/**
 * xrdp: A Remote Desktop Protocol server.
 *
 * Copyright (C) Jay Sorg 2004-2013
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 *
 * @file sessvc.c
 * @brief Session supervisor
 * @author Simone Fedele
 *
 */

#if defined(HAVE_CONFIG_H)
#include "config_ac.h"
#endif
#include "file_loc.h"
#include "os_calls.h"
#include "arch.h"

static int g_term = 0;

/*****************************************************************************/
void DEFAULT_CC
term_signal_handler(int sig)
{
    g_writeln("xrdp-sessvc: term_signal_handler: got signal %d", sig);
    g_term = 1;
}

/*****************************************************************************/
void DEFAULT_CC
nil_signal_handler(int sig)
{
    g_writeln("xrdp-sessvc: nil_signal_handler: got signal %d", sig);
}

/******************************************************************************/
/* chansrv can exit at any time without cleaning up, it's an xlib app */
int APP_CC
chansrv_cleanup(int pid)
{
    char text[256];

    g_snprintf(text, 255, "/tmp/.xrdp/xrdp_chansrv_%8.8x_main_term", pid);

    if (g_file_exist(text))
    {
        g_file_delete(text);
    }

    g_snprintf(text, 255, "/tmp/.xrdp/xrdp_chansrv_%8.8x_thread_done", pid);

    if (g_file_exist(text))
    {
        g_file_delete(text);
    }

    return 0;
}

/******************************************************************************/
int DEFAULT_CC
main(int argc, char **argv)
{
    int ret = 0;
    int chansrv_pid = 0;
    int wm_pid = 0;
    int x_pid = 0;
    int lerror = 0;
    char exe_path[262];

    g_init("xrdp-sessvc");
    g_memset(exe_path, 0, sizeof(exe_path));

    if (argc < 3)
    {
        g_writeln("xrdp-sessvc: exiting, not enough parameters");
        g_deinit();
        return 1;
    }

    g_signal_terminate(term_signal_handler); /* SIGTERM */
    g_signal_user_interrupt(term_signal_handler); /* SIGINT */
    g_signal_pipe(nil_signal_handler); /* SIGPIPE */
    x_pid = g_atoi(argv[1]);
    wm_pid = g_atoi(argv[2]);
    g_writeln("xrdp-sessvc: waiting for X (pid %d) and WM (pid %d)",
              x_pid, wm_pid);
    /* run xrdp-chansrv as a separate process */
    chansrv_pid = g_fork();

    if (chansrv_pid == -1)
    {
        g_writeln("xrdp-sessvc: fork error");
        g_deinit();
        return 1;
    }
    else if (chansrv_pid == 0) /* child */
    {
        g_set_current_dir(XRDP_SBIN_PATH);
        g_snprintf(exe_path, 261, "%s/xrdp-chansrv", XRDP_SBIN_PATH);
        g_execlp3(exe_path, "xrdp-chansrv", 0);
        /* should not get here */
        g_writeln("xrdp-sessvc: g_execlp3() failed");
        g_deinit();
        return 1;
    }

    lerror = 0;
    /* wait for window manager to get done */
    ret = g_waitpid(wm_pid);

    while ((ret == 0) && !g_term)
    {
        ret = g_waitpid(wm_pid);
        g_sleep(1);
    }

    if (ret < 0)
    {
        lerror = g_get_errno();
    }

    g_writeln("xrdp-sessvc: WM is dead (waitpid said %d, errno is %d) "
              "exiting...", ret, lerror);
    /* kill channel server */
    g_writeln("xrdp-sessvc: stopping channel server");
    g_sigterm(chansrv_pid);
    ret = g_waitpid(chansrv_pid);

    while ((ret == 0) && !g_term)
    {
        ret = g_waitpid(chansrv_pid);
        g_sleep(1);
    }

    chansrv_cleanup(chansrv_pid);
    /* kill X server */
    g_writeln("xrdp-sessvc: stopping X server");
    g_sigterm(x_pid);
    ret = g_waitpid(x_pid);

    while ((ret == 0) && !g_term)
    {
        ret = g_waitpid(x_pid);
        g_sleep(1);
    }

    g_writeln("xrdp-sessvc: clean exit");
    g_deinit();
    return 0;
}