/* spipe -- supervise a pipeline of programs
 * Copyright (C) 2000 Bruce Guenter <bruceg@em.ca>
 *
 * This program 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 2 of the License, 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include <errno.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <unistd.h>
#include "fork.h"
#include "bool.h"
#include "svcfns.h"

void exec_supervise(const char* dir, int fdin, int fdout)
{
  if(fdin != FD_STDIN) {
    close(FD_STDIN);
    dup2(fdin, FD_STDIN);
    close(fdin);
  }
  if(fdout != FD_STDOUT) {
    close(FD_STDOUT);
    dup2(fdout, FD_STDOUT);
    close(fdout);
  }
  execlp("supervise", "supervise", dir, 0);
  err("Could not exec supervise");
  exit(1);
}

pid_t start_supervise(const char* dir, int fdin, int fdout)
{
  pid_t pid = fork();
  switch(pid) {
  case -1:
    err("fork() failed while trying to run supervise");
    return 0;
  case 0:
    exec_supervise(dir, fdin, fdout);
  default:
    return pid;
  }
}

bool stop_supervise(const char* dir, pid_t svcpid)
{
  int status;
  pid_t pid = fork();
  if(pid == -1) {
    err("fork failed while trying to run svc");
    return false;
  }
  if(pid == 0) {
    execlp("svc", "svc", "-dx", dir, 0);
    err("exec of svc failed");
    return false;
  }
  while(waitpid(pid, &status, WUNTRACED) != pid) {
    if(errno != EINTR) {
      err("Could not wait for svc to exit");
      return false;
    }
  }
  if(!WIFEXITED(status)) {
    err("svc crashed");
    return false;
  }
  if(WEXITSTATUS(status)) {
    err("svc failed");
    return false;
  }
  while(waitpid(svcpid, &status, WUNTRACED) != svcpid)
    if(errno != EINTR) {
      err("Could not wait for supervise to exit");
      return false;
    }
  if(!WIFEXITED(status)) {
    err("supervise crashed");
    return false;
  }
  if(WEXITSTATUS(status)) {
    err("supervise failed");
    return false;
  }
  return true;
}