public void writeStream(DataInputStream input) throws IOException, NoSuchAlgorithmException {
try {
int bytesRead = 0;
int bytesToSkip = 0;
while (true) {
final int value = input.readUnsignedByte();
bytesRead++;
check.nextByte(value);
writeRaw(value);
final int weakChecksum = check.weakChecksum();
String strongChecksum = null;
if (bytesToSkip > 0) {
bytesToSkip--;
} else {
Map<String, Integer> weakMatches = inputBlocks.get(weakChecksum);
if (weakMatches != null) {
strongChecksum = check.strongChecksum();
Integer previousOffset = weakMatches.get(strongChecksum);
if (previousOffset != null) {
snipRawBuffer();
System.err.println(
"Using previously remembered : "
+ previousOffset
+ " : "
+ (bytesRead - BLOCK_SIZE));
writeBlock(previousOffset);
bytesToSkip = BLOCK_SIZE - 1;
}
}
}
if ((bytesRead % BLOCK_SIZE) == 0) {
Map<String, Integer> weakMatches = inputBlocks.get(weakChecksum);
if (weakMatches == null) {
weakMatches = new HashMap<String, Integer>();
inputBlocks.put(weakChecksum, weakMatches);
}
if (strongChecksum == null) {
strongChecksum = check.strongChecksum();
}
if (!weakMatches.containsKey(strongChecksum)) {
weakMatches.put(strongChecksum, bytesRead - BLOCK_SIZE);
System.err.println(
"Remembering : "
+ weakChecksum
+ " : "
+ strongChecksum
+ " : "
+ (bytesRead - BLOCK_SIZE));
}
}
}
} catch (EOFException e) {
flushRaw();
}
System.err.println("Original data: " + rawChunks);
System.err.println("Reused data: " + blockChunks);
}
public static FileDesc loadFile(Path root, Path file, int blocSize)
throws NoSuchAlgorithmException, FileNotFoundException, IOException {
MessageDigest md = MessageDigest.getInstance("SHA-512");
MessageDigest fileMd = MessageDigest.getInstance("SHA-512");
FileDesc desc = new FileDesc(file.toString(), null, null);
List<Bloc> list = new ArrayList<Bloc>();
try (FileInputStream fis = new FileInputStream(root.resolve(file).toString())) {
byte[] buf = new byte[blocSize];
byte[] h;
int s;
while ((s = fis.read(buf)) != -1) {
int c;
while (s < buf.length && (c = fis.read()) != -1) buf[s++] = (byte) c;
fileMd.update(buf, 0, s);
// padding
byte p = 0;
while (s < buf.length) buf[s++] = ++p;
h = md.digest(buf);
Bloc bloc = new Bloc(RollingChecksum.compute(buf), new Hash(h));
list.add(bloc);
}
h = fileMd.digest();
desc.fileHash = new Hash(h);
desc.blocs = list.toArray(new Bloc[0]);
}
return desc;
}
