gnu/dist/texinfo/info/variables.c

   1 /*      $NetBSD$        */
   2
   3 /* variables.c -- how to manipulate user visible variables in Info.
   4    Id: variables.c,v 1.3 2004/04/11 17:56:46 karl Exp
   5
   6    Copyright (C) 1993, 1997, 2001, 2002, 2004 Free Software Foundation, Inc.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2, or (at your option)
  11    any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  21
  22    Written by Brian Fox (bfox@ai.mit.edu). */
  23
  24 #include "info.h"
  25 #include "variables.h"
  26
  27 /* **************************************************************** */
  28 /*                                                                  */
  29 /*                  User Visible Variables in Info                  */
  30 /*                                                                  */
  31 /* **************************************************************** */
  32
  33 /* Choices used by the completer when reading a zero/non-zero value for
  34    a variable. */
  35 static char *on_off_choices[] = { "Off", "On", (char *)NULL };
  36
  37 VARIABLE_ALIST info_variables[] = {
  38   { "automatic-footnotes",
  39       N_("When \"On\", footnotes appear and disappear automatically"),
  40       &auto_footnotes_p, (char **)on_off_choices },
  41
  42   { "automatic-tiling",
  43       N_("When \"On\", creating or deleting a window resizes other windows"),
  44       &auto_tiling_p, (char **)on_off_choices },
  45
  46   { "visible-bell",
  47       N_("When \"On\", flash the screen instead of ringing the bell"),
  48       &terminal_use_visible_bell_p, (char **)on_off_choices },
  49
  50   { "errors-ring-bell",
  51       N_("When \"On\", errors cause the bell to ring"),
  52       &info_error_rings_bell_p, (char **)on_off_choices },
  53
  54   { "gc-compressed-files",
  55       N_("When \"On\", Info garbage collects files which had to be uncompressed"),
  56       &gc_compressed_files, (char **)on_off_choices },
  57   { "show-index-match",
  58       N_("When \"On\", the portion of the matched search string is highlighted"),
  59       &show_index_match, (char **)on_off_choices },
  60
  61   { "scroll-behaviour",
  62       N_("Controls what happens when scrolling is requested at the end of a node"),
  63       &info_scroll_behaviour, (char **)info_scroll_choices },
  64
  65   { "scroll-step",
  66       N_("The number lines to scroll when the cursor moves out of the window"),
  67       &window_scroll_step, (char **)NULL },
  68
  69   { "ISO-Latin",
  70       N_("When \"On\", Info accepts and displays ISO Latin characters"),
  71       &ISO_Latin_p, (char **)on_off_choices },
  72
  73   { (char *)NULL, (char *)NULL, (int *)NULL, (char **)NULL }
  74 };
  75
  76 DECLARE_INFO_COMMAND (describe_variable, _("Explain the use of a variable"))
  77 {
  78   VARIABLE_ALIST *var;
  79   char *description;
  80
  81   /* Get the variable's name. */
  82   var = read_variable_name ((char *) _("Describe variable: "), window);
  83
  84   if (!var)
  85     return;
  86
  87   description = (char *)xmalloc (20 + strlen (var->name)
  88                                  + strlen (_(var->doc)));
  89
  90   if (var->choices)
  91     sprintf (description, "%s (%s): %s.",
  92              var->name, var->choices[*(var->value)], _(var->doc));
  93   else
  94     sprintf (description, "%s (%d): %s.",
  95              var->name, *(var->value), _(var->doc));
  96
  97   window_message_in_echo_area ("%s", description, NULL);
  98   free (description);
  99 }
 100
 101 DECLARE_INFO_COMMAND (set_variable, _("Set the value of an Info variable"))
 102 {
 103   VARIABLE_ALIST *var;
 104   char *line;
 105
 106   /* Get the variable's name and value. */
 107   var = read_variable_name ((char *) _("Set variable: "), window);
 108
 109   if (!var)
 110     return;
 111
 112   /* Read a new value for this variable. */
 113   {
 114     char prompt[100];
 115
 116     if (!var->choices)
 117       {
 118         int potential_value;
 119
 120         if (info_explicit_arg || count != 1)
 121           potential_value = count;
 122         else
 123           potential_value = *(var->value);
 124
 125         sprintf (prompt, _("Set %s to value (%d): "),
 126                  var->name, potential_value);
 127         line = info_read_in_echo_area (active_window, prompt);
 128
 129         /* If no error was printed, clear the echo area. */
 130         if (!info_error_was_printed)
 131           window_clear_echo_area ();
 132
 133         /* User aborted? */
 134         if (!line)
 135           return;
 136
 137         /* If the user specified a value, get that, otherwise, we are done. */
 138         canonicalize_whitespace (line);
 139         if (*line)
 140           *(var->value) = atoi (line);
 141         else
 142           *(var->value) = potential_value;
 143
 144         free (line);
 145       }
 146     else
 147       {
 148         register int i;
 149         REFERENCE **array = (REFERENCE **)NULL;
 150         int array_index = 0;
 151         int array_slots = 0;
 152
 153         for (i = 0; var->choices[i]; i++)
 154           {
 155             REFERENCE *entry;
 156
 157             entry = (REFERENCE *)xmalloc (sizeof (REFERENCE));
 158             entry->label = xstrdup (var->choices[i]);
 159             entry->nodename = (char *)NULL;
 160             entry->filename = (char *)NULL;
 161
 162             add_pointer_to_array
 163               (entry, array_index, array, array_slots, 10, REFERENCE *);
 164           }
 165
 166         sprintf (prompt, _("Set %s to value (%s): "),
 167                  var->name, var->choices[*(var->value)]);
 168
 169         /* Ask the completer to read a variable value for us. */
 170         line = info_read_completing_in_echo_area (window, prompt, array);
 171
 172         info_free_references (array);
 173
 174         if (!echo_area_is_active)
 175           window_clear_echo_area ();
 176
 177         /* User aborted? */
 178         if (!line)
 179           {
 180             info_abort_key (active_window, 0, 0);
 181             return;
 182           }
 183
 184         /* User accepted default choice?  If so, no change. */
 185         if (!*line)
 186           {
 187             free (line);
 188             return;
 189           }
 190
 191         /* Find the choice in our list of choices. */
 192         for (i = 0; var->choices[i]; i++)
 193           if (strcmp (var->choices[i], line) == 0)
 194             break;
 195
 196         if (var->choices[i])
 197           *(var->value) = i;
 198       }
 199   }
 200 }
 201
 202 /* Read the name of an Info variable in the echo area and return the
 203    address of a VARIABLE_ALIST member.  A return value of NULL indicates
 204    that no variable could be read. */
 205 VARIABLE_ALIST *
 206 read_variable_name (char *prompt, WINDOW *window)
 207 {
 208   register int i;
 209   char *line;
 210   REFERENCE **variables;
 211
 212   /* Get the completion array of variable names. */
 213   variables = make_variable_completions_array ();
 214
 215   /* Ask the completer to read a variable for us. */
 216   line =
 217     info_read_completing_in_echo_area (window, prompt, variables);
 218
 219   info_free_references (variables);
 220
 221   if (!echo_area_is_active)
 222     window_clear_echo_area ();
 223
 224   /* User aborted? */
 225   if (!line)
 226     {
 227       info_abort_key (active_window, 0, 0);
 228       return ((VARIABLE_ALIST *)NULL);
 229     }
 230
 231   /* User accepted "default"?  (There is none.) */
 232   if (!*line)
 233     {
 234       free (line);
 235       return ((VARIABLE_ALIST *)NULL);
 236     }
 237
 238   /* Find the variable in our list of variables. */
 239   for (i = 0; info_variables[i].name; i++)
 240     if (strcmp (info_variables[i].name, line) == 0)
 241       break;
 242
 243   if (!info_variables[i].name)
 244     return ((VARIABLE_ALIST *)NULL);
 245   else
 246     return (&(info_variables[i]));
 247 }
 248
 249 /* Make an array of REFERENCE which actually contains the names of the
 250    variables available in Info. */
 251 REFERENCE **
 252 make_variable_completions_array (void)
 253 {
 254   register int i;
 255   REFERENCE **array = (REFERENCE **)NULL;
 256   int array_index = 0, array_slots = 0;
 257
 258   for (i = 0; info_variables[i].name; i++)
 259     {
 260       REFERENCE *entry;
 261
 262       entry = (REFERENCE *) xmalloc (sizeof (REFERENCE));
 263       entry->label = xstrdup (info_variables[i].name);
 264       entry->nodename = (char *)NULL;
 265       entry->filename = (char *)NULL;
 266
 267       add_pointer_to_array
 268         (entry, array_index, array, array_slots, 200, REFERENCE *);
 269     }
 270
 271   return (array);
 272 }
 273
 274 #if defined(INFOKEY)
 275
 276 void
 277 set_variable_to_value(char *name, char *value)
 278 {
 279         register int i;
 280
 281         /* Find the variable in our list of variables. */
 282         for (i = 0; info_variables[i].name; i++)
 283                 if (strcmp(info_variables[i].name, name) == 0)
 284                         break;
 285
 286         if (!info_variables[i].name)
 287                 return;
 288
 289         if (info_variables[i].choices)
 290         {
 291                 register int j;
 292
 293                 /* Find the choice in our list of choices. */
 294                 for (j = 0; info_variables[i].choices[j]; j++)
 295                         if (strcmp (info_variables[i].choices[j], value) == 0)
 296                                 break;
 297
 298                 if (info_variables[i].choices[j])
 299                         *info_variables[i].value = j;
 300         }
 301         else
 302         {
 303                 *info_variables[i].value = atoi(value);
 304         }
 305 }
 306
 307 #endif /* INFOKEY */