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 (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 /* Copyright (c) 1988 AT&T */
28 /* All Rights Reserved */
29
30 /*
31 * Copyright 2020 Robert Mustacchi
32 * Copyright 2022 OmniOS Community Edition (OmniOSce) Association.
33 */
34
35 #include "lint.h"
36 #include "file64.h"
37 #include "mtlib.h"
38 #include <sys/types.h>
39 #include <errno.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <thread.h>
43 #include <synch.h>
44 #include "stdiom.h"
45
46 void
setbuf(FILE * iop,char * abuf)47 setbuf(FILE *iop, char *abuf)
48 {
49 Uchar *buf = (Uchar *)abuf;
50 int fno = _get_fd(iop); /* file number */
51 int size = BUFSIZ - _SMBFSZ;
52 Uchar *temp;
53 rmutex_t *lk;
54
55 FLOCKFILE(lk, iop);
56 if ((iop->_base != NULL) && (iop->_flag & _IOMYBUF))
57 free((char *)iop->_base - PUSHBACK);
58 iop->_flag &= ~(_IOMYBUF | _IONBF | _IOLBF);
59 if (buf == NULL) {
60 iop->_flag |= _IONBF;
61 if (fno == 0 || fno == 1) {
62 /* use special buffer for std{in,out} */
63 buf = (fno == 0) ? _sibuf : _sobuf;
64 } else if (fno >= 2 && fno < _NFILE) {
65 buf = _smbuf[fno];
66 size = _SMBFSZ - PUSHBACK;
67 } else if ((buf = (Uchar *)malloc(_SMBFSZ *
68 sizeof (Uchar))) != NULL) {
69 iop->_flag |= _IOMYBUF;
70 size = _SMBFSZ - PUSHBACK;
71 }
72 } else { /* regular buffered I/O, standard buffer size */
73 if (fno != -1) {
74 /*
75 * isatty(3C) will set errno as a side-effect of
76 * returning 0. Hide this from callers so that they do
77 * not see errno changing for no apparent reason.
78 */
79 int err = errno;
80 if (isatty(fno) != 0)
81 iop->_flag |= _IOLBF;
82 errno = err;
83 }
84 }
85 if (buf == NULL) {
86 FUNLOCKFILE(lk);
87 return; /* malloc() failed */
88 }
89 temp = buf + PUSHBACK;
90 iop->_base = temp;
91 _setbufend(iop, temp + size);
92 iop->_ptr = temp;
93 iop->_cnt = 0;
94 FUNLOCKFILE(lk);
95 }
96