1/****************************************************************************
2 * Copyright 2020 Thomas E. Dickey                                          *
3 * Copyright 1998-2013,2016 Free Software Foundation, Inc.                  *
4 *                                                                          *
5 * Permission is hereby granted, free of charge, to any person obtaining a  *
6 * copy of this software and associated documentation files (the            *
7 * "Software"), to deal in the Software without restriction, including      *
8 * without limitation the rights to use, copy, modify, merge, publish,      *
9 * distribute, distribute with modifications, sublicense, and/or sell       *
10 * copies of the Software, and to permit persons to whom the Software is    *
11 * furnished to do so, subject to the following conditions:                 *
12 *                                                                          *
13 * The above copyright notice and this permission notice shall be included  *
14 * in all copies or substantial portions of the Software.                   *
15 *                                                                          *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
19 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
20 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
21 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
22 * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
23 *                                                                          *
24 * Except as contained in this notice, the name(s) of the above copyright   *
25 * holders shall not be used in advertising or otherwise to promote the     *
26 * sale, use or other dealings in this Software without prior written       *
27 * authorization.                                                           *
28 ****************************************************************************/
29
30/****************************************************************************
31 *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
32 *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
33 ****************************************************************************/
34
35/*
36**	lib_overlay.c
37**
38**	The routines overlay(), copywin(), and overwrite().
39**
40*/
41
42#include <curses.priv.h>
43
44MODULE_ID("$Id: lib_overlay.c,v 1.33 2020/02/02 23:34:34 tom Exp $")
45
46static int
47overlap(const WINDOW *const src, WINDOW *const dst, int const flag)
48{
49    int rc = ERR;
50
51    T((T_CALLED("overlap(%p,%p,%d)"), (const void *) src, (void *) dst, flag));
52
53    if (src != 0 && dst != 0) {
54	int sx1, sy1, sx2, sy2;
55	int dx1, dy1, dx2, dy2;
56
57	_nc_lock_global(curses);
58
59	T(("src : begy %ld, begx %ld, maxy %ld, maxx %ld",
60	   (long) src->_begy,
61	   (long) src->_begx,
62	   (long) src->_maxy,
63	   (long) src->_maxx));
64	T(("dst : begy %ld, begx %ld, maxy %ld, maxx %ld",
65	   (long) dst->_begy,
66	   (long) dst->_begx,
67	   (long) dst->_maxy,
68	   (long) dst->_maxx));
69
70	sx1 = src->_begx;
71	sy1 = src->_begy;
72	sx2 = sx1 + src->_maxx;
73	sy2 = sy1 + src->_maxy;
74
75	dx1 = dst->_begx;
76	dy1 = dst->_begy;
77	dx2 = dx1 + dst->_maxx;
78	dy2 = dy1 + dst->_maxy;
79
80	if (dx2 >= sx1 && dx1 <= sx2 && dy2 >= sy1 && dy1 <= sy2) {
81	    int sminrow = max(sy1, dy1) - sy1;
82	    int smincol = max(sx1, dx1) - sx1;
83	    int dminrow = max(sy1, dy1) - dy1;
84	    int dmincol = max(sx1, dx1) - dx1;
85	    int dmaxrow = min(sy2, dy2) - dy1;
86	    int dmaxcol = min(sx2, dx2) - dx1;
87
88	    rc = copywin(src, dst,
89			 sminrow, smincol,
90			 dminrow, dmincol,
91			 dmaxrow, dmaxcol,
92			 flag);
93	}
94	_nc_unlock_global(curses);
95    }
96    returnCode(rc);
97}
98
99/*
100**
101**	overlay(win1, win2)
102**
103**
104**	overlay() writes the overlapping area of win1 behind win2
105**	on win2 non-destructively.
106**
107**/
108
109NCURSES_EXPORT(int)
110overlay(const WINDOW *win1, WINDOW *win2)
111{
112    T((T_CALLED("overlay(%p,%p)"), (const void *) win1, (void *) win2));
113    returnCode(overlap(win1, win2, TRUE));
114}
115
116/*
117**
118**	overwrite(win1, win2)
119**
120**
121**	overwrite() writes the overlapping area of win1 behind win2
122**	on win2 destructively.
123**
124**/
125
126NCURSES_EXPORT(int)
127overwrite(const WINDOW *win1, WINDOW *win2)
128{
129    T((T_CALLED("overwrite(%p,%p)"), (const void *) win1, (void *) win2));
130    returnCode(overlap(win1, win2, FALSE));
131}
132
133NCURSES_EXPORT(int)
134copywin(const WINDOW *src, WINDOW *dst,
135	int sminrow, int smincol,
136	int dminrow, int dmincol,
137	int dmaxrow, int dmaxcol,
138	int over)
139{
140    int rc = ERR;
141
142    T((T_CALLED("copywin(%p, %p, %d, %d, %d, %d, %d, %d, %d)"),
143       (const void *) src,
144       (void *) dst,
145       sminrow, smincol,
146       dminrow, dmincol,
147       dmaxrow, dmaxcol, over));
148
149    if (src != 0
150	&& dst != 0
151	&& dmaxrow >= dminrow
152	&& dmaxcol >= dmincol) {
153	attr_t bk;
154	attr_t mask;
155
156	_nc_lock_global(curses);
157
158	bk = AttrOf(dst->_nc_bkgd);
159	mask = ~(attr_t) ((bk & A_COLOR) ? A_COLOR : 0);
160
161	/* make sure rectangle exists in source */
162	if ((sminrow + dmaxrow - dminrow) <= (src->_maxy + 1) &&
163	    (smincol + dmaxcol - dmincol) <= (src->_maxx + 1)) {
164
165	    T(("rectangle exists in source"));
166
167	    /* make sure rectangle fits in destination */
168	    if (dmaxrow <= dst->_maxy && dmaxcol <= dst->_maxx) {
169		int sx, sy, dx, dy;
170		bool copied = FALSE;
171
172		T(("rectangle fits in destination"));
173
174		for (dy = dminrow, sy = sminrow;
175		     dy <= dmaxrow;
176		     sy++, dy++) {
177		    bool touched;
178
179		    if (dy < 0 || sy < 0)
180			continue;
181
182		    touched = FALSE;
183		    for (dx = dmincol, sx = smincol;
184			 dx <= dmaxcol;
185			 sx++, dx++) {
186
187			if (dx < 0 || sx < 0)
188			    continue;
189			copied = TRUE;
190
191			if (over) {
192			    if ((CharOf(src->_line[sy].text[sx]) != L(' ')) &&
193				(!CharEq(dst->_line[dy].text[dx],
194					 src->_line[sy].text[sx]))) {
195				dst->_line[dy].text[dx] =
196				    src->_line[sy].text[sx];
197				SetAttr(dst->_line[dy].text[dx],
198					((AttrOf(src->_line[sy].text[sx]) &
199					  mask) | bk));
200				touched = TRUE;
201			    }
202			} else {
203			    if (!CharEq(dst->_line[dy].text[dx],
204					src->_line[sy].text[sx])) {
205				dst->_line[dy].text[dx] =
206				    src->_line[sy].text[sx];
207				touched = TRUE;
208			    }
209			}
210		    }
211		    if (touched) {
212			touchline(dst, dminrow, (dmaxrow - dminrow + 1));
213		    }
214		}
215		T(("finished copywin"));
216		if (copied)
217		    rc = OK;
218	    }
219	}
220	_nc_unlock_global(curses);
221    }
222    returnCode(rc);
223}
224