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 */
33
34#include "lint.h"
35#include "file64.h"
36#include "mtlib.h"
37#include <sys/types.h>
38#include <stdio.h>
39#include <stdlib.h>
40#include <thread.h>
41#include <synch.h>
42#include "stdiom.h"
43
44void
45setbuf(FILE *iop, char *abuf)
46{
47	Uchar *buf = (Uchar *)abuf;
48	int fno = _get_fd(iop);  /* file number */
49	int size = BUFSIZ - _SMBFSZ;
50	Uchar *temp;
51	rmutex_t *lk;
52
53	FLOCKFILE(lk, iop);
54	if ((iop->_base != NULL) && (iop->_flag & _IOMYBUF))
55		free((char *)iop->_base - PUSHBACK);
56	iop->_flag &= ~(_IOMYBUF | _IONBF | _IOLBF);
57	if (buf == NULL) {
58		iop->_flag |= _IONBF;
59		if (fno == 0 || fno == 1) {
60			/* use special buffer for std{in,out} */
61			buf = (fno == 0) ? _sibuf : _sobuf;
62		} else if (fno >= 2 && fno < _NFILE) {
63			buf = _smbuf[fno];
64			size = _SMBFSZ - PUSHBACK;
65		} else if ((buf = (Uchar *)malloc(_SMBFSZ *
66		    sizeof (Uchar))) != NULL) {
67			iop->_flag |= _IOMYBUF;
68			size = _SMBFSZ - PUSHBACK;
69		}
70	} else {	/* regular buffered I/O, standard buffer size */
71		if (fno != -1 && isatty(fno))
72			iop->_flag |= _IOLBF;
73	}
74	if (buf == NULL) {
75		FUNLOCKFILE(lk);
76		return;		/* malloc() failed */
77	}
78	temp = buf + PUSHBACK;
79	iop->_base = temp;
80	_setbufend(iop, temp + size);
81	iop->_ptr = temp;
82	iop->_cnt = 0;
83	FUNLOCKFILE(lk);
84}
85