1/****************************************************************************
2 * Copyright (c) 1998-2009,2010 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 *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
31 *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
32 *     and: Thomas E. Dickey                        1996-on                 *
33 *     and: Juergen Pfeifer                         2009                    *
34 ****************************************************************************/
35
36/*
37 * lib_pad.c
38 * newpad	-- create a new pad
39 * pnoutrefresh -- refresh a pad, no update
40 * pechochar	-- add a char to a pad and refresh
41 */
42
43#include <curses.priv.h>
44
45MODULE_ID("$Id: lib_pad.c,v 1.46 2010/04/24 23:50:45 tom Exp $")
46
47NCURSES_EXPORT(WINDOW *)
48NCURSES_SP_NAME(newpad) (NCURSES_SP_DCLx int l, int c)
49{
50    WINDOW *win;
51    NCURSES_CH_T *ptr;
52    int i;
53
54    T((T_CALLED("newpad(%p,%d, %d)"), (void *) SP_PARM, l, c));
55
56    if (l <= 0 || c <= 0)
57	returnWin(0);
58
59    win = NCURSES_SP_NAME(_nc_makenew) (NCURSES_SP_ARGx l, c, 0, 0, _ISPAD);
60    if (win == NULL)
61	returnWin(0);
62
63    for (i = 0; i < l; i++) {
64	if_USE_SCROLL_HINTS(win->_line[i].oldindex = _NEWINDEX);
65	if ((win->_line[i].text = typeCalloc(NCURSES_CH_T, ((size_t) c))) == 0) {
66	    (void) _nc_freewin(win);
67	    returnWin(0);
68	}
69	for (ptr = win->_line[i].text; ptr < win->_line[i].text + c; ptr++)
70	    SetChar(*ptr, BLANK_TEXT, BLANK_ATTR);
71    }
72
73    returnWin(win);
74}
75
76#if NCURSES_SP_FUNCS
77NCURSES_EXPORT(WINDOW *)
78newpad(int l, int c)
79{
80    return NCURSES_SP_NAME(newpad) (CURRENT_SCREEN, l, c);
81}
82#endif
83
84NCURSES_EXPORT(WINDOW *)
85subpad(WINDOW *orig, int l, int c, int begy, int begx)
86{
87    WINDOW *win = (WINDOW *) 0;
88
89    T((T_CALLED("subpad(%d, %d)"), l, c));
90
91    if (orig) {
92	if (!(orig->_flags & _ISPAD)
93	    || ((win = derwin(orig, l, c, begy, begx)) == NULL))
94	    returnWin(0);
95    }
96    returnWin(win);
97}
98
99NCURSES_EXPORT(int)
100prefresh(WINDOW *win,
101	 int pminrow,
102	 int pmincol,
103	 int sminrow,
104	 int smincol,
105	 int smaxrow,
106	 int smaxcol)
107{
108#if NCURSES_SP_FUNCS
109    SCREEN *sp = _nc_screen_of(win);
110#endif
111
112    T((T_CALLED("prefresh()")));
113    if (pnoutrefresh(win, pminrow, pmincol, sminrow, smincol, smaxrow,
114		     smaxcol) != ERR
115	&& NCURSES_SP_NAME(doupdate) (NCURSES_SP_ARG) != ERR) {
116	returnCode(OK);
117    }
118    returnCode(ERR);
119}
120
121NCURSES_EXPORT(int)
122pnoutrefresh(WINDOW *win,
123	     int pminrow,
124	     int pmincol,
125	     int sminrow,
126	     int smincol,
127	     int smaxrow,
128	     int smaxcol)
129{
130    int i, j;
131    int m, n;
132    int pmaxrow;
133    int pmaxcol;
134    SCREEN *sp;
135
136#if USE_SCROLL_HINTS
137    const int my_len = 2;	/* parameterize the threshold for hardscroll */
138    NCURSES_SIZE_T displaced;
139    bool wide;
140#endif
141
142    T((T_CALLED("pnoutrefresh(%p, %d, %d, %d, %d, %d, %d)"),
143       (void *) win, pminrow, pmincol, sminrow, smincol, smaxrow, smaxcol));
144
145    if (win == 0)
146	returnCode(ERR);
147
148    if (!(win->_flags & _ISPAD))
149	returnCode(ERR);
150
151    sp = _nc_screen_of(win);
152
153    /* negative values are interpreted as zero */
154    if (pminrow < 0)
155	pminrow = 0;
156    if (pmincol < 0)
157	pmincol = 0;
158    if (sminrow < 0)
159	sminrow = 0;
160    if (smincol < 0)
161	smincol = 0;
162
163    pmaxrow = pminrow + smaxrow - sminrow;
164    pmaxcol = pmincol + smaxcol - smincol;
165
166    T((" pminrow + smaxrow - sminrow %ld, win->_maxy %ld",
167       (long) pmaxrow, (long) win->_maxy));
168    T((" pmincol + smaxcol - smincol %ld, win->_maxx %ld",
169       (long) pmaxcol, (long) win->_maxx));
170
171    /*
172     * Trim the caller's screen size back to the actual limits.
173     */
174    if (pmaxrow > win->_maxy) {
175	smaxrow -= (pmaxrow - win->_maxy);
176	pmaxrow = pminrow + smaxrow - sminrow;
177    }
178    if (pmaxcol > win->_maxx) {
179	smaxcol -= (pmaxcol - win->_maxx);
180	pmaxcol = pmincol + smaxcol - smincol;
181    }
182
183    if (smaxrow >= screen_lines(sp)
184	|| smaxcol >= screen_columns(sp)
185	|| sminrow > smaxrow
186	|| smincol > smaxcol)
187	returnCode(ERR);
188
189    T(("pad being refreshed"));
190
191#if USE_SCROLL_HINTS
192    if (win->_pad._pad_y >= 0) {
193	displaced = pminrow - win->_pad._pad_y
194	    - (sminrow - win->_pad._pad_top);
195	T(("pad being shifted by %d line(s)", displaced));
196    } else
197	displaced = 0;
198#endif
199
200    /*
201     * For pure efficiency, we'd want to transfer scrolling information
202     * from the pad to newscr whenever the window is wide enough that
203     * its update will dominate the cost of the update for the horizontal
204     * band of newscr that it occupies.  Unfortunately, this threshold
205     * tends to be complex to estimate, and in any case scrolling the
206     * whole band and rewriting the parts outside win's image would look
207     * really ugly.  So.  What we do is consider the pad "wide" if it
208     * either (a) occupies the whole width of newscr, or (b) occupies
209     * all but at most one column on either vertical edge of the screen
210     * (this caters to fussy people who put boxes around full-screen
211     * windows).  Note that changing this formula will not break any code,
212     * merely change the costs of various update cases.
213     */
214#if USE_SCROLL_HINTS
215    wide = (smincol < my_len && smaxcol > (NewScreen(sp)->_maxx - my_len));
216#endif
217
218    for (i = pminrow, m = sminrow + win->_yoffset;
219	 i <= pmaxrow && m <= NewScreen(sp)->_maxy;
220	 i++, m++) {
221	register struct ldat *nline = &NewScreen(sp)->_line[m];
222	register struct ldat *oline = &win->_line[i];
223	for (j = pmincol, n = smincol; j <= pmaxcol; j++, n++) {
224	    NCURSES_CH_T ch = oline->text[j];
225#if USE_WIDEC_SUPPORT
226	    /*
227	     * Special case for leftmost character of the displayed area.
228	     * Only half of a double-width character may be visible.
229	     */
230	    if (j == pmincol
231		&& j > 0
232		&& isWidecExt(ch)) {
233		SetChar(ch, L(' '), AttrOf(oline->text[j - 1]));
234	    }
235#endif
236	    if (!CharEq(ch, nline->text[n])) {
237		nline->text[n] = ch;
238		CHANGED_CELL(nline, n);
239	    }
240	}
241
242#if USE_SCROLL_HINTS
243	if (wide) {
244	    int nind = m + displaced;
245	    if (oline->oldindex < 0
246		|| nind < sminrow
247		|| nind > smaxrow) {
248		nind = _NEWINDEX;
249	    } else if (displaced) {
250		register struct ldat *pline = &CurScreen(sp)->_line[nind];
251		for (j = 0; j <= my_len; j++) {
252		    int k = NewScreen(sp)->_maxx - j;
253		    if (pline->text[j] != nline->text[j]
254			|| pline->text[k] != nline->text[k]) {
255			nind = _NEWINDEX;
256			break;
257		    }
258		}
259	    }
260
261	    nline->oldindex = nind;
262	}
263#endif /* USE_SCROLL_HINTS */
264	oline->firstchar = oline->lastchar = _NOCHANGE;
265	if_USE_SCROLL_HINTS(oline->oldindex = i);
266    }
267
268    /*
269     * Clean up debris from scrolling or resizing the pad, so we do not
270     * accidentally pick up the index value during the next call to this
271     * procedure.  The only rows that should have an index value are those
272     * that are displayed during this cycle.
273     */
274#if USE_SCROLL_HINTS
275    for (i = pminrow - 1; (i >= 0) && (win->_line[i].oldindex >= 0); i--)
276	win->_line[i].oldindex = _NEWINDEX;
277    for (i = pmaxrow + 1; (i <= win->_maxy)
278	 && (win->_line[i].oldindex >= 0); i++)
279	win->_line[i].oldindex = _NEWINDEX;
280#endif
281
282    win->_begx = (NCURSES_SIZE_T) smincol;
283    win->_begy = (NCURSES_SIZE_T) sminrow;
284
285    if (win->_clear) {
286	win->_clear = FALSE;
287	NewScreen(sp)->_clear = TRUE;
288    }
289
290    /*
291     * Use the pad's current position, if it will be visible.
292     * If not, don't do anything; it's not an error.
293     */
294    if (win->_leaveok == FALSE
295	&& win->_cury >= pminrow
296	&& win->_curx >= pmincol
297	&& win->_cury <= pmaxrow
298	&& win->_curx <= pmaxcol) {
299	NewScreen(sp)->_cury = (NCURSES_SIZE_T) (win->_cury - pminrow
300						 + win->_begy + win->_yoffset);
301	NewScreen(sp)->_curx = (NCURSES_SIZE_T) (win->_curx - pmincol
302						 + win->_begx);
303    }
304    NewScreen(sp)->_leaveok = win->_leaveok;
305    win->_flags &= ~_HASMOVED;
306
307    /*
308     * Update our cache of the line-numbers that we displayed from the pad.
309     * We will use this on subsequent calls to this function to derive
310     * values to stuff into 'oldindex[]' -- for scrolling optimization.
311     */
312    win->_pad._pad_y = (NCURSES_SIZE_T) pminrow;
313    win->_pad._pad_x = (NCURSES_SIZE_T) pmincol;
314    win->_pad._pad_top = (NCURSES_SIZE_T) sminrow;
315    win->_pad._pad_left = (NCURSES_SIZE_T) smincol;
316    win->_pad._pad_bottom = (NCURSES_SIZE_T) smaxrow;
317    win->_pad._pad_right = (NCURSES_SIZE_T) smaxcol;
318
319    returnCode(OK);
320}
321
322NCURSES_EXPORT(int)
323pechochar(WINDOW *pad, const chtype ch)
324{
325    T((T_CALLED("pechochar(%p, %s)"), (void *) pad, _tracechtype(ch)));
326
327    if (pad == 0)
328	returnCode(ERR);
329
330    if (!(pad->_flags & _ISPAD))
331	returnCode(wechochar(pad, ch));
332
333    waddch(pad, ch);
334    prefresh(pad, pad->_pad._pad_y,
335	     pad->_pad._pad_x,
336	     pad->_pad._pad_top,
337	     pad->_pad._pad_left,
338	     pad->_pad._pad_bottom,
339	     pad->_pad._pad_right);
340
341    returnCode(OK);
342}
343