text: /****************************************************************************
   * apps/examples/chat/chat_main.c
   *
   *   Copyright (C) 2016 Vladimir Komendantskiy. All rights reserved.
   *   Author: Vladimir Komendantskiy <vladimir@moixaenergy.com>
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   * 3. Neither the name NuttX nor the names of its contributors may be
   *    used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
   * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
   * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
   * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
   * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
   * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   *
   ****************************************************************************/
  
  /****************************************************************************
   * Included Files
   ****************************************************************************/
  
  #include <nuttx/config.h>
  
  #include <sys/types.h>
  #include <sys/stat.h>
  #include <sys/ioctl.h>
  
  #include <errno.h>
  #include <fcntl.h>
  #include <poll.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <unistd.h>
  
  #include "netutils/chat.h"
  
  /****************************************************************************
   * Pre-processor Definitions
   ****************************************************************************/
  
  #define CHAT_TTYNAME_SIZE  32
  
  /****************************************************************************
   * Private Types
   ****************************************************************************/
  
  /* Chat app private state. A supertype of 'chat_ctl'. */
  
  struct chat_app
  {
    struct chat_ctl ctl;             /* Embedded 'chat_ctl' type. */
  
    /* Private fields */
  
    int argc;                        /* number of command-line arguments */
    FAR char** argv;                 /* command-line arguments */
    char tty[CHAT_TTYNAME_SIZE];     /* modem TTY device node */
    FAR char* script;                /* raw chat script - input to the parser */
    bool script_dynalloc;            /* true iff the script should be freed */
  };
  
  /****************************************************************************
   * Private Data
   ****************************************************************************/
  
  /* Preset chat scripts */
  
  FAR char g_chat_script0[] = CONFIG_EXAMPLES_CHAT_PRESET0;
  FAR char g_chat_script1[] = CONFIG_EXAMPLES_CHAT_PRESET1;
  FAR char g_chat_script2[] = CONFIG_EXAMPLES_CHAT_PRESET2;
  FAR char g_chat_script3[] = CONFIG_EXAMPLES_CHAT_PRESET3;
  
  /****************************************************************************
   * Private Functions
   ****************************************************************************/
  
  static void chat_show_usage(void)
  {
    printf("Usage: chat [options]\n"
           "  where [options] is a possibly empty list of\n"
           "-d<file>   : modem TTY device node\n"
           "-e         : echo modem output to stderr\n"
           "-f<file>   : chat script file\n"
           "-p<number> : preprogrammed script\n"
           "-t<number> : default modem response timeout\n"
           "-v         : verbose mode\n");
  }
  
  static int chat_chardev(FAR struct chat_app* priv)
  {
    int flags;
  
    flags = fcntl(priv->ctl.fd, F_GETFL, 0);
    if (flags < 0)
      {
        return flags;
      }
  
    flags = fcntl(priv->ctl.fd, F_SETFL, flags | O_NONBLOCK);
    if (flags < 0)
      {
        return flags;
      }
  
    return 0;
  }
  
  static int chat_script_preset(FAR struct chat_app* priv, int script_number)
  {
    int ret = 0;
  
    _info("preset script %d\n", script_number);
  
    switch (script_number)
      {
      case 0:
        priv->script = g_chat_script0;
        break;
  
      case 1:
        priv->script = g_chat_script1;
        break;
  
      case 2:
        priv->script = g_chat_script2;
        break;
  
      case 3:
        priv->script = g_chat_script3;
        break;
  
      default:
        ret = -ERANGE;
        break;
      }
  
    return ret;
  }
  
  static int chat_script_read(FAR struct chat_app* priv,
                              FAR const char* filepath)
  {
    FAR char* scriptp;
    size_t spare_size = CONFIG_EXAMPLES_CHAT_SIZE-1;
    ssize_t read_size;
    bool eof = false;
    int ret = 0;
    int fd;
  
    priv->script = malloc(CONFIG_EXAMPLES_CHAT_SIZE);
    if (!priv->script)
      {
        return -ENOMEM;
      }
  
    priv->script_dynalloc = true;
    scriptp = priv->script;
    memset(scriptp, 0, CONFIG_EXAMPLES_CHAT_SIZE);
  
    fd = open(filepath, O_RDONLY);
    if (fd < 0)
      {
        fprintf(stderr, "Cannot open %s, error %d\n", filepath, errno);
        ret = -ENOENT;
      }
  
    while (!ret && !eof && spare_size > 0)
      {
        read_size = read(fd, scriptp, spare_size);
        if (read_size < 0)
          {
            /* EINTR is not a read error.  It simply means that a signal was
             * received while waiting for the read to complete.
             */
  
            if (errno != EINTR)
              {
                fprintf(stderr, "Cannot read %s, error %d\n",
                        filepath, errno);
                ret = -EIO;
              }
          }
        else if (read_size == 0)
          {
            eof = true;
          }
        else
          {
            /* read_size > 0 */
  
            DEBUGASSERT(read_size <= spare_size);
            scriptp += read_size;
            spare_size -= read_size;
          }
      }
  
    close(fd);
    return ret;
  }
  
  static int chat_parse_args(FAR struct chat_app* priv)
  {
    /*
     * -d TTY device node (non-Linux feature)
     * -e echo to stderr
     * -f script file
     * -p preprogrammed script (non-Linux feature)
     * -t timeout
     * -v verbose mode
     */
  
    int numarg;
    int ret = 0;
    int i;
  
    DEBUGASSERT(priv != NULL);
  
    if (priv->argc < 2)
      {
        ret = -EINVAL;
      }
  
    /* Iterate through command-line arguments and parse those */
  
    for (i = 1; !ret && i < priv->argc && priv->argv[i]; i++)
      {
        if (priv->argv[i][0] != '-')
          {
            ret = -EINVAL;
          }
        else
          {
            switch (priv->argv[i][1])
              {
              case 'd':
                /* set the TTY device node */
  
                strncpy(priv->tty,
                        (FAR char*) priv->argv[i] + 2,
                        CHAT_TTYNAME_SIZE-1);
                break;
  
              case 'e':
                priv->ctl.echo = true;
                break;
  
              case 'f':
                ret = chat_script_read(priv,
                                       (FAR char*) priv->argv[i] + 2);
                break;
  
              case 'p':
                numarg = strtol((FAR char*) priv->argv[i] + 2,
                                NULL, 10);
                if (errno < 0)
                  {
                    ret = -EINVAL;
                    break;
                  }
  
                ret = chat_script_preset(priv, numarg);
                break;
  
              case 't':
                numarg = strtol((FAR char*) priv->argv[i] + 2,
                                NULL, 10);
  
                if (errno < 0 || numarg < 0)
                  {
                    ret = -EINVAL;
                  }
                else
                  {
                    priv->ctl.timeout = numarg;
                  }
  
                break;
  
              case 'v':
                priv->ctl.verbose = true;
                break;
  
              default:
                ret = -EINVAL;
                break;
              }
          }
      }
  
    return ret;
  }
  
  /****************************************************************************
   * Public Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: chat_main
   *
   * Description:
   *   Chat command entry point.
   *
   ****************************************************************************/
  
  #ifdef BUILD_MODULE
  int main(int argc, FAR char** argv)
  #else
  int chat_main(int argc, FAR char** argv)
  #endif
  {
    struct chat_app priv;
    int ret;
    int exit_code = EXIT_SUCCESS;
  
    priv.argc = argc;
    priv.argv = argv;
    priv.ctl.echo = false;
    priv.ctl.verbose = false;
    priv.ctl.timeout = CONFIG_EXAMPLES_CHAT_TIMEOUT_SECONDS;
    priv.script = NULL;
    priv.script_dynalloc = false;
    strncpy(priv.tty, CONFIG_EXAMPLES_CHAT_TTY_DEVNODE, CHAT_TTYNAME_SIZE-1);
  
    _info("parsing the arguments\n");
    ret = chat_parse_args((FAR struct chat_app*) &priv);
    if (ret < 0)
      {
        _info("Command line parsing failed: code %d, errno %d\n", ret, errno);
        chat_show_usage();
        exit_code = EXIT_FAILURE;
        goto with_script;
      }
  
    if (priv.script == NULL)
      {
        fprintf(stderr, "No chat script given\n");
        exit_code = EXIT_FAILURE;
        goto no_script;
      }
  
    _info("opening %s\n", priv.tty);
    priv.ctl.fd = open(priv.tty, O_RDWR);
    if (priv.ctl.fd < 0)
      {
        _info("Failed to open %s: %d\n", priv.tty, errno);
        exit_code = EXIT_FAILURE;
        goto with_script;
      }
  
    _info("setting up character device\n");
    ret = chat_chardev(&priv);
    if (ret < 0)
      {
        _info("Failed to open %s: %d\n", priv.tty, errno);
        exit_code = EXIT_FAILURE;
        goto with_tty_dev;
      }
  
    ret = chat((FAR struct chat_ctl*) &priv.ctl, priv.script);
  
  with_tty_dev:
    close(priv.ctl.fd);
  
  with_script:
    if (priv.script_dynalloc)
      {
        free(priv.script);
      }
  
  no_script:
    fflush(stderr);
    fflush(stdout);
  
    _info("Exit code %d\n", exit_code);
    return exit_code;
  }
  