xref: /freebsd/contrib/less/lesskey.c (revision 82431678fce5c893ef9c7418ad6d998ad4187de6)
1 /*
2  * Copyright (C) 1984-2008  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  *	lesskey [-o output] [input]
14  *
15  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
16  *
17  *	Make a .less file.
18  *	If no input file is specified, standard input is used.
19  *	If no output file is specified, $HOME/.less is used.
20  *
21  *	The .less file is used to specify (to "less") user-defined
22  *	key bindings.  Basically any sequence of 1 to MAX_CMDLEN
23  *	keystrokes may be bound to an existing less function.
24  *
25  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
26  *
27  *	The input file is an ascii file consisting of a
28  *	sequence of lines of the form:
29  *		string <whitespace> action [chars] <newline>
30  *
31  *	"string" is a sequence of command characters which form
32  *		the new user-defined command.  The command
33  *		characters may be:
34  *		1. The actual character itself.
35  *		2. A character preceded by ^ to specify a
36  *		   control character (e.g. ^X means control-X).
37  *		3. A backslash followed by one to three octal digits
38  *		   to specify a character by its octal value.
39  *		4. A backslash followed by b, e, n, r or t
40  *		   to specify \b, ESC, \n, \r or \t, respectively.
41  *		5. Any character (other than those mentioned above) preceded
42  *		   by a \ to specify the character itself (characters which
43  *		   must be preceded by \ include ^, \, and whitespace.
44  *	"action" is the name of a "less" action, from the table below.
45  *	"chars" is an optional sequence of characters which is treated
46  *		as keyboard input after the command is executed.
47  *
48  *	Blank lines and lines which start with # are ignored,
49  *	except for the special control lines:
50  *		#command	Signals the beginning of the command
51  *				keys section.
52  *		#line-edit	Signals the beginning of the line-editing
53  *				keys section.
54  *		#env		Signals the beginning of the environment
55  *				variable section.
56  *		#stop		Stops command parsing in less;
57  *				causes all default keys to be disabled.
58  *
59  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
60  *
61  *	The output file is a non-ascii file, consisting of a header,
62  *	one or more sections, and a trailer.
63  *	Each section begins with a section header, a section length word
64  *	and the section data.  Normally there are three sections:
65  *		CMD_SECTION	Definition of command keys.
66  *		EDIT_SECTION	Definition of editing keys.
67  *		END_SECTION	A special section header, with no
68  *				length word or section data.
69  *
70  *	Section data consists of zero or more byte sequences of the form:
71  *		string <0> <action>
72  *	or
73  *		string <0> <action|A_EXTRA> chars <0>
74  *
75  *	"string" is the command string.
76  *	"<0>" is one null byte.
77  *	"<action>" is one byte containing the action code (the A_xxx value).
78  *	If action is ORed with A_EXTRA, the action byte is followed
79  *		by the null-terminated "chars" string.
80  *
81  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
82  */
83 
84 #include "less.h"
85 #include "lesskey.h"
86 #include "cmd.h"
87 
88 struct cmdname
89 {
90 	char *cn_name;
91 	int cn_action;
92 };
93 
94 struct cmdname cmdnames[] =
95 {
96 	{ "back-bracket",         A_B_BRACKET },
97 	{ "back-line",            A_B_LINE },
98 	{ "back-line-force",      A_BF_LINE },
99 	{ "back-screen",          A_B_SCREEN },
100 	{ "back-scroll",          A_B_SCROLL },
101 	{ "back-search",          A_B_SEARCH },
102 	{ "back-window",          A_B_WINDOW },
103 	{ "debug",                A_DEBUG },
104 	{ "digit",                A_DIGIT },
105 	{ "display-flag",         A_DISP_OPTION },
106 	{ "display-option",       A_DISP_OPTION },
107 	{ "end",                  A_GOEND },
108 	{ "examine",              A_EXAMINE },
109 	{ "filter",               A_FILTER },
110 	{ "first-cmd",            A_FIRSTCMD },
111 	{ "firstcmd",             A_FIRSTCMD },
112 	{ "flush-repaint",        A_FREPAINT },
113 	{ "forw-bracket",         A_F_BRACKET },
114 	{ "forw-forever",         A_F_FOREVER },
115 	{ "forw-line",            A_F_LINE },
116 	{ "forw-line-force",      A_FF_LINE },
117 	{ "forw-screen",          A_F_SCREEN },
118 	{ "forw-screen-force",    A_FF_SCREEN },
119 	{ "forw-scroll",          A_F_SCROLL },
120 	{ "forw-search",          A_F_SEARCH },
121 	{ "forw-window",          A_F_WINDOW },
122 	{ "goto-end",             A_GOEND },
123 	{ "goto-line",            A_GOLINE },
124 	{ "goto-mark",            A_GOMARK },
125 	{ "help",                 A_HELP },
126 	{ "index-file",           A_INDEX_FILE },
127 	{ "invalid",              A_UINVALID },
128 	{ "left-scroll",          A_LSHIFT },
129 	{ "next-file",            A_NEXT_FILE },
130 	{ "next-tag",             A_NEXT_TAG },
131 	{ "noaction",             A_NOACTION },
132 	{ "percent",              A_PERCENT },
133 	{ "pipe",                 A_PIPE },
134 	{ "prev-file",            A_PREV_FILE },
135 	{ "prev-tag",             A_PREV_TAG },
136 	{ "quit",                 A_QUIT },
137 	{ "remove-file",          A_REMOVE_FILE },
138 	{ "repaint",              A_REPAINT },
139 	{ "repaint-flush",        A_FREPAINT },
140 	{ "repeat-search",        A_AGAIN_SEARCH },
141 	{ "repeat-search-all",    A_T_AGAIN_SEARCH },
142 	{ "reverse-search",       A_REVERSE_SEARCH },
143 	{ "reverse-search-all",   A_T_REVERSE_SEARCH },
144 	{ "right-scroll",         A_RSHIFT },
145 	{ "set-mark",             A_SETMARK },
146 	{ "shell",                A_SHELL },
147 	{ "status",               A_STAT },
148 	{ "toggle-flag",          A_OPT_TOGGLE },
149 	{ "toggle-option",        A_OPT_TOGGLE },
150 	{ "undo-hilite",          A_UNDO_SEARCH },
151 	{ "version",              A_VERSION },
152 	{ "visual",               A_VISUAL },
153 	{ NULL,   0 }
154 };
155 
156 struct cmdname editnames[] =
157 {
158 	{ "back-complete",	EC_B_COMPLETE },
159 	{ "backspace",		EC_BACKSPACE },
160 	{ "delete",		EC_DELETE },
161 	{ "down",		EC_DOWN },
162 	{ "end",		EC_END },
163 	{ "expand",		EC_EXPAND },
164 	{ "forw-complete",	EC_F_COMPLETE },
165 	{ "home",		EC_HOME },
166 	{ "insert",		EC_INSERT },
167 	{ "invalid",		EC_UINVALID },
168 	{ "kill-line",		EC_LINEKILL },
169 	{ "left",		EC_LEFT },
170 	{ "literal",		EC_LITERAL },
171 	{ "right",		EC_RIGHT },
172 	{ "up",			EC_UP },
173 	{ "word-backspace",	EC_W_BACKSPACE },
174 	{ "word-delete",	EC_W_DELETE },
175 	{ "word-left",		EC_W_LEFT },
176 	{ "word-right",		EC_W_RIGHT },
177 	{ NULL, 0 }
178 };
179 
180 struct table
181 {
182 	struct cmdname *names;
183 	char *pbuffer;
184 	char buffer[MAX_USERCMD];
185 };
186 
187 struct table cmdtable;
188 struct table edittable;
189 struct table vartable;
190 struct table *currtable = &cmdtable;
191 
192 char fileheader[] = {
193 	C0_LESSKEY_MAGIC,
194 	C1_LESSKEY_MAGIC,
195 	C2_LESSKEY_MAGIC,
196 	C3_LESSKEY_MAGIC
197 };
198 char filetrailer[] = {
199 	C0_END_LESSKEY_MAGIC,
200 	C1_END_LESSKEY_MAGIC,
201 	C2_END_LESSKEY_MAGIC
202 };
203 char cmdsection[1] =	{ CMD_SECTION };
204 char editsection[1] =	{ EDIT_SECTION };
205 char varsection[1] =	{ VAR_SECTION };
206 char endsection[1] =	{ END_SECTION };
207 
208 char *infile = NULL;
209 char *outfile = NULL ;
210 
211 int linenum;
212 int errors;
213 
214 extern char version[];
215 
216 	void
217 usage()
218 {
219 	fprintf(stderr, "usage: lesskey [-o output] [input]\n");
220 	exit(1);
221 }
222 
223 	char *
224 mkpathname(dirname, filename)
225 	char *dirname;
226 	char *filename;
227 {
228 	char *pathname;
229 
230 	pathname = calloc(strlen(dirname) + strlen(filename) + 2, sizeof(char));
231 	strcpy(pathname, dirname);
232 	strcat(pathname, PATHNAME_SEP);
233 	strcat(pathname, filename);
234 	return (pathname);
235 }
236 
237 /*
238  * Figure out the name of a default file (in the user's HOME directory).
239  */
240 	char *
241 homefile(filename)
242 	char *filename;
243 {
244 	char *p;
245 	char *pathname;
246 
247 	if ((p = getenv("HOME")) != NULL && *p != '\0')
248 		pathname = mkpathname(p, filename);
249 #if OS2
250 	else if ((p = getenv("INIT")) != NULL && *p != '\0')
251 		pathname = mkpathname(p, filename);
252 #endif
253 	else
254 	{
255 		fprintf(stderr, "cannot find $HOME - using current directory\n");
256 		pathname = mkpathname(".", filename);
257 	}
258 	return (pathname);
259 }
260 
261 /*
262  * Parse command line arguments.
263  */
264 	void
265 parse_args(argc, argv)
266 	int argc;
267 	char **argv;
268 {
269 	char *arg;
270 
271 	outfile = NULL;
272 	while (--argc > 0)
273 	{
274 		arg = *++argv;
275 		if (arg[0] != '-')
276 			/* Arg does not start with "-"; it's not an option. */
277 			break;
278 		if (arg[1] == '\0')
279 			/* "-" means standard input. */
280 			break;
281 		if (arg[1] == '-' && arg[2] == '\0')
282 		{
283 			/* "--" means end of options. */
284 			argc--;
285 			argv++;
286 			break;
287 		}
288 		switch (arg[1])
289 		{
290 		case '-':
291 			if (strncmp(arg, "--output", 8) == 0)
292 			{
293 				if (arg[8] == '\0')
294 					outfile = &arg[8];
295 				else if (arg[8] == '=')
296 					outfile = &arg[9];
297 				else
298 					usage();
299 				goto opt_o;
300 			}
301 			if (strcmp(arg, "--version") == 0)
302 			{
303 				goto opt_V;
304 			}
305 			usage();
306 			break;
307 		case 'o':
308 			outfile = &argv[0][2];
309 		opt_o:
310 			if (*outfile == '\0')
311 			{
312 				if (--argc <= 0)
313 					usage();
314 				outfile = *(++argv);
315 			}
316 			break;
317 		case 'V':
318 		opt_V:
319 			printf("lesskey  version %s\n", version);
320 			exit(0);
321 		default:
322 			usage();
323 		}
324 	}
325 	if (argc > 1)
326 		usage();
327 	/*
328 	 * Open the input file, or use DEF_LESSKEYINFILE if none specified.
329 	 */
330 	if (argc > 0)
331 		infile = *argv;
332 	else
333 		infile = homefile(DEF_LESSKEYINFILE);
334 }
335 
336 /*
337  * Initialize data structures.
338  */
339 	void
340 init_tables()
341 {
342 	cmdtable.names = cmdnames;
343 	cmdtable.pbuffer = cmdtable.buffer;
344 
345 	edittable.names = editnames;
346 	edittable.pbuffer = edittable.buffer;
347 
348 	vartable.names = NULL;
349 	vartable.pbuffer = vartable.buffer;
350 }
351 
352 /*
353  * Parse one character of a string.
354  */
355 	char *
356 tstr(pp, xlate)
357 	char **pp;
358 	int xlate;
359 {
360 	register char *p;
361 	register char ch;
362 	register int i;
363 	static char buf[10];
364 	static char tstr_control_k[] =
365 		{ SK_SPECIAL_KEY, SK_CONTROL_K, 6, 1, 1, 1, '\0' };
366 
367 	p = *pp;
368 	switch (*p)
369 	{
370 	case '\\':
371 		++p;
372 		switch (*p)
373 		{
374 		case '0': case '1': case '2': case '3':
375 		case '4': case '5': case '6': case '7':
376 			/*
377 			 * Parse an octal number.
378 			 */
379 			ch = 0;
380 			i = 0;
381 			do
382 				ch = 8*ch + (*p - '0');
383 			while (*++p >= '0' && *p <= '7' && ++i < 3);
384 			*pp = p;
385 			if (xlate && ch == CONTROL('K'))
386 				return tstr_control_k;
387 			buf[0] = ch;
388 			buf[1] = '\0';
389 			return (buf);
390 		case 'b':
391 			*pp = p+1;
392 			return ("\b");
393 		case 'e':
394 			*pp = p+1;
395 			buf[0] = ESC;
396 			buf[1] = '\0';
397 			return (buf);
398 		case 'n':
399 			*pp = p+1;
400 			return ("\n");
401 		case 'r':
402 			*pp = p+1;
403 			return ("\r");
404 		case 't':
405 			*pp = p+1;
406 			return ("\t");
407 		case 'k':
408 			if (xlate)
409 			{
410 				switch (*++p)
411 				{
412 				case 'u': ch = SK_UP_ARROW; break;
413 				case 'd': ch = SK_DOWN_ARROW; break;
414 				case 'r': ch = SK_RIGHT_ARROW; break;
415 				case 'l': ch = SK_LEFT_ARROW; break;
416 				case 'U': ch = SK_PAGE_UP; break;
417 				case 'D': ch = SK_PAGE_DOWN; break;
418 				case 'h': ch = SK_HOME; break;
419 				case 'e': ch = SK_END; break;
420 				case 'x': ch = SK_DELETE; break;
421 				default:
422 					error("illegal char after \\k");
423 					*pp = p+1;
424 					return ("");
425 				}
426 				*pp = p+1;
427 				buf[0] = SK_SPECIAL_KEY;
428 				buf[1] = ch;
429 				buf[2] = 6;
430 				buf[3] = 1;
431 				buf[4] = 1;
432 				buf[5] = 1;
433 				buf[6] = '\0';
434 				return (buf);
435 			}
436 			/* FALLTHRU */
437 		default:
438 			/*
439 			 * Backslash followed by any other char
440 			 * just means that char.
441 			 */
442 			*pp = p+1;
443 			buf[0] = *p;
444 			buf[1] = '\0';
445 			if (xlate && buf[0] == CONTROL('K'))
446 				return tstr_control_k;
447 			return (buf);
448 		}
449 	case '^':
450 		/*
451 		 * Carat means CONTROL.
452 		 */
453 		*pp = p+2;
454 		buf[0] = CONTROL(p[1]);
455 		buf[1] = '\0';
456 		if (buf[0] == CONTROL('K'))
457 			return tstr_control_k;
458 		return (buf);
459 	}
460 	*pp = p+1;
461 	buf[0] = *p;
462 	buf[1] = '\0';
463 	if (xlate && buf[0] == CONTROL('K'))
464 		return tstr_control_k;
465 	return (buf);
466 }
467 
468 /*
469  * Skip leading spaces in a string.
470  */
471 	public char *
472 skipsp(s)
473 	register char *s;
474 {
475 	while (*s == ' ' || *s == '\t')
476 		s++;
477 	return (s);
478 }
479 
480 /*
481  * Skip non-space characters in a string.
482  */
483 	public char *
484 skipnsp(s)
485 	register char *s;
486 {
487 	while (*s != '\0' && *s != ' ' && *s != '\t')
488 		s++;
489 	return (s);
490 }
491 
492 /*
493  * Clean up an input line:
494  * strip off the trailing newline & any trailing # comment.
495  */
496 	char *
497 clean_line(s)
498 	char *s;
499 {
500 	register int i;
501 
502 	s = skipsp(s);
503 	for (i = 0;  s[i] != '\n' && s[i] != '\r' && s[i] != '\0';  i++)
504 		if (s[i] == '#' && (i == 0 || s[i-1] != '\\'))
505 			break;
506 	s[i] = '\0';
507 	return (s);
508 }
509 
510 /*
511  * Add a byte to the output command table.
512  */
513 	void
514 add_cmd_char(c)
515 	int c;
516 {
517 	if (currtable->pbuffer >= currtable->buffer + MAX_USERCMD)
518 	{
519 		error("too many commands");
520 		exit(1);
521 	}
522 	*(currtable->pbuffer)++ = c;
523 }
524 
525 /*
526  * Add a string to the output command table.
527  */
528 	void
529 add_cmd_str(s)
530 	char *s;
531 {
532 	for ( ;  *s != '\0';  s++)
533 		add_cmd_char(*s);
534 }
535 
536 /*
537  * See if we have a special "control" line.
538  */
539 	int
540 control_line(s)
541 	char *s;
542 {
543 #define	PREFIX(str,pat)	(strncmp(str,pat,strlen(pat)) == 0)
544 
545 	if (PREFIX(s, "#line-edit"))
546 	{
547 		currtable = &edittable;
548 		return (1);
549 	}
550 	if (PREFIX(s, "#command"))
551 	{
552 		currtable = &cmdtable;
553 		return (1);
554 	}
555 	if (PREFIX(s, "#env"))
556 	{
557 		currtable = &vartable;
558 		return (1);
559 	}
560 	if (PREFIX(s, "#stop"))
561 	{
562 		add_cmd_char('\0');
563 		add_cmd_char(A_END_LIST);
564 		return (1);
565 	}
566 	return (0);
567 }
568 
569 /*
570  * Output some bytes.
571  */
572 	void
573 fputbytes(fd, buf, len)
574 	FILE *fd;
575 	char *buf;
576 	int len;
577 {
578 	while (len-- > 0)
579 	{
580 		fwrite(buf, sizeof(char), 1, fd);
581 		buf++;
582 	}
583 }
584 
585 /*
586  * Output an integer, in special KRADIX form.
587  */
588 	void
589 fputint(fd, val)
590 	FILE *fd;
591 	unsigned int val;
592 {
593 	char c;
594 
595 	if (val >= KRADIX*KRADIX)
596 	{
597 		fprintf(stderr, "error: integer too big (%d > %d)\n",
598 			val, KRADIX*KRADIX);
599 		exit(1);
600 	}
601 	c = val % KRADIX;
602 	fwrite(&c, sizeof(char), 1, fd);
603 	c = val / KRADIX;
604 	fwrite(&c, sizeof(char), 1, fd);
605 }
606 
607 /*
608  * Find an action, given the name of the action.
609  */
610 	int
611 findaction(actname)
612 	char *actname;
613 {
614 	int i;
615 
616 	for (i = 0;  currtable->names[i].cn_name != NULL;  i++)
617 		if (strcmp(currtable->names[i].cn_name, actname) == 0)
618 			return (currtable->names[i].cn_action);
619 	error("unknown action");
620 	return (A_INVALID);
621 }
622 
623 	void
624 error(s)
625 	char *s;
626 {
627 	fprintf(stderr, "line %d: %s\n", linenum, s);
628 	errors++;
629 }
630 
631 
632 	void
633 parse_cmdline(p)
634 	char *p;
635 {
636 	int cmdlen;
637 	char *actname;
638 	int action;
639 	char *s;
640 	char c;
641 
642 	/*
643 	 * Parse the command string and store it in the current table.
644 	 */
645 	cmdlen = 0;
646 	do
647 	{
648 		s = tstr(&p, 1);
649 		cmdlen += strlen(s);
650 		if (cmdlen > MAX_CMDLEN)
651 			error("command too long");
652 		else
653 			add_cmd_str(s);
654 	} while (*p != ' ' && *p != '\t' && *p != '\0');
655 	/*
656 	 * Terminate the command string with a null byte.
657 	 */
658 	add_cmd_char('\0');
659 
660 	/*
661 	 * Skip white space between the command string
662 	 * and the action name.
663 	 * Terminate the action name with a null byte.
664 	 */
665 	p = skipsp(p);
666 	if (*p == '\0')
667 	{
668 		error("missing action");
669 		return;
670 	}
671 	actname = p;
672 	p = skipnsp(p);
673 	c = *p;
674 	*p = '\0';
675 
676 	/*
677 	 * Parse the action name and store it in the current table.
678 	 */
679 	action = findaction(actname);
680 
681 	/*
682 	 * See if an extra string follows the action name.
683 	 */
684 	*p = c;
685 	p = skipsp(p);
686 	if (*p == '\0')
687 	{
688 		add_cmd_char(action);
689 	} else
690 	{
691 		/*
692 		 * OR the special value A_EXTRA into the action byte.
693 		 * Put the extra string after the action byte.
694 		 */
695 		add_cmd_char(action | A_EXTRA);
696 		while (*p != '\0')
697 			add_cmd_str(tstr(&p, 0));
698 		add_cmd_char('\0');
699 	}
700 }
701 
702 	void
703 parse_varline(p)
704 	char *p;
705 {
706 	char *s;
707 
708 	do
709 	{
710 		s = tstr(&p, 0);
711 		add_cmd_str(s);
712 	} while (*p != ' ' && *p != '\t' && *p != '=' && *p != '\0');
713 	/*
714 	 * Terminate the variable name with a null byte.
715 	 */
716 	add_cmd_char('\0');
717 
718 	p = skipsp(p);
719 	if (*p++ != '=')
720 	{
721 		error("missing =");
722 		return;
723 	}
724 
725 	add_cmd_char(EV_OK|A_EXTRA);
726 
727 	p = skipsp(p);
728 	while (*p != '\0')
729 	{
730 		s = tstr(&p, 0);
731 		add_cmd_str(s);
732 	}
733 	add_cmd_char('\0');
734 }
735 
736 /*
737  * Parse a line from the lesskey file.
738  */
739 	void
740 parse_line(line)
741 	char *line;
742 {
743 	char *p;
744 
745 	/*
746 	 * See if it is a control line.
747 	 */
748 	if (control_line(line))
749 		return;
750 	/*
751 	 * Skip leading white space.
752 	 * Replace the final newline with a null byte.
753 	 * Ignore blank lines and comments.
754 	 */
755 	p = clean_line(line);
756 	if (*p == '\0')
757 		return;
758 
759 	if (currtable == &vartable)
760 		parse_varline(p);
761 	else
762 		parse_cmdline(p);
763 }
764 
765 	int
766 main(argc, argv)
767 	int argc;
768 	char *argv[];
769 {
770 	FILE *desc;
771 	FILE *out;
772 	char line[1024];
773 
774 #ifdef WIN32
775 	if (getenv("HOME") == NULL)
776 	{
777 		/*
778 		 * If there is no HOME environment variable,
779 		 * try the concatenation of HOMEDRIVE + HOMEPATH.
780 		 */
781 		char *drive = getenv("HOMEDRIVE");
782 		char *path  = getenv("HOMEPATH");
783 		if (drive != NULL && path != NULL)
784 		{
785 			char *env = (char *) calloc(strlen(drive) +
786 					strlen(path) + 6, sizeof(char));
787 			strcpy(env, "HOME=");
788 			strcat(env, drive);
789 			strcat(env, path);
790 			putenv(env);
791 		}
792 	}
793 #endif /* WIN32 */
794 
795 	/*
796 	 * Process command line arguments.
797 	 */
798 	parse_args(argc, argv);
799 	init_tables();
800 
801 	/*
802 	 * Open the input file.
803 	 */
804 	if (strcmp(infile, "-") == 0)
805 		desc = stdin;
806 	else if ((desc = fopen(infile, "r")) == NULL)
807 	{
808 #if HAVE_PERROR
809 		perror(infile);
810 #else
811 		fprintf(stderr, "Cannot open %s\n", infile);
812 #endif
813 		usage();
814 	}
815 
816 	/*
817 	 * Read and parse the input file, one line at a time.
818 	 */
819 	errors = 0;
820 	linenum = 0;
821 	while (fgets(line, sizeof(line), desc) != NULL)
822 	{
823 		++linenum;
824 		parse_line(line);
825 	}
826 
827 	/*
828 	 * Write the output file.
829 	 * If no output file was specified, use "$HOME/.less"
830 	 */
831 	if (errors > 0)
832 	{
833 		fprintf(stderr, "%d errors; no output produced\n", errors);
834 		exit(1);
835 	}
836 
837 	if (outfile == NULL)
838 		outfile = getenv("LESSKEY");
839 	if (outfile == NULL)
840 		outfile = homefile(LESSKEYFILE);
841 	if ((out = fopen(outfile, "wb")) == NULL)
842 	{
843 #if HAVE_PERROR
844 		perror(outfile);
845 #else
846 		fprintf(stderr, "Cannot open %s\n", outfile);
847 #endif
848 		exit(1);
849 	}
850 
851 	/* File header */
852 	fputbytes(out, fileheader, sizeof(fileheader));
853 
854 	/* Command key section */
855 	fputbytes(out, cmdsection, sizeof(cmdsection));
856 	fputint(out, cmdtable.pbuffer - cmdtable.buffer);
857 	fputbytes(out, (char *)cmdtable.buffer, cmdtable.pbuffer-cmdtable.buffer);
858 	/* Edit key section */
859 	fputbytes(out, editsection, sizeof(editsection));
860 	fputint(out, edittable.pbuffer - edittable.buffer);
861 	fputbytes(out, (char *)edittable.buffer, edittable.pbuffer-edittable.buffer);
862 
863 	/* Environment variable section */
864 	fputbytes(out, varsection, sizeof(varsection));
865 	fputint(out, vartable.pbuffer - vartable.buffer);
866 	fputbytes(out, (char *)vartable.buffer, vartable.pbuffer-vartable.buffer);
867 
868 	/* File trailer */
869 	fputbytes(out, endsection, sizeof(endsection));
870 	fputbytes(out, filetrailer, sizeof(filetrailer));
871 	return (0);
872 }
873