/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*      Copyright (c) 1988 AT&T */
/*        All Rights Reserved   */

#include "lint.h"
#include "file64.h"
#include "mtlib.h"
#include <sys/types.h>
#include <stdio.h>
#include <stdlib.h>
#include <thread.h>
#include <synch.h>
#include "stdiom.h"

int
setvbuf(FILE *iop, char *abuf, int type, size_t size)
{

        Uchar   *buf = (Uchar *)abuf;
        Uchar *temp;
        int     sflag = iop->_flag & _IOMYBUF;
        rmutex_t *lk;
        int fd = _get_fd(iop);

        FLOCKFILE(lk, iop);
        iop->_flag &= ~(_IOMYBUF | _IONBF | _IOLBF);
        switch (type) {
        /* note that the flags are the same as the possible values for type */
        case _IONBF:
                iop->_flag |= _IONBF;    /* file is unbuffered */
                if (fd == 0 || fd == 1) {
                        /* use special buffer for std{in,out} */
                        buf = (fd == 0) ? _sibuf : _sobuf;
                        size = BUFSIZ;
                } else if (fd >= 2 && fd < _NFILE) {
                        buf = _smbuf[fd];
                        size = _SMBFSZ - PUSHBACK;
                } else {
                        if ((buf = malloc(_SMBFSZ * sizeof (Uchar))) != NULL) {
                                iop->_flag |= _IOMYBUF;
                                size = _SMBFSZ - PUSHBACK;
                        } else {
                                FUNLOCKFILE(lk);
                                return (EOF);
                        }
                }
                break;
        case _IOLBF:
        case _IOFBF:
                iop->_flag |= type;     /* buffer file */
                /*
                 * need at least an 8 character buffer for
                 * out_of_sync concerns.
                 */
                if (size <= _SMBFSZ) {
                        size = BUFSIZ;
                        buf = NULL;
                }
                if (buf == NULL) {
                        if ((buf = malloc(sizeof (Uchar) *
                            (size + _SMBFSZ))) != NULL)
                                iop->_flag |= _IOMYBUF;
                        else {
                                FUNLOCKFILE(lk);
                                return (EOF);
                        }
                }
                else
                        size -= _SMBFSZ;
                break;
        default:
                FUNLOCKFILE(lk);
                return (EOF);
        }
        if (iop->_base != NULL && sflag)
                free((char *)iop->_base - PUSHBACK);
        temp = buf + PUSHBACK;
        iop->_base = temp;
        _setbufend(iop, temp + size);
        iop->_ptr = temp;
        iop->_cnt = 0;
        FUNLOCKFILE(lk);
        return (0);
}