wip

apps/bench.py

@@ -19,6 +19,7 @@ import asyncio
 import enum
 import logging
 import os
+import statistics
 import struct
 import time
 
@@ -194,17 +195,19 @@ def make_sdp_records(channel):
     }
 
 
-def log_stats(title, stats):
+def log_stats(title, stats, precision=2):
     stats_min = min(stats)
     stats_max = max(stats)
-    stats_avg = sum(stats) / len(stats)
+    stats_avg = statistics.mean(stats)
+    stats_stdev = statistics.stdev(stats)
     logging.info(
         color(
             (
                 f'### {title} stats: '
-                f'min={stats_min:.2f}, '
-                f'max={stats_max:.2f}, '
-                f'average={stats_avg:.2f}'
+                f'min={stats_min:.{precision}f}, '
+                f'max={stats_max:.{precision}f}, '
+                f'average={stats_avg:.{precision}f}, '
+                f'stdev={stats_stdev:.{precision}f}'
             ),
             'cyan',
         )
@@ -448,9 +451,9 @@ class Ping:
         self.repeat_delay = repeat_delay
         self.pace = pace
         self.done = asyncio.Event()
-        self.current_packet_index = 0
-        self.ping_sent_time = 0.0
-        self.latencies = []
+        self.ping_times = []
+        self.rtts = []
+        self.next_expected_packet_index = 0
         self.min_stats = []
         self.max_stats = []
         self.avg_stats = []
@@ -477,60 +480,57 @@ class Ping:
             logging.info(color('=== Sending RESET', 'magenta'))
             await self.packet_io.send_packet(bytes([PacketType.RESET]))
 
-            self.current_packet_index = 0
-            self.latencies = []
-            await self.send_next_ping()
+            packet_interval = self.pace / 1000
+            start_time = time.time()
+            self.next_expected_packet_index = 0
+            for i in range(self.tx_packet_count):
+                target_time = start_time + (i * packet_interval)
+                now = time.time()
+                if now < target_time:
+                    await asyncio.sleep(target_time - now)
+
+                packet = struct.pack(
+                    '>bbI',
+                    PacketType.SEQUENCE,
+                    (PACKET_FLAG_LAST if i == self.tx_packet_count - 1 else 0),
+                    i,
+                ) + bytes(self.tx_packet_size - 6)
+                logging.info(color(f'Sending packet {i}', 'yellow'))
+                self.ping_times.append(time.time())
+                await self.packet_io.send_packet(packet)
 
             await self.done.wait()
 
-            min_latency = min(self.latencies)
-            max_latency = max(self.latencies)
-            avg_latency = sum(self.latencies) / len(self.latencies)
+            min_rtt = min(self.rtts)
+            max_rtt = max(self.rtts)
+            avg_rtt = statistics.mean(self.rtts)
+            stdev_rtt = statistics.stdev(self.rtts)
             logging.info(
                 color(
-                    '@@@ Latencies: '
-                    f'min={min_latency:.2f}, '
-                    f'max={max_latency:.2f}, '
-                    f'average={avg_latency:.2f}'
+                    '@@@ RTTs: '
+                    f'min={min_rtt:.2f}, '
+                    f'max={max_rtt:.2f}, '
+                    f'average={avg_rtt:.2f}, '
+                    f'stdev={stdev_rtt:.2f}'
                 )
             )
 
-            self.min_stats.append(min_latency)
-            self.max_stats.append(max_latency)
-            self.avg_stats.append(avg_latency)
+            self.min_stats.append(min_rtt)
+            self.max_stats.append(max_rtt)
+            self.avg_stats.append(avg_rtt)
 
             run_counter = f'[{run + 1} of {self.repeat + 1}]' if self.repeat else ''
             logging.info(color(f'=== {run_counter} Done!', 'magenta'))
 
             if self.repeat:
-                log_stats('Min Latency', self.min_stats)
-                log_stats('Max Latency', self.max_stats)
-                log_stats('Average Latency', self.avg_stats)
+                log_stats('Min RTT', self.min_stats)
+                log_stats('Max RTT', self.max_stats)
+                log_stats('Average RTT', self.avg_stats)
 
         if self.repeat:
             logging.info(color('--- End of runs', 'blue'))
 
-    async def send_next_ping(self):
-        if self.pace:
-            await asyncio.sleep(self.pace / 1000)
-
-        packet = struct.pack(
-            '>bbI',
-            PacketType.SEQUENCE,
-            (
-                PACKET_FLAG_LAST
-                if self.current_packet_index == self.tx_packet_count - 1
-                else 0
-            ),
-            self.current_packet_index,
-        ) + bytes(self.tx_packet_size - 6)
-        logging.info(color(f'Sending packet {self.current_packet_index}', 'yellow'))
-        self.ping_sent_time = time.time()
-        await self.packet_io.send_packet(packet)
-
     def on_packet_received(self, packet):
-        elapsed = time.time() - self.ping_sent_time
-
         try:
             packet_type, packet_data = parse_packet(packet)
         except ValueError:
@@ -542,21 +542,23 @@ class Ping:
             return
 
         if packet_type == PacketType.ACK:
-            latency = elapsed * 1000
-            self.latencies.append(latency)
+            elapsed = time.time() - self.ping_times[packet_index]
+            rtt = elapsed * 1000
+            self.rtts.append(rtt)
             logging.info(
                 color(
-                    f'<<< Received ACK [{packet_index}], latency={latency:.2f}ms',
+                    f'<<< Received ACK [{packet_index}], RTT={rtt:.2f}ms',
                     'green',
                 )
             )
 
-            if packet_index == self.current_packet_index:
-                self.current_packet_index += 1
+            if packet_index == self.next_expected_packet_index:
+                self.next_expected_packet_index += 1
             else:
                 logging.info(
                     color(
-                        f'!!! Unexpected packet, expected {self.current_packet_index} '
+                        f'!!! Unexpected packet, '
+                        f'expected {self.next_expected_packet_index} '
                         f'but received {packet_index}'
                     )
                 )
@@ -565,8 +567,6 @@ class Ping:
             self.done.set()
             return
 
-        AsyncRunner.spawn(self.send_next_ping())
-
 
 # -----------------------------------------------------------------------------
 # Pong
@@ -583,8 +583,11 @@ class Pong:
 
     def reset(self):
         self.expected_packet_index = 0
+        self.receive_times = []
 
     def on_packet_received(self, packet):
+        self.receive_times.append(time.time())
+
         try:
             packet_type, packet_data = parse_packet(packet)
         except ValueError:
@@ -599,10 +602,16 @@ class Pong:
             packet_flags, packet_index = parse_packet_sequence(packet_data)
         except ValueError:
             return
+        interval = (
+            self.receive_times[-1] - self.receive_times[-2]
+            if len(self.receive_times) >= 2
+            else 0
+        )
         logging.info(
             color(
                 f'<<< Received packet {packet_index}: '
-                f'flags=0x{packet_flags:02X}, {len(packet)} bytes',
+                f'flags=0x{packet_flags:02X}, {len(packet)} bytes, '
+                f'interval={interval:.4f}',
                 'green',
             )
         )
@@ -623,8 +632,35 @@ class Pong:
             )
         )
 
-        if packet_flags & PACKET_FLAG_LAST and not self.linger:
-            self.done.set()
+        if packet_flags & PACKET_FLAG_LAST:
+            if len(self.receive_times) >= 3:
+                # Show basic stats
+                intervals = [
+                    self.receive_times[i + 1] - self.receive_times[i]
+                    for i in range(len(self.receive_times) - 1)
+                ]
+                log_stats('Packet intervals', intervals, 3)
+
+                # Show a histogram
+                bin_count = 20
+                bins = [0] * bin_count
+                interval_min = min(intervals)
+                interval_max = max(intervals)
+                interval_range = interval_max - interval_min
+                bin_thresholds = [
+                    interval_min + i * (interval_range / bin_count)
+                    for i in range(bin_count)
+                ]
+                for interval in intervals:
+                    for i in reversed(range(bin_count)):
+                        if interval >= bin_thresholds[i]:
+                            bins[i] += 1
+                            break
+                for i in range(bin_count):
+                    logging.info(f'@@@ >= {bin_thresholds[i]:.4f}: {bins[i]}')
+
+            if not self.linger:
+                self.done.set()
 
     async def run(self):
         await self.done.wait()
@@ -942,9 +978,12 @@ class RfcommClient(StreamedPacketIO):
             channel = await bumble.rfcomm.find_rfcomm_channel_with_uuid(
                 connection, self.uuid
             )
-            logging.info(color(f'@@@ Channel number = {channel}', 'cyan'))
-            if channel == 0:
-                logging.info(color('!!! No RFComm service with this UUID found', 'red'))
+            if channel:
+                logging.info(color(f'@@@ Channel number = {channel}', 'cyan'))
+            else:
+                logging.warning(
+                    color('!!! No RFComm service with this UUID found', 'red')
+                )
                 await connection.disconnect()
                 return
 
@@ -1054,6 +1093,8 @@ class RfcommServer(StreamedPacketIO):
         if self.credits_threshold is not None:
             dlc.rx_credits_threshold = self.credits_threshold
 
+        self.ready.set()
+
     async def drain(self):
         assert self.dlc
         await self.dlc.drain()
@@ -1503,7 +1544,7 @@ def create_role_factory(ctx, default_role):
     '--rfcomm-channel',
     type=int,
     default=DEFAULT_RFCOMM_CHANNEL,
-    help='RFComm channel to use',
+    help='RFComm channel to use (specify 0 for channel discovery via SDP)',
 )
 @click.option(
     '--rfcomm-uuid',
@@ -1743,7 +1784,11 @@ def peripheral(ctx, transport):
 
 
 def main():
-    logging.basicConfig(level=os.environ.get('BUMBLE_LOGLEVEL', 'INFO').upper())
+    logging.basicConfig(
+        level=os.environ.get('BUMBLE_LOGLEVEL', 'INFO').upper(),
+        format="[%(asctime)s.%(msecs)03d] %(levelname)s:%(name)s:%(message)s",
+        datefmt="%H:%M:%S",
+    )
     bench()
 
 

apps/rfcomm_bridge.py

@@ -237,6 +237,7 @@ class ClientBridge:
         address: str,
         tcp_host: str,
         tcp_port: int,
+        authenticate: bool,
         encrypt: bool,
     ):
         self.channel = channel
@@ -245,6 +246,7 @@ class ClientBridge:
         self.address = address
         self.tcp_host = tcp_host
         self.tcp_port = tcp_port
+        self.authenticate = authenticate
         self.encrypt = encrypt
         self.device: Optional[Device] = None
         self.connection: Optional[Connection] = None
@@ -274,6 +276,11 @@ class ClientBridge:
         print(color(f"@@@ Bluetooth connection: {self.connection}", "blue"))
         self.connection.on("disconnection", self.on_disconnection)
 
+        if self.authenticate:
+            print(color("@@@ Authenticating Bluetooth connection", "blue"))
+            await self.connection.authenticate()
+            print(color("@@@ Bluetooth connection authenticated", "blue"))
+
         if self.encrypt:
             print(color("@@@ Encrypting Bluetooth connection", "blue"))
             await self.connection.encrypt()
@@ -491,8 +498,9 @@ def server(context, tcp_host, tcp_port):
 @click.argument("bluetooth-address")
 @click.option("--tcp-host", help="TCP host", default="_")
 @click.option("--tcp-port", help="TCP port", default=DEFAULT_CLIENT_TCP_PORT)
+@click.option("--authenticate", is_flag=True, help="Authenticate the connection")
 @click.option("--encrypt", is_flag=True, help="Encrypt the connection")
-def client(context, bluetooth_address, tcp_host, tcp_port, encrypt):
+def client(context, bluetooth_address, tcp_host, tcp_port, authenticate, encrypt):
     bridge = ClientBridge(
         context.obj["channel"],
         context.obj["uuid"],
@@ -500,6 +508,7 @@ def client(context, bluetooth_address, tcp_host, tcp_port, encrypt):
         bluetooth_address,
         tcp_host,
         tcp_port,
+        authenticate,
         encrypt,
     )
     asyncio.run(run(context.obj["device_config"], context.obj["hci_transport"], bridge))

extras/android/BtBench/app/build.gradle.kts

@@ -60,7 +60,8 @@ dependencies {
     implementation(libs.ui.graphics)
     implementation(libs.ui.tooling.preview)
     implementation(libs.material3)
-    implementation("com.google.android.mobly:mobly-snippet-lib:1.4.0")
+    implementation(libs.mobly.snippet)
+    implementation(libs.androidx.core)
     testImplementation(libs.junit)
     androidTestImplementation(libs.androidx.test.ext.junit)
     androidTestImplementation(libs.espresso.core)

extras/android/BtBench/app/src/main/java/com/github/google/bumble/btbench/AutomationSnippet.java

@@ -0,0 +1,105 @@
+// Copyright 2024 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.github.google.bumble.btbench;
+
+import android.bluetooth.BluetoothAdapter;
+import android.bluetooth.BluetoothManager;
+import android.content.Context;
+import android.renderscript.RSInvalidStateException;
+import android.util.Log;
+
+import com.google.android.mobly.snippet.Snippet;
+import com.google.android.mobly.snippet.rpc.Rpc;
+import androidx.test.core.app.ApplicationProvider;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+
+public class AutomationSnippet implements Snippet {
+    private static final String TAG = "btbench.snippet";
+    private final BluetoothAdapter mBluetoothAdapter;
+    private AppViewModel rfcommServerModel;
+    private RfcommServer rfcommServer;
+    private AppViewModel l2capServerModel;
+    private L2capServer l2capServer;
+
+    public AutomationSnippet() {
+        Context context = ApplicationProvider.getApplicationContext();
+        BluetoothManager bluetoothManager = context.getSystemService(BluetoothManager.class);
+        mBluetoothAdapter = bluetoothManager.getAdapter();
+        if (mBluetoothAdapter == null) {
+            throw new RuntimeException("bluetooth not supported");
+        }
+    }
+
+    private static JSONObject throughputStats(AppViewModel model) throws JSONException {
+        JSONObject result = new JSONObject();
+        JSONObject stats = new JSONObject();
+        result.put("stats", stats);
+        JSONObject throughputStats = new JSONObject();
+        stats.put("throughput", throughputStats);
+        throughputStats.put("average", model.getThroughput());
+        return result;
+    }
+
+    @Rpc(description = "Run an RFComm client throughput test")
+    public JSONObject runRfcommClient(String peerBluetoothAddress, int packetCount, int packetSize) throws JSONException {
+        assert(mBluetoothAdapter != null);
+        AppViewModel model = new AppViewModel();
+        model.setPeerBluetoothAddress(peerBluetoothAddress);
+        model.setSenderPacketCount(packetCount);
+        model.setSenderPacketSize(packetSize);
+
+        //RfcommClient rfCommClient = new RfcommClient(model, mBluetoothAdapter);
+        //rfCommClient.run(true);
+        return throughputStats(model);
+    }
+
+    @Rpc(description = "Run an L2CAP client throughput test")
+    public JSONObject runL2capClient(String peerBluetoothAddress, int psm, boolean use_2m_phy, int packetCount, int packetSize) throws JSONException {
+        assert(mBluetoothAdapter != null);
+        AppViewModel model = new AppViewModel();
+        model.setPeerBluetoothAddress(peerBluetoothAddress);
+        model.setL2capPsm(psm);
+        model.setUse2mPhy(use_2m_phy);
+        model.setSenderPacketCount(packetCount);
+        model.setSenderPacketSize(packetSize);
+
+        Context context = ApplicationProvider.getApplicationContext();
+        //L2capClient l2capClient = new L2capClient(model, mBluetoothAdapter, context);
+        //l2capClient.run(true);
+        return throughputStats(model);
+    }
+
+    @Rpc(description = "Run an RFComm server")
+    public JSONObject runRfcommServer() throws JSONException {
+        assert(mBluetoothAdapter != null);
+        if (rfcommServerModel != null) {
+            rfcommServerModel.abort();
+            rfcommServerModel = null;
+            rfcommServer = null;
+        }
+        rfcommServerModel = new AppViewModel();
+        //rfcommServer = new RfcommServer(rfcommServerModel, mBluetoothAdapter);
+        //rfcommServer.run(true);
+
+        return new JSONObject();
+    }
+
+    @Override
+    public void shutdown() {
+    }
+}

extras/android/BtBench/app/src/main/java/com/github/google/bumble/btbench/IoClient.kt

@@ -0,0 +1,20 @@
+// Copyright 2024 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.github.google.bumble.btbench
+
+interface IoClient {
+    fun run()
+    fun abort()
+}

extras/android/BtBench/app/src/main/java/com/github/google/bumble/btbench/L2capClient.kt

@@ -29,10 +29,11 @@ private val Log = Logger.getLogger("btbench.l2cap-client")
 class L2capClient(
     private val viewModel: AppViewModel,
     private val bluetoothAdapter: BluetoothAdapter,
-    private val context: Context
-) {
+    private val context: Context,
+    private val createIoClient: (packetIo: PacketIO) -> IoClient
+) : Mode {
     @SuppressLint("MissingPermission")
-    fun run() {
+    override fun run(blocking: Boolean) {
         viewModel.running = true
         val addressIsPublic = viewModel.peerBluetoothAddress.endsWith("/P")
         val address = viewModel.peerBluetoothAddress.take(17)
@@ -75,6 +76,7 @@ class L2capClient(
                 ) {
                     if (gatt != null && newState == BluetoothProfile.STATE_CONNECTED) {
                         if (viewModel.use2mPhy) {
+                            Log.info("requesting 2M PHY")
                             gatt.setPreferredPhy(
                                 BluetoothDevice.PHY_LE_2M_MASK,
                                 BluetoothDevice.PHY_LE_2M_MASK,
@@ -95,7 +97,7 @@ class L2capClient(
 
         val socket = remoteDevice.createInsecureL2capChannel(viewModel.l2capPsm)
 
-        val client = SocketClient(viewModel, socket)
-        client.run()
+        val client = SocketClient(viewModel, socket, createIoClient)
+        client.run(blocking)
     }
 }

extras/android/BtBench/app/src/main/java/com/github/google/bumble/btbench/L2capServer.kt

@@ -27,11 +27,15 @@ import kotlin.concurrent.thread
 
 private val Log = Logger.getLogger("btbench.l2cap-server")
 
-class L2capServer(private val viewModel: AppViewModel, private val bluetoothAdapter: BluetoothAdapter) {
+class L2capServer(
+    private val viewModel: AppViewModel,
+    private val bluetoothAdapter: BluetoothAdapter,
+    private val createIoClient: (packetIo: PacketIO) -> IoClient
+) : Mode {
     @SuppressLint("MissingPermission")
-    fun run() {
+    override fun run(blocking: Boolean) {
         // Advertise so that the peer can find us and connect.
-        val callback = object: AdvertiseCallback() {
+        val callback = object : AdvertiseCallback() {
             override fun onStartFailure(errorCode: Int) {
                 Log.warning("failed to start advertising: $errorCode")
             }
@@ -55,7 +59,11 @@ class L2capServer(private val viewModel: AppViewModel, private val bluetoothAdap
         viewModel.l2capPsm = serverSocket.psm
         Log.info("psm = $serverSocket.psm")
 
-        val server = SocketServer(viewModel, serverSocket)
-        server.run({ advertiser.stopAdvertising(callback) }, { advertiser.startAdvertising(advertiseSettings, advertiseData, scanData, callback) })
+        val server = SocketServer(viewModel, serverSocket, createIoClient)
+        server.run(
+            { advertiser.stopAdvertising(callback) },
+            { advertiser.startAdvertising(advertiseSettings, advertiseData, scanData, callback) },
+            blocking
+        )
     }
 }

extras/android/BtBench/app/src/main/java/com/github/google/bumble/btbench/MainActivity.kt

@@ -34,12 +34,15 @@ import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.selection.selectable
+import androidx.compose.foundation.selection.selectableGroup
 import androidx.compose.foundation.text.KeyboardActions
 import androidx.compose.foundation.text.KeyboardOptions
 import androidx.compose.foundation.verticalScroll
 import androidx.compose.material3.Button
 import androidx.compose.material3.Divider
 import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.RadioButton
 import androidx.compose.material3.Slider
 import androidx.compose.material3.Surface
 import androidx.compose.material3.Switch
@@ -54,6 +57,7 @@ import androidx.compose.ui.focus.FocusRequester
 import androidx.compose.ui.focus.focusRequester
 import androidx.compose.ui.platform.LocalFocusManager
 import androidx.compose.ui.platform.LocalSoftwareKeyboardController
+import androidx.compose.ui.semantics.Role
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.text.input.ImeAction
 import androidx.compose.ui.text.input.KeyboardType
@@ -69,6 +73,9 @@ private val Log = Logger.getLogger("bumble.main-activity")
 const val PEER_BLUETOOTH_ADDRESS_PREF_KEY = "peer_bluetooth_address"
 const val SENDER_PACKET_COUNT_PREF_KEY = "sender_packet_count"
 const val SENDER_PACKET_SIZE_PREF_KEY = "sender_packet_size"
+const val SENDER_PACKET_INTERVAL_PREF_KEY = "sender_packet_interval"
+const val SCENARIO_PREF_KEY = "scenario"
+const val MODE_PREF_KEY = "mode"
 
 class MainActivity : ComponentActivity() {
     private val appViewModel = AppViewModel()
@@ -139,10 +146,7 @@ class MainActivity : ComponentActivity() {
             MainView(
                 appViewModel,
                 ::becomeDiscoverable,
-                ::runRfcommClient,
-                ::runRfcommServer,
-                ::runL2capClient,
-                ::runL2capServer,
+                ::runScenario
             )
         }
 
@@ -159,6 +163,10 @@ class MainActivity : ComponentActivity() {
         if (packetSize > 0) {
             appViewModel.senderPacketSize = packetSize
         }
+        val packetInterval = intent.getIntExtra("packet-interval", 0)
+        if (packetInterval > 0) {
+            appViewModel.senderPacketInterval = packetInterval
+        }
         appViewModel.updateSenderPacketSizeSlider()
         intent.getStringExtra("autostart")?.let {
             when (it) {
@@ -172,24 +180,54 @@ class MainActivity : ComponentActivity() {
         }
     }
 
+    private fun runScenario() {
+        if (bluetoothAdapter == null) {
+            return
+        }
+
+        val runner = when (appViewModel.mode) {
+            RFCOMM_CLIENT_MODE -> RfcommClient(appViewModel, bluetoothAdapter!!, ::createIoClient)
+            RFCOMM_SERVER_MODE -> RfcommServer(appViewModel, bluetoothAdapter!!, ::createIoClient)
+            L2CAP_CLIENT_MODE -> L2capClient(
+                appViewModel,
+                bluetoothAdapter!!,
+                baseContext,
+                ::createIoClient
+            )
+            L2CAP_SERVER_MODE -> L2capServer(appViewModel, bluetoothAdapter!!, ::createIoClient)
+            else -> throw IllegalStateException()
+        }
+        runner.run(false)
+    }
+
+    private fun createIoClient(packetIo: PacketIO): IoClient {
+        return when (appViewModel.scenario) {
+            SEND_SCENARIO -> Sender(appViewModel, packetIo)
+            RECEIVE_SCENARIO -> Receiver(appViewModel, packetIo)
+            PING_SCENARIO -> Pinger(appViewModel, packetIo)
+            PONG_SCENARIO -> Ponger(appViewModel, packetIo)
+            else -> throw IllegalStateException()
+        }
+    }
+
     private fun runRfcommClient() {
-        val rfcommClient = bluetoothAdapter?.let { RfcommClient(appViewModel, it) }
-        rfcommClient?.run()
+//        val rfcommClient = bluetoothAdapter?.let { RfcommClient(appViewModel, it) }
+//        rfcommClient?.run()
     }
 
     private fun runRfcommServer() {
-        val rfcommServer = bluetoothAdapter?.let { RfcommServer(appViewModel, it) }
-        rfcommServer?.run()
+//        val rfcommServer = bluetoothAdapter?.let { RfcommServer(appViewModel, it) }
+//        rfcommServer?.run()
     }
 
     private fun runL2capClient() {
-        val l2capClient = bluetoothAdapter?.let { L2capClient(appViewModel, it, baseContext) }
-        l2capClient?.run()
+//        val l2capClient = bluetoothAdapter?.let { L2capClient(appViewModel, it, baseContext) }
+//        l2capClient?.run()
     }
 
     private fun runL2capServer() {
-        val l2capServer = bluetoothAdapter?.let { L2capServer(appViewModel, it) }
-        l2capServer?.run()
+//        val l2capServer = bluetoothAdapter?.let { L2capServer(appViewModel, it) }
+//        l2capServer?.run()
     }
 
     private fun runScan(startScan: Boolean) {
@@ -210,10 +248,7 @@ class MainActivity : ComponentActivity() {
 fun MainView(
     appViewModel: AppViewModel,
     becomeDiscoverable: () -> Unit,
-    runRfcommClient: () -> Unit,
-    runRfcommServer: () -> Unit,
-    runL2capClient: () -> Unit,
-    runL2capServer: () -> Unit,
+    runScenario: () -> Unit,
 ) {
     BTBenchTheme {
         val scrollState = rememberScrollState()
@@ -239,7 +274,9 @@ fun MainView(
                         Text(text = "Peer Bluetooth Address")
                     },
                     value = appViewModel.peerBluetoothAddress,
-                    modifier = Modifier.fillMaxWidth().focusRequester(focusRequester),
+                    modifier = Modifier
+                        .fillMaxWidth()
+                        .focusRequester(focusRequester),
                     keyboardOptions = KeyboardOptions.Default.copy(
                         keyboardType = KeyboardType.Ascii, imeAction = ImeAction.Done
                     ),
@@ -249,14 +286,18 @@ fun MainView(
                     keyboardActions = KeyboardActions(onDone = {
                         keyboardController?.hide()
                         focusManager.clearFocus()
-                    })
+                    }),
+                    enabled = (appViewModel.mode == RFCOMM_CLIENT_MODE) or (appViewModel.mode == L2CAP_CLIENT_MODE)
                 )
                 Divider()
-                TextField(label = {
-                    Text(text = "L2CAP PSM")
-                },
+                TextField(
+                    label = {
+                        Text(text = "L2CAP PSM")
+                    },
                     value = appViewModel.l2capPsm.toString(),
-                    modifier = Modifier.fillMaxWidth().focusRequester(focusRequester),
+                    modifier = Modifier
+                        .fillMaxWidth()
+                        .focusRequester(focusRequester),
                     keyboardOptions = KeyboardOptions.Default.copy(
                         keyboardType = KeyboardType.Number, imeAction = ImeAction.Done
                     ),
@@ -271,7 +312,8 @@ fun MainView(
                     keyboardActions = KeyboardActions(onDone = {
                         keyboardController?.hide()
                         focusManager.clearFocus()
-                    })
+                    }),
+                    enabled = (appViewModel.mode == L2CAP_CLIENT_MODE)
                 )
                 Divider()
                 Slider(
@@ -290,6 +332,32 @@ fun MainView(
                 )
                 Text(text = "Packet Size: " + appViewModel.senderPacketSize.toString())
                 Divider()
+                TextField(
+                    label = {
+                        Text(text = "Packet Interval (ms)")
+                    },
+                    value = appViewModel.senderPacketInterval.toString(),
+                    modifier = Modifier
+                        .fillMaxWidth()
+                        .focusRequester(focusRequester),
+                    keyboardOptions = KeyboardOptions.Default.copy(
+                        keyboardType = KeyboardType.Number, imeAction = ImeAction.Done
+                    ),
+                    onValueChange = {
+                        if (it.isNotEmpty()) {
+                            val interval = it.toIntOrNull()
+                            if (interval != null) {
+                                appViewModel.updateSenderPacketInterval(interval)
+                            }
+                        }
+                    },
+                    keyboardActions = KeyboardActions(onDone = {
+                        keyboardController?.hide()
+                        focusManager.clearFocus()
+                    }),
+                    enabled = (appViewModel.scenario == PING_SCENARIO)
+                )
+                Divider()
                 ActionButton(
                     text = "Become Discoverable", onClick = becomeDiscoverable, true
                 )
@@ -300,25 +368,78 @@ fun MainView(
                     Text(text = "2M PHY")
                     Spacer(modifier = Modifier.padding(start = 8.dp))
                     Switch(
+                        enabled = (appViewModel.mode == L2CAP_CLIENT_MODE || appViewModel.mode == L2CAP_SERVER_MODE),
                         checked = appViewModel.use2mPhy,
                         onCheckedChange = { appViewModel.use2mPhy = it }
                     )
 
                 }
                 Row {
-                    ActionButton(
-                        text = "RFCOMM Client", onClick = runRfcommClient, !appViewModel.running
-                    )
-                    ActionButton(
-                        text = "RFCOMM Server", onClick = runRfcommServer, !appViewModel.running
-                    )
+                    Column(Modifier.selectableGroup()) {
+                        listOf(
+                            RFCOMM_CLIENT_MODE,
+                            RFCOMM_SERVER_MODE,
+                            L2CAP_CLIENT_MODE,
+                            L2CAP_SERVER_MODE
+                        ).forEach { text ->
+                            Row(
+                                Modifier
+                                    .selectable(
+                                        selected = (text == appViewModel.mode),
+                                        onClick = { appViewModel.updateMode(text) },
+                                        role = Role.RadioButton
+                                    )
+                                    .padding(horizontal = 16.dp),
+                                verticalAlignment = Alignment.CenterVertically
+                            ) {
+                                RadioButton(
+                                    selected = (text == appViewModel.mode),
+                                    onClick = null
+                                )
+                                Text(
+                                    text = text,
+                                    style = MaterialTheme.typography.bodyLarge,
+                                    modifier = Modifier.padding(start = 16.dp)
+                                )
+                            }
+                        }
+                    }
+                    Column(Modifier.selectableGroup()) {
+                        listOf(
+                            SEND_SCENARIO,
+                            RECEIVE_SCENARIO,
+                            PING_SCENARIO,
+                            PONG_SCENARIO
+                        ).forEach { text ->
+                            Row(
+                                Modifier
+                                    .selectable(
+                                        selected = (text == appViewModel.scenario),
+                                        onClick = { appViewModel.updateScenario(text) },
+                                        role = Role.RadioButton
+                                    )
+                                    .padding(horizontal = 16.dp),
+                                verticalAlignment = Alignment.CenterVertically
+                            ) {
+                                RadioButton(
+                                    selected = (text == appViewModel.scenario),
+                                    onClick = null
+                                )
+                                Text(
+                                    text = text,
+                                    style = MaterialTheme.typography.bodyLarge,
+                                    modifier = Modifier.padding(start = 16.dp)
+                                )
+                            }
+                        }
+                    }
                 }
                 Row {
                     ActionButton(
-                        text = "L2CAP Client", onClick = runL2capClient, !appViewModel.running
+                        text = "Start", onClick = runScenario, enabled = !appViewModel.running
                     )
                     ActionButton(
-                        text = "L2CAP Server", onClick = runL2capServer, !appViewModel.running
+                        text = "Stop", onClick = appViewModel::abort, enabled = appViewModel.running
                     )
                 }
                 Divider()
@@ -337,9 +458,8 @@ fun MainView(
                 Text(
                     text = "Throughput: ${appViewModel.throughput}"
                 )
-                Divider()
-                ActionButton(
-                    text = "Abort", onClick = appViewModel::abort, appViewModel.running
+                Text(
+                    text = "Stats: ${appViewModel.stats}"
                 )
             }
         }

extras/android/BtBench/app/src/main/java/com/github/google/bumble/btbench/Mode.kt

@@ -0,0 +1,19 @@
+// Copyright 2024 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.github.google.bumble.btbench
+
+interface Mode {
+    fun run(blocking: Boolean)
+}

extras/android/BtBench/app/src/main/java/com/github/google/bumble/btbench/Model.kt

@@ -27,10 +27,23 @@ val DEFAULT_RFCOMM_UUID: UUID = UUID.fromString("E6D55659-C8B4-4B85-96BB-B1143AF
 const val DEFAULT_PEER_BLUETOOTH_ADDRESS = "AA:BB:CC:DD:EE:FF"
 const val DEFAULT_SENDER_PACKET_COUNT = 100
 const val DEFAULT_SENDER_PACKET_SIZE = 1024
+const val DEFAULT_SENDER_PACKET_INTERVAL = 100
 const val DEFAULT_PSM = 128
 
+const val L2CAP_CLIENT_MODE = "L2CAP Client"
+const val L2CAP_SERVER_MODE = "L2CAP Server"
+const val RFCOMM_CLIENT_MODE = "RFCOMM Client"
+const val RFCOMM_SERVER_MODE = "RFCOMM Server"
+
+const val SEND_SCENARIO = "Send"
+const val RECEIVE_SCENARIO = "Receive"
+const val PING_SCENARIO = "Ping"
+const val PONG_SCENARIO = "Pong"
+
 class AppViewModel : ViewModel() {
     private var preferences: SharedPreferences? = null
+    var mode by mutableStateOf(RFCOMM_SERVER_MODE)
+    var scenario by mutableStateOf(RECEIVE_SCENARIO)
     var peerBluetoothAddress by mutableStateOf(DEFAULT_PEER_BLUETOOTH_ADDRESS)
     var l2capPsm by mutableIntStateOf(DEFAULT_PSM)
     var use2mPhy by mutableStateOf(true)
@@ -41,9 +54,11 @@ class AppViewModel : ViewModel() {
     var senderPacketSizeSlider by mutableFloatStateOf(0.0F)
     var senderPacketCount by mutableIntStateOf(DEFAULT_SENDER_PACKET_COUNT)
     var senderPacketSize by mutableIntStateOf(DEFAULT_SENDER_PACKET_SIZE)
+    var senderPacketInterval by mutableIntStateOf(DEFAULT_SENDER_PACKET_INTERVAL)
     var packetsSent by mutableIntStateOf(0)
     var packetsReceived by mutableIntStateOf(0)
     var throughput by mutableIntStateOf(0)
+    var stats by mutableStateOf("")
     var running by mutableStateOf(false)
     var aborter: (() -> Unit)? = null
 
@@ -66,6 +81,21 @@ class AppViewModel : ViewModel() {
             senderPacketSize = savedSenderPacketSize
         }
         updateSenderPacketSizeSlider()
+
+        val savedSenderPacketInterval = preferences.getInt(SENDER_PACKET_INTERVAL_PREF_KEY, -1)
+        if (savedSenderPacketInterval != -1) {
+            senderPacketInterval = savedSenderPacketInterval
+        }
+
+        val savedMode = preferences.getString(MODE_PREF_KEY, null)
+        if (savedMode != null) {
+            mode = savedMode
+        }
+
+        val savedScenario = preferences.getString(SCENARIO_PREF_KEY, null)
+        if (savedScenario != null) {
+            scenario = savedScenario
+        }
     }
 
     fun updatePeerBluetoothAddress(peerBluetoothAddress: String) {
@@ -164,6 +194,30 @@ class AppViewModel : ViewModel() {
         }
     }
 
+    fun updateSenderPacketInterval(senderPacketInterval: Int) {
+        this.senderPacketInterval = senderPacketInterval
+        with(preferences!!.edit()) {
+            putInt(SENDER_PACKET_INTERVAL_PREF_KEY, senderPacketInterval)
+            apply()
+        }
+    }
+
+    fun updateScenario(scenario: String) {
+        this.scenario = scenario
+        with(preferences!!.edit()) {
+            putString(SCENARIO_PREF_KEY, scenario)
+            apply()
+        }
+    }
+
+    fun updateMode(mode: String) {
+        this.mode = mode
+        with(preferences!!.edit()) {
+            putString(MODE_PREF_KEY, mode)
+            apply()
+        }
+    }
+
     fun abort() {
         aborter?.let { it() }
     }

extras/android/BtBench/app/src/main/java/com/github/google/bumble/btbench/Packet.kt

@@ -74,13 +74,13 @@ abstract class PacketSink {
     fun onPacket(packet: Packet) {
         when (packet) {
             is ResetPacket -> onResetPacket()
-            is AckPacket -> onAckPacket()
+            is AckPacket -> onAckPacket(packet)
             is SequencePacket -> onSequencePacket(packet)
         }
     }
 
     abstract fun onResetPacket()
-    abstract fun onAckPacket()
+    abstract fun onAckPacket(packet: AckPacket)
     abstract fun onSequencePacket(packet: SequencePacket)
 }
 

extras/android/BtBench/app/src/main/java/com/github/google/bumble/btbench/Pinger.kt

@@ -0,0 +1,106 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.github.google.bumble.btbench
+
+import java.util.concurrent.Semaphore
+import java.util.logging.Logger
+import kotlin.time.Duration.Companion.milliseconds
+import kotlin.time.TimeSource
+
+private const val DEFAULT_STARTUP_DELAY = 3000
+
+private val Log = Logger.getLogger("btbench.pinger")
+
+class Pinger(private val viewModel: AppViewModel, private val packetIO: PacketIO) : IoClient,
+    PacketSink() {
+    private val pingTimes: ArrayList<TimeSource.Monotonic.ValueTimeMark> = ArrayList()
+    private val rtts: ArrayList<Long> = ArrayList()
+    private val done = Semaphore(0)
+
+    init {
+        packetIO.packetSink = this
+    }
+
+    override fun run() {
+        viewModel.packetsSent = 0
+        viewModel.packetsReceived = 0
+        viewModel.stats = ""
+
+        Log.info("startup delay: $DEFAULT_STARTUP_DELAY")
+        Thread.sleep(DEFAULT_STARTUP_DELAY.toLong());
+        Log.info("running")
+
+        Log.info("sending reset")
+        packetIO.sendPacket(ResetPacket())
+
+        val packetCount = viewModel.senderPacketCount
+        val packetSize = viewModel.senderPacketSize
+
+        val startTime = TimeSource.Monotonic.markNow()
+        for (i in 0..<packetCount) {
+            val now = TimeSource.Monotonic.markNow()
+            val targetTime = startTime + (i * viewModel.senderPacketInterval).milliseconds
+            val delay = targetTime - now
+            if (delay.isPositive()) {
+                Log.info("sleeping ${delay.inWholeMilliseconds} ms")
+                Thread.sleep(delay.inWholeMilliseconds)
+            }
+            pingTimes.add(TimeSource.Monotonic.markNow())
+            packetIO.sendPacket(
+                SequencePacket(
+                    if (i < packetCount - 1) 0 else Packet.LAST_FLAG,
+                    i,
+                    ByteArray(packetSize - 6)
+                )
+            )
+            viewModel.packetsSent = i + 1
+        }
+
+        // Wait for the last ACK
+        Log.info("waiting for last ACK")
+        done.acquire()
+        Log.info("got last ACK")
+    }
+
+    override fun abort() {
+        done.release()
+    }
+
+    override fun onResetPacket() {
+    }
+
+    override fun onAckPacket(packet: AckPacket) {
+        val now = TimeSource.Monotonic.markNow()
+        viewModel.packetsReceived += 1
+        if (packet.sequenceNumber < pingTimes.size) {
+            val rtt = (now - pingTimes[packet.sequenceNumber]).inWholeMilliseconds
+            rtts.add(rtt)
+            Log.info("received ACK ${packet.sequenceNumber}, RTT=$rtt")
+        } else {
+            Log.warning("received ACK with unexpected sequence ${packet.sequenceNumber}")
+        }
+
+        if (packet.flags and Packet.LAST_FLAG != 0) {
+            Log.info("last packet received")
+            val stats = "RTTs: min=${rtts.min()}, max=${rtts.max()}, avg=${rtts.sum() / rtts.size}"
+            Log.info(stats)
+            viewModel.stats = stats
+            done.release()
+        }
+    }
+
+    override fun onSequencePacket(packet: SequencePacket) {
+    }
+}

extras/android/BtBench/app/src/main/java/com/github/google/bumble/btbench/Ponger.kt

@@ -0,0 +1,60 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.github.google.bumble.btbench
+
+import java.util.logging.Logger
+import kotlin.time.TimeSource
+
+private val Log = Logger.getLogger("btbench.receiver")
+
+class Ponger(private val viewModel: AppViewModel, private val packetIO: PacketIO) : IoClient, PacketSink() {
+    private var startTime: TimeSource.Monotonic.ValueTimeMark = TimeSource.Monotonic.markNow()
+    private var lastPacketTime: TimeSource.Monotonic.ValueTimeMark = TimeSource.Monotonic.markNow()
+    private var expectedSequenceNumber: Int = 0
+
+    init {
+        packetIO.packetSink = this
+    }
+
+    override fun run() {}
+
+    override fun abort() {}
+
+    override fun onResetPacket() {
+        startTime = TimeSource.Monotonic.markNow()
+        lastPacketTime = startTime
+        expectedSequenceNumber = 0
+        viewModel.packetsSent = 0
+        viewModel.packetsReceived = 0
+        viewModel.stats = ""
+    }
+
+    override fun onAckPacket(packet: AckPacket) {
+    }
+
+    override fun onSequencePacket(packet: SequencePacket) {
+        val now = TimeSource.Monotonic.markNow()
+        lastPacketTime = now
+        viewModel.packetsReceived += 1
+
+        if (packet.sequenceNumber != expectedSequenceNumber) {
+            Log.warning("unexpected packet sequence number (expected ${expectedSequenceNumber}, got ${packet.sequenceNumber})")
+        }
+        expectedSequenceNumber += 1
+
+        packetIO.sendPacket(AckPacket(packet.flags, packet.sequenceNumber))
+        viewModel.packetsSent += 1
+    }
+}

extras/android/BtBench/app/src/main/java/com/github/google/bumble/btbench/Receiver.kt

@@ -20,7 +20,7 @@ import kotlin.time.TimeSource
 
 private val Log = Logger.getLogger("btbench.receiver")
 
-class Receiver(private val viewModel: AppViewModel, private val packetIO: PacketIO) : PacketSink() {
+class Receiver(private val viewModel: AppViewModel, private val packetIO: PacketIO) : IoClient, PacketSink() {
     private var startTime: TimeSource.Monotonic.ValueTimeMark = TimeSource.Monotonic.markNow()
     private var lastPacketTime: TimeSource.Monotonic.ValueTimeMark = TimeSource.Monotonic.markNow()
     private var bytesReceived = 0
@@ -29,6 +29,10 @@ class Receiver(private val viewModel: AppViewModel, private val packetIO: Packet
         packetIO.packetSink = this
     }
 
+    override fun run() {}
+
+    override fun abort() {}
+
     override fun onResetPacket() {
         startTime = TimeSource.Monotonic.markNow()
         lastPacketTime = startTime
@@ -36,9 +40,10 @@ class Receiver(private val viewModel: AppViewModel, private val packetIO: Packet
         viewModel.throughput = 0
         viewModel.packetsSent = 0
         viewModel.packetsReceived = 0
+        viewModel.stats = ""
     }
 
-    override fun onAckPacket() {
+    override fun onAckPacket(packet: AckPacket) {
 
     }
 

extras/android/BtBench/app/src/main/java/com/github/google/bumble/btbench/RfcommClient.kt

@@ -16,22 +16,24 @@ package com.github.google.bumble.btbench
 
 import android.annotation.SuppressLint
 import android.bluetooth.BluetoothAdapter
-import java.io.IOException
 import java.util.logging.Logger
-import kotlin.concurrent.thread
 
 private val Log = Logger.getLogger("btbench.rfcomm-client")
 
-class RfcommClient(private val viewModel: AppViewModel, val bluetoothAdapter: BluetoothAdapter) {
+class RfcommClient(
+    private val viewModel: AppViewModel,
+    private val bluetoothAdapter: BluetoothAdapter,
+    private val createIoClient: (packetIo: PacketIO) -> IoClient
+) : Mode {
     @SuppressLint("MissingPermission")
-    fun run() {
+    override fun run(blocking: Boolean) {
         val address = viewModel.peerBluetoothAddress.take(17)
         val remoteDevice = bluetoothAdapter.getRemoteDevice(address)
         val socket = remoteDevice.createInsecureRfcommSocketToServiceRecord(
             DEFAULT_RFCOMM_UUID
         )
 
-        val client = SocketClient(viewModel, socket)
-        client.run()
+        val client = SocketClient(viewModel, socket, createIoClient)
+        client.run(blocking)
     }
 }

extras/android/BtBench/app/src/main/java/com/github/google/bumble/btbench/RfcommServer.kt

@@ -22,14 +22,18 @@ import kotlin.concurrent.thread
 
 private val Log = Logger.getLogger("btbench.rfcomm-server")
 
-class RfcommServer(private val viewModel: AppViewModel, val bluetoothAdapter: BluetoothAdapter) {
+class RfcommServer(
+    private val viewModel: AppViewModel,
+    private val bluetoothAdapter: BluetoothAdapter,
+    private val createIoClient: (packetIo: PacketIO) -> IoClient
+) : Mode {
     @SuppressLint("MissingPermission")
-    fun run() {
+    override fun run(blocking: Boolean) {
         val serverSocket = bluetoothAdapter.listenUsingInsecureRfcommWithServiceRecord(
             "BumbleBench", DEFAULT_RFCOMM_UUID
         )
 
-        val server = SocketServer(viewModel, serverSocket)
-        server.run({}, {})
+        val server = SocketServer(viewModel, serverSocket, createIoClient)
+        server.run({}, {}, blocking)
     }
 }

extras/android/BtBench/app/src/main/java/com/github/google/bumble/btbench/Sender.kt

@@ -19,9 +19,12 @@ import java.util.logging.Logger
 import kotlin.time.DurationUnit
 import kotlin.time.TimeSource
 
+private const val DEFAULT_STARTUP_DELAY = 3000
+
 private val Log = Logger.getLogger("btbench.sender")
 
-class Sender(private val viewModel: AppViewModel, private val packetIO: PacketIO) : PacketSink() {
+class Sender(private val viewModel: AppViewModel, private val packetIO: PacketIO) : IoClient,
+    PacketSink() {
     private var startTime: TimeSource.Monotonic.ValueTimeMark = TimeSource.Monotonic.markNow()
     private var bytesSent = 0
     private val done = Semaphore(0)
@@ -30,10 +33,15 @@ class Sender(private val viewModel: AppViewModel, private val packetIO: PacketIO
         packetIO.packetSink = this
     }
 
-    fun run() {
+    override fun run() {
         viewModel.packetsSent = 0
         viewModel.packetsReceived = 0
         viewModel.throughput = 0
+        viewModel.stats = ""
+
+        Log.info("startup delay: $DEFAULT_STARTUP_DELAY")
+        Thread.sleep(DEFAULT_STARTUP_DELAY.toLong());
+        Log.info("running")
 
         Log.info("sending reset")
         packetIO.sendPacket(ResetPacket())
@@ -63,14 +71,14 @@ class Sender(private val viewModel: AppViewModel, private val packetIO: PacketIO
         Log.info("got ACK")
     }
 
-    fun abort() {
+    override fun abort() {
         done.release()
     }
 
     override fun onResetPacket() {
     }
 
-    override fun onAckPacket() {
+    override fun onAckPacket(packet: AckPacket) {
         Log.info("received ACK")
         val elapsed = TimeSource.Monotonic.markNow() - startTime
         val throughput = (bytesSent / elapsed.toDouble(DurationUnit.SECONDS)).toInt()

extras/android/BtBench/app/src/main/java/com/github/google/bumble/btbench/SocketClient.kt

@@ -22,16 +22,18 @@ import kotlin.concurrent.thread
 
 private val Log = Logger.getLogger("btbench.socket-client")
 
-private const val DEFAULT_STARTUP_DELAY = 3000
-
-class SocketClient(private val viewModel: AppViewModel, private val socket: BluetoothSocket) {
+class SocketClient(
+    private val viewModel: AppViewModel,
+    private val socket: BluetoothSocket,
+    private val createIoClient: (packetIo: PacketIO) -> IoClient
+) {
     @SuppressLint("MissingPermission")
-    fun run() {
+    fun run(blocking: Boolean = false) {
         viewModel.running = true
         val socketDataSink = SocketDataSink(socket)
         val streamIO = StreamedPacketIO(socketDataSink)
         val socketDataSource = SocketDataSource(socket, streamIO::onData)
-        val sender = Sender(viewModel, streamIO)
+        val ioClient = createIoClient(streamIO)
 
         fun cleanup() {
             socket.close()
@@ -39,9 +41,9 @@ class SocketClient(private val viewModel: AppViewModel, private val socket: Blue
             viewModel.running = false
         }
 
-        thread(name = "SocketClient") {
+        val clientThread = thread(name = "SocketClient") {
             viewModel.aborter = {
-                sender.abort()
+                ioClient.abort()
                 socket.close()
             }
             Log.info("connecting to remote")
@@ -54,22 +56,26 @@ class SocketClient(private val viewModel: AppViewModel, private val socket: Blue
             }
             Log.info("connected")
 
-            thread {
+            val sourceThread = thread {
                 socketDataSource.receive()
                 socket.close()
-                sender.abort()
+                ioClient.abort()
             }
 
-            Log.info("Startup delay: $DEFAULT_STARTUP_DELAY")
-            Thread.sleep(DEFAULT_STARTUP_DELAY.toLong());
-            Log.info("Starting to send")
-
             try {
-                sender.run()
+                ioClient.run()
             } catch (error: IOException) {
                 Log.info("run ended abruptly")
             }
+
+            Log.info("waiting for source thread to finish")
+            sourceThread.join()
+
             cleanup()
         }
+
+        if (blocking) {
+            clientThread.join()
+        }
     }
 }

extras/android/BtBench/app/src/main/java/com/github/google/bumble/btbench/SocketServer.kt

@@ -21,8 +21,12 @@ import kotlin.concurrent.thread
 
 private val Log = Logger.getLogger("btbench.socket-server")
 
-class SocketServer(private val viewModel: AppViewModel, private val serverSocket: BluetoothServerSocket) {
-    fun run(onConnected: () -> Unit, onDisconnected: () -> Unit) {
+class SocketServer(
+    private val viewModel: AppViewModel,
+    private val serverSocket: BluetoothServerSocket,
+    private val createIoClient: (packetIo: PacketIO) -> IoClient
+) {
+    fun run(onConnected: () -> Unit, onDisconnected: () -> Unit, blocking: Boolean = false) {
         var aborted = false
         viewModel.running = true
 
@@ -31,7 +35,7 @@ class SocketServer(private val viewModel: AppViewModel, private val serverSocket
             viewModel.running = false
         }
 
-        thread(name = "SocketServer") {
+        val serverThread = thread(name = "SocketServer") {
             while (!aborted) {
                 viewModel.aborter = {
                     serverSocket.close()
@@ -46,6 +50,8 @@ class SocketServer(private val viewModel: AppViewModel, private val serverSocket
                     return@thread
                 }
                 Log.info("got connection from ${socket.remoteDevice.address}")
+                Log.info("maxReceivePacketSize=${socket.maxReceivePacketSize}")
+                Log.info("maxTransmitPacketSize=${socket.maxTransmitPacketSize}")
                 onConnected()
 
                 viewModel.aborter = {
@@ -57,11 +63,15 @@ class SocketServer(private val viewModel: AppViewModel, private val serverSocket
                 val socketDataSink = SocketDataSink(socket)
                 val streamIO = StreamedPacketIO(socketDataSink)
                 val socketDataSource = SocketDataSource(socket, streamIO::onData)
-                val receiver = Receiver(viewModel, streamIO)
+                val ioClient = createIoClient(streamIO)
                 socketDataSource.receive()
                 socket.close()
             }
             cleanup()
         }
+
+        if (blocking) {
+            serverThread.join()
+        }
     }
 }

extras/android/BtBench/gradle/libs.versions.toml

@@ -1,5 +1,5 @@
 [versions]
-agp = "8.2.0"
+agp = "8.4.0"
 kotlin = "1.9.0"
 core-ktx = "1.12.0"
 junit = "4.13.2"
@@ -8,6 +8,8 @@ espresso-core = "3.5.1"
 lifecycle-runtime-ktx = "2.6.2"
 activity-compose = "1.7.2"
 compose-bom = "2023.08.00"
+mobly-snippet = "1.4.0"
+core = "1.6.1"
 
 [libraries]
 core-ktx = { group = "androidx.core", name = "core-ktx", version.ref = "core-ktx" }
@@ -24,6 +26,8 @@ ui-tooling-preview = { group = "androidx.compose.ui", name = "ui-tooling-preview
 ui-test-manifest = { group = "androidx.compose.ui", name = "ui-test-manifest" }
 ui-test-junit4 = { group = "androidx.compose.ui", name = "ui-test-junit4" }
 material3 = { group = "androidx.compose.material3", name = "material3" }
+mobly-snippet = { group = "com.google.android.mobly", name = "mobly-snippet-lib", version.ref = "mobly.snippet" }
+androidx-core = { group = "androidx.test", name = "core", version.ref = "core" }
 
 [plugins]
 androidApplication = { id = "com.android.application", version.ref = "agp" }

extras/android/BtBench/gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 #Wed Oct 25 07:40:52 PDT 2023
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.4-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.6-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists