1/****************************************************************************
2 * Copyright (c) 1998-2006,2008 Free Software Foundation, Inc.              *
3 *                                                                          *
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5 * copy of this software and associated documentation files (the            *
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9 * copies of the Software, and to permit persons to whom the Software is    *
10 * furnished to do so, subject to the following conditions:                 *
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13 * in all copies or substantial portions of the Software.                   *
14 *                                                                          *
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24 * holders shall not be used in advertising or otherwise to promote the     *
25 * sale, use or other dealings in this Software without prior written       *
26 * authorization.                                                           *
27 ****************************************************************************/
28
29/*
30**	lib_addch.c
31**
32**	The routine waddch().
33**
34*/
35
36#include <curses.priv.h>
37#include <ctype.h>
38
39MODULE_ID("$Id: lib_addch.c,v 1.113 2008/08/16 19:20:04 tom Exp $")
40
41static const NCURSES_CH_T blankchar = NewChar(BLANK_TEXT);
42
43/*
44 * Ugly microtweaking alert.  Everything from here to end of module is
45 * likely to be speed-critical -- profiling data sure says it is!
46 * Most of the important screen-painting functions are shells around
47 * waddch().  So we make every effort to reduce function-call overhead
48 * by inlining stuff, even at the cost of making wrapped copies for
49 * export.  Also we supply some internal versions that don't call the
50 * window sync hook, for use by string-put functions.
51 */
52
53/* Return bit mask for clearing color pair number if given ch has color */
54#define COLOR_MASK(ch) (~(attr_t)((ch) & A_COLOR ? A_COLOR : 0))
55
56static NCURSES_INLINE NCURSES_CH_T
57render_char(WINDOW *win, NCURSES_CH_T ch)
58/* compute a rendition of the given char correct for the current context */
59{
60    attr_t a = WINDOW_ATTRS(win);
61    int pair = GetPair(ch);
62
63    if (ISBLANK(ch)
64	&& AttrOf(ch) == A_NORMAL
65	&& pair == 0) {
66	/* color/pair in attrs has precedence over bkgrnd */
67	ch = win->_nc_bkgd;
68	SetAttr(ch, a | AttrOf(win->_nc_bkgd));
69	if ((pair = GET_WINDOW_PAIR(win)) == 0)
70	    pair = GetPair(win->_nc_bkgd);
71	SetPair(ch, pair);
72    } else {
73	/* color in attrs has precedence over bkgrnd */
74	a |= AttrOf(win->_nc_bkgd) & COLOR_MASK(a);
75	/* color in ch has precedence */
76	if (pair == 0) {
77	    if ((pair = GET_WINDOW_PAIR(win)) == 0)
78		pair = GetPair(win->_nc_bkgd);
79	}
80#if 0
81	if (pair > 255) {
82	    NCURSES_CH_T fixme = ch;
83	    SetPair(fixme, pair);
84	}
85#endif
86	AddAttr(ch, (a & COLOR_MASK(AttrOf(ch))));
87	SetPair(ch, pair);
88    }
89
90    TR(TRACE_VIRTPUT,
91       ("render_char bkg %s (%d), attrs %s (%d) -> ch %s (%d)",
92	_tracech_t2(1, CHREF(win->_nc_bkgd)),
93	GetPair(win->_nc_bkgd),
94	_traceattr(WINDOW_ATTRS(win)),
95	GET_WINDOW_PAIR(win),
96	_tracech_t2(3, CHREF(ch)),
97	GetPair(ch)));
98
99    return (ch);
100}
101
102NCURSES_EXPORT(NCURSES_CH_T)
103_nc_render(WINDOW *win, NCURSES_CH_T ch)
104/* make render_char() visible while still allowing us to inline it below */
105{
106    return render_char(win, ch);
107}
108
109/* check if position is legal; if not, return error */
110#ifndef NDEBUG			/* treat this like an assertion */
111#define CHECK_POSITION(win, x, y) \
112	if (y > win->_maxy \
113	 || x > win->_maxx \
114	 || y < 0 \
115	 || x < 0) { \
116		TR(TRACE_VIRTPUT, ("Alert! Win=%p _curx = %d, _cury = %d " \
117				   "(_maxx = %d, _maxy = %d)", win, x, y, \
118				   win->_maxx, win->_maxy)); \
119		return(ERR); \
120	}
121#else
122#define CHECK_POSITION(win, x, y)	/* nothing */
123#endif
124
125static bool
126newline_forces_scroll(WINDOW *win, NCURSES_SIZE_T * ypos)
127{
128    bool result = FALSE;
129
130    if (*ypos >= win->_regtop && *ypos == win->_regbottom) {
131	*ypos = win->_regbottom;
132	result = TRUE;
133    } else {
134	*ypos += 1;
135    }
136    return result;
137}
138
139/*
140 * The _WRAPPED flag is useful only for telling an application that we've just
141 * wrapped the cursor.  We don't do anything with this flag except set it when
142 * wrapping, and clear it whenever we move the cursor.  If we try to wrap at
143 * the lower-right corner of a window, we cannot move the cursor (since that
144 * wouldn't be legal).  So we return an error (which is what SVr4 does).
145 * Unlike SVr4, we can successfully add a character to the lower-right corner
146 * (Solaris 2.6 does this also, however).
147 */
148static int
149wrap_to_next_line(WINDOW *win)
150{
151    win->_flags |= _WRAPPED;
152    if (newline_forces_scroll(win, &(win->_cury))) {
153	win->_curx = win->_maxx;
154	if (!win->_scroll)
155	    return (ERR);
156	scroll(win);
157    }
158    win->_curx = 0;
159    return (OK);
160}
161
162#if USE_WIDEC_SUPPORT
163static int waddch_literal(WINDOW *, NCURSES_CH_T);
164/*
165 * Fill the given number of cells with blanks using the current background
166 * rendition.  This saves/restores the current x-position.
167 */
168static void
169fill_cells(WINDOW *win, int count)
170{
171    NCURSES_CH_T blank = blankchar;
172    int save_x = win->_curx;
173    int save_y = win->_cury;
174
175    while (count-- > 0) {
176	if (waddch_literal(win, blank) == ERR)
177	    break;
178    }
179    win->_curx = save_x;
180    win->_cury = save_y;
181}
182#endif
183
184/*
185 * Build up the bytes for a multibyte character, returning the length when
186 * complete (a positive number), -1 for error and -2 for incomplete.
187 */
188#if USE_WIDEC_SUPPORT
189NCURSES_EXPORT(int)
190_nc_build_wch(WINDOW *win, ARG_CH_T ch)
191{
192    char *buffer = WINDOW_EXT(win, addch_work);
193    int len;
194    int x = win->_curx;
195    int y = win->_cury;
196    mbstate_t state;
197    wchar_t result;
198
199    if ((WINDOW_EXT(win, addch_used) != 0) &&
200	(WINDOW_EXT(win, addch_x) != x ||
201	 WINDOW_EXT(win, addch_y) != y)) {
202	/* discard the incomplete multibyte character */
203	WINDOW_EXT(win, addch_used) = 0;
204	TR(TRACE_VIRTPUT,
205	   ("Alert discarded multibyte on move (%d,%d) -> (%d,%d)",
206	    WINDOW_EXT(win, addch_y), WINDOW_EXT(win, addch_x),
207	    y, x));
208    }
209    WINDOW_EXT(win, addch_x) = x;
210    WINDOW_EXT(win, addch_y) = y;
211
212    init_mb(state);
213    buffer[WINDOW_EXT(win, addch_used)] = (char) CharOf(CHDEREF(ch));
214    WINDOW_EXT(win, addch_used) += 1;
215    buffer[WINDOW_EXT(win, addch_used)] = '\0';
216    if ((len = mbrtowc(&result,
217		       buffer,
218		       WINDOW_EXT(win, addch_used), &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_WIDEC({
264	if (WINDOW_EXT(win, addch_used) != 0 || !Charable(ch)) {
265	    int len = _nc_build_wch(win, CHREF(ch));
266
267	    if (len >= -1) {
268		/* handle EILSEQ */
269		if (is8bits(CharOf(ch))) {
270		    const char *s = unctrl((chtype) CharOf(ch));
271		    if (s[1] != 0) {
272			return waddstr(win, s);
273		    }
274		}
275		if (len == -1)
276		    return waddch(win, ' ');
277	    } else {
278		return OK;
279	    }
280	}
281    });
282
283    /*
284     * Non-spacing characters are added to the current cell.
285     *
286     * Spacing characters that are wider than one column require some display
287     * adjustments.
288     */
289    if_WIDEC({
290	int len = wcwidth(CharOf(ch));
291	int i;
292	int j;
293	wchar_t *chars;
294
295	if (len == 0) {		/* non-spacing */
296	    if ((x > 0 && y >= 0)
297		|| (win->_maxx >= 0 && win->_cury >= 1)) {
298		if (x > 0 && y >= 0)
299		    chars = (win->_line[y].text[x - 1].chars);
300		else
301		    chars = (win->_line[y - 1].text[win->_maxx].chars);
302		for (i = 0; i < CCHARW_MAX; ++i) {
303		    if (chars[i] == 0) {
304			TR(TRACE_VIRTPUT,
305			   ("added non-spacing %d: %x",
306			    x, (int) CharOf(ch)));
307			chars[i] = CharOf(ch);
308			break;
309		    }
310		}
311	    }
312	    goto testwrapping;
313	} else if (len > 1) {	/* multi-column characters */
314	    /*
315	     * Check if the character will fit on the current line.  If it does
316	     * not fit, fill in the remainder of the line with blanks.  and
317	     * move to the next line.
318	     */
319	    if (len > win->_maxx + 1) {
320		TR(TRACE_VIRTPUT, ("character will not fit"));
321		return ERR;
322	    } else if (x + len > win->_maxx + 1) {
323		int count = win->_maxx + 1 - x;
324		TR(TRACE_VIRTPUT, ("fill %d remaining cells", count));
325		fill_cells(win, count);
326		if (wrap_to_next_line(win) == ERR)
327		    return ERR;
328		x = win->_curx;
329		y = win->_cury;
330	    }
331	    /*
332	     * Check for cells which are orphaned by adding this character, set
333	     * those to blanks.
334	     *
335	     * FIXME: this actually could fill j-i cells, more complicated to
336	     * setup though.
337	     */
338	    for (i = 0; i < len; ++i) {
339		if (isWidecBase(win->_line[y].text[x + i])) {
340		    break;
341		} else if (isWidecExt(win->_line[y].text[x + i])) {
342		    for (j = i; x + j <= win->_maxx; ++j) {
343			if (!isWidecExt(win->_line[y].text[x + j])) {
344			    TR(TRACE_VIRTPUT, ("fill %d orphan cells", j));
345			    fill_cells(win, j);
346			    break;
347			}
348		    }
349		    break;
350		}
351	    }
352	    /*
353	     * Finally, add the cells for this character.
354	     */
355	    for (i = 0; i < len; ++i) {
356		NCURSES_CH_T value = ch;
357		SetWidecExt(value, i);
358		TR(TRACE_VIRTPUT, ("multicolumn %d:%d (%d,%d)",
359				   i + 1, len,
360				   win->_begy + y, win->_begx + x));
361		line->text[x] = value;
362		CHANGED_CELL(line, x);
363		++x;
364	    }
365	    goto testwrapping;
366	}
367    });
368
369    /*
370     * Single-column characters.
371     */
372    line->text[x++] = ch;
373    /*
374     * This label is used only for wide-characters.
375     */
376    if_WIDEC(
377  testwrapping:
378    );
379
380    TR(TRACE_VIRTPUT, ("cell (%ld, %ld..%d) = %s",
381		       (long) win->_cury, (long) win->_curx, x - 1,
382		       _tracech_t(CHREF(ch))));
383
384    if (x > win->_maxx) {
385	return wrap_to_next_line(win);
386    }
387    win->_curx = x;
388    return OK;
389}
390
391static NCURSES_INLINE int
392waddch_nosync(WINDOW *win, const NCURSES_CH_T ch)
393/* the workhorse function -- add a character to the given window */
394{
395    NCURSES_SIZE_T x, y;
396    chtype t = CharOf(ch);
397    const char *s = unctrl(t);
398
399    /*
400     * If we are using the alternate character set, forget about locale.
401     * Otherwise, if unctrl() returns a single-character or the locale
402     * claims the code is printable, treat it that way.
403     */
404    if ((AttrOf(ch) & A_ALTCHARSET)
405	|| (
406#if USE_WIDEC_SUPPORT
407	       (SP != 0 && SP->_legacy_coding) &&
408#endif
409	       s[1] == 0
410	)
411	|| (
412	       isprint(t)
413#if USE_WIDEC_SUPPORT
414	       || ((SP == 0 || !SP->_legacy_coding) &&
415		   (WINDOW_EXT(win, addch_used)
416		    || !_nc_is_charable(CharOf(ch))))
417#endif
418	))
419	return waddch_literal(win, ch);
420
421    /*
422     * Handle carriage control and other codes that are not printable, or are
423     * known to expand to more than one character according to unctrl().
424     */
425    x = win->_curx;
426    y = win->_cury;
427
428    switch (t) {
429    case '\t':
430	x += (TABSIZE - (x % TABSIZE));
431
432	/*
433	 * Space-fill the tab on the bottom line so that we'll get the
434	 * "correct" cursor position.
435	 */
436	if ((!win->_scroll && (y == win->_regbottom))
437	    || (x <= win->_maxx)) {
438	    NCURSES_CH_T blank = blankchar;
439	    AddAttr(blank, AttrOf(ch));
440	    while (win->_curx < x) {
441		if (waddch_literal(win, blank) == ERR)
442		    return (ERR);
443	    }
444	    break;
445	} else {
446	    wclrtoeol(win);
447	    win->_flags |= _WRAPPED;
448	    if (newline_forces_scroll(win, &y)) {
449		x = win->_maxx;
450		if (win->_scroll) {
451		    scroll(win);
452		    x = 0;
453		}
454	    } else {
455		x = 0;
456	    }
457	}
458	break;
459    case '\n':
460	wclrtoeol(win);
461	if (newline_forces_scroll(win, &y)) {
462	    if (win->_scroll)
463		scroll(win);
464	    else
465		return (ERR);
466	}
467	/* FALLTHRU */
468    case '\r':
469	x = 0;
470	win->_flags &= ~_WRAPPED;
471	break;
472    case '\b':
473	if (x == 0)
474	    return (OK);
475	x--;
476	win->_flags &= ~_WRAPPED;
477	break;
478    default:
479	while (*s) {
480	    NCURSES_CH_T sch;
481	    SetChar(sch, *s++, AttrOf(ch));
482	    if_EXT_COLORS(SetPair(sch, GetPair(ch)));
483	    if (waddch_literal(win, sch) == ERR)
484		return ERR;
485	}
486	return (OK);
487    }
488
489    win->_curx = x;
490    win->_cury = y;
491
492    return (OK);
493}
494
495NCURSES_EXPORT(int)
496_nc_waddch_nosync(WINDOW *win, const NCURSES_CH_T c)
497/* export copy of waddch_nosync() so the string-put functions can use it */
498{
499    return (waddch_nosync(win, c));
500}
501
502/*
503 * The versions below call _nc_synchook().  We wanted to avoid this in the
504 * version exported for string puts; they'll call _nc_synchook once at end
505 * of run.
506 */
507
508/* These are actual entry points */
509
510NCURSES_EXPORT(int)
511waddch(WINDOW *win, const chtype ch)
512{
513    int code = ERR;
514    NCURSES_CH_T wch;
515    SetChar2(wch, ch);
516
517    TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_CALLED("waddch(%p, %s)"), win,
518				      _tracechtype(ch)));
519
520    if (win && (waddch_nosync(win, wch) != ERR)) {
521	_nc_synchook(win);
522	code = OK;
523    }
524
525    TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_RETURN("%d"), code));
526    return (code);
527}
528
529NCURSES_EXPORT(int)
530wechochar(WINDOW *win, const chtype ch)
531{
532    int code = ERR;
533    NCURSES_CH_T wch;
534    SetChar2(wch, ch);
535
536    TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_CALLED("wechochar(%p, %s)"), win,
537				      _tracechtype(ch)));
538
539    if (win && (waddch_nosync(win, wch) != ERR)) {
540	bool save_immed = win->_immed;
541	win->_immed = TRUE;
542	_nc_synchook(win);
543	win->_immed = save_immed;
544	code = OK;
545    }
546    TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_RETURN("%d"), code));
547    return (code);
548}
549