lib_addch.c revision 32c0e5f07fc70b6a14d80b7df35547a163e7beaa
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3 *                                                                          *
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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 1.108 2008/02/03 18:50:27 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)] = 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	SetChar(CHDEREF(ch), result, attrs);
221	WINDOW_EXT(win, addch_used) = 0;
222    } else if (len == -1) {
223	/*
224	 * An error occurred.  We could either discard everything,
225	 * or assume that the error was in the previous input.
226	 * Try the latter.
227	 */
228	TR(TRACE_VIRTPUT, ("Alert! mbrtowc returns error"));
229	/* handle this with unctrl() */
230	WINDOW_EXT(win, addch_used) = 0;
231    }
232    return len;
233}
234#endif /* USE_WIDEC_SUPPORT */
235
236static
237#if !USE_WIDEC_SUPPORT		/* cannot be inline if it is recursive */
238NCURSES_INLINE
239#endif
240int
241waddch_literal(WINDOW *win, NCURSES_CH_T ch)
242{
243    int x;
244    int y;
245    struct ldat *line;
246
247    x = win->_curx;
248    y = win->_cury;
249
250    CHECK_POSITION(win, x, y);
251
252    ch = render_char(win, ch);
253
254    line = win->_line + y;
255
256    CHANGED_CELL(line, x);
257
258    /*
259     * Build up multibyte characters until we have a wide-character.
260     */
261    if_WIDEC({
262	if (WINDOW_EXT(win, addch_used) != 0 || !Charable(ch)) {
263	    int len = _nc_build_wch(win, CHREF(ch));
264
265	    if (len >= -1) {
266		/* handle EILSEQ */
267		if (is8bits(CharOf(ch))) {
268		    const char *s = unctrl((chtype) CharOf(ch));
269		    if (s[1] != 0) {
270			return waddstr(win, s);
271		    }
272		}
273		if (len == -1)
274		    return waddch(win, ' ');
275	    } else {
276		return OK;
277	    }
278	}
279    });
280
281    /*
282     * Non-spacing characters are added to the current cell.
283     *
284     * Spacing characters that are wider than one column require some display
285     * adjustments.
286     */
287    if_WIDEC({
288	int len = wcwidth(CharOf(ch));
289	int i;
290	int j;
291
292	if (len == 0) {		/* non-spacing */
293	    if ((x > 0 && y >= 0)
294		|| ((y = win->_cury - 1) >= 0 &&
295		    (x = win->_maxx) > 0)) {
296		wchar_t *chars = (win->_line[y].text[x - 1].chars);
297		for (i = 0; i < CCHARW_MAX; ++i) {
298		    if (chars[i] == 0) {
299			TR(TRACE_VIRTPUT,
300			   ("added non-spacing %d: %x",
301			    x, (int) CharOf(ch)));
302			chars[i] = CharOf(ch);
303			break;
304		    }
305		}
306	    }
307	    goto testwrapping;
308	} else if (len > 1) {	/* multi-column characters */
309	    /*
310	     * Check if the character will fit on the current line.  If it does
311	     * not fit, fill in the remainder of the line with blanks.  and
312	     * move to the next line.
313	     */
314	    if (len > win->_maxx + 1) {
315		TR(TRACE_VIRTPUT, ("character will not fit"));
316		return ERR;
317	    } else if (x + len > win->_maxx + 1) {
318		int count = win->_maxx + 1 - x;
319		TR(TRACE_VIRTPUT, ("fill %d remaining cells", count));
320		fill_cells(win, count);
321		if (wrap_to_next_line(win) == ERR)
322		    return ERR;
323		x = win->_curx;
324		y = win->_cury;
325	    }
326	    /*
327	     * Check for cells which are orphaned by adding this character, set
328	     * those to blanks.
329	     *
330	     * FIXME: this actually could fill j-i cells, more complicated to
331	     * setup though.
332	     */
333	    for (i = 0; i < len; ++i) {
334		if (isWidecBase(win->_line[y].text[x + i])) {
335		    break;
336		} else if (isWidecExt(win->_line[y].text[x + i])) {
337		    for (j = i; x + j <= win->_maxx; ++j) {
338			if (!isWidecExt(win->_line[y].text[x + j])) {
339			    TR(TRACE_VIRTPUT, ("fill %d orphan cells", j));
340			    fill_cells(win, j);
341			    break;
342			}
343		    }
344		    break;
345		}
346	    }
347	    /*
348	     * Finally, add the cells for this character.
349	     */
350	    for (i = 0; i < len; ++i) {
351		NCURSES_CH_T value = ch;
352		SetWidecExt(value, i);
353		TR(TRACE_VIRTPUT, ("multicolumn %d:%d (%d,%d)",
354				   i + 1, len,
355				   win->_begy + y, win->_begx + x));
356		line->text[x] = value;
357		CHANGED_CELL(line, x);
358		++x;
359	    }
360	    goto testwrapping;
361	}
362    });
363
364    /*
365     * Single-column characters.
366     */
367    line->text[x++] = ch;
368    /*
369     * This label is used only for wide-characters.
370     */
371    if_WIDEC(
372  testwrapping:
373    );
374
375    TR(TRACE_VIRTPUT, ("cell (%ld, %ld..%d) = %s",
376		       (long) win->_cury, (long) win->_curx, x - 1,
377		       _tracech_t(CHREF(ch))));
378
379    if (x > win->_maxx) {
380	return wrap_to_next_line(win);
381    }
382    win->_curx = x;
383    return OK;
384}
385
386static NCURSES_INLINE int
387waddch_nosync(WINDOW *win, const NCURSES_CH_T ch)
388/* the workhorse function -- add a character to the given window */
389{
390    NCURSES_SIZE_T x, y;
391    chtype t = CharOf(ch);
392    const char *s = unctrl(t);
393
394    /*
395     * If we are using the alternate character set, forget about locale.
396     * Otherwise, if unctrl() returns a single-character or the locale
397     * claims the code is printable, treat it that way.
398     */
399    if ((AttrOf(ch) & A_ALTCHARSET)
400	|| (
401#if USE_WIDEC_SUPPORT
402	       (SP != 0 && SP->_legacy_coding) &&
403#endif
404	       s[1] == 0
405	)
406	|| (
407	       isprint(t)
408#if USE_WIDEC_SUPPORT
409	       || ((SP == 0 || !SP->_legacy_coding) &&
410		   (WINDOW_EXT(win, addch_used)
411		    || !_nc_is_charable(CharOf(ch))))
412#endif
413	))
414	return waddch_literal(win, ch);
415
416    /*
417     * Handle carriage control and other codes that are not printable, or are
418     * known to expand to more than one character according to unctrl().
419     */
420    x = win->_curx;
421    y = win->_cury;
422
423    switch (t) {
424    case '\t':
425	x += (TABSIZE - (x % TABSIZE));
426
427	/*
428	 * Space-fill the tab on the bottom line so that we'll get the
429	 * "correct" cursor position.
430	 */
431	if ((!win->_scroll && (y == win->_regbottom))
432	    || (x <= win->_maxx)) {
433	    NCURSES_CH_T blank = blankchar;
434	    AddAttr(blank, AttrOf(ch));
435	    while (win->_curx < x) {
436		if (waddch_literal(win, blank) == ERR)
437		    return (ERR);
438	    }
439	    break;
440	} else {
441	    wclrtoeol(win);
442	    win->_flags |= _WRAPPED;
443	    if (newline_forces_scroll(win, &y)) {
444		x = win->_maxx;
445		if (win->_scroll) {
446		    scroll(win);
447		    x = 0;
448		}
449	    } else {
450		x = 0;
451	    }
452	}
453	break;
454    case '\n':
455	wclrtoeol(win);
456	if (newline_forces_scroll(win, &y)) {
457	    if (win->_scroll)
458		scroll(win);
459	    else
460		return (ERR);
461	}
462	/* FALLTHRU */
463    case '\r':
464	x = 0;
465	win->_flags &= ~_WRAPPED;
466	break;
467    case '\b':
468	if (x == 0)
469	    return (OK);
470	x--;
471	win->_flags &= ~_WRAPPED;
472	break;
473    default:
474	while (*s) {
475	    NCURSES_CH_T sch;
476	    SetChar(sch, *s++, AttrOf(ch));
477	    if (waddch_literal(win, sch) == ERR)
478		return ERR;
479	}
480	return (OK);
481    }
482
483    win->_curx = x;
484    win->_cury = y;
485
486    return (OK);
487}
488
489NCURSES_EXPORT(int)
490_nc_waddch_nosync(WINDOW *win, const NCURSES_CH_T c)
491/* export copy of waddch_nosync() so the string-put functions can use it */
492{
493    return (waddch_nosync(win, c));
494}
495
496/*
497 * The versions below call _nc_synchook().  We wanted to avoid this in the
498 * version exported for string puts; they'll call _nc_synchook once at end
499 * of run.
500 */
501
502/* These are actual entry points */
503
504NCURSES_EXPORT(int)
505waddch(WINDOW *win, const chtype ch)
506{
507    int code = ERR;
508    NCURSES_CH_T wch;
509    SetChar2(wch, ch);
510
511    TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_CALLED("waddch(%p, %s)"), win,
512				      _tracechtype(ch)));
513
514    if (win && (waddch_nosync(win, wch) != ERR)) {
515	_nc_synchook(win);
516	code = OK;
517    }
518
519    TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_RETURN("%d"), code));
520    return (code);
521}
522
523NCURSES_EXPORT(int)
524wechochar(WINDOW *win, const chtype ch)
525{
526    int code = ERR;
527    NCURSES_CH_T wch;
528    SetChar2(wch, ch);
529
530    TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_CALLED("wechochar(%p, %s)"), win,
531				      _tracechtype(ch)));
532
533    if (win && (waddch_nosync(win, wch) != ERR)) {
534	bool save_immed = win->_immed;
535	win->_immed = TRUE;
536	_nc_synchook(win);
537	win->_immed = save_immed;
538	code = OK;
539    }
540    TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_RETURN("%d"), code));
541    return (code);
542}
543