xref: /openbsd/lib/libcurses/base/wresize.c (revision 09467b48)
1 /* $OpenBSD: wresize.c,v 1.5 2010/01/12 23:22:06 nicm Exp $ */
2 
3 /****************************************************************************
4  * Copyright (c) 1998-2007,2008 Free Software Foundation, Inc.              *
5  *                                                                          *
6  * Permission is hereby granted, free of charge, to any person obtaining a  *
7  * copy of this software and associated documentation files (the            *
8  * "Software"), to deal in the Software without restriction, including      *
9  * without limitation the rights to use, copy, modify, merge, publish,      *
10  * distribute, distribute with modifications, sublicense, and/or sell       *
11  * copies of the Software, and to permit persons to whom the Software is    *
12  * furnished to do so, subject to the following conditions:                 *
13  *                                                                          *
14  * The above copyright notice and this permission notice shall be included  *
15  * in all copies or substantial portions of the Software.                   *
16  *                                                                          *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
20  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
21  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
22  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
23  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
24  *                                                                          *
25  * Except as contained in this notice, the name(s) of the above copyright   *
26  * holders shall not be used in advertising or otherwise to promote the     *
27  * sale, use or other dealings in this Software without prior written       *
28  * authorization.                                                           *
29  ****************************************************************************/
30 
31 /****************************************************************************
32  *  Author: Thomas E. Dickey 1996-2002                                      *
33  ****************************************************************************/
34 
35 #include <curses.priv.h>
36 
37 MODULE_ID("$Id: wresize.c,v 1.5 2010/01/12 23:22:06 nicm Exp $")
38 
39 static int
40 cleanup_lines(struct ldat *data, int length)
41 {
42     while (--length >= 0)
43 	free(data[length].text);
44     free(data);
45     return ERR;
46 }
47 
48 /*
49  * If we have reallocated the ldat structs, we will have to repair pointers
50  * used in subwindows.
51  */
52 static void
53 repair_subwindows(WINDOW *cmp)
54 {
55     WINDOWLIST *wp;
56     struct ldat *pline = cmp->_line;
57     int row;
58 
59     _nc_lock_global(curses);
60 
61     for (each_window(wp)) {
62 	WINDOW *tst = &(wp->win);
63 
64 	if (tst->_parent == cmp) {
65 
66 	    if (tst->_pary > cmp->_maxy)
67 		tst->_pary = cmp->_maxy;
68 	    if (tst->_parx > cmp->_maxx)
69 		tst->_parx = cmp->_maxx;
70 
71 	    if (tst->_maxy + tst->_pary > cmp->_maxy)
72 		tst->_maxy = cmp->_maxy - tst->_pary;
73 	    if (tst->_maxx + tst->_parx > cmp->_maxx)
74 		tst->_maxx = cmp->_maxx - tst->_parx;
75 
76 	    for (row = 0; row <= tst->_maxy; ++row) {
77 		tst->_line[row].text = &pline[tst->_pary + row].text[tst->_parx];
78 	    }
79 	    repair_subwindows(tst);
80 	}
81     }
82     _nc_unlock_global(curses);
83 }
84 
85 /*
86  * Reallocate a curses WINDOW struct to either shrink or grow to the specified
87  * new lines/columns.  If it grows, the new character cells are filled with
88  * blanks.  The application is responsible for repainting the blank area.
89  */
90 NCURSES_EXPORT(int)
91 wresize(WINDOW *win, int ToLines, int ToCols)
92 {
93     int col, row, size_x, size_y;
94     struct ldat *pline;
95     struct ldat *new_lines = 0;
96 
97 #ifdef TRACE
98     T((T_CALLED("wresize(%p,%d,%d)"), win, ToLines, ToCols));
99     if (win) {
100 	TR(TRACE_UPDATE, ("...beg (%ld, %ld), max(%ld,%ld), reg(%ld,%ld)",
101 			  (long) win->_begy, (long) win->_begx,
102 			  (long) win->_maxy, (long) win->_maxx,
103 			  (long) win->_regtop, (long) win->_regbottom));
104 	if (USE_TRACEF(TRACE_UPDATE)) {
105 	    _tracedump("...before", win);
106 	    _nc_unlock_global(tracef);
107 	}
108     }
109 #endif
110 
111     if (!win || --ToLines < 0 || --ToCols < 0)
112 	returnCode(ERR);
113 
114     size_x = win->_maxx;
115     size_y = win->_maxy;
116 
117     if (ToLines == size_y
118 	&& ToCols == size_x)
119 	returnCode(OK);
120 
121     if ((win->_flags & _SUBWIN)) {
122 	/*
123 	 * Check if the new limits will fit into the parent window's size.  If
124 	 * not, do not resize.  We could adjust the location of the subwindow,
125 	 * but the application may not like that.
126 	 */
127 	if (win->_pary + ToLines > win->_parent->_maxy
128 	    || win->_parx + ToCols > win->_parent->_maxx) {
129 	    returnCode(ERR);
130 	}
131 	pline = win->_parent->_line;
132     } else {
133 	pline = 0;
134     }
135 
136     /*
137      * Allocate new memory as needed.  Do the allocations without modifying
138      * the original window, in case an allocation fails.  Always allocate
139      * (at least temporarily) the array pointing to the individual lines.
140      */
141     new_lines = typeCalloc(struct ldat, (unsigned) (ToLines + 1));
142     if (new_lines == 0)
143 	returnCode(ERR);
144 
145     /*
146      * For each line in the target, allocate or adjust pointers for the
147      * corresponding text, depending on whether this is a window or a
148      * subwindow.
149      */
150     for (row = 0; row <= ToLines; ++row) {
151 	int begin = (row > size_y) ? 0 : (size_x + 1);
152 	int end = ToCols;
153 	NCURSES_CH_T *s;
154 
155 	if (!(win->_flags & _SUBWIN)) {
156 	    if (row <= size_y) {
157 		if (ToCols != size_x) {
158 		    if ((s = typeMalloc(NCURSES_CH_T, ToCols + 1)) == 0)
159 			returnCode(cleanup_lines(new_lines, row));
160 		    for (col = 0; col <= ToCols; ++col) {
161 			s[col] = (col <= size_x
162 				  ? win->_line[row].text[col]
163 				  : win->_nc_bkgd);
164 		    }
165 		} else {
166 		    s = win->_line[row].text;
167 		}
168 	    } else {
169 		if ((s = typeMalloc(NCURSES_CH_T, ToCols + 1)) == 0)
170 		    returnCode(cleanup_lines(new_lines, row));
171 		for (col = 0; col <= ToCols; ++col)
172 		    s[col] = win->_nc_bkgd;
173 	    }
174 	} else {
175 	    s = &pline[win->_pary + row].text[win->_parx];
176 	}
177 
178 	if_USE_SCROLL_HINTS(new_lines[row].oldindex = row);
179 	if (row <= size_y) {
180 	    new_lines[row].firstchar = win->_line[row].firstchar;
181 	    new_lines[row].lastchar = win->_line[row].lastchar;
182 	}
183 	if ((ToCols != size_x) || (row > size_y)) {
184 	    if (end >= begin) {	/* growing */
185 		if (new_lines[row].firstchar < begin)
186 		    new_lines[row].firstchar = begin;
187 	    } else {		/* shrinking */
188 		new_lines[row].firstchar = 0;
189 	    }
190 	    new_lines[row].lastchar = ToCols;
191 	}
192 	new_lines[row].text = s;
193     }
194 
195     /*
196      * Dispose of unwanted memory.
197      */
198     if (!(win->_flags & _SUBWIN)) {
199 	if (ToCols == size_x) {
200 	    for (row = ToLines + 1; row <= size_y; row++) {
201 		free(win->_line[row].text);
202 	    }
203 	} else {
204 	    for (row = 0; row <= size_y; row++) {
205 		free(win->_line[row].text);
206 	    }
207 	}
208     }
209 
210     free(win->_line);
211     win->_line = new_lines;
212 
213     /*
214      * Finally, adjust the parameters showing screen size and cursor
215      * position:
216      */
217     win->_maxx = ToCols;
218     win->_maxy = ToLines;
219 
220     if (win->_regtop > win->_maxy)
221 	win->_regtop = win->_maxy;
222     if (win->_regbottom > win->_maxy
223 	|| win->_regbottom == size_y)
224 	win->_regbottom = win->_maxy;
225 
226     if (win->_curx > win->_maxx)
227 	win->_curx = win->_maxx;
228     if (win->_cury > win->_maxy)
229 	win->_cury = win->_maxy;
230 
231     /*
232      * Check for subwindows of this one, and readjust pointers to our text,
233      * if needed.
234      */
235     repair_subwindows(win);
236 
237 #ifdef TRACE
238     TR(TRACE_UPDATE, ("...beg (%ld, %ld), max(%ld,%ld), reg(%ld,%ld)",
239 		      (long) win->_begy, (long) win->_begx,
240 		      (long) win->_maxy, (long) win->_maxx,
241 		      (long) win->_regtop, (long) win->_regbottom));
242     if (USE_TRACEF(TRACE_UPDATE)) {
243 	_tracedump("...after:", win);
244 	_nc_unlock_global(tracef);
245     }
246 #endif
247     returnCode(OK);
248 }
249