/*
   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., 675 Mass Ave, Cambridge, MA 02139, USA.

   xrdp: A Remote Desktop Protocol server.
   Copyright (C) Jay Sorg 2004-2012

   main program

*/

#include "xrdp.h"

static struct xrdp_listen* g_listen = 0;
static long g_threadid = 0; /* main threadid */

static int g_fork_not_thread = 0;
static long g_sync_mutex = 0;
static long g_sync1_mutex = 0;
static tbus g_term_event = 0;
static tbus g_sync_event = 0;
/* syncronize stuff */
static int g_sync_command = 0;
static long g_sync_result = 0;
static long g_sync_param1 = 0;
static long g_sync_param2 = 0;
static long (*g_sync_func)(long param1, long param2);

/*****************************************************************************/
long APP_CC
g_xrdp_sync(long (*sync_func)(long param1, long param2), long sync_param1,
            long sync_param2)
{
  long sync_result;
  int sync_command;

  if (g_fork_not_thread)
  {
    /* always main thread, fork mode */
    sync_result = sync_func(sync_param1, sync_param2);
  }
  else if (tc_threadid_equal(tc_get_threadid(), g_threadid))
  {
    /* this is the main thread, call the function directly */
    sync_result = sync_func(sync_param1, sync_param2);
  }
  else
  {
    tc_mutex_lock(g_sync1_mutex);
    tc_mutex_lock(g_sync_mutex);
    g_sync_param1 = sync_param1;
    g_sync_param2 = sync_param2;
    g_sync_func = sync_func;
    g_sync_command = 100;
    tc_mutex_unlock(g_sync_mutex);
    g_set_wait_obj(g_sync_event);
    do
    {
      g_sleep(100);
      tc_mutex_lock(g_sync_mutex);
      sync_command = g_sync_command;
      sync_result = g_sync_result;
      tc_mutex_unlock(g_sync_mutex);
    }
    while (sync_command != 0);
    tc_mutex_unlock(g_sync1_mutex);
  }
  return sync_result;
}

/*****************************************************************************/
void DEFAULT_CC
xrdp_shutdown(int sig)
{
  tbus threadid;

  threadid = tc_get_threadid();
  g_writeln("shutting down");
  g_writeln("signal %d threadid %p", sig, threadid);
  if (!g_is_wait_obj_set(g_term_event))
  {
    g_set_wait_obj(g_term_event);
  }
}

/*****************************************************************************/
void DEFAULT_CC
xrdp_child(int sig)
{
  g_writeln("xrdp_child");
  g_waitchild();
}

/*****************************************************************************/
/* called in child just after fork */
int APP_CC
xrdp_child_fork(void)
{
  int pid;
  char text[256];

  /* close, don't delete these */
  g_close_wait_obj(g_term_event);
  g_close_wait_obj(g_sync_event);
  pid = g_getpid();
  g_snprintf(text, 255, "xrdp_%8.8x_main_term", pid);
  g_term_event = g_create_wait_obj(text);
  g_snprintf(text, 255, "xrdp_%8.8x_main_sync", pid);
  g_sync_event = g_create_wait_obj(text);
  return 0;
}

/*****************************************************************************/
int APP_CC
g_is_term(void)
{
  return g_is_wait_obj_set(g_term_event);
}

/*****************************************************************************/
void APP_CC
g_set_term(int in_val)
{
  if (in_val)
  {
    g_set_wait_obj(g_term_event);
  }
  else
  {
    g_reset_wait_obj(g_term_event);
  }
}

/*****************************************************************************/
tbus APP_CC
g_get_term_event(void)
{
  return g_term_event;
}

/*****************************************************************************/
tbus APP_CC
g_get_sync_event(void)
{
  return g_sync_event;
}

/*****************************************************************************/
void DEFAULT_CC
pipe_sig(int sig_num)
{
  /* do nothing */
  g_writeln("got SIGPIPE(%d)", sig_num);
}

/*****************************************************************************/
void APP_CC
g_loop(void)
{
  tc_mutex_lock(g_sync_mutex);
  if (g_sync_command != 0)
  {
    if (g_sync_func != 0)
    {
      if (g_sync_command == 100)
      {
        g_sync_result = g_sync_func(g_sync_param1, g_sync_param2);
      }
    }
    g_sync_command = 0;
  }
  tc_mutex_unlock(g_sync_mutex);
}

/*****************************************************************************/
int APP_CC
xrdp_process_params(int argc, char** argv,
                    struct xrdp_startup_params* startup_params)
{
  int index;
  char option[128];
  char value[128];

  index = 1;
  while (index < argc)
  {
    g_strncpy(option, argv[index], 127);
    if (index + 1 < argc)
    {
      g_strncpy(value, argv[index + 1], 127);
    }
    else
    {
      value[0] = 0;
    }
    if ((g_strncasecmp(option, "-help", 255)) == 0 ||
        (g_strncasecmp(option, "--help", 255)) == 0 ||
        (g_strncasecmp(option, "-h", 255)) == 0)
    {
      startup_params->help = 1;
    }
    else if ((g_strncasecmp(option, "-kill", 255) == 0) ||
             (g_strncasecmp(option, "--kill", 255) == 0) ||
             (g_strncasecmp(option, "-k", 255) == 0))
    {
      startup_params->kill = 1;
    }
    else if ((g_strncasecmp(option, "-nodaemon", 255) == 0) ||
             (g_strncasecmp(option, "--nodaemon", 255) == 0) ||
             (g_strncasecmp(option, "-nd", 255) == 0) ||
             (g_strncasecmp(option, "--nd", 255) == 0) ||
             (g_strncasecmp(option, "-ns", 255) == 0) ||
             (g_strncasecmp(option, "--ns", 255) == 0))
    {
      startup_params->no_daemon = 1;
    }
    else if ((g_strncasecmp(option, "-v", 255) == 0) ||
             (g_strncasecmp(option, "--version", 255) == 0))
    {
      startup_params->version = 1;
    }
    else if ((g_strncasecmp(option, "-p", 255) == 0) ||
             (g_strncasecmp(option, "--port", 255) == 0))
    {
      index++;
      g_strncpy(startup_params->port, value, 127);
      if (g_strlen(startup_params->port) < 1)
      {
        g_writeln("error processing params, port [%s]", startup_params->port);
        return 1;
      }
      else
      {
        g_writeln("--port parameter found, ini override [%s]",
                  startup_params->port);
      }
    }
    else if ((g_strncasecmp(option, "-f", 255) == 0) ||
             (g_strncasecmp(option, "--fork", 255) == 0))
    {
      startup_params->fork = 1;
      g_fork_not_thread = 1;
      g_writeln("running in fork mode");
    }
    else
    {
      return 1;
    }
    index++;
  }
  return 0;
}

/*****************************************************************************/
int DEFAULT_CC
main(int argc, char** argv)
{
  int test;
  int host_be;
  struct xrdp_startup_params* startup_params;
  int pid;
  int fd;
  int no_daemon;
  char text[256];
  char pid_file[256];

  g_init("xrdp");
  ssl_init();
  /* check compiled endian with actual endian */
  test = 1;
  host_be = !((int)(*(unsigned char*)(&test)));
#if defined(B_ENDIAN)
  if (!host_be)
#endif
#if defined(L_ENDIAN)
  if (host_be)
#endif
  {
    g_writeln("endian wrong, edit arch.h");
    return 0;
  }
  /* check long, int and void* sizes */
  if (sizeof(int) != 4)
  {
    g_writeln("unusable int size, must be 4");
    return 0;
  }
  if (sizeof(long) != sizeof(void*))
  {
    g_writeln("long size must match void* size");
    return 0;
  }
  if (sizeof(long) != 4 && sizeof(long) != 8)
  {
    g_writeln("unusable long size, must be 4 or 8");
    return 0;
  }
  if (sizeof(tui64) != 8)
  {
    g_writeln("unusable tui64 size, must be 8");
    return 0;
  }

  startup_params = (struct xrdp_startup_params*)
                   g_malloc(sizeof(struct xrdp_startup_params), 1);
  if (xrdp_process_params(argc, argv, startup_params) != 0)
  {
    g_writeln("Unknown Parameter");
    g_writeln("xrdp -h for help");
    g_writeln("");
    g_deinit();
    g_exit(0);
  }

  g_snprintf(pid_file, 255, "%s/xrdp.pid", XRDP_PID_PATH);
  no_daemon = 0;

  if (startup_params->kill)
  {
    g_writeln("stopping xrdp");
    /* read the xrdp.pid file */
    fd = -1;
    if (g_file_exist(pid_file)) /* xrdp.pid */
    {
      fd = g_file_open(pid_file); /* xrdp.pid */
    }
    if (fd == -1)
    {
      g_writeln("problem opening to xrdp.pid");
      g_writeln("maybe its not running");
    }
    else
    {
      g_memset(text, 0, 32);
      g_file_read(fd, text, 31);
      pid = g_atoi(text);
      g_writeln("stopping process id %d", pid);
      if (pid > 0)
      {
        g_sigterm(pid);
      }
      g_file_close(fd);
    }
    g_deinit();
    g_exit(0);
  }
  if (startup_params->no_daemon)
  {
    no_daemon = 1;
  }
  if (startup_params->help)
  {
    g_writeln("");
    g_writeln("xrdp: A Remote Desktop Protocol server.");
    g_writeln("Copyright (C) Jay Sorg 2004-2011");
    g_writeln("See http://xrdp.sourceforge.net for more information.");
    g_writeln("");
    g_writeln("Usage: xrdp [options]");
    g_writeln("   --help: show help");
    g_writeln("   --nodaemon: don't fork into background");
    g_writeln("   --kill: shut down xrdp");
    g_writeln("   --port: tcp listen port");
    g_writeln("   --fork: fork on new connection");
    g_writeln("");
    g_deinit();
    g_exit(0);
  }
  if (startup_params->version)
  {
    g_writeln("");
    g_writeln("xrdp: A Remote Desktop Protocol server.");
    g_writeln("Copyright (C) Jay Sorg 2004-2011");
    g_writeln("See http://xrdp.sourceforge.net for more information.");
    g_writeln("Version %s",PACKAGE_VERSION);
    g_writeln("");
    g_deinit();
    g_exit(0);
  }
  if (g_file_exist(pid_file)) /* xrdp.pid */
  {
    g_writeln("It looks like xrdp is allready running,");
    g_writeln("if not delete the xrdp.pid file and try again");
    g_deinit();
    g_exit(0);
  }
  if (!no_daemon)
  {
    /* make sure we can write to pid file */
    fd = g_file_open(pid_file); /* xrdp.pid */
    if (fd == -1)
    {
      g_writeln("running in daemon mode with no access to pid files, quitting");
      g_deinit();
      g_exit(0);
    }
    if (g_file_write(fd, "0", 1) == -1)
    {
      g_writeln("running in daemon mode with no access to pid files, quitting");
      g_deinit();
      g_exit(0);
    }
    g_file_close(fd);
    g_file_delete(pid_file);
  }
  if (!no_daemon)
  {
    /* start of daemonizing code */
    pid = g_fork();
    if (pid == -1)
    {
      g_writeln("problem forking");
      g_deinit();
      g_exit(1);
    }
    if (0 != pid)
    {
      g_writeln("process %d started ok", pid);
      /* exit, this is the main process */
      g_deinit();
      g_exit(0);
    }
    g_sleep(1000);
    g_file_close(0);
    g_file_close(1);
    g_file_close(2);
    g_file_open("/dev/null");
    g_file_open("/dev/null");
    g_file_open("/dev/null");
    /* end of daemonizing code */
  }
  if (!no_daemon)
  {
    /* write the pid to file */
    pid = g_getpid();
    fd = g_file_open(pid_file); /* xrdp.pid */
    if (fd == -1)
    {
      g_writeln("trying to write process id to xrdp.pid");
      g_writeln("problem opening xrdp.pid");
      g_writeln("maybe no rights");
    }
    else
    {
      g_sprintf(text, "%d", pid);
      g_file_write(fd, text, g_strlen(text));
      g_file_close(fd);
    }
  }
  g_threadid = tc_get_threadid();
  g_listen = xrdp_listen_create();
  g_signal_user_interrupt(xrdp_shutdown); /* SIGINT */
  g_signal_kill(xrdp_shutdown); /* SIGKILL */
  g_signal_pipe(pipe_sig); /* SIGPIPE */
  g_signal_terminate(xrdp_shutdown); /* SIGTERM */
  g_signal_child_stop(xrdp_child); /* SIGCHLD */
  g_sync_mutex = tc_mutex_create();
  g_sync1_mutex = tc_mutex_create();
  pid = g_getpid();
  g_snprintf(text, 255, "xrdp_%8.8x_main_term", pid);
  g_term_event = g_create_wait_obj(text);
  g_snprintf(text, 255, "xrdp_%8.8x_main_sync", pid);
  g_sync_event = g_create_wait_obj(text);
  if (g_term_event == 0)
  {
    g_writeln("error creating g_term_event");
  }
  g_listen->startup_params = startup_params;
  xrdp_listen_main_loop(g_listen);
  xrdp_listen_delete(g_listen);
  tc_mutex_delete(g_sync_mutex);
  tc_mutex_delete(g_sync1_mutex);
  g_delete_wait_obj(g_term_event);
  g_delete_wait_obj(g_sync_event);
  /* delete the xrdp.pid file */
  g_file_delete(pid_file);
  g_free(startup_params);
  g_deinit();
  return 0;
}