1 /****************************************************************************
2  * Copyright 2020 Thomas E. Dickey                                          *
3  * Copyright 1998-2016,2017 Free Software Foundation, Inc.                  *
4  *                                                                          *
5  * Permission is hereby granted, free of charge, to any person obtaining a  *
6  * copy of this software and associated documentation files (the            *
7  * "Software"), to deal in the Software without restriction, including      *
8  * without limitation the rights to use, copy, modify, merge, publish,      *
9  * distribute, distribute with modifications, sublicense, and/or sell       *
10  * copies of the Software, and to permit persons to whom the Software is    *
11  * furnished to do so, subject to the following conditions:                 *
12  *                                                                          *
13  * The above copyright notice and this permission notice shall be included  *
14  * in all copies or substantial portions of the Software.                   *
15  *                                                                          *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
19  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
20  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
21  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
22  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
23  *                                                                          *
24  * Except as contained in this notice, the name(s) of the above copyright   *
25  * holders shall not be used in advertising or otherwise to promote the     *
26  * sale, use or other dealings in this Software without prior written       *
27  * authorization.                                                           *
28  ****************************************************************************/
29 
30 /****************************************************************************
31  *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
32  *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
33  *     and: Thomas E. Dickey                        1996 on                 *
34  ****************************************************************************/
35 
36 /*
37  *	comp_scan.c --- Lexical scanner for terminfo compiler.
38  *
39  *	_nc_reset_input()
40  *	_nc_get_token()
41  *	_nc_panic_mode()
42  *	int _nc_syntax;
43  *	int _nc_curr_line;
44  *	long _nc_curr_file_pos;
45  *	long _nc_comment_start;
46  *	long _nc_comment_end;
47  */
48 
49 #include <curses.priv.h>
50 
51 #include <ctype.h>
52 #include <tic.h>
53 
54 MODULE_ID("$Id: comp_scan.c,v 1.109 2020/02/02 23:34:34 tom Exp $")
55 
56 /*
57  * Maximum length of string capability we'll accept before raising an error.
58  * Yes, there is a real capability in /etc/termcap this long, an "is".
59  */
60 #define MAXCAPLEN	600
61 
62 #define iswhite(ch)	(ch == ' '  ||  ch == '\t')
63 
64 NCURSES_EXPORT_VAR (int) _nc_syntax = 0;         /* termcap or terminfo? */
65 NCURSES_EXPORT_VAR (int) _nc_strict_bsd = 1;  /* ncurses extended termcap? */
66 NCURSES_EXPORT_VAR (long) _nc_curr_file_pos = 0; /* file offset of current line */
67 NCURSES_EXPORT_VAR (long) _nc_comment_start = 0; /* start of comment range before name */
68 NCURSES_EXPORT_VAR (long) _nc_comment_end = 0;   /* end of comment range before name */
69 NCURSES_EXPORT_VAR (long) _nc_start_line = 0;    /* start line of current entry */
70 
71 NCURSES_EXPORT_VAR (struct token) _nc_curr_token =
72 {
73     0, 0, 0
74 };
75 
76 /*****************************************************************************
77  *
78  * Token-grabbing machinery
79  *
80  *****************************************************************************/
81 
82 static bool first_column;	/* See 'next_char()' below */
83 static bool had_newline;
84 static char separator;		/* capability separator */
85 static int pushtype;		/* type of pushback token */
86 static char *pushname;
87 
88 #if NCURSES_EXT_FUNCS
89 NCURSES_EXPORT_VAR (bool) _nc_disable_period = FALSE; /* used by tic -a option */
90 #endif
91 
92 /*****************************************************************************
93  *
94  * Character-stream handling
95  *
96  *****************************************************************************/
97 
98 #define LEXBUFSIZ	1024
99 
100 static char *bufptr;		/* otherwise, the input buffer pointer */
101 static char *bufstart;		/* start of buffer so we can compute offsets */
102 static FILE *yyin;		/* scanner's input file descriptor */
103 
104 /*
105  *	_nc_reset_input()
106  *
107  *	Resets the input-reading routines.  Used on initialization,
108  *	or after a seek has been done.  Exactly one argument must be
109  *	non-null.
110  */
111 
112 NCURSES_EXPORT(void)
113 _nc_reset_input(FILE *fp, char *buf)
114 {
115     pushtype = NO_PUSHBACK;
116     if (pushname != 0)
117 	pushname[0] = '\0';
118     yyin = fp;
119     bufstart = bufptr = buf;
120     _nc_curr_file_pos = 0L;
121     if (fp != 0)
122 	_nc_curr_line = 0;
123     _nc_curr_col = 0;
124 }
125 
126 /*
127  *	int last_char()
128  *
129  *	Returns the final nonblank character on the current input buffer
130  */
131 static int
132 last_char(int from_end)
133 {
134     size_t len = strlen(bufptr);
135     int result = 0;
136 
137     while (len--) {
138 	if (!isspace(UChar(bufptr[len]))) {
139 	    if (from_end < (int) len)
140 		result = bufptr[(int) len - from_end];
141 	    break;
142 	}
143     }
144     return result;
145 }
146 
147 /*
148  *	int next_char()
149  *
150  *	Returns the next character in the input stream.  Comments and leading
151  *	white space are stripped.
152  *
153  *	The global state variable 'firstcolumn' is set TRUE if the character
154  *	returned is from the first column of the input line.
155  *
156  *	The global variable _nc_curr_line is incremented for each new line.
157  *	The global variable _nc_curr_file_pos is set to the file offset of the
158  *	beginning of each line.
159  */
160 
161 static int
162 next_char(void)
163 {
164     static char *result;
165     static size_t allocated;
166     int the_char;
167 
168     if (!yyin) {
169 	if (result != 0) {
170 	    FreeAndNull(result);
171 	    FreeAndNull(pushname);
172 	    bufptr = 0;
173 	    bufstart = 0;
174 	    allocated = 0;
175 	}
176 	/*
177 	 * An string with an embedded null will truncate the input.  This is
178 	 * intentional (we don't read binary files here).
179 	 */
180 	if (bufptr == 0 || *bufptr == '\0')
181 	    return (EOF);
182 	if (*bufptr == '\n') {
183 	    _nc_curr_line++;
184 	    _nc_curr_col = 0;
185 	} else if (*bufptr == '\t') {
186 	    _nc_curr_col = (_nc_curr_col | 7);
187 	}
188     } else if (!bufptr || !*bufptr) {
189 	/*
190 	 * In theory this could be recoded to do its I/O one character at a
191 	 * time, saving the buffer space.  In practice, this turns out to be
192 	 * quite hard to get completely right.  Try it and see.  If you
193 	 * succeed, don't forget to hack push_back() correspondingly.
194 	 */
195 	size_t len;
196 
197 	do {
198 	    size_t used = 0;
199 	    bufstart = 0;
200 	    do {
201 		if (used + (LEXBUFSIZ / 4) >= allocated) {
202 		    allocated += (allocated + LEXBUFSIZ);
203 		    result = typeRealloc(char, allocated, result);
204 		    if (result == 0)
205 			return (EOF);
206 		    if (bufstart)
207 			bufstart = result;
208 		}
209 		if (used == 0)
210 		    _nc_curr_file_pos = ftell(yyin);
211 
212 		if (fgets(result + used, (int) (allocated - used), yyin) != 0) {
213 		    bufstart = result;
214 		    if (used == 0) {
215 			if (_nc_curr_line == 0
216 			    && IS_TIC_MAGIC(result)) {
217 			    _nc_err_abort("This is a compiled terminal description, not a source");
218 			}
219 			_nc_curr_line++;
220 			_nc_curr_col = 0;
221 		    }
222 		} else {
223 		    if (used != 0)
224 			_nc_STRCAT(result, "\n", allocated);
225 		}
226 		if ((bufptr = bufstart) != 0) {
227 		    used = strlen(bufptr);
228 		    if (used == 0)
229 			return (EOF);
230 		    while (iswhite(*bufptr)) {
231 			if (*bufptr == '\t') {
232 			    _nc_curr_col = (_nc_curr_col | 7) + 1;
233 			} else {
234 			    _nc_curr_col++;
235 			}
236 			bufptr++;
237 		    }
238 
239 		    /*
240 		     * Treat a trailing <cr><lf> the same as a <newline> so we
241 		     * can read files on OS/2, etc.
242 		     */
243 		    if ((len = strlen(bufptr)) > 1) {
244 			if (bufptr[len - 1] == '\n'
245 			    && bufptr[len - 2] == '\r') {
246 			    len--;
247 			    bufptr[len - 1] = '\n';
248 			    bufptr[len] = '\0';
249 			}
250 		    }
251 		} else {
252 		    return (EOF);
253 		}
254 	    } while (bufptr[len - 1] != '\n');	/* complete a line */
255 	} while (result[0] == '#');	/* ignore comments */
256     } else if (*bufptr == '\t') {
257 	_nc_curr_col = (_nc_curr_col | 7);
258     }
259 
260     first_column = (bufptr == bufstart);
261     if (first_column)
262 	had_newline = FALSE;
263 
264     _nc_curr_col++;
265     the_char = *bufptr++;
266     return UChar(the_char);
267 }
268 
269 static void
270 push_back(int c)
271 /* push a character back onto the input stream */
272 {
273     if (bufptr == bufstart)
274 	_nc_syserr_abort("Can't backspace off beginning of line");
275     *--bufptr = (char) c;
276     _nc_curr_col--;
277 }
278 
279 static long
280 stream_pos(void)
281 /* return our current character position in the input stream */
282 {
283     return (yyin ? ftell(yyin) : (bufptr ? bufptr - bufstart : 0));
284 }
285 
286 static bool
287 end_of_stream(void)
288 /* are we at end of input? */
289 {
290     return ((yyin ? feof(yyin) : (bufptr && *bufptr == '\0'))
291 	    ? TRUE : FALSE);
292 }
293 
294 /* Assume we may be looking at a termcap-style continuation */
295 static NCURSES_INLINE int
296 eat_escaped_newline(int ch)
297 {
298     if (ch == '\\')
299 	while ((ch = next_char()) == '\n' || iswhite(ch))
300 	    continue;
301     return ch;
302 }
303 
304 #define TOK_BUF_SIZE MAX_ENTRY_SIZE
305 
306 #define OkToAdd() \
307 	((tok_ptr - tok_buf) < (TOK_BUF_SIZE - 2))
308 
309 #define AddCh(ch) \
310 	*tok_ptr++ = (char) ch; \
311 	*tok_ptr = '\0'
312 
313 static char *tok_buf;
314 
315 /*
316  *	int
317  *	get_token()
318  *
319  *	Scans the input for the next token, storing the specifics in the
320  *	global structure 'curr_token' and returning one of the following:
321  *
322  *		NAMES		A line beginning in column 1.  'name'
323  *				will be set to point to everything up to but
324  *				not including the first separator on the line.
325  *		BOOLEAN		An entry consisting of a name followed by
326  *				a separator.  'name' will be set to point to
327  *				the name of the capability.
328  *		NUMBER		An entry of the form
329  *					name#digits,
330  *				'name' will be set to point to the capability
331  *				name and 'valnumber' to the number given.
332  *		STRING		An entry of the form
333  *					name=characters,
334  *				'name' is set to the capability name and
335  *				'valstring' to the string of characters, with
336  *				input translations done.
337  *		CANCEL		An entry of the form
338  *					name@,
339  *				'name' is set to the capability name and
340  *				'valnumber' to -1.
341  *		EOF		The end of the file has been reached.
342  *
343  *	A `separator' is either a comma or a semicolon, depending on whether
344  *	we are in termcap or terminfo mode.
345  *
346  */
347 
348 NCURSES_EXPORT(int)
349 _nc_get_token(bool silent)
350 {
351     static const char terminfo_punct[] = "@%&*!#";
352 
353     char *after_name;		/* after primary name */
354     char *after_list;		/* after primary and alias list */
355     char *numchk;
356     char *tok_ptr;
357     char *s;
358     char numbuf[80];
359     int ch, c0, c1;
360     int dot_flag = FALSE;
361     int type;
362     long number;
363     long token_start;
364     unsigned found;
365 #ifdef TRACE
366     int old_line;
367     int old_col;
368 #endif
369 
370     if (pushtype != NO_PUSHBACK) {
371 	int retval = pushtype;
372 
373 	_nc_set_type(pushname != 0 ? pushname : "");
374 	DEBUG(3, ("pushed-back token: `%s', class %d",
375 		  _nc_curr_token.tk_name, pushtype));
376 
377 	pushtype = NO_PUSHBACK;
378 	if (pushname != 0)
379 	    pushname[0] = '\0';
380 
381 	/* currtok wasn't altered by _nc_push_token() */
382 	return (retval);
383     }
384 
385     if (end_of_stream()) {
386 	yyin = 0;
387 	(void) next_char();	/* frees its allocated memory */
388 	if (tok_buf != 0) {
389 	    if (_nc_curr_token.tk_name == tok_buf)
390 		_nc_curr_token.tk_name = 0;
391 	}
392 	return (EOF);
393     }
394 
395   start_token:
396     token_start = stream_pos();
397     while ((ch = next_char()) == '\n' || iswhite(ch)) {
398 	if (ch == '\n')
399 	    had_newline = TRUE;
400 	continue;
401     }
402 
403     ch = eat_escaped_newline(ch);
404     _nc_curr_token.tk_valstring = 0;
405 
406 #ifdef TRACE
407     old_line = _nc_curr_line;
408     old_col = _nc_curr_col;
409 #endif
410     if (ch == EOF)
411 	type = EOF;
412     else {
413 	/* if this is a termcap entry, skip a leading separator */
414 	if (separator == ':' && ch == ':')
415 	    ch = next_char();
416 
417 	if (ch == '.'
418 #if NCURSES_EXT_FUNCS
419 	    && !_nc_disable_period
420 #endif
421 	    ) {
422 	    dot_flag = TRUE;
423 	    DEBUG(8, ("dot-flag set"));
424 
425 	    while ((ch = next_char()) == '.' || iswhite(ch))
426 		continue;
427 	}
428 
429 	if (ch == EOF) {
430 	    type = EOF;
431 	    goto end_of_token;
432 	}
433 
434 	/* have to make some punctuation chars legal for terminfo */
435 	if (!isalnum(UChar(ch))
436 #if NCURSES_EXT_FUNCS
437 	    && !(ch == '.' && _nc_disable_period)
438 #endif
439 	    && ((strchr) (terminfo_punct, (char) ch) == 0)) {
440 	    if (!silent)
441 		_nc_warning("Illegal character (expected alphanumeric or %s) - '%s'",
442 			    terminfo_punct, unctrl(UChar(ch)));
443 	    _nc_panic_mode(separator);
444 	    goto start_token;
445 	}
446 
447 	if (tok_buf == 0)
448 	    tok_buf = typeMalloc(char, TOK_BUF_SIZE);
449 
450 #ifdef TRACE
451 	old_line = _nc_curr_line;
452 	old_col = _nc_curr_col;
453 #endif
454 	tok_ptr = tok_buf;
455 	AddCh(ch);
456 
457 	if (first_column) {
458 	    _nc_comment_start = token_start;
459 	    _nc_comment_end = _nc_curr_file_pos;
460 	    _nc_start_line = _nc_curr_line;
461 
462 	    _nc_syntax = ERR;
463 	    after_name = 0;
464 	    after_list = 0;
465 	    while ((ch = next_char()) != '\n') {
466 		if (ch == EOF) {
467 		    _nc_err_abort(MSG_NO_INPUTS);
468 		} else if (ch == '|') {
469 		    after_list = tok_ptr;
470 		    if (after_name == 0)
471 			after_name = tok_ptr;
472 		} else if (ch == ':' && last_char(0) != ',') {
473 		    _nc_syntax = SYN_TERMCAP;
474 		    separator = ':';
475 		    break;
476 		} else if (ch == ',') {
477 		    _nc_syntax = SYN_TERMINFO;
478 		    separator = ',';
479 		    /*
480 		     * If we did not see a '|', then we found a name with no
481 		     * aliases or description.
482 		     */
483 		    if (after_name == 0)
484 			break;
485 		    /*
486 		     * We saw a comma, but are not entirely sure this is
487 		     * terminfo format, since we can still be parsing the
488 		     * description field (for either syntax).
489 		     *
490 		     * A properly formatted termcap line ends with either a
491 		     * colon, or a backslash after a colon.  It is possible
492 		     * to have a backslash in the middle of a capability, but
493 		     * then there would be no leading whitespace on the next
494 		     * line - something we want to discourage.
495 		     */
496 		    c0 = last_char(0);
497 		    c1 = last_char(1);
498 		    if (c1 != ':' && c0 != '\\' && c0 != ':') {
499 			bool capability = FALSE;
500 
501 			/*
502 			 * Since it is not termcap, assume the line is terminfo
503 			 * format.  However, the comma can be embedded in a
504 			 * description field.  It also can be a separator
505 			 * between a description field and a capability.
506 			 *
507 			 * Improve the guess by checking if the next word after
508 			 * the comma does not look like a capability.  In that
509 			 * case, extend the description past the comma.
510 			 */
511 			for (s = bufptr; isspace(UChar(*s)); ++s) {
512 			    ;
513 			}
514 			if (islower(UChar(*s))) {
515 			    char *name = s;
516 			    while (isalnum(UChar(*s))) {
517 				++s;
518 			    }
519 			    if (*s == '#' || *s == '=' || *s == '@') {
520 				/*
521 				 * Checking solely with syntax allows us to
522 				 * support extended capabilities with string
523 				 * values.
524 				 */
525 				capability = TRUE;
526 			    } else if (*s == ',') {
527 				c0 = *s;
528 				*s = '\0';
529 				/*
530 				 * Otherwise, we can handle predefined boolean
531 				 * capabilities, still aided by syntax.
532 				 */
533 				if (_nc_find_entry(name,
534 						   _nc_get_hash_table(FALSE))) {
535 				    capability = TRUE;
536 				}
537 				*s = (char) c0;
538 			    }
539 			}
540 			if (capability) {
541 			    break;
542 			}
543 		    }
544 		} else
545 		    ch = eat_escaped_newline(ch);
546 
547 		if (OkToAdd()) {
548 		    AddCh(ch);
549 		} else {
550 		    break;
551 		}
552 	    }
553 	    *tok_ptr = '\0';
554 	    if (_nc_syntax == ERR) {
555 		/*
556 		 * Grrr...what we ought to do here is barf, complaining that
557 		 * the entry is malformed.  But because a couple of name fields
558 		 * in the 8.2 termcap file end with |\, we just have to assume
559 		 * it's termcap syntax.
560 		 */
561 		_nc_syntax = SYN_TERMCAP;
562 		separator = ':';
563 	    } else if (_nc_syntax == SYN_TERMINFO) {
564 		/* throw away trailing /, *$/ */
565 		for (--tok_ptr;
566 		     iswhite(*tok_ptr) || *tok_ptr == ',';
567 		     tok_ptr--)
568 		    continue;
569 		tok_ptr[1] = '\0';
570 	    }
571 
572 	    /*
573 	     * This is the soonest we have the terminal name fetched.  Set up
574 	     * for following warning messages.  If there's no '|', then there
575 	     * is no description.
576 	     */
577 	    if (after_name != 0) {
578 		ch = *after_name;
579 		*after_name = '\0';
580 		_nc_set_type(tok_buf);
581 		*after_name = (char) ch;
582 	    }
583 
584 	    /*
585 	     * Compute the boundary between the aliases and the description
586 	     * field for syntax-checking purposes.
587 	     */
588 	    if (after_list != 0) {
589 		if (!silent) {
590 		    if (*after_list == '\0')
591 			_nc_warning("empty longname field");
592 #ifndef DRAGONFLY_NATIVE
593 		    else if (strchr(after_list, ' ') == 0)
594 			_nc_warning("older tic versions may treat the description field as an alias");
595 #endif
596 		}
597 	    } else {
598 		after_list = tok_buf + strlen(tok_buf);
599 		DEBUG(1, ("missing description"));
600 	    }
601 
602 	    /*
603 	     * Whitespace in a name field other than the long name can confuse
604 	     * rdist and some termcap tools.  Slashes are a no-no.  Other
605 	     * special characters can be dangerous due to shell expansion.
606 	     */
607 	    for (s = tok_buf; s < after_list; ++s) {
608 		if (isspace(UChar(*s))) {
609 		    if (!silent)
610 			_nc_warning("whitespace in name or alias field");
611 		    break;
612 		} else if (*s == '/') {
613 		    if (!silent)
614 			_nc_warning("slashes aren't allowed in names or aliases");
615 		    break;
616 		} else if (strchr("$[]!*?", *s)) {
617 		    if (!silent)
618 			_nc_warning("dubious character `%c' in name or alias field", *s);
619 		    break;
620 		}
621 	    }
622 
623 	    _nc_curr_token.tk_name = tok_buf;
624 	    type = NAMES;
625 	} else {
626 	    if (had_newline && _nc_syntax == SYN_TERMCAP) {
627 		_nc_warning("Missing backslash before newline");
628 		had_newline = FALSE;
629 	    }
630 	    while ((ch = next_char()) != EOF) {
631 		if (!isalnum(UChar(ch))) {
632 		    if (_nc_syntax == SYN_TERMINFO) {
633 			if (ch != '_')
634 			    break;
635 		    } else {	/* allow ';' for "k;" */
636 			if (ch != ';')
637 			    break;
638 		    }
639 		}
640 		if (OkToAdd()) {
641 		    AddCh(ch);
642 		} else {
643 		    ch = EOF;
644 		    break;
645 		}
646 	    }
647 
648 	    *tok_ptr++ = '\0';	/* separate name/value in buffer */
649 	    switch (ch) {
650 	    case ',':
651 	    case ':':
652 		if (ch != separator)
653 		    _nc_err_abort("Separator inconsistent with syntax");
654 		_nc_curr_token.tk_name = tok_buf;
655 		type = BOOLEAN;
656 		break;
657 	    case '@':
658 		if ((ch = next_char()) != separator && !silent)
659 		    _nc_warning("Missing separator after `%s', have %s",
660 				tok_buf, unctrl(UChar(ch)));
661 		_nc_curr_token.tk_name = tok_buf;
662 		type = CANCEL;
663 		break;
664 
665 	    case '#':
666 		found = 0;
667 		while (isalnum(ch = next_char())) {
668 		    numbuf[found++] = (char) ch;
669 		    if (found >= sizeof(numbuf) - 1)
670 			break;
671 		}
672 		numbuf[found] = '\0';
673 		number = strtol(numbuf, &numchk, 0);
674 		if (!silent) {
675 		    if (numchk == numbuf)
676 			_nc_warning("no value given for `%s'", tok_buf);
677 		    if ((*numchk != '\0') || (ch != separator))
678 			_nc_warning("Missing separator for `%s'", tok_buf);
679 		    if (number < 0)
680 			_nc_warning("value of `%s' cannot be negative", tok_buf);
681 		    if (number > MAX_OF_TYPE(NCURSES_INT2)) {
682 			_nc_warning("limiting value of `%s' from %#lx to %#x",
683 				    tok_buf,
684 				    number, MAX_OF_TYPE(NCURSES_INT2));
685 			number = MAX_OF_TYPE(NCURSES_INT2);
686 		    }
687 		}
688 		_nc_curr_token.tk_name = tok_buf;
689 		_nc_curr_token.tk_valnumber = (int) number;
690 		type = NUMBER;
691 		break;
692 
693 	    case '=':
694 		ch = _nc_trans_string(tok_ptr, tok_buf + TOK_BUF_SIZE);
695 		if (!silent && ch != separator)
696 		    _nc_warning("Missing separator");
697 		_nc_curr_token.tk_name = tok_buf;
698 		_nc_curr_token.tk_valstring = tok_ptr;
699 		type = STRING;
700 		break;
701 
702 	    case EOF:
703 		type = EOF;
704 		break;
705 	    default:
706 		/* just to get rid of the compiler warning */
707 		type = UNDEF;
708 		if (!silent)
709 		    _nc_warning("Illegal character - '%s'", unctrl(UChar(ch)));
710 	    }
711 	}			/* end else (first_column == FALSE) */
712     }				/* end else (ch != EOF) */
713 
714   end_of_token:
715 
716 #ifdef TRACE
717     if (dot_flag == TRUE)
718 	DEBUG(8, ("Commented out "));
719 
720     if (_nc_tracing >= DEBUG_LEVEL(8)) {
721 	_tracef("parsed %d.%d to %d.%d",
722 		old_line, old_col,
723 		_nc_curr_line, _nc_curr_col);
724     }
725     if (_nc_tracing >= DEBUG_LEVEL(7)) {
726 	switch (type) {
727 	case BOOLEAN:
728 	    _tracef("Token: Boolean; name='%s'",
729 		    _nc_curr_token.tk_name);
730 	    break;
731 
732 	case NUMBER:
733 	    _tracef("Token: Number;  name='%s', value=%d",
734 		    _nc_curr_token.tk_name,
735 		    _nc_curr_token.tk_valnumber);
736 	    break;
737 
738 	case STRING:
739 	    _tracef("Token: String;  name='%s', value=%s",
740 		    _nc_curr_token.tk_name,
741 		    _nc_visbuf(_nc_curr_token.tk_valstring));
742 	    break;
743 
744 	case CANCEL:
745 	    _tracef("Token: Cancel; name='%s'",
746 		    _nc_curr_token.tk_name);
747 	    break;
748 
749 	case NAMES:
750 
751 	    _tracef("Token: Names; value='%s'",
752 		    _nc_curr_token.tk_name);
753 	    break;
754 
755 	case EOF:
756 	    _tracef("Token: End of file");
757 	    break;
758 
759 	default:
760 	    _nc_warning("Bad token type");
761 	}
762     }
763 #endif
764 
765     if (dot_flag == TRUE)	/* if commented out, use the next one */
766 	type = _nc_get_token(silent);
767 
768     DEBUG(3, ("token: `%s', class %d",
769 	      ((_nc_curr_token.tk_name != 0)
770 	       ? _nc_curr_token.tk_name
771 	       : "<null>"),
772 	      type));
773 
774     return (type);
775 }
776 
777 /*
778  *	char
779  *	trans_string(ptr)
780  *
781  *	Reads characters using next_char() until encountering a separator, nl,
782  *	or end-of-file.  The returned value is the character which caused
783  *	reading to stop.  The following translations are done on the input:
784  *
785  *		^X  goes to  ctrl-X (i.e. X & 037)
786  *		{\E,\n,\r,\b,\t,\f}  go to
787  *			{ESCAPE,newline,carriage-return,backspace,tab,formfeed}
788  *		{\^,\\}  go to  {carat,backslash}
789  *		\ddd (for ddd = up to three octal digits)  goes to the character ddd
790  *
791  *		\e == \E
792  *		\0 == \200
793  *
794  */
795 
796 NCURSES_EXPORT(int)
797 _nc_trans_string(char *ptr, char *last)
798 {
799     int count = 0;
800     int number = 0;
801     int i, c;
802     int last_ch = '\0';
803     bool ignored = FALSE;
804     bool long_warning = FALSE;
805 
806     while ((c = next_char()) != separator && c != EOF) {
807 	if (ptr >= (last - 1)) {
808 	    if (c != EOF) {
809 		while ((c = next_char()) != separator && c != EOF) {
810 		    ;
811 		}
812 	    }
813 	    break;
814 	}
815 	if ((_nc_syntax == SYN_TERMCAP) && c == '\n')
816 	    break;
817 	if (c == '^' && last_ch != '%') {
818 	    c = next_char();
819 	    if (c == EOF)
820 		_nc_err_abort(MSG_NO_INPUTS);
821 
822 	    if (!(is7bits(c) && isprint(c))) {
823 		_nc_warning("Illegal ^ character - '%s'", unctrl(UChar(c)));
824 	    }
825 	    if (c == '?' && (_nc_syntax != SYN_TERMCAP)) {
826 		*(ptr++) = '\177';
827 	    } else {
828 		if ((c &= 037) == 0)
829 		    c = 128;
830 		*(ptr++) = (char) (c);
831 	    }
832 	} else if (c == '\\') {
833 	    bool strict_bsd = ((_nc_syntax == SYN_TERMCAP) && _nc_strict_bsd);
834 
835 	    c = next_char();
836 	    if (c == EOF)
837 		_nc_err_abort(MSG_NO_INPUTS);
838 
839 	    if (isoctal(c) || (strict_bsd && isdigit(c))) {
840 		number = c - '0';
841 		for (i = 0; i < 2; i++) {
842 		    c = next_char();
843 		    if (c == EOF)
844 			_nc_err_abort(MSG_NO_INPUTS);
845 
846 		    if (!isoctal(c)) {
847 			if (isdigit(c)) {
848 			    if (!strict_bsd) {
849 				_nc_warning("Non-octal digit `%c' in \\ sequence", c);
850 				/* allow the digit; it'll do less harm */
851 			    }
852 			} else {
853 			    push_back(c);
854 			    break;
855 			}
856 		    }
857 
858 		    number = number * 8 + c - '0';
859 		}
860 
861 		number = UChar(number);
862 		if (number == 0 && !strict_bsd)
863 		    number = 0200;
864 		*(ptr++) = (char) number;
865 	    } else {
866 		switch (c) {
867 		case 'E':
868 		    *(ptr++) = '\033';
869 		    break;
870 
871 		case 'n':
872 		    *(ptr++) = '\n';
873 		    break;
874 
875 		case 'r':
876 		    *(ptr++) = '\r';
877 		    break;
878 
879 		case 'b':
880 		    *(ptr++) = '\010';
881 		    break;
882 
883 		case 'f':
884 		    *(ptr++) = '\014';
885 		    break;
886 
887 		case 't':
888 		    *(ptr++) = '\t';
889 		    break;
890 
891 		case '\\':
892 		    *(ptr++) = '\\';
893 		    break;
894 
895 		case '^':
896 		    *(ptr++) = '^';
897 		    break;
898 
899 		case ',':
900 		    *(ptr++) = ',';
901 		    break;
902 
903 		case '\n':
904 		    continue;
905 
906 		default:
907 		    if ((_nc_syntax == SYN_TERMINFO) || !_nc_strict_bsd) {
908 			switch (c) {
909 			case 'a':
910 			    c = '\007';
911 			    break;
912 			case 'e':
913 			    c = '\033';
914 			    break;
915 			case 'l':
916 			    c = '\n';
917 			    break;
918 			case 's':
919 			    c = ' ';
920 			    break;
921 			case ':':
922 			    c = ':';
923 			    break;
924 			default:
925 			    _nc_warning("Illegal character '%s' in \\ sequence",
926 					unctrl(UChar(c)));
927 			    break;
928 			}
929 		    }
930 		    /* FALLTHRU */
931 		case '|':
932 		    *(ptr++) = (char) c;
933 		}		/* endswitch (c) */
934 	    }			/* endelse (c < '0' ||  c > '7') */
935 	}
936 	/* end else if (c == '\\') */
937 	else if (c == '\n' && (_nc_syntax == SYN_TERMINFO)) {
938 	    /*
939 	     * Newlines embedded in a terminfo string are ignored, provided
940 	     * that the next line begins with whitespace.
941 	     */
942 	    ignored = TRUE;
943 	} else {
944 	    *(ptr++) = (char) c;
945 	}
946 
947 	if (!ignored) {
948 	    if (_nc_curr_col <= 1) {
949 		push_back(c);
950 		c = '\n';
951 		break;
952 	    }
953 	    last_ch = c;
954 	    count++;
955 	}
956 	ignored = FALSE;
957 
958 	if (count > MAXCAPLEN && !long_warning) {
959 	    _nc_warning("Very long string found.  Missing separator?");
960 	    long_warning = TRUE;
961 	}
962     }				/* end while */
963 
964     *ptr = '\0';
965 
966     return (c);
967 }
968 
969 /*
970  *	_nc_push_token()
971  *
972  *	Push a token of given type so that it will be reread by the next
973  *	get_token() call.
974  */
975 
976 NCURSES_EXPORT(void)
977 _nc_push_token(int tokclass)
978 {
979     /*
980      * This implementation is kind of bogus, it will fail if we ever do more
981      * than one pushback at a time between get_token() calls.  It relies on the
982      * fact that _nc_curr_token is static storage that nothing but
983      * _nc_get_token() touches.
984      */
985     pushtype = tokclass;
986     if (pushname == 0)
987 	pushname = typeMalloc(char, MAX_NAME_SIZE + 1);
988     _nc_get_type(pushname);
989 
990     DEBUG(3, ("pushing token: `%s', class %d",
991 	      ((_nc_curr_token.tk_name != 0)
992 	       ? _nc_curr_token.tk_name
993 	       : "<null>"),
994 	      pushtype));
995 }
996 
997 /*
998  * Panic mode error recovery - skip everything until a "ch" is found.
999  */
1000 NCURSES_EXPORT(void)
1001 _nc_panic_mode(char ch)
1002 {
1003     for (;;) {
1004 	int c = next_char();
1005 	if (c == ch)
1006 	    return;
1007 	if (c == EOF)
1008 	    return;
1009     }
1010 }
1011 
1012 #if NO_LEAKS
1013 NCURSES_EXPORT(void)
1014 _nc_comp_scan_leaks(void)
1015 {
1016     if (pushname != 0) {
1017 	FreeAndNull(pushname);
1018     }
1019     if (tok_buf != 0) {
1020 	FreeAndNull(tok_buf);
1021     }
1022 }
1023 #endif
1024