xref: /netbsd-src/lib/libcurses/ripoffline.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: ripoffline.c,v 1.3 2017/01/24 17:27:30 roy Exp $	*/
2 
3 /*-
4  * Copyright (c) 2017 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Roy Marples.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __RCSID("$NetBSD: ripoffline.c,v 1.3 2017/01/24 17:27:30 roy Exp $");
35 #endif				/* not lint */
36 
37 #include "curses.h"
38 #include "curses_private.h"
39 
40 /* List of ripoffline calls */
41 static struct ripoff {
42 	int	nlines;
43 	int	(*init)(WINDOW *, int);
44 } ripoffs[MAX_RIPS];
45 static int nrips;
46 
47 /*
48  * ripoffline --
49  *	Ripoff a line from the top of bottom of stdscr.
50  *	Must be called before initscr or newterm.
51  */
52 int
53 ripoffline(int line, int (*init)(WINDOW *, int))
54 {
55 
56 #ifdef DEBUG
57 	__CTRACE(__CTRACE_SCREEN, "ripoffline: %d\n", line);
58 #endif
59 
60 	if (nrips >= MAX_RIPS || init == NULL)
61 		return ERR; /* This makes sense, but not standards compliant. */
62 	if (line == 0)
63 		return OK;
64 	ripoffs[nrips].nlines = line < 0 ? -1 : 1;
65 	ripoffs[nrips++].init = init;
66 	return OK;
67 }
68 
69 /*
70  * __rippedlines --
71  *	Returns the number of ripped lines from the screen.
72  */
73 int
74 __rippedlines(const SCREEN *screen)
75 {
76 	const struct __ripoff *rip;
77 	int i, n;
78 
79 	n = 0;
80 	for (i = 0, rip = screen->ripped; i < screen->nripped; i++, rip++) {
81 		if (rip->nlines < 0)
82 			n += -rip->nlines;
83 		else
84 			n += rip->nlines;
85 	}
86 	return n;
87 }
88 
89 /*
90  * __ripoffscreen --
91  *	Rips lines from the screen by creating a WINDOW per ripoffline call.
92  *	Although the POSIX API only allows for one line WINDOWS to be created,
93  *	this implemenation allows for N lines if needed.
94  */
95 int
96 __ripoffscreen(SCREEN *screen, int *rtop)
97 {
98 	int i, nlines;
99 	const struct ripoff *srip;
100 	struct __ripoff *rip;
101 	WINDOW *w;
102 
103 	*rtop = 0;
104 	rip = screen->ripped;
105 	for (i = 0, srip = ripoffs; i < nrips; i++, srip++) {
106 		if (srip->nlines == 0)
107 			continue;
108 		nlines = srip->nlines < 0 ? -srip->nlines : srip->nlines;
109 		w = __newwin(screen, nlines, 0,
110 		    srip->nlines < 0 ? LINES - nlines : *rtop,
111 		    0, FALSE);
112 		if (w != NULL) {
113 			rip->win = w;
114 			rip->nlines = srip->nlines;
115 			rip++;
116 			screen->nripped++;
117 			if (rip->nlines > 0)
118 				(*rtop) += rip->nlines;
119 			LINES -= nlines;
120 		}
121 		if (srip->init(w, COLS) == ERR)
122 			return ERR;
123 #ifdef DEBUG
124 		if (w != NULL)
125 			__CTRACE(__CTRACE_SCREEN,
126 			    "newterm: ripped %d lines from the %s\n",
127 			    nlines, srip->nlines < 0 ? "bottom" : "top");
128 #endif
129 	}
130 	nrips = 0; /* Reset the stack. */
131 	return OK;
132 }
133 
134 /*
135  * __ripoffresize --
136  *	Called from resizeterm to ensure the ripped off lines are correctly
137  *	placed and refreshed.
138  */
139 void
140 __ripoffresize(SCREEN *screen)
141 {
142 	int rbot = screen->LINES, i;
143 	struct __ripoff *rip;
144 
145 	for (i = 0, rip = screen->ripped; i < screen->nripped; i++, rip++) {
146 		if (rip->nlines > 0)
147 			touchwin(rip->win);
148 		else {
149 			/* Reposition the lower windows. */
150 			mvwin(rip->win, rbot + rip->nlines, 0);
151 			rbot += rip->nlines;
152 		}
153 		wnoutrefresh(rip->win);
154 	}
155 }
156 
157 /*
158  * __unripoffline --
159  *	Used by __slk_init to remove the ripoffline reservation it made
160  *	because the terminal natively supports soft label keys.
161  */
162 int
163 __unripoffline(int (*init)(WINDOW *, int))
164 {
165 	struct ripoff *rip;
166 	int i, unripped = 0;
167 
168 	for (i = 0, rip = ripoffs; i < nrips; i++, rip++) {
169 		if (rip->init == init) {
170 			rip->nlines = 0;
171 			unripped++;
172 		}
173 	}
174 	return unripped;
175 }
176