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scroll.c revision 1.27.4.1 
      1 /*	$NetBSD: scroll.c,v 1.27.4.1 2025/08/02 05:54:47 perseant Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1981, 1993, 1994
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 #ifndef lint
     34 #if 0
     35 static char sccsid[] = "@(#)scroll.c	8.3 (Berkeley) 5/4/94";
     36 #else
     37 __RCSID("$NetBSD: scroll.c,v 1.27.4.1 2025/08/02 05:54:47 perseant Exp $");
     38 #endif
     39 #endif				/* not lint */
     40 
     41 #include "curses.h"
     42 #include "curses_private.h"
     43 
     44 /*
     45  * scroll --
     46  *	Scroll the window up a line.
     47  */
     48 int
     49 scroll(WINDOW *win)
     50 {
     51 
     52 	return wscrl(win, 1);
     53 }
     54 
     55 #ifndef _CURSES_USE_MACROS
     56 
     57 /*
     58  * scrl --
     59  *	Scroll stdscr n lines - up if n is positive, down if n is negative.
     60  */
     61 int
     62 scrl(int nlines)
     63 {
     64 
     65 	return wscrl(stdscr, nlines);
     66 }
     67 
     68 /*
     69  * setscrreg --
     70  *	Set the top and bottom of the scrolling region for stdscr.
     71  */
     72 int
     73 setscrreg(int top, int bottom)
     74 {
     75 
     76 	return wsetscrreg(stdscr, top, bottom);
     77 }
     78 
     79 /*
     80  * getscrreg --
     81  *	Get the top and bottom of the scrolling region for stdscr.
     82  */
     83 int
     84 getscrreg(int *top, int *bottom)
     85 {
     86 
     87 	return wgetscrreg(stdscr, top, bottom);
     88 }
     89 
     90 #endif
     91 
     92 /*
     93  * wscrl --
     94  *	Scroll a window n lines - up if n is positive, down if n is negative.
     95  */
     96 int
     97 wscrl(WINDOW *win, int nlines)
     98 {
     99 	int     oy, ox;
    100 
    101 	__CTRACE(__CTRACE_WINDOW, "wscrl: (%p) lines=%d\n", win, nlines);
    102 
    103 	if (__predict_false(win == NULL))
    104 		return ERR;
    105 
    106 	if (!(win->flags & __SCROLLOK))
    107 		return ERR;
    108 	if (!nlines)
    109 		return OK;
    110 
    111 	getyx(win, oy, ox);
    112 	__CTRACE(__CTRACE_WINDOW, "wscrl: y=%d\n", oy);
    113 	wmove(win, win->scr_t, 1);
    114 	winsdelln(win, 0 - nlines);
    115 	wmove(win, oy, ox);
    116 
    117 	if (win == curscr) {
    118 		__cputchar('\n');
    119 		if (!__NONL)
    120 			win->curx = 0;
    121 		__CTRACE(__CTRACE_WINDOW, "scroll: win == curscr\n");
    122 	}
    123 	return OK;
    124 }
    125 
    126 /*
    127  * wsetscrreg --
    128  *	Set the top and bottom of the scrolling region for win.
    129  */
    130 int
    131 wsetscrreg(WINDOW *win, int top, int bottom)
    132 {
    133 	if (__predict_false(win == NULL))
    134 		return ERR;
    135 
    136 	if (top < 0 || bottom >= win->maxy || bottom - top < 1)
    137 		return ERR;
    138 	win->scr_t = top;
    139 	win->scr_b = bottom;
    140 	return OK;
    141 }
    142 
    143 /*
    144  * wgetscrreg --
    145  *	Get the top and bottom of the scrolling region for win.
    146  */
    147 int
    148 wgetscrreg(WINDOW *win, int *top, int *bottom)
    149 {
    150 	if (__predict_false(win == NULL))
    151 		return ERR;
    152 
    153 	*top = win->scr_t;
    154 	*bottom = win->scr_b;
    155 	return OK;
    156 }
    157 
    158 /*
    159  * has_ic --
    160  *	Does the terminal have insert- and delete-character?
    161  */
    162 bool
    163 has_ic(void)
    164 {
    165 
    166 	if (insert_character != NULL && delete_character != NULL)
    167 		return true;
    168 	else
    169 		return false;
    170 }
    171 
    172 /*
    173  * has_ic --
    174  *	Does the terminal have insert- and delete-line?
    175  */
    176 bool
    177 has_il(void)
    178 {
    179 	if (insert_line !=NULL && delete_line != NULL)
    180 		return true;
    181 	else
    182 		return false;
    183 }
    184