1 /****************************************************************************
2 * Copyright 2019-2021,2022 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 ** lib_addch.c
32 **
33 ** The routine waddch().
34 **
35 */
36
37 #include <curses.priv.h>
38 #include <ctype.h>
39
40 MODULE_ID("$Id: lib_addch.c,v 1.141 2022/06/12 15:16:41 tom Exp $")
41
42 static const NCURSES_CH_T blankchar = NewChar(BLANK_TEXT);
43
44 /*
45 * Ugly microtweaking alert. Everything from here to end of module is
46 * likely to be speed-critical -- profiling data sure says it is!
47 * Most of the important screen-painting functions are shells around
48 * waddch(). So we make every effort to reduce function-call overhead
49 * by inlining stuff, even at the cost of making wrapped copies for
50 * export. Also we supply some internal versions that don't call the
51 * window sync hook, for use by string-put functions.
52 */
53
54 /* Return bit mask for clearing color pair number if given ch has color */
55 #define COLOR_MASK(ch) (~(attr_t)(((ch) & A_COLOR) ? A_COLOR : 0))
56
57 static NCURSES_INLINE NCURSES_CH_T
render_char(WINDOW * win,NCURSES_CH_T ch)58 render_char(WINDOW *win, NCURSES_CH_T ch)
59 /* compute a rendition of the given char correct for the current context */
60 {
61 attr_t a = WINDOW_ATTRS(win);
62 int pair = GetPair(ch);
63
64 if (ISBLANK(ch)
65 && AttrOf(ch) == A_NORMAL
66 && pair == 0) {
67 /* color/pair in attrs has precedence over bkgrnd */
68 ch = win->_nc_bkgd;
69 SetAttr(ch, a | AttrOf(win->_nc_bkgd));
70 if ((pair = GET_WINDOW_PAIR(win)) == 0)
71 pair = GetPair(win->_nc_bkgd);
72 SetPair(ch, pair);
73 } else {
74 /* color in attrs has precedence over bkgrnd */
75 a |= AttrOf(win->_nc_bkgd) & COLOR_MASK(a);
76 /* color in ch has precedence */
77 if (pair == 0) {
78 if ((pair = GET_WINDOW_PAIR(win)) == 0)
79 pair = GetPair(win->_nc_bkgd);
80 }
81 AddAttr(ch, (a & COLOR_MASK(AttrOf(ch))));
82 SetPair(ch, pair);
83 }
84
85 TR(TRACE_VIRTPUT,
86 ("render_char bkg %s (%d), attrs %s (%d) -> ch %s (%d)",
87 _tracech_t2(1, CHREF(win->_nc_bkgd)),
88 GetPair(win->_nc_bkgd),
89 _traceattr(WINDOW_ATTRS(win)),
90 GET_WINDOW_PAIR(win),
91 _tracech_t2(3, CHREF(ch)),
92 GetPair(ch)));
93
94 return (ch);
95 }
96
97 NCURSES_EXPORT(NCURSES_CH_T)
_nc_render(WINDOW * win,NCURSES_CH_T ch)98 _nc_render(WINDOW *win, NCURSES_CH_T ch)
99 /* make render_char() visible while still allowing us to inline it below */
100 {
101 return render_char(win, ch);
102 }
103
104 /* check if position is legal; if not, return error */
105 #ifndef NDEBUG /* treat this like an assertion */
106 #define CHECK_POSITION(win, x, y) \
107 if (y > win->_maxy \
108 || x > win->_maxx \
109 || y < 0 \
110 || x < 0) { \
111 TR(TRACE_VIRTPUT, ("Alert! Win=%p _curx = %d, _cury = %d " \
112 "(_maxx = %d, _maxy = %d)", win, x, y, \
113 win->_maxx, win->_maxy)); \
114 return(ERR); \
115 }
116 #else
117 #define CHECK_POSITION(win, x, y) /* nothing */
118 #endif
119
120 static bool
newline_forces_scroll(WINDOW * win,NCURSES_SIZE_T * ypos)121 newline_forces_scroll(WINDOW *win, NCURSES_SIZE_T *ypos)
122 {
123 bool result = FALSE;
124
125 if (*ypos >= win->_regtop && *ypos <= win->_regbottom) {
126 if (*ypos == win->_regbottom) {
127 *ypos = win->_regbottom;
128 result = TRUE;
129 } else if (*ypos < win->_maxy) {
130 *ypos = (NCURSES_SIZE_T) (*ypos + 1);
131 }
132 } else if (*ypos < win->_maxy) {
133 *ypos = (NCURSES_SIZE_T) (*ypos + 1);
134 }
135 return result;
136 }
137
138 /*
139 * The _WRAPPED flag is useful only for telling an application that we've just
140 * wrapped the cursor. We don't do anything with this flag except set it when
141 * wrapping, and clear it whenever we move the cursor. If we try to wrap at
142 * the lower-right corner of a window, we cannot move the cursor (since that
143 * wouldn't be legal). So we return an error (which is what SVr4 does).
144 * Unlike SVr4, we can successfully add a character to the lower-right corner
145 * (Solaris 2.6 does this also, however).
146 */
147 static int
wrap_to_next_line(WINDOW * win)148 wrap_to_next_line(WINDOW *win)
149 {
150 win->_flags |= _WRAPPED;
151 if (newline_forces_scroll(win, &(win->_cury))) {
152 win->_curx = win->_maxx;
153 if (!win->_scroll)
154 return (ERR);
155 scroll(win);
156 }
157 win->_curx = 0;
158 return (OK);
159 }
160
161 #if USE_WIDEC_SUPPORT
162 static int waddch_literal(WINDOW *, NCURSES_CH_T);
163 /*
164 * Fill the given number of cells with blanks using the current background
165 * rendition. This saves/restores the current x-position.
166 */
167 static void
fill_cells(WINDOW * win,int count)168 fill_cells(WINDOW *win, int count)
169 {
170 NCURSES_CH_T blank = blankchar;
171 int save_x = win->_curx;
172 int save_y = win->_cury;
173
174 while (count-- > 0) {
175 if (waddch_literal(win, blank) == ERR)
176 break;
177 }
178 win->_curx = (NCURSES_SIZE_T) save_x;
179 win->_cury = (NCURSES_SIZE_T) save_y;
180 }
181 #endif
182
183 /*
184 * Build up the bytes for a multibyte character, returning the length when
185 * complete (a positive number), -1 for error and -2 for incomplete.
186 */
187 #if USE_WIDEC_SUPPORT
188 NCURSES_EXPORT(int)
_nc_build_wch(WINDOW * win,ARG_CH_T ch)189 _nc_build_wch(WINDOW *win, ARG_CH_T ch)
190 {
191 char *buffer = WINDOW_EXT(win, addch_work);
192 int len;
193 int x = win->_curx;
194 int y = win->_cury;
195 mbstate_t state;
196 wchar_t result;
197
198 if ((WINDOW_EXT(win, addch_used) != 0) &&
199 (WINDOW_EXT(win, addch_x) != x ||
200 WINDOW_EXT(win, addch_y) != y)) {
201 /* discard the incomplete multibyte character */
202 WINDOW_EXT(win, addch_used) = 0;
203 TR(TRACE_VIRTPUT,
204 ("Alert discarded multibyte on move (%d,%d) -> (%d,%d)",
205 WINDOW_EXT(win, addch_y), WINDOW_EXT(win, addch_x),
206 y, x));
207 }
208 WINDOW_EXT(win, addch_x) = x;
209 WINDOW_EXT(win, addch_y) = y;
210
211 /*
212 * If the background character is a wide-character, that may interfere with
213 * processing multibyte characters in this function.
214 */
215 if (!is8bits(CharOf(CHDEREF(ch)))) {
216 if (WINDOW_EXT(win, addch_used) != 0) {
217 /* discard the incomplete multibyte character */
218 WINDOW_EXT(win, addch_used) = 0;
219 TR(TRACE_VIRTPUT,
220 ("Alert discarded incomplete multibyte"));
221 }
222 return 1;
223 }
224
225 init_mb(state);
226 buffer[WINDOW_EXT(win, addch_used)] = (char) CharOf(CHDEREF(ch));
227 WINDOW_EXT(win, addch_used) += 1;
228 buffer[WINDOW_EXT(win, addch_used)] = '\0';
229 if ((len = (int) mbrtowc(&result,
230 buffer,
231 (size_t) WINDOW_EXT(win, addch_used),
232 &state)) > 0) {
233 attr_t attrs = AttrOf(CHDEREF(ch));
234 if_EXT_COLORS(int pair = GetPair(CHDEREF(ch)));
235 SetChar(CHDEREF(ch), result, attrs);
236 if_EXT_COLORS(SetPair(CHDEREF(ch), pair));
237 WINDOW_EXT(win, addch_used) = 0;
238 } else if (len == -1) {
239 /*
240 * An error occurred. We could either discard everything,
241 * or assume that the error was in the previous input.
242 * Try the latter.
243 */
244 TR(TRACE_VIRTPUT, ("Alert! mbrtowc returns error"));
245 /* handle this with unctrl() */
246 WINDOW_EXT(win, addch_used) = 0;
247 }
248 return len;
249 }
250 #endif /* USE_WIDEC_SUPPORT */
251
252 static
253 #if !USE_WIDEC_SUPPORT /* cannot be inline if it is recursive */
254 NCURSES_INLINE
255 #endif
256 int
waddch_literal(WINDOW * win,NCURSES_CH_T ch)257 waddch_literal(WINDOW *win, NCURSES_CH_T ch)
258 {
259 int x;
260 int y;
261 struct ldat *line;
262
263 x = win->_curx;
264 y = win->_cury;
265
266 CHECK_POSITION(win, x, y);
267
268 ch = render_char(win, ch);
269
270 line = win->_line + y;
271
272 CHANGED_CELL(line, x);
273
274 /*
275 * Build up multibyte characters until we have a wide-character.
276 */
277 #if NCURSES_SP_FUNCS
278 #define DeriveSP() SCREEN *sp = _nc_screen_of(win);
279 #else
280 #define DeriveSP() /*nothing */
281 #endif
282 if_WIDEC({
283 DeriveSP();
284 if (WINDOW_EXT(win, addch_used) != 0 || !Charable(ch)) {
285 int len = _nc_build_wch(win, CHREF(ch));
286
287 if (len >= -1) {
288 attr_t attr = AttrOf(ch);
289
290 /* handle EILSEQ (i.e., when len >= -1) */
291 if (len == -1 && is8bits(CharOf(ch))) {
292 const char *s = NCURSES_SP_NAME(unctrl)
293 (NCURSES_SP_ARGx (chtype) CharOf(ch));
294
295 if (s[1] != '\0') {
296 int rc = OK;
297 while (*s != '\0') {
298 rc = waddch(win, UChar(*s) | attr);
299 if (rc != OK)
300 break;
301 ++s;
302 }
303 return rc;
304 }
305 }
306 if (len == -1)
307 return waddch(win, ' ' | attr);
308 } else {
309 return OK;
310 }
311 }
312 });
313
314 /*
315 * Non-spacing characters are added to the current cell.
316 *
317 * Spacing characters that are wider than one column require some display
318 * adjustments.
319 */
320 if_WIDEC({
321 int len = _nc_wacs_width(CharOf(ch));
322 int i;
323 int j;
324
325 if (len == 0) { /* non-spacing */
326 if ((x > 0 && y >= 0)
327 || (win->_maxx >= 0 && win->_cury >= 1)) {
328 NCURSES_CH_T *dst;
329 wchar_t *chars;
330 if (x > 0 && y >= 0) {
331 for (j = x - 1; j >= 0; --j) {
332 if (!isWidecExt(win->_line[y].text[j])) {
333 win->_curx = (NCURSES_SIZE_T) j;
334 break;
335 }
336 }
337 dst = &(win->_line[y].text[j]);
338 } else {
339 dst = &(win->_line[y - 1].text[win->_maxx]);
340 }
341 chars = dst->chars;
342 for (i = 0; i < CCHARW_MAX; ++i) {
343 if (chars[i] == 0) {
344 TR(TRACE_VIRTPUT,
345 ("adding non-spacing %s (level %d)",
346 _tracech_t(CHREF(ch)), i));
347 chars[i] = CharOf(ch);
348 break;
349 }
350 }
351 }
352 goto testwrapping;
353 } else if (len > 1) { /* multi-column characters */
354 /*
355 * Check if the character will fit on the current line. If it does
356 * not fit, fill in the remainder of the line with blanks. and
357 * move to the next line.
358 */
359 if (len > win->_maxx + 1) {
360 TR(TRACE_VIRTPUT, ("character will not fit"));
361 return ERR;
362 } else if (x + len > win->_maxx + 1) {
363 int count = win->_maxx + 1 - x;
364 TR(TRACE_VIRTPUT, ("fill %d remaining cells", count));
365 fill_cells(win, count);
366 if (wrap_to_next_line(win) == ERR)
367 return ERR;
368 x = win->_curx;
369 y = win->_cury;
370 CHECK_POSITION(win, x, y);
371 line = win->_line + y;
372 }
373 /*
374 * Check for cells which are orphaned by adding this character, set
375 * those to blanks.
376 *
377 * FIXME: this actually could fill j-i cells, more complicated to
378 * setup though.
379 */
380 for (i = 0; i < len; ++i) {
381 if (isWidecBase(win->_line[y].text[x + i])) {
382 break;
383 } else if (isWidecExt(win->_line[y].text[x + i])) {
384 for (j = i; x + j <= win->_maxx; ++j) {
385 if (!isWidecExt(win->_line[y].text[x + j])) {
386 TR(TRACE_VIRTPUT, ("fill %d orphan cells", j));
387 fill_cells(win, j);
388 break;
389 }
390 }
391 break;
392 }
393 }
394 /*
395 * Finally, add the cells for this character.
396 */
397 for (i = 0; i < len; ++i) {
398 NCURSES_CH_T value = ch;
399 SetWidecExt(value, i);
400 TR(TRACE_VIRTPUT, ("multicolumn %d:%d (%d,%d)",
401 i + 1, len,
402 win->_begy + y, win->_begx + x));
403 line->text[x] = value;
404 CHANGED_CELL(line, x);
405 ++x;
406 }
407 goto testwrapping;
408 }
409 });
410
411 /*
412 * Single-column characters.
413 */
414 line->text[x++] = ch;
415 /*
416 * This label is used only for wide-characters.
417 */
418 if_WIDEC(
419 testwrapping:
420 );
421
422 TR(TRACE_VIRTPUT, ("cell (%d, %d..%d) = %s",
423 win->_cury, win->_curx, x - 1,
424 _tracech_t(CHREF(line->text[win->_curx]))));
425
426 if (x > win->_maxx) {
427 return wrap_to_next_line(win);
428 }
429 win->_curx = (NCURSES_SIZE_T) x;
430 return OK;
431 }
432
433 static NCURSES_INLINE int
waddch_nosync(WINDOW * win,const NCURSES_CH_T ch)434 waddch_nosync(WINDOW *win, const NCURSES_CH_T ch)
435 /* the workhorse function -- add a character to the given window */
436 {
437 NCURSES_SIZE_T x, y;
438 chtype t = (chtype) CharOf(ch);
439 #if USE_WIDEC_SUPPORT || NCURSES_SP_FUNCS || USE_REENTRANT
440 SCREEN *sp = _nc_screen_of(win);
441 #endif
442 const char *s = NCURSES_SP_NAME(unctrl) (NCURSES_SP_ARGx t);
443 int tabsize = 8;
444
445 /*
446 * If we are using the alternate character set, forget about locale.
447 * Otherwise, if unctrl() returns a single-character or the locale
448 * claims the code is printable (and not also a control character),
449 * treat it that way.
450 */
451 if ((AttrOf(ch) & A_ALTCHARSET)
452 || (
453 #if USE_WIDEC_SUPPORT
454 (sp != 0 && sp->_legacy_coding) &&
455 #endif
456 s[1] == 0
457 )
458 || (
459 (isprint((int) t) && !iscntrl((int) t))
460 #if USE_WIDEC_SUPPORT
461 || ((sp == 0 || !sp->_legacy_coding) &&
462 (WINDOW_EXT(win, addch_used)
463 || !_nc_is_charable(CharOf(ch))))
464 #endif
465 )) {
466 return waddch_literal(win, ch);
467 }
468
469 /*
470 * Handle carriage control and other codes that are not printable, or are
471 * known to expand to more than one character according to unctrl().
472 */
473 x = win->_curx;
474 y = win->_cury;
475 CHECK_POSITION(win, x, y);
476
477 switch (t) {
478 case '\t':
479 #if USE_REENTRANT
480 tabsize = *ptrTabsize(sp);
481 #else
482 tabsize = TABSIZE;
483 #endif
484 x = (NCURSES_SIZE_T) (x + (tabsize - (x % tabsize)));
485 /*
486 * Space-fill the tab on the bottom line so that we'll get the
487 * "correct" cursor position.
488 */
489 if ((!win->_scroll && (y == win->_regbottom))
490 || (x <= win->_maxx)) {
491 NCURSES_CH_T blank = blankchar;
492 AddAttr(blank, AttrOf(ch));
493 while (win->_curx < x) {
494 if (waddch_literal(win, blank) == ERR)
495 return (ERR);
496 }
497 break;
498 } else {
499 wclrtoeol(win);
500 win->_flags |= _WRAPPED;
501 if (newline_forces_scroll(win, &y)) {
502 x = win->_maxx;
503 if (win->_scroll) {
504 scroll(win);
505 x = 0;
506 }
507 } else {
508 x = 0;
509 }
510 }
511 break;
512 case '\n':
513 wclrtoeol(win);
514 if (newline_forces_scroll(win, &y)) {
515 if (win->_scroll)
516 scroll(win);
517 else
518 return (ERR);
519 }
520 /* FALLTHRU */
521 case '\r':
522 x = 0;
523 win->_flags &= ~_WRAPPED;
524 break;
525 case '\b':
526 if (x == 0)
527 return (OK);
528 x--;
529 win->_flags &= ~_WRAPPED;
530 break;
531 default:
532 while (*s) {
533 NCURSES_CH_T sch;
534 SetChar(sch, UChar(*s++), AttrOf(ch));
535 if_EXT_COLORS(SetPair(sch, GetPair(ch)));
536 if (waddch_literal(win, sch) == ERR)
537 return ERR;
538 }
539 return (OK);
540 }
541
542 win->_curx = x;
543 win->_cury = y;
544
545 return (OK);
546 }
547
548 NCURSES_EXPORT(int)
_nc_waddch_nosync(WINDOW * win,const NCURSES_CH_T c)549 _nc_waddch_nosync(WINDOW *win, const NCURSES_CH_T c)
550 /* export copy of waddch_nosync() so the string-put functions can use it */
551 {
552 return (waddch_nosync(win, c));
553 }
554
555 /*
556 * The versions below call _nc_synchook(). We wanted to avoid this in the
557 * version exported for string puts; they'll call _nc_synchook once at end
558 * of run.
559 */
560
561 /* These are actual entry points */
562
563 NCURSES_EXPORT(int)
waddch(WINDOW * win,const chtype ch)564 waddch(WINDOW *win, const chtype ch)
565 {
566 int code = ERR;
567 NCURSES_CH_T wch;
568 SetChar2(wch, ch);
569
570 TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_CALLED("waddch(%p, %s)"), (void *) win,
571 _tracechtype(ch)));
572
573 if (win && (waddch_nosync(win, wch) != ERR)) {
574 _nc_synchook(win);
575 code = OK;
576 }
577
578 TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_RETURN("%d"), code));
579 return (code);
580 }
581
582 NCURSES_EXPORT(int)
wechochar(WINDOW * win,const chtype ch)583 wechochar(WINDOW *win, const chtype ch)
584 {
585 int code = ERR;
586 NCURSES_CH_T wch;
587 SetChar2(wch, ch);
588
589 TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_CALLED("wechochar(%p, %s)"),
590 (void *) win,
591 _tracechtype(ch)));
592
593 if (win && (waddch_nosync(win, wch) != ERR)) {
594 bool save_immed = win->_immed;
595 win->_immed = TRUE;
596 _nc_synchook(win);
597 win->_immed = save_immed;
598 code = OK;
599 }
600 TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_RETURN("%d"), code));
601 return (code);
602 }
603