opttbl.c revision 161475
1/*
2 * Copyright (C) 1984-2004  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 about less, or for information on how to
8 * contact the author, see the README file.
9 */
10
11
12/*
13 * The option table.
14 */
15
16#include "less.h"
17#include "option.h"
18
19/*
20 * Variables controlled by command line options.
21 */
22public int quiet;		/* Should we suppress the audible bell? */
23public int how_search;		/* Where should forward searches start? */
24public int top_scroll;		/* Repaint screen from top?
25				   (alternative is scroll from bottom) */
26public int pr_type;		/* Type of prompt (short, medium, long) */
27public int bs_mode;		/* How to process backspaces */
28public int know_dumb;		/* Don't complain about dumb terminals */
29public int quit_at_eof;		/* Quit after hitting end of file twice */
30public int quit_if_one_screen;	/* Quit if EOF on first screen */
31public int squeeze;		/* Squeeze multiple blank lines into one */
32public int tabstop;		/* Tab settings */
33public int back_scroll;		/* Repaint screen on backwards movement */
34public int forw_scroll;		/* Repaint screen on forward movement */
35public int caseless;		/* Do "caseless" searches */
36public int linenums;		/* Use line numbers */
37public int autobuf;		/* Automatically allocate buffers as needed */
38public int bufspace;		/* Max buffer space per file (K) */
39public int ctldisp;		/* Send control chars to screen untranslated */
40public int force_open;		/* Open the file even if not regular file */
41public int swindow;		/* Size of scrolling window */
42public int jump_sline;		/* Screen line of "jump target" */
43public int chopline;		/* Truncate displayed lines at screen width */
44public int no_init;		/* Disable sending ti/te termcap strings */
45public int no_keypad;		/* Disable sending ks/ke termcap strings */
46public int twiddle;             /* Show tildes after EOF */
47public int show_attn;		/* Hilite first unread line */
48public int shift_count;		/* Number of positions to shift horizontally */
49public int status_col;		/* Display a status column */
50public int use_lessopen;	/* Use the LESSOPEN filter */
51public int quit_on_intr;	/* Quit on interrupt */
52#if HILITE_SEARCH
53public int hilite_search;	/* Highlight matched search patterns? */
54#endif
55
56public int less_is_more = 0;	/* Make compatible with POSIX more */
57
58/*
59 * Long option names.
60 */
61static struct optname a_optname      = { "search-skip-screen",   NULL };
62static struct optname b_optname      = { "buffers",              NULL };
63static struct optname B__optname     = { "auto-buffers",         NULL };
64static struct optname c_optname      = { "clear-screen",         NULL };
65static struct optname d_optname      = { "dumb",                 NULL };
66#if MSDOS_COMPILER
67static struct optname D__optname     = { "color",                NULL };
68#endif
69static struct optname e_optname      = { "quit-at-eof",          NULL };
70static struct optname f_optname      = { "force",                NULL };
71static struct optname F__optname     = { "quit-if-one-screen",   NULL };
72#if HILITE_SEARCH
73static struct optname g_optname      = { "hilite-search",        NULL };
74#endif
75static struct optname h_optname      = { "max-back-scroll",      NULL };
76static struct optname i_optname      = { "ignore-case",          NULL };
77static struct optname j_optname      = { "jump-target",          NULL };
78static struct optname J__optname     = { "status-column",        NULL };
79#if USERFILE
80static struct optname k_optname      = { "lesskey-file",         NULL };
81#endif
82static struct optname K__optname     = { "quit-on-intr",         NULL };
83static struct optname L__optname     = { "no-lessopen",          NULL };
84static struct optname m_optname      = { "long-prompt",          NULL };
85static struct optname n_optname      = { "line-numbers",         NULL };
86#if LOGFILE
87static struct optname o_optname      = { "log-file",             NULL };
88static struct optname O__optname     = { "LOG-FILE",             NULL };
89#endif
90static struct optname p_optname      = { "pattern",              NULL };
91static struct optname P__optname     = { "prompt",               NULL };
92static struct optname q2_optname     = { "silent",               NULL };
93static struct optname q_optname      = { "quiet",                &q2_optname };
94static struct optname r_optname      = { "raw-control-chars",    NULL };
95static struct optname s_optname      = { "squeeze-blank-lines",  NULL };
96static struct optname S__optname     = { "chop-long-lines",      NULL };
97#if TAGS
98static struct optname t_optname      = { "tag",                  NULL };
99static struct optname T__optname     = { "tag-file",             NULL };
100#endif
101static struct optname u_optname      = { "underline-special",    NULL };
102static struct optname V__optname     = { "version",              NULL };
103static struct optname w_optname      = { "hilite-unread",        NULL };
104static struct optname x_optname      = { "tabs",                 NULL };
105static struct optname X__optname     = { "no-init",              NULL };
106static struct optname y_optname      = { "max-forw-scroll",      NULL };
107static struct optname z_optname      = { "window",               NULL };
108static struct optname quote_optname  = { "quotes",               NULL };
109static struct optname tilde_optname  = { "tilde",                NULL };
110static struct optname query_optname  = { "help",                 NULL };
111static struct optname pound_optname  = { "shift",                NULL };
112static struct optname keypad_optname = { "no-keypad",            NULL };
113
114
115/*
116 * Table of all options and their semantics.
117 *
118 * For BOOL and TRIPLE options, odesc[0], odesc[1], odesc[2] are
119 * the description of the option when set to 0, 1 or 2, respectively.
120 * For NUMBER options, odesc[0] is the prompt to use when entering
121 * a new value, and odesc[1] is the description, which should contain
122 * one %d which is replaced by the value of the number.
123 * For STRING options, odesc[0] is the prompt to use when entering
124 * a new value, and odesc[1], if not NULL, is the set of characters
125 * that are valid in the string.
126 */
127static struct loption option[] =
128{
129	{ 'a', &a_optname,
130		BOOL, OPT_OFF, &how_search, NULL,
131		{
132			"Search includes displayed screen",
133			"Search skips displayed screen",
134			NULL
135		}
136	},
137
138	{ 'b', &b_optname,
139		NUMBER|INIT_HANDLER, 64, &bufspace, opt_b,
140		{
141			"Max buffer space per file (K): ",
142			"Max buffer space per file: %dK",
143			NULL
144		}
145	},
146	{ 'B', &B__optname,
147		BOOL, OPT_ON, &autobuf, NULL,
148		{
149			"Don't automatically allocate buffers",
150			"Automatically allocate buffers when needed",
151			NULL
152		}
153	},
154	{ 'c', &c_optname,
155		TRIPLE, OPT_OFF, &top_scroll, NULL,
156		{
157			"Repaint by scrolling from bottom of screen",
158			"Repaint by clearing each line",
159			"Repaint by painting from top of screen"
160		}
161	},
162	{ 'd', &d_optname,
163		BOOL|NO_TOGGLE, OPT_OFF, &know_dumb, NULL,
164		{
165			"Assume intelligent terminal",
166			"Assume dumb terminal",
167			NULL
168		}
169	},
170#if MSDOS_COMPILER
171	{ 'D', &D__optname,
172		STRING|REPAINT|NO_QUERY, 0, NULL, opt_D,
173		{
174			"color desc: ",
175			"Ddknsu0123456789.",
176			NULL
177		}
178	},
179#endif
180	{ 'e', &e_optname,
181		TRIPLE, OPT_OFF, &quit_at_eof, NULL,
182		{
183			"Don't quit at end-of-file",
184			"Quit at end-of-file",
185			"Quit immediately at end-of-file"
186		}
187	},
188	{ 'f', &f_optname,
189		BOOL, OPT_OFF, &force_open, NULL,
190		{
191			"Open only regular files",
192			"Open even non-regular files",
193			NULL
194		}
195	},
196	{ 'F', &F__optname,
197		BOOL, OPT_OFF, &quit_if_one_screen, NULL,
198		{
199			"Don't quit if end-of-file on first screen",
200			"Quit if end-of-file on first screen",
201			NULL
202		}
203	},
204#if HILITE_SEARCH
205	{ 'g', &g_optname,
206		TRIPLE|HL_REPAINT, OPT_ONPLUS, &hilite_search, NULL,
207		{
208			"Don't highlight search matches",
209			"Highlight matches for previous search only",
210			"Highlight all matches for previous search pattern",
211		}
212	},
213#endif
214	{ 'h', &h_optname,
215		NUMBER, -1, &back_scroll, NULL,
216		{
217			"Backwards scroll limit: ",
218			"Backwards scroll limit is %d lines",
219			NULL
220		}
221	},
222	{ 'i', &i_optname,
223		TRIPLE|HL_REPAINT, OPT_OFF, &caseless, opt_i,
224		{
225			"Case is significant in searches",
226			"Ignore case in searches",
227			"Ignore case in searches and in patterns"
228		}
229	},
230	{ 'j', &j_optname,
231		NUMBER, 1, &jump_sline, NULL,
232		{
233			"Target line: ",
234			"Position target at screen line %d",
235			NULL
236		}
237	},
238	{ 'J', &J__optname,
239		BOOL|REPAINT, OPT_OFF, &status_col, NULL,
240		{
241			"Don't display a status column",
242			"Display a status column",
243			NULL
244		}
245	},
246#if USERFILE
247	{ 'k', &k_optname,
248		STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_k,
249		{ NULL, NULL, NULL }
250	},
251#endif
252	{ 'K', &K__optname,
253		BOOL, OPT_OFF, &quit_on_intr, NULL,
254		{
255			"Interrupt (ctrl-C) returns to prompt",
256			"Interrupt (ctrl-C) exits less",
257			NULL
258		}
259	},
260	{ 'l', NULL,
261		STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_l,
262		{ NULL, NULL, NULL }
263	},
264	{ 'L', &L__optname,
265		BOOL, OPT_ON, &use_lessopen, NULL,
266		{
267			"Don't use the LESSOPEN filter",
268			"Use the LESSOPEN filter",
269			NULL
270		}
271	},
272	{ 'm', &m_optname,
273		TRIPLE, OPT_OFF, &pr_type, NULL,
274		{
275			"Short prompt",
276			"Medium prompt",
277			"Long prompt"
278		}
279	},
280	{ 'n', &n_optname,
281		TRIPLE|REPAINT, OPT_ON, &linenums, NULL,
282		{
283			"Don't use line numbers",
284			"Use line numbers",
285			"Constantly display line numbers"
286		}
287	},
288#if LOGFILE
289	{ 'o', &o_optname,
290		STRING, 0, NULL, opt_o,
291		{ "log file: ", NULL, NULL }
292	},
293	{ 'O', &O__optname,
294		STRING, 0, NULL, opt__O,
295		{ "Log file: ", NULL, NULL }
296	},
297#endif
298	{ 'p', &p_optname,
299		STRING|NO_TOGGLE|NO_QUERY, 0, NULL, opt_p,
300		{ NULL, NULL, NULL }
301	},
302	{ 'P', &P__optname,
303		STRING, 0, NULL, opt__P,
304		{ "prompt: ", NULL, NULL }
305	},
306	{ 'q', &q_optname,
307		TRIPLE, OPT_OFF, &quiet, NULL,
308		{
309			"Ring the bell for errors AND at eof/bof",
310			"Ring the bell for errors but not at eof/bof",
311			"Never ring the bell"
312		}
313	},
314	{ 'r', &r_optname,
315		TRIPLE|REPAINT, OPT_OFF, &ctldisp, NULL,
316		{
317			"Display control characters as ^X",
318			"Display control characters directly",
319			"Display control characters directly, processing ANSI sequences"
320		}
321	},
322	{ 's', &s_optname,
323		BOOL|REPAINT, OPT_OFF, &squeeze, NULL,
324		{
325			"Display all blank lines",
326			"Squeeze multiple blank lines",
327			NULL
328		}
329	},
330	{ 'S', &S__optname,
331		BOOL|REPAINT, OPT_OFF, &chopline, NULL,
332		{
333			"Fold long lines",
334			"Chop long lines",
335			NULL
336		}
337	},
338#if TAGS
339	{ 't', &t_optname,
340		STRING|NO_QUERY, 0, NULL, opt_t,
341		{ "tag: ", NULL, NULL }
342	},
343	{ 'T', &T__optname,
344		STRING, 0, NULL, opt__T,
345		{ "tags file: ", NULL, NULL }
346	},
347#endif
348	{ 'u', &u_optname,
349		TRIPLE|REPAINT, OPT_OFF, &bs_mode, NULL,
350		{
351			"Display underlined text in underline mode",
352			"Backspaces cause overstrike",
353			"Print backspace as ^H"
354		}
355	},
356	{ 'V', &V__optname,
357		NOVAR, 0, NULL, opt__V,
358		{ NULL, NULL, NULL }
359	},
360	{ 'w', &w_optname,
361		TRIPLE|REPAINT, OPT_OFF, &show_attn, NULL,
362		{
363			"Don't highlight first unread line",
364			"Highlight first unread line after forward-screen",
365			"Highlight first unread line after any forward movement",
366		}
367	},
368	{ 'x', &x_optname,
369		STRING|REPAINT, 0, NULL, opt_x,
370		{
371			"Tab stops: ",
372			"0123456789,",
373			NULL
374		}
375	},
376	{ 'X', &X__optname,
377		BOOL|NO_TOGGLE, OPT_OFF, &no_init, NULL,
378		{
379			"Send init/deinit strings to terminal",
380			"Don't use init/deinit strings",
381			NULL
382		}
383	},
384	{ 'y', &y_optname,
385		NUMBER, -1, &forw_scroll, NULL,
386		{
387			"Forward scroll limit: ",
388			"Forward scroll limit is %d lines",
389			NULL
390		}
391	},
392	{ 'z', &z_optname,
393		NUMBER, -1, &swindow, NULL,
394		{
395			"Scroll window size: ",
396			"Scroll window size is %d lines",
397			NULL
398		}
399	},
400	{ '"', &quote_optname,
401		STRING, 0, NULL, opt_quote,
402		{ "quotes: ", NULL, NULL }
403	},
404	{ '~', &tilde_optname,
405		BOOL|REPAINT, OPT_ON, &twiddle, NULL,
406		{
407			"Don't show tildes after end of file",
408			"Show tildes after end of file",
409			NULL
410		}
411	},
412	{ '?', &query_optname,
413		NOVAR, 0, NULL, opt_query,
414		{ NULL, NULL, NULL }
415	},
416	{ '#', &pound_optname,
417		NUMBER, 0, &shift_count, NULL,
418		{
419			"Horizontal shift: ",
420			"Horizontal shift %d positions",
421			NULL
422		}
423	},
424	{ '.', &keypad_optname,
425		BOOL|NO_TOGGLE, OPT_OFF, &no_keypad, NULL,
426		{
427			"Use keypad mode",
428			"Don't use keypad mode",
429			NULL
430		}
431	},
432	{ '\0', NULL, NOVAR, 0, NULL, NULL, { NULL, NULL, NULL } }
433};
434
435
436/*
437 * Initialize each option to its default value.
438 */
439	public void
440init_option()
441{
442	register struct loption *o;
443	char *p;
444
445	p = lgetenv("LESS_IS_MORE");
446	if (p != NULL && *p != '\0')
447		less_is_more = 1;
448
449	for (o = option;  o->oletter != '\0';  o++)
450	{
451		/*
452		 * Set each variable to its default.
453		 */
454		if (o->ovar != NULL)
455			*(o->ovar) = o->odefault;
456		if (o->otype & INIT_HANDLER)
457			(*(o->ofunc))(INIT, (char *) NULL);
458	}
459}
460
461/*
462 * Find an option in the option table, given its option letter.
463 */
464	public struct loption *
465findopt(c)
466	int c;
467{
468	register struct loption *o;
469
470	for (o = option;  o->oletter != '\0';  o++)
471	{
472		if (o->oletter == c)
473			return (o);
474		if ((o->otype & TRIPLE) && ASCII_TO_UPPER(o->oletter) == c)
475			return (o);
476	}
477	return (NULL);
478}
479
480/*
481 *
482 */
483	static int
484is_optchar(c)
485	char c;
486{
487	if (ASCII_IS_UPPER(c))
488		return 1;
489	if (ASCII_IS_LOWER(c))
490		return 1;
491	if (c == '-')
492		return 1;
493	return 0;
494}
495
496/*
497 * Find an option in the option table, given its option name.
498 * p_optname is the (possibly partial) name to look for, and
499 * is updated to point after the matched name.
500 * p_oname if non-NULL is set to point to the full option name.
501 */
502	public struct loption *
503findopt_name(p_optname, p_oname, p_err)
504	char **p_optname;
505	char **p_oname;
506	int *p_err;
507{
508	char *optname = *p_optname;
509	register struct loption *o;
510	register struct optname *oname;
511	register int len;
512	int uppercase;
513	struct loption *maxo = NULL;
514	struct optname *maxoname = NULL;
515	int maxlen = 0;
516	int ambig = 0;
517	int exact = 0;
518
519	/*
520	 * Check all options.
521	 */
522	for (o = option;  o->oletter != '\0';  o++)
523	{
524		/*
525		 * Check all names for this option.
526		 */
527		for (oname = o->onames;  oname != NULL;  oname = oname->onext)
528		{
529			/*
530			 * Try normal match first (uppercase == 0),
531			 * then, then if it's a TRIPLE option,
532			 * try uppercase match (uppercase == 1).
533			 */
534			for (uppercase = 0;  uppercase <= 1;  uppercase++)
535			{
536				len = sprefix(optname, oname->oname, uppercase);
537				if (len <= 0 || is_optchar(optname[len]))
538				{
539					/*
540					 * We didn't use all of the option name.
541					 */
542					continue;
543				}
544				if (!exact && len == maxlen)
545					/*
546					 * Already had a partial match,
547					 * and now there's another one that
548					 * matches the same length.
549					 */
550					ambig = 1;
551				else if (len > maxlen)
552				{
553					/*
554					 * Found a better match than
555					 * the one we had.
556					 */
557					maxo = o;
558					maxoname = oname;
559					maxlen = len;
560					ambig = 0;
561					exact = (len == (int)strlen(oname->oname));
562				}
563				if (!(o->otype & TRIPLE))
564					break;
565			}
566		}
567	}
568	if (ambig)
569	{
570		/*
571		 * Name matched more than one option.
572		 */
573		if (p_err != NULL)
574			*p_err = OPT_AMBIG;
575		return (NULL);
576	}
577	*p_optname = optname + maxlen;
578	if (p_oname != NULL)
579		*p_oname = maxoname == NULL ? NULL : maxoname->oname;
580	return (maxo);
581}
582