xref: /freebsd/contrib/ncurses/ncurses/tinfo/read_termcap.c (revision c98323078dede7579020518ec84cdcb478e5c142)
1 /****************************************************************************
2  * Copyright (c) 1998,1999,2000,2001 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      *
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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   *
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26  * authorization.                                                           *
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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  * Termcap compatibility support
36  *
37  * If your OS integrator didn't install a terminfo database, you can call
38  * _nc_read_termcap_entry() to support reading and translating capabilities
39  * from the system termcap file.  This is a kludge; it will bulk up and slow
40  * down every program that uses ncurses, and translated termcap entries cannot
41  * use full terminfo capabilities.  Don't use it unless you absolutely have to;
42  * instead, get your system people to run tic(1) from root on the terminfo
43  * master included with ncurses to translate it into a terminfo database.
44  *
45  * If USE_GETCAP is enabled, we use what is effectively a copy of the 4.4BSD
46  * getcap code to fetch entries.  There are disadvantages to this; mainly that
47  * getcap(3) does its own resolution, meaning that entries read in in this way
48  * can't reference the terminfo tree.  The only thing it buys is faster startup
49  * time, getcap(3) is much faster than our tic parser.
50  */
51 
52 #include <curses.priv.h>
53 
54 #include <ctype.h>
55 #include <sys/types.h>
56 #include <sys/stat.h>
57 #include <tic.h>
58 #include <term_entry.h>
59 
60 MODULE_ID("$Id: read_termcap.c,v 1.58 2001/10/28 01:11:34 tom Exp $")
61 
62 #if !PURE_TERMINFO
63 
64 #ifdef __EMX__
65 #define is_pathname(s) ((((s) != 0) && ((s)[0] == '/')) \
66 		  || (((s)[0] != 0) && ((s)[1] == ':')))
67 #else
68 #define is_pathname(s) ((s) != 0 && (s)[0] == '/')
69 #endif
70 
71 #define TC_SUCCESS     0
72 #define TC_UNRESOLVED -1
73 #define TC_NOT_FOUND  -2
74 #define TC_SYS_ERR    -3
75 #define TC_REF_LOOP   -4
76 
77 static char *
78 get_termpath(void)
79 {
80     char *result;
81 
82     if (!use_terminfo_vars() || (result = getenv("TERMPATH")) == 0)
83 	result = TERMPATH;
84     T(("TERMPATH is %s", result));
85     return result;
86 }
87 
88 #if USE_GETCAP
89 
90 #if HAVE_BSD_CGETENT
91 #define _nc_cgetcap   cgetcap
92 #define _nc_cgetent(buf, oline, db_array, name) cgetent(buf, db_array, name)
93 #define _nc_cgetmatch cgetmatch
94 #define _nc_cgetset   cgetset
95 #else
96 static int _nc_cgetmatch(char *, const char *);
97 static int _nc_getent(char **, unsigned *, int *, int, char **, int, const char
98 		      *, int, char *);
99 static int _nc_nfcmp(const char *, char *);
100 
101 /*-
102  * Copyright (c) 1992, 1993
103  *	The Regents of the University of California.  All rights reserved.
104  *
105  * This code is derived from software contributed to Berkeley by
106  * Casey Leedom of Lawrence Livermore National Laboratory.
107  *
108  * Redistribution and use in source and binary forms, with or without
109  * modification, are permitted provided that the following conditions
110  * are met:
111  * 1. Redistributions of source code must retain the above copyright
112  *    notice, this list of conditions and the following disclaimer.
113  * 2. Redistributions in binary form must reproduce the above copyright
114  *    notice, this list of conditions and the following disclaimer in the
115  *    documentation and/or other materials provided with the distribution.
116  * 3. All advertising materials mentioning features or use of this software
117  *    must display the following acknowledgment:
118  *	This product includes software developed by the University of
119  *	California, Berkeley and its contributors.
120  * 4. Neither the name of the University nor the names of its contributors
121  *    may be used to endorse or promote products derived from this software
122  *    without specific prior written permission.
123  *
124  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
125  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
126  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
127  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
128  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
129  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
130  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
131  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
132  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
133  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
134  * SUCH DAMAGE.
135  */
136 
137 /* static char sccsid[] = "@(#)getcap.c	8.3 (Berkeley) 3/25/94"; */
138 
139 #define	BFRAG		1024
140 #define	BSIZE		1024
141 #define	MAX_RECURSION	32	/* maximum getent recursion */
142 
143 static size_t topreclen;	/* toprec length */
144 static char *toprec;		/* Additional record specified by cgetset() */
145 static int gottoprec;		/* Flag indicating retrieval of toprecord */
146 
147 /*
148  * Cgetset() allows the addition of a user specified buffer to be added to the
149  * database array, in effect "pushing" the buffer on top of the virtual
150  * database.  0 is returned on success, -1 on failure.
151  */
152 static int
153 _nc_cgetset(const char *ent)
154 {
155     if (ent == 0) {
156 	FreeIfNeeded(toprec);
157 	toprec = 0;
158 	topreclen = 0;
159 	return (0);
160     }
161     topreclen = strlen(ent);
162     if ((toprec = typeMalloc(char, topreclen + 1)) == 0) {
163 	errno = ENOMEM;
164 	return (-1);
165     }
166     gottoprec = 0;
167     (void) strcpy(toprec, ent);
168     return (0);
169 }
170 
171 /*
172  * Cgetcap searches the capability record buf for the capability cap with type
173  * `type'.  A pointer to the value of cap is returned on success, 0 if the
174  * requested capability couldn't be found.
175  *
176  * Specifying a type of ':' means that nothing should follow cap (:cap:).  In
177  * this case a pointer to the terminating ':' or NUL will be returned if cap is
178  * found.
179  *
180  * If (cap, '@') or (cap, terminator, '@') is found before (cap, terminator)
181  * return 0.
182  */
183 static char *
184 _nc_cgetcap(char *buf, const char *cap, int type)
185 {
186     register const char *cp;
187     register char *bp;
188 
189     bp = buf;
190     for (;;) {
191 	/*
192 	 * Skip past the current capability field - it's either the
193 	 * name field if this is the first time through the loop, or
194 	 * the remainder of a field whose name failed to match cap.
195 	 */
196 	for (;;) {
197 	    if (*bp == '\0')
198 		return (0);
199 	    else if (*bp++ == ':')
200 		break;
201 	}
202 
203 	/*
204 	 * Try to match (cap, type) in buf.
205 	 */
206 	for (cp = cap; *cp == *bp && *bp != '\0'; cp++, bp++)
207 	    continue;
208 	if (*cp != '\0')
209 	    continue;
210 	if (*bp == '@')
211 	    return (0);
212 	if (type == ':') {
213 	    if (*bp != '\0' && *bp != ':')
214 		continue;
215 	    return (bp);
216 	}
217 	if (*bp != type)
218 	    continue;
219 	bp++;
220 	return (*bp == '@' ? 0 : bp);
221     }
222     /* NOTREACHED */
223 }
224 
225 /*
226  * Cgetent extracts the capability record name from the NULL terminated file
227  * array db_array and returns a pointer to a malloc'd copy of it in buf.  Buf
228  * must be retained through all subsequent calls to cgetcap, cgetnum, cgetflag,
229  * and cgetstr, but may then be freed.
230  *
231  * Returns:
232  *
233  * positive #    on success (i.e., the index in db_array)
234  * TC_UNRESOLVED if we had too many recurrences to resolve
235  * TC_NOT_FOUND  if the requested record couldn't be found
236  * TC_SYS_ERR    if a system error was encountered (e.g.,couldn't open a file)
237  * TC_REF_LOOP   if a potential reference loop is detected
238  */
239 static int
240 _nc_cgetent(char **buf, int *oline, char **db_array, const char *name)
241 {
242     unsigned dummy;
243 
244     return (_nc_getent(buf, &dummy, oline, 0, db_array, -1, name, 0, 0));
245 }
246 
247 /*
248  * Getent implements the functions of cgetent.  If fd is non-negative,
249  * *db_array has already been opened and fd is the open file descriptor.  We
250  * do this to save time and avoid using up file descriptors for tc=
251  * recursions.
252  *
253  * Getent returns the same success/failure codes as cgetent.  On success, a
254  * pointer to a malloc'd capability record with all tc= capabilities fully
255  * expanded and its length (not including trailing ASCII NUL) are left in
256  * *cap and *len.
257  *
258  * Basic algorithm:
259  *	+ Allocate memory incrementally as needed in chunks of size BFRAG
260  *	  for capability buffer.
261  *	+ Recurse for each tc=name and interpolate result.  Stop when all
262  *	  names interpolated, a name can't be found, or depth exceeds
263  *	  MAX_RECURSION.
264  */
265 #define DOALLOC(size) typeRealloc(char, size, record)
266 static int
267 _nc_getent(
268 	      char **cap,	/* termcap-content */
269 	      unsigned *len,	/* length, needed for recursion */
270 	      int *beginning,	/* line-number at match */
271 	      int in_array,	/* index in 'db_array[] */
272 	      char **db_array,	/* list of files to search */
273 	      int fd,
274 	      const char *name,
275 	      int depth,
276 	      char *nfield)
277 {
278     register char *r_end, *rp;
279     int myfd = FALSE;
280     char *record = 0;
281     int tc_not_resolved;
282     int current;
283     int lineno;
284 
285     /*
286      * Return with ``loop detected'' error if we've recurred more than
287      * MAX_RECURSION times.
288      */
289     if (depth > MAX_RECURSION)
290 	return (TC_REF_LOOP);
291 
292     /*
293      * Check if we have a top record from cgetset().
294      */
295     if (depth == 0 && toprec != 0 && _nc_cgetmatch(toprec, name) == 0) {
296 	if ((record = DOALLOC(topreclen + BFRAG)) == 0) {
297 	    errno = ENOMEM;
298 	    return (TC_SYS_ERR);
299 	}
300 	(void) strcpy(record, toprec);
301 	rp = record + topreclen + 1;
302 	r_end = rp + BFRAG;
303 	current = in_array;
304     } else {
305 	int foundit;
306 
307 	/*
308 	 * Allocate first chunk of memory.
309 	 */
310 	if ((record = DOALLOC(BFRAG)) == 0) {
311 	    errno = ENOMEM;
312 	    return (TC_SYS_ERR);
313 	}
314 	rp = r_end = record + BFRAG;
315 	foundit = FALSE;
316 
317 	/*
318 	 * Loop through database array until finding the record.
319 	 */
320 	for (current = in_array; db_array[current] != 0; current++) {
321 	    int eof = FALSE;
322 
323 	    /*
324 	     * Open database if not already open.
325 	     */
326 	    if (fd >= 0) {
327 		(void) lseek(fd, (off_t) 0, SEEK_SET);
328 	    } else if ((_nc_access(db_array[current], R_OK) < 0)
329 		       || (fd = open(db_array[current], O_RDONLY, 0)) < 0) {
330 		/* No error on unfound file. */
331 		if (errno == ENOENT)
332 		    continue;
333 		free(record);
334 		return (TC_SYS_ERR);
335 	    } else {
336 		myfd = TRUE;
337 	    }
338 	    lineno = 0;
339 
340 	    /*
341 	     * Find the requested capability record ...
342 	     */
343 	    {
344 		char buf[2048];
345 		register char *b_end = buf;
346 		register char *bp = buf;
347 		register int c;
348 
349 		/*
350 		 * Loop invariants:
351 		 *      There is always room for one more character in record.
352 		 *      R_end always points just past end of record.
353 		 *      Rp always points just past last character in record.
354 		 *      B_end always points just past last character in buf.
355 		 *      Bp always points at next character in buf.
356 		 */
357 
358 		for (;;) {
359 		    int first = lineno + 1;
360 
361 		    /*
362 		     * Read in a line implementing (\, newline)
363 		     * line continuation.
364 		     */
365 		    rp = record;
366 		    for (;;) {
367 			if (bp >= b_end) {
368 			    int n;
369 
370 			    n = read(fd, buf, sizeof(buf));
371 			    if (n <= 0) {
372 				if (myfd)
373 				    (void) close(fd);
374 				if (n < 0) {
375 				    free(record);
376 				    return (TC_SYS_ERR);
377 				}
378 				fd = -1;
379 				eof = TRUE;
380 				break;
381 			    }
382 			    b_end = buf + n;
383 			    bp = buf;
384 			}
385 
386 			c = *bp++;
387 			if (c == '\n') {
388 			    lineno++;
389 			    if (rp == record || *(rp - 1) != '\\')
390 				break;
391 			}
392 			*rp++ = c;
393 
394 			/*
395 			 * Enforce loop invariant: if no room
396 			 * left in record buffer, try to get
397 			 * some more.
398 			 */
399 			if (rp >= r_end) {
400 			    unsigned pos;
401 			    size_t newsize;
402 
403 			    pos = rp - record;
404 			    newsize = r_end - record + BFRAG;
405 			    record = DOALLOC(newsize);
406 			    if (record == 0) {
407 				if (myfd)
408 				    (void) close(fd);
409 				errno = ENOMEM;
410 				return (TC_SYS_ERR);
411 			    }
412 			    r_end = record + newsize;
413 			    rp = record + pos;
414 			}
415 		    }
416 		    /* loop invariant lets us do this */
417 		    *rp++ = '\0';
418 
419 		    /*
420 		     * If encountered eof check next file.
421 		     */
422 		    if (eof)
423 			break;
424 
425 		    /*
426 		     * Toss blank lines and comments.
427 		     */
428 		    if (*record == '\0' || *record == '#')
429 			continue;
430 
431 		    /*
432 		     * See if this is the record we want ...
433 		     */
434 		    if (_nc_cgetmatch(record, name) == 0
435 			&& (nfield == 0
436 			    || !_nc_nfcmp(nfield, record))) {
437 			foundit = TRUE;
438 			*beginning = first;
439 			break;	/* found it! */
440 		    }
441 		}
442 	    }
443 	    if (foundit)
444 		break;
445 	}
446 
447 	if (!foundit)
448 	    return (TC_NOT_FOUND);
449     }
450 
451     /*
452      * Got the capability record, but now we have to expand all tc=name
453      * references in it ...
454      */
455     {
456 	register char *newicap, *s;
457 	register int newilen;
458 	unsigned ilen;
459 	int diff, iret, tclen, oline;
460 	char *icap, *scan, *tc, *tcstart, *tcend;
461 
462 	/*
463 	 * Loop invariants:
464 	 *      There is room for one more character in record.
465 	 *      R_end points just past end of record.
466 	 *      Rp points just past last character in record.
467 	 *      Scan points at remainder of record that needs to be
468 	 *      scanned for tc=name constructs.
469 	 */
470 	scan = record;
471 	tc_not_resolved = FALSE;
472 	for (;;) {
473 	    if ((tc = _nc_cgetcap(scan, "tc", '=')) == 0)
474 		break;
475 
476 	    /*
477 	     * Find end of tc=name and stomp on the trailing `:'
478 	     * (if present) so we can use it to call ourselves.
479 	     */
480 	    s = tc;
481 	    while (*s != '\0') {
482 		if (*s++ == ':') {
483 		    *(s - 1) = '\0';
484 		    break;
485 		}
486 	    }
487 	    tcstart = tc - 3;
488 	    tclen = s - tcstart;
489 	    tcend = s;
490 
491 	    iret = _nc_getent(&icap, &ilen, &oline, current, db_array, fd,
492 			      tc, depth + 1, 0);
493 	    newicap = icap;	/* Put into a register. */
494 	    newilen = ilen;
495 	    if (iret != TC_SUCCESS) {
496 		/* an error */
497 		if (iret < TC_NOT_FOUND) {
498 		    if (myfd)
499 			(void) close(fd);
500 		    free(record);
501 		    return (iret);
502 		}
503 		if (iret == TC_UNRESOLVED)
504 		    tc_not_resolved = TRUE;
505 		/* couldn't resolve tc */
506 		if (iret == TC_NOT_FOUND) {
507 		    *(s - 1) = ':';
508 		    scan = s - 1;
509 		    tc_not_resolved = TRUE;
510 		    continue;
511 		}
512 	    }
513 
514 	    /* not interested in name field of tc'ed record */
515 	    s = newicap;
516 	    while (*s != '\0' && *s++ != ':') ;
517 	    newilen -= s - newicap;
518 	    newicap = s;
519 
520 	    /* make sure interpolated record is `:'-terminated */
521 	    s += newilen;
522 	    if (*(s - 1) != ':') {
523 		*s = ':';	/* overwrite NUL with : */
524 		newilen++;
525 	    }
526 
527 	    /*
528 	     * Make sure there's enough room to insert the
529 	     * new record.
530 	     */
531 	    diff = newilen - tclen;
532 	    if (diff >= r_end - rp) {
533 		unsigned pos, tcpos, tcposend;
534 		size_t newsize;
535 
536 		pos = rp - record;
537 		newsize = r_end - record + diff + BFRAG;
538 		tcpos = tcstart - record;
539 		tcposend = tcend - record;
540 		record = DOALLOC(newsize);
541 		if (record == 0) {
542 		    if (myfd)
543 			(void) close(fd);
544 		    free(icap);
545 		    errno = ENOMEM;
546 		    return (TC_SYS_ERR);
547 		}
548 		r_end = record + newsize;
549 		rp = record + pos;
550 		tcstart = record + tcpos;
551 		tcend = record + tcposend;
552 	    }
553 
554 	    /*
555 	     * Insert tc'ed record into our record.
556 	     */
557 	    s = tcstart + newilen;
558 	    memmove(s, tcend, (size_t) (rp - tcend));
559 	    memmove(tcstart, newicap, (size_t) newilen);
560 	    rp += diff;
561 	    free(icap);
562 
563 	    /*
564 	     * Start scan on `:' so next cgetcap works properly
565 	     * (cgetcap always skips first field).
566 	     */
567 	    scan = s - 1;
568 	}
569     }
570 
571     /*
572      * Close file (if we opened it), give back any extra memory, and
573      * return capability, length and success.
574      */
575     if (myfd)
576 	(void) close(fd);
577     *len = rp - record - 1;	/* don't count NUL */
578     if (r_end > rp) {
579 	if ((record = DOALLOC((size_t) (rp - record))) == 0) {
580 	    errno = ENOMEM;
581 	    return (TC_SYS_ERR);
582 	}
583     }
584 
585     *cap = record;
586     if (tc_not_resolved)
587 	return (TC_UNRESOLVED);
588     return (current);
589 }
590 
591 /*
592  * Cgetmatch will return 0 if name is one of the names of the capability
593  * record buf, -1 if not.
594  */
595 static int
596 _nc_cgetmatch(char *buf, const char *name)
597 {
598     register const char *np;
599     register char *bp;
600 
601     /*
602      * Start search at beginning of record.
603      */
604     bp = buf;
605     for (;;) {
606 	/*
607 	 * Try to match a record name.
608 	 */
609 	np = name;
610 	for (;;) {
611 	    if (*np == '\0') {
612 		if (*bp == '|' || *bp == ':' || *bp == '\0')
613 		    return (0);
614 		else
615 		    break;
616 	    } else if (*bp++ != *np++) {
617 		break;
618 	    }
619 	}
620 
621 	/*
622 	 * Match failed, skip to next name in record.
623 	 */
624 	bp--;			/* a '|' or ':' may have stopped the match */
625 	for (;;) {
626 	    if (*bp == '\0' || *bp == ':')
627 		return (-1);	/* match failed totally */
628 	    else if (*bp++ == '|')
629 		break;		/* found next name */
630 	}
631     }
632 }
633 
634 /*
635  * Compare name field of record.
636  */
637 static int
638 _nc_nfcmp(const char *nf, char *rec)
639 {
640     char *cp, tmp;
641     int ret;
642 
643     for (cp = rec; *cp != ':'; cp++) ;
644 
645     tmp = *(cp + 1);
646     *(cp + 1) = '\0';
647     ret = strcmp(nf, rec);
648     *(cp + 1) = tmp;
649 
650     return (ret);
651 }
652 #endif /* HAVE_BSD_CGETENT */
653 
654 /*
655  * Since ncurses provides its own 'tgetent()', we cannot use the native one.
656  * So we reproduce the logic to get down to cgetent() -- or our cut-down
657  * version of that -- to circumvent the problem of configuring against the
658  * termcap library.
659  */
660 #define USE_BSD_TGETENT 1
661 
662 #if USE_BSD_TGETENT
663 /*
664  * Copyright (c) 1980, 1993
665  *	The Regents of the University of California.  All rights reserved.
666  *
667  * Redistribution and use in source and binary forms, with or without
668  * modification, are permitted provided that the following conditions
669  * are met:
670  * 1. Redistributions of source code must retain the above copyright
671  *    notice, this list of conditions and the following disclaimer.
672  * 2. Redistributions in binary form must reproduce the above copyright
673  *    notice, this list of conditions and the following disclaimer in the
674  *    documentation and/or other materials provided with the distribution.
675  * 3. All advertising materials mentioning features or use of this software
676  *    must display the following acknowledgment:
677  *	This product includes software developed by the University of
678  *	California, Berkeley and its contributors.
679  * 4. Neither the name of the University nor the names of its contributors
680  *    may be used to endorse or promote products derived from this software
681  *    without specific prior written permission.
682  *
683  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
684  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
685  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
686  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
687  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
688  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
689  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
690  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
691  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
692  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
693  * SUCH DAMAGE.
694  */
695 
696 /* static char sccsid[] = "@(#)termcap.c	8.1 (Berkeley) 6/4/93" */
697 
698 #define	PBUFSIZ		512	/* max length of filename path */
699 #define	PVECSIZ		32	/* max number of names in path */
700 #define TBUFSIZ (2048*2)
701 
702 static char *tbuf;
703 
704 /*
705  * On entry, srcp points to a non ':' character which is the beginning of the
706  * token, if any.  We'll try to return a string that doesn't end with a ':'.
707  */
708 static char *
709 get_tc_token(char **srcp, int *endp)
710 {
711     int ch;
712     bool found = FALSE;
713     char *s, *base;
714     char *tok = 0;
715 
716     *endp = TRUE;
717     for (s = base = *srcp; *s != '\0';) {
718 	ch = *s++;
719 	if (ch == '\\') {
720 	    if (*s == '\0') {
721 		break;
722 	    } else if (*s++ == '\n') {
723 		while (isspace(*s))
724 		    s++;
725 	    } else {
726 		found = TRUE;
727 	    }
728 	} else if (ch == ':') {
729 	    if (found) {
730 		tok = base;
731 		s[-1] = '\0';
732 		*srcp = s;
733 		*endp = FALSE;
734 		break;
735 	    }
736 	    base = s;
737 	} else if (isgraph(ch)) {
738 	    found = TRUE;
739 	}
740     }
741 
742     /* malformed entry may end without a ':' */
743     if (tok == 0 && found) {
744 	tok = base;
745     }
746 
747     return tok;
748 }
749 
750 static char *
751 copy_tc_token(char *dst, const char *src, size_t len)
752 {
753     int ch;
754 
755     while ((ch = *src++) != '\0') {
756 	if (ch == '\\' && *src == '\n') {
757 	    while (isspace(*src))
758 		src++;
759 	    continue;
760 	}
761 	if (--len == 0) {
762 	    dst = 0;
763 	    break;
764 	}
765 	*dst++ = ch;
766     }
767     return dst;
768 }
769 
770 /*
771  * Get an entry for terminal name in buffer bp from the termcap file.
772  */
773 static int
774 _nc_tgetent(char *bp, char **sourcename, int *lineno, const char *name)
775 {
776     static char *the_source;
777 
778     register char *p;
779     register char *cp;
780     char *dummy = NULL;
781     char **fname;
782     char *home;
783     int i;
784     char pathbuf[PBUFSIZ];	/* holds raw path of filenames */
785     char *pathvec[PVECSIZ];	/* to point to names in pathbuf */
786     char **pvec;		/* holds usable tail of path vector */
787     char *termpath;
788     string_desc desc;
789 
790     fname = pathvec;
791     pvec = pathvec;
792     tbuf = bp;
793     p = pathbuf;
794     cp = use_terminfo_vars()? getenv("TERMCAP") : NULL;
795 
796     /*
797      * TERMCAP can have one of two things in it.  It can be the name of a file
798      * to use instead of /etc/termcap.  In this case it better start with a
799      * "/".  Or it can be an entry to use so we don't have to read the file.
800      * In this case it has to already have the newlines crunched out.  If
801      * TERMCAP does not hold a file name then a path of names is searched
802      * instead.  The path is found in the TERMPATH variable, or becomes
803      * "$HOME/.termcap /etc/termcap" if no TERMPATH exists.
804      */
805     _nc_str_init(&desc, pathbuf, sizeof(pathbuf));
806     if (cp == NULL) {
807 	_nc_safe_strcpy(&desc, get_termpath());
808     } else if (!is_pathname(cp)) {	/* TERMCAP holds an entry */
809 	if ((termpath = get_termpath()) != 0) {
810 	    _nc_safe_strcat(&desc, termpath);
811 	} else {
812 	    char temp[PBUFSIZ];
813 	    temp[0] = 0;
814 	    if ((home = getenv("HOME")) != 0 && *home != '\0'
815 		&& strchr(home, ' ') == 0
816 		&& strlen(home) < sizeof(temp) - 10) {	/* setup path */
817 		sprintf(temp, "%s/", home);	/* $HOME first */
818 	    }
819 	    /* if no $HOME look in current directory */
820 	    strcat(temp, ".termcap");
821 	    _nc_safe_strcat(&desc, temp);
822 	    _nc_safe_strcat(&desc, " ");
823 	    _nc_safe_strcat(&desc, get_termpath());
824 	}
825     } else {			/* user-defined name in TERMCAP */
826 	_nc_safe_strcat(&desc, cp);	/* still can be tokenized */
827     }
828 
829     *fname++ = pathbuf;		/* tokenize path into vector of names */
830     while (*++p) {
831 	if (*p == ' ' || *p == NCURSES_PATHSEP) {
832 	    *p = '\0';
833 	    while (*++p)
834 		if (*p != ' ' && *p != NCURSES_PATHSEP)
835 		    break;
836 	    if (*p == '\0')
837 		break;
838 	    *fname++ = p;
839 	    if (fname >= pathvec + PVECSIZ) {
840 		fname--;
841 		break;
842 	    }
843 	}
844     }
845     *fname = 0;			/* mark end of vector */
846     if (is_pathname(cp)) {
847 	if (_nc_cgetset(cp) < 0) {
848 	    return (TC_SYS_ERR);
849 	}
850     }
851 
852     i = _nc_cgetent(&dummy, lineno, pathvec, name);
853 
854     /* ncurses' termcap-parsing routines cannot handle multiple adjacent
855      * empty fields, and mistakenly use the last valid cap entry instead of
856      * the first (breaks tc= includes)
857      */
858     if (i >= 0) {
859 	char *pd, *ps, *tok;
860 	int endflag = FALSE;
861 	char *list[1023];
862 	size_t n, count = 0;
863 
864 	pd = bp;
865 	ps = dummy;
866 	while (!endflag && (tok = get_tc_token(&ps, &endflag)) != 0) {
867 	    bool ignore = FALSE;
868 
869 	    for (n = 1; n < count; n++) {
870 		char *s = list[n];
871 		if (s[0] == tok[0]
872 		    && s[1] == tok[1]) {
873 		    ignore = TRUE;
874 		    break;
875 		}
876 	    }
877 	    if (ignore != TRUE) {
878 		list[count++] = tok;
879 		pd = copy_tc_token(pd, tok, TBUFSIZ - (2 + pd - bp));
880 		if (pd == 0) {
881 		    i = -1;
882 		    break;
883 		}
884 		*pd++ = ':';
885 		*pd = '\0';
886 	    }
887 	}
888     }
889 
890     FreeIfNeeded(dummy);
891     FreeIfNeeded(the_source);
892     the_source = 0;
893 
894     /* This is not related to the BSD cgetent(), but to fake up a suitable
895      * filename for ncurses' error reporting.  (If we are not using BSD
896      * cgetent, then it is the actual filename).
897      */
898     if (i >= 0) {
899 	if ((the_source = strdup(pathvec[i])) != 0)
900 	    *sourcename = the_source;
901     }
902 
903     return (i);
904 }
905 #endif /* USE_BSD_TGETENT */
906 #endif /* USE_GETCAP */
907 
908 #define MAXPATHS	32
909 
910 /*
911  * Add a filename to the list in 'termpaths[]', checking that we really have
912  * a right to open the file.
913  */
914 #if !USE_GETCAP
915 static int
916 add_tc(char *termpaths[], char *path, int count)
917 {
918     char *save = strchr(path, NCURSES_PATHSEP);
919     if (save != 0)
920 	*save = '\0';
921     if (count < MAXPATHS
922 	&& _nc_access(path, R_OK) == 0) {
923 	termpaths[count++] = path;
924 	T(("Adding termpath %s", path));
925     }
926     termpaths[count] = 0;
927     if (save != 0)
928 	*save = NCURSES_PATHSEP;
929     return count;
930 }
931 #define ADD_TC(path, count) filecount = add_tc(termpaths, path, count)
932 #endif /* !USE_GETCAP */
933 
934 NCURSES_EXPORT(int)
935 _nc_read_termcap_entry(const char *const tn, TERMTYPE * const tp)
936 {
937     int found = FALSE;
938     ENTRY *ep;
939 #if USE_GETCAP_CACHE
940     char cwd_buf[PATH_MAX];
941 #endif
942 #if USE_GETCAP
943     char *p, tc[TBUFSIZ];
944     static char *source;
945     static int lineno;
946 
947     T(("read termcap entry for %s", tn));
948     if (use_terminfo_vars() && (p = getenv("TERMCAP")) != 0
949 	&& !is_pathname(p) && _nc_name_match(p, tn, "|:")) {
950 	/* TERMCAP holds a termcap entry */
951 	strncpy(tc, p, sizeof(tc) - 1);
952 	tc[sizeof(tc) - 1] = '\0';
953 	_nc_set_source("TERMCAP");
954     } else {
955 	/* we're using getcap(3) */
956 	if (_nc_tgetent(tc, &source, &lineno, tn) < 0)
957 	    return (ERR);
958 
959 	_nc_curr_line = lineno;
960 	_nc_set_source(source);
961     }
962     _nc_read_entry_source((FILE *) 0, tc, FALSE, FALSE, NULLHOOK);
963 #else
964     /*
965      * Here is what the 4.4BSD termcap(3) page prescribes:
966      *
967      * It will look in the environment for a TERMCAP variable.  If found, and
968      * the value does not begin with a slash, and the terminal type name is the
969      * same as the environment string TERM, the TERMCAP string is used instead
970      * of reading a termcap file.  If it does begin with a slash, the string is
971      * used as a path name of the termcap file to search.  If TERMCAP does not
972      * begin with a slash and name is different from TERM, tgetent() searches
973      * the files $HOME/.termcap and /usr/share/misc/termcap, in that order,
974      * unless the environment variable TERMPATH exists, in which case it
975      * specifies a list of file pathnames (separated by spaces or colons) to be
976      * searched instead.
977      *
978      * It goes on to state:
979      *
980      * Whenever multiple files are searched and a tc field occurs in the
981      * requested entry, the entry it names must be found in the same file or
982      * one of the succeeding files.
983      *
984      * However, this restriction is relaxed in ncurses; tc references to
985      * previous files are permitted.
986      *
987      * This routine returns 1 if an entry is found, 0 if not found, and -1 if
988      * the database is not accessible.
989      */
990     FILE *fp;
991     char *tc, *termpaths[MAXPATHS];
992     int filecount = 0;
993     int j, k;
994     bool use_buffer = FALSE;
995     bool normal = TRUE;
996     char tc_buf[1024];
997     char pathbuf[PATH_MAX];
998     char *copied = 0;
999     char *cp;
1000     struct stat test_stat[MAXPATHS];
1001 
1002     termpaths[filecount] = 0;
1003     if (use_terminfo_vars() && (tc = getenv("TERMCAP")) != 0) {
1004 	if (is_pathname(tc)) {	/* interpret as a filename */
1005 	    ADD_TC(tc, 0);
1006 	    normal = FALSE;
1007 	} else if (_nc_name_match(tc, tn, "|:")) {	/* treat as a capability file */
1008 	    use_buffer = TRUE;
1009 	    (void) sprintf(tc_buf, "%.*s\n", (int) sizeof(tc_buf) - 2, tc);
1010 	    normal = FALSE;
1011 	}
1012     }
1013 
1014     if (normal) {		/* normal case */
1015 	char envhome[PATH_MAX], *h;
1016 
1017 	copied = strdup(get_termpath());
1018 	for (cp = copied; *cp; cp++) {
1019 	    if (*cp == NCURSES_PATHSEP)
1020 		*cp = '\0';
1021 	    else if (cp == copied || cp[-1] == '\0') {
1022 		ADD_TC(cp, filecount);
1023 	    }
1024 	}
1025 
1026 #define PRIVATE_CAP "%s/.termcap"
1027 
1028 	if (use_terminfo_vars() && (h = getenv("HOME")) != NULL && *h != '\0'
1029 	    && (strlen(h) + sizeof(PRIVATE_CAP)) < PATH_MAX) {
1030 	    /* user's .termcap, if any, should override it */
1031 	    (void) strcpy(envhome, h);
1032 	    (void) sprintf(pathbuf, PRIVATE_CAP, envhome);
1033 	    ADD_TC(pathbuf, filecount);
1034 	}
1035     }
1036 
1037     /*
1038      * Probably /etc/termcap is a symlink to /usr/share/misc/termcap.
1039      * Avoid reading the same file twice.
1040      */
1041 #ifdef HAVE_LINK
1042     for (j = 0; j < filecount; j++) {
1043 	bool omit = FALSE;
1044 	if (stat(termpaths[j], &test_stat[j]) != 0
1045 	    || (test_stat[j].st_mode & S_IFMT) != S_IFREG) {
1046 	    omit = TRUE;
1047 	} else {
1048 	    for (k = 0; k < j; k++) {
1049 		if (test_stat[k].st_dev == test_stat[j].st_dev
1050 		    && test_stat[k].st_ino == test_stat[j].st_ino) {
1051 		    omit = TRUE;
1052 		    break;
1053 		}
1054 	    }
1055 	}
1056 	if (omit) {
1057 	    T(("Path %s is a duplicate", termpaths[j]));
1058 	    for (k = j + 1; k < filecount; k++) {
1059 		termpaths[k - 1] = termpaths[k];
1060 		test_stat[k - 1] = test_stat[k];
1061 	    }
1062 	    --filecount;
1063 	    --j;
1064 	}
1065     }
1066 #endif
1067 
1068     /* parse the sources */
1069     if (use_buffer) {
1070 	_nc_set_source("TERMCAP");
1071 
1072 	/*
1073 	 * We don't suppress warning messages here.  The presumption is
1074 	 * that since it's just a single entry, they won't be a pain.
1075 	 */
1076 	_nc_read_entry_source((FILE *) 0, tc_buf, FALSE, FALSE, NULLHOOK);
1077     } else {
1078 	int i;
1079 
1080 	for (i = 0; i < filecount; i++) {
1081 
1082 	    T(("Looking for %s in %s", tn, termpaths[i]));
1083 	    if (_nc_access(termpaths[i], R_OK) == 0
1084 		&& (fp = fopen(termpaths[i], "r")) != (FILE *) 0) {
1085 		_nc_set_source(termpaths[i]);
1086 
1087 		/*
1088 		 * Suppress warning messages.  Otherwise you get 400 lines of
1089 		 * crap from archaic termcap files as ncurses complains about
1090 		 * all the obsolete capabilities.
1091 		 */
1092 		_nc_read_entry_source(fp, (char *) 0, FALSE, TRUE, NULLHOOK);
1093 
1094 		(void) fclose(fp);
1095 	    }
1096 	}
1097     }
1098     if (copied != 0)
1099 	free(copied);
1100 #endif /* USE_GETCAP */
1101 
1102     if (_nc_head == 0)
1103 	return (ERR);
1104 
1105     /* resolve all use references */
1106     _nc_resolve_uses(TRUE);
1107 
1108     /* find a terminal matching tn, if we can */
1109 #if USE_GETCAP_CACHE
1110     if (getcwd(cwd_buf, sizeof(cwd_buf)) != 0) {
1111 	_nc_set_writedir((char *) 0);	/* note: this does a chdir */
1112 #endif
1113 	for_entry_list(ep) {
1114 	    if (_nc_name_match(ep->tterm.term_names, tn, "|:")) {
1115 		/*
1116 		 * Make a local copy of the terminal capabilities.  Free all
1117 		 * entry storage except the string table for the loaded type
1118 		 * (which we disconnected from the list by NULLing out
1119 		 * ep->tterm.str_table above).
1120 		 */
1121 		*tp = ep->tterm;
1122 		ep->tterm.str_table = (char *) 0;
1123 
1124 		/*
1125 		 * OK, now try to write the type to user's terminfo directory.
1126 		 * Next time he loads this, it will come through terminfo.
1127 		 *
1128 		 * Advantage:  Second and subsequent fetches of this entry will
1129 		 * be very fast.
1130 		 *
1131 		 * Disadvantage:  After the first time a termcap type is loaded
1132 		 * by its user, editing it in the /etc/termcap file, or in
1133 		 * TERMCAP, or in a local ~/.termcap, will be ineffective
1134 		 * unless the terminfo entry is explicitly removed.
1135 		 */
1136 #if USE_GETCAP_CACHE
1137 		(void) _nc_write_entry(tp);
1138 #endif
1139 		found = TRUE;
1140 		break;
1141 	    }
1142 	}
1143 #if USE_GETCAP_CACHE
1144 	chdir(cwd_buf);
1145     }
1146 #endif
1147 
1148     _nc_free_entries(_nc_head);
1149     return (found);
1150 }
1151 #else
1152 extern
1153 NCURSES_EXPORT(void)
1154 _nc_read_termcap(void);
1155 NCURSES_EXPORT(void)
1156 _nc_read_termcap(void)
1157 {
1158 }
1159 #endif /* PURE_TERMINFO */
1160