Roll forward to cl/328359974

Change-Id: If2b57ecc852aecf7dea454648f485fd7c08e72a9

cpp/platform_v2/impl/g3/BUILD

@@ -39,12 +39,14 @@ cc_library(
     name = "comm",
     testonly = True,
     srcs = [
+        "ble.cc",
         "bluetooth_adapter.cc",
         "bluetooth_classic.cc",
         "webrtc.cc",
         "wifi_lan.cc",
     ],
     hdrs = [
+        "ble.h",
         "bluetooth_adapter.h",
         "bluetooth_classic.h",
         "webrtc.h",
@@ -76,9 +78,7 @@ cc_library(
     srcs = [
         "crypto.cc",
     ],
-    visibility = [
-        "//platform_v2/g3:__pkg__",
-    ],
+    visibility = ["//visibility:private"],
     deps = [
         "//platform_v2/api:types",
         "//platform_v2/base",
@@ -94,7 +94,6 @@ cc_library(
         "platform.cc",
     ],
     visibility = [
-        "//googlemac/iPhone/Shared/Nearby/Connections:__subpackages__",
         "//core_v2:__subpackages__",
         "//platform_v2:__subpackages__",
     ],

cpp/platform_v2/impl/g3/ble.cc

@@ -0,0 +1,341 @@
+#include "platform_v2/impl/g3/ble.h"
+
+#include <iostream>
+#include <memory>
+#include <string>
+
+#include "platform_v2/api/ble.h"
+#include "platform_v2/base/logging.h"
+#include "platform_v2/base/medium_environment.h"
+#include "absl/synchronization/mutex.h"
+
+namespace location {
+namespace nearby {
+namespace g3 {
+
+BleSocket::~BleSocket() {
+  absl::MutexLock lock(&mutex_);
+  DoClose();
+}
+
+void BleSocket::Connect(BleSocket& other) {
+  absl::MutexLock lock(&mutex_);
+  remote_socket_ = &other;
+  input_ = other.output_;
+}
+
+InputStream& BleSocket::GetInputStream() {
+  auto* remote_socket = GetRemoteSocket();
+  CHECK(remote_socket != nullptr);
+  return remote_socket->GetLocalInputStream();
+}
+
+OutputStream& BleSocket::GetOutputStream() {
+  return GetLocalOutputStream();
+}
+
+BleSocket* BleSocket::GetRemoteSocket() {
+  absl::MutexLock lock(&mutex_);
+  return remote_socket_;
+}
+
+bool BleSocket::IsConnected() const {
+  absl::MutexLock lock(&mutex_);
+  return IsConnectedLocked();
+}
+
+bool BleSocket::IsClosed() const {
+  absl::MutexLock lock(&mutex_);
+  return closed_;
+}
+
+Exception BleSocket::Close() {
+  absl::MutexLock lock(&mutex_);
+  DoClose();
+  return {Exception::kSuccess};
+}
+
+BlePeripheral* BleSocket::GetRemotePeripheral() {
+  absl::MutexLock lock(&mutex_);
+  return peripheral_;
+}
+
+void BleSocket::DoClose() {
+  if (!closed_) {
+    remote_socket_ = nullptr;
+    output_->GetOutputStream().Close();
+    output_->GetInputStream().Close();
+    if (IsConnectedLocked()) {
+      input_->GetOutputStream().Close();
+      input_->GetInputStream().Close();
+    }
+    closed_ = true;
+  }
+}
+
+bool BleSocket::IsConnectedLocked() const { return input_ != nullptr; }
+
+InputStream& BleSocket::GetLocalInputStream() {
+  absl::MutexLock lock(&mutex_);
+  return output_->GetInputStream();
+}
+
+OutputStream& BleSocket::GetLocalOutputStream() {
+  absl::MutexLock lock(&mutex_);
+  return output_->GetOutputStream();
+}
+
+std::unique_ptr<api::BleSocket> BleServerSocket::Accept(
+    BlePeripheral* peripheral) {
+  absl::MutexLock lock(&mutex_);
+  if (closed_) return {};
+  while (pending_sockets_.empty()) {
+    cond_.Wait(&mutex_);
+    if (closed_) break;
+  }
+  if (closed_) return {};
+  auto* remote_socket =
+      pending_sockets_.extract(pending_sockets_.begin()).value();
+  CHECK(remote_socket);
+  auto local_socket = std::make_unique<BleSocket>(peripheral);
+  local_socket->Connect(*remote_socket);
+  remote_socket->Connect(*local_socket);
+  cond_.SignalAll();
+  return local_socket;
+}
+
+bool BleServerSocket::Connect(BleSocket& socket) {
+  absl::MutexLock lock(&mutex_);
+  if (closed_) return false;
+  if (socket.IsConnected()) {
+    NEARBY_LOG(ERROR,
+               "Failed to connect to Ble server socket: already connected");
+    return true;  // already connected.
+  }
+  // add client socket to the pending list
+  pending_sockets_.emplace(&socket);
+  cond_.SignalAll();
+  while (!socket.IsConnected()) {
+    cond_.Wait(&mutex_);
+    if (closed_) return false;
+  }
+  return true;
+}
+
+void BleServerSocket::SetCloseNotifier(std::function<void()> notifier) {
+  absl::MutexLock lock(&mutex_);
+  close_notifier_ = std::move(notifier);
+}
+
+BleServerSocket::~BleServerSocket() {
+  absl::MutexLock lock(&mutex_);
+  DoClose();
+}
+
+Exception BleServerSocket::Close() {
+  absl::MutexLock lock(&mutex_);
+  return DoClose();
+}
+
+Exception BleServerSocket::DoClose() {
+  bool should_notify = !closed_;
+  closed_ = true;
+  if (should_notify) {
+    cond_.SignalAll();
+    if (close_notifier_) {
+      auto notifier = std::move(close_notifier_);
+      mutex_.Unlock();
+      // Notifier may contain calls to public API, and may cause deadlock, if
+      // mutex_ is held during the call.
+      notifier();
+      mutex_.Lock();
+    }
+  }
+  return {Exception::kSuccess};
+}
+
+BleMedium::BleMedium(api::BluetoothAdapter& adapter)
+    : adapter_(static_cast<BluetoothAdapter*>(&adapter)) {
+  adapter_->SetBleMedium(this);
+  auto& env = MediumEnvironment::Instance();
+  env.RegisterBleMedium(*this);
+}
+
+BleMedium::~BleMedium() {
+  adapter_->SetBleMedium(nullptr);
+  auto& env = MediumEnvironment::Instance();
+  env.UnregisterBleMedium(*this);
+
+  StopAdvertising(advertising_info_.service_id);
+  StopScanning(scanning_info_.service_id);
+
+  accept_loops_runner_.Shutdown();
+  NEARBY_LOG(INFO, "BleMedium dtor advertising_accept_thread_running_ = %d",
+             acceptance_thread_running_.load());
+  // If acceptance thread is still running, wait to finish.
+  if (acceptance_thread_running_) {
+    while (acceptance_thread_running_) {
+      CountDownLatch latch(1);
+      close_accept_loops_runner_.Execute([&latch]() { latch.CountDown(); });
+      latch.Await();
+    }
+  }
+}
+
+bool BleMedium::StartAdvertising(const std::string& service_id,
+                                 const ByteArray& advertisement_bytes) {
+  NEARBY_LOGS(INFO) << "G3 Ble StartAdvertising: service_id=" << service_id
+                    << ", advertisement bytes=" << advertisement_bytes.data()
+                    << "(" << advertisement_bytes.size() << ")";
+  auto& env = MediumEnvironment::Instance();
+  auto& peripheral = adapter_->GetPeripheral();
+  peripheral.SetAdvertisementBytes(service_id, advertisement_bytes);
+  env.UpdateBleMediumForAdvertising(*this, peripheral, service_id, true);
+
+  absl::MutexLock lock(&mutex_);
+  if (server_socket_ != nullptr) server_socket_.release();
+  server_socket_ = std::make_unique<BleServerSocket>();
+
+  acceptance_thread_running_.exchange(true);
+  accept_loops_runner_.Execute([&env, this, service_id]() mutable {
+    if (!accept_loops_runner_.InShutdown()) {
+      while (true) {
+        auto client_socket =
+            server_socket_->Accept(&(this->adapter_->GetPeripheral()));
+        if (client_socket == nullptr) break;
+        env.CallBleAcceptedConnectionCallback(*this, *(client_socket.release()),
+                                              service_id);
+      }
+    }
+    acceptance_thread_running_.exchange(false);
+  });
+  advertising_info_.service_id = service_id;
+  return true;
+}
+
+bool BleMedium::StopAdvertising(const std::string& service_id) {
+  NEARBY_LOGS(INFO) << "G3 Ble StopAdvertising: service_id=" << service_id;
+  {
+    absl::MutexLock lock(&mutex_);
+    if (advertising_info_.Empty()) {
+      NEARBY_LOGS(INFO) << "G3 Ble StopAdvertising: Can't stop advertising "
+                           "because we never started advertising.";
+      return false;
+    }
+    advertising_info_.Clear();
+  }
+
+  auto& env = MediumEnvironment::Instance();
+  env.UpdateBleMediumForAdvertising(*this, adapter_->GetPeripheral(),
+                                    service_id, false);
+  accept_loops_runner_.Shutdown();
+  if (server_socket_ == nullptr) {
+    NEARBY_LOGS(ERROR) << "G3 Ble StopAdvertising: Failed to find Ble Server "
+                          "socket: service_id="
+                       << service_id;
+    // Fall through for server socket not found.
+    return true;
+  }
+
+  if (!server_socket_->Close().Ok()) {
+    NEARBY_LOGS(INFO)
+        << "G3 Ble StopAdvertising: Failed to close Ble server socket for "
+        << service_id;
+    return false;
+  }
+  return true;
+}
+
+bool BleMedium::StartScanning(const std::string& service_id,
+                              DiscoveredPeripheralCallback callback) {
+  NEARBY_LOGS(INFO) << "G3 Ble StartScanning: service_id=" << service_id;
+  auto& env = MediumEnvironment::Instance();
+  env.UpdateBleMediumForScanning(*this, service_id, std::move(callback), true);
+  {
+    absl::MutexLock lock(&mutex_);
+    scanning_info_.service_id = service_id;
+  }
+  return true;
+}
+
+bool BleMedium::StopScanning(const std::string& service_id) {
+  NEARBY_LOGS(INFO) << "G3 Ble StopScanning: service_id=" << service_id;
+  {
+    absl::MutexLock lock(&mutex_);
+    if (scanning_info_.Empty()) {
+      NEARBY_LOGS(INFO) << "G3 Ble StopDiscovery: Can't stop scanning because "
+                           "we never started scanning.";
+      return false;
+    }
+    scanning_info_.Clear();
+  }
+
+  auto& env = MediumEnvironment::Instance();
+  env.UpdateBleMediumForScanning(*this, service_id, {}, false);
+  return true;
+}
+
+bool BleMedium::StartAcceptingConnections(const std::string& service_id,
+                                          AcceptedConnectionCallback callback) {
+  NEARBY_LOGS(INFO) << "G3 Ble StartAcceptingConnections: service_id="
+                    << service_id;
+  auto& env = MediumEnvironment::Instance();
+  env.UpdateBleMediumForAcceptedConnection(*this, service_id, callback);
+  return true;
+}
+
+bool BleMedium::StopAcceptingConnections(const std::string& service_id) {
+  NEARBY_LOGS(INFO) << "G3 Ble StopAcceptingConnections: service_id="
+                    << service_id;
+  auto& env = MediumEnvironment::Instance();
+  env.UpdateBleMediumForAcceptedConnection(*this, service_id, {});
+  return true;
+}
+
+std::unique_ptr<api::BleSocket> BleMedium::Connect(
+    api::BlePeripheral& remote_peripheral, const std::string& service_id) {
+  NEARBY_LOG(INFO,
+             "G3 Ble Connect [self]: medium=%p, adapter=%p, peripheral=%p, "
+             "service_id=%s",
+             this, &GetAdapter(), &GetAdapter().GetPeripheral(),
+             service_id.c_str());
+  // First, find an instance of remote medium, that exposed this peripheral.
+  auto& adapter = static_cast<BlePeripheral&>(remote_peripheral).GetAdapter();
+  auto* medium = static_cast<BleMedium*>(adapter.GetBleMedium());
+
+  if (!medium) return {};  // Can't find medium. Bail out.
+
+  BleServerSocket* remote_server_socket = nullptr;
+  NEARBY_LOG(INFO,
+             "G3 Ble Connect [peer]: medium=%p, adapter=%p, peripheral=%p, "
+             "service_id=%s",
+             medium, &adapter, &remote_peripheral, service_id.c_str());
+  // Then, find our server socket context in this medium.
+  {
+    absl::MutexLock medium_lock(&medium->mutex_);
+    remote_server_socket = medium->server_socket_.get();
+    if (remote_server_socket == nullptr) {
+      NEARBY_LOGS(ERROR)
+          << "G3 Ble Connect: Failed to find Ble Server socket: service_id="
+          << service_id;
+      return {};
+    }
+  }
+
+  BlePeripheral peripheral = static_cast<BlePeripheral&>(remote_peripheral);
+  auto socket = std::make_unique<BleSocket>(&peripheral);
+  // Finally, Request to connect to this socket.
+  if (!remote_server_socket->Connect(*socket)) {
+    NEARBY_LOGS(ERROR) << "G3 Ble Connect: Failed to connect to existing Ble "
+                          "Server socket: service_id="
+                       << service_id;
+    return {};
+  }
+
+  NEARBY_LOG(INFO, "G3 Ble Connect: connected: socket=%p", socket.get());
+  return socket;
+}
+
+}  // namespace g3
+}  // namespace nearby
+}  // namespace location

cpp/platform_v2/impl/g3/ble.h

@@ -0,0 +1,213 @@
+#ifndef PLATFORM_V2_IMPL_G3_BLE_H_
+#define PLATFORM_V2_IMPL_G3_BLE_H_
+
+#include <memory>
+#include <string>
+
+#include "platform_v2/api/ble.h"
+#include "platform_v2/base/byte_array.h"
+#include "platform_v2/base/input_stream.h"
+#include "platform_v2/base/output_stream.h"
+#include "platform_v2/impl/g3/bluetooth_adapter.h"
+#include "platform_v2/impl/g3/bluetooth_classic.h"
+#include "platform_v2/impl/g3/multi_thread_executor.h"
+#include "platform_v2/impl/g3/pipe.h"
+#include "absl/container/flat_hash_map.h"
+#include "absl/container/flat_hash_set.h"
+#include "absl/strings/escaping.h"
+#include "absl/synchronization/mutex.h"
+
+namespace location {
+namespace nearby {
+namespace g3 {
+
+class BleMedium;
+
+class BleSocket : public api::BleSocket {
+ public:
+  BleSocket() = default;
+  explicit BleSocket(BlePeripheral* peripheral) : peripheral_(peripheral) {}
+  ~BleSocket() override;
+
+  // Connect to another BleSocket, to form a functional low-level channel.
+  // from this point on, and until Close is called, connection exists.
+  void Connect(BleSocket& other) ABSL_LOCKS_EXCLUDED(mutex_);
+
+  // Returns the InputStream of this connected BleSocket.
+  InputStream& GetInputStream() override ABSL_LOCKS_EXCLUDED(mutex_);
+
+  // Returns the OutputStream of this connected BleSocket.
+  // This stream is for local side to write.
+  OutputStream& GetOutputStream() override ABSL_LOCKS_EXCLUDED(mutex_);
+
+  // Returns address of a remote BleSocket or nullptr.
+  BleSocket* GetRemoteSocket() ABSL_LOCKS_EXCLUDED(mutex_);
+
+  // Returns true if connection exists to the (possibly closed) remote socket.
+  bool IsConnected() const ABSL_LOCKS_EXCLUDED(mutex_);
+
+  // Returns true if socket is closed.
+  bool IsClosed() const ABSL_LOCKS_EXCLUDED(mutex_);
+
+  // Returns Exception::kIo on error, Exception::kSuccess otherwise.
+  Exception Close() override ABSL_LOCKS_EXCLUDED(mutex_);
+
+  // Returns valid BlePeripheral pointer if there is a connection, and
+  // nullptr otherwise.
+  BlePeripheral* GetRemotePeripheral() override
+      ABSL_LOCKS_EXCLUDED(mutex_);
+
+ private:
+  void DoClose() ABSL_EXCLUSIVE_LOCKS_REQUIRED(mutex_);
+
+  // Returns true if connection exists to the (possibly closed) remote socket.
+  bool IsConnectedLocked() const ABSL_EXCLUSIVE_LOCKS_REQUIRED(mutex_);
+
+  // Returns InputStream of our side of a connection.
+  // This is what the remote side is supposed to read from.
+  // This is a helper for GetInputStream() method.
+  InputStream& GetLocalInputStream() ABSL_LOCKS_EXCLUDED(mutex_);
+
+  // Returns OutputStream of our side of a connection.
+  // This is what the local size is supposed to write to.
+  // This is a helper for GetOutputStream() method.
+  OutputStream& GetLocalOutputStream() ABSL_LOCKS_EXCLUDED(mutex_);
+
+  // Output pipe is initialized by constructor, it remains always valid, until
+  // it is closed. it represents output part of a local socket. Input part of a
+  // local socket comes from the peer socket, after connection.
+  std::shared_ptr<Pipe> output_ {new Pipe};
+  std::shared_ptr<Pipe> input_;
+  mutable absl::Mutex mutex_;
+  BlePeripheral* peripheral_;
+  BleSocket* remote_socket_ ABSL_GUARDED_BY(mutex_) = nullptr;
+  bool closed_ ABSL_GUARDED_BY(mutex_) = false;
+};
+
+class BleServerSocket {
+ public:
+  ~BleServerSocket();
+
+  // Blocks until either:
+  // - at least one incoming connection request is available, or
+  // - ServerSocket is closed.
+  // On success, returns connected socket, ready to exchange data.
+  // Returns nullptr on error.
+  // Once error is reported, it is permanent, and ServerSocket has to be closed.
+  //
+  // Called by the server side of a connection.
+  // Returns BleSocket to the server side.
+  // If not null, returned socket is connected to its remote (client-side) peer.
+  std::unique_ptr<api::BleSocket> Accept(BlePeripheral* peripheral)
+      ABSL_LOCKS_EXCLUDED(mutex_);
+
+  // Blocks until either:
+  // - connection is available, or
+  // - server socket is closed, or
+  // - error happens.
+  //
+  // Called by the client side of a connection.
+  // Returns true, if socket is successfully connected.
+  bool Connect(BleSocket& socket) ABSL_LOCKS_EXCLUDED(mutex_);
+
+  // Called by the server side of a connection before passing ownership of
+  // BleServerSocker to user, to track validity of a pointer to this
+  // server socket,
+  void SetCloseNotifier(std::function<void()> notifier)
+      ABSL_LOCKS_EXCLUDED(mutex_);
+
+  // Returns Exception::kIo on error, Exception::kSuccess otherwise.
+  // Calls close_notifier if it was previously set, and marks socket as closed.
+  Exception Close() ABSL_LOCKS_EXCLUDED(mutex_);
+
+ private:
+  Exception DoClose() ABSL_EXCLUSIVE_LOCKS_REQUIRED(mutex_);
+
+  absl::Mutex mutex_;
+  absl::CondVar cond_;
+  absl::flat_hash_set<BleSocket*> pending_sockets_ ABSL_GUARDED_BY(mutex_);
+  std::function<void()> close_notifier_ ABSL_GUARDED_BY(mutex_);
+  bool closed_ ABSL_GUARDED_BY(mutex_) = false;
+};
+
+// Container of operations that can be performed over the BLE medium.
+class BleMedium : public api::BleMedium {
+ public:
+  explicit BleMedium(api::BluetoothAdapter& adapter);
+  ~BleMedium() override;
+
+  // Returns true once the Ble advertising has been initiated.
+  bool StartAdvertising(const std::string& service_id,
+                        const ByteArray& advertisement_bytes) override
+      ABSL_LOCKS_EXCLUDED(mutex_);
+  bool StopAdvertising(const std::string& service_id) override
+      ABSL_LOCKS_EXCLUDED(mutex_);
+
+  // Returns true once the Ble scanning has been initiated.
+  bool StartScanning(const std::string& service_id,
+                     DiscoveredPeripheralCallback callback) override
+      ABSL_LOCKS_EXCLUDED(mutex_);
+
+  // Returns true once Ble scanning for service_id is well and truly
+  // stopped; after this returns, there must be no more invocations of the
+  // DiscoveredPeripheralCallback passed in to StartScanning() for service_id.
+  bool StopScanning(const std::string& service_id) override
+      ABSL_LOCKS_EXCLUDED(mutex_);
+
+  // Returns true once Ble socket connection requests to service_id can be
+  // accepted.
+  bool StartAcceptingConnections(const std::string& service_id,
+                                 AcceptedConnectionCallback callback)
+      override ABSL_LOCKS_EXCLUDED(mutex_);
+  bool StopAcceptingConnections(const std::string& service_id) override
+      ABSL_LOCKS_EXCLUDED(mutex_);
+
+  // Connects to existing remote Ble peripheral.
+  //
+  // On success, returns a new BleSocket.
+  // On error, returns nullptr.
+  std::unique_ptr<api::BleSocket> Connect(
+      api::BlePeripheral& remote_peripheral,
+      const std::string& service_id) override ABSL_LOCKS_EXCLUDED(mutex_);
+
+  BluetoothAdapter& GetAdapter() { return *adapter_; }
+
+ private:
+  static constexpr int kMaxConcurrentAcceptLoops = 5;
+
+  struct AdvertisingInfo {
+    bool Empty() const { return service_id.empty(); }
+    void Clear() { service_id.clear(); }
+
+    std::string service_id;
+  };
+
+  struct ScanningInfo {
+    bool Empty() const { return service_id.empty(); }
+    void Clear() { service_id.clear(); }
+
+    std::string service_id;
+  };
+
+  absl::Mutex mutex_;
+  BluetoothAdapter* adapter_;  // Our device adapter; read-only.
+
+  // A thread pool dedicated to running all the accept loops from
+  // StartAdvertising().
+  MultiThreadExecutor accept_loops_runner_{kMaxConcurrentAcceptLoops};
+  std::atomic_bool acceptance_thread_running_ = false;
+
+  // A thread pool dedicated to wait to complete the accept_loops_runner_.
+  MultiThreadExecutor close_accept_loops_runner_{kMaxConcurrentAcceptLoops};
+
+  // A server socket is established when start advertising.
+  std::unique_ptr<BleServerSocket> server_socket_;
+  AdvertisingInfo advertising_info_ ABSL_GUARDED_BY(mutex_);
+  ScanningInfo scanning_info_ ABSL_GUARDED_BY(mutex_);
+};
+
+}  // namespace g3
+}  // namespace nearby
+}  // namespace location
+
+#endif  // PLATFORM_V2_IMPL_G3_BLE_H_

cpp/platform_v2/impl/g3/bluetooth_adapter.cc

@@ -3,21 +3,57 @@
 #include <string>
 
 #include "platform_v2/base/medium_environment.h"
+#include "platform_v2/base/prng.h"
 #include "platform_v2/impl/g3/bluetooth_classic.h"
 
 namespace location {
 namespace nearby {
 namespace g3 {
 
+BlePeripheral::BlePeripheral(BluetoothAdapter* adapter) : adapter_(*adapter) {}
+
+std::string BlePeripheral::GetName() const { return adapter_.GetName(); }
+
+ByteArray BlePeripheral::GetAdvertisementBytes(
+    const std::string& service_id) const {
+  return advertisement_bytes_;
+}
+
+void BlePeripheral::SetAdvertisementBytes(
+    const std::string& service_id, const ByteArray& advertisement_bytes) {
+  advertisement_bytes_ = advertisement_bytes;
+}
+
 BluetoothDevice::BluetoothDevice(BluetoothAdapter* adapter)
     : adapter_(*adapter) {}
 
 std::string BluetoothDevice::GetName() const { return adapter_.GetName(); }
+std::string BluetoothDevice::GetMacAddress() const {
+  return adapter_.GetMacAddress();
+}
+
+BluetoothAdapter::BluetoothAdapter() {
+  std::string mac_address;
+  mac_address.resize(6);
+  int64_t raw_mac_addr = Prng().NextInt64();
+  mac_address[0] = static_cast<char>(raw_mac_addr >> 40);
+  mac_address[1] = static_cast<char>(raw_mac_addr >> 32);
+  mac_address[2] = static_cast<char>(raw_mac_addr >> 24);
+  mac_address[3] = static_cast<char>(raw_mac_addr >> 16);
+  mac_address[4] = static_cast<char>(raw_mac_addr >> 8);
+  mac_address[5] = static_cast<char>(raw_mac_addr >> 0);
+  SetMacAddress(mac_address);
+}
 
 BluetoothAdapter::~BluetoothAdapter() { SetStatus(Status::kDisabled); }
 
-void BluetoothAdapter::SetMedium(api::BluetoothClassicMedium* medium) {
-  medium_ = medium;
+void BluetoothAdapter::SetBluetoothClassicMedium(
+    api::BluetoothClassicMedium* medium) {
+  bluetooth_classic_medium_ = medium;
+}
+
+void BluetoothAdapter::SetBleMedium(api::BleMedium* medium) {
+  ble_medium_ = medium;
 }
 
 bool BluetoothAdapter::SetStatus(Status status) {

cpp/platform_v2/impl/g3/bluetooth_adapter.h

@@ -3,6 +3,7 @@
 
 #include <string>
 
+#include "platform_v2/api/ble.h"
 #include "platform_v2/api/bluetooth_adapter.h"
 #include "platform_v2/api/bluetooth_classic.h"
 #include "platform_v2/impl/g3/single_thread_executor.h"
@@ -17,6 +18,28 @@ namespace g3 {
 // BluetoothDevice and BluetoothAdapter have a mutual dependency.
 class BluetoothAdapter;
 
+// Opaque wrapper over a Ble peripheral. Must contain enough data about a
+// particular Ble device to connect to its GATT server.
+class BlePeripheral : public api::BlePeripheral {
+ public:
+  ~BlePeripheral() override = default;
+
+  std::string GetName() const override;
+  ByteArray GetAdvertisementBytes(const std::string& service_id) const override;
+  void SetAdvertisementBytes(const std::string& service_id,
+                             const ByteArray& advertisement_bytes);
+  BluetoothAdapter& GetAdapter() { return adapter_; }
+
+ private:
+  // Only BluetoothAdapter may instantiate BlePeripheral.
+  friend class BluetoothAdapter;
+
+  explicit BlePeripheral(BluetoothAdapter* adapter);
+
+  BluetoothAdapter& adapter_;
+  ByteArray advertisement_bytes_;
+};
+
 // https://developer.android.com/reference/android/bluetooth/BluetoothDevice.html.
 class BluetoothDevice : public api::BluetoothDevice {
  public:
@@ -24,6 +47,7 @@ class BluetoothDevice : public api::BluetoothDevice {
 
   // https://developer.android.com/reference/android/bluetooth/BluetoothDevice.html#getName()
   std::string GetName() const override;
+  std::string GetMacAddress() const override;
   BluetoothAdapter& GetAdapter() { return adapter_; }
 
  private:
@@ -41,7 +65,7 @@ class BluetoothAdapter : public api::BluetoothAdapter {
   using Status = api::BluetoothAdapter::Status;
   using ScanMode = api::BluetoothAdapter::ScanMode;
 
-  explicit BluetoothAdapter() = default;
+  BluetoothAdapter();
   ~BluetoothAdapter() override;
 
   // Synchronously sets the status of the BluetoothAdapter to 'status', and
@@ -68,15 +92,30 @@ class BluetoothAdapter : public api::BluetoothAdapter {
   // https://developer.android.com/reference/android/bluetooth/BluetoothAdapter.html#setName(java.lang.String)
   bool SetName(absl::string_view name) override ABSL_LOCKS_EXCLUDED(mutex_);
 
+  // Returns BT MAC address assigned to this adapter.
+  std::string GetMacAddress() const override { return mac_address_; }
+
   BluetoothDevice& GetDevice() { return device_; }
 
-  void SetMedium(api::BluetoothClassicMedium* medium);
-  api::BluetoothClassicMedium* GetMedium() { return medium_; }
+  void SetBluetoothClassicMedium(api::BluetoothClassicMedium* medium);
+  api::BluetoothClassicMedium* GetBluetoothClassicMedium() {
+    return bluetooth_classic_medium_;
+  }
+
+  BlePeripheral& GetPeripheral() { return peripheral_; }
+
+  void SetBleMedium(api::BleMedium* medium);
+  api::BleMedium* GetBleMedium() { return ble_medium_; }
+
+  void SetMacAddress(std::string& mac_address) { mac_address_ = mac_address; }
 
  private:
   mutable absl::Mutex mutex_;
   BluetoothDevice device_{this};
-  api::BluetoothClassicMedium* medium_ = nullptr;
+  BlePeripheral peripheral_{this};
+  api::BluetoothClassicMedium* bluetooth_classic_medium_ = nullptr;
+  api::BleMedium* ble_medium_ = nullptr;
+  std::string mac_address_;
   ScanMode mode_ ABSL_GUARDED_BY(mutex_) = ScanMode::kNone;
   std::string name_ ABSL_GUARDED_BY(mutex_) = "unknown G3 BT device";
   bool enabled_ ABSL_GUARDED_BY(mutex_) = false;

cpp/platform_v2/impl/g3/bluetooth_classic.cc

@@ -34,9 +34,7 @@ bool BluetoothSocket::IsClosed() const {
   return closed_;
 }
 
-bool BluetoothSocket::IsConnectedLocked() const {
-  return input_ != nullptr;
-}
+bool BluetoothSocket::IsConnectedLocked() const { return input_ != nullptr; }
 
 InputStream& BluetoothSocket::GetInputStream() {
   auto* remote_socket = GetRemoteSocket();
@@ -163,13 +161,13 @@ Exception BluetoothServerSocket::DoClose() {
 BluetoothClassicMedium::BluetoothClassicMedium(api::BluetoothAdapter& adapter)
     // TODO(apolyudov): implement and use downcast<> with static assertions.
     : adapter_(static_cast<BluetoothAdapter*>(&adapter)) {
-  adapter_->SetMedium(this);
+  adapter_->SetBluetoothClassicMedium(this);
   auto& env = MediumEnvironment::Instance();
   env.RegisterBluetoothMedium(*this, GetAdapter());
 }
 
 BluetoothClassicMedium::~BluetoothClassicMedium() {
-  adapter_->SetMedium(nullptr);
+  adapter_->SetBluetoothClassicMedium(nullptr);
   auto& env = MediumEnvironment::Instance();
   env.UnregisterBluetoothMedium(*this);
 }
@@ -193,7 +191,8 @@ std::unique_ptr<api::BluetoothSocket> BluetoothClassicMedium::ConnectToService(
              this, &GetAdapter(), &GetAdapter().GetDevice());
   // First, find an instance of remote medium, that exposed this device.
   auto& adapter = static_cast<BluetoothDevice&>(remote_device).GetAdapter();
-  auto* medium = static_cast<BluetoothClassicMedium*>(adapter.GetMedium());
+  auto* medium =
+      static_cast<BluetoothClassicMedium*>(adapter.GetBluetoothClassicMedium());
 
   if (!medium) return {};  // Adapter is not bound to medium. Bail out.
 
@@ -241,6 +240,12 @@ BluetoothClassicMedium::ListenForService(const std::string& service_name,
   return socket;
 }
 
+api::BluetoothDevice* BluetoothClassicMedium::FindRemoteDevice(
+    const std::string& mac_address) {
+  auto& env = MediumEnvironment::Instance();
+  return env.FindBluetoothDevice(mac_address);
+}
+
 }  // namespace g3
 }  // namespace nearby
 }  // namespace location

cpp/platform_v2/impl/g3/bluetooth_classic.h

@@ -82,7 +82,7 @@ class BluetoothSocket : public api::BluetoothSocket {
   // Output pipe is initialized by constructor, it remains always valid, until
   // it is closed. it represents output part of a local socket. Input part of a
   // local socket comes from the peer socket, after connection.
-  std::shared_ptr<Pipe> output_ {new Pipe};
+  std::shared_ptr<Pipe> output_{new Pipe};
   std::shared_ptr<Pipe> input_;
   mutable absl::Mutex mutex_;
   BluetoothAdapter* adapter_ = nullptr;  // Our Adapter. Read only.
@@ -207,6 +207,9 @@ class BluetoothClassicMedium : public api::BluetoothClassicMedium {
       const std::string& service_name, const std::string& service_uuid) override
       ABSL_LOCKS_EXCLUDED(mutex_);
 
+  api::BluetoothDevice* FindRemoteDevice(
+      const std::string& mac_address) override;
+
  private:
   absl::Mutex mutex_;
   BluetoothAdapter* adapter_;  // Our device adapter; read-only.

cpp/platform_v2/impl/g3/platform.cc

@@ -5,7 +5,6 @@
 
 #include "platform_v2/api/atomic_boolean.h"
 #include "platform_v2/api/atomic_reference.h"
-#include "platform_v2/api/ble.h"
 #include "platform_v2/api/ble_v2.h"
 #include "platform_v2/api/bluetooth_adapter.h"
 #include "platform_v2/api/bluetooth_classic.h"
@@ -21,6 +20,7 @@
 #include "platform_v2/base/medium_environment.h"
 #include "platform_v2/impl/g3/atomic_boolean.h"
 #include "platform_v2/impl/g3/atomic_reference.h"
+#include "platform_v2/impl/g3/ble.h"
 #include "platform_v2/impl/g3/bluetooth_adapter.h"
 #include "platform_v2/impl/g3/bluetooth_classic.h"
 #include "platform_v2/impl/g3/condition_variable.h"
@@ -112,7 +112,7 @@ ImplementationPlatform::CreateBluetoothClassicMedium(
 
 std::unique_ptr<BleMedium> ImplementationPlatform::CreateBleMedium(
     api::BluetoothAdapter& adapter) {
-  return std::unique_ptr<BleMedium>();
+  return absl::make_unique<g3::BleMedium>(adapter);
 }
 
 std::unique_ptr<ble_v2::BleMedium> ImplementationPlatform::CreateBleV2Medium(

cpp/platform_v2/impl/g3/wifi_lan.cc

@@ -7,6 +7,7 @@
 #include "platform_v2/api/wifi_lan.h"
 #include "platform_v2/base/logging.h"
 #include "platform_v2/base/medium_environment.h"
+#include "platform_v2/base/prng.h"
 #include "absl/synchronization/mutex.h"
 
 namespace location {
@@ -85,7 +86,8 @@ OutputStream& WifiLanSocket::GetLocalOutputStream() {
   return output_->GetOutputStream();
 }
 
-std::unique_ptr<api::WifiLanSocket> WifiLanServerSocket::Accept() {
+std::unique_ptr<api::WifiLanSocket> WifiLanServerSocket::Accept(
+    WifiLanService* service) {
   absl::MutexLock lock(&mutex_);
   if (closed_) return {};
   while (pending_sockets_.empty()) {
@@ -96,7 +98,7 @@ std::unique_ptr<api::WifiLanSocket> WifiLanServerSocket::Accept() {
   auto* remote_socket =
       pending_sockets_.extract(pending_sockets_.begin()).value();
   CHECK(remote_socket);
-  auto local_socket = std::make_unique<WifiLanSocket>();
+  auto local_socket = std::make_unique<WifiLanSocket>(service);
   local_socket->Connect(*remote_socket);
   remote_socket->Connect(*local_socket);
   cond_.SignalAll();
@@ -155,6 +157,15 @@ Exception WifiLanServerSocket::DoClose() {
 
 WifiLanMedium::WifiLanMedium() {
   service_.SetMedium(this);
+  std::string ip_address;
+  ip_address.resize(4);
+  uint32_t raw_ip_addr = Prng().NextUint32();
+  uint16_t port = Prng().NextUint32();
+  ip_address[0] = static_cast<char>(raw_ip_addr >> 24);
+  ip_address[1] = static_cast<char>(raw_ip_addr >> 16);
+  ip_address[2] = static_cast<char>(raw_ip_addr >> 8);
+  ip_address[3] = static_cast<char>(raw_ip_addr >> 0);
+  service_.SetServiceAddress(ip_address, port);
   auto& env = MediumEnvironment::Instance();
   env.RegisterWifiLanMedium(*this);
 }
@@ -167,8 +178,7 @@ WifiLanMedium::~WifiLanMedium() {
   StopAdvertising(advertising_info_.service_id);
   StopDiscovery(discovering_info_.service_id);
 
-  NEARBY_LOG(INFO,
-             "WifiLanMedium dtor advertising_accept_thread_running_ = %d",
+  NEARBY_LOG(INFO, "WifiLanMedium dtor advertising_accept_thread_running_ = %d",
              acceptance_thread_running_.load());
   // If acceptance thread is still running, wait to finish.
   if (acceptance_thread_running_) {
@@ -186,6 +196,7 @@ bool WifiLanMedium::StartAdvertising(const std::string& service_id,
              "G3 WifiLan StartAdvertising: service_id=%s, service_info_name=%s",
              service_id.c_str(), service_info_name.c_str());
   auto& env = MediumEnvironment::Instance();
+  service_.SetName(service_info_name);
   env.UpdateWifiLanMediumForAdvertising(*this, service_, service_id, true);
 
   absl::MutexLock lock(&mutex_);
@@ -196,10 +207,10 @@ bool WifiLanMedium::StartAdvertising(const std::string& service_id,
   accept_loops_runner_.Execute([&env, this, service_id]() mutable {
     if (!accept_loops_runner_.InShutdown()) {
       while (true) {
-        auto client_socket = server_socket_->Accept();
+        auto client_socket = server_socket_->Accept(&service_);
         if (client_socket == nullptr) break;
-        env.CallWifiLanAcceptedConnectionCallback(*this, *client_socket,
-                                                  service_id);
+        env.CallWifiLanAcceptedConnectionCallback(
+            *this, *(client_socket.release()), service_id);
       }
     }
     acceptance_thread_running_.exchange(false);
@@ -227,8 +238,8 @@ bool WifiLanMedium::StopAdvertising(const std::string& service_id) {
   accept_loops_runner_.Shutdown();
   if (server_socket_ == nullptr) {
     NEARBY_LOGS(ERROR) << "G3 WifiLan StopAdvertising: failed to find WifiLan "
-                         "Server socket: service_id="
-                      << service_id;
+                          "Server socket: service_id="
+                       << service_id;
     // Fall through for server socket not found.
     return true;
   }
@@ -296,8 +307,11 @@ bool WifiLanMedium::StopAcceptingConnections(const std::string& service_id) {
 
 std::unique_ptr<api::WifiLanSocket> WifiLanMedium::Connect(
     api::WifiLanService& remote_service, const std::string& service_id) {
-  NEARBY_LOG(INFO, "G3 WifiLan Connect: medium=%p, service=%p, service_id=%s",
-             this, &service_, service_id.c_str());
+  NEARBY_LOG(INFO,
+             "G3 WifiLan Connect: medium=%p, service=%p, service_info_name=%s, "
+             "service_id=%s",
+             this, &service_, remote_service.GetName().c_str(),
+             service_id.c_str());
   // First, find an instance of remote medium, that exposed this service.
   auto* medium = static_cast<WifiLanService&>(remote_service).GetMedium();
 
@@ -305,8 +319,10 @@ std::unique_ptr<api::WifiLanSocket> WifiLanMedium::Connect(
 
   WifiLanServerSocket* remote_server_socket = nullptr;
   NEARBY_LOG(INFO,
-             "G3 WifiLan Connect [peer]: medium=%p, service=%p, service_id=%s",
-             medium, &remote_service, service_id.c_str());
+             "G3 WifiLan Connect [peer]: medium=%p, service=%p, "
+             "service_info_name=%s, service_id=%s",
+             medium, &remote_service, remote_service.GetName().c_str(),
+             service_id.c_str());
   // Then, find our server socket context in this medium.
   {
     absl::MutexLock medium_lock(&medium->mutex_);
@@ -321,7 +337,8 @@ std::unique_ptr<api::WifiLanSocket> WifiLanMedium::Connect(
     }
   }
 
-  auto socket = std::make_unique<WifiLanSocket>();
+  WifiLanService service = static_cast<WifiLanService&>(remote_service);
+  auto socket = std::make_unique<WifiLanSocket>(&service);
   // Finally, Request to connect to this socket.
   if (!remote_server_socket->Connect(*socket)) {
     NEARBY_LOG(ERROR,
@@ -335,6 +352,12 @@ std::unique_ptr<api::WifiLanSocket> WifiLanMedium::Connect(
   return socket;
 }
 
+api::WifiLanService* WifiLanMedium::FindRemoteService(
+    const std::string& ip_address, int port) {
+  auto& env = MediumEnvironment::Instance();
+  return env.FindWifiLanService(ip_address, port);
+}
+
 }  // namespace g3
 }  // namespace nearby
 }  // namespace location

cpp/platform_v2/impl/g3/wifi_lan.h

@@ -3,6 +3,7 @@
 
 #include <memory>
 #include <string>
+#include <utility>
 
 #include "platform_v2/api/wifi_lan.h"
 #include "platform_v2/base/byte_array.h"
@@ -32,13 +33,23 @@ class WifiLanService : public api::WifiLanService {
     service_info_name_ = std::move(service_info_name);
   }
   std::string GetName() const override { return service_info_name_; }
+  std::pair<std::string, int> GetServiceAddress() const override {
+    return std::make_pair(ip_address_, port_);
+  }
 
   void SetMedium(WifiLanMedium* medium) { medium_ = medium; }
   WifiLanMedium* GetMedium() { return medium_; }
 
+  void SetServiceAddress(const std::string& ip_address, int port) {
+    ip_address_ = ip_address;
+    port_ = port;
+  }
+
  private:
   std::string service_info_name_;
   WifiLanMedium* medium_ = nullptr;
+  std::string ip_address_;
+  int port_;
 };
 
 class WifiLanSocket : public api::WifiLanSocket {
@@ -94,7 +105,7 @@ class WifiLanSocket : public api::WifiLanSocket {
   // Output pipe is initialized by constructor, it remains always valid, until
   // it is closed. it represents output part of a local socket. Input part of a
   // local socket comes from the peer socket, after connection.
-  std::shared_ptr<Pipe> output_ {new Pipe};
+  std::shared_ptr<Pipe> output_{new Pipe};
   std::shared_ptr<Pipe> input_;
   mutable absl::Mutex mutex_;
   WifiLanService* service_;
@@ -116,7 +127,8 @@ class WifiLanServerSocket {
   // Called by the server side of a connection.
   // Returns WifiLanSocket to the server side.
   // If not null, returned socket is connected to its remote (client-side) peer.
-  std::unique_ptr<api::WifiLanSocket> Accept() ABSL_LOCKS_EXCLUDED(mutex_);
+  std::unique_ptr<api::WifiLanSocket> Accept(WifiLanService* service)
+      ABSL_LOCKS_EXCLUDED(mutex_);
 
   // Blocks until either:
   // - connection is available, or
@@ -186,6 +198,9 @@ class WifiLanMedium : public api::WifiLanMedium {
       api::WifiLanService& remote_service,
       const std::string& service_id) override ABSL_LOCKS_EXCLUDED(mutex_);
 
+  api::WifiLanService* FindRemoteService(const std::string& ip_address,
+                                         int port) override;
+
  private:
   static constexpr int kMaxConcurrentAcceptLoops = 5;
 

cpp/platform_v2/impl/shared/BUILD

@@ -20,9 +20,7 @@ cc_library(
     hdrs = [
         "posix_condition_variable.h",
     ],
-    visibility = [
-        "//platform_v2/impl:__subpackages__",
-    ],
+    visibility = ["//visibility:private"],
     deps = [
         ":posix_mutex",
         "//platform_v2/api:types",