diff --git a/briar-core/src/net/sf/briar/reliability/Ack.java b/briar-core/src/net/sf/briar/reliability/Ack.java
index a8c437bf94124beea0251308a1ac74e691223bdb..1d763528f2c7d99fff04634a107625fcfa5706c7 100644
--- a/briar-core/src/net/sf/briar/reliability/Ack.java
+++ b/briar-core/src/net/sf/briar/reliability/Ack.java
@@ -4,7 +4,7 @@ import net.sf.briar.util.ByteUtils;
class Ack extends Frame {
- static final int LENGTH = 12;
+ static final int LENGTH = 11;
Ack() {
super(new byte[LENGTH]);
@@ -18,10 +18,10 @@ class Ack extends Frame {
}
int getWindowSize() {
- return ByteUtils.readUint24(buf, 5);
+ return ByteUtils.readUint16(buf, 5);
}
void setWindowSize(int windowSize) {
- ByteUtils.writeUint24(windowSize, buf, 5);
+ ByteUtils.writeUint16(windowSize, buf, 5);
}
}
diff --git a/briar-core/src/net/sf/briar/reliability/Receiver.java b/briar-core/src/net/sf/briar/reliability/Receiver.java
index ddb3394aa67663a3d1123d4f0946151a171e4dfa..9072dbba312b20d62591cc147b44451b5e1eb08c 100644
--- a/briar-core/src/net/sf/briar/reliability/Receiver.java
+++ b/briar-core/src/net/sf/briar/reliability/Receiver.java
@@ -10,7 +10,8 @@ import net.sf.briar.api.reliability.ReadHandler;
class Receiver implements ReadHandler {
- static final int MAX_WINDOW_SIZE = 8 * Data.MAX_PAYLOAD_LENGTH;
+ private static final int READ_TIMEOUT = 5 * 60 * 1000; // Milliseconds
+ private static final int MAX_WINDOW_SIZE = 8 * Data.MAX_PAYLOAD_LENGTH;
private final Sender sender;
private final SortedSet<Data> dataFrames; // Locking: this
@@ -27,10 +28,11 @@ class Receiver implements ReadHandler {
}
synchronized Data read() throws IOException, InterruptedException {
- while(valid) {
+ long now = System.currentTimeMillis(), end = now + READ_TIMEOUT;
+ while(now < end && valid) {
if(dataFrames.isEmpty()) {
// Wait for a data frame
- wait();
+ wait(end - now);
} else {
Data d = dataFrames.first();
if(d.getSequenceNumber() == nextSequenceNumber) {
@@ -42,10 +44,12 @@ class Receiver implements ReadHandler {
return d;
} else {
// Wait for the next in-order data frame
- wait();
+ wait(end - now);
}
}
+ now = System.currentTimeMillis();
}
+ if(valid) throw new IOException("Read timed out");
throw new IOException("Connection closed");
}
diff --git a/briar-core/src/net/sf/briar/reliability/Sender.java b/briar-core/src/net/sf/briar/reliability/Sender.java
index 313c1cb71b4c859a0760869092a828d996189a2a..7ae6f69f85b10db71c3b1a6935ed054fea845c3b 100644
--- a/briar-core/src/net/sf/briar/reliability/Sender.java
+++ b/briar-core/src/net/sf/briar/reliability/Sender.java
@@ -11,20 +11,23 @@ import net.sf.briar.api.reliability.WriteHandler;
class Sender {
// All times are in milliseconds
- private static final int MIN_TIMEOUT = 1000;
- private static final int MAX_TIMEOUT = 60 * 1000;
+ private static final int WRITE_TIMEOUT = 5 * 60 * 1000;
+ private static final int MIN_RTO = 1000;
+ private static final int MAX_RTO = 60 * 1000;
private static final int INITIAL_RTT = 0;
private static final int INITIAL_RTT_VAR = 3 * 1000;
+ private static final int MAX_WINDOW_SIZE = 64 * Data.MAX_PAYLOAD_LENGTH;
private final WriteHandler writeHandler;
private final LinkedList<Outstanding> outstanding; // Locking: this
- private int outstandingBytes = 0; // Locking: this
- private int windowSize = Data.MAX_PAYLOAD_LENGTH; // Locking: this
- private int rtt = INITIAL_RTT, rttVar = INITIAL_RTT_VAR; // Locking: this
- private int timeout = rtt + (rttVar << 2); // Locking: this
- private long lastWindowUpdateOrProbe = Long.MAX_VALUE; // Locking: this
- private boolean dataWaiting = false; // Locking: this
+ // All of the following are locking: this
+ private int outstandingBytes = 0;
+ private int windowSize = Data.MAX_PAYLOAD_LENGTH;
+ private int rtt = INITIAL_RTT, rttVar = INITIAL_RTT_VAR;
+ private int rto = rtt + (rttVar << 2);
+ private long lastWindowUpdateOrProbe = Long.MAX_VALUE;
+ private boolean dataWaiting = false;
Sender(WriteHandler writeHandler) {
this.writeHandler = writeHandler;
@@ -62,15 +65,15 @@ class Sender {
it.remove();
outstandingBytes -= o.data.getPayloadLength();
foundIndex = i;
- // Update the round-trip time and retransmission timer
+ // Update the round-trip time and retransmission timeout
if(!o.retransmitted) {
int sample = (int) (now - o.lastTransmitted);
int error = sample - rtt;
rtt += (error >> 3);
rttVar += (Math.abs(error) - rttVar) >> 2;
- timeout = rtt + (rttVar << 2);
- if(timeout < MIN_TIMEOUT) timeout = MIN_TIMEOUT;
- else if(timeout > MAX_TIMEOUT) timeout = MAX_TIMEOUT;
+ rto = rtt + (rttVar << 2);
+ if(rto < MIN_RTO) rto = MIN_RTO;
+ else if(rto > MAX_RTO) rto = MAX_RTO;
}
break;
}
@@ -86,7 +89,7 @@ class Sender {
lastWindowUpdateOrProbe = now;
int oldWindowSize = windowSize;
// Don't accept an unreasonably large window size
- windowSize = Math.min(a.getWindowSize(), Receiver.MAX_WINDOW_SIZE);
+ windowSize = Math.min(a.getWindowSize(), MAX_WINDOW_SIZE);
// If space has become available, notify any waiting writers
if(windowSize > oldWindowSize || foundIndex != -1) notifyAll();
}
@@ -101,22 +104,23 @@ class Sender {
boolean sendProbe = false;
synchronized(this) {
if(outstanding.isEmpty()) {
- if(dataWaiting && now - lastWindowUpdateOrProbe > timeout) {
+ if(dataWaiting && now - lastWindowUpdateOrProbe > rto) {
sendProbe = true;
- timeout <<= 1;
- if(timeout > MAX_TIMEOUT) timeout = MAX_TIMEOUT;
+ rto <<= 1;
+ if(rto > MAX_RTO) rto = MAX_RTO;
}
} else {
Iterator<Outstanding> it = outstanding.iterator();
while(it.hasNext()) {
Outstanding o = it.next();
- if(now - o.lastTransmitted > timeout) {
+ if(now - o.lastTransmitted > rto) {
it.remove();
if(retransmit == null)
retransmit = new ArrayList<Outstanding>();
retransmit.add(o);
- timeout <<= 1;
- if(timeout > MAX_TIMEOUT) timeout = MAX_TIMEOUT;
+ // Update the retransmission timeout
+ rto <<= 1;
+ if(rto > MAX_RTO) rto = MAX_RTO;
}
}
if(retransmit != null) {
@@ -146,10 +150,14 @@ class Sender {
int payloadLength = d.getPayloadLength();
synchronized(this) {
// Wait for space in the window
- while(outstandingBytes + payloadLength >= windowSize) {
+ long now = System.currentTimeMillis(), end = now + WRITE_TIMEOUT;
+ while(now < end && outstandingBytes + payloadLength >= windowSize) {
dataWaiting = true;
- wait();
+ wait(end - now);
+ now = System.currentTimeMillis();
}
+ if(outstandingBytes + payloadLength >= windowSize)
+ throw new IOException("Write timed out");
outstanding.add(new Outstanding(d));
outstandingBytes += payloadLength;
dataWaiting = false;
diff --git a/briar-core/src/net/sf/briar/util/ByteUtils.java b/briar-core/src/net/sf/briar/util/ByteUtils.java
index ec062ec817f245c8e109d31d871cda7df50030a5..d858b8f9b07f28d3eb6e2aefe96459bbc2cf8bdf 100644
--- a/briar-core/src/net/sf/briar/util/ByteUtils.java
+++ b/briar-core/src/net/sf/briar/util/ByteUtils.java
@@ -7,11 +7,6 @@ public class ByteUtils {
*/
public static final int MAX_16_BIT_UNSIGNED = 65535; // 2^16 - 1
- /**
- * The maximum value that can be represented as an unsigned 24-bit integer.
- */
- public static final int MAX_24_BIT_UNSIGNED = 16777215; // 2^24 - 1
-
/**
* The maximum value that can be represented as an unsigned 32-bit integer.
*/
@@ -32,15 +27,6 @@ public class ByteUtils {
b[offset + 1] = (byte) (i & 0xFF);
}
- public static void writeUint24(long i, byte[] b, int offset) {
- if(i < 0L) throw new IllegalArgumentException();
- if(i > MAX_24_BIT_UNSIGNED) throw new IllegalArgumentException();
- if(b.length < offset + 3) throw new IllegalArgumentException();
- b[offset] = (byte) (i >> 16);
- b[offset + 1] = (byte) (i >> 8 & 0xFF);
- b[offset + 2] = (byte) (i & 0xFF);
- }
-
public static void writeUint32(long i, byte[] b, int offset) {
if(i < 0L) throw new IllegalArgumentException();
if(i > MAX_32_BIT_UNSIGNED) throw new IllegalArgumentException();
@@ -56,12 +42,6 @@ public class ByteUtils {
return ((b[offset] & 0xFF) << 8) | (b[offset + 1] & 0xFF);
}
- public static int readUint24(byte[] b, int offset) {
- if(b.length < offset + 3) throw new IllegalArgumentException();
- return ((b[offset] & 0xFF) << 16) | ((b[offset + 1] & 0xFF) << 8)
- | (b[offset + 2] & 0xFF);
- }
-
public static long readUint32(byte[] b, int offset) {
if(b.length < offset + 4) throw new IllegalArgumentException();
return ((b[offset] & 0xFFL) << 24) | ((b[offset + 1] & 0xFFL) << 16)