1 /*
2 * Copyright (C) 1984-2021 Mark Nudelman
3 *
4 * You may distribute under the terms of either the GNU General Public
5 * License or the Less License, as specified in the README file.
6 *
7 * For more information, see the README file.
8 */
9
10
11 /*
12 * The option table.
13 */
14
15 #include "less.h"
16 #include "option.h"
17
18 /*
19 * Variables controlled by command line options.
20 */
21 public int quiet; /* Should we suppress the audible bell? */
22 public int how_search; /* Where should forward searches start? */
23 public int top_scroll; /* Repaint screen from top?
24 (alternative is scroll from bottom) */
25 public int pr_type; /* Type of prompt (short, medium, long) */
26 public int bs_mode; /* How to process backspaces */
27 public int know_dumb; /* Don't complain about dumb terminals */
28 public int quit_at_eof; /* Quit after hitting end of file twice */
29 public int quit_if_one_screen; /* Quit if EOF on first screen */
30 public int squeeze; /* Squeeze multiple blank lines into one */
31 public int tabstop; /* Tab settings */
32 public int back_scroll; /* Repaint screen on backwards movement */
33 public int forw_scroll; /* Repaint screen on forward movement */
34 public int caseless; /* Do "caseless" searches */
35 public int linenums; /* Use line numbers */
36 public int autobuf; /* Automatically allocate buffers as needed */
37 public int bufspace; /* Max buffer space per file (K) */
38 public int ctldisp; /* Send control chars to screen untranslated */
39 public int force_open; /* Open the file even if not regular file */
40 public int swindow; /* Size of scrolling window */
41 public int jump_sline; /* Screen line of "jump target" */
42 public long jump_sline_fraction = -1;
43 public long shift_count_fraction = -1;
44 public int chopline; /* Truncate displayed lines at screen width */
45 public int no_init; /* Disable sending ti/te termcap strings */
46 public int no_keypad; /* Disable sending ks/ke termcap strings */
47 public int twiddle; /* Show tildes after EOF */
48 public int show_attn; /* Hilite first unread line */
49 public int shift_count; /* Number of positions to shift horizontally */
50 public int status_col; /* Display a status column */
51 public int use_lessopen; /* Use the LESSOPEN filter */
52 public int quit_on_intr; /* Quit on interrupt */
53 public int follow_mode; /* F cmd Follows file desc or file name? */
54 public int oldbot; /* Old bottom of screen behavior {{REMOVE}} */
55 public int opt_use_backslash; /* Use backslash escaping in option parsing */
56 public char rscroll_char; /* Char which marks chopped lines with -S */
57 public int rscroll_attr; /* Attribute of rscroll_char */
58 public int no_hist_dups; /* Remove dups from history list */
59 public int mousecap; /* Allow mouse for scrolling */
60 public int wheel_lines; /* Number of lines to scroll on mouse wheel scroll */
61 public int perma_marks; /* Save marks in history file */
62 public int linenum_width; /* Width of line numbers */
63 public int status_col_width; /* Width of status column */
64 public int incr_search; /* Incremental search */
65 public int use_color; /* Use UI color */
66 #if HILITE_SEARCH
67 public int hilite_search; /* Highlight matched search patterns? */
68 #endif
69
70 public int less_is_more = 0; /* Make compatible with POSIX more */
71
72 /*
73 * Long option names.
74 */
75 static struct optname a_optname = { "search-skip-screen", NULL };
76 static struct optname b_optname = { "buffers", NULL };
77 static struct optname B__optname = { "auto-buffers", NULL };
78 static struct optname c_optname = { "clear-screen", NULL };
79 static struct optname d_optname = { "dumb", NULL };
80 static struct optname D__optname = { "color", NULL };
81 static struct optname e_optname = { "quit-at-eof", NULL };
82 static struct optname f_optname = { "force", NULL };
83 static struct optname F__optname = { "quit-if-one-screen", NULL };
84 #if HILITE_SEARCH
85 static struct optname g_optname = { "hilite-search", NULL };
86 #endif
87 static struct optname h_optname = { "max-back-scroll", NULL };
88 static struct optname i_optname = { "ignore-case", NULL };
89 static struct optname j_optname = { "jump-target", NULL };
90 static struct optname J__optname = { "status-column", NULL };
91 #if USERFILE
92 static struct optname k_optname = { "lesskey-file", NULL };
93 #endif
94 static struct optname K__optname = { "quit-on-intr", NULL };
95 static struct optname L__optname = { "no-lessopen", NULL };
96 static struct optname m_optname = { "long-prompt", NULL };
97 static struct optname n_optname = { "line-numbers", NULL };
98 #if LOGFILE
99 static struct optname o_optname = { "log-file", NULL };
100 static struct optname O__optname = { "LOG-FILE", NULL };
101 #endif
102 static struct optname p_optname = { "pattern", NULL };
103 static struct optname P__optname = { "prompt", NULL };
104 static struct optname q2_optname = { "silent", NULL };
105 static struct optname q_optname = { "quiet", &q2_optname };
106 static struct optname r_optname = { "raw-control-chars", NULL };
107 static struct optname s_optname = { "squeeze-blank-lines", NULL };
108 static struct optname S__optname = { "chop-long-lines", NULL };
109 #if TAGS
110 static struct optname t_optname = { "tag", NULL };
111 static struct optname T__optname = { "tag-file", NULL };
112 #endif
113 static struct optname u_optname = { "underline-special", NULL };
114 static struct optname V__optname = { "version", NULL };
115 static struct optname w_optname = { "hilite-unread", NULL };
116 static struct optname x_optname = { "tabs", NULL };
117 static struct optname X__optname = { "no-init", NULL };
118 static struct optname y_optname = { "max-forw-scroll", NULL };
119 static struct optname z_optname = { "window", NULL };
120 static struct optname quote_optname = { "quotes", NULL };
121 static struct optname tilde_optname = { "tilde", NULL };
122 static struct optname query_optname = { "help", NULL };
123 static struct optname pound_optname = { "shift", NULL };
124 static struct optname keypad_optname = { "no-keypad", NULL };
125 static struct optname oldbot_optname = { "old-bot", NULL };
126 static struct optname follow_optname = { "follow-name", NULL };
127 static struct optname use_backslash_optname = { "use-backslash", NULL };
128 static struct optname rscroll_optname = { "rscroll", NULL };
129 static struct optname nohistdups_optname = { "no-histdups", NULL };
130 static struct optname mousecap_optname = { "mouse", NULL };
131 static struct optname wheel_lines_optname = { "wheel-lines", NULL };
132 static struct optname perma_marks_optname = { "save-marks", NULL };
133 static struct optname linenum_width_optname = { "line-num-width", NULL };
134 static struct optname status_col_width_optname = { "status-col-width", NULL };
135 static struct optname incr_search_optname = { "incsearch", NULL };
136 static struct optname use_color_optname = { "use-color", NULL };
137 #if LESSTEST
138 static struct optname ttyin_name_optname = { "tty", NULL };
139 static struct optname rstat_optname = { "rstat", NULL };
140 #endif /*LESSTEST*/
141
142
143 /*
144 * Table of all options and their semantics.
145 *
146 * For BOOL and TRIPLE options, odesc[0], odesc[1], odesc[2] are
147 * the description of the option when set to 0, 1 or 2, respectively.
148 * For NUMBER options, odesc[0] is the prompt to use when entering
149 * a new value, and odesc[1] is the description, which should contain
150 * one %d which is replaced by the value of the number.
151 * For STRING options, odesc[0] is the prompt to use when entering
152 * a new value, and odesc[1], if not NULL, is the set of characters
153 * that are valid in the string.
154 */
155 static struct loption option[] =
156 {
157 { 'a', &a_optname,
158 TRIPLE, OPT_ONPLUS, &how_search, NULL,
159 {
160 "Search includes displayed screen",
161 "Search skips displayed screen",
162 "Search includes all of displayed screen"
163 }
164 },
165
166 { 'b', &b_optname,
167 NUMBER|INIT_HANDLER, 64, &bufspace, opt_b,
168 {
169 "Max buffer space per file (K): ",
170 "Max buffer space per file: %dK",
171 NULL
172 }
173 },
174 { 'B', &B__optname,
175 BOOL, OPT_ON, &autobuf, NULL,
176 {
177 "Don't automatically allocate buffers",
178 "Automatically allocate buffers when needed",
179 NULL
180 }
181 },
182 { 'c', &c_optname,
183 TRIPLE, OPT_OFF, &top_scroll, NULL,
184 {
185 "Repaint by scrolling from bottom of screen",
186 "Repaint by painting from top of screen",
187 "Repaint by painting from top of screen"
188 }
189 },
190 { 'd', &d_optname,
191 BOOL|NO_TOGGLE, OPT_OFF, &know_dumb, NULL,
192 {
193 "Assume intelligent terminal",
194 "Assume dumb terminal",
195 NULL
196 }
197 },
198 { 'D', &D__optname,
199 STRING|REPAINT|NO_QUERY, 0, NULL, opt_D,
200 {
201 "color desc: ",
202 NULL,
203 NULL
204 }
205 },
206 { 'e', &e_optname,
207 TRIPLE, OPT_OFF, &quit_at_eof, NULL,
208 {
209 "Don't quit at end-of-file",
210 "Quit at end-of-file",
211 "Quit immediately at end-of-file"
212 }
213 },
214 { 'f', &f_optname,
215 BOOL, OPT_OFF, &force_open, NULL,
216 {
217 "Open only regular files",
218 "Open even non-regular files",
219 NULL
220 }
221 },
222 { 'F', &F__optname,
223 BOOL, OPT_OFF, &quit_if_one_screen, NULL,
224 {
225 "Don't quit if end-of-file on first screen",
226 "Quit if end-of-file on first screen",
227 NULL
228 }
229 },
230 #if HILITE_SEARCH
231 { 'g', &g_optname,
232 TRIPLE|HL_REPAINT, OPT_ONPLUS, &hilite_search, NULL,
233 {
234 "Don't highlight search matches",
235 "Highlight matches for previous search only",
236 "Highlight all matches for previous search pattern",
237 }
238 },
239 #endif
240 { 'h', &h_optname,
241 NUMBER, -1, &back_scroll, NULL,
242 {
243 "Backwards scroll limit: ",
244 "Backwards scroll limit is %d lines",
245 NULL
246 }
247 },
248 { 'i', &i_optname,
249 TRIPLE|HL_REPAINT, OPT_OFF, &caseless, opt_i,
250 {
251 "Case is significant in searches",
252 "Ignore case in searches",
253 "Ignore case in searches and in patterns"
254 }
255 },
256 { 'j', &j_optname,
257 STRING, 0, NULL, opt_j,
258 {
259 "Target line: ",
260 "0123456789.-",
261 NULL
262 }
263 },
264 { 'J', &J__optname,
265 BOOL|REPAINT, OPT_OFF, &status_col, NULL,
266 {
267 "Don't display a status column",
268 "Display a status column",
269 NULL
270 }
271 },
272 #if USERFILE
273 { 'k', &k_optname,
274 STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_k,
275 { NULL, NULL, NULL }
276 },
277 #endif
278 { 'K', &K__optname,
279 BOOL, OPT_OFF, &quit_on_intr, NULL,
280 {
281 "Interrupt (ctrl-C) returns to prompt",
282 "Interrupt (ctrl-C) exits less",
283 NULL
284 }
285 },
286 { 'L', &L__optname,
287 BOOL, OPT_ON, &use_lessopen, NULL,
288 {
289 "Don't use the LESSOPEN filter",
290 "Use the LESSOPEN filter",
291 NULL
292 }
293 },
294 { 'm', &m_optname,
295 TRIPLE, OPT_OFF, &pr_type, NULL,
296 {
297 "Short prompt",
298 "Medium prompt",
299 "Long prompt"
300 }
301 },
302 { 'n', &n_optname,
303 TRIPLE|REPAINT, OPT_ON, &linenums, NULL,
304 {
305 "Don't use line numbers",
306 "Use line numbers",
307 "Constantly display line numbers"
308 }
309 },
310 #if LOGFILE
311 { 'o', &o_optname,
312 STRING, 0, NULL, opt_o,
313 { "log file: ", NULL, NULL }
314 },
315 { 'O', &O__optname,
316 STRING, 0, NULL, opt__O,
317 { "Log file: ", NULL, NULL }
318 },
319 #endif
320 { 'p', &p_optname,
321 STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_p,
322 { NULL, NULL, NULL }
323 },
324 { 'P', &P__optname,
325 STRING, 0, NULL, opt__P,
326 { "prompt: ", NULL, NULL }
327 },
328 { 'q', &q_optname,
329 TRIPLE, OPT_OFF, &quiet, NULL,
330 {
331 "Ring the bell for errors AND at eof/bof",
332 "Ring the bell for errors but not at eof/bof",
333 "Never ring the bell"
334 }
335 },
336 { 'r', &r_optname,
337 TRIPLE|REPAINT, OPT_OFF, &ctldisp, NULL,
338 {
339 "Display control characters as ^X",
340 "Display control characters directly",
341 "Display control characters directly, processing ANSI sequences"
342 }
343 },
344 { 's', &s_optname,
345 BOOL|REPAINT, OPT_OFF, &squeeze, NULL,
346 {
347 "Display all blank lines",
348 "Squeeze multiple blank lines",
349 NULL
350 }
351 },
352 { 'S', &S__optname,
353 BOOL|REPAINT, OPT_OFF, &chopline, NULL,
354 {
355 "Fold long lines",
356 "Chop long lines",
357 NULL
358 }
359 },
360 #if TAGS
361 { 't', &t_optname,
362 STRING|NO_QUERY, 0, NULL, opt_t,
363 { "tag: ", NULL, NULL }
364 },
365 { 'T', &T__optname,
366 STRING, 0, NULL, opt__T,
367 { "tags file: ", NULL, NULL }
368 },
369 #endif
370 { 'u', &u_optname,
371 TRIPLE|REPAINT, OPT_OFF, &bs_mode, NULL,
372 {
373 "Display underlined text in underline mode",
374 "Backspaces cause overstrike",
375 "Print backspace as ^H"
376 }
377 },
378 { 'V', &V__optname,
379 NOVAR, 0, NULL, opt__V,
380 { NULL, NULL, NULL }
381 },
382 { 'w', &w_optname,
383 TRIPLE|REPAINT, OPT_OFF, &show_attn, NULL,
384 {
385 "Don't highlight first unread line",
386 "Highlight first unread line after forward-screen",
387 "Highlight first unread line after any forward movement",
388 }
389 },
390 { 'x', &x_optname,
391 STRING|REPAINT, 0, NULL, opt_x,
392 {
393 "Tab stops: ",
394 "0123456789,",
395 NULL
396 }
397 },
398 { 'X', &X__optname,
399 BOOL|NO_TOGGLE, OPT_OFF, &no_init, NULL,
400 {
401 "Send init/deinit strings to terminal",
402 "Don't use init/deinit strings",
403 NULL
404 }
405 },
406 { 'y', &y_optname,
407 NUMBER, -1, &forw_scroll, NULL,
408 {
409 "Forward scroll limit: ",
410 "Forward scroll limit is %d lines",
411 NULL
412 }
413 },
414 { 'z', &z_optname,
415 NUMBER, -1, &swindow, NULL,
416 {
417 "Scroll window size: ",
418 "Scroll window size is %d lines",
419 NULL
420 }
421 },
422 { '"', "e_optname,
423 STRING, 0, NULL, opt_quote,
424 { "quotes: ", NULL, NULL }
425 },
426 { '~', &tilde_optname,
427 BOOL|REPAINT, OPT_ON, &twiddle, NULL,
428 {
429 "Don't show tildes after end of file",
430 "Show tildes after end of file",
431 NULL
432 }
433 },
434 { '?', &query_optname,
435 NOVAR, 0, NULL, opt_query,
436 { NULL, NULL, NULL }
437 },
438 { '#', £_optname,
439 STRING, 0, NULL, opt_shift,
440 {
441 "Horizontal shift: ",
442 "0123456789.",
443 NULL
444 }
445 },
446 { OLETTER_NONE, &keypad_optname,
447 BOOL|NO_TOGGLE, OPT_OFF, &no_keypad, NULL,
448 {
449 "Use keypad mode",
450 "Don't use keypad mode",
451 NULL
452 }
453 },
454 { OLETTER_NONE, &oldbot_optname,
455 BOOL, OPT_OFF, &oldbot, NULL,
456 {
457 "Use new bottom of screen behavior",
458 "Use old bottom of screen behavior",
459 NULL
460 }
461 },
462 { OLETTER_NONE, &follow_optname,
463 BOOL, FOLLOW_DESC, &follow_mode, NULL,
464 {
465 "F command follows file descriptor",
466 "F command follows file name",
467 NULL
468 }
469 },
470 { OLETTER_NONE, &use_backslash_optname,
471 BOOL, OPT_OFF, &opt_use_backslash, NULL,
472 {
473 "Use backslash escaping in command line parameters",
474 "Don't use backslash escaping in command line parameters",
475 NULL
476 }
477 },
478 { OLETTER_NONE, &rscroll_optname,
479 STRING|REPAINT|INIT_HANDLER, 0, NULL, opt_rscroll,
480 { "right scroll character: ", NULL, NULL }
481 },
482 { OLETTER_NONE, &nohistdups_optname,
483 BOOL, OPT_OFF, &no_hist_dups, NULL,
484 {
485 "Allow duplicates in history list",
486 "Remove duplicates from history list",
487 NULL
488 }
489 },
490 { OLETTER_NONE, &mousecap_optname,
491 TRIPLE, OPT_OFF, &mousecap, opt_mousecap,
492 {
493 "Ignore mouse input",
494 "Use the mouse for scrolling",
495 "Use the mouse for scrolling (reverse)"
496 }
497 },
498 { OLETTER_NONE, &wheel_lines_optname,
499 NUMBER|INIT_HANDLER, 0, &wheel_lines, opt_wheel_lines,
500 {
501 "Lines to scroll on mouse wheel: ",
502 "Scroll %d line(s) on mouse wheel",
503 NULL
504 }
505 },
506 { OLETTER_NONE, &perma_marks_optname,
507 BOOL, OPT_OFF, &perma_marks, NULL,
508 {
509 "Don't save marks in history file",
510 "Save marks in history file",
511 NULL
512 }
513 },
514 { OLETTER_NONE, &linenum_width_optname,
515 NUMBER|REPAINT, MIN_LINENUM_WIDTH, &linenum_width, opt_linenum_width,
516 {
517 "Line number width: ",
518 "Line number width is %d chars",
519 NULL
520 }
521 },
522 { OLETTER_NONE, &status_col_width_optname,
523 NUMBER|REPAINT, 2, &status_col_width, opt_status_col_width,
524 {
525 "Status column width: ",
526 "Status column width is %d chars",
527 NULL
528 }
529 },
530 { OLETTER_NONE, &incr_search_optname,
531 BOOL, OPT_OFF, &incr_search, NULL,
532 {
533 "Incremental search is off",
534 "Incremental search is on",
535 NULL
536 }
537 },
538 { OLETTER_NONE, &use_color_optname,
539 BOOL|REPAINT, OPT_OFF, &use_color, NULL,
540 {
541 "Don't use color",
542 "Use color",
543 NULL
544 }
545 },
546 #if LESSTEST
547 { OLETTER_NONE, &ttyin_name_optname,
548 STRING|NO_TOGGLE, 0, NULL, opt_ttyin_name,
549 {
550 NULL,
551 NULL,
552 NULL
553 }
554 },
555 { OLETTER_NONE, &rstat_optname,
556 STRING|NO_TOGGLE, 0, NULL, opt_rstat,
557 {
558 NULL,
559 NULL,
560 NULL
561 }
562 },
563 #endif /*LESSTEST*/
564 { '\0', NULL, NOVAR, 0, NULL, NULL, { NULL, NULL, NULL } }
565 };
566
567
568 /*
569 * Initialize each option to its default value.
570 */
571 public void
init_option(VOID_PARAM)572 init_option(VOID_PARAM)
573 {
574 struct loption *o;
575 char *p;
576
577 p = lgetenv("LESS_IS_MORE");
578 if (!isnullenv(p))
579 less_is_more = 1;
580
581 for (o = option; o->oletter != '\0'; o++)
582 {
583 /*
584 * Set each variable to its default.
585 */
586 if (o->ovar != NULL)
587 *(o->ovar) = o->odefault;
588 if (o->otype & INIT_HANDLER)
589 (*(o->ofunc))(INIT, (char *) NULL);
590 }
591 }
592
593 /*
594 * Find an option in the option table, given its option letter.
595 */
596 public struct loption *
findopt(c)597 findopt(c)
598 int c;
599 {
600 struct loption *o;
601
602 for (o = option; o->oletter != '\0'; o++)
603 {
604 if (o->oletter == c)
605 return (o);
606 if ((o->otype & TRIPLE) && ASCII_TO_UPPER(o->oletter) == c)
607 return (o);
608 }
609 return (NULL);
610 }
611
612 /*
613 *
614 */
615 static int
is_optchar(c)616 is_optchar(c)
617 char c;
618 {
619 if (ASCII_IS_UPPER(c))
620 return 1;
621 if (ASCII_IS_LOWER(c))
622 return 1;
623 if (c == '-')
624 return 1;
625 return 0;
626 }
627
628 /*
629 * Find an option in the option table, given its option name.
630 * p_optname is the (possibly partial) name to look for, and
631 * is updated to point after the matched name.
632 * p_oname if non-NULL is set to point to the full option name.
633 */
634 public struct loption *
findopt_name(p_optname,p_oname,p_err)635 findopt_name(p_optname, p_oname, p_err)
636 char **p_optname;
637 char **p_oname;
638 int *p_err;
639 {
640 char *optname = *p_optname;
641 struct loption *o;
642 struct optname *oname;
643 int len;
644 int uppercase;
645 struct loption *maxo = NULL;
646 struct optname *maxoname = NULL;
647 int maxlen = 0;
648 int ambig = 0;
649 int exact = 0;
650
651 /*
652 * Check all options.
653 */
654 for (o = option; o->oletter != '\0'; o++)
655 {
656 /*
657 * Check all names for this option.
658 */
659 for (oname = o->onames; oname != NULL; oname = oname->onext)
660 {
661 /*
662 * Try normal match first (uppercase == 0),
663 * then, then if it's a TRIPLE option,
664 * try uppercase match (uppercase == 1).
665 */
666 for (uppercase = 0; uppercase <= 1; uppercase++)
667 {
668 len = sprefix(optname, oname->oname, uppercase);
669 if (len <= 0 || is_optchar(optname[len]))
670 {
671 /*
672 * We didn't use all of the option name.
673 */
674 continue;
675 }
676 if (!exact && len == maxlen)
677 /*
678 * Already had a partial match,
679 * and now there's another one that
680 * matches the same length.
681 */
682 ambig = 1;
683 else if (len > maxlen)
684 {
685 /*
686 * Found a better match than
687 * the one we had.
688 */
689 maxo = o;
690 maxoname = oname;
691 maxlen = len;
692 ambig = 0;
693 exact = (len == (int)strlen(oname->oname));
694 }
695 if (!(o->otype & TRIPLE))
696 break;
697 }
698 }
699 }
700 if (ambig)
701 {
702 /*
703 * Name matched more than one option.
704 */
705 if (p_err != NULL)
706 *p_err = OPT_AMBIG;
707 return (NULL);
708 }
709 *p_optname = optname + maxlen;
710 if (p_oname != NULL)
711 *p_oname = maxoname == NULL ? NULL : maxoname->oname;
712 return (maxo);
713 }
714