xref: /illumos-gate/usr/src/lib/libeti/panel/common/misc.c (revision 581cede61ac9c14d8d4ea452562a567189eead78)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*	Copyright (c) 1988 AT&T	*/
23 /*	  All Rights Reserved  	*/
24 
25 
26 /*
27  *      Copyright (c) 1997, by Sun Microsystems, Inc.
28  *      All rights reserved.
29  */
30 
31 /* A panels subsystem built on curses--Miscellaneous routines */
32 
33 #pragma ident	"%Z%%M%	%I%	%E% SMI"	/* SVr4.0 1.4	*/
34 
35 /*LINTLIBRARY*/
36 
37 #include <sys/types.h>
38 #include <stdlib.h>
39 #include <curses.h>
40 #include "private.h"
41 
42 PANEL	*_Bottom_panel;
43 PANEL	*_Top_panel;
44 int	_Panel_cnt;
45 
46 static	_obscured_list	*_Free_list;
47 static int	_Free_list_cnt;
48 
49 
50 /* panel_window - Return the window pointer */
51 WINDOW *
52 panel_window(PANEL *panel)
53 {
54 	return (panel ? panel -> win : 0);
55 }
56 
57 /* panel_userptr - Return the user pointer */
58 char *
59 panel_userptr(PANEL *panel)
60 {
61 	return (panel ? panel -> user : 0);
62 }
63 
64 /* set_panel_userptr - set the user pointer */
65 int
66 set_panel_userptr(PANEL *panel, char *ptr)
67 {
68 	if (panel) {
69 		panel -> user = ptr;
70 		return (OK);
71 	} else
72 		return (ERR);
73 }
74 
75 /*
76  * panel_above - Return the panel above the
77  * given panel (or the bottom panel in 0)
78  */
79 PANEL *
80 panel_above(PANEL *panel)
81 {
82 
83 	if (!panel)
84 		return (_Bottom_panel);
85 
86 	return ((panel == panel -> below) ? ((PANEL *) 0) : panel -> above);
87 }
88 
89 
90 /*
91  * panel_below - Return the panel below the
92  * given panel (or the top panel in 0)
93  */
94 PANEL *
95 panel_below(PANEL *panel)
96 {
97 
98 	if (!panel)
99 		return (_Top_panel);
100 
101 	return ((panel == panel -> below) ? ((PANEL *) 0) : panel -> below);
102 }
103 
104 /* panel_hidden - Return TRUE if the panel is hidden, FALSE if not.  */
105 int
106 panel_hidden(PANEL *panel)
107 {
108 	return ((!panel || (panel != panel -> below)) ? FALSE : TRUE);
109 }
110 
111 /* _get_overlap - Get an overlap node from the free list. */
112 static _obscured_list *
113 _get_overlap(void)
114 {
115 	_obscured_list	*overlap;
116 
117 	if (_Free_list_cnt-- > 0) {
118 		overlap = _Free_list;
119 		_Free_list = _Free_list -> next;
120 	} else {
121 		_Free_list_cnt = 0;
122 		overlap = 0;
123 	}
124 
125 	return (overlap);
126 }
127 
128 
129 /*
130  * _unlink_obs - Find the obscured node, if any,
131  * in the first panel which refers the second panel.
132  */
133 _obscured_list *
134 _unlink_obs(PANEL *pnl, PANEL *panel)
135 {
136 	_obscured_list	*obs;
137 	_obscured_list	*prev_obs;
138 
139 	if (!pnl -> obscured || !_panels_intersect(pnl, panel))
140 		return ((_obscured_list *) 0);
141 
142 	obs = pnl -> obscured;
143 	do {
144 		prev_obs = obs;
145 		obs = obs -> next;
146 	}
147 	while (obs->panel_p != panel && obs != pnl->obscured);
148 	if (obs -> panel_p != panel) {
149 #ifdef DEBUG
150 		fprintf(stderr, "_unlink_obs:  Obscured panel lost\n");
151 #endif
152 		return ((_obscured_list *) 0);
153 	}
154 
155 	if (obs == prev_obs)
156 		pnl -> obscured = 0;
157 	else {
158 		prev_obs -> next = obs -> next;
159 		if (obs == pnl -> obscured)
160 			pnl -> obscured = prev_obs;
161 	}
162 	return (obs);
163 }
164 
165 /*
166  * add_obs - Add an obscured node to a panel, ensuring
167  * that the obscured list is ordered from top to bottom.
168  */
169 static void
170 add_obs(PANEL *panel, _obscured_list *obs)
171 {
172 	PANEL		*pnl;
173 	_obscured_list	*curr_obs;
174 	_obscured_list	*prev_obs;
175 
176 	if ((prev_obs = panel -> obscured) == 0) {
177 		panel -> obscured = obs -> next = obs;
178 		return;
179 	}
180 
181 	curr_obs = prev_obs -> next;
182 
183 	for (pnl = _Top_panel; pnl != panel; pnl = pnl->below) {
184 		if (curr_obs -> panel_p == pnl) {
185 			prev_obs = curr_obs;
186 			curr_obs = curr_obs -> next;
187 			if (prev_obs == panel -> obscured) {
188 				panel -> obscured = obs;
189 				break;
190 			}
191 		}
192 	}
193 
194 	obs -> next = curr_obs;
195 	prev_obs -> next = obs;
196 }
197 
198 
199 /*
200  *  _intersect_panel
201  * Create an obscured node for each panel that the given panel intersects.
202  * The overlap record is always attached to the panel which is covered up.
203  *
204  * This routine assumes that _alloc_overlap() has been called to ensure
205  * that there are enough overlap nodes to satisfy the requests.
206  */
207 void
208 _intersect_panel(PANEL *panel)
209 {
210 	PANEL		*pnl;
211 	_obscured_list	*obs;
212 	int		above_panel;
213 
214 	above_panel = FALSE;
215 
216 	for (pnl = _Bottom_panel; pnl; pnl = pnl -> above) {
217 		if (pnl == panel) {
218 			above_panel = TRUE;
219 			continue;
220 		}
221 
222 		if (!_panels_intersect(pnl, panel))
223 			continue;	/* no overlap */
224 
225 		obs = _get_overlap();
226 		obs->start = (panel->wstarty >= pnl->wstarty) ?
227 				panel->wstarty : pnl->wstarty;
228 		obs->end = (panel->wendy <= pnl->wendy) ?
229 				panel->wendy : pnl->wendy;
230 
231 		if (above_panel) {
232 			obs -> panel_p = pnl;
233 			if (panel -> obscured) {
234 				obs -> next = panel -> obscured -> next;
235 				panel -> obscured -> next = obs;
236 			} else
237 				obs -> next = panel -> obscured = obs;
238 		} else {
239 			obs -> panel_p = panel;
240 			add_obs(pnl, obs);
241 		}
242 
243 	}
244 }
245 
246 /*
247  *  _alloc_overlap
248  * Create enough obscured nodes to record all overlaps of a given
249  * panel.  The obscured nodes must be pre-allocated by this routine
250  * to preserve the integrity of the pile during move.
251  * If the move operation fails, the pile is supposed to remain
252  * unchanged.  If the obscured nodes are not allocated in advance,
253  * then an allocation failure in the middle of a move could
254  * leave the pile in a corrupted state with possibly no way to
255  * restore the pile to its original state.
256  *
257  * The cnt parameter is the(worst case) number of overlap nodes which
258  * are required to satisfy any request.  Return 0 on error, else non-zero
259  */
260 int
261 _alloc_overlap(int cnt)
262 {
263 	_obscured_list	*overlap;
264 	int		i;
265 
266 	for (i = cnt-_Free_list_cnt; i > 0; i--) {
267 		if (!(overlap = (_obscured_list *)
268 		    malloc(sizeof (_obscured_list))))
269 			return (0);
270 
271 		overlap -> next = _Free_list;
272 		_Free_list = overlap;
273 		_Free_list_cnt++;
274 	}
275 
276 	return (1);
277 }
278 
279 
280 /*
281  * _free_overlap - Free a single overlap node.  Don't
282  * really free it; just save it on a list.
283  */
284 void
285 _free_overlap(_obscured_list *overlap)
286 {
287 	overlap -> next = _Free_list;
288 	_Free_list = overlap;
289 	_Free_list_cnt++;
290 }
291