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The file system driver family for ZIP and related archive file types. Add the JAR artifact of this module to the run time class path to make its file system drivers available for service location in the client API modules.

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/*
 * Copyright (C) 2005-2013 Schlichtherle IT Services.
 * All rights reserved. Use is subject to license terms.
 */
package de.schlichtherle.truezip.zip;

import de.schlichtherle.truezip.rof.ReadOnlyFile;
import de.schlichtherle.truezip.rof.ReadOnlyFileInputStream;
import edu.umd.cs.findbugs.annotations.CreatesObligation;
import java.io.IOException;
import javax.annotation.WillCloseWhenClosed;

/**
 * A read only file input stream which adds a dummy zero byte to the end of
 * the input in order to support {@link ZipInflaterInputStream}.
 *
 * @author  Christian Schlichtherle
 */
final class DummyByteInputStream extends ReadOnlyFileInputStream {
    private boolean added;

    @CreatesObligation
    @edu.umd.cs.findbugs.annotations.SuppressWarnings("OBL_UNSATISFIED_OBLIGATION")
    DummyByteInputStream(@WillCloseWhenClosed ReadOnlyFile rof) {
        super(rof);
    }

    @Override
    public int read() throws IOException {
        final int read = rof.read();
        if (read < 0 && !added) {
            added = true;
            return 0;
        }
        return read;
    }

    @Override
    public int read(final byte[] buf, final int off, int len) throws IOException {
        if (0 == len)
            return 0;
        final int read = rof.read(buf, off, len);
        if (read < len && !added) {
            added = true;
            if (read < 0) {
                buf[0] = 0;
                return 1;
            } else {
                buf[read] = 0;
                return read + 1;
            }
        }
        return read;
    }

    @Override
    public int available() throws IOException {
        int available = super.available();
        return added || available >= Integer.MAX_VALUE ? available : available + 1;
    }
}