1 /*        $NetBSD: display.c,v 1.9 2011/09/06 18:32:03 joerg Exp $    */
2 
3 /*
4  * Copyright (c) 1983, 1993
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[] = "@(#)display.c   8.1 (Berkeley) 6/6/93";
36 #endif
37 __RCSID("$NetBSD: display.c,v 1.9 2011/09/06 18:32:03 joerg Exp $");
38 #endif /* not lint */
39 
40 /*
41  * The window 'manager', initializes curses and handles the actual
42  * displaying of text
43  */
44 #include "talk.h"
45 #include <ctype.h>
46 
47 xwin_t    my_win;
48 xwin_t    his_win;
49 WINDOW    *line_win;
50 
51 int       curses_initialized = 0;
52 
53 /*
54  * max HAS to be a function, it is called with
55  * a argument of the form --foo at least once.
56  */
57 int
max(int a,int b)58 max(int a, int b)
59 {
60 
61           return (a > b ? a : b);
62 }
63 
64 /*
65  * Display some text on somebody's window, processing some control
66  * characters while we are at it.
67  */
68 void
display(xwin_t * win,char * text,int size)69 display(xwin_t *win, char *text, int size)
70 {
71           int i;
72           char cch;
73 
74           for (i = 0; i < size; i++) {
75                     if (*text == '\n') {
76                               xscroll(win, 0);
77                               text++;
78                               continue;
79                     }
80                     /* erase character */
81                     if (*text == win->cerase) {
82                               wmove(win->x_win, win->x_line, max(--win->x_col, 0));
83                               getyx(win->x_win, win->x_line, win->x_col);
84                               waddch(win->x_win, ' ');
85                               wmove(win->x_win, win->x_line, win->x_col);
86                               getyx(win->x_win, win->x_line, win->x_col);
87                               text++;
88                               continue;
89                     }
90                     /*
91                      * On word erase search backwards until we find
92                      * the beginning of a word or the beginning of
93                      * the line.
94                      */
95                     if (*text == win->werase) {
96                               int endcol, xcol, j, c;
97 
98                               endcol = win->x_col;
99                               xcol = endcol - 1;
100                               while (xcol >= 0) {
101                                         c = readwin(win->x_win, win->x_line, xcol);
102                                         if (c != ' ')
103                                                   break;
104                                         xcol--;
105                               }
106                               while (xcol >= 0) {
107                                         c = readwin(win->x_win, win->x_line, xcol);
108                                         if (c == ' ')
109                                                   break;
110                                         xcol--;
111                               }
112                               wmove(win->x_win, win->x_line, xcol + 1);
113                               for (j = xcol + 1; j < endcol; j++)
114                                         waddch(win->x_win, ' ');
115                               wmove(win->x_win, win->x_line, xcol + 1);
116                               getyx(win->x_win, win->x_line, win->x_col);
117                               text++;
118                               continue;
119                     }
120                     /* line kill */
121                     if (*text == win->kill) {
122                               wmove(win->x_win, win->x_line, 0);
123                               wclrtoeol(win->x_win);
124                               getyx(win->x_win, win->x_line, win->x_col);
125                               text++;
126                               continue;
127                     }
128                     if (*text == '\f') {
129                               if (win == &my_win)
130                                         wrefresh(curscr);
131                               text++;
132                               continue;
133                     }
134                     if (*text == '\07') {
135                               beep();
136                               text++;
137                               continue;
138                     }
139                     if (win->x_col == COLS-1) {
140                               /* check for wraparound */
141                               xscroll(win, 0);
142                     }
143                     if ( !isprint((u_char)*text) && *text != '\t') {
144                               waddch(win->x_win, '^');
145                               getyx(win->x_win, win->x_line, win->x_col);
146                               if (win->x_col == COLS-1) /* check for wraparound */
147                                         xscroll(win, 0);
148                               cch = (*text & 63) + 64;
149                               waddch(win->x_win, cch);
150                     } else
151                               waddch(win->x_win, *text);
152                     getyx(win->x_win, win->x_line, win->x_col);
153                     text++;
154           }
155           wrefresh(win->x_win);
156 }
157 
158 /*
159  * Read the character at the indicated position in win
160  */
161 int
readwin(WINDOW * win,int line,int col)162 readwin(WINDOW *win, int line, int col)
163 {
164           int oldline, oldcol;
165           int c;
166 
167           getyx(win, oldline, oldcol);
168           wmove(win, line, col);
169           c = winch(win);
170           wmove(win, oldline, oldcol);
171           return (c);
172 }
173 
174 /*
175  * Scroll a window, blanking out the line following the current line
176  * so that the current position is obvious
177  */
178 void
xscroll(xwin_t * win,int flag)179 xscroll(xwin_t *win, int flag)
180 {
181 
182           if (flag == -1) {
183                     wmove(win->x_win, 0, 0);
184                     win->x_line = 0;
185                     win->x_col = 0;
186                     return;
187           }
188           win->x_line = (win->x_line + 1) % win->x_nlines;
189           win->x_col = 0;
190           wmove(win->x_win, win->x_line, win->x_col);
191           wclrtoeol(win->x_win);
192           wmove(win->x_win, (win->x_line + 1) % win->x_nlines, win->x_col);
193           wclrtoeol(win->x_win);
194           wmove(win->x_win, win->x_line, win->x_col);
195 }
196