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/*-
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 * Copyright (c) 1990, 1993
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 *        The Regents of the University of California.  All rights reserved.
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 *
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 * This code is derived from software contributed to Berkeley by
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 * Chris Torek.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 * 3. Neither the name of the University nor the names of its contributors
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 *    may be used to endorse or promote products derived from this software
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 *    without specific prior written permission.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 */
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#include <stdio.h>
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#include <string.h>
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#include "local.h"
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size_t
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fread(buf, size, count, fp)
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        void *buf;
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        size_t size, count;
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        FILE *fp;
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{
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        size_t resid;
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        char *p;
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        int r;
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        size_t total;
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        /*
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         * The ANSI standard requires a return value of 0 for a count
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         * or a size of 0.  Peculiarily, it imposes no such requirements
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         * on fwrite; it only requires fread to be broken.
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         */
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        if ((resid = count * size) == 0)
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                return (0);
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        if (fp->_r < 0)
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                fp->_r = 0;
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        total = resid;
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        p = buf;
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        while (resid > (size_t)(r = fp->_r)) {
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                (void)memcpy((void *)p, (void *)fp->_p, (size_t)r);
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                fp->_p += r;
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                /* fp->_r = 0 ... done in __srefill */
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                p += r;
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                resid -= r;
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                if (__srefill(fp)) {
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                        /* no more input: return partial result */
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                        return ((total - resid) / size);
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                }
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        }
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        (void)memcpy((void *)p, (void *)fp->_p, resid);
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        fp->_r -= resid;
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        fp->_p += resid;
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        return (count);
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}