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/* |
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* $Id$ |
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* |
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* Copyright (C) 2003-2009 JNode.org |
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* |
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* This library is free software; you can redistribute it and/or modify it |
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* under the terms of the GNU Lesser General Public License as published |
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* by the Free Software Foundation; either version 2.1 of the License, or |
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* (at your option) any later version. |
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* |
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* This library is distributed in the hope that it will be useful, but |
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* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
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* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public |
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* License for more details. |
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* |
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* You should have received a copy of the GNU Lesser General Public License |
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* along with this library; If not, write to the Free Software Foundation, Inc., |
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
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*/ |
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|
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package org.jnode.vm; |
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|
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import org.jnode.system.MemoryScanner; |
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import org.jnode.annotation.MagicPermission; |
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import org.vmmagic.unboxed.Address; |
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import org.vmmagic.unboxed.Offset; |
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|
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|
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/** |
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* @author Ewout Prangsma (epr@users.sourceforge.net) |
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*/ |
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@MagicPermission |
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final class MemoryScannerImpl implements MemoryScanner { |
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|
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/** |
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* @see org.jnode.system.MemoryScanner#findInt16(org.jnode.vm.Address, int, int, int) |
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*/ |
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public Address findInt16(Address start, int size, int match, int stepSize) { |
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int offset = 0; |
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match &= 0xFFFF; |
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size -= 1; |
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while (offset < size) { |
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if ((start.loadShort(Offset.fromIntSignExtend(offset)) & 0xFFFF) == match) { |
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return start.add(offset); |
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} else { |
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offset += stepSize; |
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} |
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} |
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return null; |
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} |
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|
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/** |
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* @see org.jnode.system.MemoryScanner#findInt32(org.jnode.vm.Address, int, int, int) |
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*/ |
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public Address findInt32(Address start, int size, int match, int stepSize) { |
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int offset = 0; |
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size -= 3; |
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while (offset < size) { |
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if (start.loadInt(Offset.fromIntSignExtend(offset)) == match) { |
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return start.add(offset); |
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} else { |
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offset += stepSize; |
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} |
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} |
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return null; |
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} |
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|
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/** |
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* @see org.jnode.system.MemoryScanner#findInt64(org.jnode.vm.Address, int, long, int) |
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*/ |
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public Address findInt64(Address start, int size, long match, int stepSize) { |
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int offset = 0; |
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size -= 7; |
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while (offset < size) { |
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if (start.loadLong(Offset.fromIntSignExtend(offset)) == match) { |
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return start.add(offset); |
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} else { |
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offset += stepSize; |
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} |
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} |
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return null; |
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} |
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|
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/** |
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* @see org.jnode.system.MemoryScanner#findInt8(org.jnode.vm.Address, int, int, int) |
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*/ |
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public Address findInt8(Address start, int size, int match, int stepSize) { |
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int offset = 0; |
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match &= 0xFF; |
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while (offset < size) { |
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if ((start.loadByte(Offset.fromIntSignExtend(offset)) & 0xFF) == match) { |
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return start.add(offset); |
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} else { |
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offset += stepSize; |
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} |
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} |
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return null; |
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} |
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|
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/** |
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* @see org.jnode.system.MemoryScanner#findInt8Array(org.jnode.vm.Address, int, byte[], int, int, int) |
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*/ |
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public Address findInt8Array(Address start, int size, byte[] match, |
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int matchOffset, int matchLength, int stepSize) { |
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int offset = 0; |
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size -= (matchLength - 1); |
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final int match0 = match[matchOffset] & 0xFF; |
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while (offset < size) { |
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if ((start.loadByte(Offset.fromIntSignExtend(offset)) & 0xFF) == match0) { |
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if (isMatch(start, offset, match, matchOffset, matchLength)) { |
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return start.add(offset); |
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} |
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} |
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offset += stepSize; |
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} |
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return null; |
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} |
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|
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/** |
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* @see org.jnode.system.MemoryScanner#findInt16Array(org.jnode.vm.Address, int, char[], int, int, int) |
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*/ |
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public Address findInt16Array(Address start, int size, char[] match, |
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int matchOffset, int matchLength, int stepSize) { |
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int offset = 0; |
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size -= ((matchLength * 2) - 1); |
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final int match0 = match[matchOffset] & 0xFFFF; |
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while (offset < size) { |
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if ((start.loadChar(Offset.fromIntSignExtend(offset)) & 0xFFFF) == match0) { |
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if (isMatch(start, offset, match, matchOffset, matchLength)) { |
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return start.add(offset); |
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} |
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} |
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offset += stepSize; |
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} |
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return null; |
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} |
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|
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/** |
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* @see org.jnode.system.MemoryScanner#findInt16Array(org.jnode.vm.Address, int, short[], int, int, int) |
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*/ |
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public Address findInt16Array(Address start, int size, short[] match, |
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int matchOffset, int matchLength, int stepSize) { |
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int offset = 0; |
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size -= ((matchLength * 2) - 1); |
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final int match0 = match[matchOffset] & 0xFFFF; |
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while (offset < size) { |
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if ((start.loadShort(Offset.fromIntSignExtend(offset)) & 0xFFFF) == match0) { |
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if (isMatch(start, offset, match, matchOffset, matchLength)) { |
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return start.add(offset); |
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} |
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} |
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offset += stepSize; |
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} |
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return null; |
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} |
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|
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/** |
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* @see org.jnode.system.MemoryScanner#findInt32Array(org.jnode.vm.Address, int, int[], int, int, int) |
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*/ |
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public Address findInt32Array(Address start, int size, int[] match, |
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int matchOffset, int matchLength, int stepSize) { |
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int offset = 0; |
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size -= ((matchLength * 4) - 1); |
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final int match0 = match[matchOffset]; |
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while (offset < size) { |
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if (start.loadInt(Offset.fromIntSignExtend(offset)) == match0) { |
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if (isMatch(start, offset, match, matchOffset, matchLength)) { |
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return start.add(offset); |
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} |
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} |
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offset += stepSize; |
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} |
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return null; |
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} |
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|
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/** |
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* @see org.jnode.system.MemoryScanner#findInt64Array(org.jnode.vm.Address, int, long[], int, int, int) |
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*/ |
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public Address findInt64Array(Address start, int size, long[] match, |
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int matchOffset, int matchLength, int stepSize) { |
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int offset = 0; |
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size -= ((matchLength * 8) - 1); |
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final long match0 = match[matchOffset]; |
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while (offset < size) { |
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if (start.loadLong(Offset.fromIntSignExtend(offset)) == match0) { |
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if (isMatch(start, offset, match, matchOffset, matchLength)) { |
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return start.add(offset); |
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} |
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} |
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offset += stepSize; |
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} |
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return null; |
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} |
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|
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private final boolean isMatch(Address start, int offset, byte[] match, |
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int matchOffset, int matchLength) { |
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for (int i = 0; i < matchLength; i++) { |
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if ((start.loadByte(Offset.fromIntSignExtend(offset + i)) & 0xFF) != (match[matchOffset + i] & 0xFF)) { |
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return false; |
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} |
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} |
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return true; |
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} |
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|
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private final boolean isMatch(Address start, int offset, char[] match, |
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int matchOffset, int matchLength) { |
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for (int i = 0; i < matchLength; i++) { |
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if ((start.loadChar(Offset.fromIntSignExtend(offset + (i * 2))) & 0xFFFF) != |
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(match[matchOffset + i] & 0xFFFF)) { |
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return false; |
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} |
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} |
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return true; |
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} |
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|
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private final boolean isMatch(Address start, int offset, short[] match, |
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int matchOffset, int matchLength) { |
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for (int i = 0; i < matchLength; i++) { |
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if ((start.loadShort(Offset.fromIntSignExtend(offset + (i * 2))) & 0xFFFF) != |
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(match[matchOffset + i] & 0xFFFF)) { |
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return false; |
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} |
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} |
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return true; |
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} |
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|
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private final boolean isMatch(Address start, int offset, int[] match, |
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int matchOffset, int matchLength) { |
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for (int i = 0; i < matchLength; i++) { |
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if (start.loadInt(Offset.fromIntSignExtend(offset + (i * 4))) != match[matchOffset + i]) { |
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return false; |
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} |
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} |
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return true; |
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} |
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|
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private final boolean isMatch(Address start, int offset, long[] match, |
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int matchOffset, int matchLength) { |
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for (int i = 0; i < matchLength; i++) { |
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if (start.loadLong(Offset.fromIntSignExtend(offset + (i * 8))) != match[matchOffset + i]) { |
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return false; |
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} |
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} |
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return true; |
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} |
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} |
