xref: /titanic_44/usr/src/lib/libbc/libc/stdio/common/setbuffer.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 1986 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*
28  * University Copyright- Copyright (c) 1982, 1986, 1988
29  * The Regents of the University of California
30  * All Rights Reserved
31  *
32  * University Acknowledgment- Portions of this document are derived from
33  * software developed by the University of California, Berkeley, and its
34  * contributors.
35  */
36 
37 #pragma ident	"%Z%%M%	%I%	%E% SMI"
38  /* from UCB 4.2 83/02/27 */
39 
40 #include <stdio.h>
41 
42 extern void free();
43 extern int isatty();
44 extern unsigned char (*_smbuf)[_SBFSIZ];
45 extern void _getsmbuf();
46 
47 void
48 setbuffer(iop, buf, size)
49 	register FILE *iop;
50 	char *buf;
51 	int size;
52 {
53 	register int fno = fileno(iop);  /* file number */
54 
55 	if (iop->_base != NULL && iop->_flag&_IOMYBUF)
56 		free((char *)iop->_base);
57 	iop->_flag &= ~(_IOMYBUF|_IONBF|_IOLBF);
58 	if ((iop->_base = (unsigned char *)buf) == NULL) {
59 		iop->_flag |= _IONBF; /* file unbuffered except in fastio */
60 		/* use small buffers reserved for this */
61 		iop->_base = _smbuf[fno];
62 		iop->_bufsiz = _SBFSIZ;
63 	} else {
64 		/* regular buffered I/O, specified buffer size */
65 		if (size <= 0)
66 			return;
67 		iop->_bufsiz = size;
68 	}
69 	iop->_ptr = iop->_base;
70 	iop->_cnt = 0;
71 }
72 
73 /*
74  * set line buffering
75  */
76 setlinebuf(iop)
77 	register FILE *iop;
78 {
79 	register unsigned char *buf;
80 	extern char *malloc();
81 
82 	fflush(iop);
83 	setbuffer(iop, (unsigned char *)NULL, 0);
84 	buf = (unsigned char *)malloc(128);
85 	if (buf != NULL) {
86 		setbuffer(iop, buf, 128);
87 		iop->_flag |= _IOLBF|_IOMYBUF;
88 	}
89 }
90