xref: /dragonfly/usr.bin/window/ttoutput.c (revision c541a65d)
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  * 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.
23  *
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.
35  *
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 $
39  */
40 
41 #include <errno.h>
42 #include <string.h>
43 
44 #include "ww.h"
45 #include "tt.h"
46 
47 /*
48  * Buffered output package.
49  * We need this because stdio fails on non-blocking writes.
50  */
51 
52 ttflush()
53 {
54 	register char *p;
55 	register n = tt_obp - tt_ob;
56 
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;
64 	}
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;
74 			}
75 		} else if (n == 0) {
76 			/* what to do? */
77 			wwnwrz++;
78 		} else {
79 			wwnwrc += n;
80 			p += n;
81 		}
82 	}
83 	tt_obp = tt_ob;
84 }
85 
86 ttputs(s)
87 register char *s;
88 {
89 	while (*s)
90 		ttputc(*s++);
91 }
92 
93 ttwrite(s, n)
94 	register char *s;
95 	register n;
96 {
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;
136 
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;
145 		}
146 	}
147 }
148