/*
 * Copyright notice from original mutt:
 * Copyright (C) 2000 Manoj Kasichainula <manoj@io.com>
 * Copyright (C) 2001,2005 Brendan Cully <brendan@kublai.com>
 *
 * 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 "mutt_socket.h"
#include "mutt_tunnel.h"

#include "lib/mem.h"
#include "lib/intl.h"
#include "lib/str.h"

#include <netinet/in.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <errno.h>

/* -- data types -- */
typedef struct {
  pid_t pid;
  int readfd;
  int writefd;
} TUNNEL_DATA;

/* forward declarations */
static int tunnel_socket_open (CONNECTION *);
static int tunnel_socket_close (CONNECTION *);
static int tunnel_socket_read (CONNECTION * conn, char *buf, size_t len);
static int tunnel_socket_write (CONNECTION * conn, const char *buf,
                                size_t len);

/* -- public functions -- */
int mutt_tunnel_socket_setup (CONNECTION * conn)
{
  conn->conn_open = tunnel_socket_open;
  conn->conn_close = tunnel_socket_close;
  conn->conn_read = tunnel_socket_read;
  conn->conn_write = tunnel_socket_write;

  return 0;
}

static int tunnel_socket_open (CONNECTION * conn)
{
  TUNNEL_DATA *tunnel;
  int pid;
  int rc;
  int pin[2], pout[2];

  tunnel = (TUNNEL_DATA *) mem_malloc (sizeof (TUNNEL_DATA));
  conn->sockdata = tunnel;

  mutt_message (_("Connecting with \"%s\"..."), Tunnel);

  if ((rc = pipe (pin)) == -1) {
    mutt_perror ("pipe");
    return -1;
  }
  if ((rc = pipe (pout)) == -1) {
    mutt_perror ("pipe");
    return -1;
  }

  mutt_block_signals_system ();
  if ((pid = fork ()) == 0) {
    mutt_unblock_signals_system (0);
    if (dup2 (pout[0], STDIN_FILENO) < 0 || dup2 (pin[1], STDOUT_FILENO) < 0)
      _exit (127);
    close (pin[0]);
    close (pin[1]);
    close (pout[0]);
    close (pout[1]);
    close (STDERR_FILENO);

    /* Don't let the subprocess think it can use the controlling tty */
    setsid ();

    execl (EXECSHELL, "sh", "-c", Tunnel, NULL);
    _exit (127);
  }
  mutt_unblock_signals_system (1);

  if (pid == -1) {
    close (pin[0]);
    close (pin[1]);
    close (pout[0]);
    close (pout[1]);
    mutt_perror ("fork");
    return -1;
  }
  if (close (pin[1]) < 0 || close (pout[0]) < 0)
    mutt_perror ("close");

  fcntl (pin[0], F_SETFD, FD_CLOEXEC);
  fcntl (pout[1], F_SETFD, FD_CLOEXEC);

  tunnel->readfd = pin[0];
  tunnel->writefd = pout[1];
  tunnel->pid = pid;

  conn->fd = 42;                /* stupid hack */

  return 0;
}

static int tunnel_socket_close (CONNECTION * conn)
{
  TUNNEL_DATA *tunnel = (TUNNEL_DATA *) conn->sockdata;
  int status;

  close (tunnel->readfd);
  close (tunnel->writefd);
  waitpid (tunnel->pid, &status, 0);
  if (!WIFEXITED(status) || WEXITSTATUS(status)) {
    mutt_error(_("Tunnel to %s returned error %d (%s)"),
               conn->account.host, WEXITSTATUS(status),
               NONULL(mutt_strsysexit(WEXITSTATUS(status))));
    mutt_sleep (2);
  }
  mem_free (&conn->sockdata);
  return 0;
}

static int tunnel_socket_read (CONNECTION * conn, char *buf, size_t len)
{
  TUNNEL_DATA *tunnel = (TUNNEL_DATA *) conn->sockdata;
  int rc;

  rc = read (tunnel->readfd, buf, len);
  if (rc == -1) {
    mutt_error (_("Tunnel error talking to %s: %s"), conn->account.host,
                strerror (errno));
    mutt_sleep (1);
  }

  return rc;
}

static int tunnel_socket_write (CONNECTION * conn, const char *buf,
                                size_t len)
{
  TUNNEL_DATA *tunnel = (TUNNEL_DATA *) conn->sockdata;
  int rc;

  rc = write (tunnel->writefd, buf, len);
  if (rc == -1) {
    mutt_error (_("Tunnel error talking to %s: %s"), conn->account.host,
                strerror (errno));
    mutt_sleep (1);
  }

  return rc;
}