xref: /openbsd-src/lib/libcurses/tinfo/comp_scan.c (revision 40ecf94db7fa4502a9387680c2502ce8909185e3)
1 /****************************************************************************
2  * Copyright (c) 1998,1999,2000 Free Software Foundation, Inc.              *
3  *                                                                          *
4  * Permission is hereby granted, free of charge, to any person obtaining a  *
5  * copy of this software and associated documentation files (the            *
6  * "Software"), to deal in the Software without restriction, including      *
7  * without limitation the rights to use, copy, modify, merge, publish,      *
8  * distribute, distribute with modifications, sublicense, and/or sell       *
9  * copies of the Software, and to permit persons to whom the Software is    *
10  * furnished to do so, subject to the following conditions:                 *
11  *                                                                          *
12  * The above copyright notice and this permission notice shall be included  *
13  * in all copies or substantial portions of the Software.                   *
14  *                                                                          *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
16  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
18  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
19  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
20  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
21  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
22  *                                                                          *
23  * Except as contained in this notice, the name(s) of the above copyright   *
24  * holders shall not be used in advertising or otherwise to promote the     *
25  * sale, use or other dealings in this Software without prior written       *
26  * authorization.                                                           *
27  ****************************************************************************/
28 
29 /****************************************************************************
30  *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
31  *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
32  ****************************************************************************/
33 
34 /*
35  *	comp_scan.c --- Lexical scanner for terminfo compiler.
36  *
37  *	_nc_reset_input()
38  *	_nc_get_token()
39  *	_nc_panic_mode()
40  *	int _nc_syntax;
41  *	int _nc_curr_line;
42  *	long _nc_curr_file_pos;
43  *	long _nc_comment_start;
44  *	long _nc_comment_end;
45  */
46 
47 #include <curses.priv.h>
48 
49 #include <ctype.h>
50 #include <term_entry.h>
51 #include <tic.h>
52 
53 MODULE_ID("$From: comp_scan.c,v 1.42 2000/04/01 19:08:36 tom Exp $")
54 
55 /*
56  * Maximum length of string capability we'll accept before raising an error.
57  * Yes, there is a real capability in /etc/termcap this long, an "is".
58  */
59 #define MAXCAPLEN	600
60 
61 #define iswhite(ch)	(ch == ' '  ||  ch == '\t')
62 
63 int _nc_syntax = 0;		/* termcap or terminfo? */
64 long _nc_curr_file_pos = 0;	/* file offset of current line */
65 long _nc_comment_start = 0;	/* start of comment range before name */
66 long _nc_comment_end = 0;	/* end of comment range before name */
67 long _nc_start_line = 0;	/* start line of current entry */
68 
69 /*****************************************************************************
70  *
71  * Token-grabbing machinery
72  *
73  *****************************************************************************/
74 
75 static bool first_column;	/* See 'next_char()' below */
76 static char separator;		/* capability separator */
77 static int pushtype;		/* type of pushback token */
78 static char pushname[MAX_NAME_SIZE + 1];
79 
80 static int last_char(void);
81 static int next_char(void);
82 static long stream_pos(void);
83 static bool end_of_stream(void);
84 static void push_back(char c);
85 
86 /* Assume we may be looking at a termcap-style continuation */
87 static inline int
88 eat_escaped_newline(int ch)
89 {
90     if (ch == '\\')
91 	while ((ch = next_char()) == '\n' || iswhite(ch))
92 	    continue;
93     return ch;
94 }
95 
96 /*
97  *	int
98  *	get_token()
99  *
100  *	Scans the input for the next token, storing the specifics in the
101  *	global structure 'curr_token' and returning one of the following:
102  *
103  *		NAMES		A line beginning in column 1.  'name'
104  *				will be set to point to everything up to but
105  *				not including the first separator on the line.
106  *		BOOLEAN		An entry consisting of a name followed by
107  *				a separator.  'name' will be set to point to
108  *				the name of the capability.
109  *		NUMBER		An entry of the form
110  *					name#digits,
111  *				'name' will be set to point to the capability
112  *				name and 'valnumber' to the number given.
113  *		STRING		An entry of the form
114  *					name=characters,
115  *				'name' is set to the capability name and
116  *				'valstring' to the string of characters, with
117  *				input translations done.
118  *		CANCEL		An entry of the form
119  *					name@,
120  *				'name' is set to the capability name and
121  *				'valnumber' to -1.
122  *		EOF		The end of the file has been reached.
123  *
124  *	A `separator' is either a comma or a semicolon, depending on whether
125  *	we are in termcap or terminfo mode.
126  *
127  */
128 
129 int
130 _nc_get_token(void)
131 {
132     static const char terminfo_punct[] = "@%&*!#";
133     long number;
134     int type;
135     int ch;
136     char *numchk;
137     char numbuf[80];
138     unsigned found;
139     static char buffer[MAX_ENTRY_SIZE];
140     char *ptr;
141     int dot_flag = FALSE;
142     long token_start;
143 
144     if (pushtype != NO_PUSHBACK) {
145 	int retval = pushtype;
146 
147 	_nc_set_type(pushname);
148 	DEBUG(3, ("pushed-back token: `%s', class %d",
149 		_nc_curr_token.tk_name, pushtype));
150 
151 	pushtype = NO_PUSHBACK;
152 	pushname[0] = '\0';
153 
154 	/* currtok wasn't altered by _nc_push_token() */
155 	return (retval);
156     }
157 
158     if (end_of_stream())
159 	return (EOF);
160 
161   start_token:
162     token_start = stream_pos();
163     while ((ch = next_char()) == '\n' || iswhite(ch))
164 	continue;
165 
166     ch = eat_escaped_newline(ch);
167 
168     if (ch == EOF)
169 	type = EOF;
170     else {
171 	/* if this is a termcap entry, skip a leading separator */
172 	if (separator == ':' && ch == ':')
173 	    ch = next_char();
174 
175 	if (ch == '.'
176 #ifdef NCURSES_EXT_FUNCS
177 	 && !_nc_disable_period
178 #endif
179 	) {
180 	    dot_flag = TRUE;
181 	    DEBUG(8, ("dot-flag set"));
182 
183 	    while ((ch = next_char()) == '.' || iswhite(ch))
184 		continue;
185 	}
186 
187 	if (ch == EOF) {
188 	    type = EOF;
189 	    goto end_of_token;
190 	}
191 
192 	/* have to make some punctuation chars legal for terminfo */
193 	if (!isalnum(ch)
194 #ifdef NCURSES_EXT_FUNCS
195 	 && !(ch == '.' && _nc_disable_period)
196 #endif
197 	 && !strchr(terminfo_punct, (char) ch)) {
198 	    _nc_warning("Illegal character (expected alphanumeric or %s) - %s",
199 		terminfo_punct, unctrl(ch));
200 	    _nc_panic_mode(separator);
201 	    goto start_token;
202 	}
203 
204 	ptr = buffer;
205 	*(ptr++) = ch;
206 
207 	if (first_column) {
208 	    char *desc;
209 
210 	    _nc_comment_start = token_start;
211 	    _nc_comment_end = _nc_curr_file_pos;
212 	    _nc_start_line = _nc_curr_line;
213 
214 	    _nc_syntax = ERR;
215 	    while ((ch = next_char()) != '\n') {
216 		if (ch == EOF)
217 		    _nc_err_abort("premature EOF");
218 		else if (ch == ':' && last_char() != ',') {
219 		    _nc_syntax = SYN_TERMCAP;
220 		    separator = ':';
221 		    break;
222 		} else if (ch == ',') {
223 		    _nc_syntax = SYN_TERMINFO;
224 		    separator = ',';
225 		    /*
226 		     * Fall-through here is not an accident.
227 		     * The idea is that if we see a comma, we
228 		     * figure this is terminfo unless we
229 		     * subsequently run into a colon -- but
230 		     * we don't stop looking for that colon until
231 		     * hitting a newline.  This allows commas to
232 		     * be embedded in description fields of
233 		     * either syntax.
234 		     */
235 		    /* FALLTHRU */
236 		} else
237 		    ch = eat_escaped_newline(ch);
238 
239 		*ptr++ = ch;
240 	    }
241 	    ptr[0] = '\0';
242 	    if (_nc_syntax == ERR) {
243 		/*
244 		 * Grrr...what we ought to do here is barf,
245 		 * complaining that the entry is malformed.
246 		 * But because a couple of name fields in the
247 		 * 8.2 termcap file end with |\, we just have
248 		 * to assume it's termcap syntax.
249 		 */
250 		_nc_syntax = SYN_TERMCAP;
251 		separator = ':';
252 	    } else if (_nc_syntax == SYN_TERMINFO) {
253 		/* throw away trailing /, *$/ */
254 		for (--ptr; iswhite(*ptr) || *ptr == ','; ptr--)
255 		    continue;
256 		ptr[1] = '\0';
257 	    }
258 
259 	    /*
260 	     * This is the soonest we have the terminal name
261 	     * fetched.  Set up for following warning messages.
262 	     */
263 	    ptr = strchr(buffer, '|');
264 	    if (ptr == (char *) NULL)
265 		ptr = buffer + strlen(buffer);
266 	    ch = *ptr;
267 	    *ptr = '\0';
268 	    _nc_set_type(buffer);
269 	    *ptr = ch;
270 
271 	    /*
272 	     * Compute the boundary between the aliases and the
273 	     * description field for syntax-checking purposes.
274 	     */
275 	    desc = strrchr(buffer, '|');
276 	    if (desc) {
277 		if (*desc == '\0')
278 		    _nc_warning("empty longname field");
279 		else if (strchr(desc, ' ') == (char *) NULL)
280 		    _nc_warning("older tic versions may treat the description field as an alias");
281 	    }
282 	    if (!desc)
283 		desc = buffer + strlen(buffer);
284 
285 	    /*
286 	     * Whitespace in a name field other than the long name
287 	     * can confuse rdist and some termcap tools.  Slashes
288 	     * are a no-no.  Other special characters can be
289 	     * dangerous due to shell expansion.
290 	     */
291 	    for (ptr = buffer; ptr < desc; ptr++) {
292 		if (isspace(*ptr)) {
293 		    _nc_warning("whitespace in name or alias field");
294 		    break;
295 		} else if (*ptr == '/') {
296 		    _nc_warning("slashes aren't allowed in names or aliases");
297 		    break;
298 		} else if (strchr("$[]!*?", *ptr)) {
299 		    _nc_warning("dubious character `%c' in name or alias field", *ptr);
300 		    break;
301 		}
302 	    }
303 
304 	    ptr = buffer;
305 
306 	    _nc_curr_token.tk_name = buffer;
307 	    type = NAMES;
308 	} else {
309 	    while ((ch = next_char()) != EOF) {
310 		if (!isalnum(ch)) {
311 		    if (_nc_syntax == SYN_TERMINFO) {
312 			if (ch != '_')
313 			    break;
314 		    } else {	/* allow ';' for "k;" */
315 			if (ch != ';')
316 			    break;
317 		    }
318 		}
319 		*(ptr++) = ch;
320 	    }
321 
322 	    *ptr++ = '\0';
323 	    switch (ch) {
324 	    case ',':
325 	    case ':':
326 		if (ch != separator)
327 		    _nc_err_abort("Separator inconsistent with syntax");
328 		_nc_curr_token.tk_name = buffer;
329 		type = BOOLEAN;
330 		break;
331 	    case '@':
332 		if ((ch = next_char()) != separator)
333 		    _nc_warning("Missing separator after `%s', have %s",
334 			buffer, unctrl(ch));
335 		_nc_curr_token.tk_name = buffer;
336 		type = CANCEL;
337 		break;
338 
339 	    case '#':
340 		found = 0;
341 		while (isalnum(ch = next_char())) {
342 		    numbuf[found++] = ch;
343 		    if (found >= sizeof(numbuf) - 1)
344 			break;
345 		}
346 		numbuf[found] = '\0';
347 		number = strtol(numbuf, &numchk, 0);
348 		if (numchk == numbuf)
349 		    _nc_warning("no value given for `%s'", buffer);
350 		if ((*numchk != '\0') || (ch != separator))
351 		    _nc_warning("Missing separator");
352 		_nc_curr_token.tk_name = buffer;
353 		_nc_curr_token.tk_valnumber = number;
354 		type = NUMBER;
355 		break;
356 
357 	    case '=':
358 		ch = _nc_trans_string(ptr, buffer + sizeof(buffer));
359 		if (ch != separator)
360 		    _nc_warning("Missing separator");
361 		_nc_curr_token.tk_name = buffer;
362 		_nc_curr_token.tk_valstring = ptr;
363 		type = STRING;
364 		break;
365 
366 	    case EOF:
367 		type = EOF;
368 		break;
369 	    default:
370 		/* just to get rid of the compiler warning */
371 		type = UNDEF;
372 		_nc_warning("Illegal character - %s", unctrl(ch));
373 	    }
374 	}			/* end else (first_column == FALSE) */
375     }				/* end else (ch != EOF) */
376 
377   end_of_token:
378 
379 #ifdef TRACE
380     if (dot_flag == TRUE)
381 	DEBUG(8, ("Commented out "));
382 
383     if (_nc_tracing >= DEBUG_LEVEL(7)) {
384 	switch (type) {
385 	case BOOLEAN:
386 	    _tracef("Token: Boolean; name='%s'",
387 		_nc_curr_token.tk_name);
388 	    break;
389 
390 	case NUMBER:
391 	    _tracef("Token: Number;  name='%s', value=%d",
392 		_nc_curr_token.tk_name,
393 		_nc_curr_token.tk_valnumber);
394 	    break;
395 
396 	case STRING:
397 	    _tracef("Token: String;  name='%s', value=%s",
398 		_nc_curr_token.tk_name,
399 		_nc_visbuf(_nc_curr_token.tk_valstring));
400 	    break;
401 
402 	case CANCEL:
403 	    _tracef("Token: Cancel; name='%s'",
404 		_nc_curr_token.tk_name);
405 	    break;
406 
407 	case NAMES:
408 
409 	    _tracef("Token: Names; value='%s'",
410 		_nc_curr_token.tk_name);
411 	    break;
412 
413 	case EOF:
414 	    _tracef("Token: End of file");
415 	    break;
416 
417 	default:
418 	    _nc_warning("Bad token type");
419 	}
420     }
421 #endif
422 
423     if (dot_flag == TRUE)	/* if commented out, use the next one */
424 	type = _nc_get_token();
425 
426     DEBUG(3, ("token: `%s', class %d", _nc_curr_token.tk_name, type));
427 
428     return (type);
429 }
430 
431 /*
432  *	char
433  *	trans_string(ptr)
434  *
435  *	Reads characters using next_char() until encountering a separator, nl,
436  *	or end-of-file.  The returned value is the character which caused
437  *	reading to stop.  The following translations are done on the input:
438  *
439  *		^X  goes to  ctrl-X (i.e. X & 037)
440  *		{\E,\n,\r,\b,\t,\f}  go to
441  *			{ESCAPE,newline,carriage-return,backspace,tab,formfeed}
442  *		{\^,\\}  go to  {carat,backslash}
443  *		\ddd (for ddd = up to three octal digits)  goes to the character ddd
444  *
445  *		\e == \E
446  *		\0 == \200
447  *
448  */
449 
450 char
451 _nc_trans_string(char *ptr, char *last)
452 {
453     int count = 0;
454     int number;
455     int i, c;
456     chtype ch, last_ch = '\0';
457     bool ignored = FALSE;
458     bool long_warning = FALSE;
459 
460     while ((ch = c = next_char()) != (chtype) separator && c != EOF) {
461 	if (ptr == (last - 1))
462 	    break;
463 	if ((_nc_syntax == SYN_TERMCAP) && c == '\n')
464 	    break;
465 	if (ch == '^' && last_ch != '%') {
466 	    ch = c = next_char();
467 	    if (c == EOF)
468 		_nc_err_abort("Premature EOF");
469 
470 	    if (!(is7bits(ch) && isprint(ch))) {
471 		_nc_warning("Illegal ^ character - %s", unctrl(ch));
472 	    }
473 	    if (ch == '?') {
474 		*(ptr++) = '\177';
475 	    } else {
476 		if ((ch &= 037) == 0)
477 		    ch = 128;
478 		*(ptr++) = (char) (ch);
479 	    }
480 	} else if (ch == '\\') {
481 	    ch = c = next_char();
482 	    if (c == EOF)
483 		_nc_err_abort("Premature EOF");
484 
485 	    if (ch >= '0' && ch <= '7') {
486 		number = ch - '0';
487 		for (i = 0; i < 2; i++) {
488 		    ch = c = next_char();
489 		    if (c == EOF)
490 			_nc_err_abort("Premature EOF");
491 
492 		    if (c < '0' || c > '7') {
493 			if (isdigit(c)) {
494 			    _nc_warning("Non-octal digit `%c' in \\ sequence", c);
495 			    /* allow the digit; it'll do less harm */
496 			} else {
497 			    push_back((char) c);
498 			    break;
499 			}
500 		    }
501 
502 		    number = number * 8 + c - '0';
503 		}
504 
505 		if (number == 0)
506 		    number = 0200;
507 		*(ptr++) = (char) number;
508 	    } else {
509 		switch (c) {
510 		case 'E':
511 		case 'e':
512 		    *(ptr++) = '\033';
513 		    break;
514 
515 		case 'a':
516 		    *(ptr++) = '\007';
517 		    break;
518 
519 		case 'l':
520 		case 'n':
521 		    *(ptr++) = '\n';
522 		    break;
523 
524 		case 'r':
525 		    *(ptr++) = '\r';
526 		    break;
527 
528 		case 'b':
529 		    *(ptr++) = '\010';
530 		    break;
531 
532 		case 's':
533 		    *(ptr++) = ' ';
534 		    break;
535 
536 		case 'f':
537 		    *(ptr++) = '\014';
538 		    break;
539 
540 		case 't':
541 		    *(ptr++) = '\t';
542 		    break;
543 
544 		case '\\':
545 		    *(ptr++) = '\\';
546 		    break;
547 
548 		case '^':
549 		    *(ptr++) = '^';
550 		    break;
551 
552 		case ',':
553 		    *(ptr++) = ',';
554 		    break;
555 
556 		case ':':
557 		    *(ptr++) = ':';
558 		    break;
559 
560 		case '\n':
561 		    continue;
562 
563 		default:
564 		    _nc_warning("Illegal character %s in \\ sequence",
565 			unctrl(ch));
566 		    *(ptr++) = (char) ch;
567 		}		/* endswitch (ch) */
568 	    }			/* endelse (ch < '0' ||  ch > '7') */
569 	}
570 	/* end else if (ch == '\\') */
571 	else if (ch == '\n' && (_nc_syntax == SYN_TERMINFO)) {
572 	    /* newlines embedded in a terminfo string are ignored */
573 	    ignored = TRUE;
574 	} else {
575 	    *(ptr++) = (char) ch;
576 	}
577 
578 	if (!ignored) {
579 	    last_ch = ch;
580 	    count++;
581 	}
582 	ignored = FALSE;
583 
584 	if (count > MAXCAPLEN && !long_warning) {
585 	    _nc_warning("Very long string found.  Missing separator?");
586 	    long_warning = TRUE;
587 	}
588     }				/* end while */
589 
590     *ptr = '\0';
591 
592     return (ch);
593 }
594 
595 /*
596  *	_nc_push_token()
597  *
598  *	Push a token of given type so that it will be reread by the next
599  *	get_token() call.
600  */
601 
602 void
603 _nc_push_token(int tokclass)
604 {
605     /*
606      * This implementation is kind of bogus, it will fail if we ever do
607      * more than one pushback at a time between get_token() calls.  It
608      * relies on the fact that curr_tok is static storage that nothing
609      * but get_token() touches.
610      */
611     pushtype = tokclass;
612     _nc_get_type(pushname);
613 
614     DEBUG(3, ("pushing token: `%s', class %d",
615 	    _nc_curr_token.tk_name, pushtype));
616 }
617 
618 /*
619  * Panic mode error recovery - skip everything until a "ch" is found.
620  */
621 void
622 _nc_panic_mode(char ch)
623 {
624     int c;
625 
626     for (;;) {
627 	c = next_char();
628 	if (c == ch)
629 	    return;
630 	if (c == EOF)
631 	    return;
632     }
633 }
634 
635 /*****************************************************************************
636  *
637  * Character-stream handling
638  *
639  *****************************************************************************/
640 
641 #define LEXBUFSIZ	1024
642 
643 static char *bufptr;		/* otherwise, the input buffer pointer */
644 static char *bufstart;		/* start of buffer so we can compute offsets */
645 static FILE *yyin;		/* scanner's input file descriptor */
646 
647 /*
648  *	_nc_reset_input()
649  *
650  *	Resets the input-reading routines.  Used on initialization,
651  *	or after a seek has been done.  Exactly one argument must be
652  *	non-null.
653  */
654 
655 void
656 _nc_reset_input(FILE * fp, char *buf)
657 {
658     pushtype = NO_PUSHBACK;
659     pushname[0] = '\0';
660     yyin = fp;
661     bufstart = bufptr = buf;
662     _nc_curr_file_pos = 0L;
663     if (fp != 0)
664 	_nc_curr_line = 0;
665     _nc_curr_col = 0;
666 }
667 
668 /*
669  *	int last_char()
670  *
671  *	Returns the final nonblank character on the current input buffer
672  */
673 static int
674 last_char(void)
675 {
676     size_t len = strlen(bufptr);
677     while (len--) {
678 	if (!isspace(bufptr[len]))
679 	    return bufptr[len];
680     }
681     return 0;
682 }
683 
684 /*
685  *	int next_char()
686  *
687  *	Returns the next character in the input stream.  Comments and leading
688  *	white space are stripped.
689  *
690  *	The global state variable 'firstcolumn' is set TRUE if the character
691  *	returned is from the first column of the input line.
692  *
693  *	The global variable _nc_curr_line is incremented for each new line.
694  *	The global variable _nc_curr_file_pos is set to the file offset of the
695  *	beginning of each line.
696  */
697 
698 static int
699 next_char(void)
700 {
701     if (!yyin) {
702 	if (*bufptr == '\0')
703 	    return (EOF);
704 	if (*bufptr == '\n') {
705 	    _nc_curr_line++;
706 	    _nc_curr_col = 0;
707 	}
708     } else if (!bufptr || !*bufptr) {
709 	/*
710 	 * In theory this could be recoded to do its I/O one
711 	 * character at a time, saving the buffer space.  In
712 	 * practice, this turns out to be quite hard to get
713 	 * completely right.  Try it and see.  If you succeed,
714 	 * don't forget to hack push_back() correspondingly.
715 	 */
716 	static char line[LEXBUFSIZ];
717 	size_t len;
718 
719 	do {
720 	    _nc_curr_file_pos = ftell(yyin);
721 
722 	    if ((bufstart = fgets(line, LEXBUFSIZ, yyin)) != NULL) {
723 		_nc_curr_line++;
724 		_nc_curr_col = 0;
725 	    }
726 	    bufptr = bufstart;
727 	} while
728 	    (bufstart != NULL && line[0] == '#');
729 
730 	if (bufstart == NULL)
731 	    return (EOF);
732 
733 	while (iswhite(*bufptr))
734 	    bufptr++;
735 
736 	/*
737 	 * Treat a trailing <cr><lf> the same as a <newline> so we can read
738 	 * files on OS/2, etc.
739 	 */
740 	if ((len = strlen(bufptr)) > 1) {
741 	    if (bufptr[len - 1] == '\n'
742 		&& bufptr[len - 2] == '\r') {
743 		bufptr[len - 2] = '\n';
744 		bufptr[len - 1] = '\0';
745 	    }
746 	}
747     }
748 
749     first_column = (bufptr == bufstart);
750 
751     _nc_curr_col++;
752     return (*bufptr++);
753 }
754 
755 static void
756 push_back(char c)
757 /* push a character back onto the input stream */
758 {
759     if (bufptr == bufstart)
760 	_nc_syserr_abort("Can't backspace off beginning of line");
761     *--bufptr = c;
762 }
763 
764 static long
765 stream_pos(void)
766 /* return our current character position in the input stream */
767 {
768     return (yyin ? ftell(yyin) : (bufptr ? bufptr - bufstart : 0));
769 }
770 
771 static bool
772 end_of_stream(void)
773 /* are we at end of input? */
774 {
775     return ((yyin ? feof(yyin) : (bufptr && *bufptr == '\0'))
776 	? TRUE : FALSE);
777 }
778 
779 /* comp_scan.c ends here */
780