Code:
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
/**
* Manages the reading and writing for a particular file store in the cache.
*/
public class FileStore {
private static final int IDX_BLOCK_LEN = 6;
private static final int HEADER_LEN = 8;
private static final int EXPANDED_HEADER_LEN = 10;
private static final int BLOCK_LEN = 512;
private static final int EXPANDED_BLOCK_LEN = 510;
private static final int TOTAL_BLOCK_LEN = HEADER_LEN + BLOCK_LEN;
private static ByteBuffer tempBuffer = ByteBuffer.allocateDirect(TOTAL_BLOCK_LEN);
private int index;
private FileChannel indexChannel;
private FileChannel dataChannel;
private int maxSize;
/**
* Creates a new FileStore object.
* @param index The index of this file store.
* @param dataChannel The channel of the data file for this file store.
* @param indexChannel The channel of the index file for this file store.
* @param maxSize The maximum size of a file in this file store.
*/
public FileStore(int index, FileChannel dataChannel,
FileChannel indexChannel, int maxSize) {
this.index = index;
this.dataChannel = dataChannel;
this.indexChannel = indexChannel;
this.maxSize = maxSize;
}
/**
* Gets the number of files stored in this file store.
* @return This file store's file count.
*/
public int getFileCount() {
try {
return (int) (indexChannel.size() / IDX_BLOCK_LEN);
} catch (IOException ex) {
return 0;
}
}
/**
* Reads a file from the file store.
* @param file The file to read.
* @return The file's data, or null if the file was invalid.
*/
public mgi.tools.rseditor.core.utilities.ByteBuffer get(int file) {
try {
if (file * IDX_BLOCK_LEN + IDX_BLOCK_LEN > indexChannel.size()) {
return null;
}
tempBuffer.position(0).limit(IDX_BLOCK_LEN);
indexChannel.read(tempBuffer, file * IDX_BLOCK_LEN);
tempBuffer.flip();
int size = getMediumInt(tempBuffer);
int block = getMediumInt(tempBuffer);
if (size < 0 || size > maxSize) {
return null;
}
if (block <= 0 || block > dataChannel.size() / TOTAL_BLOCK_LEN) {
return null;
}
mgi.tools.rseditor.core.utilities.ByteBuffer fileBuffer = new mgi.tools.rseditor.core.utilities.ByteBuffer(size);
int remaining = size;
int chunk = 0;
int blockLen = file <= 0xffff ? BLOCK_LEN : EXPANDED_BLOCK_LEN;
int headerLen = file <= 0xffff ? HEADER_LEN : EXPANDED_HEADER_LEN;
while (remaining > 0) {
if (block == 0) {
return null;
}
int blockSize = remaining > blockLen ? blockLen : remaining;
tempBuffer.position(0).limit(blockSize + headerLen);
dataChannel.read(tempBuffer, block * TOTAL_BLOCK_LEN);
tempBuffer.flip();
int currentFile, currentChunk, nextBlock, currentIndex;
if (file <= 65535) {
currentFile = tempBuffer.getShort() & 0xffff;
currentChunk = tempBuffer.getShort() & 0xffff;
nextBlock = getMediumInt(tempBuffer);
currentIndex = tempBuffer.get() & 0xff;
} else {
currentFile = tempBuffer.getInt();
currentChunk = tempBuffer.getShort() & 0xffff;
nextBlock = getMediumInt(tempBuffer);
currentIndex = tempBuffer.get() & 0xff;
}
if (file != currentFile || chunk != currentChunk || index != currentIndex) {
return null;
}
if (nextBlock < 0 || nextBlock > dataChannel.size() / TOTAL_BLOCK_LEN) {
return null;
}
int rem = tempBuffer.remaining();
for (int i = 0; i < rem; i++)
fileBuffer.writeByte(tempBuffer.get());
remaining -= blockSize;
block = nextBlock;
chunk++;
}
fileBuffer.setPosition(0);
return fileBuffer;
} catch (IOException ex) {
return null;
}
}
/**
* Writes an item to the file store.
* @param file The file to write.
* @param data The file's data.
* @param size The size of the file.
* @return true if the file was written, false otherwise.
*/
public boolean put(int file, mgi.tools.rseditor.core.utilities.ByteBuffer data, int size) {
if (size < 0 || size > maxSize) {
throw new IllegalArgumentException("File too big: " + file + " size: " + size);
}
boolean success = put(file, ByteBuffer.wrap(data.getBuffer()), size, true);
if (!success) {
success = put(file, ByteBuffer.wrap(data.getBuffer()), size, false);
}
return success;
}
private boolean put(int file, ByteBuffer data, int size, boolean exists) {
try {
int block;
if (exists) {
if (file * IDX_BLOCK_LEN + IDX_BLOCK_LEN > indexChannel.size()) {
return false;
}
tempBuffer.position(0).limit(IDX_BLOCK_LEN);
indexChannel.read(tempBuffer, file * IDX_BLOCK_LEN);
tempBuffer.flip().position(3);
block = getMediumInt(tempBuffer);
if (block <= 0 || block > dataChannel.size() / TOTAL_BLOCK_LEN) {
return false;
}
} else {
block = (int) (dataChannel.size() + TOTAL_BLOCK_LEN - 1) / TOTAL_BLOCK_LEN;
if (block == 0) {
block = 1;
}
}
tempBuffer.position(0);
putMediumInt(tempBuffer, size);
putMediumInt(tempBuffer, block);
tempBuffer.flip();
indexChannel.write(tempBuffer, file * IDX_BLOCK_LEN);
int remaining = size;
int chunk = 0;
int blockLen = file <= 0xffff ? BLOCK_LEN : EXPANDED_BLOCK_LEN;
int headerLen = file <= 0xffff ? HEADER_LEN : EXPANDED_HEADER_LEN;
while (remaining > 0) {
int nextBlock = 0;
if (exists) {
tempBuffer.position(0).limit(headerLen);
dataChannel.read(tempBuffer, block * TOTAL_BLOCK_LEN);
tempBuffer.flip();
int currentFile, currentChunk, currentIndex;
if (file <= 0xffff) {
currentFile = tempBuffer.getShort() & 0xffff;
currentChunk = tempBuffer.getShort() & 0xffff;
nextBlock = getMediumInt(tempBuffer);
currentIndex = tempBuffer.get() & 0xff;
} else {
currentFile = tempBuffer.getInt();
currentChunk = tempBuffer.getShort() & 0xffff;
nextBlock = getMediumInt(tempBuffer);
currentIndex = tempBuffer.get() & 0xff;
}
if (file != currentFile || chunk != currentChunk || index != currentIndex) {
return false;
}
if (nextBlock < 0 || nextBlock > dataChannel.size() / TOTAL_BLOCK_LEN) {
return false;
}
}
if (nextBlock == 0) {
exists = false;
nextBlock = (int) ((dataChannel.size() + TOTAL_BLOCK_LEN - 1) / TOTAL_BLOCK_LEN);
if (nextBlock == 0) {
nextBlock = 1;
}
if (nextBlock == block) {
nextBlock++;
}
}
if (remaining <= blockLen) {
nextBlock = 0;
}
tempBuffer.position(0).limit(TOTAL_BLOCK_LEN);
if (file <= 0xffff) {
tempBuffer.putShort((short) file);
tempBuffer.putShort((short) chunk);
putMediumInt(tempBuffer, nextBlock);
tempBuffer.put((byte) index);
} else {
tempBuffer.putInt(file);
tempBuffer.putShort((short) chunk);
putMediumInt(tempBuffer, nextBlock);
tempBuffer.put((byte) index);
}
int blockSize = remaining > blockLen ? blockLen : remaining;
data.limit(data.position() + blockSize);
tempBuffer.put(data);
tempBuffer.flip();
dataChannel.write(tempBuffer, block * TOTAL_BLOCK_LEN);
remaining -= blockSize;
block = nextBlock;
chunk++;
}
return true;
} catch (IOException ex) {
return false;
}
}
private static int getMediumInt(ByteBuffer buffer) {
return ((buffer.get() & 0xff) << 16) | ((buffer.get() & 0xff) << 8) |
(buffer.get() & 0xff);
}
private static void putMediumInt(ByteBuffer buffer, int val) {
buffer.put((byte) (val >> 16));
buffer.put((byte) (val >> 8));
buffer.put((byte) val);
}
public void setMaxSize(int size) {
this.maxSize = size;
}
/**
* Close's this store.
*/
public void close() {
try { this.dataChannel.close(); } catch (IOException e) {}
try { this.indexChannel.close(); } catch (IOException e) {}
}
}
Originally Posted by anon strike
Is this Volantis' Decompressor class? lol
