infodoc.c

gcc-2.95.3 Linux下最常用的C编译器

    {
      /* If the current window is very large (greater than 45 lines),
         then split it and show the help node in another window.
         Otherwise, use the current window. */

      if (active_window->height > 45)
        active_window = window_make_window (node);
      else
        {
          set_remembered_pagetop_and_point (active_window);
          window_set_node_of_window (active_window, node);
        }

      remember_window_and_node (active_window, node);
    }
}

/* **************************************************************** */
/*                                                                  */
/*                   Groveling Info Keymaps and Docs                */
/*                                                                  */
/* **************************************************************** */

/* Return the documentation associated with the Info command FUNCTION. */
char *
function_documentation (function)
     VFunction *function;
{
  register int i;

  for (i = 0; function_doc_array[i].func; i++)
    if (function == function_doc_array[i].func)
      break;

  return (replace_in_documentation (function_doc_array[i].doc));
}

#if defined (NAMED_FUNCTIONS)
/* Return the user-visible name of the function associated with the
   Info command FUNCTION. */
char *
function_name (function)

     VFunction *function;
{
  register int i;

  for (i = 0; function_doc_array[i].func; i++)
    if (function == function_doc_array[i].func)
      break;

  return (function_doc_array[i].func_name);
}

/* Return a pointer to the function named NAME. */
VFunction *
named_function (name)
     char *name;
{
  register int i;

  for (i = 0; function_doc_array[i].func; i++)
    if (strcmp (function_doc_array[i].func_name, name) == 0)
      break;

  return (function_doc_array[i].func);
}
#endif /* NAMED_FUNCTIONS */

/* Return the documentation associated with KEY in MAP. */
char *
key_documentation (key, map)
     char key;
     Keymap map;
{
  VFunction *function = map[key].function;

  if (function)
    return (function_documentation (function));
  else
    return ((char *)NULL);
}

DECLARE_INFO_COMMAND (describe_key, _("Print documentation for KEY"))
{
  char keyname[50];
  int keyname_index = 0;
  unsigned char keystroke;
  char *rep;
  Keymap map;

  keyname[0] = '\0';
  map = window->keymap;

  while (1)
    {
      message_in_echo_area (_("Describe key: %s"), keyname);
      keystroke = info_get_input_char ();
      unmessage_in_echo_area ();

      if (Meta_p (keystroke) && (!ISO_Latin_p || key < 160))
        {
          if (map[ESC].type != ISKMAP)
            {
              window_message_in_echo_area
                (_("ESC %s is undefined."), pretty_keyname (UnMeta (keystroke)));
              return;
            }

          strcpy (keyname + keyname_index, "ESC ");
          keyname_index = strlen (keyname);
          keystroke = UnMeta (keystroke);
          map = (Keymap)map[ESC].function;
        }

      /* Add the printed representation of KEYSTROKE to our keyname. */
      rep = pretty_keyname (keystroke);
      strcpy (keyname + keyname_index, rep);
      keyname_index = strlen (keyname);

      if (map[keystroke].function == (VFunction *)NULL)
        {
          message_in_echo_area (_("%s is undefined."), keyname);
          return;
        }
      else if (map[keystroke].type == ISKMAP)
        {
          map = (Keymap)map[keystroke].function;
          strcat (keyname, " ");
          keyname_index = strlen (keyname);
          continue;
        }
      else
        {
          char *message, *fundoc, *funname = "";

#if defined (NAMED_FUNCTIONS)
          funname = function_name (map[keystroke].function);
#endif /* NAMED_FUNCTIONS */

          fundoc = function_documentation (map[keystroke].function);

          message = (char *)xmalloc
            (10 + strlen (keyname) + strlen (fundoc) + strlen (funname));

#if defined (NAMED_FUNCTIONS)
          sprintf (message, "%s (%s): %s.", keyname, funname, fundoc);
#else
          sprintf (message, _("%s is defined to %s."), keyname, fundoc);
#endif /* !NAMED_FUNCTIONS */

          window_message_in_echo_area ("%s", message);
          free (message);
          break;
        }
    }
}

/* How to get the pretty printable name of a character. */
static char rep_buffer[30];

char *
pretty_keyname (key)
     unsigned char key;
{
  char *rep;

  if (Meta_p (key))
    {
      char temp[20];

      rep = pretty_keyname (UnMeta (key));

      sprintf (temp, "ESC %s", rep);
      strcpy (rep_buffer, temp);
      rep = rep_buffer;
    }
  else if (Control_p (key))
    {
      switch (key)
        {
        case '\n': rep = "LFD"; break;
        case '\t': rep = "TAB"; break;
        case '\r': rep = "RET"; break;
        case ESC:  rep = "ESC"; break;

        default:
          sprintf (rep_buffer, "C-%c", UnControl (key));
          rep = rep_buffer;
        }
    }
  else
    {
      switch (key)
        {
        case ' ': rep = "SPC"; break;
        case DEL: rep = "DEL"; break;
        default:
          rep_buffer[0] = key;
          rep_buffer[1] = '\0';
          rep = rep_buffer;
        }
    }
  return (rep);
}

/* Replace the names of functions with the key that invokes them. */
char *
replace_in_documentation (string)
     char *string;
{
  register int i, start, next;
  static char *result = (char *)NULL;

  maybe_free (result);
  result = (char *)xmalloc (1 + strlen (string));

  i = next = start = 0;

  /* Skip to the beginning of a replaceable function. */
  for (i = start; string[i]; i++)
    {
      /* Is this the start of a replaceable function name? */
      if (string[i] == '\\' && string[i + 1] == '[')
        {
          char *fun_name, *rep;
          VFunction *function;

          /* Copy in the old text. */
          strncpy (result + next, string + start, i - start);
          next += (i - start);
          start = i + 2;

          /* Move to the end of the function name. */
          for (i = start; string[i] && (string[i] != ']'); i++);

          fun_name = (char *)xmalloc (1 + i - start);
          strncpy (fun_name, string + start, i - start);
          fun_name[i - start] = '\0';

          /* Find a key which invokes this function in the info_keymap. */
          function = named_function (fun_name);

          /* If the internal documentation string fails, there is a 
             serious problem with the associated command's documentation.
             We croak so that it can be fixed immediately. */
          if (!function)
            abort ();

          rep = where_is (info_keymap, function);
          strcpy (result + next, rep);
          next = strlen (result);

          start = i;
          if (string[i])
            start++;
        }
    }
  strcpy (result + next, string + start);
  return (result);
}

/* Return a string of characters which could be typed from the keymap
   MAP to invoke FUNCTION. */
static char *where_is_rep = (char *)NULL;
static int where_is_rep_index = 0;
static int where_is_rep_size = 0;

static char *
where_is (map, function)
     Keymap map;
     VFunction *function;
{
  char *rep;

  if (!where_is_rep_size)
    where_is_rep = (char *)xmalloc (where_is_rep_size = 100);
  where_is_rep_index = 0;

  rep = where_is_internal (map, function);

  /* If it couldn't be found, return "M-x Foo". */
  if (!rep)
    {
      char *name;

      name = function_name (function);

      if (name)
        sprintf (where_is_rep, "M-x %s", name);

      rep = where_is_rep;
    }
  return (rep);
}

/* Return the printed rep of FUNCTION as found in MAP, or NULL. */
static char *
where_is_internal (map, function)
     Keymap map;
     VFunction *function;
{
  register int i;
  
  /* If the function is directly invokable in MAP, return the representation
     of that keystroke. */
  for (i = 0; i < 256; i++)
    if ((map[i].type == ISFUNC) && map[i].function == function)
      {
        sprintf (where_is_rep + where_is_rep_index, "%s", pretty_keyname (i));
        return (where_is_rep);
      }

  /* Okay, search subsequent maps for this function. */
  for (i = 0; i < 256; i++)
    {
      if (map[i].type == ISKMAP)
        {
          int saved_index = where_is_rep_index;
          char *rep;

          sprintf (where_is_rep + where_is_rep_index, "%s ",
                   pretty_keyname (i));

          where_is_rep_index = strlen (where_is_rep);
          rep = where_is_internal ((Keymap)map[i].function, function);

          if (rep)
            return (where_is_rep);

          where_is_rep_index = saved_index;
        }
    }

  return ((char *)NULL);
}

extern char *read_function_name ();

DECLARE_INFO_COMMAND (info_where_is,
   "Show what to type to execute a given command")
{
  char *command_name;

  command_name = read_function_name (_("Where is command: "), window);

  if (!command_name)
    {
      info_abort_key (active_window, count, key);
      return;
    }

  if (*command_name)
    {
      VFunction *function;

      function = named_function (command_name);

      if (function)
        {
          char *location;

          location = where_is (active_window->keymap, function);

          if (!location)
            {
              info_error (_("`%s' is not on any keys"), command_name);
            }
          else
            {
              if (strncmp (location, "M-x ", 4) == 0)
                window_message_in_echo_area
                  (_("%s can only be invoked via %s."), command_name, location);
              else
                window_message_in_echo_area
                  (_("%s can be invoked via %s."), command_name, location);
            }
        }
      else
        info_error (_("There is no function named `%s'"), command_name);
    }

  free (command_name);
}