xref: /netbsd-src/lib/libcurses/ripoffline.c (revision 777518dc503045cf143b17e649c348f42ba438d6)
1 /*	$NetBSD: ripoffline.c,v 1.7 2022/01/01 08:34:35 msaitoh 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 1.7 2022/01/01 08:34:35 msaitoh 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
ripoffline(int line,int (* init)(WINDOW *,int))53 ripoffline(int line, int (*init)(WINDOW *, int))
54 {
55 
56 	__CTRACE(__CTRACE_WINDOW, "ripoffline: %d\n", line);
57 
58 	if (nrips >= MAX_RIPS || init == NULL)
59 		return ERR; /* This makes sense, but not standards compliant. */
60 	if (line == 0)
61 		return OK;
62 	ripoffs[nrips].nlines = line < 0 ? -1 : 1;
63 	ripoffs[nrips++].init = init;
64 	return OK;
65 }
66 
67 /*
68  * __rippedlines --
69  *	Returns the number of ripped lines from the screen.
70  */
71 int
__rippedlines(const SCREEN * screen,int line)72 __rippedlines(const SCREEN *screen, int line)
73 {
74 	const struct __ripoff *rip;
75 	int i, n;
76 
77 	n = 0;
78 	for (i = 0, rip = screen->ripped; i < screen->nripped; i++, rip++) {
79 		if (line < 1 && rip->nlines < 0)
80 			n += -rip->nlines;
81 		else if (line > 0 && rip->nlines > 0)
82 			n += rip->nlines;
83 	}
84 	return n;
85 }
86 
87 /*
88  * __ripoffscreen --
89  *	Rips lines from the screen by creating a WINDOW per ripoffline call.
90  *	Although the POSIX API only allows for one line WINDOWS to be created,
91  *	this implementation allows for N lines if needed.
92  */
93 int
__ripoffscreen(SCREEN * screen)94 __ripoffscreen(SCREEN *screen)
95 {
96 	int i, nlines, rbot, rtop;
97 	const struct ripoff *srip;
98 	struct __ripoff *rip;
99 	WINDOW *w;
100 
101 	rip = screen->ripped;
102 	rbot = LINES;
103 	rtop = 0;
104 	for (i = 0, srip = ripoffs; i < nrips; i++, srip++) {
105 		if (srip->nlines == 0)
106 			continue;
107 		nlines = srip->nlines < 0 ? -srip->nlines : srip->nlines;
108 		w = __newwin(screen, nlines, 0,
109 		    srip->nlines < 0 ? rbot - nlines : rtop,
110 		    0, FALSE, FALSE);
111 		if (w != NULL) {
112 			rip->win = w;
113 			rip->nlines = srip->nlines;
114 			rip++;
115 			screen->nripped++;
116 			if (srip->nlines > 0)
117 				rtop += nlines;
118 			else
119 				rbot -= nlines;
120 		}
121 		if (srip->init(w, COLS) == ERR)
122 			return ERR;
123 #ifdef DEBUG
124 		if (w != NULL)
125 			__CTRACE(__CTRACE_WINDOW,
126 			    "newterm: %p ripped %d line(s) from the %s\n",
127 			    w, 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 int
__ripoffresize(SCREEN * screen)140 __ripoffresize(SCREEN *screen)
141 {
142 	int rbot = screen->LINES, i, nlines, ret = OK;
143 	struct __ripoff *rip;
144 
145 	for (i = 0, rip = screen->ripped; i < screen->nripped; i++, rip++) {
146 		if (rip->nlines == 0)
147 			continue;
148 		nlines = rip->nlines < 0 ? -rip->nlines : rip->nlines;
149 		if (wresize(rip->win, nlines, screen->COLS) == ERR)
150 			ret = ERR;
151 		if (rip->nlines < 0) {
152 			/* Reposition the lower windows. */
153 			if (mvwin(rip->win, rbot + rip->nlines, 0) == ERR)
154 				ret = ERR;
155 			else
156 				rbot += rip->nlines;
157 		}
158 	}
159 
160 	return ret;
161 }
162 
163 /*
164  *  __ripofftouch --
165  *	Displays the ripped off lines from initscr.
166  */
167 void
__ripofftouch(SCREEN * screen)168 __ripofftouch(SCREEN *screen)
169 {
170 	int i;
171 	struct __ripoff *rip;
172 
173 	for (i = 0, rip = screen->ripped; i < screen->nripped; i++, rip++) {
174 		touchwin(rip->win);
175 		wnoutrefresh(rip->win);
176 	}
177 }
178 
179 /*
180  * __unripoffline --
181  *	Used by __slk_init to remove the ripoffline reservation it made
182  *	because the terminal natively supports soft label keys.
183  */
184 int
__unripoffline(int (* init)(WINDOW *,int))185 __unripoffline(int (*init)(WINDOW *, int))
186 {
187 	struct ripoff *rip;
188 	int i, unripped = 0;
189 
190 	for (i = 0, rip = ripoffs; i < nrips; i++, rip++) {
191 		if (rip->init == init) {
192 			rip->nlines = 0;
193 			unripped++;
194 		}
195 	}
196 	return unripped;
197 }
198