1 /* variables.c -- how to manipulate user visible variables in Info.
2
3 Copyright 1993-2023 Free Software Foundation, Inc.
4
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation, either version 3 of the License, or
8 (at your option) any later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
17
18 Originally written by Brian Fox. */
19
20 #include "info.h"
21 #include "session.h"
22 #include "echo-area.h"
23 #include "variables.h"
24 #include "terminal.h"
25 #include "display.h"
26
27 static VARIABLE_ALIST *read_variable_name (char *prompt, WINDOW *window);
28
29 /* **************************************************************** */
30 /* */
31 /* User Visible Variables in Info */
32 /* */
33 /* **************************************************************** */
34
35 /* Choices used by the completer when reading a zero/non-zero value for
36 a variable. */
37 static char *on_off_choices[] = { "Off", "On", NULL };
38
39 static char *mouse_choices[] = { "Off", "normal-tracking", NULL };
40
41 static char *follow_strategy_choices[] = { "remain", "path", NULL };
42
43 static char *nodeline_choices[] = { "no", "print", "pointers", NULL };
44
45 /* Choices used by the completer when reading a value for the user-visible
46 variable "scroll-behaviour". */
47 static char *info_scroll_choices[] = { "Continuous", "Next Only",
48 "Page Only", NULL };
49
50 /* Choices for the scroll-last-node variable */
51 static char *scroll_last_node_choices[] = { "Stop", "Top", NULL };
52
53 /* Choices for, and indicator of, rendition. */
54 static char *rendition_choices[] = { "black", "red", "green", "yellow", "blue",
55 "magenta", "cyan", "white", "nocolour", "bgblack", "bgred", "bggreen",
56 "bgyellow", "bgblue", "bgmagenta", "bgcyan", "bgwhite", "nobgcolour",
57 "underline", "nounderline", "standout", "nostandout", "bold", "regular",
58 "blink", "noblink", NULL };
59
60 /* Address of this indicates the 'highlight-searches' variable. */
61 static int *highlight_searches;
62
63 /* Note that the 'where_set' field of each element in the array is
64 not given and defaults to 0. */
65 VARIABLE_ALIST info_variables[] = {
66 { "automatic-footnotes",
67 N_("When \"On\", footnotes appear and disappear automatically"),
68 &auto_footnotes_p, (char **)on_off_choices },
69
70 { "automatic-tiling",
71 N_("When \"On\", creating or deleting a window resizes other windows"),
72 &auto_tiling_p, (char **)on_off_choices },
73
74 { "visible-bell",
75 N_("When \"On\", flash the screen instead of ringing the bell"),
76 &terminal_use_visible_bell_p, (char **)on_off_choices },
77
78 { "errors-ring-bell",
79 N_("When \"On\", errors cause the bell to ring"),
80 &info_error_rings_bell_p, (char **)on_off_choices },
81
82 { "gc-compressed-files",
83 N_("When \"On\", Info garbage collects files which had to be uncompressed"),
84 &gc_compressed_files, (char **)on_off_choices },
85 { "show-index-match",
86 N_("When \"On\", the portion of the matched search string is highlighted"),
87 &show_index_match, (char **)on_off_choices },
88
89 { "scroll-behaviour",
90 N_("Controls what happens when scrolling is requested at the end of a node"),
91 &info_scroll_behaviour, (char **)info_scroll_choices },
92
93 /* Alternate spelling */
94 { "scroll-behavior",
95 N_("Same as scroll-behaviour"),
96 &info_scroll_behaviour, (char **)info_scroll_choices },
97
98 { "scroll-step",
99 N_("The number lines to scroll when the cursor moves out of the window"),
100 &window_scroll_step, NULL },
101
102 { "cursor-movement-scrolls",
103 N_("Controls whether scroll-behavior affects cursor movement commands"),
104 &cursor_movement_scrolls_p, (char **)on_off_choices },
105
106 { "ISO-Latin",
107 N_("When \"On\", Info accepts and displays ISO Latin characters"),
108 &ISO_Latin_p, (char **)on_off_choices },
109
110 { "scroll-last-node",
111 N_("What to do when a scrolling command is issued at the end of the "
112 "last node"),
113 &scroll_last_node, (char**)scroll_last_node_choices },
114
115 { "min-search-length",
116 N_("Minimal length of a search string"),
117 &min_search_length, NULL },
118
119 { "search-skip-screen",
120 N_("Skip current window when searching"),
121 &search_skip_screen_p, (char **)on_off_choices },
122
123 { "infopath-no-defaults",
124 N_("Exclude default directories from file search path"),
125 &infopath_no_defaults_p, (char **)on_off_choices },
126
127 { "hide-note-references",
128 N_("Hide some Info file syntax in the text of nodes"),
129 &preprocess_nodes_p, (char **)on_off_choices },
130
131 { "key-time",
132 N_("Length of time in milliseconds to wait for the next byte in a sequence indicating that a key has been pressed"),
133 &key_time, NULL },
134
135 { "mouse",
136 N_("Method to use to track mouse events"),
137 &mouse_protocol, (char **)mouse_choices },
138
139 { "follow-strategy",
140 N_("How to follow a cross-reference"),
141 &follow_strategy, (char **)follow_strategy_choices },
142
143 { "highlight-searches",
144 N_("Highlight search matches"),
145 &highlight_searches, (char **)on_off_choices },
146
147 { "link-style",
148 N_("Styles for links"),
149 &ref_rendition, (char **)rendition_choices },
150
151 { "active-link-style",
152 N_("Styles for active links"),
153 &hl_ref_rendition, (char **)rendition_choices },
154
155 { "match-style",
156 N_("Styles for search matches"),
157 &match_rendition, (char **)rendition_choices },
158
159 { "nodeline",
160 N_("How to print the information line at the start of a node"),
161 &nodeline_print, (char **)nodeline_choices },
162
163 { NULL }
164 };
165
166 static char *
167 rendition_to_string (RENDITION *rendition)
168 {
169 static char string[8 /* nocolour */ + 1 /* comma */
170 + 10 /* nobgcolour */ + 1
171 + 11 /* nounderline */ + 1
172 + 10 /* nostandout */ + 1
173 + 7 /* regular */ + 1
174 + 7 /* noblink */ + 1];
175 unsigned long style;
176 static const char* fg[] = { "black", "red", "green", "yellow", "blue",
177 "magenta", "cyan", "white" };
178 static const char* bg[] = { "bgblack", "bgred", "bggreen", "bgyellow",
179 "bgblue", "bgmagenta", "bgcyan", "bgwhite" };
180
181 *string = '\0';
182
183 if (rendition->mask & BLINK_MASK)
184 strcat (string, rendition->value & BLINK_MASK ? "blink" : "noblink");
185 if (rendition->mask & BOLD_MASK)
186 {
187 if (*string != '\0')
188 strcat (string, ",");
189 strcat (string, rendition->value & BOLD_MASK ? "bold" : "nobold");
190 }
191 if (rendition->mask & STANDOUT_MASK)
192 {
193 if (*string != '\0')
194 strcat (string, ",");
195 strcat (string, rendition->value & STANDOUT_MASK ? "standout" : "nostandout");
196 }
197 if (rendition->mask & UNDERLINE_MASK)
198 {
199 if (*string != '\0')
200 strcat (string, ",");
201 strcat (string, rendition->value & UNDERLINE_MASK ? "underline" : "nounderline");
202 }
203 if (rendition->mask & COLOUR_MASK)
204 {
205 if (*string != '\0')
206 strcat (string, ",");
207 style = rendition->value & COLOUR_MASK;
208 strcat (string, style >= 8 ? fg[style - 8] : "nocolour");
209 }
210 if (rendition->mask & BGCOLOUR_MASK)
211 {
212 if (*string != '\0')
213 strcat (string, ",");
214 style = (rendition->value & BGCOLOUR_MASK) >> 9;
215 strcat (string, style >= 8 ? bg[style - 8] : "nobgcolour");
216 }
217
218 return string;
219 }
220
221 DECLARE_INFO_COMMAND (describe_variable, _("Explain the use of a variable"))
222 {
223 VARIABLE_ALIST *var;
224 char *description;
225
226 /* Get the variable's name. */
227 var = read_variable_name (_("Describe variable: "), window);
228 if (!var)
229 return;
230
231 if (var->choices)
232 xasprintf (&description, "%s (%s): %s.",
233 var->name,
234 var->value == &highlight_searches
235 ? on_off_choices[match_rendition.mask != 0]
236 : var->choices == (char **) &rendition_choices
237 ? rendition_to_string (var->value)
238 : var->choices[*(int *)var->value], _(var->doc));
239 else
240 xasprintf (&description, "%s (%d): %s.",
241 var->name, *(int *)var->value, _(var->doc));
242
243 window_message_in_echo_area ("%s", description);
244 free (description);
245 }
246
247 DECLARE_INFO_COMMAND (set_variable, _("Set the value of an Info variable"))
248 {
249 VARIABLE_ALIST *var;
250 char *line;
251 char prompt[100];
252
253 /* Get the variable's name and value. */
254 var = read_variable_name (_("Set variable: "), window);
255
256 if (!var)
257 return;
258
259 /* Read a new value for this variable. */
260
261 if (!var->choices)
262 {
263 int potential_value;
264
265 if (info_explicit_arg || count != 1)
266 potential_value = count;
267 else
268 potential_value = *(int *)(var->value);
269
270 sprintf (prompt, _("Set %s to value (%d): "),
271 var->name, potential_value);
272 line = info_read_in_echo_area (prompt);
273
274 /* User aborted? */
275 if (!line)
276 return;
277
278 /* If the user specified a value, get that, otherwise, we are done. */
279 canonicalize_whitespace (line);
280
281 set_variable_to_value (var, line, SET_IN_SESSION);
282
283 free (line);
284 }
285 else
286 {
287 register int i;
288 REFERENCE **array = NULL;
289 size_t array_index = 0;
290 size_t array_slots = 0;
291
292 for (i = 0; var->choices[i]; i++)
293 {
294 REFERENCE *entry;
295
296 entry = xmalloc (sizeof (REFERENCE));
297 entry->label = xstrdup (var->choices[i]);
298 entry->nodename = NULL;
299 entry->filename = NULL;
300
301 add_pointer_to_array (entry, array_index, array, array_slots, 10);
302 }
303
304 sprintf (prompt, _("Set %s to value (%s): "),
305 var->name,
306 var->value == &highlight_searches
307 ? on_off_choices[match_rendition.mask != 0]
308 : var->choices == (char **) &rendition_choices
309 ? rendition_to_string (var->value)
310 : var->choices[*(int *)(var->value)]);
311
312 /* Ask the completer to read a variable value for us. */
313 if (var->choices == (char **) &rendition_choices)
314 line = info_read_maybe_completing (prompt, array);
315 else
316 line = info_read_completing_in_echo_area (prompt, array);
317
318 info_free_references (array);
319
320 /* User aborted? */
321 if (!line)
322 {
323 info_abort_key (active_window, 0);
324 return;
325 }
326
327 /* User accepted default choice? If so, no change. */
328 if (!*line)
329 {
330 free (line);
331 return;
332 }
333
334 set_variable_to_value (var, line, SET_IN_SESSION);
335 }
336 }
337
338 VARIABLE_ALIST *
339 variable_by_name (char *name)
340 {
341 int i;
342
343 /* Find the variable in our list of variables. */
344 for (i = 0; info_variables[i].name; i++)
345 if (strcmp (info_variables[i].name, name) == 0)
346 break;
347
348 if (!info_variables[i].name)
349 return NULL;
350 else
351 return &info_variables[i];
352 }
353
354 /* Read the name of an Info variable in the echo area and return the
355 address of a VARIABLE_ALIST member. A return value of NULL indicates
356 that no variable could be read. */
357 static VARIABLE_ALIST *
358 read_variable_name (char *prompt, WINDOW *window)
359 {
360 char *line;
361 REFERENCE **variables;
362
363 /* Get the completion array of variable names. */
364 variables = make_variable_completions_array ();
365
366 /* Ask the completer to read a variable for us. */
367 line = info_read_completing_in_echo_area (prompt, variables);
368
369 info_free_references (variables);
370
371 /* User aborted? */
372 if (!line)
373 {
374 info_abort_key (active_window, 0);
375 return NULL;
376 }
377
378 /* User accepted "default"? (There is none.) */
379 if (!*line)
380 {
381 free (line);
382 return NULL;
383 }
384
385 return variable_by_name (line);
386 }
387
388 /* Make an array of REFERENCE which actually contains the names of the
389 variables available in Info. */
390 REFERENCE **
391 make_variable_completions_array (void)
392 {
393 register int i;
394 REFERENCE **array = NULL;
395 size_t array_index = 0, array_slots = 0;
396
397 for (i = 0; info_variables[i].name; i++)
398 {
399 REFERENCE *entry;
400
401 entry = xmalloc (sizeof (REFERENCE));
402 entry->label = xstrdup (info_variables[i].name);
403 entry->nodename = NULL;
404 entry->filename = NULL;
405
406 add_pointer_to_array (entry, array_index, array, array_slots, 200);
407 }
408
409 return array;
410 }
411
412 /* VALUE is a string that is the value of the variable specified
413 by the user. Update our internal data structure VAR using this
414 information. */
415 int
416 set_variable_to_value (VARIABLE_ALIST *var, char *value, int where)
417 {
418 /* If variable was set elsewhere with a higher priority, don't do
419 anything, but don't indicate an error. */
420 if (var->where_set > where)
421 return 1;
422
423 if (var->choices)
424 {
425 register int j;
426
427 /* "highlight-searches=On" is equivalent to
428 "match-rendition=standout". */
429 if (var->value == &highlight_searches)
430 {
431 if (strcmp (on_off_choices[0], value) == 0)
432 {
433 match_rendition.mask = 0;
434 match_rendition.value = 0;
435 }
436 else
437 {
438 match_rendition.mask = STANDOUT_MASK;
439 match_rendition.value = STANDOUT_MASK;
440 }
441 }
442 else if (var->choices != (char **) &rendition_choices)
443 {
444 /* Find the choice in our list of choices. */
445 for (j = 0; var->choices[j]; j++)
446 if (strcmp (var->choices[j], value) == 0)
447 {
448 *(int *)var->value = j;
449 var->where_set = where;
450 return 1;
451 }
452 }
453 else
454 {
455 static struct {
456 unsigned long mask;
457 unsigned long value;
458 char *name;
459 } styles[] = {
460 COLOUR_MASK, COLOUR_BLACK, "black",
461 COLOUR_MASK, COLOUR_RED, "red",
462 COLOUR_MASK, COLOUR_GREEN, "green",
463 COLOUR_MASK, COLOUR_YELLOW, "yellow",
464 COLOUR_MASK, COLOUR_BLUE, "blue",
465 COLOUR_MASK, COLOUR_MAGENTA, "magenta",
466 COLOUR_MASK, COLOUR_CYAN, "cyan",
467 COLOUR_MASK, COLOUR_WHITE, "white",
468 COLOUR_MASK, 0, "nocolour",
469 COLOUR_MASK, 0, "nocolor",
470 BGCOLOUR_MASK, BGCOLOUR_BLACK, "bgblack",
471 BGCOLOUR_MASK, BGCOLOUR_RED, "bgred",
472 BGCOLOUR_MASK, BGCOLOUR_GREEN, "bggreen",
473 BGCOLOUR_MASK, BGCOLOUR_YELLOW, "bgyellow",
474 BGCOLOUR_MASK, BGCOLOUR_BLUE, "bgblue",
475 BGCOLOUR_MASK, BGCOLOUR_MAGENTA, "bgmagenta",
476 BGCOLOUR_MASK, BGCOLOUR_CYAN, "bgcyan",
477 BGCOLOUR_MASK, BGCOLOUR_WHITE, "bgwhite",
478 BGCOLOUR_MASK, 0, "nobgcolour",
479 BGCOLOUR_MASK, 0, "nobgcolor",
480 UNDERLINE_MASK, UNDERLINE_MASK, "underline",
481 UNDERLINE_MASK, 0, "nounderline",
482 STANDOUT_MASK, STANDOUT_MASK, "standout",
483 STANDOUT_MASK, 0, "nostandout",
484 BOLD_MASK, BOLD_MASK, "bold",
485 BOLD_MASK, 0, "regular",
486 BOLD_MASK, 0, "nobold",
487 BLINK_MASK, BLINK_MASK, "blink",
488 BLINK_MASK, 0, "noblink",
489 };
490 int i;
491 char *component;
492 unsigned long rendition_mask = 0;
493 unsigned long rendition_value = 0;
494
495 component = strtok (value, ",");
496 while (component)
497 {
498 for (i = 0; (styles[i].name); i++)
499 {
500 if (!strcmp (styles[i].name, component))
501 break;
502 }
503 if (styles[i].name)
504 {
505 rendition_mask |= styles[i].mask;
506 rendition_value &= ~styles[i].mask;
507 rendition_value |= styles[i].value;
508 }
509 /* If not found, silently ignore, in case more options are
510 added in the future. */
511
512 component = strtok (0, ",");
513 }
514
515 /* Now all the specified styles are recorded in rendition_value. */
516 ((RENDITION *)var->value)->mask = rendition_mask;
517 ((RENDITION *)var->value)->value = rendition_value;
518 }
519 return 1;
520 }
521 else
522 {
523 char *p;
524 long n = strtol (value, &p, 10);
525 if (*p == 0 && INT_MIN <= n && n <= INT_MAX)
526 {
527 *(int *)var->value = n;
528 return 1;
529 }
530 }
531
532 return 0;
533 }
534