1/****************************************************************************
2 * Copyright (c) 1998-2004,2005 Free Software Foundation, Inc.              *
3 *                                                                          *
4 * Permission is hereby granted, free of charge, to any person obtaining a  *
5 * copy of this software and associated documentation files (the            *
6 * "Software"), to deal in the Software without restriction, including      *
7 * without limitation the rights to use, copy, modify, merge, publish,      *
8 * distribute, distribute with modifications, sublicense, and/or sell       *
9 * copies of the Software, and to permit persons to whom the Software is    *
10 * furnished to do so, subject to the following conditions:                 *
11 *                                                                          *
12 * The above copyright notice and this permission notice shall be included  *
13 * in all copies or substantial portions of the Software.                   *
14 *                                                                          *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
16 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
18 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
19 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
20 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
21 * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
22 *                                                                          *
23 * Except as contained in this notice, the name(s) of the above copyright   *
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 1.95 2005/03/27 16:52:16 tom Exp $")
40
41/*
42 * Ugly microtweaking alert.  Everything from here to end of module is
43 * likely to be speed-critical -- profiling data sure says it is!
44 * Most of the important screen-painting functions are shells around
45 * waddch().  So we make every effort to reduce function-call overhead
46 * by inlining stuff, even at the cost of making wrapped copies for
47 * export.  Also we supply some internal versions that don't call the
48 * window sync hook, for use by string-put functions.
49 */
50
51/* Return bit mask for clearing color pair number if given ch has color */
52#define COLOR_MASK(ch) (~(attr_t)((ch) & A_COLOR ? A_COLOR : 0))
53
54static inline NCURSES_CH_T
55render_char(WINDOW *win, NCURSES_CH_T ch)
56/* compute a rendition of the given char correct for the current context */
57{
58    attr_t a = win->_attrs;
59    int pair = GetPair(ch);
60
61    if (ISBLANK(ch)
62	&& AttrOf(ch) == A_NORMAL
63	&& pair == 0) {
64	/* color/pair in attrs has precedence over bkgrnd */
65	ch = win->_nc_bkgd;
66	SetAttr(ch, a | AttrOf(win->_nc_bkgd));
67	if ((pair = GET_WINDOW_PAIR(win)) == 0)
68	    pair = GetPair(win->_nc_bkgd);
69	SetPair(ch, pair);
70    } else {
71	/* color in attrs has precedence over bkgrnd */
72	a |= AttrOf(win->_nc_bkgd) & COLOR_MASK(a);
73	/* color in ch has precedence */
74	if (pair == 0) {
75	    if ((pair = GET_WINDOW_PAIR(win)) == 0)
76		pair = GetPair(win->_nc_bkgd);
77	}
78#if 0
79	if (pair > 255) {
80	    NCURSES_CH_T fixme = ch;
81	    SetPair(fixme, pair);
82	}
83#endif
84	AddAttr(ch, (a & COLOR_MASK(AttrOf(ch))));
85	SetPair(ch, pair);
86    }
87
88    TR(TRACE_VIRTPUT,
89       ("render_char bkg %s (%d), attrs %s (%d) -> ch %s (%d)",
90	_tracech_t2(1, CHREF(win->_nc_bkgd)),
91	GetPair(win->_nc_bkgd),
92	_traceattr(win->_attrs),
93	GET_WINDOW_PAIR(win),
94	_tracech_t2(3, CHREF(ch)),
95	GetPair(ch)));
96
97    return (ch);
98}
99
100NCURSES_EXPORT(NCURSES_CH_T)
101_nc_render(WINDOW *win, NCURSES_CH_T ch)
102/* make render_char() visible while still allowing us to inline it below */
103{
104    return render_char(win, ch);
105}
106
107/* check if position is legal; if not, return error */
108#ifndef NDEBUG			/* treat this like an assertion */
109#define CHECK_POSITION(win, x, y) \
110	if (y > win->_maxy \
111	 || x > win->_maxx \
112	 || y < 0 \
113	 || x < 0) { \
114		TR(TRACE_VIRTPUT, ("Alert! Win=%p _curx = %d, _cury = %d " \
115				   "(_maxx = %d, _maxy = %d)", win, x, y, \
116				   win->_maxx, win->_maxy)); \
117		return(ERR); \
118	}
119#else
120#define CHECK_POSITION(win, x, y)	/* nothing */
121#endif
122
123/*
124 * The _WRAPPED flag is useful only for telling an application that we've just
125 * wrapped the cursor.  We don't do anything with this flag except set it when
126 * wrapping, and clear it whenever we move the cursor.  If we try to wrap at
127 * the lower-right corner of a window, we cannot move the cursor (since that
128 * wouldn't be legal).  So we return an error (which is what SVr4 does).
129 * Unlike SVr4, we can successfully add a character to the lower-right corner
130 * (Solaris 2.6 does this also, however).
131 */
132static int
133wrap_to_next_line(WINDOW *win)
134{
135    win->_flags |= _WRAPPED;
136    if (++win->_cury > win->_regbottom) {
137	win->_cury = win->_regbottom;
138	win->_curx = win->_maxx;
139	if (!win->_scroll)
140	    return (ERR);
141	scroll(win);
142    }
143    win->_curx = 0;
144    return (OK);
145}
146
147#if USE_WIDEC_SUPPORT
148static int waddch_literal(WINDOW *, NCURSES_CH_T);
149/*
150 * Fill the given number of cells with blanks using the current background
151 * rendition.  This saves/restores the current x-position.
152 */
153static void
154fill_cells(WINDOW *win, int count)
155{
156    NCURSES_CH_T blank = NewChar2(BLANK_TEXT, BLANK_ATTR);
157    int save_x = win->_curx;
158    int save_y = win->_cury;
159
160    while (count-- > 0) {
161	if (waddch_literal(win, blank) == ERR)
162	    break;
163    }
164    win->_curx = save_x;
165    win->_cury = save_y;
166}
167#endif
168
169/*
170 * Build up the bytes for a multibyte character, returning the length when
171 * complete (a positive number), -1 for error and -2 for incomplete.
172 */
173#if USE_WIDEC_SUPPORT
174NCURSES_EXPORT(int)
175_nc_build_wch(WINDOW *win, ARG_CH_T ch)
176{
177    char *buffer = WINDOW_EXT(win, addch_work);
178    int len;
179    int x = win->_curx;
180    int y = win->_cury;
181    mbstate_t state;
182    wchar_t result;
183
184    if ((WINDOW_EXT(win, addch_used) != 0) &&
185	(WINDOW_EXT(win, addch_x) != x ||
186	 WINDOW_EXT(win, addch_y) != y)) {
187	/* discard the incomplete multibyte character */
188	WINDOW_EXT(win, addch_used) = 0;
189	TR(TRACE_VIRTPUT,
190	   ("Alert discarded multibyte on move (%d,%d) -> (%d,%d)",
191	    WINDOW_EXT(win, addch_y), WINDOW_EXT(win, addch_x),
192	    y, x));
193    }
194    WINDOW_EXT(win, addch_x) = x;
195    WINDOW_EXT(win, addch_y) = y;
196
197    init_mb(state);
198    buffer[WINDOW_EXT(win, addch_used)] = CharOf(CHDEREF(ch));
199    WINDOW_EXT(win, addch_used) += 1;
200    buffer[WINDOW_EXT(win, addch_used)] = '\0';
201    if ((len = mbrtowc(&result,
202		       buffer,
203		       WINDOW_EXT(win, addch_used), &state)) > 0) {
204	attr_t attrs = AttrOf(CHDEREF(ch));
205	SetChar(CHDEREF(ch), result, attrs);
206	WINDOW_EXT(win, addch_used) = 0;
207    } else {
208	if (len == -1) {
209	    /*
210	     * An error occurred.  We could either discard everything,
211	     * or assume that the error was in the previous input.
212	     * Try the latter.
213	     */
214	    TR(TRACE_VIRTPUT, ("Alert! mbrtowc returns error"));
215	    buffer[0] = CharOf(CHDEREF(ch));
216	    WINDOW_EXT(win, addch_used) = 1;
217	}
218    }
219    return len;
220}
221#endif /* USE_WIDEC_SUPPORT */
222
223static
224#if !USE_WIDEC_SUPPORT		/* cannot be inline if it is recursive */
225inline
226#endif
227int
228waddch_literal(WINDOW *win, NCURSES_CH_T ch)
229{
230    int x;
231    int y;
232    struct ldat *line;
233
234    x = win->_curx;
235    y = win->_cury;
236
237    CHECK_POSITION(win, x, y);
238
239    ch = render_char(win, ch);
240
241    line = win->_line + y;
242
243    CHANGED_CELL(line, x);
244
245    /*
246     * Build up multibyte characters until we have a wide-character.
247     */
248    if_WIDEC({
249	if (WINDOW_EXT(win, addch_used) != 0 || !Charable(ch)) {
250	    int len = _nc_build_wch(win, CHREF(ch));
251
252	    if (len > 0) {
253		if (is8bits(CharOf(ch))) {
254		    const char *s = unctrl(CharOf(ch));
255		    if (s[1] != 0) {
256			return waddstr(win, s);
257		    }
258		}
259	    } else {
260		return OK;
261	    }
262	}
263    });
264
265    /*
266     * Non-spacing characters are added to the current cell.
267     *
268     * Spacing characters that are wider than one column require some display
269     * adjustments.
270     */
271    if_WIDEC({
272	int len = wcwidth(CharOf(ch));
273	int i;
274	int j;
275
276	if (len == 0) {		/* non-spacing */
277	    if ((x > 0 && y >= 0)
278		|| ((y = win->_cury - 1) >= 0 &&
279		    (x = win->_maxx) > 0)) {
280		wchar_t *chars = (win->_line[y].text[x - 1].chars);
281		for (i = 0; i < CCHARW_MAX; ++i) {
282		    if (chars[i] == 0) {
283			TR(TRACE_VIRTPUT,
284			   ("added non-spacing %d: %x",
285			    x, (int) CharOf(ch)));
286			chars[i] = CharOf(ch);
287			break;
288		    }
289		}
290	    }
291	    goto testwrapping;
292	} else if (len > 1) {	/* multi-column characters */
293	    /*
294	     * Check if the character will fit on the current line.  If it does
295	     * not fit, fill in the remainder of the line with blanks.  and
296	     * move to the next line.
297	     */
298	    if (len > win->_maxx + 1) {
299		TR(TRACE_VIRTPUT, ("character will not fit"));
300		return ERR;
301	    } else if (x + len > win->_maxx + 1) {
302		int count = win->_maxx + 1 - x;
303		TR(TRACE_VIRTPUT, ("fill %d remaining cells", count));
304		fill_cells(win, count);
305		if (wrap_to_next_line(win) == ERR)
306		    return ERR;
307		x = win->_curx;
308		y = win->_cury;
309	    }
310	    /*
311	     * Check for cells which are orphaned by adding this character, set
312	     * those to blanks.
313	     *
314	     * FIXME: this actually could fill j-i cells, more complicated to
315	     * setup though.
316	     */
317	    for (i = 0; i < len; ++i) {
318		if (isWidecBase(win->_line[y].text[i])) {
319		    break;
320		} else if (isWidecExt(win->_line[y].text[x + i])) {
321		    for (j = i; x + j <= win->_maxx; ++j) {
322			if (!isWidecExt(win->_line[y].text[x + j])) {
323			    TR(TRACE_VIRTPUT, ("fill %d orphan cells", j));
324			    fill_cells(win, j);
325			    break;
326			}
327		    }
328		    break;
329		}
330	    }
331	    /*
332	     * Finally, add the cells for this character.
333	     */
334	    for (i = 0; i < len; ++i) {
335		NCURSES_CH_T value = ch;
336		SetWidecExt(value, i);
337		TR(TRACE_VIRTPUT, ("multicolumn %d:%d", i + 1, len));
338		line->text[x] = value;
339		CHANGED_CELL(line, x);
340		++x;
341	    }
342	    goto testwrapping;
343	}
344    });
345
346    /*
347     * Single-column characters.
348     */
349    line->text[x++] = ch;
350    /*
351     * This label is used only for wide-characters.
352     */
353    if_WIDEC(
354  testwrapping:
355    );
356
357    TR(TRACE_VIRTPUT, ("cell (%d, %d..%d) = %s",
358		       win->_cury, win->_curx, x - 1,
359		       _tracech_t(CHREF(ch))));
360
361    if (x > win->_maxx) {
362	return wrap_to_next_line(win);
363    }
364    win->_curx = x;
365    return OK;
366}
367
368static inline int
369waddch_nosync(WINDOW *win, const NCURSES_CH_T ch)
370/* the workhorse function -- add a character to the given window */
371{
372    int x, y;
373    chtype t = CharOf(ch);
374    const char *s = unctrl(t);
375
376    /*
377     * If we are using the alternate character set, forget about locale.
378     * Otherwise, if unctrl() returns a single-character or the locale
379     * claims the code is printable, treat it that way.
380     */
381    if ((AttrOf(ch) & A_ALTCHARSET)
382	|| (
383#if USE_WIDEC_SUPPORT
384	       (SP != 0 && SP->_legacy_coding) &&
385#endif
386	       s[1] == 0
387	)
388	|| (
389	       isprint(t)
390#if USE_WIDEC_SUPPORT
391	       || ((SP == 0 || !SP->_legacy_coding) &&
392		   (WINDOW_EXT(win, addch_used)
393		    || !_nc_is_charable(CharOf(ch))))
394#endif
395	))
396	return waddch_literal(win, ch);
397
398    /*
399     * Handle carriage control and other codes that are not printable, or are
400     * known to expand to more than one character according to unctrl().
401     */
402    x = win->_curx;
403    y = win->_cury;
404
405    switch (t) {
406    case '\t':
407	x += (TABSIZE - (x % TABSIZE));
408
409	/*
410	 * Space-fill the tab on the bottom line so that we'll get the
411	 * "correct" cursor position.
412	 */
413	if ((!win->_scroll && (y == win->_regbottom))
414	    || (x <= win->_maxx)) {
415	    NCURSES_CH_T blank = NewChar2(BLANK_TEXT, BLANK_ATTR);
416	    AddAttr(blank, AttrOf(ch));
417	    while (win->_curx < x) {
418		if (waddch_literal(win, blank) == ERR)
419		    return (ERR);
420	    }
421	    break;
422	} else {
423	    wclrtoeol(win);
424	    win->_flags |= _WRAPPED;
425	    if (++y > win->_regbottom) {
426		x = win->_maxx;
427		y--;
428		if (win->_scroll) {
429		    scroll(win);
430		    x = 0;
431		}
432	    } else {
433		x = 0;
434	    }
435	}
436	break;
437    case '\n':
438	wclrtoeol(win);
439	if (++y > win->_regbottom) {
440	    y--;
441	    if (win->_scroll)
442		scroll(win);
443	    else
444		return (ERR);
445	}
446	/* FALLTHRU */
447    case '\r':
448	x = 0;
449	win->_flags &= ~_WRAPPED;
450	break;
451    case '\b':
452	if (x == 0)
453	    return (OK);
454	x--;
455	win->_flags &= ~_WRAPPED;
456	break;
457    default:
458	while (*s) {
459	    NCURSES_CH_T sch;
460	    SetChar(sch, *s++, AttrOf(ch));
461	    if (waddch_literal(win, sch) == ERR)
462		return ERR;
463	}
464	return (OK);
465    }
466
467    win->_curx = x;
468    win->_cury = y;
469
470    return (OK);
471}
472
473NCURSES_EXPORT(int)
474_nc_waddch_nosync(WINDOW *win, const NCURSES_CH_T c)
475/* export copy of waddch_nosync() so the string-put functions can use it */
476{
477    return (waddch_nosync(win, c));
478}
479
480/*
481 * The versions below call _nc_synchook().  We wanted to avoid this in the
482 * version exported for string puts; they'll call _nc_synchook once at end
483 * of run.
484 */
485
486/* These are actual entry points */
487
488NCURSES_EXPORT(int)
489waddch(WINDOW *win, const chtype ch)
490{
491    int code = ERR;
492    NCURSES_CH_T wch;
493    SetChar2(wch, ch);
494
495    TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_CALLED("waddch(%p, %s)"), win,
496				      _tracechtype(ch)));
497
498    if (win && (waddch_nosync(win, wch) != ERR)) {
499	_nc_synchook(win);
500	code = OK;
501    }
502
503    TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_RETURN("%d"), code));
504    return (code);
505}
506
507NCURSES_EXPORT(int)
508wechochar(WINDOW *win, const chtype ch)
509{
510    int code = ERR;
511    NCURSES_CH_T wch;
512    SetChar2(wch, ch);
513
514    TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_CALLED("wechochar(%p, %s)"), win,
515				      _tracechtype(ch)));
516
517    if (win && (waddch_nosync(win, wch) != ERR)) {
518	bool save_immed = win->_immed;
519	win->_immed = TRUE;
520	_nc_synchook(win);
521	win->_immed = save_immed;
522	code = OK;
523    }
524    TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_RETURN("%d"), code));
525    return (code);
526}
527