lib_addch.c revision 4e7f425fc9957becb7f3db56f0d7be9455d0c54f
1/****************************************************************************
2 * Copyright 2019,2020 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**	lib_addch.c
32**
33**	The routine waddch().
34**
35*/
36
37#include <curses.priv.h>
38#include <ctype.h>
39
40MODULE_ID("$Id: lib_addch.c,v 1.134 2020/02/02 23:34:34 tom Exp $")
41
42static 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
57static NCURSES_INLINE NCURSES_CH_T
58render_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
97NCURSES_EXPORT(NCURSES_CH_T)
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
120static bool
121newline_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 */
147static int
148wrap_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
162static 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 */
167static void
168fill_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
188NCURSES_EXPORT(int)
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    init_mb(state);
212    buffer[WINDOW_EXT(win, addch_used)] = (char) CharOf(CHDEREF(ch));
213    WINDOW_EXT(win, addch_used) += 1;
214    buffer[WINDOW_EXT(win, addch_used)] = '\0';
215    if ((len = (int) mbrtowc(&result,
216			     buffer,
217			     (size_t) WINDOW_EXT(win, addch_used),
218			     &state)) > 0) {
219	attr_t attrs = AttrOf(CHDEREF(ch));
220	if_EXT_COLORS(int pair = GetPair(CHDEREF(ch)));
221	SetChar(CHDEREF(ch), result, attrs);
222	if_EXT_COLORS(SetPair(CHDEREF(ch), pair));
223	WINDOW_EXT(win, addch_used) = 0;
224    } else if (len == -1) {
225	/*
226	 * An error occurred.  We could either discard everything,
227	 * or assume that the error was in the previous input.
228	 * Try the latter.
229	 */
230	TR(TRACE_VIRTPUT, ("Alert! mbrtowc returns error"));
231	/* handle this with unctrl() */
232	WINDOW_EXT(win, addch_used) = 0;
233    }
234    return len;
235}
236#endif /* USE_WIDEC_SUPPORT */
237
238static
239#if !USE_WIDEC_SUPPORT		/* cannot be inline if it is recursive */
240NCURSES_INLINE
241#endif
242int
243waddch_literal(WINDOW *win, NCURSES_CH_T ch)
244{
245    int x;
246    int y;
247    struct ldat *line;
248
249    x = win->_curx;
250    y = win->_cury;
251
252    CHECK_POSITION(win, x, y);
253
254    ch = render_char(win, ch);
255
256    line = win->_line + y;
257
258    CHANGED_CELL(line, x);
259
260    /*
261     * Build up multibyte characters until we have a wide-character.
262     */
263#if NCURSES_SP_FUNCS
264#define DeriveSP() SCREEN *sp = _nc_screen_of(win);
265#else
266#define DeriveSP()		/*nothing */
267#endif
268    if_WIDEC({
269	DeriveSP();
270	if (WINDOW_EXT(win, addch_used) != 0 || !Charable(ch)) {
271	    int len = _nc_build_wch(win, CHREF(ch));
272
273	    if (len >= -1) {
274		attr_t attr = AttrOf(ch);
275
276		/* handle EILSEQ (i.e., when len >= -1) */
277		if (len == -1 && is8bits(CharOf(ch))) {
278		    const char *s = NCURSES_SP_NAME(unctrl)
279		      (NCURSES_SP_ARGx (chtype) CharOf(ch));
280
281		    if (s[1] != '\0') {
282			int rc = OK;
283			while (*s != '\0') {
284			    rc = waddch(win, UChar(*s) | attr);
285			    if (rc != OK)
286				break;
287			    ++s;
288			}
289			return rc;
290		    }
291		}
292		if (len == -1)
293		    return waddch(win, ' ' | attr);
294	    } else {
295		return OK;
296	    }
297	}
298    });
299
300    /*
301     * Non-spacing characters are added to the current cell.
302     *
303     * Spacing characters that are wider than one column require some display
304     * adjustments.
305     */
306    if_WIDEC({
307	int len = _nc_wacs_width(CharOf(ch));
308	int i;
309	int j;
310	wchar_t *chars;
311
312	if (len == 0) {		/* non-spacing */
313	    if ((x > 0 && y >= 0)
314		|| (win->_maxx >= 0 && win->_cury >= 1)) {
315		if (x > 0 && y >= 0)
316		    chars = (win->_line[y].text[x - 1].chars);
317		else
318		    chars = (win->_line[y - 1].text[win->_maxx].chars);
319		for (i = 0; i < CCHARW_MAX; ++i) {
320		    if (chars[i] == 0) {
321			TR(TRACE_VIRTPUT,
322			   ("added non-spacing %d: %x",
323			    x, (int) CharOf(ch)));
324			chars[i] = CharOf(ch);
325			break;
326		    }
327		}
328	    }
329	    goto testwrapping;
330	} else if (len > 1) {	/* multi-column characters */
331	    /*
332	     * Check if the character will fit on the current line.  If it does
333	     * not fit, fill in the remainder of the line with blanks.  and
334	     * move to the next line.
335	     */
336	    if (len > win->_maxx + 1) {
337		TR(TRACE_VIRTPUT, ("character will not fit"));
338		return ERR;
339	    } else if (x + len > win->_maxx + 1) {
340		int count = win->_maxx + 1 - x;
341		TR(TRACE_VIRTPUT, ("fill %d remaining cells", count));
342		fill_cells(win, count);
343		if (wrap_to_next_line(win) == ERR)
344		    return ERR;
345		x = win->_curx;
346		y = win->_cury;
347		CHECK_POSITION(win, x, y);
348		line = win->_line + y;
349	    }
350	    /*
351	     * Check for cells which are orphaned by adding this character, set
352	     * those to blanks.
353	     *
354	     * FIXME: this actually could fill j-i cells, more complicated to
355	     * setup though.
356	     */
357	    for (i = 0; i < len; ++i) {
358		if (isWidecBase(win->_line[y].text[x + i])) {
359		    break;
360		} else if (isWidecExt(win->_line[y].text[x + i])) {
361		    for (j = i; x + j <= win->_maxx; ++j) {
362			if (!isWidecExt(win->_line[y].text[x + j])) {
363			    TR(TRACE_VIRTPUT, ("fill %d orphan cells", j));
364			    fill_cells(win, j);
365			    break;
366			}
367		    }
368		    break;
369		}
370	    }
371	    /*
372	     * Finally, add the cells for this character.
373	     */
374	    for (i = 0; i < len; ++i) {
375		NCURSES_CH_T value = ch;
376		SetWidecExt(value, i);
377		TR(TRACE_VIRTPUT, ("multicolumn %d:%d (%d,%d)",
378				   i + 1, len,
379				   win->_begy + y, win->_begx + x));
380		line->text[x] = value;
381		CHANGED_CELL(line, x);
382		++x;
383	    }
384	    goto testwrapping;
385	}
386    });
387
388    /*
389     * Single-column characters.
390     */
391    line->text[x++] = ch;
392    /*
393     * This label is used only for wide-characters.
394     */
395    if_WIDEC(
396  testwrapping:
397    );
398
399    TR(TRACE_VIRTPUT, ("cell (%ld, %ld..%d) = %s",
400		       (long) win->_cury, (long) win->_curx, x - 1,
401		       _tracech_t(CHREF(ch))));
402
403    if (x > win->_maxx) {
404	return wrap_to_next_line(win);
405    }
406    win->_curx = (NCURSES_SIZE_T) x;
407    return OK;
408}
409
410static NCURSES_INLINE int
411waddch_nosync(WINDOW *win, const NCURSES_CH_T ch)
412/* the workhorse function -- add a character to the given window */
413{
414    NCURSES_SIZE_T x, y;
415    chtype t = (chtype) CharOf(ch);
416#if USE_WIDEC_SUPPORT || NCURSES_SP_FUNCS || USE_REENTRANT
417    SCREEN *sp = _nc_screen_of(win);
418#endif
419    const char *s = NCURSES_SP_NAME(unctrl) (NCURSES_SP_ARGx t);
420    int tabsize = 8;
421
422    /*
423     * If we are using the alternate character set, forget about locale.
424     * Otherwise, if unctrl() returns a single-character or the locale
425     * claims the code is printable (and not also a control character),
426     * treat it that way.
427     */
428    if ((AttrOf(ch) & A_ALTCHARSET)
429	|| (
430#if USE_WIDEC_SUPPORT
431	       (sp != 0 && sp->_legacy_coding) &&
432#endif
433	       s[1] == 0
434	)
435	|| (
436	       (isprint((int) t) && !iscntrl((int) t))
437#if USE_WIDEC_SUPPORT
438	       || ((sp == 0 || !sp->_legacy_coding) &&
439		   (WINDOW_EXT(win, addch_used)
440		    || !_nc_is_charable(CharOf(ch))))
441#endif
442	)) {
443	return waddch_literal(win, ch);
444    }
445
446    /*
447     * Handle carriage control and other codes that are not printable, or are
448     * known to expand to more than one character according to unctrl().
449     */
450    x = win->_curx;
451    y = win->_cury;
452    CHECK_POSITION(win, x, y);
453
454    switch (t) {
455    case '\t':
456#if USE_REENTRANT
457	tabsize = *ptrTabsize(sp);
458#else
459	tabsize = TABSIZE;
460#endif
461	x = (NCURSES_SIZE_T) (x + (tabsize - (x % tabsize)));
462	/*
463	 * Space-fill the tab on the bottom line so that we'll get the
464	 * "correct" cursor position.
465	 */
466	if ((!win->_scroll && (y == win->_regbottom))
467	    || (x <= win->_maxx)) {
468	    NCURSES_CH_T blank = blankchar;
469	    AddAttr(blank, AttrOf(ch));
470	    while (win->_curx < x) {
471		if (waddch_literal(win, blank) == ERR)
472		    return (ERR);
473	    }
474	    break;
475	} else {
476	    wclrtoeol(win);
477	    win->_flags |= _WRAPPED;
478	    if (newline_forces_scroll(win, &y)) {
479		x = win->_maxx;
480		if (win->_scroll) {
481		    scroll(win);
482		    x = 0;
483		}
484	    } else {
485		x = 0;
486	    }
487	}
488	break;
489    case '\n':
490	wclrtoeol(win);
491	if (newline_forces_scroll(win, &y)) {
492	    if (win->_scroll)
493		scroll(win);
494	    else
495		return (ERR);
496	}
497	/* FALLTHRU */
498    case '\r':
499	x = 0;
500	win->_flags &= ~_WRAPPED;
501	break;
502    case '\b':
503	if (x == 0)
504	    return (OK);
505	x--;
506	win->_flags &= ~_WRAPPED;
507	break;
508    default:
509	while (*s) {
510	    NCURSES_CH_T sch;
511	    SetChar(sch, UChar(*s++), AttrOf(ch));
512	    if_EXT_COLORS(SetPair(sch, GetPair(ch)));
513	    if (waddch_literal(win, sch) == ERR)
514		return ERR;
515	}
516	return (OK);
517    }
518
519    win->_curx = x;
520    win->_cury = y;
521
522    return (OK);
523}
524
525NCURSES_EXPORT(int)
526_nc_waddch_nosync(WINDOW *win, const NCURSES_CH_T c)
527/* export copy of waddch_nosync() so the string-put functions can use it */
528{
529    return (waddch_nosync(win, c));
530}
531
532/*
533 * The versions below call _nc_synchook().  We wanted to avoid this in the
534 * version exported for string puts; they'll call _nc_synchook once at end
535 * of run.
536 */
537
538/* These are actual entry points */
539
540NCURSES_EXPORT(int)
541waddch(WINDOW *win, const chtype ch)
542{
543    int code = ERR;
544    NCURSES_CH_T wch;
545    SetChar2(wch, ch);
546
547    TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_CALLED("waddch(%p, %s)"), (void *) win,
548				      _tracechtype(ch)));
549
550    if (win && (waddch_nosync(win, wch) != ERR)) {
551	_nc_synchook(win);
552	code = OK;
553    }
554
555    TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_RETURN("%d"), code));
556    return (code);
557}
558
559NCURSES_EXPORT(int)
560wechochar(WINDOW *win, const chtype ch)
561{
562    int code = ERR;
563    NCURSES_CH_T wch;
564    SetChar2(wch, ch);
565
566    TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_CALLED("wechochar(%p, %s)"),
567				      (void *) win,
568				      _tracechtype(ch)));
569
570    if (win && (waddch_nosync(win, wch) != ERR)) {
571	bool save_immed = win->_immed;
572	win->_immed = TRUE;
573	_nc_synchook(win);
574	win->_immed = save_immed;
575	code = OK;
576    }
577    TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_RETURN("%d"), code));
578    return (code);
579}
580