contrib/texinfo-4/info/variables.c

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