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 
37 /*
38 **	lib_data.c
39 **
40 **	Common data that may/may not be allocated, but is referenced globally
41 **
42 */
43 
44 #include <curses.priv.h>
45 
46 MODULE_ID("$Id: lib_data.c,v 1.80 2020/02/02 23:34:34 tom Exp $")
47 
48 /*
49  * OS/2's native linker complains if we don't initialize public data when
50  * constructing a dll (reported by J.J.G.Ripoll).
51  */
52 #if USE_REENTRANT
53 NCURSES_EXPORT(WINDOW *)
54 NCURSES_PUBLIC_VAR(stdscr) (void)
55 {
56     return CURRENT_SCREEN ? StdScreen(CURRENT_SCREEN) : 0;
57 }
58 NCURSES_EXPORT(WINDOW *)
59 NCURSES_PUBLIC_VAR(curscr) (void)
60 {
61     return CURRENT_SCREEN ? CurScreen(CURRENT_SCREEN) : 0;
62 }
63 NCURSES_EXPORT(WINDOW *)
64 NCURSES_PUBLIC_VAR(newscr) (void)
65 {
66     return CURRENT_SCREEN ? NewScreen(CURRENT_SCREEN) : 0;
67 }
68 #else
69 NCURSES_EXPORT_VAR(WINDOW *) stdscr = 0;
70 NCURSES_EXPORT_VAR(WINDOW *) curscr = 0;
71 NCURSES_EXPORT_VAR(WINDOW *) newscr = 0;
72 #endif
73 
74 NCURSES_EXPORT_VAR(SCREEN *) _nc_screen_chain = 0;
75 
76 /*
77  * The variable 'SP' will be defined as a function on systems that cannot link
78  * data-only modules, since it is used in a lot of places within ncurses and we
79  * cannot guarantee that any application will use any particular function.  We
80  * put the WINDOW variables in this module, because it appears that any
81  * application that uses them will also use 'SP'.
82  *
83  * This module intentionally does not reference other ncurses modules, to avoid
84  * module coupling that increases the size of the executable.
85  */
86 #if BROKEN_LINKER
87 static SCREEN *my_screen;
88 
89 NCURSES_EXPORT(SCREEN *)
90 _nc_screen(void)
91 {
92     return my_screen;
93 }
94 
95 NCURSES_EXPORT(int)
96 _nc_alloc_screen(void)
97 {
98     my_screen = _nc_alloc_screen_sp();
99     T(("_nc_alloc_screen_sp %p", my_screen));
100     return (my_screen != 0);
101 }
102 
103 NCURSES_EXPORT(void)
104 _nc_set_screen(SCREEN *sp)
105 {
106     my_screen = sp;
107 }
108 
109 #else
110 
111 NCURSES_EXPORT_VAR(SCREEN *) SP = NULL; /* Some linkers require initialized data... */
112 #endif
113 /* *INDENT-OFF* */
114 #define CHARS_0s { '\0' }
115 
116 #define TGETENT_0 { 0L, FALSE, NULL, NULL, NULL }
117 #define TGETENT_0s { TGETENT_0, TGETENT_0, TGETENT_0, TGETENT_0 }
118 
119 NCURSES_EXPORT_VAR(NCURSES_GLOBALS) _nc_globals = {
120     0,				/* have_sigtstp */
121     0,				/* have_sigwinch */
122     0,				/* cleanup_nested */
123 
124     FALSE,			/* init_signals */
125     FALSE,			/* init_screen */
126 
127     NULL,			/* comp_sourcename */
128     NULL,			/* comp_termtype */
129 
130     FALSE,			/* have_tic_directory */
131     FALSE,			/* keep_tic_directory */
132     0,				/* tic_directory */
133 
134     NULL,			/* dbi_list */
135     0,				/* dbi_size */
136 
137     NULL,			/* first_name */
138     NULL,			/* keyname_table */
139     0,				/* init_keyname */
140 
141     0,				/* slk_format */
142 
143     2048,			/* getstr_limit */
144 
145     NULL,			/* safeprint_buf */
146     0,				/* safeprint_used */
147 
148     TGETENT_0s,			/* tgetent_cache */
149     0,				/* tgetent_index */
150     0,				/* tgetent_sequence */
151 
152     0,				/* dbd_blob */
153     0,				/* dbd_list */
154     0,				/* dbd_size */
155     0,				/* dbd_time */
156     { { 0, 0 } },		/* dbd_vars */
157 
158 #ifdef USE_TERM_DRIVER
159     0,				/* term_driver */
160 #endif
161 
162 #ifndef USE_SP_WINDOWLIST
163     0,				/* _nc_windowlist */
164 #endif
165 
166 #if USE_HOME_TERMINFO
167     NULL,			/* home_terminfo */
168 #endif
169 
170 #if !USE_SAFE_SPRINTF
171     0,				/* safeprint_cols */
172     0,				/* safeprint_rows */
173 #endif
174 
175 #ifdef USE_PTHREADS
176     PTHREAD_MUTEX_INITIALIZER,	/* mutex_curses */
177     PTHREAD_MUTEX_INITIALIZER,	/* mutex_prescreen */
178     PTHREAD_MUTEX_INITIALIZER,	/* mutex_screen */
179     PTHREAD_MUTEX_INITIALIZER,	/* mutex_update */
180     PTHREAD_MUTEX_INITIALIZER,	/* mutex_tst_tracef */
181     PTHREAD_MUTEX_INITIALIZER,	/* mutex_tracef */
182     0,				/* nested_tracef */
183     0,				/* use_pthreads */
184 #if USE_PTHREADS_EINTR
185     0,				/* read_thread */
186 #endif
187 #endif
188 #if USE_WIDEC_SUPPORT
189     CHARS_0s,			/* key_name */
190 #endif
191 #ifdef TRACE
192     FALSE,			/* trace_opened */
193     CHARS_0s,			/* trace_fname */
194     0,				/* trace_level */
195     NULL,			/* trace_fp */
196     -1,				/* trace_fd */
197 
198     NULL,			/* tracearg_buf */
199     0,				/* tracearg_used */
200 
201     NULL,			/* tracebuf_ptr */
202     0,				/* tracebuf_used */
203 
204     CHARS_0s,			/* tracechr_buf */
205 
206     NULL,			/* tracedmp_buf */
207     0,				/* tracedmp_used */
208 
209     NULL,			/* tracetry_buf */
210     0,				/* tracetry_used */
211 
212     { CHARS_0s, CHARS_0s },	/* traceatr_color_buf */
213     0,				/* traceatr_color_sel */
214     -1,				/* traceatr_color_last */
215 #if !defined(USE_PTHREADS) && USE_REENTRANT
216     0,				/* nested_tracef */
217 #endif
218 #endif /* TRACE */
219 #if NO_LEAKS
220     FALSE,			/* leak_checking */
221 #endif
222 };
223 
224 #define STACK_FRAME_0	{ { 0 }, 0 }
225 #define STACK_FRAME_0s	{ STACK_FRAME_0 }
226 #define NUM_VARS_0s	{ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }
227 
228 #define RIPOFF_0	{ 0,0,0 }
229 #define RIPOFF_0s	{ RIPOFF_0 }
230 
231 NCURSES_EXPORT_VAR(NCURSES_PRESCREEN) _nc_prescreen = {
232     NULL,			/* allocated */
233     TRUE,			/* use_env */
234     FALSE,			/* filter_mode */
235     A_NORMAL,			/* previous_attr */
236     {				/* tparm_state */
237 	NULL,			/* tparam_base */
238 
239 	STACK_FRAME_0s,		/* stack */
240 	0,			/* stack_ptr */
241 
242 	NULL,			/* out_buff */
243 	0,			/* out_size */
244 	0,			/* out_used */
245 
246 	NULL,			/* fmt_buff */
247 	0,			/* fmt_size */
248 
249 	NUM_VARS_0s,		/* dynamic_var */
250 	NUM_VARS_0s,		/* static_vars */
251 #ifdef TRACE
252 	NULL,			/* tname */
253 #endif
254     },
255     NULL,			/* saved_tty */
256     FALSE,			/* use_tioctl */
257     0,				/* _outch */
258 #ifndef USE_SP_RIPOFF
259     RIPOFF_0s,			/* ripoff */
260     NULL,			/* rsp */
261 #endif
262 #if NCURSES_NO_PADDING
263     FALSE,			/* flag to set if padding disabled  */
264 #endif
265 #if BROKEN_LINKER || USE_REENTRANT
266     NULL,			/* real_acs_map */
267     0,				/* LINES */
268     0,				/* COLS */
269     8,				/* TABSIZE */
270     1000,			/* ESCDELAY */
271     0,				/* cur_term */
272 #endif
273 #ifdef TRACE
274 #if BROKEN_LINKER || USE_REENTRANT
275     0L,				/* _outchars */
276     NULL,			/* _tputs_trace */
277 #endif
278 #endif
279 };
280 /* *INDENT-ON* */
281 
282 /*
283  * wgetch() and other functions with a WINDOW* parameter may use a SCREEN*
284  * internally, and it is useful to allow those to be invoked without switching
285  * SCREEN's, e.g., for multi-threaded applications.
286  */
287 NCURSES_EXPORT(SCREEN *)
288 _nc_screen_of(WINDOW *win)
289 {
290     SCREEN *sp = 0;
291 
292     if (win != 0) {
293 	sp = WINDOW_EXT(win, screen);
294     }
295     return (sp);
296 }
297 
298 /******************************************************************************/
299 #ifdef USE_PTHREADS
300 static void
301 init_global_mutexes(void)
302 {
303     static bool initialized = FALSE;
304 
305     if (!initialized) {
306 	initialized = TRUE;
307 	_nc_mutex_init(&_nc_globals.mutex_curses);
308 	_nc_mutex_init(&_nc_globals.mutex_prescreen);
309 	_nc_mutex_init(&_nc_globals.mutex_screen);
310 	_nc_mutex_init(&_nc_globals.mutex_update);
311 	_nc_mutex_init(&_nc_globals.mutex_tst_tracef);
312 	_nc_mutex_init(&_nc_globals.mutex_tracef);
313     }
314 }
315 
316 NCURSES_EXPORT(void)
317 _nc_init_pthreads(void)
318 {
319     if (_nc_use_pthreads)
320 	return;
321 # if USE_WEAK_SYMBOLS
322     if ((pthread_mutex_init) == 0)
323 	return;
324     if ((pthread_mutex_lock) == 0)
325 	return;
326     if ((pthread_mutex_unlock) == 0)
327 	return;
328     if ((pthread_mutex_trylock) == 0)
329 	return;
330     if ((pthread_mutexattr_settype) == 0)
331 	return;
332 # endif
333     _nc_use_pthreads = 1;
334     init_global_mutexes();
335 }
336 
337 /*
338  * Use recursive mutexes if we have them - they're part of Unix98.
339  * For the cases where we do not, _nc_mutex_trylock() is used to avoid a
340  * deadlock, at the expense of memory leaks and unexpected failures that
341  * may not be handled by typical clients.
342  *
343  * FIXME - need configure check for PTHREAD_MUTEX_RECURSIVE, define it to
344  * PTHREAD_MUTEX_NORMAL if not supported.
345  */
346 NCURSES_EXPORT(void)
347 _nc_mutex_init(pthread_mutex_t * obj)
348 {
349     pthread_mutexattr_t recattr;
350 
351     if (_nc_use_pthreads) {
352 	pthread_mutexattr_init(&recattr);
353 	pthread_mutexattr_settype(&recattr, PTHREAD_MUTEX_RECURSIVE);
354 	pthread_mutex_init(obj, &recattr);
355     }
356 }
357 
358 NCURSES_EXPORT(int)
359 _nc_mutex_lock(pthread_mutex_t * obj)
360 {
361     if (_nc_use_pthreads == 0)
362 	return 0;
363     return pthread_mutex_lock(obj);
364 }
365 
366 NCURSES_EXPORT(int)
367 _nc_mutex_trylock(pthread_mutex_t * obj)
368 {
369     if (_nc_use_pthreads == 0)
370 	return 0;
371     return pthread_mutex_trylock(obj);
372 }
373 
374 NCURSES_EXPORT(int)
375 _nc_mutex_unlock(pthread_mutex_t * obj)
376 {
377     if (_nc_use_pthreads == 0)
378 	return 0;
379     return pthread_mutex_unlock(obj);
380 }
381 #endif /* USE_PTHREADS */
382 
383 #if defined(USE_PTHREADS) || USE_PTHREADS_EINTR
384 #if USE_WEAK_SYMBOLS
385 /*
386  * NB: sigprocmask(2) is global but pthread_sigmask(3p)
387  * only for the calling thread.
388  */
389 NCURSES_EXPORT(int)
390 _nc_sigprocmask(int how, const sigset_t * newmask, sigset_t * oldmask)
391 {
392     if ((pthread_sigmask))
393 	return pthread_sigmask(how, newmask, oldmask);
394     else
395 	return (sigprocmask) (how, newmask, oldmask);
396 }
397 #endif
398 #endif /* USE_PTHREADS */
399