/*
 * Copyright notice from original mutt:
 * Copyright (C) 1996-2000 Michael R. Elkins.
 *
 * This file is part of mutt-ng, see http://www.muttng.org/.
 * It's licensed under the GNU General Public License,
 * please see the file GPL in the top level source directory.
 */

#if HAVE_CONFIG_H
# include "config.h"
#endif

#include "mutt.h"

#include <unistd.h>
#include <stdlib.h>
#include <sys/wait.h>

/* Invokes a commmand on a pipe and optionally connects its stdin and stdout
 * to the specified handles.
 */
pid_t
mutt_create_filter_fd (const char *cmd, FILE ** in, FILE ** out, FILE ** err,
                       int fdin, int fdout, int fderr)
{
  int pin[2], pout[2], perr[2], thepid;

  if (in) {
    *in = 0;
    if (pipe (pin) == -1)
      return (-1);
  }

  if (out) {
    *out = 0;
    if (pipe (pout) == -1) {
      if (in) {
        close (pin[0]);
        close (pin[1]);
      }
      return (-1);
    }
  }

  if (err) {
    *err = 0;
    if (pipe (perr) == -1) {
      if (in) {
        close (pin[0]);
        close (pin[1]);
      }
      if (out) {
        close (pout[0]);
        close (pout[1]);
      }
      return (-1);
    }
  }

  mutt_block_signals_system ();

  if ((thepid = fork ()) == 0) {
    mutt_unblock_signals_system (0);

    if (in) {
      close (pin[1]);
      dup2 (pin[0], 0);
      close (pin[0]);
    }
    else if (fdin != -1) {
      dup2 (fdin, 0);
      close (fdin);
    }

    if (out) {
      close (pout[0]);
      dup2 (pout[1], 1);
      close (pout[1]);
    }
    else if (fdout != -1) {
      dup2 (fdout, 1);
      close (fdout);
    }

    if (err) {
      close (perr[0]);
      dup2 (perr[1], 2);
      close (perr[1]);
    }
    else if (fderr != -1) {
      dup2 (fderr, 2);
      close (fderr);
    }

    execl (EXECSHELL, "sh", "-c", cmd, NULL);
    _exit (127);
  }
  else if (thepid == -1) {
    mutt_unblock_signals_system (1);

    if (in) {
      close (pin[0]);
      close (pin[1]);
    }

    if (out) {
      close (pout[0]);
      close (pout[1]);
    }

    if (err) {
      close (perr[0]);
      close (perr[1]);
    }

    return (-1);
  }

  if (out) {
    close (pout[1]);
    *out = fdopen (pout[0], "r");
  }

  if (in) {
    close (pin[0]);
    *in = fdopen (pin[1], "w");
  }

  if (err) {
    close (perr[1]);
    *err = fdopen (perr[0], "r");
  }

  return (thepid);
}

pid_t mutt_create_filter (const char *s, FILE ** in, FILE ** out, FILE ** err)
{
  return (mutt_create_filter_fd (s, in, out, err, -1, -1, -1));
}

int mutt_wait_filter (pid_t pid)
{
  int rc;

  waitpid (pid, &rc, 0);
  mutt_unblock_signals_system (1);
  rc = WIFEXITED (rc) ? WEXITSTATUS (rc) : -1;

  return rc;
}