Add algorithm but did not implement it

doc/protocol.md

@@ -57,7 +57,7 @@ Payload contains
 
 ```
 [64-127: OFFSET OF FILE CONTENT IN BYTES]
-[128-159: TOTAL FILESIZE]
+[128-191: TOTAL FILESIZE]
 [<FILENAME>\n]
 [FILE CONTENT]
 ```

src/protocolP2P/FileList.java

@@ -51,14 +51,14 @@ public class FileList extends Payload {
 	 * @return datagram with padding
 	 */
 	protected byte[] toDatagram() {
-		byte[] datagram; // java initialize all to zero
+		//TODO compute size
+		int size = ;
+		byte[] datagram = new byte[size]; // java initialize all to zero
 		// size is keep blank (ProtocolP2PDatagram will handle it)
 		// set request/response code
 		datagram[RequestResponseCode.RRCODE_POSITION] = requestResponseCode.codeValue;
 		// bits 16-31 are reserved for future use
-		//TODO size
-		int size = ;
 		datagram = setPayloadSize(size, datagram);
-		//TODO content
+		//TODO Write content
 	}
 }

src/protocolP2P/FilePart.java

@@ -13,8 +13,8 @@ import exception.InternalError;
 public class FilePart extends Payload {
 	private static final RequestResponseCode requestResponseCode = RequestResponseCode.LOAD_RESPONSE;
 	private String filename;
-	private int totalSize;
-	private int offset;
+	private long totalSize;
+	private long offset;
 	private byte[] partialContent;
 
 	/** Constructor (typically used by server) with informations about file part to send as parameters.
@@ -22,8 +22,15 @@ public class FilePart extends Payload {
 	 * @param totalSize	total size of the file to send
 	 * @param offset	where in the file begins the part we are sending
 	 * @param partialContent	content of the file we send
+	 * @throws	InternalError
 	 */
-	public FilePart(String filename, int totalSize, int offset, byte[] partialContent) {
+	public FilePart(String filename, long totalSize, long offset, byte[] partialContent) throws InternalError {
+		/* asserts to help debugging */
+		assert totalSize >= 0 : "totalSize cannot be negative";
+		assert offset >= 0 : "offset cannot be negative";
+		if (totalSize < 0 || offset < 0) {
+			throw new InternalError();
+		}
 		this.filename = filename;
 		this.totalSize = totalSize;
 		this.offset = offset;
@@ -36,14 +43,17 @@ public class FilePart extends Payload {
 	 * @throws	InternalError
 	 */
 	public FilePart(byte[] datagram) throws ProtocolError, InternalError {
-		//TODO
 		/* assert to help debugging */
 		assert RequestResponseCode.fromCode(datagram[RequestResponseCode.RRCODE_POSITION]) == RequestResponseCode.LOAD_RESPONSE : "FilePart subclass is incompatible with this datagram, request/response code must be checked before using this constructor";
 		/* InternalErrorException */
 		if (RequestResponseCode.fromCode(datagram[RequestResponseCode.RRCODE_POSITION]) != RequestResponseCode.LOAD_RESPONSE) {
 			throw new InternalError();
 		}
-		int size = getPayloadSize(datagram);
+		setOffset(datagram); // this can throw ProtocolError
+		setTotalFileSize(datagram); // this can throw ProtocolError
+		int size = getPayloadSize(datagram); // this can throw ProtocolError
+		int partialContentStart = setFilename(datagram, size) + 1; // this can throw ProtocolError
+		setPartialContent(datagram, partialContentStart, size);
 	}
 
 	/** Returns a byte[] containing datagram with padding.
@@ -52,15 +62,39 @@ public class FilePart extends Payload {
 	 * @return datagram with padding
 	 */
 	public byte[] toDatagram() {
-		byte[] datagram; // java initialize all to zero
+		//TODO : calculate payload size
+		int size = ;
+		byte[] datagram = new byte[size]; // java initialize all to zero
 		// size is keep blank (ProtocolP2PDatagram will handle it)
 		// set request/response code
 		datagram[RequestResponseCode.RRCODE_POSITION] = requestResponseCode.codeValue;
 		// bits 16-31 are reserved for future use
-		//TODO size
-		int size = ;
 		datagram = setPayloadSize(size, datagram);
-		//TODO content
+		//TODO : write offset to datagram
+		//TODO : write totalFileSize to datagram
+		//TODO : write filename\n to datagram
+		//TODO : write partialContent to datagram
+	}
+
+	private setOffset(byte[] datagram) throws ProtocolError {
+		//TODO: copy from 8 to 15 into long and write into offset.
+		// throw protocolerror if offset is < 0
+	}
+	private setTotalFileSize(byte[] datagram) throw ProtocolError {
+		// TODO: convert from byte 16 to 23 (included)
+		// into long and write into totalFileSize
+		// throw protocolerror if offset is < 0
+	}
+	private int setFilename(byte[] datagram, size) throws ProtocolError {
+		// TODO: copy datagram from byte 24 to the first \n (excluded)
+		// into filename unless we excess size
+		// (in this case the wrong size has been
+		// set by the emitter, it is a protocolerror)
+		// return position of the \n
+		
+	}
+	private setPartialContent(byte[] datagram, int start, size) {
+		// TODO: copy datagram from start to size into partialContent
 	}
 
 }

src/protocolP2P/Payload.java

@@ -69,10 +69,16 @@ public class Payload {
 	 * @param size	integer representing payload size
 	 * @param datagram	datagram to be completed
 	 * @return	datagram with payload’s size set
+	 * @throws	InternalError
 	 */ 
-	protected static byte[] setPayloadSize(int size, byte[] datagram) { 
+	protected static byte[] setPayloadSize(int size, byte[] datagram) throws InternalError {
+		/* assert to help debugging */
+		assert size >= 0: "Payload size cannont be negative";
+		if (size < 0) {
+			throw new InternalError();
+		}
 		for(int i=0;i<4;i++) {
-				datagram[Payload.PAYLOAD_SIZE_POSITON + i] = (byte) (size >> (8 * (3 - i)) & 0xFF);
+				datagram[Payload.PAYLOAD_SIZE_POSITON + i] = (byte) ((size >> (8 * (3 - i))) & 0xFF);
 			}
 		}
 		return datagram;
@@ -81,12 +87,16 @@ public class Payload {
 	/** Get payload’s size from a datagram.
 	 * @param datagram	the full datagram received
 	 * @return	integer representing payload size
+	 * @throws	ProtocolError
 	 */
-	protected static int getPayloadSize(byte[] datagram) {
+	protected static int getPayloadSize(byte[] datagram) throws ProtocolError {
 		int size = 0;
 		for(int i=0;i<4;i++) {
 			size |= ((int)datagram[PAYLOAD_SIZE_POSITON + i]) << (8* i);
 		}
+		if (size < 0) {
+			throw new ProtocolError();
+		}
 		return size;
 	}
 }