1 /*
2 * Copyright (C) 1984-2015 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 #if HILITE_SEARCH
57 public int hilite_search; /* Highlight matched search patterns? */
58 #endif
59
60 public int less_is_more = 0; /* Make compatible with POSIX more */
61
62 /*
63 * Long option names.
64 */
65 static struct optname a_optname = { "search-skip-screen", NULL };
66 static struct optname b_optname = { "buffers", NULL };
67 static struct optname B__optname = { "auto-buffers", NULL };
68 static struct optname c_optname = { "clear-screen", NULL };
69 static struct optname d_optname = { "dumb", NULL };
70 #if MSDOS_COMPILER
71 static struct optname D__optname = { "color", NULL };
72 #endif
73 static struct optname e_optname = { "quit-at-eof", NULL };
74 static struct optname f_optname = { "force", NULL };
75 static struct optname F__optname = { "quit-if-one-screen", NULL };
76 #if HILITE_SEARCH
77 static struct optname g_optname = { "hilite-search", NULL };
78 #endif
79 static struct optname h_optname = { "max-back-scroll", NULL };
80 static struct optname i_optname = { "ignore-case", NULL };
81 static struct optname j_optname = { "jump-target", NULL };
82 static struct optname J__optname = { "status-column", NULL };
83 #if USERFILE
84 static struct optname k_optname = { "lesskey-file", NULL };
85 #endif
86 static struct optname K__optname = { "quit-on-intr", NULL };
87 static struct optname L__optname = { "no-lessopen", NULL };
88 static struct optname m_optname = { "long-prompt", NULL };
89 static struct optname n_optname = { "line-numbers", NULL };
90 #if LOGFILE
91 static struct optname o_optname = { "log-file", NULL };
92 static struct optname O__optname = { "LOG-FILE", NULL };
93 #endif
94 static struct optname p_optname = { "pattern", NULL };
95 static struct optname P__optname = { "prompt", NULL };
96 static struct optname q2_optname = { "silent", NULL };
97 static struct optname q_optname = { "quiet", &q2_optname };
98 static struct optname r_optname = { "raw-control-chars", NULL };
99 static struct optname s_optname = { "squeeze-blank-lines", NULL };
100 static struct optname S__optname = { "chop-long-lines", NULL };
101 #if TAGS
102 static struct optname t_optname = { "tag", NULL };
103 static struct optname T__optname = { "tag-file", NULL };
104 #endif
105 static struct optname u_optname = { "underline-special", NULL };
106 static struct optname V__optname = { "version", NULL };
107 static struct optname w_optname = { "hilite-unread", NULL };
108 static struct optname x_optname = { "tabs", NULL };
109 static struct optname X__optname = { "no-init", NULL };
110 static struct optname y_optname = { "max-forw-scroll", NULL };
111 static struct optname z_optname = { "window", NULL };
112 static struct optname quote_optname = { "quotes", NULL };
113 static struct optname tilde_optname = { "tilde", NULL };
114 static struct optname query_optname = { "help", NULL };
115 static struct optname pound_optname = { "shift", NULL };
116 static struct optname keypad_optname = { "no-keypad", NULL };
117 static struct optname oldbot_optname = { "old-bot", NULL };
118 static struct optname follow_optname = { "follow-name", NULL };
119 static struct optname use_backslash_optname = { "use-backslash", NULL };
120
121
122 /*
123 * Table of all options and their semantics.
124 *
125 * For BOOL and TRIPLE options, odesc[0], odesc[1], odesc[2] are
126 * the description of the option when set to 0, 1 or 2, respectively.
127 * For NUMBER options, odesc[0] is the prompt to use when entering
128 * a new value, and odesc[1] is the description, which should contain
129 * one %d which is replaced by the value of the number.
130 * For STRING options, odesc[0] is the prompt to use when entering
131 * a new value, and odesc[1], if not NULL, is the set of characters
132 * that are valid in the string.
133 */
134 static struct loption option[] =
135 {
136 { 'a', &a_optname,
137 TRIPLE, OPT_ONPLUS, &how_search, NULL,
138 {
139 "Search includes displayed screen",
140 "Search skips displayed screen",
141 "Search includes all of displayed screen"
142 }
143 },
144
145 { 'b', &b_optname,
146 NUMBER|INIT_HANDLER, 64, &bufspace, opt_b,
147 {
148 "Max buffer space per file (K): ",
149 "Max buffer space per file: %dK",
150 NULL
151 }
152 },
153 { 'B', &B__optname,
154 BOOL, OPT_ON, &autobuf, NULL,
155 {
156 "Don't automatically allocate buffers",
157 "Automatically allocate buffers when needed",
158 NULL
159 }
160 },
161 { 'c', &c_optname,
162 TRIPLE, OPT_OFF, &top_scroll, NULL,
163 {
164 "Repaint by scrolling from bottom of screen",
165 "Repaint by painting from top of screen",
166 "Repaint by painting from top of screen"
167 }
168 },
169 { 'd', &d_optname,
170 BOOL|NO_TOGGLE, OPT_OFF, &know_dumb, NULL,
171 {
172 "Assume intelligent terminal",
173 "Assume dumb terminal",
174 NULL
175 }
176 },
177 #if MSDOS_COMPILER
178 { 'D', &D__optname,
179 STRING|REPAINT|NO_QUERY, 0, NULL, opt_D,
180 {
181 "color desc: ",
182 "Ddknsu0123456789.",
183 NULL
184 }
185 },
186 #endif
187 { 'e', &e_optname,
188 TRIPLE, OPT_OFF, &quit_at_eof, NULL,
189 {
190 "Don't quit at end-of-file",
191 "Quit at end-of-file",
192 "Quit immediately at end-of-file"
193 }
194 },
195 { 'f', &f_optname,
196 BOOL, OPT_OFF, &force_open, NULL,
197 {
198 "Open only regular files",
199 "Open even non-regular files",
200 NULL
201 }
202 },
203 { 'F', &F__optname,
204 BOOL, OPT_OFF, &quit_if_one_screen, NULL,
205 {
206 "Don't quit if end-of-file on first screen",
207 "Quit if end-of-file on first screen",
208 NULL
209 }
210 },
211 #if HILITE_SEARCH
212 { 'g', &g_optname,
213 TRIPLE|HL_REPAINT, OPT_ONPLUS, &hilite_search, NULL,
214 {
215 "Don't highlight search matches",
216 "Highlight matches for previous search only",
217 "Highlight all matches for previous search pattern",
218 }
219 },
220 #endif
221 { 'h', &h_optname,
222 NUMBER, -1, &back_scroll, NULL,
223 {
224 "Backwards scroll limit: ",
225 "Backwards scroll limit is %d lines",
226 NULL
227 }
228 },
229 { 'i', &i_optname,
230 TRIPLE|HL_REPAINT, OPT_OFF, &caseless, opt_i,
231 {
232 "Case is significant in searches",
233 "Ignore case in searches",
234 "Ignore case in searches and in patterns"
235 }
236 },
237 { 'j', &j_optname,
238 STRING, 0, NULL, opt_j,
239 {
240 "Target line: ",
241 "0123456789.-",
242 NULL
243 }
244 },
245 { 'J', &J__optname,
246 BOOL|REPAINT, OPT_OFF, &status_col, NULL,
247 {
248 "Don't display a status column",
249 "Display a status column",
250 NULL
251 }
252 },
253 #if USERFILE
254 { 'k', &k_optname,
255 STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_k,
256 { NULL, NULL, NULL }
257 },
258 #endif
259 { 'K', &K__optname,
260 BOOL, OPT_OFF, &quit_on_intr, NULL,
261 {
262 "Interrupt (ctrl-C) returns to prompt",
263 "Interrupt (ctrl-C) exits less",
264 NULL
265 }
266 },
267 { 'L', &L__optname,
268 BOOL, OPT_ON, &use_lessopen, NULL,
269 {
270 "Don't use the LESSOPEN filter",
271 "Use the LESSOPEN filter",
272 NULL
273 }
274 },
275 { 'm', &m_optname,
276 TRIPLE, OPT_OFF, &pr_type, NULL,
277 {
278 "Short prompt",
279 "Medium prompt",
280 "Long prompt"
281 }
282 },
283 { 'n', &n_optname,
284 TRIPLE|REPAINT, OPT_ON, &linenums, NULL,
285 {
286 "Don't use line numbers",
287 "Use line numbers",
288 "Constantly display line numbers"
289 }
290 },
291 #if LOGFILE
292 { 'o', &o_optname,
293 STRING, 0, NULL, opt_o,
294 { "log file: ", NULL, NULL }
295 },
296 { 'O', &O__optname,
297 STRING, 0, NULL, opt__O,
298 { "Log file: ", NULL, NULL }
299 },
300 #endif
301 { 'p', &p_optname,
302 STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_p,
303 { NULL, NULL, NULL }
304 },
305 { 'P', &P__optname,
306 STRING, 0, NULL, opt__P,
307 { "prompt: ", NULL, NULL }
308 },
309 { 'q', &q_optname,
310 TRIPLE, OPT_OFF, &quiet, NULL,
311 {
312 "Ring the bell for errors AND at eof/bof",
313 "Ring the bell for errors but not at eof/bof",
314 "Never ring the bell"
315 }
316 },
317 { 'r', &r_optname,
318 TRIPLE|REPAINT, OPT_OFF, &ctldisp, NULL,
319 {
320 "Display control characters as ^X",
321 "Display control characters directly",
322 "Display control characters directly, processing ANSI sequences"
323 }
324 },
325 { 's', &s_optname,
326 BOOL|REPAINT, OPT_OFF, &squeeze, NULL,
327 {
328 "Display all blank lines",
329 "Squeeze multiple blank lines",
330 NULL
331 }
332 },
333 { 'S', &S__optname,
334 BOOL|REPAINT, OPT_OFF, &chopline, NULL,
335 {
336 "Fold long lines",
337 "Chop long lines",
338 NULL
339 }
340 },
341 #if TAGS
342 { 't', &t_optname,
343 STRING|NO_QUERY, 0, NULL, opt_t,
344 { "tag: ", NULL, NULL }
345 },
346 { 'T', &T__optname,
347 STRING, 0, NULL, opt__T,
348 { "tags file: ", NULL, NULL }
349 },
350 #endif
351 { 'u', &u_optname,
352 TRIPLE|REPAINT, OPT_OFF, &bs_mode, NULL,
353 {
354 "Display underlined text in underline mode",
355 "Backspaces cause overstrike",
356 "Print backspace as ^H"
357 }
358 },
359 { 'V', &V__optname,
360 NOVAR, 0, NULL, opt__V,
361 { NULL, NULL, NULL }
362 },
363 { 'w', &w_optname,
364 TRIPLE|REPAINT, OPT_OFF, &show_attn, NULL,
365 {
366 "Don't highlight first unread line",
367 "Highlight first unread line after forward-screen",
368 "Highlight first unread line after any forward movement",
369 }
370 },
371 { 'x', &x_optname,
372 STRING|REPAINT, 0, NULL, opt_x,
373 {
374 "Tab stops: ",
375 "0123456789,",
376 NULL
377 }
378 },
379 { 'X', &X__optname,
380 BOOL|NO_TOGGLE, OPT_OFF, &no_init, NULL,
381 {
382 "Send init/deinit strings to terminal",
383 "Don't use init/deinit strings",
384 NULL
385 }
386 },
387 { 'y', &y_optname,
388 NUMBER, -1, &forw_scroll, NULL,
389 {
390 "Forward scroll limit: ",
391 "Forward scroll limit is %d lines",
392 NULL
393 }
394 },
395 { 'z', &z_optname,
396 NUMBER, -1, &swindow, NULL,
397 {
398 "Scroll window size: ",
399 "Scroll window size is %d lines",
400 NULL
401 }
402 },
403 { '"', "e_optname,
404 STRING, 0, NULL, opt_quote,
405 { "quotes: ", NULL, NULL }
406 },
407 { '~', &tilde_optname,
408 BOOL|REPAINT, OPT_ON, &twiddle, NULL,
409 {
410 "Don't show tildes after end of file",
411 "Show tildes after end of file",
412 NULL
413 }
414 },
415 { '?', &query_optname,
416 NOVAR, 0, NULL, opt_query,
417 { NULL, NULL, NULL }
418 },
419 { '#', £_optname,
420 STRING, 0, NULL, opt_shift,
421 {
422 "Horizontal shift: ",
423 "0123456789.",
424 NULL
425 }
426 },
427 { OLETTER_NONE, &keypad_optname,
428 BOOL|NO_TOGGLE, OPT_OFF, &no_keypad, NULL,
429 {
430 "Use keypad mode",
431 "Don't use keypad mode",
432 NULL
433 }
434 },
435 { OLETTER_NONE, &oldbot_optname,
436 BOOL, OPT_OFF, &oldbot, NULL,
437 {
438 "Use new bottom of screen behavior",
439 "Use old bottom of screen behavior",
440 NULL
441 }
442 },
443 { OLETTER_NONE, &follow_optname,
444 BOOL, FOLLOW_DESC, &follow_mode, NULL,
445 {
446 "F command follows file descriptor",
447 "F command follows file name",
448 NULL
449 }
450 },
451 { OLETTER_NONE, &use_backslash_optname,
452 BOOL, OPT_OFF, &opt_use_backslash, NULL,
453 {
454 "Use backslash escaping in command line parameters",
455 "Don't use backslash escaping in command line parameters",
456 NULL
457 }
458 },
459 { '\0', NULL, NOVAR, 0, NULL, NULL, { NULL, NULL, NULL } }
460 };
461
462
463 /*
464 * Initialize each option to its default value.
465 */
466 public void
init_option()467 init_option()
468 {
469 register struct loption *o;
470 char *p;
471
472 p = lgetenv("LESS_IS_MORE");
473 if (p != NULL && *p != '\0')
474 less_is_more = 1;
475
476 for (o = option; o->oletter != '\0'; o++)
477 {
478 /*
479 * Set each variable to its default.
480 */
481 if (o->ovar != NULL)
482 *(o->ovar) = o->odefault;
483 if (o->otype & INIT_HANDLER)
484 (*(o->ofunc))(INIT, (char *) NULL);
485 }
486 }
487
488 /*
489 * Find an option in the option table, given its option letter.
490 */
491 public struct loption *
findopt(c)492 findopt(c)
493 int c;
494 {
495 register struct loption *o;
496
497 for (o = option; o->oletter != '\0'; o++)
498 {
499 if (o->oletter == c)
500 return (o);
501 if ((o->otype & TRIPLE) && ASCII_TO_UPPER(o->oletter) == c)
502 return (o);
503 }
504 return (NULL);
505 }
506
507 /*
508 *
509 */
510 static int
is_optchar(c)511 is_optchar(c)
512 char c;
513 {
514 if (ASCII_IS_UPPER(c))
515 return 1;
516 if (ASCII_IS_LOWER(c))
517 return 1;
518 if (c == '-')
519 return 1;
520 return 0;
521 }
522
523 /*
524 * Find an option in the option table, given its option name.
525 * p_optname is the (possibly partial) name to look for, and
526 * is updated to point after the matched name.
527 * p_oname if non-NULL is set to point to the full option name.
528 */
529 public struct loption *
findopt_name(p_optname,p_oname,p_err)530 findopt_name(p_optname, p_oname, p_err)
531 char **p_optname;
532 char **p_oname;
533 int *p_err;
534 {
535 char *optname = *p_optname;
536 register struct loption *o;
537 register struct optname *oname;
538 register int len;
539 int uppercase;
540 struct loption *maxo = NULL;
541 struct optname *maxoname = NULL;
542 int maxlen = 0;
543 int ambig = 0;
544 int exact = 0;
545
546 /*
547 * Check all options.
548 */
549 for (o = option; o->oletter != '\0'; o++)
550 {
551 /*
552 * Check all names for this option.
553 */
554 for (oname = o->onames; oname != NULL; oname = oname->onext)
555 {
556 /*
557 * Try normal match first (uppercase == 0),
558 * then, then if it's a TRIPLE option,
559 * try uppercase match (uppercase == 1).
560 */
561 for (uppercase = 0; uppercase <= 1; uppercase++)
562 {
563 len = sprefix(optname, oname->oname, uppercase);
564 if (len <= 0 || is_optchar(optname[len]))
565 {
566 /*
567 * We didn't use all of the option name.
568 */
569 continue;
570 }
571 if (!exact && len == maxlen)
572 /*
573 * Already had a partial match,
574 * and now there's another one that
575 * matches the same length.
576 */
577 ambig = 1;
578 else if (len > maxlen)
579 {
580 /*
581 * Found a better match than
582 * the one we had.
583 */
584 maxo = o;
585 maxoname = oname;
586 maxlen = len;
587 ambig = 0;
588 exact = (len == (int)strlen(oname->oname));
589 }
590 if (!(o->otype & TRIPLE))
591 break;
592 }
593 }
594 }
595 if (ambig)
596 {
597 /*
598 * Name matched more than one option.
599 */
600 if (p_err != NULL)
601 *p_err = OPT_AMBIG;
602 return (NULL);
603 }
604 *p_optname = optname + maxlen;
605 if (p_oname != NULL)
606 *p_oname = maxoname == NULL ? NULL : maxoname->oname;
607 return (maxo);
608 }
609