -1 && errno != EINVAL)
      warn("cannot continue process %s", av[i]);
    close(fd);
  }
  return 0;
}