/*
    * Copyright (C) 2012, Google Inc.
    * and other copyright owners as documented in the project's IP log.
    *
    * This program and the accompanying materials are made available
    * under the terms of the Eclipse Distribution License v1.0 which
    * accompanies this distribution, is reproduced below, and is
    * available at http://www.eclipse.org/org/documents/edl-v10.php
    *
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or
   * without modification, are permitted provided that the following
   * conditions are met:
   *
   * - Redistributions of source code must retain the above copyright
   *   notice, this list of conditions and the following disclaimer.
   *
   * - Redistributions in binary form must reproduce the above
   *   copyright notice, this list of conditions and the following
   *   disclaimer in the documentation and/or other materials provided
   *   with the distribution.
   *
   * - Neither the name of the Eclipse Foundation, Inc. nor the
   *   names of its contributors may be used to endorse or promote
   *   products derived from this software without specific prior
   *   written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
   * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
   * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
   * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  package org.eclipse.jgit.internal.storage.file;
  
  import java.io.DataInput;
  import java.io.IOException;
  import java.io.InputStream;
  
  import org.eclipse.jgit.util.IO;
  import org.eclipse.jgit.util.NB;
  
  /**
   * An implementation of DataInput that only handles readInt() and readLong()
   * using the Git conversion utilities for network byte order handling. This is
   * needed to read {@link com.googlecode.javaewah.EWAHCompressedBitmap}s.
   */
  class SimpleDataInput implements DataInput {
  	private final InputStream fd;
  
  	private final byte[] buf = new byte[8];
  
  	SimpleDataInput(InputStream fd) {
  		this.fd = fd;
  	}
  
  	@Override
  	public int readInt() throws IOException {
  		readFully(buf, 0, 4);
  		return NB.decodeInt32(buf, 0);
  	}
  
  	@Override
  	public long readLong() throws IOException {
  		readFully(buf, 0, 8);
  		return NB.decodeInt64(buf, 0);
  	}
  
  	public long readUnsignedInt() throws IOException {
  		readFully(buf, 0, 4);
  		return NB.decodeUInt32(buf, 0);
  	}
  
  	@Override
  	public void readFully(byte[] b) throws IOException {
  		readFully(b, 0, b.length);
  	}
  
  	@Override
  	public void readFully(byte[] b, int off, int len) throws IOException {
  		IO.readFully(fd, b, off, len);
  	}
  
  	@Override
  	public int skipBytes(int n) throws IOException {
  		throw new UnsupportedOperationException();
  	}
  
  	@Override
 	public boolean readBoolean() throws IOException {
 		throw new UnsupportedOperationException();
 	}
 
 	@Override
 	public byte readByte() throws IOException {
 		throw new UnsupportedOperationException();
 	}
 
 	@Override
 	public int readUnsignedByte() throws IOException {
 		throw new UnsupportedOperationException();
 	}
 
 	@Override
 	public short readShort() throws IOException {
 		throw new UnsupportedOperationException();
 	}
 
 	@Override
 	public int readUnsignedShort() throws IOException {
 		throw new UnsupportedOperationException();
 	}
 
 	@Override
 	public char readChar() throws IOException {
 		throw new UnsupportedOperationException();
 	}
 
 	@Override
 	public float readFloat() throws IOException {
 		throw new UnsupportedOperationException();
 	}
 
 	@Override
 	public double readDouble() throws IOException {
 		throw new UnsupportedOperationException();
 	}
 
 	@Override
 	public String readLine() throws IOException {
 		throw new UnsupportedOperationException();
 	}
 
 	@Override
 	public String readUTF() throws IOException {
 		throw new UnsupportedOperationException();
 	}
 }