/*

 * Copyright (c) 2005, 2017, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package sun.net.httpserver;

import java.io.*;

import java.net.*;

import com.sun.net.httpserver.*;

import com.sun.net.httpserver.spi.*;

/**

 * a class which allows the caller to read up to a defined

 * number of bytes off an underlying stream

 * close() does not close the underlying stream

 */

class FixedLengthInputStream extends LeftOverInputStream {

    private long remaining;

    FixedLengthInputStream (ExchangeImpl t, InputStream src, long len) {

        super (t, src);

        this.remaining = len;

    }

    protected int readImpl (byte[]b, int off, int len) throws IOException {

        eof = (remaining == 0L);

        if (eof) {

            return -1;

        }

        if (len > remaining) {

            len = (int)remaining;

        }

        int n = in.read(b, off, len);

        if (n > -1) {

            remaining -= n;

            if (remaining == 0) {

                t.getServerImpl().requestCompleted (t.getConnection());

            }

        }

        if (n < 0 && !eof)

            throw new IOException("connection closed before all data received");

        return n;

    }

    public int available () throws IOException {

        if (eof) {

            return 0;

        }

        int n = in.available();

        return n < remaining? n: (int)remaining;

    }

    public boolean markSupported () {return false;}

    public void mark (int l) {

    }

    public void reset () throws IOException {

        throw new IOException ("mark/reset not supported");

    }

}