1 /*
2 * Copyright (C) 1984-2017 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 LWCHAR rscroll_char; /* Char which marks chopped lines with -S */
57 public int rscroll_attr; /* Attribute of rscroll_char */
58 #if HILITE_SEARCH
59 public int hilite_search; /* Highlight matched search patterns? */
60 #endif
61
62 public int less_is_more = 0; /* Make compatible with POSIX more */
63
64 /*
65 * Long option names.
66 */
67 static struct optname a_optname = { "search-skip-screen", NULL };
68 static struct optname b_optname = { "buffers", NULL };
69 static struct optname B__optname = { "auto-buffers", NULL };
70 static struct optname c_optname = { "clear-screen", NULL };
71 static struct optname d_optname = { "dumb", NULL };
72 #if MSDOS_COMPILER
73 static struct optname D__optname = { "color", NULL };
74 #endif
75 static struct optname e_optname = { "quit-at-eof", NULL };
76 static struct optname f_optname = { "force", NULL };
77 static struct optname F__optname = { "quit-if-one-screen", NULL };
78 #if HILITE_SEARCH
79 static struct optname g_optname = { "hilite-search", NULL };
80 #endif
81 static struct optname h_optname = { "max-back-scroll", NULL };
82 static struct optname i_optname = { "ignore-case", NULL };
83 static struct optname j_optname = { "jump-target", NULL };
84 static struct optname J__optname = { "status-column", NULL };
85 #if USERFILE
86 static struct optname k_optname = { "lesskey-file", NULL };
87 #endif
88 static struct optname K__optname = { "quit-on-intr", NULL };
89 static struct optname L__optname = { "no-lessopen", NULL };
90 static struct optname m_optname = { "long-prompt", NULL };
91 static struct optname n_optname = { "line-numbers", NULL };
92 #if LOGFILE
93 static struct optname o_optname = { "log-file", NULL };
94 static struct optname O__optname = { "LOG-FILE", NULL };
95 #endif
96 static struct optname p_optname = { "pattern", NULL };
97 static struct optname P__optname = { "prompt", NULL };
98 static struct optname q2_optname = { "silent", NULL };
99 static struct optname q_optname = { "quiet", &q2_optname };
100 static struct optname r_optname = { "raw-control-chars", NULL };
101 static struct optname s_optname = { "squeeze-blank-lines", NULL };
102 static struct optname S__optname = { "chop-long-lines", NULL };
103 #if TAGS
104 static struct optname t_optname = { "tag", NULL };
105 static struct optname T__optname = { "tag-file", NULL };
106 #endif
107 static struct optname u_optname = { "underline-special", NULL };
108 static struct optname V__optname = { "version", NULL };
109 static struct optname w_optname = { "hilite-unread", NULL };
110 static struct optname x_optname = { "tabs", NULL };
111 static struct optname X__optname = { "no-init", NULL };
112 static struct optname y_optname = { "max-forw-scroll", NULL };
113 static struct optname z_optname = { "window", NULL };
114 static struct optname quote_optname = { "quotes", NULL };
115 static struct optname tilde_optname = { "tilde", NULL };
116 static struct optname query_optname = { "help", NULL };
117 static struct optname pound_optname = { "shift", NULL };
118 static struct optname keypad_optname = { "no-keypad", NULL };
119 static struct optname oldbot_optname = { "old-bot", NULL };
120 static struct optname follow_optname = { "follow-name", NULL };
121 static struct optname use_backslash_optname = { "use-backslash", NULL };
122 static struct optname rscroll_optname = { "rscroll", NULL };
123
124
125 /*
126 * Table of all options and their semantics.
127 *
128 * For BOOL and TRIPLE options, odesc[0], odesc[1], odesc[2] are
129 * the description of the option when set to 0, 1 or 2, respectively.
130 * For NUMBER options, odesc[0] is the prompt to use when entering
131 * a new value, and odesc[1] is the description, which should contain
132 * one %d which is replaced by the value of the number.
133 * For STRING options, odesc[0] is the prompt to use when entering
134 * a new value, and odesc[1], if not NULL, is the set of characters
135 * that are valid in the string.
136 */
137 static struct loption option[] =
138 {
139 { 'a', &a_optname,
140 TRIPLE, OPT_ONPLUS, &how_search, NULL,
141 {
142 "Search includes displayed screen",
143 "Search skips displayed screen",
144 "Search includes all of displayed screen"
145 }
146 },
147
148 { 'b', &b_optname,
149 NUMBER|INIT_HANDLER, 64, &bufspace, opt_b,
150 {
151 "Max buffer space per file (K): ",
152 "Max buffer space per file: %dK",
153 NULL
154 }
155 },
156 { 'B', &B__optname,
157 BOOL, OPT_ON, &autobuf, NULL,
158 {
159 "Don't automatically allocate buffers",
160 "Automatically allocate buffers when needed",
161 NULL
162 }
163 },
164 { 'c', &c_optname,
165 TRIPLE, OPT_OFF, &top_scroll, NULL,
166 {
167 "Repaint by scrolling from bottom of screen",
168 "Repaint by painting from top of screen",
169 "Repaint by painting from top of screen"
170 }
171 },
172 { 'd', &d_optname,
173 BOOL|NO_TOGGLE, OPT_OFF, &know_dumb, NULL,
174 {
175 "Assume intelligent terminal",
176 "Assume dumb terminal",
177 NULL
178 }
179 },
180 #if MSDOS_COMPILER
181 { 'D', &D__optname,
182 STRING|REPAINT, 0, NULL, opt_D,
183 {
184 "color desc: ",
185 "Dadknsu0123456789.",
186 NULL
187 }
188 },
189 #endif
190 { 'e', &e_optname,
191 TRIPLE, OPT_OFF, &quit_at_eof, NULL,
192 {
193 "Don't quit at end-of-file",
194 "Quit at end-of-file",
195 "Quit immediately at end-of-file"
196 }
197 },
198 { 'f', &f_optname,
199 BOOL, OPT_OFF, &force_open, NULL,
200 {
201 "Open only regular files",
202 "Open even non-regular files",
203 NULL
204 }
205 },
206 { 'F', &F__optname,
207 BOOL, OPT_OFF, &quit_if_one_screen, NULL,
208 {
209 "Don't quit if end-of-file on first screen",
210 "Quit if end-of-file on first screen",
211 NULL
212 }
213 },
214 #if HILITE_SEARCH
215 { 'g', &g_optname,
216 TRIPLE|HL_REPAINT, OPT_ONPLUS, &hilite_search, NULL,
217 {
218 "Don't highlight search matches",
219 "Highlight matches for previous search only",
220 "Highlight all matches for previous search pattern",
221 }
222 },
223 #endif
224 { 'h', &h_optname,
225 NUMBER, -1, &back_scroll, NULL,
226 {
227 "Backwards scroll limit: ",
228 "Backwards scroll limit is %d lines",
229 NULL
230 }
231 },
232 { 'i', &i_optname,
233 TRIPLE|HL_REPAINT, OPT_OFF, &caseless, opt_i,
234 {
235 "Case is significant in searches",
236 "Ignore case in searches",
237 "Ignore case in searches and in patterns"
238 }
239 },
240 { 'j', &j_optname,
241 STRING, 0, NULL, opt_j,
242 {
243 "Target line: ",
244 "0123456789.-",
245 NULL
246 }
247 },
248 { 'J', &J__optname,
249 BOOL|REPAINT, OPT_OFF, &status_col, NULL,
250 {
251 "Don't display a status column",
252 "Display a status column",
253 NULL
254 }
255 },
256 #if USERFILE
257 { 'k', &k_optname,
258 STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_k,
259 { NULL, NULL, NULL }
260 },
261 #endif
262 { 'K', &K__optname,
263 BOOL, OPT_OFF, &quit_on_intr, NULL,
264 {
265 "Interrupt (ctrl-C) returns to prompt",
266 "Interrupt (ctrl-C) exits less",
267 NULL
268 }
269 },
270 { 'L', &L__optname,
271 BOOL, OPT_ON, &use_lessopen, NULL,
272 {
273 "Don't use the LESSOPEN filter",
274 "Use the LESSOPEN filter",
275 NULL
276 }
277 },
278 { 'm', &m_optname,
279 TRIPLE, OPT_OFF, &pr_type, NULL,
280 {
281 "Short prompt",
282 "Medium prompt",
283 "Long prompt"
284 }
285 },
286 { 'n', &n_optname,
287 TRIPLE|REPAINT, OPT_ON, &linenums, NULL,
288 {
289 "Don't use line numbers",
290 "Use line numbers",
291 "Constantly display line numbers"
292 }
293 },
294 #if LOGFILE
295 { 'o', &o_optname,
296 STRING, 0, NULL, opt_o,
297 { "log file: ", NULL, NULL }
298 },
299 { 'O', &O__optname,
300 STRING, 0, NULL, opt__O,
301 { "Log file: ", NULL, NULL }
302 },
303 #endif
304 { 'p', &p_optname,
305 STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_p,
306 { NULL, NULL, NULL }
307 },
308 { 'P', &P__optname,
309 STRING, 0, NULL, opt__P,
310 { "prompt: ", NULL, NULL }
311 },
312 { 'q', &q_optname,
313 TRIPLE, OPT_OFF, &quiet, NULL,
314 {
315 "Ring the bell for errors AND at eof/bof",
316 "Ring the bell for errors but not at eof/bof",
317 "Never ring the bell"
318 }
319 },
320 { 'r', &r_optname,
321 TRIPLE|REPAINT, OPT_OFF, &ctldisp, NULL,
322 {
323 "Display control characters as ^X",
324 "Display control characters directly",
325 "Display control characters directly, processing ANSI sequences"
326 }
327 },
328 { 's', &s_optname,
329 BOOL|REPAINT, OPT_OFF, &squeeze, NULL,
330 {
331 "Display all blank lines",
332 "Squeeze multiple blank lines",
333 NULL
334 }
335 },
336 { 'S', &S__optname,
337 BOOL|REPAINT, OPT_OFF, &chopline, NULL,
338 {
339 "Fold long lines",
340 "Chop long lines",
341 NULL
342 }
343 },
344 #if TAGS
345 { 't', &t_optname,
346 STRING|NO_QUERY, 0, NULL, opt_t,
347 { "tag: ", NULL, NULL }
348 },
349 { 'T', &T__optname,
350 STRING, 0, NULL, opt__T,
351 { "tags file: ", NULL, NULL }
352 },
353 #endif
354 { 'u', &u_optname,
355 TRIPLE|REPAINT, OPT_OFF, &bs_mode, NULL,
356 {
357 "Display underlined text in underline mode",
358 "Backspaces cause overstrike",
359 "Print backspace as ^H"
360 }
361 },
362 { 'V', &V__optname,
363 NOVAR, 0, NULL, opt__V,
364 { NULL, NULL, NULL }
365 },
366 { 'w', &w_optname,
367 TRIPLE|REPAINT, OPT_OFF, &show_attn, NULL,
368 {
369 "Don't highlight first unread line",
370 "Highlight first unread line after forward-screen",
371 "Highlight first unread line after any forward movement",
372 }
373 },
374 { 'x', &x_optname,
375 STRING|REPAINT, 0, NULL, opt_x,
376 {
377 "Tab stops: ",
378 "0123456789,",
379 NULL
380 }
381 },
382 { 'X', &X__optname,
383 BOOL|NO_TOGGLE, OPT_OFF, &no_init, NULL,
384 {
385 "Send init/deinit strings to terminal",
386 "Don't use init/deinit strings",
387 NULL
388 }
389 },
390 { 'y', &y_optname,
391 NUMBER, -1, &forw_scroll, NULL,
392 {
393 "Forward scroll limit: ",
394 "Forward scroll limit is %d lines",
395 NULL
396 }
397 },
398 { 'z', &z_optname,
399 NUMBER, -1, &swindow, NULL,
400 {
401 "Scroll window size: ",
402 "Scroll window size is %d lines",
403 NULL
404 }
405 },
406 { '"', "e_optname,
407 STRING, 0, NULL, opt_quote,
408 { "quotes: ", NULL, NULL }
409 },
410 { '~', &tilde_optname,
411 BOOL|REPAINT, OPT_ON, &twiddle, NULL,
412 {
413 "Don't show tildes after end of file",
414 "Show tildes after end of file",
415 NULL
416 }
417 },
418 { '?', &query_optname,
419 NOVAR, 0, NULL, opt_query,
420 { NULL, NULL, NULL }
421 },
422 { '#', £_optname,
423 STRING, 0, NULL, opt_shift,
424 {
425 "Horizontal shift: ",
426 "0123456789.",
427 NULL
428 }
429 },
430 { OLETTER_NONE, &keypad_optname,
431 BOOL|NO_TOGGLE, OPT_OFF, &no_keypad, NULL,
432 {
433 "Use keypad mode",
434 "Don't use keypad mode",
435 NULL
436 }
437 },
438 { OLETTER_NONE, &oldbot_optname,
439 BOOL, OPT_OFF, &oldbot, NULL,
440 {
441 "Use new bottom of screen behavior",
442 "Use old bottom of screen behavior",
443 NULL
444 }
445 },
446 { OLETTER_NONE, &follow_optname,
447 BOOL, FOLLOW_DESC, &follow_mode, NULL,
448 {
449 "F command follows file descriptor",
450 "F command follows file name",
451 NULL
452 }
453 },
454 { OLETTER_NONE, &use_backslash_optname,
455 BOOL, OPT_OFF, &opt_use_backslash, NULL,
456 {
457 "Use backslash escaping in command line parameters",
458 "Don't use backslash escaping in command line parameters",
459 NULL
460 }
461 },
462 { OLETTER_NONE, &rscroll_optname,
463 STRING|REPAINT|INIT_HANDLER, 0, NULL, opt_rscroll,
464 { "right scroll character: ", NULL, NULL }
465 },
466 { '\0', NULL, NOVAR, 0, NULL, NULL, { NULL, NULL, NULL } }
467 };
468
469
470 /*
471 * Initialize each option to its default value.
472 */
473 public void
init_option()474 init_option()
475 {
476 struct loption *o;
477 char *p;
478
479 p = lgetenv("LESS_IS_MORE");
480 if (p != NULL && *p != '\0')
481 less_is_more = 1;
482
483 for (o = option; o->oletter != '\0'; o++)
484 {
485 /*
486 * Set each variable to its default.
487 */
488 if (o->ovar != NULL)
489 *(o->ovar) = o->odefault;
490 if (o->otype & INIT_HANDLER)
491 (*(o->ofunc))(INIT, (char *) NULL);
492 }
493 }
494
495 /*
496 * Find an option in the option table, given its option letter.
497 */
498 public struct loption *
findopt(c)499 findopt(c)
500 int c;
501 {
502 struct loption *o;
503
504 for (o = option; o->oletter != '\0'; o++)
505 {
506 if (o->oletter == c)
507 return (o);
508 if ((o->otype & TRIPLE) && ASCII_TO_UPPER(o->oletter) == c)
509 return (o);
510 }
511 return (NULL);
512 }
513
514 /*
515 *
516 */
517 static int
is_optchar(c)518 is_optchar(c)
519 char c;
520 {
521 if (ASCII_IS_UPPER(c))
522 return 1;
523 if (ASCII_IS_LOWER(c))
524 return 1;
525 if (c == '-')
526 return 1;
527 return 0;
528 }
529
530 /*
531 * Find an option in the option table, given its option name.
532 * p_optname is the (possibly partial) name to look for, and
533 * is updated to point after the matched name.
534 * p_oname if non-NULL is set to point to the full option name.
535 */
536 public struct loption *
findopt_name(p_optname,p_oname,p_err)537 findopt_name(p_optname, p_oname, p_err)
538 char **p_optname;
539 char **p_oname;
540 int *p_err;
541 {
542 char *optname = *p_optname;
543 struct loption *o;
544 struct optname *oname;
545 int len;
546 int uppercase;
547 struct loption *maxo = NULL;
548 struct optname *maxoname = NULL;
549 int maxlen = 0;
550 int ambig = 0;
551 int exact = 0;
552
553 /*
554 * Check all options.
555 */
556 for (o = option; o->oletter != '\0'; o++)
557 {
558 /*
559 * Check all names for this option.
560 */
561 for (oname = o->onames; oname != NULL; oname = oname->onext)
562 {
563 /*
564 * Try normal match first (uppercase == 0),
565 * then, then if it's a TRIPLE option,
566 * try uppercase match (uppercase == 1).
567 */
568 for (uppercase = 0; uppercase <= 1; uppercase++)
569 {
570 len = sprefix(optname, oname->oname, uppercase);
571 if (len <= 0 || is_optchar(optname[len]))
572 {
573 /*
574 * We didn't use all of the option name.
575 */
576 continue;
577 }
578 if (!exact && len == maxlen)
579 /*
580 * Already had a partial match,
581 * and now there's another one that
582 * matches the same length.
583 */
584 ambig = 1;
585 else if (len > maxlen)
586 {
587 /*
588 * Found a better match than
589 * the one we had.
590 */
591 maxo = o;
592 maxoname = oname;
593 maxlen = len;
594 ambig = 0;
595 exact = (len == (int)strlen(oname->oname));
596 }
597 if (!(o->otype & TRIPLE))
598 break;
599 }
600 }
601 }
602 if (ambig)
603 {
604 /*
605 * Name matched more than one option.
606 */
607 if (p_err != NULL)
608 *p_err = OPT_AMBIG;
609 return (NULL);
610 }
611 *p_optname = optname + maxlen;
612 if (p_oname != NULL)
613 *p_oname = maxoname == NULL ? NULL : maxoname->oname;
614 return (maxo);
615 }
616