xref: /openbsd-src/lib/libcurses/tinfo/lib_setup.c (revision a0747c9f67a4ae71ccb71e62a28d1ea19e06a63c)
1 /* $OpenBSD: lib_setup.c,v 1.13 2021/03/10 20:16:08 millert Exp $ */
2 
3 /****************************************************************************
4  * Copyright (c) 1998-2007,2008 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  * Terminal setup routines common to termcap and terminfo:
39  *
40  *		use_env(bool)
41  *		setupterm(char *, int, int *)
42  */
43 
44 #include <curses.priv.h>
45 #include <tic.h>		/* for MAX_NAME_SIZE */
46 #include <term_entry.h>
47 
48 #if SVR4_TERMIO && !defined(_POSIX_SOURCE)
49 #define _POSIX_SOURCE
50 #endif
51 
52 #if HAVE_LOCALE_H
53 #include <locale.h>
54 #endif
55 
56 #include <term.h>		/* lines, columns, cur_term */
57 
58 MODULE_ID("$Id: lib_setup.c,v 1.13 2021/03/10 20:16:08 millert Exp $")
59 
60 /****************************************************************************
61  *
62  * Terminal size computation
63  *
64  ****************************************************************************/
65 
66 #if HAVE_SIZECHANGE
67 # if !defined(sun) || !TERMIOS
68 #  if HAVE_SYS_IOCTL_H
69 #   include <sys/ioctl.h>
70 #  endif
71 # endif
72 #endif
73 
74 #if NEED_PTEM_H
75  /* On SCO, they neglected to define struct winsize in termios.h -- it's only
76   * in termio.h and ptem.h (the former conflicts with other definitions).
77   */
78 # include <sys/stream.h>
79 # include <sys/ptem.h>
80 #endif
81 
82 #if HAVE_LANGINFO_CODESET
83 #include <langinfo.h>
84 #endif
85 
86 /*
87  * SCO defines TIOCGSIZE and the corresponding struct.  Other systems (SunOS,
88  * Solaris, IRIX) define TIOCGWINSZ and struct winsize.
89  */
90 #ifdef TIOCGSIZE
91 # define IOCTL_WINSIZE TIOCGSIZE
92 # define STRUCT_WINSIZE struct ttysize
93 # define WINSIZE_ROWS(n) (int)n.ts_lines
94 # define WINSIZE_COLS(n) (int)n.ts_cols
95 #else
96 # ifdef TIOCGWINSZ
97 #  define IOCTL_WINSIZE TIOCGWINSZ
98 #  define STRUCT_WINSIZE struct winsize
99 #  define WINSIZE_ROWS(n) (int)n.ws_row
100 #  define WINSIZE_COLS(n) (int)n.ws_col
101 # endif
102 #endif
103 
104 /*
105  * Reduce explicit use of "cur_term" global variable.
106  */
107 #undef CUR
108 #define CUR termp->type.
109 
110 /*
111  * Wrap global variables in this module.
112  */
113 #if USE_REENTRANT
114 NCURSES_EXPORT(char *)
115 NCURSES_PUBLIC_VAR(ttytype) (void)
116 {
117     static char empty[] = "";
118     return cur_term ? cur_term->type.term_names : empty;
119 }
120 NCURSES_EXPORT(int *)
121 _nc_ptr_Lines(void)
122 {
123     return ptrLines();
124 }
125 NCURSES_EXPORT(int)
126 NCURSES_PUBLIC_VAR(LINES) (void)
127 {
128     return *_nc_ptr_Lines();
129 }
130 NCURSES_EXPORT(int *)
131 _nc_ptr_Cols(void)
132 {
133     return ptrCols();
134 }
135 NCURSES_EXPORT(int)
136 NCURSES_PUBLIC_VAR(COLS) (void)
137 {
138     return *_nc_ptr_Cols();
139 }
140 NCURSES_EXPORT(int)
141 NCURSES_PUBLIC_VAR(TABSIZE) (void)
142 {
143     return SP ? SP->_TABSIZE : 8;
144 }
145 #else
146 NCURSES_EXPORT_VAR(char) ttytype[NAMESIZE] = "";
147 NCURSES_EXPORT_VAR(int) LINES = 0;
148 NCURSES_EXPORT_VAR(int) COLS = 0;
149 NCURSES_EXPORT_VAR(int) TABSIZE = 0;
150 #endif
151 
152 #if NCURSES_EXT_FUNCS
153 NCURSES_EXPORT(int)
154 set_tabsize(int value)
155 {
156     int code = OK;
157 #if USE_REENTRANT
158     if (SP) {
159 	SP->_TABSIZE = value;
160     } else {
161 	code = ERR;
162     }
163 #else
164     TABSIZE = value;
165 #endif
166     return code;
167 }
168 #endif
169 
170 #if USE_SIGWINCH
171 /*
172  * If we have a pending SIGWINCH, set the flag in each screen.
173  */
174 NCURSES_EXPORT(int)
175 _nc_handle_sigwinch(SCREEN *sp)
176 {
177     SCREEN *scan;
178 
179     if (_nc_globals.have_sigwinch) {
180 	_nc_globals.have_sigwinch = 0;
181 
182 	for (each_screen(scan)) {
183 	    scan->_sig_winch = TRUE;
184 	}
185     }
186 
187     return (sp ? sp->_sig_winch : 0);
188 }
189 
190 #endif
191 
192 NCURSES_EXPORT(void)
193 use_env(bool f)
194 {
195     T((T_CALLED("use_env()")));
196     _nc_prescreen.use_env = f;
197     returnVoid;
198 }
199 
200 NCURSES_EXPORT(void)
201 _nc_get_screensize(SCREEN *sp, int *linep, int *colp)
202 /* Obtain lines/columns values from the environment and/or terminfo entry */
203 {
204     TERMINAL *termp = cur_term;
205     int my_tabsize;
206 
207     /* figure out the size of the screen */
208     T(("screen size: terminfo lines = %d columns = %d", lines, columns));
209 
210     if (!_nc_prescreen.use_env) {
211 	*linep = (int) lines;
212 	*colp = (int) columns;
213     } else {			/* usually want to query LINES and COLUMNS from environment */
214 	int value;
215 
216 	*linep = *colp = 0;
217 
218 	/* first, look for environment variables */
219 	if ((value = _nc_getenv_num("LINES")) > 0) {
220 	    *linep = value;
221 	}
222 	if ((value = _nc_getenv_num("COLUMNS")) > 0) {
223 	    *colp = value;
224 	}
225 	T(("screen size: environment LINES = %d COLUMNS = %d", *linep, *colp));
226 
227 #ifdef __EMX__
228 	if (*linep <= 0 || *colp <= 0) {
229 	    int screendata[2];
230 	    _scrsize(screendata);
231 	    *colp = screendata[0];
232 	    *linep = screendata[1];
233 	    T(("EMX screen size: environment LINES = %d COLUMNS = %d",
234 	       *linep, *colp));
235 	}
236 #endif
237 #if HAVE_SIZECHANGE
238 	/* if that didn't work, maybe we can try asking the OS */
239 	if (*linep <= 0 || *colp <= 0) {
240 	    if (isatty(cur_term->Filedes)) {
241 		STRUCT_WINSIZE size;
242 
243 		errno = 0;
244 		do {
245 		    if (ioctl(cur_term->Filedes, IOCTL_WINSIZE, &size) < 0
246 			&& errno != EINTR)
247 			goto failure;
248 		} while
249 		    (errno == EINTR);
250 
251 		/*
252 		 * Solaris lets users override either dimension with an
253 		 * environment variable.
254 		 */
255 		if (*linep <= 0)
256 		    *linep = (sp != 0 && sp->_filtered) ? 1 : WINSIZE_ROWS(size);
257 		if (*colp <= 0)
258 		    *colp = WINSIZE_COLS(size);
259 	    }
260 	    /* FALLTHRU */
261 	  failure:;
262 	}
263 #endif /* HAVE_SIZECHANGE */
264 
265 	/* if we can't get dynamic info about the size, use static */
266 	if (*linep <= 0) {
267 	    *linep = (int) lines;
268 	}
269 	if (*colp <= 0) {
270 	    *colp = (int) columns;
271 	}
272 
273 	/* the ultimate fallback, assume fixed 24x80 size */
274 	if (*linep <= 0) {
275 	    *linep = 24;
276 	}
277 	if (*colp <= 0) {
278 	    *colp = 80;
279 	}
280 
281 	/*
282 	 * Put the derived values back in the screen-size caps, so
283 	 * tigetnum() and tgetnum() will do the right thing.
284 	 */
285 	lines = (short) (*linep);
286 	columns = (short) (*colp);
287     }
288 
289     T(("screen size is %dx%d", *linep, *colp));
290 
291     if (VALID_NUMERIC(init_tabs))
292 	my_tabsize = (int) init_tabs;
293     else
294 	my_tabsize = 8;
295 
296 #if USE_REENTRANT
297     if (sp != 0)
298 	sp->_TABSIZE = my_tabsize;
299 #else
300     TABSIZE = my_tabsize;
301 #endif
302     T(("TABSIZE = %d", TABSIZE));
303 }
304 
305 #if USE_SIZECHANGE
306 NCURSES_EXPORT(void)
307 _nc_update_screensize(SCREEN *sp)
308 {
309     TERMINAL *termp = cur_term;
310     int old_lines = lines;
311     int new_lines;
312     int old_cols = columns;
313     int new_cols;
314 
315     _nc_get_screensize(sp, &new_lines, &new_cols);
316 
317     /*
318      * See is_term_resized() and resizeterm().
319      * We're doing it this way because those functions belong to the upper
320      * ncurses library, while this resides in the lower terminfo library.
321      */
322     if (sp != 0
323 	&& sp->_resize != 0) {
324 	if ((new_lines != old_lines) || (new_cols != old_cols)) {
325 	    sp->_resize(new_lines, new_cols);
326 	} else if (sp->_sig_winch && (sp->_ungetch != 0)) {
327 	    sp->_ungetch(SP, KEY_RESIZE);	/* so application can know this */
328 	}
329 	sp->_sig_winch = FALSE;
330     }
331 }
332 #endif
333 
334 /****************************************************************************
335  *
336  * Terminal setup
337  *
338  ****************************************************************************/
339 
340 #define ret_error(code, fmt, arg)	if (errret) {\
341 					    *errret = code;\
342 					    returnCode(ERR);\
343 					} else {\
344 					    fprintf(stderr, fmt, arg);\
345 					    exit(EXIT_FAILURE);\
346 					}
347 
348 #define ret_error0(code, msg)		if (errret) {\
349 					    *errret = code;\
350 					    returnCode(ERR);\
351 					} else {\
352 					    fprintf(stderr, msg);\
353 					    exit(EXIT_FAILURE);\
354 					}
355 
356 #if USE_DATABASE || USE_TERMCAP
357 /*
358  * Return 1 if entry found, 0 if not found, -1 if database not accessible,
359  * just like tgetent().
360  */
361 static int
362 grab_entry(const char *const tn, TERMTYPE *const tp)
363 {
364     char filename[PATH_MAX];
365     int status = _nc_read_entry(tn, filename, tp);
366 
367     /*
368      * If we have an entry, force all of the cancelled strings to null
369      * pointers so we don't have to test them in the rest of the library.
370      * (The terminfo compiler bypasses this logic, since it must know if
371      * a string is cancelled, for merging entries).
372      */
373     if (status == TGETENT_YES) {
374 	unsigned n;
375 	for_each_boolean(n, tp) {
376 	    if (!VALID_BOOLEAN(tp->Booleans[n]))
377 		tp->Booleans[n] = FALSE;
378 	}
379 	for_each_string(n, tp) {
380 	    if (tp->Strings[n] == CANCELLED_STRING)
381 		tp->Strings[n] = ABSENT_STRING;
382 	}
383     }
384     return (status);
385 }
386 #endif
387 
388 /*
389 **	do_prototype()
390 **
391 **	Take the real command character out of the CC environment variable
392 **	and substitute it in for the prototype given in 'command_character'.
393 */
394 static void
395 do_prototype(TERMINAL * termp)
396 {
397     unsigned i;
398     char CC;
399     char proto;
400     char *tmp;
401 
402     if ((tmp = getenv("CC")) != 0) {
403 	if ((CC = *tmp) != 0) {
404 	    proto = *command_character;
405 
406 	    for_each_string(i, &(termp->type)) {
407 		for (tmp = termp->type.Strings[i]; *tmp; tmp++) {
408 		    if (*tmp == proto)
409 			*tmp = CC;
410 		}
411 	    }
412 	}
413     }
414 }
415 
416 /*
417  * Find the locale which is in effect.
418  */
419 NCURSES_EXPORT(char *)
420 _nc_get_locale(void)
421 {
422     char *env;
423 #if HAVE_LOCALE_H
424     /*
425      * This is preferable to using getenv() since it ensures that we are using
426      * the locale which was actually initialized by the application.
427      */
428     env = setlocale(LC_CTYPE, 0);
429 #else
430     if (((env = getenv("LC_ALL")) != 0 && *env != '\0')
431 	|| ((env = getenv("LC_CTYPE")) != 0 && *env != '\0')
432 	|| ((env = getenv("LANG")) != 0 && *env != '\0')) {
433 	;
434     }
435 #endif
436     T(("_nc_get_locale %s", _nc_visbuf(env)));
437     return env;
438 }
439 
440 /*
441  * Check if we are running in a UTF-8 locale.
442  */
443 NCURSES_EXPORT(int)
444 _nc_unicode_locale(void)
445 {
446     int result = 0;
447 #if HAVE_LANGINFO_CODESET
448     char *env = nl_langinfo(CODESET);
449     result = !strcmp(env, "UTF-8");
450     T(("_nc_unicode_locale(%s) ->%d", env, result));
451 #else
452     char *env = _nc_get_locale();
453     if (env != 0) {
454 	if (strstr(env, ".UTF-8") != 0) {
455 	    result = 1;
456 	    T(("_nc_unicode_locale(%s) ->%d", env, result));
457 	}
458     }
459 #endif
460     return result;
461 }
462 
463 #define CONTROL_N(s) ((s) != 0 && strstr(s, "\016") != 0)
464 #define CONTROL_O(s) ((s) != 0 && strstr(s, "\017") != 0)
465 
466 /*
467  * Check for known broken cases where a UTF-8 locale breaks the alternate
468  * character set.
469  */
470 NCURSES_EXPORT(int)
471 _nc_locale_breaks_acs(TERMINAL * termp)
472 {
473     char *env;
474 
475     if ((env = getenv("NCURSES_NO_UTF8_ACS")) != 0) {
476 	return atoi(env);
477     } else if ((env = getenv("TERM")) != 0) {
478 	if (strstr(env, "linux"))
479 	    return 1;		/* always broken */
480 	if (strstr(env, "screen") != 0
481 	    && ((env = getenv("TERMCAP")) != 0
482 		&& strstr(env, "screen") != 0)
483 	    && strstr(env, "hhII00") != 0) {
484 	    if (CONTROL_N(enter_alt_charset_mode) ||
485 		CONTROL_O(enter_alt_charset_mode) ||
486 		CONTROL_N(set_attributes) ||
487 		CONTROL_O(set_attributes))
488 		return 1;
489 	}
490     }
491     return 0;
492 }
493 
494 /*
495  * This entrypoint is called from tgetent() to allow a special case of reusing
496  * the same TERMINAL data (see comment).
497  */
498 NCURSES_EXPORT(int)
499 _nc_setupterm(NCURSES_CONST char *tname, int Filedes, int *errret, bool reuse)
500 {
501     TERMINAL *termp;
502     int status;
503 
504     START_TRACE();
505     T((T_CALLED("setupterm(%s,%d,%p)"), _nc_visbuf(tname), Filedes, errret));
506 
507     if (tname == 0) {
508 	tname = getenv("TERM");
509 	if (tname == 0 || *tname == '\0') {
510 	    ret_error0(TGETENT_ERR, "TERM environment variable not set.\n");
511 	}
512     }
513 
514     if (strlen(tname) > MAX_NAME_SIZE) {
515 	ret_error(TGETENT_ERR,
516 		  "TERM environment must be <= %d characters.\n",
517 		  MAX_NAME_SIZE);
518     }
519 
520     T(("your terminal name is %s", tname));
521 
522     /*
523      * Allow output redirection.  This is what SVr3 does.  If stdout is
524      * directed to a file, screen updates go to standard error.
525      */
526     if (Filedes == STDOUT_FILENO && !isatty(Filedes))
527 	Filedes = STDERR_FILENO;
528 
529     /*
530      * Check if we have already initialized to use this terminal.  If so, we
531      * do not need to re-read the terminfo entry, or obtain TTY settings.
532      *
533      * This is an improvement on SVr4 curses.  If an application mixes curses
534      * and termcap calls, it may call both initscr and tgetent.  This is not
535      * really a good thing to do, but can happen if someone tries using ncurses
536      * with the readline library.  The problem we are fixing is that when
537      * tgetent calls setupterm, the resulting Ottyb struct in cur_term is
538      * zeroed.  A subsequent call to endwin uses the zeroed terminal settings
539      * rather than the ones saved in initscr.  So we check if cur_term appears
540      * to contain terminal settings for the same output file as our current
541      * call - and copy those terminal settings.  (SVr4 curses does not do this,
542      * however applications that are working around the problem will still work
543      * properly with this feature).
544      */
545     if (reuse
546 	&& (termp = cur_term) != 0
547 	&& termp->Filedes == Filedes
548 	&& termp->_termname != 0
549 	&& !strcmp(termp->_termname, tname)
550 	&& _nc_name_match(termp->type.term_names, tname, "|")) {
551 	T(("reusing existing terminal information and mode-settings"));
552     } else {
553 
554 	termp = typeCalloc(TERMINAL, 1);
555 
556 	if (termp == 0) {
557 	    ret_error0(TGETENT_ERR,
558 		       "Not enough memory to create terminal structure.\n");
559 	}
560 #if USE_DATABASE || USE_TERMCAP
561 	status = grab_entry(tname, &termp->type);
562 #else
563 	status = TGETENT_NO;
564 #endif
565 
566 	/* try fallback list if entry on disk */
567 	if (status != TGETENT_YES) {
568 	    const TERMTYPE *fallback = _nc_fallback(tname);
569 
570 	    if (fallback) {
571 		termp->type = *fallback;
572 		status = TGETENT_YES;
573 	    }
574 	}
575 
576 	if (status != TGETENT_YES) {
577 	    del_curterm(termp);
578 	    if (status == TGETENT_ERR) {
579 		ret_error0(status, "terminals database is inaccessible\n");
580 	    } else if (status == TGETENT_NO) {
581 		ret_error(status, "'%s': unknown terminal type.\n", tname);
582 	    }
583 	}
584 #if !USE_REENTRANT
585 	strncpy(ttytype, termp->type.term_names, NAMESIZE - 1);
586 	ttytype[NAMESIZE - 1] = '\0';
587 #endif
588 
589 	termp->Filedes = Filedes;
590 	termp->_termname = strdup(tname);
591 
592 	set_curterm(termp);
593 
594 	if (command_character && getenv("CC"))
595 	    do_prototype(termp);
596 
597 	/*
598 	 * If an application calls setupterm() rather than initscr() or
599 	 * newterm(), we will not have the def_prog_mode() call in
600 	 * _nc_setupscreen().  Do it now anyway, so we can initialize the
601 	 * baudrate.
602 	 */
603 	if (isatty(Filedes)) {
604 	    def_prog_mode();
605 	    baudrate();
606 	}
607     }
608 
609     /*
610      * We should always check the screensize, just in case.
611      */
612     _nc_get_screensize(SP, ptrLines(), ptrCols());
613 
614     if (errret)
615 	*errret = TGETENT_YES;
616 
617     if (generic_type) {
618 	ret_error(TGETENT_NO, "'%s': I need something more specific.\n", tname);
619     }
620     if (hard_copy) {
621 	ret_error(TGETENT_YES, "'%s': I can't handle hardcopy terminals.\n", tname);
622     }
623     returnCode(OK);
624 }
625 
626 /*
627  *	setupterm(termname, Filedes, errret)
628  *
629  *	Find and read the appropriate object file for the terminal
630  *	Make cur_term point to the structure.
631  */
632 NCURSES_EXPORT(int)
633 setupterm(NCURSES_CONST char *tname, int Filedes, int *errret)
634 {
635     return _nc_setupterm(tname, Filedes, errret, FALSE);
636 }
637