1 /****************************************************************************
2  * Copyright 2018,2020 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  *     and: Juergen Pfeifer                                                 *
35  *                                                                          *
36  * some of the code in here was contributed by:                             *
37  * Magnus Bengtsson, d6mbeng@dtek.chalmers.se (Nov'93)                      *
38  * (but it has changed a lot)                                               *
39  ****************************************************************************/
40 
41 /* $FreeBSD$ */
42 
43 #define __INTERNAL_CAPS_VISIBLE
44 #include <curses.priv.h>
45 
46 #include <termcap.h>
47 #include <tic.h>
48 #include <ctype.h>
49 
50 #ifndef CUR
51 #define CUR SP_TERMTYPE
52 #endif
53 
54 MODULE_ID("$Id: lib_termcap.c,v 1.88 2020/02/02 23:34:34 tom Exp $")
55 
56 NCURSES_EXPORT_VAR(char *) UP = 0;
57 NCURSES_EXPORT_VAR(char *) BC = 0;
58 
59 #ifdef FREEBSD_NATIVE
60 extern char _nc_termcap[];	/* buffer to copy out */
61 #endif
62 
63 #define MyCache  _nc_globals.tgetent_cache
64 #define CacheInx _nc_globals.tgetent_index
65 #define CacheSeq _nc_globals.tgetent_sequence
66 
67 #define FIX_SGR0 MyCache[CacheInx].fix_sgr0
68 #define LAST_TRM MyCache[CacheInx].last_term
69 #define LAST_BUF MyCache[CacheInx].last_bufp
70 #define LAST_USE MyCache[CacheInx].last_used
71 #define LAST_SEQ MyCache[CacheInx].sequence
72 
73 /*
74  * Termcap names are matched only using the first two bytes.
75  * Ignore any extended names longer than two bytes, to avoid problems
76  * with legacy code which passes in parameters whose use is long forgotten.
77  */
78 #define ValidCap(cap) (((cap)[0] != '\0') && ((cap)[1] != '\0'))
79 #define SameCap(a,b)  (((a)[0] == (b)[0]) && ((a)[1] == (b)[1]))
80 #define ValidExt(ext) (ValidCap(ext) && (ext)[2] == '\0')
81 
82 /***************************************************************************
83  *
84  * tgetent(bufp, term)
85  *
86  * In termcap, this function reads in the entry for terminal `term' into the
87  * buffer pointed to by bufp. It must be called before any of the functions
88  * below are called.
89  * In this terminfo emulation, tgetent() simply calls setupterm() (which
90  * does a bit more than tgetent() in termcap does), and returns its return
91  * value (1 if successful, 0 if no terminal with the given name could be
92  * found, or -1 if no terminal descriptions have been installed on the
93  * system).  The bufp argument is ignored.
94  *
95  ***************************************************************************/
96 
97 NCURSES_EXPORT(int)
98 NCURSES_SP_NAME(tgetent) (NCURSES_SP_DCLx char *bufp, const char *name)
99 {
100     int rc = ERR;
101     int n;
102     bool found_cache = FALSE;
103 #ifdef USE_TERM_DRIVER
104     TERMINAL *termp = 0;
105 #endif
106 
107     START_TRACE();
108     T((T_CALLED("tgetent()")));
109 
110     TINFO_SETUP_TERM(&termp, name, STDOUT_FILENO, &rc, TRUE);
111 
112 #ifdef USE_TERM_DRIVER
113     if (termp == 0 ||
114 	!((TERMINAL_CONTROL_BLOCK *) termp)->drv->isTerminfo)
115 	returnCode(rc);
116 #endif
117 
118     /*
119      * In general we cannot tell if the fixed sgr0 is still used by the
120      * caller, but if tgetent() is called with the same buffer, that is
121      * good enough, since the previous data would be invalidated by the
122      * current call.
123      *
124      * bufp may be a null pointer, e.g., GNU termcap.  That allocates data,
125      * which is good until the next tgetent() call.  The conventional termcap
126      * is inconvenient because of the fixed buffer size, but because it uses
127      * caller-supplied buffers, can have multiple terminal descriptions in
128      * use at a given time.
129      */
130     for (n = 0; n < TGETENT_MAX; ++n) {
131 	bool same_result = (MyCache[n].last_used && MyCache[n].last_bufp == bufp);
132 	if (same_result) {
133 	    CacheInx = n;
134 	    if (FIX_SGR0 != 0) {
135 		FreeAndNull(FIX_SGR0);
136 	    }
137 	    /*
138 	     * Also free the terminfo data that we loaded (much bigger leak).
139 	     */
140 	    if (LAST_TRM != 0 && LAST_TRM != TerminalOf(SP_PARM)) {
141 		TERMINAL *trm = LAST_TRM;
142 		NCURSES_SP_NAME(del_curterm) (NCURSES_SP_ARGx LAST_TRM);
143 		for (CacheInx = 0; CacheInx < TGETENT_MAX; ++CacheInx)
144 		    if (LAST_TRM == trm)
145 			LAST_TRM = 0;
146 		CacheInx = n;
147 	    }
148 	    found_cache = TRUE;
149 	    break;
150 	}
151     }
152     if (!found_cache) {
153 	int best = 0;
154 
155 	for (CacheInx = 0; CacheInx < TGETENT_MAX; ++CacheInx) {
156 	    if (LAST_SEQ < MyCache[best].sequence) {
157 		best = CacheInx;
158 	    }
159 	}
160 	CacheInx = best;
161     }
162     if (rc == 1) {
163 	LAST_TRM = TerminalOf(SP_PARM);
164 	LAST_SEQ = ++CacheSeq;
165     } else {
166 	LAST_TRM = 0;
167     }
168 
169     PC = 0;
170     UP = 0;
171     BC = 0;
172     FIX_SGR0 = 0;		/* don't free it - application may still use */
173 
174     if (rc == 1) {
175 
176 	if (cursor_left)
177 	    if ((backspaces_with_bs = (char) !strcmp(cursor_left, "\b")) == 0)
178 		backspace_if_not_bs = cursor_left;
179 
180 	/* we're required to export these */
181 	if (pad_char != NULL)
182 	    PC = pad_char[0];
183 	if (cursor_up != NULL)
184 	    UP = cursor_up;
185 	if (backspace_if_not_bs != NULL)
186 	    BC = backspace_if_not_bs;
187 
188 	if ((FIX_SGR0 = _nc_trim_sgr0(&TerminalType(TerminalOf(SP_PARM))))
189 	    != 0) {
190 	    if (!strcmp(FIX_SGR0, exit_attribute_mode)) {
191 		if (FIX_SGR0 != exit_attribute_mode) {
192 		    free(FIX_SGR0);
193 		}
194 		FIX_SGR0 = 0;
195 	    }
196 	}
197 	LAST_BUF = bufp;
198 	LAST_USE = TRUE;
199 
200 	SetNoPadding(SP_PARM);
201 	(void) NCURSES_SP_NAME(baudrate) (NCURSES_SP_ARG);	/* sets ospeed as a side-effect */
202 
203 /* LINT_PREPRO
204 #if 0*/
205 #include <capdefaults.c>
206 /* LINT_PREPRO
207 #endif*/
208 
209     }
210 
211 #ifdef FREEBSD_NATIVE
212     /*
213      * This is a REALLY UGLY hack. Basically, if we originate with
214      * a termcap source, try and copy it out.
215      */
216     if (bufp && _nc_termcap[0])
217 	strncpy(bufp, _nc_termcap, 1024);
218 #endif
219 
220     returnCode(rc);
221 }
222 
223 #if NCURSES_SP_FUNCS
224 NCURSES_EXPORT(int)
225 tgetent(char *bufp, const char *name)
226 {
227     return NCURSES_SP_NAME(tgetent) (CURRENT_SCREEN, bufp, name);
228 }
229 #endif
230 
231 #if 0
232 static bool
233 same_tcname(const char *a, const char *b)
234 {
235     bool code = SameCap(a, b);
236     fprintf(stderr, "compare(%s,%s) %s\n", a, b, code ? "same" : "diff");
237     return code;
238 }
239 
240 #else
241 #define same_tcname(a,b) SameCap(a,b)
242 #endif
243 
244 /***************************************************************************
245  *
246  * tgetflag(str)
247  *
248  * Look up boolean termcap capability str and return its value (TRUE=1 if
249  * present, FALSE=0 if not).
250  *
251  ***************************************************************************/
252 
253 NCURSES_EXPORT(int)
254 NCURSES_SP_NAME(tgetflag) (NCURSES_SP_DCLx const char *id)
255 {
256     int result = 0;		/* Solaris returns zero for missing flag */
257 
258     T((T_CALLED("tgetflag(%p, %s)"), (void *) SP_PARM, id));
259     if (HasTInfoTerminal(SP_PARM) && ValidCap(id)) {
260 	TERMTYPE2 *tp = &TerminalType(TerminalOf(SP_PARM));
261 	struct name_table_entry const *entry_ptr;
262 	int j = -1;
263 
264 	entry_ptr = _nc_find_type_entry(id, BOOLEAN, TRUE);
265 	if (entry_ptr != 0) {
266 	    j = entry_ptr->nte_index;
267 	}
268 #if NCURSES_XNAMES
269 	else {
270 	    int i;
271 	    for_each_ext_boolean(i, tp) {
272 		const char *capname = ExtBoolname(tp, i, boolcodes);
273 		if (same_tcname(id, capname) && ValidExt(capname)) {
274 		    j = i;
275 		    break;
276 		}
277 	    }
278 	}
279 #endif
280 	if (j >= 0) {
281 	    /* note: setupterm forces invalid booleans to false */
282 	    result = tp->Booleans[j];
283 	}
284     }
285     returnCode(result);
286 }
287 
288 #if NCURSES_SP_FUNCS
289 NCURSES_EXPORT(int)
290 tgetflag(const char *id)
291 {
292     return NCURSES_SP_NAME(tgetflag) (CURRENT_SCREEN, id);
293 }
294 #endif
295 
296 /***************************************************************************
297  *
298  * tgetnum(str)
299  *
300  * Look up numeric termcap capability str and return its value, or -1 if
301  * not given.
302  *
303  ***************************************************************************/
304 
305 NCURSES_EXPORT(int)
306 NCURSES_SP_NAME(tgetnum) (NCURSES_SP_DCLx const char *id)
307 {
308     int result = ABSENT_NUMERIC;
309 
310     T((T_CALLED("tgetnum(%p, %s)"), (void *) SP_PARM, id));
311     if (HasTInfoTerminal(SP_PARM) && ValidCap(id)) {
312 	TERMTYPE2 *tp = &TerminalType(TerminalOf(SP_PARM));
313 	struct name_table_entry const *entry_ptr;
314 	int j = -1;
315 
316 	entry_ptr = _nc_find_type_entry(id, NUMBER, TRUE);
317 	if (entry_ptr != 0) {
318 	    j = entry_ptr->nte_index;
319 	}
320 #if NCURSES_XNAMES
321 	else {
322 	    int i;
323 	    for_each_ext_number(i, tp) {
324 		const char *capname = ExtNumname(tp, i, numcodes);
325 		if (same_tcname(id, capname) && ValidExt(capname)) {
326 		    j = i;
327 		    break;
328 		}
329 	    }
330 	}
331 #endif
332 	if (j >= 0) {
333 	    if (VALID_NUMERIC(tp->Numbers[j]))
334 		result = tp->Numbers[j];
335 	}
336     }
337     returnCode(result);
338 }
339 
340 #if NCURSES_SP_FUNCS
341 NCURSES_EXPORT(int)
342 tgetnum(const char *id)
343 {
344     return NCURSES_SP_NAME(tgetnum) (CURRENT_SCREEN, id);
345 }
346 #endif
347 
348 /***************************************************************************
349  *
350  * tgetstr(str, area)
351  *
352  * Look up string termcap capability str and return a pointer to its value,
353  * or NULL if not given.
354  *
355  ***************************************************************************/
356 
357 NCURSES_EXPORT(char *)
358 NCURSES_SP_NAME(tgetstr) (NCURSES_SP_DCLx const char *id, char **area)
359 {
360     char *result = NULL;
361 
362     T((T_CALLED("tgetstr(%s,%p)"), id, (void *) area));
363     if (HasTInfoTerminal(SP_PARM) && ValidCap(id)) {
364 	TERMTYPE2 *tp = &TerminalType(TerminalOf(SP_PARM));
365 	struct name_table_entry const *entry_ptr;
366 	int j = -1;
367 
368 	entry_ptr = _nc_find_type_entry(id, STRING, TRUE);
369 	if (entry_ptr != 0) {
370 	    j = entry_ptr->nte_index;
371 	}
372 #if NCURSES_XNAMES
373 	else {
374 	    int i;
375 	    for_each_ext_string(i, tp) {
376 		const char *capname = ExtStrname(tp, i, strcodes);
377 		if (same_tcname(id, capname) && ValidExt(capname)) {
378 		    j = i;
379 		    break;
380 		}
381 	    }
382 	}
383 #endif
384 	if (j >= 0) {
385 	    result = tp->Strings[j];
386 	    TR(TRACE_DATABASE, ("found match %d: %s", j, _nc_visbuf(result)));
387 	    /* setupterm forces canceled strings to null */
388 	    if (VALID_STRING(result)) {
389 		if (result == exit_attribute_mode
390 		    && FIX_SGR0 != 0) {
391 		    result = FIX_SGR0;
392 		    TR(TRACE_DATABASE, ("altered to : %s", _nc_visbuf(result)));
393 		}
394 		if (area != 0
395 		    && *area != 0) {
396 		    _nc_STRCPY(*area, result, 1024);
397 		    result = *area;
398 		    *area += strlen(*area) + 1;
399 		}
400 	    }
401 	}
402     }
403     returnPtr(result);
404 }
405 
406 #if NCURSES_SP_FUNCS
407 NCURSES_EXPORT(char *)
408 tgetstr(const char *id, char **area)
409 {
410     return NCURSES_SP_NAME(tgetstr) (CURRENT_SCREEN, id, area);
411 }
412 #endif
413 
414 #if NO_LEAKS
415 #undef CacheInx
416 #define CacheInx num
417 NCURSES_EXPORT(void)
418 _nc_tgetent_leak(TERMINAL *termp)
419 {
420     if (termp != 0) {
421 	int num;
422 	for (CacheInx = 0; CacheInx < TGETENT_MAX; ++CacheInx) {
423 	    if (LAST_TRM == termp) {
424 		FreeAndNull(FIX_SGR0);
425 		if (LAST_TRM != 0) {
426 		    LAST_TRM = 0;
427 		}
428 		break;
429 	    }
430 	}
431     }
432 }
433 
434 NCURSES_EXPORT(void)
435 _nc_tgetent_leaks(void)
436 {
437     int num;
438     for (CacheInx = 0; CacheInx < TGETENT_MAX; ++CacheInx) {
439 	if (LAST_TRM != 0) {
440 	    del_curterm(LAST_TRM);
441 	    _nc_tgetent_leak(LAST_TRM);
442 	}
443     }
444 }
445 #endif
446