xref: /openbsd/lib/libcurses/base/lib_set_term.c (revision 379777c0)
1 /* $OpenBSD: lib_set_term.c,v 1.15 2023/10/17 09:52:09 nicm Exp $ */
2 
3 /****************************************************************************
4  * Copyright 2018-2021,2022 Thomas E. Dickey                                *
5  * Copyright 1998-2016,2017 Free Software Foundation, Inc.                  *
6  *                                                                          *
7  * Permission is hereby granted, free of charge, to any person obtaining a  *
8  * copy of this software and associated documentation files (the            *
9  * "Software"), to deal in the Software without restriction, including      *
10  * without limitation the rights to use, copy, modify, merge, publish,      *
11  * distribute, distribute with modifications, sublicense, and/or sell       *
12  * copies of the Software, and to permit persons to whom the Software is    *
13  * furnished to do so, subject to the following conditions:                 *
14  *                                                                          *
15  * The above copyright notice and this permission notice shall be included  *
16  * in all copies or substantial portions of the Software.                   *
17  *                                                                          *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
21  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
24  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
25  *                                                                          *
26  * Except as contained in this notice, the name(s) of the above copyright   *
27  * holders shall not be used in advertising or otherwise to promote the     *
28  * sale, use or other dealings in this Software without prior written       *
29  * authorization.                                                           *
30  ****************************************************************************/
31 
32 /****************************************************************************
33  *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
34  *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
35  *     and: Thomas E. Dickey                        1996-on                 *
36  *     and: Juergen Pfeifer                         2009                    *
37  ****************************************************************************/
38 
39 /*
40 **	lib_set_term.c
41 **
42 **	The routine set_term().
43 **
44 */
45 
46 #define NEW_PAIR_INTERNAL 1
47 
48 #include <curses.priv.h>
49 #include <tic.h>
50 #include <new_pair.h>
51 
52 #if USE_GPM_SUPPORT
53 #ifdef HAVE_LIBDL
54 /* use dynamic loader to avoid linkage dependency */
55 #include <dlfcn.h>
56 #endif
57 #endif
58 
59 #undef CUR
60 #define CUR SP_TERMTYPE
61 
62 MODULE_ID("$Id: lib_set_term.c,v 1.15 2023/10/17 09:52:09 nicm Exp $")
63 
64 #ifdef USE_TERM_DRIVER
65 #define MaxColors      InfoOf(sp).maxcolors
66 #define NumLabels      InfoOf(sp).numlabels
67 #else
68 #define MaxColors      max_colors
69 #define NumLabels      num_labels
70 #endif
71 
72 NCURSES_EXPORT(SCREEN *)
73 set_term(SCREEN *screenp)
74 {
75     SCREEN *oldSP;
76     SCREEN *newSP;
77 
78     T((T_CALLED("set_term(%p)"), (void *) screenp));
79 
80     _nc_lock_global(curses);
81 
82     oldSP = CURRENT_SCREEN;
83     _nc_set_screen(screenp);
84     newSP = screenp;
85 
86     if (newSP != 0) {
87 	TINFO_SET_CURTERM(newSP, newSP->_term);
88 #if !USE_REENTRANT
89 	curscr = CurScreen(newSP);
90 	newscr = NewScreen(newSP);
91 	stdscr = StdScreen(newSP);
92 	COLORS = newSP->_color_count;
93 	COLOR_PAIRS = newSP->_pair_count;
94 #endif
95     } else {
96 	TINFO_SET_CURTERM(oldSP, 0);
97 #if !USE_REENTRANT
98 	curscr = 0;
99 	newscr = 0;
100 	stdscr = 0;
101 	COLORS = 0;
102 	COLOR_PAIRS = 0;
103 #endif
104     }
105 
106     _nc_unlock_global(curses);
107 
108     T((T_RETURN("%p"), (void *) oldSP));
109     return (oldSP);
110 }
111 
112 static void
113 _nc_free_keytry(TRIES * kt)
114 {
115     if (kt != 0) {
116 	_nc_free_keytry(kt->child);
117 	_nc_free_keytry(kt->sibling);
118 	free(kt);
119     }
120 }
121 
122 static bool
123 delink_screen(SCREEN *sp)
124 {
125     SCREEN *last = 0;
126     SCREEN *temp;
127     bool result = FALSE;
128 
129     for (each_screen(temp)) {
130 	if (temp == sp) {
131 	    if (last)
132 		last->_next_screen = sp->_next_screen;
133 	    else
134 		_nc_screen_chain = sp->_next_screen;
135 	    result = TRUE;
136 	    break;
137 	}
138 	last = temp;
139     }
140     return result;
141 }
142 
143 /*
144  * Free the storage associated with the given SCREEN sp.
145  */
146 NCURSES_EXPORT(void)
147 delscreen(SCREEN *sp)
148 {
149 
150     T((T_CALLED("delscreen(%p)"), (void *) sp));
151 
152     _nc_lock_global(curses);
153     if (delink_screen(sp)) {
154 	WINDOWLIST *wl;
155 	bool is_current = (sp == CURRENT_SCREEN);
156 
157 #ifdef USE_SP_RIPOFF
158 	if (safe_ripoff_sp && safe_ripoff_sp != safe_ripoff_stack) {
159 	    ripoff_t *rop;
160 	    for (rop = safe_ripoff_stack;
161 		 rop != safe_ripoff_sp && (rop - safe_ripoff_stack) < N_RIPS;
162 		 rop++) {
163 		if (rop->win) {
164 		    (void) delwin(rop->win);
165 		    rop->win = 0;
166 		}
167 	    }
168 	}
169 #endif
170 
171 	/* delete all of the windows in this screen */
172       rescan:
173 	for (each_window(sp, wl)) {
174 	    if (_nc_freewin(&(wl->win)) == OK) {
175 		goto rescan;
176 	    }
177 	}
178 
179 	if (sp->_slk != 0) {
180 
181 	    if (sp->_slk->ent != 0) {
182 		int i;
183 
184 		for (i = 0; i < sp->_slk->labcnt; ++i) {
185 		    FreeIfNeeded(sp->_slk->ent[i].ent_text);
186 		    FreeIfNeeded(sp->_slk->ent[i].form_text);
187 		}
188 		free(sp->_slk->ent);
189 	    }
190 	    free(sp->_slk);
191 	    sp->_slk = 0;
192 	}
193 
194 	_nc_free_keytry(sp->_keytry);
195 	sp->_keytry = 0;
196 
197 	_nc_free_keytry(sp->_key_ok);
198 	sp->_key_ok = 0;
199 
200 	FreeIfNeeded(sp->_current_attr);
201 
202 	_nc_free_ordered_pairs(sp);
203 	FreeIfNeeded(sp->_color_table);
204 	FreeIfNeeded(sp->_color_pairs);
205 
206 	FreeIfNeeded(sp->_oldnum_list);
207 	FreeIfNeeded(sp->oldhash);
208 	FreeIfNeeded(sp->newhash);
209 	FreeIfNeeded(sp->hashtab);
210 
211 	FreeIfNeeded(sp->_acs_map);
212 	FreeIfNeeded(sp->_screen_acs_map);
213 
214 	NCURSES_SP_NAME(_nc_flush) (NCURSES_SP_ARG);
215 	NCURSES_SP_NAME(del_curterm) (NCURSES_SP_ARGx sp->_term);
216 	FreeIfNeeded(sp->out_buffer);
217 	if (_nc_find_prescr() == sp) {
218 	    _nc_forget_prescr();
219 	}
220 #if USE_GPM_SUPPORT
221 #ifdef HAVE_LIBDL
222 	if (sp->_dlopen_gpm != 0) {
223 	    dlclose(sp->_dlopen_gpm);
224 	    sp->_dlopen_gpm = 0;
225 	}
226 #endif
227 #endif /* USE_GPM_SUPPORT */
228 	free(sp);
229 
230 	/*
231 	 * If this was the current screen, reset everything that the
232 	 * application might try to use (except cur_term, which may have
233 	 * multiple references in different screens).
234 	 */
235 	if (is_current) {
236 #if !USE_REENTRANT
237 	    curscr = 0;
238 	    newscr = 0;
239 	    stdscr = 0;
240 	    COLORS = 0;
241 	    COLOR_PAIRS = 0;
242 #endif
243 	    _nc_set_screen(0);
244 #if USE_WIDEC_SUPPORT
245 	    if (SP == 0) {
246 		FreeIfNeeded(_nc_wacs);
247 		_nc_wacs = 0;
248 	    }
249 #endif
250 	} else {
251 	    set_term(CURRENT_SCREEN);
252 	}
253     }
254     _nc_unlock_global(curses);
255 
256     returnVoid;
257 }
258 
259 static bool
260 no_mouse_event(SCREEN *sp GCC_UNUSED)
261 {
262     return FALSE;
263 }
264 
265 static bool
266 no_mouse_inline(SCREEN *sp GCC_UNUSED)
267 {
268     return FALSE;
269 }
270 
271 static bool
272 no_mouse_parse(SCREEN *sp GCC_UNUSED, int code GCC_UNUSED)
273 {
274     return TRUE;
275 }
276 
277 static void
278 no_mouse_resume(SCREEN *sp GCC_UNUSED)
279 {
280 }
281 
282 static void
283 no_mouse_wrap(SCREEN *sp GCC_UNUSED)
284 {
285 }
286 
287 #if NCURSES_EXT_FUNCS && USE_COLORFGBG
288 static const char *
289 extract_fgbg(const char *src, int *result)
290 {
291     const char *dst = 0;
292     char *tmp = 0;
293     long value = strtol(src, &tmp, 0);
294 
295     if ((dst = tmp) == 0) {
296 	dst = src;
297     } else if (value >= 0) {
298 	*result = (int) value;
299     }
300     while (*dst != 0 && *dst != ';')
301 	dst++;
302     if (*dst == ';')
303 	dst++;
304     return dst;
305 }
306 #endif
307 
308 #define ReturnScreenError() do { _nc_set_screen(0); \
309                             returnCode(ERR); } while (0)
310 
311 /* OS-independent screen initializations */
312 NCURSES_EXPORT(int)
313 NCURSES_SP_NAME(_nc_setupscreen) (
314 #if NCURSES_SP_FUNCS
315 				     SCREEN **spp,
316 #endif
317 				     int slines,
318 				     int scolumns,
319 				     FILE *output,
320 				     int filtered,
321 				     int slk_format)
322 {
323 #ifndef USE_TERM_DRIVER
324     static const TTY null_TTY;	/* all zeros iff uninitialized */
325 #endif
326     char *env;
327     int bottom_stolen = 0;
328     SCREEN *sp;
329 #ifndef USE_TERM_DRIVER
330     bool support_cookies = USE_XMC_SUPPORT;
331 #endif
332 
333     T((T_CALLED("_nc_setupscreen(%d, %d, %p, %d, %d)"),
334        slines, scolumns, (void *) output, filtered, slk_format));
335 
336     assert(CURRENT_SCREEN == 0);	/* has been reset in newterm() ! */
337 
338 #if NCURSES_SP_FUNCS
339     assert(spp != 0);
340     sp = *spp;
341 
342     if (!sp) {
343 	sp = _nc_alloc_screen_sp();
344 	T(("_nc_alloc_screen_sp %p", (void *) sp));
345 	*spp = sp;
346     }
347     if (sp == NULL) {
348 	ReturnScreenError();
349     }
350     if ((sp->_acs_map = typeCalloc(chtype, ACS_LEN)) == NULL) {
351 	ReturnScreenError();
352     }
353     if ((sp->_screen_acs_map = typeCalloc(bool, ACS_LEN)) == NULL) {
354 	free(sp->_acs_map);
355 	ReturnScreenError();
356     }
357 
358     T(("created SP %p", (void *) sp));
359     sp->_next_screen = _nc_screen_chain;
360     _nc_screen_chain = sp;
361 
362     if ((sp->_current_attr = typeCalloc(NCURSES_CH_T, 1)) == 0) {
363 	ReturnScreenError();
364     }
365 #else
366     if (!_nc_alloc_screen()
367 	|| ((SP->_acs_map = typeCalloc(chtype, ACS_LEN)) == 0)
368 	|| ((SP->_screen_acs_map = typeCalloc(bool, ACS_LEN)) == 0)) {
369 	returnCode(ERR);
370     }
371 
372     T(("created SP %p", (void *) SP));
373 
374     sp = SP;			/* fixup so SET_LINES and SET_COLS works */
375     sp->_next_screen = _nc_screen_chain;
376     _nc_screen_chain = sp;
377 
378     if ((sp->_current_attr = typeCalloc(NCURSES_CH_T, 1)) == 0) {
379 	returnCode(ERR);
380     }
381 #endif
382 
383     /*
384      * We should always check the screensize, just in case.
385      */
386     _nc_set_screen(sp);
387     sp->_term = cur_term;
388 #ifdef USE_TERM_DRIVER
389     TCBOf(sp)->csp = sp;
390     _nc_get_screensize(sp, sp->_term, &slines, &scolumns);
391 #else
392     _nc_get_screensize(sp, &slines, &scolumns);
393 #endif
394     SET_LINES(slines);
395     SET_COLS(scolumns);
396 
397     T((T_CREATE("screen %s %dx%d"),
398        NCURSES_SP_NAME(termname) (NCURSES_SP_ARG), slines, scolumns));
399 
400     sp->_filtered = filtered;
401 
402     /* implement filter mode */
403     if (filtered) {
404 	slines = 1;
405 	SET_LINES(slines);
406 #ifdef USE_TERM_DRIVER
407 	CallDriver(sp, td_setfilter);
408 #else
409 	/* *INDENT-EQLS* */
410 	clear_screen     = ABSENT_STRING;
411 	cursor_address   = ABSENT_STRING;
412 	cursor_down      = ABSENT_STRING;
413 	cursor_up        = ABSENT_STRING;
414 	parm_down_cursor = ABSENT_STRING;
415 	parm_up_cursor   = ABSENT_STRING;
416 	row_address      = ABSENT_STRING;
417 	cursor_home      = carriage_return;
418 
419 	if (back_color_erase)
420 	    clr_eos = ABSENT_STRING;
421 
422 #endif
423 	T(("filter screensize %dx%d", slines, scolumns));
424     }
425 #ifdef __DJGPP__
426     T(("setting output mode to binary"));
427     fflush(output);
428     setmode(output, O_BINARY);
429 #endif
430 #if defined(EXP_WIN32_DRIVER)
431     T(("setting output mode to binary"));
432     fflush(output);
433     _setmode(fileno(output), _O_BINARY);
434 #endif
435     sp->_lines = (NCURSES_SIZE_T) slines;
436     sp->_lines_avail = (NCURSES_SIZE_T) slines;
437     sp->_columns = (NCURSES_SIZE_T) scolumns;
438 
439     fflush(output);
440     sp->_ofd = output ? fileno(output) : -1;
441     sp->_ofp = output;
442 #if defined(EXP_WIN32_DRIVER)
443     if (output)
444 	_setmode(fileno(output), _O_BINARY);
445 #endif
446     sp->out_limit = (size_t) ((2 + slines) * (6 + scolumns));
447     if ((sp->out_buffer = malloc(sp->out_limit)) == 0)
448 	sp->out_limit = 0;
449     sp->out_inuse = 0;
450 
451     SP_PRE_INIT(sp);
452     SetNoPadding(sp);
453 
454 #if NCURSES_EXT_FUNCS
455     sp->_default_color = FALSE;
456     sp->_has_sgr_39_49 = FALSE;
457 
458     /*
459      * Set our assumption of the terminal's default foreground and background
460      * colors.  The curs_color man-page states that we can assume that the
461      * background is black.  The origin of this assumption appears to be
462      * terminals that displayed colored text, but no colored backgrounds, e.g.,
463      * the first colored terminals around 1980.  More recent ones with better
464      * technology can display not only colored backgrounds, but all
465      * combinations.  So a terminal might be something other than "white" on
466      * black (green/black looks monochrome too), but black on white or even
467      * on ivory.
468      *
469      * White-on-black is the simplest thing to use for monochrome.  Almost
470      * all applications that use color paint both text and background, so
471      * the distinction is moot.  But a few do not - which is why we leave this
472      * configurable (a better solution is to use assume_default_colors() for
473      * the rare applications that do require that sort of appearance, since
474      * is appears that more users expect to be able to make a white-on-black
475      * or black-on-white display under control of the application than not).
476      */
477 #ifdef USE_ASSUMED_COLOR
478     sp->_default_fg = COLOR_WHITE;
479     sp->_default_bg = COLOR_BLACK;
480 #else
481     sp->_default_fg = COLOR_DEFAULT;
482     sp->_default_bg = COLOR_DEFAULT;
483 #endif
484 
485     /*
486      * Allow those assumed/default color assumptions to be overridden at
487      * runtime:
488      */
489     if ((env = getenv("NCURSES_ASSUMED_COLORS")) != 0) {
490 	int fg, bg;
491 	char sep1, sep2;
492 	int count = sscanf(env, "%d%c%d%c", &fg, &sep1, &bg, &sep2);
493 	if (count >= 1) {
494 	    sp->_default_fg = ((fg >= 0 && fg < MaxColors) ? fg : COLOR_DEFAULT);
495 	    if (count >= 3) {
496 		sp->_default_bg = ((bg >= 0 && bg < MaxColors) ? bg : COLOR_DEFAULT);
497 	    }
498 	    TR(TRACE_CHARPUT | TRACE_MOVE,
499 	       ("from environment assumed fg=%d, bg=%d",
500 		sp->_default_fg,
501 		sp->_default_bg));
502 	}
503     }
504 #if USE_COLORFGBG
505     /*
506      * If rxvt's $COLORFGBG variable is set, use it to specify the assumed
507      * default colors.  Note that rxvt (mis)uses bold colors, equating a bold
508      * color to that value plus 8.  We'll only use the non-bold color for now -
509      * decide later if it is worth having default attributes as well.
510      */
511     if (getenv("COLORFGBG") != 0) {
512 	const char *p = getenv("COLORFGBG");
513 	TR(TRACE_CHARPUT | TRACE_MOVE, ("decoding COLORFGBG %s", p));
514 	p = extract_fgbg(p, &(sp->_default_fg));
515 	p = extract_fgbg(p, &(sp->_default_bg));
516 	if (*p)			/* assume rxvt was compiled with xpm support */
517 	    extract_fgbg(p, &(sp->_default_bg));
518 	TR(TRACE_CHARPUT | TRACE_MOVE, ("decoded fg=%d, bg=%d",
519 					sp->_default_fg, sp->_default_bg));
520 	if (sp->_default_fg >= MaxColors) {
521 	    if (set_a_foreground != ABSENT_STRING
522 		&& !strcmp(set_a_foreground, "\033[3%p1%dm")) {
523 		set_a_foreground = strdup("\033[3%?%p1%{8}%>%t9%e%p1%d%;m");
524 	    } else {
525 		sp->_default_fg %= MaxColors;
526 	    }
527 	}
528 	if (sp->_default_bg >= MaxColors) {
529 	    if (set_a_background != ABSENT_STRING
530 		&& !strcmp(set_a_background, "\033[4%p1%dm")) {
531 		set_a_background = strdup("\033[4%?%p1%{8}%>%t9%e%p1%d%;m");
532 	    } else {
533 		sp->_default_bg %= MaxColors;
534 	    }
535 	}
536     }
537 #endif
538 #endif /* NCURSES_EXT_FUNCS */
539 
540     sp->_maxclick = DEFAULT_MAXCLICK;
541     sp->_mouse_event = no_mouse_event;
542     sp->_mouse_inline = no_mouse_inline;
543     sp->_mouse_parse = no_mouse_parse;
544     sp->_mouse_resume = no_mouse_resume;
545     sp->_mouse_wrap = no_mouse_wrap;
546     sp->_mouse_fd = -1;
547 
548     /*
549      * If we've no magic cookie support, we suppress attributes that xmc would
550      * affect, i.e., the attributes that affect the rendition of a space.
551      */
552     sp->_ok_attributes = NCURSES_SP_NAME(termattrs) (NCURSES_SP_ARG);
553     if (NCURSES_SP_NAME(has_colors) (NCURSES_SP_ARG)) {
554 	sp->_ok_attributes |= A_COLOR;
555     }
556 #ifdef USE_TERM_DRIVER
557     _nc_cookie_init(sp);
558 #else
559 #if USE_XMC_SUPPORT
560     /*
561      * If we have no magic-cookie support compiled-in, or if it is suppressed
562      * in the environment, reset the support-flag.
563      */
564     if (magic_cookie_glitch >= 0) {
565 	if (getenv("NCURSES_NO_MAGIC_COOKIE") != 0) {
566 	    support_cookies = FALSE;
567 	}
568     }
569 #endif
570 
571     if (!support_cookies && magic_cookie_glitch >= 0) {
572 	T(("will disable attributes to work w/o magic cookies"));
573     }
574 
575     if (magic_cookie_glitch > 0) {	/* tvi, wyse */
576 
577 	sp->_xmc_triggers = sp->_ok_attributes & XMC_CONFLICT;
578 #if 0
579 	/*
580 	 * We "should" treat colors as an attribute.  The wyse350 (and its
581 	 * clones) appear to be the only ones that have both colors and magic
582 	 * cookies.
583 	 */
584 	if (has_colors()) {
585 	    sp->_xmc_triggers |= A_COLOR;
586 	}
587 #endif
588 	sp->_xmc_suppress = sp->_xmc_triggers & (chtype) ~(A_BOLD);
589 
590 	T(("magic cookie attributes %s", _traceattr(sp->_xmc_suppress)));
591 	/*
592 	 * Supporting line-drawing may be possible.  But make the regular
593 	 * video attributes work first.
594 	 */
595 	acs_chars = ABSENT_STRING;
596 	ena_acs = ABSENT_STRING;
597 	enter_alt_charset_mode = ABSENT_STRING;
598 	exit_alt_charset_mode = ABSENT_STRING;
599 #if USE_XMC_SUPPORT
600 	/*
601 	 * To keep the cookie support simple, suppress all of the optimization
602 	 * hooks except for clear_screen and the cursor addressing.
603 	 */
604 	if (support_cookies) {
605 	    clr_eol = ABSENT_STRING;
606 	    clr_eos = ABSENT_STRING;
607 	    set_attributes = ABSENT_STRING;
608 	}
609 #endif
610     } else if (magic_cookie_glitch == 0) {	/* hpterm */
611     }
612 
613     /*
614      * If magic cookies are not supported, cancel the strings that set
615      * video attributes.
616      */
617     if (!support_cookies && magic_cookie_glitch >= 0) {
618 	magic_cookie_glitch = ABSENT_NUMERIC;
619 	set_attributes = ABSENT_STRING;
620 	enter_blink_mode = ABSENT_STRING;
621 	enter_bold_mode = ABSENT_STRING;
622 	enter_dim_mode = ABSENT_STRING;
623 	enter_reverse_mode = ABSENT_STRING;
624 	enter_standout_mode = ABSENT_STRING;
625 	enter_underline_mode = ABSENT_STRING;
626     }
627 
628     /* initialize normal acs before wide, since we use mapping in the latter */
629 #if !USE_WIDEC_SUPPORT
630     if (_nc_unicode_locale() && _nc_locale_breaks_acs(sp->_term)) {
631 	acs_chars = NULL;
632 	ena_acs = NULL;
633 	enter_alt_charset_mode = NULL;
634 	exit_alt_charset_mode = NULL;
635 	set_attributes = NULL;
636     }
637 #endif
638 #endif
639 
640     NCURSES_SP_NAME(_nc_init_acs) (NCURSES_SP_ARG);
641 #if USE_WIDEC_SUPPORT
642     sp->_screen_unicode = _nc_unicode_locale();
643     if (_nc_wacs == 0) {
644 	_nc_init_wacs();
645     }
646     if (_nc_wacs == 0) {
647 	ReturnScreenError();
648     }
649 
650     sp->_screen_acs_fix = (sp->_screen_unicode
651 			   && _nc_locale_breaks_acs(sp->_term));
652 #endif
653     env = _nc_get_locale();
654     sp->_legacy_coding = ((env == 0)
655 			  || !strcmp(env, "C")
656 			  || !strcmp(env, "POSIX"));
657     T(("legacy-coding %d", sp->_legacy_coding));
658 
659     sp->_nc_sp_idcok = TRUE;
660     sp->_nc_sp_idlok = FALSE;
661 
662     sp->oldhash = 0;
663     sp->newhash = 0;
664 
665     T(("creating newscr"));
666     NewScreen(sp) = NCURSES_SP_NAME(newwin) (NCURSES_SP_ARGx slines, scolumns,
667 					     0, 0);
668     if (NewScreen(sp) == 0) {
669 	ReturnScreenError();
670     }
671     T(("creating curscr"));
672     CurScreen(sp) = NCURSES_SP_NAME(newwin) (NCURSES_SP_ARGx slines, scolumns,
673 					     0, 0);
674     if (CurScreen(sp) == 0) {
675 	ReturnScreenError();
676     }
677 #if !USE_REENTRANT
678     newscr = NewScreen(sp);
679     curscr = CurScreen(sp);
680 #endif
681 #if USE_SIZECHANGE
682     sp->_resize = NCURSES_SP_NAME(resizeterm);
683     sp->_ungetch = safe_ungetch;
684 #endif
685 
686     NewScreen(sp)->_clear = TRUE;
687     CurScreen(sp)->_clear = FALSE;
688 
689     /*
690      * Get the current tty-modes. setupterm() may already have done this,
691      * unless we use the term-driver.
692      */
693 #ifndef USE_TERM_DRIVER
694     if (cur_term != 0 &&
695 	!memcmp(&cur_term->Ottyb, &null_TTY, sizeof(TTY)))
696 #endif
697     {
698 	NCURSES_SP_NAME(def_shell_mode) (NCURSES_SP_ARG);
699 	NCURSES_SP_NAME(def_prog_mode) (NCURSES_SP_ARG);
700     }
701 
702     if (safe_ripoff_sp && safe_ripoff_sp != safe_ripoff_stack) {
703 	ripoff_t *rop;
704 
705 	for (rop = safe_ripoff_stack;
706 	     rop != safe_ripoff_sp && (rop - safe_ripoff_stack) < N_RIPS;
707 	     rop++) {
708 
709 	    /* If we must simulate soft labels, grab off the line to be used.
710 	       We assume that we must simulate, if it is none of the standard
711 	       formats (4-4 or 3-2-3) for which there may be some hardware
712 	       support. */
713 	    if (rop->hook == _nc_slk_initialize) {
714 		if (!TerminalOf(sp)) {
715 		    continue;
716 		}
717 		if (!(NumLabels <= 0 || !SLK_STDFMT(slk_format))) {
718 		    continue;
719 		}
720 	    }
721 	    if (rop->hook) {
722 		int count;
723 		WINDOW *w;
724 
725 		count = (rop->line < 0) ? -rop->line : rop->line;
726 		T(("ripping off %i lines at %s", count,
727 		   ((rop->line < 0)
728 		    ? "bottom"
729 		    : "top")));
730 
731 		w = NCURSES_SP_NAME(newwin) (NCURSES_SP_ARGx
732 					     count, scolumns,
733 					     ((rop->line < 0)
734 					      ? sp->_lines_avail - count
735 					      : 0),
736 					     0);
737 		if (w) {
738 		    rop->win = w;
739 		    rop->hook(w, scolumns);
740 		} else {
741 		    ReturnScreenError();
742 		}
743 		if (rop->line < 0) {
744 		    bottom_stolen += count;
745 		} else {
746 		    sp->_topstolen = (NCURSES_SIZE_T) (sp->_topstolen + count);
747 		}
748 		sp->_lines_avail = (NCURSES_SIZE_T) (sp->_lines_avail - count);
749 	    }
750 	}
751 	/* reset the stack */
752 	safe_ripoff_sp = safe_ripoff_stack;
753     }
754 
755     T(("creating stdscr"));
756     (void) bottom_stolen;
757     assert((sp->_lines_avail + sp->_topstolen + bottom_stolen) == slines);
758     if ((StdScreen(sp) = NCURSES_SP_NAME(newwin) (NCURSES_SP_ARGx
759 						  sp->_lines_avail,
760 						  scolumns, 0, 0)) == 0) {
761 	ReturnScreenError();
762     }
763     SET_LINES(sp->_lines_avail);
764 #if !USE_REENTRANT
765     stdscr = StdScreen(sp);
766 #endif
767     sp->_prescreen = FALSE;
768     returnCode(OK);
769 }
770 
771 #if NCURSES_SP_FUNCS
772 NCURSES_EXPORT(int)
773 _nc_setupscreen(int slines GCC_UNUSED,
774 		int scolumns GCC_UNUSED,
775 		FILE *output,
776 		int filtered,
777 		int slk_format)
778 {
779     SCREEN *sp = 0;
780     int rc = NCURSES_SP_NAME(_nc_setupscreen) (&sp,
781 					       slines,
782 					       scolumns,
783 					       output,
784 					       filtered,
785 					       slk_format);
786     if (rc != OK)
787 	_nc_set_screen(0);
788     return rc;
789 }
790 #endif
791 
792 /*
793  * The internal implementation interprets line as the number of lines to rip
794  * off from the top or bottom.
795  */
796 NCURSES_EXPORT(int)
797 NCURSES_SP_NAME(_nc_ripoffline) (NCURSES_SP_DCLx
798 				 int line,
799 				 int (*init) (WINDOW *, int))
800 {
801     int code = ERR;
802     TR_FUNC_BFR(1);
803 
804     START_TRACE();
805     T((T_CALLED("ripoffline(%p,%d,%s)"),
806        (void *) SP_PARM, line,
807        TR_FUNC_ARG(0, init)));
808 
809 #if NCURSES_SP_FUNCS
810     if (SP_PARM != 0 && SP_PARM->_prescreen)
811 #endif
812     {
813 	if (line == 0) {
814 	    code = OK;
815 	} else {
816 	    if (safe_ripoff_sp == 0) {
817 		safe_ripoff_sp = safe_ripoff_stack;
818 	    }
819 	    if (safe_ripoff_sp < safe_ripoff_stack + N_RIPS) {
820 		safe_ripoff_sp->line = line;
821 		safe_ripoff_sp->hook = init;
822 		(safe_ripoff_sp)++;
823 		T(("ripped-off %d:%d chunks",
824 		   (int) (safe_ripoff_sp - safe_ripoff_stack), N_RIPS));
825 		code = OK;
826 	    }
827 	}
828     }
829 
830     returnCode(code);
831 }
832 
833 #if NCURSES_SP_FUNCS
834 NCURSES_EXPORT(int)
835 _nc_ripoffline(int line, int (*init) (WINDOW *, int))
836 {
837     int rc;
838 
839     _nc_init_pthreads();
840     _nc_lock_global(prescreen);
841     START_TRACE();
842     rc = NCURSES_SP_NAME(_nc_ripoffline) (CURRENT_SCREEN_PRE, line, init);
843     _nc_unlock_global(prescreen);
844 
845     return rc;
846 }
847 #endif
848 
849 NCURSES_EXPORT(int)
850 NCURSES_SP_NAME(ripoffline) (NCURSES_SP_DCLx
851 			     int line,
852 			     int (*init) (WINDOW *, int))
853 {
854     START_TRACE();
855     return NCURSES_SP_NAME(_nc_ripoffline) (NCURSES_SP_ARGx
856 					    (line < 0) ? -1 : 1,
857 					    init);
858 }
859 
860 #if NCURSES_SP_FUNCS
861 NCURSES_EXPORT(int)
862 ripoffline(int line, int (*init) (WINDOW *, int))
863 {
864     int rc;
865 
866     _nc_init_pthreads();
867     _nc_lock_global(prescreen);
868     START_TRACE();
869     rc = NCURSES_SP_NAME(ripoffline) (CURRENT_SCREEN_PRE, line, init);
870     _nc_unlock_global(prescreen);
871 
872     return rc;
873 }
874 #endif
875