/* variables.c -- How to manipulate user visible variables in Info.   $Id: variables.c,v 1.1.1.2 1998/03/22 20:43:01 law Exp $   This file is part of GNU Info, a program for reading online documentation   stored in Info format.   Copyright (C) 1993, 97 Free Software Foundation, Inc.   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, 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.   Written by Brian Fox (bfox@ai.mit.edu). */#include "info.h"#include "variables.h"/* **************************************************************** *//*                                                                  *//*                  User Visible Variables in Info                  *//*                                                                  *//* **************************************************************** *//* Choices used by the completer when reading a zero/non-zero value for   a variable. */static char *on_off_choices[] = { "Off", "On", (char *)NULL };VARIABLE_ALIST info_variables[] = {  { "automatic-footnotes",      N_("When \"On\", footnotes appear and disappear automatically"),      &auto_footnotes_p, (char **)on_off_choices },  { "automatic-tiling",      N_("When \"On\", creating or deleting a window resizes other windows"),      &auto_tiling_p, (char **)on_off_choices },  { "visible-bell",      N_("When \"On\", flash the screen instead of ringing the bell"),      &terminal_use_visible_bell_p, (char **)on_off_choices },  { "errors-ring-bell",      N_("When \"On\", errors cause the bell to ring"),      &info_error_rings_bell_p, (char **)on_off_choices },  { "gc-compressed-files",      N_("When \"On\", Info garbage collects files which had to be uncompressed"),      &gc_compressed_files, (char **)on_off_choices },  { "show-index-match",      N_("When \"On\", the portion of the matched search string is highlighted"),      &show_index_match, (char **)on_off_choices },  { "scroll-behaviour",      N_("Controls what happens when scrolling is requested at the end of a node"),      &info_scroll_behaviour, (char **)info_scroll_choices },  { "scroll-step",      N_("The number lines to scroll when the cursor moves out of the window"),      &window_scroll_step, (char **)NULL },  { "ISO-Latin",      N_("When \"On\", Info accepts and displays ISO Latin characters"),      &ISO_Latin_p, (char **)on_off_choices },  { (char *)NULL, (char *)NULL, (int *)NULL, (char **)NULL }};DECLARE_INFO_COMMAND (describe_variable, _("Explain the use of a variable")){  VARIABLE_ALIST *var;  char *description;  /* Get the variable's name. */  var = read_variable_name (_("Describe variable: "), window);  if (!var)    return;  description = (char *)xmalloc (20 + strlen (var->name)				 + strlen (_(var->doc)));  if (var->choices)    sprintf (description, "%s (%s): %s.",             var->name, var->choices[*(var->value)], _(var->doc));  else    sprintf (description, "%s (%d): %s.",	     var->name, *(var->value), _(var->doc));  window_message_in_echo_area ("%s", description);  free (description);}DECLARE_INFO_COMMAND (set_variable, _("Set the value of an Info variable")){  VARIABLE_ALIST *var;  char *line;  /* Get the variable's name and value. */  var = read_variable_name (_("Set variable: "), window);  if (!var)    return;  /* Read a new value for this variable. */  {    char prompt[100];    if (!var->choices)      {        int potential_value;        if (info_explicit_arg || count != 1)          potential_value = count;        else          potential_value = *(var->value);        sprintf (prompt, _("Set %s to value (%d): "),                 var->name, potential_value);        line = info_read_in_echo_area (active_window, prompt);        /* If no error was printed, clear the echo area. */        if (!info_error_was_printed)          window_clear_echo_area ();        /* User aborted? */        if (!line)          return;        /* If the user specified a value, get that, otherwise, we are done. */        canonicalize_whitespace (line);        if (*line)          *(var->value) = atoi (line);        else          *(var->value) = potential_value;        free (line);      }    else      {        register int i;        REFERENCE **array = (REFERENCE **)NULL;        int array_index = 0;        int array_slots = 0;        for (i = 0; var->choices[i]; i++)          {            REFERENCE *entry;            entry = (REFERENCE *)xmalloc (sizeof (REFERENCE));            entry->label = xstrdup (var->choices[i]);            entry->nodename = (char *)NULL;            entry->filename = (char *)NULL;            add_pointer_to_array              (entry, array_index, array, array_slots, 10, REFERENCE *);          }        sprintf (prompt, _("Set %s to value (%s): "),                 var->name, var->choices[*(var->value)]);        /* Ask the completer to read a variable value for us. */        line = info_read_completing_in_echo_area (window, prompt, array);        info_free_references (array);        if (!echo_area_is_active)          window_clear_echo_area ();        /* User aborted? */        if (!line)          {            info_abort_key (active_window, 0, 0);            return;          }        /* User accepted default choice?  If so, no change. */        if (!*line)          {            free (line);            return;          }        /* Find the choice in our list of choices. */        for (i = 0; var->choices[i]; i++)          if (strcmp (var->choices[i], line) == 0)            break;        if (var->choices[i])          *(var->value) = i;      }  }}/* Read the name of an Info variable in the echo area and return the   address of a VARIABLE_ALIST member.  A return value of NULL indicates   that no variable could be read. */VARIABLE_ALIST *read_variable_name (prompt, window)     char *prompt;     WINDOW *window;{  register int i;  char *line;  REFERENCE **variables;  /* Get the completion array of variable names. */  variables = make_variable_completions_array ();  /* Ask the completer to read a variable for us. */  line =    info_read_completing_in_echo_area (window, prompt, variables);  info_free_references (variables);  if (!echo_area_is_active)    window_clear_echo_area ();  /* User aborted? */  if (!line)    {      info_abort_key (active_window, 0, 0);      return ((VARIABLE_ALIST *)NULL);    }  /* User accepted "default"?  (There is none.) */  if (!*line)    {      free (line);      return ((VARIABLE_ALIST *)NULL);    }  /* Find the variable in our list of variables. */  for (i = 0; info_variables[i].name; i++)    if (strcmp (info_variables[i].name, line) == 0)      break;  if (!info_variables[i].name)    return ((VARIABLE_ALIST *)NULL);  else    return (&(info_variables[i]));}/* Make an array of REFERENCE which actually contains the names of the   variables available in Info. */REFERENCE **make_variable_completions_array (){  register int i;  REFERENCE **array = (REFERENCE **)NULL;  int array_index = 0, array_slots = 0;  for (i = 0; info_variables[i].name; i++)    {      REFERENCE *entry;      entry = (REFERENCE *) xmalloc (sizeof (REFERENCE));      entry->label = xstrdup (info_variables[i].name);      entry->nodename = (char *)NULL;      entry->filename = (char *)NULL;      add_pointer_to_array        (entry, array_index, array, array_slots, 200, REFERENCE *);    }  return (array);}