Generally use NULL instead of explicitly casting 0 to some pointer type (part2).
[dragonfly.git] / usr.bin / window / ttoutput.c
blob111e0ac7800ad0a4c6b6a14cf28a88ebdeb445c4
1 /*
2 * Copyright (c) 1983, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
6 * Edward Wang at The University of California, Berkeley.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
36 * @(#)ttoutput.c 8.1 (Berkeley) 6/6/93
37 * $FreeBSD: src/usr.bin/window/ttoutput.c,v 1.1.1.1.14.2 2001/05/17 09:45:01 obrien Exp $
38 * $DragonFly: src/usr.bin/window/ttoutput.c,v 1.2 2003/06/17 04:29:34 dillon Exp $
41 #include <errno.h>
42 #include <string.h>
44 #include "ww.h"
45 #include "tt.h"
48 * Buffered output package.
49 * We need this because stdio fails on non-blocking writes.
52 ttflush()
54 register char *p;
55 register n = tt_obp - tt_ob;
57 if (n == 0)
58 return;
59 if (tt.tt_checksum)
60 (*tt.tt_checksum)(tt_ob, n);
61 if (tt.tt_flush) {
62 (*tt.tt_flush)();
63 return;
65 wwnflush++;
66 for (p = tt_ob; p < tt_obp;) {
67 wwnwr++;
68 n = write(1, p, tt_obp - p);
69 if (n < 0) {
70 wwnwre++;
71 if (errno != EWOULDBLOCK) {
72 /* can't deal with this */
73 p = tt_obp;
75 } else if (n == 0) {
76 /* what to do? */
77 wwnwrz++;
78 } else {
79 wwnwrc += n;
80 p += n;
83 tt_obp = tt_ob;
86 ttputs(s)
87 register char *s;
89 while (*s)
90 ttputc(*s++);
93 ttwrite(s, n)
94 register char *s;
95 register n;
97 switch (n) {
98 case 0:
99 break;
100 case 1:
101 ttputc(*s);
102 break;
103 case 2:
104 if (tt_obe - tt_obp < 2)
105 ttflush();
106 *tt_obp++ = *s++;
107 *tt_obp++ = *s;
108 break;
109 case 3:
110 if (tt_obe - tt_obp < 3)
111 ttflush();
112 *tt_obp++ = *s++;
113 *tt_obp++ = *s++;
114 *tt_obp++ = *s;
115 break;
116 case 4:
117 if (tt_obe - tt_obp < 4)
118 ttflush();
119 *tt_obp++ = *s++;
120 *tt_obp++ = *s++;
121 *tt_obp++ = *s++;
122 *tt_obp++ = *s;
123 break;
124 case 5:
125 if (tt_obe - tt_obp < 5)
126 ttflush();
127 *tt_obp++ = *s++;
128 *tt_obp++ = *s++;
129 *tt_obp++ = *s++;
130 *tt_obp++ = *s++;
131 *tt_obp++ = *s;
132 break;
133 default:
134 while (n > 0) {
135 register m;
137 while ((m = tt_obe - tt_obp) == 0)
138 ttflush();
139 if ((m = tt_obe - tt_obp) > n)
140 m = n;
141 bcopy(s, tt_obp, m);
142 tt_obp += m;
143 s += m;
144 n -= m;