1 /****************************************************************************
2  * Copyright © 2013                                                         *
3  *	Thorsten “mirabilos” Glaser <tg@mirbsd.org>                         *
4  * Copyright (c) 1998-2004,2005 Free Software Foundation, Inc.              *
5  *                                                                          *
6  * Permission is hereby granted, free of charge, to any person obtaining a  *
7  * copy of this software and associated documentation files (the            *
8  * "Software"), to deal in the Software without restriction, including      *
9  * without limitation the rights to use, copy, modify, merge, publish,      *
10  * distribute, distribute with modifications, sublicense, and/or sell       *
11  * copies of the Software, and to permit persons to whom the Software is    *
12  * furnished to do so, subject to the following conditions:                 *
13  *                                                                          *
14  * The above copyright notice and this permission notice shall be included  *
15  * in all copies or substantial portions of the Software.                   *
16  *                                                                          *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
20  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
21  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
22  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
23  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
24  *                                                                          *
25  * Except as contained in this notice, the name(s) of the above copyright   *
26  * holders shall not be used in advertising or otherwise to promote the     *
27  * sale, use or other dealings in this Software without prior written       *
28  * authorization.                                                           *
29  ****************************************************************************/
30 
31 /****************************************************************************
32  *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
33  *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
34  *     and: Thomas E. Dickey                        1996-on                 *
35  ****************************************************************************/
36 
37 /*
38  * Termcap compatibility support
39  *
40  * If your OS integrator didn't install a terminfo database, you can call
41  * _nc_read_termcap_entry() to support reading and translating capabilities
42  * from the system termcap file.  This is a kludge; it will bulk up and slow
43  * down every program that uses ncurses, and translated termcap entries cannot
44  * use full terminfo capabilities.  Don't use it unless you absolutely have to;
45  * instead, get your system people to run tic(1) from root on the terminfo
46  * master included with ncurses to translate it into a terminfo database.
47  *
48  * If USE_GETCAP is enabled, we use what is effectively a copy of the 4.4BSD
49  * getcap code to fetch entries.  There are disadvantages to this; mainly that
50  * getcap(3) does its own resolution, meaning that entries read in in this way
51  * can't reference the terminfo tree.  The only thing it buys is faster startup
52  * time, getcap(3) is much faster than our tic parser.
53  */
54 
55 #include <curses.priv.h>
56 
57 #include <ctype.h>
58 #include <sys/types.h>
59 #include <sys/stat.h>
60 #include <tic.h>
61 #include <term_entry.h>
62 
63 MODULE_ID("$Id: read_termcap.c,v 1.67 2005/06/04 21:49:20 tom Exp $")
64 #ifdef __MirBSD__
65 __RCSID("$MirOS: src/lib/libncurses/src/ncurses/tinfo/read_termcap.c,v 1.5 2013/10/31 20:06:36 tg Exp $");
66 #endif
67 
68 #if !PURE_TERMINFO
69 
70 #if defined(__EMX__) || defined(__DJGPP__)
71 #define is_pathname(s) ((((s) != 0) && ((s)[0] == '/')) \
72 		  || (((s)[0] != 0) && ((s)[1] == ':')))
73 #else
74 #define is_pathname(s) ((s) != 0 && (s)[0] == '/')
75 #endif
76 
77 #define TC_SUCCESS     0
78 #define TC_UNRESOLVED -1
79 #define TC_NOT_FOUND  -2
80 #define TC_SYS_ERR    -3
81 #define TC_REF_LOOP   -4
82 
83 static NCURSES_CONST char *
get_termpath(void)84 get_termpath(void)
85 {
86     NCURSES_CONST char *result;
87 
88     if (!use_terminfo_vars() || (result = getenv("TERMPATH")) == 0)
89 	result = TERMPATH;
90     T(("TERMPATH is %s", result));
91     return result;
92 }
93 
94 #if USE_GETCAP
95 
96 #if HAVE_BSD_CGETENT
97 #define _nc_cgetcap   cgetcap
98 #define _nc_cgetent(buf, oline, db_array, name) cgetent(buf, db_array, name)
99 #define _nc_cgetmatch cgetmatch
100 #define _nc_cgetset   cgetset
101 #else
102 static int _nc_cgetmatch(char *, const char *);
103 static int _nc_getent(char **, unsigned *, int *, int, char **, int, const char
104 		      *, int, char *);
105 static int _nc_nfcmp(const char *, char *);
106 
107 /*-
108  * Copyright (c) 1992, 1993
109  *	The Regents of the University of California.  All rights reserved.
110  *
111  * This code is derived from software contributed to Berkeley by
112  * Casey Leedom of Lawrence Livermore National Laboratory.
113  *
114  * Redistribution and use in source and binary forms, with or without
115  * modification, are permitted provided that the following conditions
116  * are met:
117  * 1. Redistributions of source code must retain the above copyright
118  *    notice, this list of conditions and the following disclaimer.
119  * 2. Redistributions in binary form must reproduce the above copyright
120  *    notice, this list of conditions and the following disclaimer in the
121  *    documentation and/or other materials provided with the distribution.
122  * 3. All advertising materials mentioning features or use of this software
123  *    must display the following acknowledgment:
124  *	This product includes software developed by the University of
125  *	California, Berkeley and its contributors.
126  * 4. Neither the name of the University nor the names of its contributors
127  *    may be used to endorse or promote products derived from this software
128  *    without specific prior written permission.
129  *
130  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
131  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
132  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
133  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
134  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
135  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
136  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
137  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
138  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
139  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
140  * SUCH DAMAGE.
141  */
142 
143 /* static char sccsid[] = "@(#)getcap.c	8.3 (Berkeley) 3/25/94"; */
144 
145 #define	BFRAG		1024
146 #define	BSIZE		1024
147 #define	MAX_RECURSION	32	/* maximum getent recursion */
148 
149 static size_t topreclen;	/* toprec length */
150 static char *toprec;		/* Additional record specified by cgetset() */
151 static int gottoprec;		/* Flag indicating retrieval of toprecord */
152 
153 /*
154  * Cgetset() allows the addition of a user specified buffer to be added to the
155  * database array, in effect "pushing" the buffer on top of the virtual
156  * database.  0 is returned on success, -1 on failure.
157  */
158 static int
_nc_cgetset(const char * ent)159 _nc_cgetset(const char *ent)
160 {
161     if (ent == 0) {
162 	FreeIfNeeded(toprec);
163 	toprec = 0;
164 	topreclen = 0;
165 	return (0);
166     }
167     topreclen = strlen(ent);
168     if ((toprec = typeMalloc(char, topreclen + 1)) == 0) {
169 	errno = ENOMEM;
170 	return (-1);
171     }
172     gottoprec = 0;
173     (void) strcpy(toprec, ent);
174     return (0);
175 }
176 
177 /*
178  * Cgetcap searches the capability record buf for the capability cap with type
179  * `type'.  A pointer to the value of cap is returned on success, 0 if the
180  * requested capability couldn't be found.
181  *
182  * Specifying a type of ':' means that nothing should follow cap (:cap:).  In
183  * this case a pointer to the terminating ':' or NUL will be returned if cap is
184  * found.
185  *
186  * If (cap, '@') or (cap, terminator, '@') is found before (cap, terminator)
187  * return 0.
188  */
189 static char *
_nc_cgetcap(char * buf,const char * cap,int type)190 _nc_cgetcap(char *buf, const char *cap, int type)
191 {
192     register const char *cp;
193     register char *bp;
194 
195     bp = buf;
196     for (;;) {
197 	/*
198 	 * Skip past the current capability field - it's either the
199 	 * name field if this is the first time through the loop, or
200 	 * the remainder of a field whose name failed to match cap.
201 	 */
202 	for (;;) {
203 	    if (*bp == '\0')
204 		return (0);
205 	    else if (*bp++ == ':')
206 		break;
207 	}
208 
209 	/*
210 	 * Try to match (cap, type) in buf.
211 	 */
212 	for (cp = cap; *cp == *bp && *bp != '\0'; cp++, bp++)
213 	    continue;
214 	if (*cp != '\0')
215 	    continue;
216 	if (*bp == '@')
217 	    return (0);
218 	if (type == ':') {
219 	    if (*bp != '\0' && *bp != ':')
220 		continue;
221 	    return (bp);
222 	}
223 	if (*bp != type)
224 	    continue;
225 	bp++;
226 	return (*bp == '@' ? 0 : bp);
227     }
228     /* NOTREACHED */
229 }
230 
231 /*
232  * Cgetent extracts the capability record name from the NULL terminated file
233  * array db_array and returns a pointer to a malloc'd copy of it in buf.  Buf
234  * must be retained through all subsequent calls to cgetcap, cgetnum, cgetflag,
235  * and cgetstr, but may then be freed.
236  *
237  * Returns:
238  *
239  * positive #    on success (i.e., the index in db_array)
240  * TC_UNRESOLVED if we had too many recurrences to resolve
241  * TC_NOT_FOUND  if the requested record couldn't be found
242  * TC_SYS_ERR    if a system error was encountered (e.g.,couldn't open a file)
243  * TC_REF_LOOP   if a potential reference loop is detected
244  */
245 static int
_nc_cgetent(char ** buf,int * oline,char ** db_array,const char * name)246 _nc_cgetent(char **buf, int *oline, char **db_array, const char *name)
247 {
248     unsigned dummy;
249 
250     return (_nc_getent(buf, &dummy, oline, 0, db_array, -1, name, 0, 0));
251 }
252 
253 /*
254  * Getent implements the functions of cgetent.  If fd is non-negative,
255  * *db_array has already been opened and fd is the open file descriptor.  We
256  * do this to save time and avoid using up file descriptors for tc=
257  * recursions.
258  *
259  * Getent returns the same success/failure codes as cgetent.  On success, a
260  * pointer to a malloc'd capability record with all tc= capabilities fully
261  * expanded and its length (not including trailing ASCII NUL) are left in
262  * *cap and *len.
263  *
264  * Basic algorithm:
265  *	+ Allocate memory incrementally as needed in chunks of size BFRAG
266  *	  for capability buffer.
267  *	+ Recurse for each tc=name and interpolate result.  Stop when all
268  *	  names interpolated, a name can't be found, or depth exceeds
269  *	  MAX_RECURSION.
270  */
271 #define DOALLOC(size) typeRealloc(char, size, record)
272 static int
_nc_getent(char ** cap,unsigned * len,int * beginning,int in_array,char ** db_array,int fd,const char * name,int depth,char * nfield)273 _nc_getent(
274 	      char **cap,	/* termcap-content */
275 	      unsigned *len,	/* length, needed for recursion */
276 	      int *beginning,	/* line-number at match */
277 	      int in_array,	/* index in 'db_array[] */
278 	      char **db_array,	/* list of files to search */
279 	      int fd,
280 	      const char *name,
281 	      int depth,
282 	      char *nfield)
283 {
284     register char *r_end, *rp;
285     int myfd = FALSE;
286     char *record = 0;
287     int tc_not_resolved;
288     int current;
289     int lineno;
290 
291     /*
292      * Return with ``loop detected'' error if we've recurred more than
293      * MAX_RECURSION times.
294      */
295     if (depth > MAX_RECURSION)
296 	return (TC_REF_LOOP);
297 
298     /*
299      * Check if we have a top record from cgetset().
300      */
301     if (depth == 0 && toprec != 0 && _nc_cgetmatch(toprec, name) == 0) {
302 	if ((record = DOALLOC(topreclen + BFRAG)) == 0) {
303 	    errno = ENOMEM;
304 	    return (TC_SYS_ERR);
305 	}
306 	(void) strcpy(record, toprec);
307 	rp = record + topreclen + 1;
308 	r_end = rp + BFRAG;
309 	current = in_array;
310     } else {
311 	int foundit;
312 
313 	/*
314 	 * Allocate first chunk of memory.
315 	 */
316 	if ((record = DOALLOC(BFRAG)) == 0) {
317 	    errno = ENOMEM;
318 	    return (TC_SYS_ERR);
319 	}
320 	rp = r_end = record + BFRAG;
321 	foundit = FALSE;
322 
323 	/*
324 	 * Loop through database array until finding the record.
325 	 */
326 	for (current = in_array; db_array[current] != 0; current++) {
327 	    int eof = FALSE;
328 
329 	    /*
330 	     * Open database if not already open.
331 	     */
332 	    if (fd >= 0) {
333 		(void) lseek(fd, (off_t) 0, SEEK_SET);
334 	    } else if ((_nc_access(db_array[current], R_OK) < 0)
335 		       || (fd = open(db_array[current], O_RDONLY, 0)) < 0) {
336 		/* No error on unfound file. */
337 		if (errno == ENOENT)
338 		    continue;
339 		free(record);
340 		return (TC_SYS_ERR);
341 	    } else {
342 		myfd = TRUE;
343 	    }
344 	    lineno = 0;
345 
346 	    /*
347 	     * Find the requested capability record ...
348 	     */
349 	    {
350 		char buf[2048];
351 		register char *b_end = buf;
352 		register char *bp = buf;
353 		register int c;
354 
355 		/*
356 		 * Loop invariants:
357 		 *      There is always room for one more character in record.
358 		 *      R_end always points just past end of record.
359 		 *      Rp always points just past last character in record.
360 		 *      B_end always points just past last character in buf.
361 		 *      Bp always points at next character in buf.
362 		 */
363 
364 		for (;;) {
365 		    int first = lineno + 1;
366 
367 		    /*
368 		     * Read in a line implementing (\, newline)
369 		     * line continuation.
370 		     */
371 		    rp = record;
372 		    for (;;) {
373 			if (bp >= b_end) {
374 			    int n;
375 
376 			    n = read(fd, buf, sizeof(buf));
377 			    if (n <= 0) {
378 				if (myfd)
379 				    (void) close(fd);
380 				if (n < 0) {
381 				    free(record);
382 				    return (TC_SYS_ERR);
383 				}
384 				fd = -1;
385 				eof = TRUE;
386 				break;
387 			    }
388 			    b_end = buf + n;
389 			    bp = buf;
390 			}
391 
392 			c = *bp++;
393 			if (c == '\n') {
394 			    lineno++;
395 			    if (rp == record || *(rp - 1) != '\\')
396 				break;
397 			}
398 			*rp++ = c;
399 
400 			/*
401 			 * Enforce loop invariant: if no room
402 			 * left in record buffer, try to get
403 			 * some more.
404 			 */
405 			if (rp >= r_end) {
406 			    unsigned pos;
407 			    size_t newsize;
408 
409 			    pos = rp - record;
410 			    newsize = r_end - record + BFRAG;
411 			    record = DOALLOC(newsize);
412 			    if (record == 0) {
413 				if (myfd)
414 				    (void) close(fd);
415 				errno = ENOMEM;
416 				return (TC_SYS_ERR);
417 			    }
418 			    r_end = record + newsize;
419 			    rp = record + pos;
420 			}
421 		    }
422 		    /* loop invariant lets us do this */
423 		    *rp++ = '\0';
424 
425 		    /*
426 		     * If encountered eof check next file.
427 		     */
428 		    if (eof)
429 			break;
430 
431 		    /*
432 		     * Toss blank lines and comments.
433 		     */
434 		    if (*record == '\0' || *record == '#')
435 			continue;
436 
437 		    /*
438 		     * See if this is the record we want ...
439 		     */
440 		    if (_nc_cgetmatch(record, name) == 0
441 			&& (nfield == 0
442 			    || !_nc_nfcmp(nfield, record))) {
443 			foundit = TRUE;
444 			*beginning = first;
445 			break;	/* found it! */
446 		    }
447 		}
448 	    }
449 	    if (foundit)
450 		break;
451 	}
452 
453 	if (!foundit)
454 	    return (TC_NOT_FOUND);
455     }
456 
457     /*
458      * Got the capability record, but now we have to expand all tc=name
459      * references in it ...
460      */
461     {
462 	register char *newicap, *s;
463 	register int newilen;
464 	unsigned ilen;
465 	int diff, iret, tclen, oline;
466 	char *icap, *scan, *tc, *tcstart, *tcend;
467 
468 	/*
469 	 * Loop invariants:
470 	 *      There is room for one more character in record.
471 	 *      R_end points just past end of record.
472 	 *      Rp points just past last character in record.
473 	 *      Scan points at remainder of record that needs to be
474 	 *      scanned for tc=name constructs.
475 	 */
476 	scan = record;
477 	tc_not_resolved = FALSE;
478 	for (;;) {
479 	    if ((tc = _nc_cgetcap(scan, "tc", '=')) == 0)
480 		break;
481 
482 	    /*
483 	     * Find end of tc=name and stomp on the trailing `:'
484 	     * (if present) so we can use it to call ourselves.
485 	     */
486 	    s = tc;
487 	    while (*s != '\0') {
488 		if (*s++ == ':') {
489 		    *(s - 1) = '\0';
490 		    break;
491 		}
492 	    }
493 	    tcstart = tc - 3;
494 	    tclen = s - tcstart;
495 	    tcend = s;
496 
497 	    iret = _nc_getent(&icap, &ilen, &oline, current, db_array, fd,
498 			      tc, depth + 1, 0);
499 	    newicap = icap;	/* Put into a register. */
500 	    newilen = ilen;
501 	    if (iret != TC_SUCCESS) {
502 		/* an error */
503 		if (iret < TC_NOT_FOUND) {
504 		    if (myfd)
505 			(void) close(fd);
506 		    free(record);
507 		    return (iret);
508 		}
509 		if (iret == TC_UNRESOLVED)
510 		    tc_not_resolved = TRUE;
511 		/* couldn't resolve tc */
512 		if (iret == TC_NOT_FOUND) {
513 		    *(s - 1) = ':';
514 		    scan = s - 1;
515 		    tc_not_resolved = TRUE;
516 		    continue;
517 		}
518 	    }
519 
520 	    /* not interested in name field of tc'ed record */
521 	    s = newicap;
522 	    while (*s != '\0' && *s++ != ':') ;
523 	    newilen -= s - newicap;
524 	    newicap = s;
525 
526 	    /* make sure interpolated record is `:'-terminated */
527 	    s += newilen;
528 	    if (*(s - 1) != ':') {
529 		*s = ':';	/* overwrite NUL with : */
530 		newilen++;
531 	    }
532 
533 	    /*
534 	     * Make sure there's enough room to insert the
535 	     * new record.
536 	     */
537 	    diff = newilen - tclen;
538 	    if (diff >= r_end - rp) {
539 		unsigned pos, tcpos, tcposend;
540 		size_t newsize;
541 
542 		pos = rp - record;
543 		newsize = r_end - record + diff + BFRAG;
544 		tcpos = tcstart - record;
545 		tcposend = tcend - record;
546 		record = DOALLOC(newsize);
547 		if (record == 0) {
548 		    if (myfd)
549 			(void) close(fd);
550 		    free(icap);
551 		    errno = ENOMEM;
552 		    return (TC_SYS_ERR);
553 		}
554 		r_end = record + newsize;
555 		rp = record + pos;
556 		tcstart = record + tcpos;
557 		tcend = record + tcposend;
558 	    }
559 
560 	    /*
561 	     * Insert tc'ed record into our record.
562 	     */
563 	    s = tcstart + newilen;
564 	    memmove(s, tcend, (size_t) (rp - tcend));
565 	    memmove(tcstart, newicap, (size_t) newilen);
566 	    rp += diff;
567 	    free(icap);
568 
569 	    /*
570 	     * Start scan on `:' so next cgetcap works properly
571 	     * (cgetcap always skips first field).
572 	     */
573 	    scan = s - 1;
574 	}
575     }
576 
577     /*
578      * Close file (if we opened it), give back any extra memory, and
579      * return capability, length and success.
580      */
581     if (myfd)
582 	(void) close(fd);
583     *len = rp - record - 1;	/* don't count NUL */
584     if (r_end > rp) {
585 	if ((record = DOALLOC((size_t) (rp - record))) == 0) {
586 	    errno = ENOMEM;
587 	    return (TC_SYS_ERR);
588 	}
589     }
590 
591     *cap = record;
592     if (tc_not_resolved)
593 	return (TC_UNRESOLVED);
594     return (current);
595 }
596 
597 /*
598  * Cgetmatch will return 0 if name is one of the names of the capability
599  * record buf, -1 if not.
600  */
601 static int
_nc_cgetmatch(char * buf,const char * name)602 _nc_cgetmatch(char *buf, const char *name)
603 {
604     register const char *np;
605     register char *bp;
606 
607     /*
608      * Start search at beginning of record.
609      */
610     bp = buf;
611     for (;;) {
612 	/*
613 	 * Try to match a record name.
614 	 */
615 	np = name;
616 	for (;;) {
617 	    if (*np == '\0') {
618 		if (*bp == '|' || *bp == ':' || *bp == '\0')
619 		    return (0);
620 		else
621 		    break;
622 	    } else if (*bp++ != *np++) {
623 		break;
624 	    }
625 	}
626 
627 	/*
628 	 * Match failed, skip to next name in record.
629 	 */
630 	bp--;			/* a '|' or ':' may have stopped the match */
631 	for (;;) {
632 	    if (*bp == '\0' || *bp == ':')
633 		return (-1);	/* match failed totally */
634 	    else if (*bp++ == '|')
635 		break;		/* found next name */
636 	}
637     }
638 }
639 
640 /*
641  * Compare name field of record.
642  */
643 static int
_nc_nfcmp(const char * nf,char * rec)644 _nc_nfcmp(const char *nf, char *rec)
645 {
646     char *cp, tmp;
647     int ret;
648 
649     for (cp = rec; *cp != ':'; cp++) ;
650 
651     tmp = *(cp + 1);
652     *(cp + 1) = '\0';
653     ret = strcmp(nf, rec);
654     *(cp + 1) = tmp;
655 
656     return (ret);
657 }
658 #endif /* HAVE_BSD_CGETENT */
659 
660 /*
661  * Since ncurses provides its own 'tgetent()', we cannot use the native one.
662  * So we reproduce the logic to get down to cgetent() -- or our cut-down
663  * version of that -- to circumvent the problem of configuring against the
664  * termcap library.
665  */
666 #define USE_BSD_TGETENT 1
667 
668 #if USE_BSD_TGETENT
669 /*
670  * Copyright (c) 1980, 1993
671  *	The Regents of the University of California.  All rights reserved.
672  *
673  * Redistribution and use in source and binary forms, with or without
674  * modification, are permitted provided that the following conditions
675  * are met:
676  * 1. Redistributions of source code must retain the above copyright
677  *    notice, this list of conditions and the following disclaimer.
678  * 2. Redistributions in binary form must reproduce the above copyright
679  *    notice, this list of conditions and the following disclaimer in the
680  *    documentation and/or other materials provided with the distribution.
681  * 3. All advertising materials mentioning features or use of this software
682  *    must display the following acknowledgment:
683  *	This product includes software developed by the University of
684  *	California, Berkeley and its contributors.
685  * 4. Neither the name of the University nor the names of its contributors
686  *    may be used to endorse or promote products derived from this software
687  *    without specific prior written permission.
688  *
689  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
690  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
691  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
692  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
693  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
694  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
695  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
696  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
697  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
698  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
699  * SUCH DAMAGE.
700  */
701 
702 /* static char sccsid[] = "@(#)termcap.c	8.1 (Berkeley) 6/4/93" */
703 
704 #define	PBUFSIZ		512	/* max length of filename path */
705 #define	PVECSIZ		32	/* max number of names in path */
706 #define TBUFSIZ (2048*2)
707 
708 static char *tbuf;
709 
710 /*
711  * On entry, srcp points to a non ':' character which is the beginning of the
712  * token, if any.  We'll try to return a string that doesn't end with a ':'.
713  */
714 static char *
get_tc_token(char ** srcp,int * endp)715 get_tc_token(char **srcp, int *endp)
716 {
717     int ch;
718     bool found = FALSE;
719     char *s, *base;
720     char *tok = 0;
721 
722     *endp = TRUE;
723     for (s = base = *srcp; *s != '\0';) {
724 	ch = *s++;
725 	if (ch == '\\') {
726 	    if (*s == '\0') {
727 		break;
728 	    } else if (*s++ == '\n') {
729 		while (isspace(UChar(*s)))
730 		    s++;
731 	    } else {
732 		found = TRUE;
733 	    }
734 	} else if (ch == ':') {
735 	    if (found) {
736 		tok = base;
737 		s[-1] = '\0';
738 		*srcp = s;
739 		*endp = FALSE;
740 		break;
741 	    }
742 	    base = s;
743 	} else if (isgraph(UChar(ch))) {
744 	    found = TRUE;
745 	}
746     }
747 
748     /* malformed entry may end without a ':' */
749     if (tok == 0 && found) {
750 	tok = base;
751     }
752 
753     return tok;
754 }
755 
756 static char *
copy_tc_token(char * dst,const char * src,size_t len)757 copy_tc_token(char *dst, const char *src, size_t len)
758 {
759     int ch;
760 
761     while ((ch = *src++) != '\0') {
762 	if (ch == '\\' && *src == '\n') {
763 	    while (isspace(UChar(*src)))
764 		src++;
765 	    continue;
766 	}
767 	if (--len == 0) {
768 	    dst = 0;
769 	    break;
770 	}
771 	*dst++ = ch;
772     }
773     return dst;
774 }
775 
776 /*
777  * Get an entry for terminal name in buffer bp from the termcap file.
778  */
779 static int
_nc_tgetent(char * bp,char ** sourcename,int * lineno,const char * name)780 _nc_tgetent(char *bp, char **sourcename, int *lineno __attribute__((__unused__)),
781     const char *name)
782 {
783     static char *the_source;
784 
785     register char *p;
786     register char *cp;
787     char *dummy = NULL;
788     char **fname;
789     char *home;
790     int i;
791     char pathbuf[PBUFSIZ];	/* holds raw path of filenames */
792     char *pathvec[PVECSIZ];	/* to point to names in pathbuf */
793     char **pvec;		/* holds usable tail of path vector */
794     NCURSES_CONST char *termpath;
795     string_desc desc;
796 
797     fname = pathvec;
798     pvec = pathvec;
799     tbuf = bp;
800     p = pathbuf;
801     cp = use_terminfo_vars()? getenv("TERMCAP") : NULL;
802 
803     /*
804      * TERMCAP can have one of two things in it.  It can be the name of a file
805      * to use instead of /etc/termcap.  In this case it better start with a
806      * "/".  Or it can be an entry to use so we don't have to read the file.
807      * In this case it has to already have the newlines crunched out.  If
808      * TERMCAP does not hold a file name then a path of names is searched
809      * instead.  The path is found in the TERMPATH variable, or becomes
810      * "$HOME/.termcap /etc/termcap" if no TERMPATH exists.
811      */
812     _nc_str_init(&desc, pathbuf, sizeof(pathbuf));
813     if (cp == NULL) {
814 	_nc_safe_strcpy(&desc, get_termpath());
815     } else if (!is_pathname(cp)) {	/* TERMCAP holds an entry */
816 	if ((termpath = get_termpath()) != 0) {
817 	    _nc_safe_strcat(&desc, termpath);
818 	} else {
819 	    char temp[PBUFSIZ];
820 	    temp[0] = 0;
821 	    if ((home = getenv("HOME")) != 0 && *home != '\0'
822 		&& strchr(home, ' ') == 0
823 		&& strlen(home) < sizeof(temp) - 10) {	/* setup path */
824 		sprintf(temp, "%s/", home);	/* $HOME first */
825 	    }
826 	    /* if no $HOME look in current directory */
827 	    strcat(temp, ".termcap");
828 	    _nc_safe_strcat(&desc, temp);
829 	    _nc_safe_strcat(&desc, " ");
830 	    _nc_safe_strcat(&desc, get_termpath());
831 	}
832     } else {			/* user-defined name in TERMCAP */
833 	_nc_safe_strcat(&desc, cp);	/* still can be tokenized */
834     }
835 
836     *fname++ = pathbuf;		/* tokenize path into vector of names */
837     while (*++p) {
838 	if (*p == ' ' || *p == NCURSES_PATHSEP) {
839 	    *p = '\0';
840 	    while (*++p)
841 		if (*p != ' ' && *p != NCURSES_PATHSEP)
842 		    break;
843 	    if (*p == '\0')
844 		break;
845 	    *fname++ = p;
846 	    if (fname >= pathvec + PVECSIZ) {
847 		fname--;
848 		break;
849 	    }
850 	}
851     }
852     *fname = 0;			/* mark end of vector */
853     if (is_pathname(cp)) {
854 	if (_nc_cgetset(cp) < 0) {
855 	    return (TC_SYS_ERR);
856 	}
857     }
858 
859     i = _nc_cgetent(&dummy, lineno, pathvec, name);
860 
861     /* ncurses' termcap-parsing routines cannot handle multiple adjacent
862      * empty fields, and mistakenly use the last valid cap entry instead of
863      * the first (breaks tc= includes)
864      */
865     if (i >= 0) {
866 	char *pd, *ps, *tok;
867 	int endflag = FALSE;
868 	char *list[1023];
869 	size_t n, count = 0;
870 
871 	pd = bp;
872 	ps = dummy;
873 	while (!endflag && (tok = get_tc_token(&ps, &endflag)) != 0) {
874 	    bool ignore = FALSE;
875 
876 	    for (n = 1; n < count; n++) {
877 		char *s = list[n];
878 		if (s[0] == tok[0]
879 		    && s[1] == tok[1]) {
880 		    ignore = TRUE;
881 		    break;
882 		}
883 	    }
884 	    if (ignore != TRUE) {
885 		list[count++] = tok;
886 		pd = copy_tc_token(pd, tok, TBUFSIZ - (2 + pd - bp));
887 		if (pd == 0) {
888 		    i = -1;
889 		    break;
890 		}
891 		*pd++ = ':';
892 		*pd = '\0';
893 	    }
894 	}
895     }
896 
897     FreeIfNeeded(dummy);
898     FreeIfNeeded(the_source);
899     the_source = 0;
900 
901     /* This is not related to the BSD cgetent(), but to fake up a suitable
902      * filename for ncurses' error reporting.  (If we are not using BSD
903      * cgetent, then it is the actual filename).
904      */
905     if (i >= 0) {
906 	if ((the_source = strdup(pathvec[i])) != 0)
907 	    *sourcename = the_source;
908     }
909 
910     return (i);
911 }
912 #endif /* USE_BSD_TGETENT */
913 #endif /* USE_GETCAP */
914 
915 #define MAXPATHS	32
916 
917 /*
918  * Add a filename to the list in 'termpaths[]', checking that we really have
919  * a right to open the file.
920  */
921 #if !USE_GETCAP
922 static int
add_tc(char * termpaths[],char * path,int count)923 add_tc(char *termpaths[], char *path, int count)
924 {
925     char *save = strchr(path, NCURSES_PATHSEP);
926     if (save != 0)
927 	*save = '\0';
928     if (count < MAXPATHS
929 	&& _nc_access(path, R_OK) == 0) {
930 	termpaths[count++] = path;
931 	T(("Adding termpath %s", path));
932     }
933     termpaths[count] = 0;
934     if (save != 0)
935 	*save = NCURSES_PATHSEP;
936     return count;
937 }
938 #define ADD_TC(path, count) filecount = add_tc(termpaths, path, count)
939 #endif /* !USE_GETCAP */
940 
941 NCURSES_EXPORT(int)
_nc_read_termcap_entry(const char * const tn,TERMTYPE * const tp)942 _nc_read_termcap_entry(const char *const tn, TERMTYPE *const tp)
943 {
944     int found = FALSE;
945     ENTRY *ep;
946 #if USE_GETCAP_CACHE
947     char cwd_buf[PATH_MAX];
948 #endif
949 #if USE_GETCAP
950     char *p, tc[TBUFSIZ];
951     static char *source;
952     static int lineno;
953 
954     T(("read termcap entry for %s", tn));
955 
956     if (strlen(tn) == 0
957 	|| strcmp(tn, ".") == 0
958 	|| strcmp(tn, "..") == 0
959 	|| _nc_pathlast(tn) != 0) {
960 	T(("illegal or missing entry name '%s'", tn));
961 	return 0;
962     }
963 
964     if (use_terminfo_vars() && (p = getenv("TERMCAP")) != 0
965 	&& !is_pathname(p) && _nc_name_match(p, tn, "|:")) {
966 	/* TERMCAP holds a termcap entry */
967 	strncpy(tc, p, sizeof(tc) - 1);
968 	tc[sizeof(tc) - 1] = '\0';
969 	_nc_set_source("TERMCAP");
970     } else {
971 	/* we're using getcap(3) */
972 	if (_nc_tgetent(tc, &source, &lineno, tn) < 0)
973 	    return (ERR);
974 
975 	_nc_curr_line = lineno;
976 	_nc_set_source(source);
977     }
978     _nc_read_entry_source((FILE *) 0, tc, FALSE, FALSE, NULLHOOK);
979 #else
980     /*
981      * Here is what the 4.4BSD termcap(3) page prescribes:
982      *
983      * It will look in the environment for a TERMCAP variable.  If found, and
984      * the value does not begin with a slash, and the terminal type name is the
985      * same as the environment string TERM, the TERMCAP string is used instead
986      * of reading a termcap file.  If it does begin with a slash, the string is
987      * used as a path name of the termcap file to search.  If TERMCAP does not
988      * begin with a slash and name is different from TERM, tgetent() searches
989      * the files $HOME/.termcap and /usr/share/misc/termcap, in that order,
990      * unless the environment variable TERMPATH exists, in which case it
991      * specifies a list of file pathnames (separated by spaces or colons) to be
992      * searched instead.
993      *
994      * It goes on to state:
995      *
996      * Whenever multiple files are searched and a tc field occurs in the
997      * requested entry, the entry it names must be found in the same file or
998      * one of the succeeding files.
999      *
1000      * However, this restriction is relaxed in ncurses; tc references to
1001      * previous files are permitted.
1002      *
1003      * This routine returns 1 if an entry is found, 0 if not found, and -1 if
1004      * the database is not accessible.
1005      */
1006     FILE *fp;
1007     char *tc, *termpaths[MAXPATHS];
1008     int filecount = 0;
1009     int j, k;
1010     bool use_buffer = FALSE;
1011     bool normal = TRUE;
1012     char tc_buf[1024];
1013     char pathbuf[PATH_MAX];
1014     char *copied = 0;
1015     char *cp;
1016     struct stat test_stat[MAXPATHS];
1017 
1018     termpaths[filecount] = 0;
1019     if (use_terminfo_vars() && (tc = getenv("TERMCAP")) != 0) {
1020 	if (is_pathname(tc)) {	/* interpret as a filename */
1021 	    ADD_TC(tc, 0);
1022 	    normal = FALSE;
1023 	} else if (_nc_name_match(tc, tn, "|:")) {	/* treat as a capability file */
1024 	    use_buffer = TRUE;
1025 	    (void) sprintf(tc_buf, "%.*s\n", (int) sizeof(tc_buf) - 2, tc);
1026 	    normal = FALSE;
1027 	}
1028     }
1029 
1030     if (normal) {		/* normal case */
1031 	char envhome[PATH_MAX], *h;
1032 
1033 	copied = strdup(get_termpath());
1034 	for (cp = copied; *cp; cp++) {
1035 	    if (*cp == NCURSES_PATHSEP)
1036 		*cp = '\0';
1037 	    else if (cp == copied || cp[-1] == '\0') {
1038 		ADD_TC(cp, filecount);
1039 	    }
1040 	}
1041 
1042 #define PRIVATE_CAP "%s/.termcap"
1043 
1044 	if (use_terminfo_vars() && (h = getenv("HOME")) != NULL && *h != '\0'
1045 	    && (strlen(h) + sizeof(PRIVATE_CAP)) < PATH_MAX) {
1046 	    /* user's .termcap, if any, should override it */
1047 	    (void) strcpy(envhome, h);
1048 	    (void) sprintf(pathbuf, PRIVATE_CAP, envhome);
1049 	    ADD_TC(pathbuf, filecount);
1050 	}
1051     }
1052 
1053     /*
1054      * Probably /etc/termcap is a symlink to /usr/share/misc/termcap.
1055      * Avoid reading the same file twice.
1056      */
1057 #if HAVE_LINK
1058     for (j = 0; j < filecount; j++) {
1059 	bool omit = FALSE;
1060 	if (stat(termpaths[j], &test_stat[j]) != 0
1061 	    || (test_stat[j].st_mode & S_IFMT) != S_IFREG) {
1062 	    omit = TRUE;
1063 	} else {
1064 	    for (k = 0; k < j; k++) {
1065 		if (test_stat[k].st_dev == test_stat[j].st_dev
1066 		    && test_stat[k].st_ino == test_stat[j].st_ino) {
1067 		    omit = TRUE;
1068 		    break;
1069 		}
1070 	    }
1071 	}
1072 	if (omit) {
1073 	    T(("Path %s is a duplicate", termpaths[j]));
1074 	    for (k = j + 1; k < filecount; k++) {
1075 		termpaths[k - 1] = termpaths[k];
1076 		test_stat[k - 1] = test_stat[k];
1077 	    }
1078 	    --filecount;
1079 	    --j;
1080 	}
1081     }
1082 #endif
1083 
1084     /* parse the sources */
1085     if (use_buffer) {
1086 	_nc_set_source("TERMCAP");
1087 
1088 	/*
1089 	 * We don't suppress warning messages here.  The presumption is
1090 	 * that since it's just a single entry, they won't be a pain.
1091 	 */
1092 	_nc_read_entry_source((FILE *) 0, tc_buf, FALSE, FALSE, NULLHOOK);
1093     } else {
1094 	int i;
1095 
1096 	for (i = 0; i < filecount; i++) {
1097 
1098 	    T(("Looking for %s in %s", tn, termpaths[i]));
1099 	    if (_nc_access(termpaths[i], R_OK) == 0
1100 		&& (fp = fopen(termpaths[i], "r")) != (FILE *) 0) {
1101 		_nc_set_source(termpaths[i]);
1102 
1103 		/*
1104 		 * Suppress warning messages.  Otherwise you get 400 lines of
1105 		 * crap from archaic termcap files as ncurses complains about
1106 		 * all the obsolete capabilities.
1107 		 */
1108 		_nc_read_entry_source(fp, (char *) 0, FALSE, TRUE, NULLHOOK);
1109 
1110 		(void) fclose(fp);
1111 	    }
1112 	}
1113     }
1114     if (copied != 0)
1115 	free(copied);
1116 #endif /* USE_GETCAP */
1117 
1118     if (_nc_head == 0)
1119 	return (ERR);
1120 
1121     /* resolve all use references */
1122     _nc_resolve_uses2(TRUE, FALSE);
1123 
1124     /* find a terminal matching tn, if we can */
1125 #if USE_GETCAP_CACHE
1126     if (getcwd(cwd_buf, sizeof(cwd_buf)) != 0) {
1127 	_nc_set_writedir((char *) 0);	/* note: this does a chdir */
1128 #endif
1129 	for_entry_list(ep) {
1130 	    if (_nc_name_match(ep->tterm.term_names, tn, "|:")) {
1131 		/*
1132 		 * Make a local copy of the terminal capabilities, delinked
1133 		 * from the list.
1134 		 */
1135 		*tp = ep->tterm;
1136 		_nc_delink_entry(_nc_head, &(ep->tterm));
1137 		free(ep);
1138 
1139 		/*
1140 		 * OK, now try to write the type to user's terminfo directory.
1141 		 * Next time he loads this, it will come through terminfo.
1142 		 *
1143 		 * Advantage:  Second and subsequent fetches of this entry will
1144 		 * be very fast.
1145 		 *
1146 		 * Disadvantage:  After the first time a termcap type is loaded
1147 		 * by its user, editing it in the /etc/termcap file, or in
1148 		 * TERMCAP, or in a local ~/.termcap, will be ineffective
1149 		 * unless the terminfo entry is explicitly removed.
1150 		 */
1151 #if USE_GETCAP_CACHE
1152 		(void) _nc_write_entry(tp);
1153 #endif
1154 		found = TRUE;
1155 		break;
1156 	    }
1157 	}
1158 #if USE_GETCAP_CACHE
1159 	chdir(cwd_buf);
1160     }
1161 #endif
1162 
1163     return (found);
1164 }
1165 #else
1166 extern
1167 NCURSES_EXPORT(void)
1168 _nc_read_termcap(void);
1169 NCURSES_EXPORT(void)
_nc_read_termcap(void)1170 _nc_read_termcap(void)
1171 {
1172 }
1173 #endif /* PURE_TERMINFO */
1174