/*
 * 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 <values.h>
#include <memory.h>
#include <thread.h>
#include <synch.h>
#include <unistd.h>
#include "stdiom.h"
#include "mse.h"

size_t
_fwrite_unlocked(const void *ptr, size_t size, size_t count, FILE *iop);

size_t
fwrite(const void *ptr, size_t size, size_t count, FILE *iop)
{
        rmutex_t        *lk;
        size_t  retval;

        FLOCKFILE(lk, iop);

        _SET_ORIENTATION_BYTE(iop);

        retval = _fwrite_unlocked(ptr, size, count, iop);
        FUNLOCKFILE(lk);

        return (retval);
}

size_t
_fwrite_unlocked(const void *ptr, size_t size, size_t count, FILE *iop)
{
        ssize_t s, n;
        unsigned char *dptr = (unsigned char *)ptr;
        unsigned char *bufend;

        if (_WRTCHK(iop))
                return (0);

        /*
         * This test is here to avoid the expensive multiply
         */
        if (count == 1)
                s = size;
        else if (size == 1)
                s = count;
        else
                s = size * count;

        if (iop->_flag & _IOLBF) {
                bufend = _bufend(iop);
                iop->_cnt = iop->_base - iop->_ptr;
                while (s > 0) {
                        ssize_t buflen = bufend - iop->_base;
                        if (--iop->_cnt >= (-buflen) && *dptr != '\n')
                                *iop->_ptr++ = *dptr++;
                        else if (__flsbuf(*dptr++, iop) == EOF)
                                break;
                        s--;
                }
        } else if (iop->_flag & _IONBF) {
                ssize_t bytes;
                ssize_t written = 0;
                char *data;

                if (size < 1 || count < 1)
                        return (0);

                if (iop->_base != iop->_ptr) {
                /*
                 * Flush any existing data. Doesn't count towards return
                 * value.
                 */
                        bytes = iop->_ptr - iop->_base;
                        data = (char *)iop->_base;

                        while ((n = _xwrite(iop, data, (size_t)bytes)) !=
                            bytes) {
                                if (n <= 0) {
                                        if (!cancel_active())
                                                iop->_flag |= _IOERR;
                                        return (0);
                                } else {
                                        data += n;
                                        bytes -= n;
                                }
                        }
                        iop->_cnt = 0;
                        iop->_ptr = iop->_base;
                }
                /*
                 * written is in bytes until the return.
                 * Then it is divided by size to produce items.
                 */
                while ((n = _xwrite(iop, dptr, s)) != s) {
                        if (n <= 0) {
                                if (!cancel_active())
                                        iop->_flag |= _IOERR;
                                return (written / size);
                        } else {
                                dptr += n;
                                s -= n;
                                written += n;
                        }
                }
                written += n;
                return (written / size);
        } else while (s > 0) {
                if (iop->_cnt < s) {
                        if (iop->_cnt > 0) {
                                (void) memcpy(iop->_ptr, (void *)dptr,
                                    iop->_cnt);
                                dptr += iop->_cnt;
                                iop->_ptr += iop->_cnt;
                                s -= iop->_cnt;
                        }
                        if (_xflsbuf(iop) == EOF)
                                break;
                }
                if (iop->_cnt >= s) {
                        char *tmp = (char *)iop->_ptr;

                        switch (s) {
                        case 8:
                                *tmp++ = *dptr++;
                                /*FALLTHRU*/
                        case 7:
                                *tmp++ = *dptr++;
                                /*FALLTHRU*/
                        case 6:
                                *tmp++ = *dptr++;
                                /*FALLTHRU*/
                        case 5:
                                *tmp++ = *dptr++;
                                /*FALLTHRU*/
                        case 4:
                                *tmp++ = *dptr++;
                                /*FALLTHRU*/
                        case 3:
                                *tmp++ = *dptr++;
                                /*FALLTHRU*/
                        case 2:
                                *tmp++ = *dptr++;
                                /*FALLTHRU*/
                        case 1:
                                *tmp++ = *dptr++;
                                break;
                        case 0:
                                return (count);
                        default:
                                (void) memcpy(iop->_ptr, (void *)dptr, s);
                        }
                        iop->_ptr += s;
                        iop->_cnt -= s;

                        return (count);
                }
        }

        return (size != 0 ? count - ((s + size - 1) / size) : 0);
}