Fix stall at startup issue

Author: jtraglia

java/src/main/java/com/github/jtraglia/dff/Client.java

@@ -82,13 +82,12 @@ public void connect() throws IOException {
 
         // Read method name (up to 64 bytes)
         ByteBuffer methodBuffer = ByteBuffer.allocate(MAX_METHOD_LENGTH);
-        int methodLength = channel.read(methodBuffer);
-        if (methodLength <= 0) {
-            throw new IOException("Failed to read method name");
-        }
+        // Read method name (exactly 64 bytes, null-padded by server)
+        readFullyBlocking(methodBuffer);
+        methodBuffer.flip();
         // Find null terminator or use full length
-        int actualLength = methodLength;
-        for (int i = 0; i < methodLength; i++) {
+        int actualLength = MAX_METHOD_LENGTH;
+        for (int i = 0; i < MAX_METHOD_LENGTH; i++) {
             if (methodBuffer.get(i) == 0) {
                 actualLength = i;
                 break;

python/dff/server.py

@@ -122,8 +122,12 @@ def _handle_client(self, conn: socket.socket, addr: str) -> None:
             # Send output shared memory ID
             conn.sendall(struct.pack(">I", output_shm.shmid))
 
-            # Send method name
-            conn.sendall(self.method.encode())
+            # Send method name (fixed 64 bytes, null-padded)
+            method_padded = self.method.encode().ljust(64, b'\x00')
+            conn.sendall(method_padded)
+
+            # Set timeout for main loop communication
+            conn.settimeout(60.0)
 
             # Store client
             with self.clients_lock:

rust/src/client.rs

@@ -96,12 +96,13 @@ impl Client {
         }
         self.output_shm = Some(output_shm_ptr as *mut u8);
 
-        // Read method name (up to 64 bytes)
+        // Read method name (exactly 64 bytes, null-padded by server)
         let mut method_bytes = [0u8; 64];
-        let method_length = stream.read(&mut method_bytes).await?;
-        self.method = String::from_utf8_lossy(&method_bytes[..method_length]).to_string();
+        stream.read_exact(&mut method_bytes).await?;
+        let method_end = method_bytes.iter().position(|&b| b == 0).unwrap_or(64);
+        self.method = String::from_utf8_lossy(&method_bytes[..method_end]).to_string();
 
-        log::info!("Connected with fuzzing method: {}", self.method);
+        println!("Connected with fuzzing method: {}", self.method);
 
         self.conn = Some(stream);
         Ok(())