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28 
29 /*
30 **	lib_add_wch.c
31 **
32 **	The routine wadd_wch().
33 **
34 */
35 
36 #include <curses.priv.h>
37 
38 #if HAVE_WCTYPE_H
39 #include <wctype.h>
40 #endif
41 
42 MODULE_ID("$Id: lib_add_wch.c,v 1.12 2011/03/22 09:31:15 Petr.Pavlu Exp $")
43 
44 /* clone/adapt lib_addch.c */
45 static const cchar_t blankchar = NewChar(BLANK_TEXT);
46 
47 /*
48  * Ugly microtweaking alert.  Everything from here to end of module is
49  * likely to be speed-critical -- profiling data sure says it is!
50  * Most of the important screen-painting functions are shells around
51  * wadd_wch().  So we make every effort to reduce function-call overhead
52  * by inlining stuff, even at the cost of making wrapped copies for
53  * export.  Also we supply some internal versions that don't call the
54  * window sync hook, for use by string-put functions.
55  */
56 
57 /* Return bit mask for clearing color pair number if given ch has color */
58 #define COLOR_MASK(ch) (~(attr_t)((ch) & A_COLOR ? A_COLOR : 0))
59 
60 static NCURSES_INLINE cchar_t
61 render_char(WINDOW *win, cchar_t ch)
62 /* compute a rendition of the given char correct for the current context */
63 {
64     attr_t a = WINDOW_ATTRS(win);
65     int pair = GetPair(ch);
66 
67     if (ISBLANK(ch)
68 	&& AttrOf(ch) == A_NORMAL
69 	&& pair == 0) {
70 	/* color/pair in attrs has precedence over bkgrnd */
71 	ch = win->_nc_bkgd;
72 	SetAttr(ch, a | AttrOf(win->_nc_bkgd));
73 	if ((pair = GET_WINDOW_PAIR(win)) == 0)
74 	    pair = GetPair(win->_nc_bkgd);
75 	SetPair(ch, pair);
76     } else {
77 	/* color in attrs has precedence over bkgrnd */
78 	a |= AttrOf(win->_nc_bkgd) & COLOR_MASK(a);
79 	/* color in ch has precedence */
80 	if (pair == 0) {
81 	    if ((pair = GET_WINDOW_PAIR(win)) == 0)
82 		pair = GetPair(win->_nc_bkgd);
83 	}
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(WINDOW_ATTRS(win)),
93 	GET_WINDOW_PAIR(win),
94 	_tracech_t2(3, CHREF(ch)),
95 	GetPair(ch)));
96 
97     return (ch);
98 }
99 
100 /* check if position is legal; if not, return error */
101 #ifndef NDEBUG			/* treat this like an assertion */
102 #define CHECK_POSITION(win, x, y) \
103 	if (y > win->_maxy \
104 	 || x > win->_maxx \
105 	 || y < 0 \
106 	 || x < 0) { \
107 		TR(TRACE_VIRTPUT, ("Alert! Win=%p _curx = %d, _cury = %d " \
108 				   "(_maxx = %d, _maxy = %d)", win, x, y, \
109 				   win->_maxx, win->_maxy)); \
110 		return(ERR); \
111 	}
112 #else
113 #define CHECK_POSITION(win, x, y)	/* nothing */
114 #endif
115 
116 static bool
117 newline_forces_scroll(WINDOW *win, NCURSES_SIZE_T * ypos)
118 {
119     bool result = FALSE;
120 
121     if (*ypos >= win->_regtop && *ypos == win->_regbottom) {
122 	*ypos = win->_regbottom;
123 	result = TRUE;
124     } else {
125 	*ypos = (NCURSES_SIZE_T) (*ypos + 1);
126     }
127     return result;
128 }
129 
130 /*
131  * The _WRAPPED flag is useful only for telling an application that we've just
132  * wrapped the cursor.  We don't do anything with this flag except set it when
133  * wrapping, and clear it whenever we move the cursor.  If we try to wrap at
134  * the lower-right corner of a window, we cannot move the cursor (since that
135  * wouldn't be legal).  So we return an error (which is what SVr4 does).
136  * Unlike SVr4, we can successfully add a character to the lower-right corner
137  * (Solaris 2.6 does this also, however).
138  */
139 static int
140 wrap_to_next_line(WINDOW *win)
141 {
142     win->_flags |= _WRAPPED;
143     if (newline_forces_scroll(win, &(win->_cury))) {
144 	win->_curx = win->_maxx;
145 	if (!win->_scroll)
146 	    return (ERR);
147 	scroll(win);
148     }
149     win->_curx = 0;
150     return (OK);
151 }
152 
153 static int wadd_wch_literal(WINDOW *, cchar_t);
154 /*
155  * Fill the given number of cells with blanks using the current background
156  * rendition.  This saves/restores the current x-position.
157  */
158 static void
159 fill_cells(WINDOW *win, int count)
160 {
161     cchar_t blank = blankchar;
162     int save_x = win->_curx;
163     int save_y = win->_cury;
164 
165     while (count-- > 0) {
166 	if (wadd_wch_literal(win, blank) == ERR)
167 	    break;
168     }
169     win->_curx = (NCURSES_SIZE_T) save_x;
170     win->_cury = (NCURSES_SIZE_T) save_y;
171 }
172 
173 static int
174 wadd_wch_literal(WINDOW *win, cchar_t ch)
175 {
176     int x;
177     int y;
178     struct ldat *line;
179 
180     x = win->_curx;
181     y = win->_cury;
182 
183     CHECK_POSITION(win, x, y);
184 
185     ch = render_char(win, ch);
186 
187     line = win->_line + y;
188 
189     CHANGED_CELL(line, x);
190 
191     /*
192      * Non-spacing characters are added to the current cell.
193      *
194      * Spacing characters that are wider than one column require some display
195      * adjustments.
196      */
197     {
198 	int len = wcwidth(CharOf(ch));
199 	int i;
200 	int j;
201 	wchar_t *chars;
202 
203 	if (len == 0) {		/* non-spacing */
204 	    if ((x > 0 && y >= 0)
205 		|| (win->_maxx >= 0 && win->_cury >= 1)) {
206 		if (x > 0 && y >= 0)
207 		    chars = (win->_line[y].text[x - 1].chars);
208 		else
209 		    chars = (win->_line[y - 1].text[win->_maxx].chars);
210 		for (i = 0; i < CCHARW_MAX; ++i) {
211 		    if (chars[i] == 0) {
212 			TR(TRACE_VIRTPUT,
213 			   ("added non-spacing %d: %x",
214 			    x, (int) CharOf(ch)));
215 			chars[i] = CharOf(ch);
216 			break;
217 		    }
218 		}
219 	    }
220 	    goto testwrapping;
221 	} else if (len > 1) {	/* multi-column characters */
222 	    /*
223 	     * Check if the character will fit on the current line.  If it does
224 	     * not fit, fill in the remainder of the line with blanks.  and
225 	     * move to the next line.
226 	     */
227 	    if (len > win->_maxx + 1) {
228 		TR(TRACE_VIRTPUT, ("character will not fit"));
229 		return ERR;
230 	    } else if (x + len > win->_maxx + 1) {
231 		int count = win->_maxx + 1 - x;
232 		TR(TRACE_VIRTPUT, ("fill %d remaining cells", count));
233 		fill_cells(win, count);
234 		if (wrap_to_next_line(win) == ERR)
235 		    return ERR;
236 		x = win->_curx;
237 		y = win->_cury;
238 		line = win->_line + y;
239 	    }
240 	    /*
241 	     * Check for cells which are orphaned by adding this character, set
242 	     * those to blanks.
243 	     *
244 	     * FIXME: this actually could fill j-i cells, more complicated to
245 	     * setup though.
246 	     */
247 	    for (i = 0; i < len; ++i) {
248 		if (isWidecBase(win->_line[y].text[x + i])) {
249 		    break;
250 		} else if (isWidecExt(win->_line[y].text[x + i])) {
251 		    for (j = i; x + j <= win->_maxx; ++j) {
252 			if (!isWidecExt(win->_line[y].text[x + j])) {
253 			    TR(TRACE_VIRTPUT, ("fill %d orphan cells", j));
254 			    fill_cells(win, j);
255 			    break;
256 			}
257 		    }
258 		    break;
259 		}
260 	    }
261 	    /*
262 	     * Finally, add the cells for this character.
263 	     */
264 	    for (i = 0; i < len; ++i) {
265 		cchar_t value = ch;
266 		SetWidecExt(value, i);
267 		TR(TRACE_VIRTPUT, ("multicolumn %d:%d (%d,%d)",
268 				   i + 1, len,
269 				   win->_begy + y, win->_begx + x));
270 		line->text[x] = value;
271 		CHANGED_CELL(line, x);
272 		++x;
273 	    }
274 	    goto testwrapping;
275 	}
276     }
277 
278     /*
279      * Single-column characters.
280      */
281     line->text[x++] = ch;
282     /*
283      * This label is used only for wide-characters.
284      */
285   testwrapping:
286 
287     TR(TRACE_VIRTPUT, ("cell (%ld, %ld..%d) = %s",
288 		       (long) win->_cury, (long) win->_curx, x - 1,
289 		       _tracech_t(CHREF(ch))));
290 
291     if (x > win->_maxx) {
292 	return wrap_to_next_line(win);
293     }
294     win->_curx = (NCURSES_SIZE_T) x;
295     return OK;
296 }
297 
298 static NCURSES_INLINE int
299 wadd_wch_nosync(WINDOW *win, cchar_t ch)
300 /* the workhorse function -- add a character to the given window */
301 {
302     NCURSES_SIZE_T x, y;
303     wchar_t *s;
304     int tabsize = 8;
305 #if USE_REENTRANT
306     SCREEN *sp = _nc_screen_of(win);
307 #endif
308 
309     /*
310      * If we are using the alternate character set, forget about locale.
311      * Otherwise, if the locale claims the code is printable, treat it that
312      * way.
313      */
314     if ((AttrOf(ch) & A_ALTCHARSET)
315 	|| iswprint((wint_t) CharOf(ch)))
316 	return wadd_wch_literal(win, ch);
317 
318     /*
319      * Handle carriage control and other codes that are not printable, or are
320      * known to expand to more than one character according to unctrl().
321      */
322     x = win->_curx;
323     y = win->_cury;
324 
325     switch (CharOf(ch)) {
326     case '\t':
327 #if USE_REENTRANT
328 	tabsize = *ptrTabsize(sp);
329 #else
330 	tabsize = TABSIZE;
331 #endif
332 	x = (NCURSES_SIZE_T) (x + (tabsize - (x % tabsize)));
333 	/*
334 	 * Space-fill the tab on the bottom line so that we'll get the
335 	 * "correct" cursor position.
336 	 */
337 	if ((!win->_scroll && (y == win->_regbottom))
338 	    || (x <= win->_maxx)) {
339 	    cchar_t blank = blankchar;
340 	    AddAttr(blank, AttrOf(ch));
341 	    while (win->_curx < x) {
342 		if (wadd_wch_literal(win, blank) == ERR)
343 		    return (ERR);
344 	    }
345 	    break;
346 	} else {
347 	    wclrtoeol(win);
348 	    win->_flags |= _WRAPPED;
349 	    if (newline_forces_scroll(win, &y)) {
350 		x = win->_maxx;
351 		if (win->_scroll) {
352 		    scroll(win);
353 		    x = 0;
354 		}
355 	    } else {
356 		x = 0;
357 	    }
358 	}
359 	break;
360     case '\n':
361 	wclrtoeol(win);
362 	if (newline_forces_scroll(win, &y)) {
363 	    if (win->_scroll)
364 		scroll(win);
365 	    else
366 		return (ERR);
367 	}
368 	/* FALLTHRU */
369     case '\r':
370 	x = 0;
371 	win->_flags &= ~_WRAPPED;
372 	break;
373     case '\b':
374 	if (x == 0)
375 	    return (OK);
376 	x--;
377 	win->_flags &= ~_WRAPPED;
378 	break;
379     default:
380 	if ((s = wunctrl(&ch)) != 0) {
381 	    while (*s) {
382 		cchar_t sch;
383 		SetChar(sch, *s++, AttrOf(ch));
384 		if_EXT_COLORS(SetPair(sch, GetPair(ch)));
385 		if (wadd_wch_literal(win, sch) == ERR)
386 		    return ERR;
387 	    }
388 	    return OK;
389 	}
390 	return ERR;
391     }
392 
393     win->_curx = x;
394     win->_cury = y;
395 
396     return OK;
397 }
398 
399 /*
400  * The versions below call _nc_synchook().  We wanted to avoid this in the
401  * version exported for string puts; they'll call _nc_synchook once at end
402  * of run.
403  */
404 
405 /* These are actual entry points */
406 
407 NCURSES_EXPORT(int)
408 wadd_wch(WINDOW *win, const cchar_t *wch)
409 {
410     int code = ERR;
411 
412     TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_CALLED("wadd_wch(%p, %s)"),
413 				      (void *) win,
414 				      _tracecchar_t(wch)));
415 
416     if (win && (wadd_wch_nosync(win, *wch) != ERR)) {
417 	_nc_synchook(win);
418 	code = OK;
419     }
420 
421     TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_RETURN("%d"), code));
422     return (code);
423 }
424 
425 NCURSES_EXPORT(int)
426 wecho_wchar(WINDOW *win, const cchar_t *wch)
427 {
428     int code = ERR;
429 
430     TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_CALLED("wechochar(%p, %s)"),
431 				      (void *) win,
432 				      _tracecchar_t(wch)));
433 
434     if (win && (wadd_wch_nosync(win, *wch) != ERR)) {
435 	bool save_immed = win->_immed;
436 	win->_immed = TRUE;
437 	_nc_synchook(win);
438 	win->_immed = save_immed;
439 	code = OK;
440     }
441     TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_RETURN("%d"), code));
442     return (code);
443 }
444