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      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 #pragma ident	"%Z%%M%	%I%	%E% SMI"
     31 
     32 #include "lint.h"
     33 #include "file64.h"
     34 #include "mtlib.h"
     35 #include <sys/types.h>
     36 #include <stdio.h>
     37 #include <stdlib.h>
     38 #include <thread.h>
     39 #include <synch.h>
     40 #include "stdiom.h"
     41 
     42 int
     43 setvbuf(FILE *iop, char *abuf, int type, size_t size)
     44 {
     45 
     46 	Uchar	*buf = (Uchar *)abuf;
     47 	Uchar *temp;
     48 	int	sflag = iop->_flag & _IOMYBUF;
     49 	rmutex_t *lk;
     50 	int fd = GET_FD(iop);
     51 
     52 	FLOCKFILE(lk, iop);
     53 	iop->_flag &= ~(_IOMYBUF | _IONBF | _IOLBF);
     54 	switch (type) {
     55 	/* note that the flags are the same as the possible values for type */
     56 	case _IONBF:
     57 		iop->_flag |= _IONBF;	 /* file is unbuffered */
     58 #ifndef _STDIO_ALLOCATE
     59 		if (fd < 2) {
     60 			/* use special buffer for std{in,out} */
     61 			buf = (fd == 0) ? _sibuf : _sobuf;
     62 			size = BUFSIZ;
     63 		} else /* needed for ifdef */
     64 #endif
     65 		if (fd < _NFILE) {
     66 			buf = _smbuf[fd];
     67 			size = _SMBFSZ - PUSHBACK;
     68 		} else
     69 			if ((buf = malloc(_SMBFSZ * sizeof (Uchar))) != NULL) {
     70 				iop->_flag |= _IOMYBUF;
     71 				size = _SMBFSZ - PUSHBACK;
     72 			} else {
     73 				FUNLOCKFILE(lk);
     74 				return (EOF);
     75 			}
     76 		break;
     77 	case _IOLBF:
     78 	case _IOFBF:
     79 		iop->_flag |= type;	/* buffer file */
     80 		/*
     81 		 * need at least an 8 character buffer for
     82 		 * out_of_sync concerns.
     83 		 */
     84 		if (size <= _SMBFSZ) {
     85 			size = BUFSIZ;
     86 			buf = NULL;
     87 		}
     88 		if (buf == NULL) {
     89 			if ((buf = malloc(sizeof (Uchar) *
     90 			    (size + _SMBFSZ))) != NULL)
     91 				iop->_flag |= _IOMYBUF;
     92 			else {
     93 				FUNLOCKFILE(lk);
     94 				return (EOF);
     95 			}
     96 		}
     97 		else
     98 			size -= _SMBFSZ;
     99 		break;
    100 	default:
    101 		FUNLOCKFILE(lk);
    102 		return (EOF);
    103 	}
    104 	if (iop->_base != NULL && sflag)
    105 		free((char *)iop->_base - PUSHBACK);
    106 	temp = buf + PUSHBACK;
    107 	iop->_base = temp;
    108 	_setbufend(iop, temp + size);
    109 	iop->_ptr = temp;
    110 	iop->_cnt = 0;
    111 	FUNLOCKFILE(lk);
    112 	return (0);
    113 }
    114