xref: /original-bsd/usr.bin/window/wwinschar.c (revision c3e32dec)
1 /*
2  * Copyright (c) 1983, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Edward Wang at The University of California, Berkeley.
7  *
8  * %sccs.include.redist.c%
9  */
10 
11 #ifndef lint
12 static char sccsid[] = "@(#)wwinschar.c	8.1 (Berkeley) 06/06/93";
13 #endif /* not lint */
14 
15 #include "ww.h"
16 #include "tt.h"
17 
18 wwinschar(w, row, col, c, m)
19 register struct ww *w;
20 char c, m;
21 {
22 	register i;
23 	int nvis;
24 	short x = c | m << WWC_MSHIFT;
25 
26 	/*
27 	 * First, shift the line.
28 	 */
29 	{
30 		register union ww_char *p, *q;
31 
32 		p = &w->ww_buf[row][w->ww_b.r];
33 		q = p - 1;
34 		for (i = w->ww_b.r - col; --i > 0;)
35 			*--p = *--q;
36 		q->c_w = x;
37 	}
38 
39 	/*
40 	 * If can't see it, just return.
41 	 */
42 	if (row < w->ww_i.t || row >= w->ww_i.b
43 	    || w->ww_i.r <= 0 || w->ww_i.r <= col)
44 		return;
45 
46 	if (col < w->ww_i.l)
47 		col = w->ww_i.l;
48 
49 	/*
50 	 * Now find out how much is actually changed, and fix wwns.
51 	 */
52 	{
53 		register union ww_char *buf;
54 		register char *win;
55 		register union ww_char *ns;
56 		register char *smap;
57 		char touched;
58 
59 		nvis = 0;
60 		smap = &wwsmap[row][col];
61 		for (i = col; i < w->ww_i.r && *smap++ != w->ww_index; i++)
62 			;
63 		if (i >= w->ww_i.r)
64 			return;
65 		col = i;
66 		buf = w->ww_buf[row];
67 		win = w->ww_win[row];
68 		ns = wwns[row];
69 		smap = &wwsmap[row][i];
70 		touched = wwtouched[row];
71 		for (; i < w->ww_i.r; i++) {
72 			if (*smap++ != w->ww_index)
73 				continue;
74 			touched |= WWU_TOUCHED;
75 			if (win[i])
76 				ns[i].c_w =
77 					buf[i].c_w ^ win[i] << WWC_MSHIFT;
78 			else {
79 				nvis++;
80 				ns[i] = buf[i];
81 			}
82 		}
83 		wwtouched[row] = touched;
84 	}
85 
86 	/*
87 	 * Can/Should we use delete character?
88 	 */
89 	if ((tt.tt_inschar || tt.tt_insspace) && nvis > (wwncol - col) / 2) {
90 		register union ww_char *p, *q;
91 
92 		if (tt.tt_inschar)
93 			xxinschar(row, col, c, m);
94 		else {
95 			xxinsspace(row, col);
96 			x = ' ';
97 		}
98 		p = &wwos[row][wwncol];
99 		q = p - 1;
100 		for (i = wwncol - col; --i > 0;)
101 			*--p = *--q;
102 		q->c_w = x;
103 	}
104 }
105