/*
* Copyright (c) 2007, 2011, 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.
*
* 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.
*/
/**
* Copyright (c) 2005, Regents of the University of California 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 University of California, Los Angeles 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.
*
* Created Sep 5, 2005
*/
package com.oracle.max.elf;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.ByteBuffer;
/**
* Supports reading of ELF values from an ELF file or a {@link ByteBuffer} (presumably read from an ELF file).
*/
public class ELFDataInputStream {
private boolean bigEndian;
private RandomAccessFile file;
private ByteBuffer buffer;
/**
* Setup to read from an ELF file, that is assumed to be positioned at the point reading should start.
* @param elfHeader
* @param f
*/
public ELFDataInputStream(ELFHeader elfHeader, RandomAccessFile f) {
bigEndian = elfHeader.isBigEndian();
file = f;
}
/**
* Setup to read from (and ELF file in) a {@link ByteBuffer}, positioned so that {@link ByteBuffer#get} gets the first byte to be accessed.
* @param elfHeader
* @param buffer
*/
public ELFDataInputStream(ELFHeader elfHeader, ByteBuffer buffer) {
bigEndian = elfHeader.isBigEndian();
this.buffer = buffer;
}
public byte read_Elf32_byte() throws IOException {
return (byte) read_1();
}
public int read_Elf32_uchar() throws IOException {
return read_1();
}
public int read_Elf32_Addr() throws IOException {
return read_4();
}
public short read_Elf32_Half() throws IOException {
return (short) read_2();
}
public int read_Elf32_Off() throws IOException {
return read_4();
}
public int read_Elf32_SWord() throws IOException {
return read_4();
}
public int read_Elf32_Word() throws IOException {
return read_4();
}
public byte read_Elf64_byte() throws IOException {
return (byte) read_1();
}
public int read_Elf64_uchar() throws IOException {
return read_1();
}
public long read_Elf64_Addr() throws IOException {
return read_8();
}
public short read_Elf64_Half() throws IOException {
return (short) read_2();
}
public long read_Elf64_Off() throws IOException {
return read_8();
}
public int read_Elf64_SWord() throws IOException {
return read_4();
}
public int read_Elf64_Word() throws IOException {
return read_4();
}
public long read_Elf64_XWord() throws IOException {
return read_8();
}
private int read_1() throws IOException {
if (file == null) {
return buffer.get() & 0xff;
} else {
return file.read() & 0xff;
}
}
private int read_2() throws IOException {
final int b1 = read_1();
final int b2 = read_1();
if (bigEndian) {
return asShort(b2, b1);
}
return asShort(b1, b2);
}
private int read_4() throws IOException {
final int b1 = read_1();
final int b2 = read_1();
final int b3 = read_1();
final int b4 = read_1();
if (bigEndian) {
return asInt(b4, b3, b2, b1);
}
return asInt(b1, b2, b3, b4);
}
private long read_8() throws IOException {
final int b1 = read_1();
final int b2 = read_1();
final int b3 = read_1();
final int b4 = read_1();
final int b5 = read_1();
final int b6 = read_1();
final int b7 = read_1();
final int b8 = read_1();
if (bigEndian) {
return asLong(b8, b7, b6, b5, b4, b3, b2, b1);
}
return asLong(b1, b2, b3, b4, b5, b6, b7, b8);
}
private short asShort(int bl, int bh) {
return (short) ((bh << 8) | bl);
}
private int asInt(int b1, int b2, int b3, int b4) {
return (b4 << 24) | (b3 << 16) | (b2 << 8) | b1;
}
private long asLong(int b1, int b2, int b3, int b4, int b5, int b6, int b7, int b8) {
final long lw = (b4 << 24) | (b3 << 16) | (b2 << 8) | b1;
final long hw = (b8 << 24) | (b7 << 16) | (b6 << 8) | b5;
return hw << 32 | (lw & 0xffffffffL);
}
}