1 /*
2 * Copyright (c) 1983, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * %sccs.include.redist.c%
6 */
7
8 #ifndef lint
9 static char sccsid[] = "@(#)display.c 8.1 (Berkeley) 06/06/93";
10 #endif /* not lint */
11
12 /*
13 * The window 'manager', initializes curses and handles the actual
14 * displaying of text
15 */
16 #include "talk.h"
17
18 xwin_t my_win;
19 xwin_t his_win;
20 WINDOW *line_win;
21
22 int curses_initialized = 0;
23
24 /*
25 * max HAS to be a function, it is called with
26 * a argument of the form --foo at least once.
27 */
max(a,b)28 max(a,b)
29 int a, b;
30 {
31
32 return (a > b ? a : b);
33 }
34
35 /*
36 * Display some text on somebody's window, processing some control
37 * characters while we are at it.
38 */
display(win,text,size)39 display(win, text, size)
40 register xwin_t *win;
41 register char *text;
42 int size;
43 {
44 register int i;
45 char cch;
46
47 for (i = 0; i < size; i++) {
48 if (*text == '\n') {
49 xscroll(win, 0);
50 text++;
51 continue;
52 }
53 /* erase character */
54 if (*text == win->cerase) {
55 wmove(win->x_win, win->x_line, max(--win->x_col, 0));
56 getyx(win->x_win, win->x_line, win->x_col);
57 waddch(win->x_win, ' ');
58 wmove(win->x_win, win->x_line, win->x_col);
59 getyx(win->x_win, win->x_line, win->x_col);
60 text++;
61 continue;
62 }
63 /*
64 * On word erase search backwards until we find
65 * the beginning of a word or the beginning of
66 * the line.
67 */
68 if (*text == win->werase) {
69 int endcol, xcol, i, c;
70
71 endcol = win->x_col;
72 xcol = endcol - 1;
73 while (xcol >= 0) {
74 c = readwin(win->x_win, win->x_line, xcol);
75 if (c != ' ')
76 break;
77 xcol--;
78 }
79 while (xcol >= 0) {
80 c = readwin(win->x_win, win->x_line, xcol);
81 if (c == ' ')
82 break;
83 xcol--;
84 }
85 wmove(win->x_win, win->x_line, xcol + 1);
86 for (i = xcol + 1; i < endcol; i++)
87 waddch(win->x_win, ' ');
88 wmove(win->x_win, win->x_line, xcol + 1);
89 getyx(win->x_win, win->x_line, win->x_col);
90 text++;
91 continue;
92 }
93 /* line kill */
94 if (*text == win->kill) {
95 wmove(win->x_win, win->x_line, 0);
96 wclrtoeol(win->x_win);
97 getyx(win->x_win, win->x_line, win->x_col);
98 text++;
99 continue;
100 }
101 if (*text == '\f') {
102 if (win == &my_win)
103 wrefresh(curscr);
104 text++;
105 continue;
106 }
107 if (win->x_col == COLS-1) {
108 /* check for wraparound */
109 xscroll(win, 0);
110 }
111 if (*text < ' ' && *text != '\t') {
112 waddch(win->x_win, '^');
113 getyx(win->x_win, win->x_line, win->x_col);
114 if (win->x_col == COLS-1) /* check for wraparound */
115 xscroll(win, 0);
116 cch = (*text & 63) + 64;
117 waddch(win->x_win, cch);
118 } else
119 waddch(win->x_win, *text);
120 getyx(win->x_win, win->x_line, win->x_col);
121 text++;
122 }
123 wrefresh(win->x_win);
124 }
125
126 /*
127 * Read the character at the indicated position in win
128 */
readwin(win,line,col)129 readwin(win, line, col)
130 WINDOW *win;
131 {
132 int oldline, oldcol;
133 register int c;
134
135 getyx(win, oldline, oldcol);
136 wmove(win, line, col);
137 c = winch(win);
138 wmove(win, oldline, oldcol);
139 return (c);
140 }
141
142 /*
143 * Scroll a window, blanking out the line following the current line
144 * so that the current position is obvious
145 */
xscroll(win,flag)146 xscroll(win, flag)
147 register xwin_t *win;
148 int flag;
149 {
150
151 if (flag == -1) {
152 wmove(win->x_win, 0, 0);
153 win->x_line = 0;
154 win->x_col = 0;
155 return;
156 }
157 win->x_line = (win->x_line + 1) % win->x_nlines;
158 win->x_col = 0;
159 wmove(win->x_win, win->x_line, win->x_col);
160 wclrtoeol(win->x_win);
161 wmove(win->x_win, (win->x_line + 1) % win->x_nlines, win->x_col);
162 wclrtoeol(win->x_win);
163 wmove(win->x_win, win->x_line, win->x_col);
164 }
165