MacOS implementation of BluetoothSocket.

BUG=343725,343651

Review URL: https://codereview.chromium.org/229463003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@263018 0039d316-1c4b-4281-b951-d872f2087c98

7 files changed, 527 insertions, 149 deletions

diff --git a/device/bluetooth/bluetooth_adapter_mac.mm b/device/bluetooth/bluetooth_adapter_mac.mm
index 9ac7caa..f8eba23 100644
--- a/device/bluetooth/bluetooth_adapter_mac.mm
+++ b/device/bluetooth/bluetooth_adapter_mac.mm
@@ -265,7 +265,7 @@ void BluetoothAdapterMac::UpdateDevices(NSArray* devices) {
   for (IOBluetoothDevice* device in devices) {
     std::string device_address =
         base::SysNSStringToUTF8([device addressString]);
-    devices_[device_address] = new BluetoothDeviceMac(device);
+    devices_[device_address] = new BluetoothDeviceMac(ui_task_runner_, device);
   }
 }
 
@@ -290,7 +290,8 @@ void BluetoothAdapterMac::DeviceFound(IOBluetoothDeviceInquiry* inquiry,
   DCHECK(device_inquiry_ == inquiry);
   std::string device_address = base::SysNSStringToUTF8([device addressString]);
   if (discovered_devices_.find(device_address) == discovered_devices_.end()) {
-    scoped_ptr<BluetoothDeviceMac> device_mac(new BluetoothDeviceMac(device));
+    scoped_ptr<BluetoothDeviceMac> device_mac(
+        new BluetoothDeviceMac(ui_task_runner_, device));
     FOR_EACH_OBSERVER(BluetoothAdapter::Observer, observers_,
                       DeviceAdded(this, device_mac.get()));
     discovered_devices_.insert(device_address);
diff --git a/device/bluetooth/bluetooth_device_mac.h b/device/bluetooth/bluetooth_device_mac.h
index e0ed024..e7bec55 100644
--- a/device/bluetooth/bluetooth_device_mac.h
+++ b/device/bluetooth/bluetooth_device_mac.h
@@ -17,11 +17,17 @@
 class IOBluetoothDevice;
 #endif
 
+namespace base {
+class SequencedTaskRunner;
+}  // namespace base
+
 namespace device {
 
 class BluetoothDeviceMac : public BluetoothDevice {
  public:
-  explicit BluetoothDeviceMac(IOBluetoothDevice* device);
+  explicit BluetoothDeviceMac(
+      const scoped_refptr<base::SequencedTaskRunner>& ui_task_runner,
+      IOBluetoothDevice* device);
   virtual ~BluetoothDeviceMac();
 
   // BluetoothDevice override
@@ -81,6 +87,8 @@ class BluetoothDeviceMac : public BluetoothDevice {
   // List of observers interested in event notifications from us.
   ObserverList<Observer> observers_;
 
+  scoped_refptr<base::SequencedTaskRunner> ui_task_runner_;
+  // (retained)
   IOBluetoothDevice* device_;
 
   DISALLOW_COPY_AND_ASSIGN(BluetoothDeviceMac);
diff --git a/device/bluetooth/bluetooth_device_mac.mm b/device/bluetooth/bluetooth_device_mac.mm
index bd25449..bd54495 100644
--- a/device/bluetooth/bluetooth_device_mac.mm
+++ b/device/bluetooth/bluetooth_device_mac.mm
@@ -13,6 +13,7 @@
 
 #include "base/basictypes.h"
 #include "base/hash.h"
+#include "base/sequenced_task_runner.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/sys_string_conversions.h"
@@ -36,8 +37,6 @@
 
 namespace {
 
-const char kFailedToConnect[] = "Connection failed";
-
 // Converts |uuid| to a IOBluetoothSDPUUID instance.
 //
 // |uuid| must be in the format of XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX.
@@ -64,9 +63,12 @@ IOBluetoothSDPUUID* GetIOBluetoothSDPUUID(const std::string& uuid) {
 
 namespace device {
 
-BluetoothDeviceMac::BluetoothDeviceMac(IOBluetoothDevice* device)
-    : BluetoothDevice(), device_([device retain]) {
-}
+BluetoothDeviceMac::BluetoothDeviceMac(
+    const scoped_refptr<base::SequencedTaskRunner>& ui_task_runner,
+    IOBluetoothDevice* device)
+    : BluetoothDevice(),
+      ui_task_runner_(ui_task_runner),
+      device_([device retain]) {}
 
 BluetoothDeviceMac::~BluetoothDeviceMac() {
   [device_ release];
@@ -199,9 +201,8 @@ void BluetoothDeviceMac::ConnectToService(
       [device_ getServiceRecordForUUID:GetIOBluetoothSDPUUID(
           service_uuid.canonical_value())];
   if (record != nil) {
-    BluetoothServiceRecordMac service_record(record);
     scoped_refptr<BluetoothSocket> socket(
-        BluetoothSocketMac::CreateBluetoothSocket(service_record));
+        BluetoothSocketMac::CreateBluetoothSocket(ui_task_runner_, record));
     if (socket.get() != NULL)
       callback.Run(socket);
   }
@@ -211,10 +212,9 @@ void BluetoothDeviceMac::ConnectToProfile(
     BluetoothProfile* profile,
     const base::Closure& callback,
     const ConnectToProfileErrorCallback& error_callback) {
-  if (static_cast<BluetoothProfileMac*>(profile)->Connect(device_))
-    callback.Run();
-  else
-    error_callback.Run(kFailedToConnect);
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
+  static_cast<BluetoothProfileMac*>(profile)
+      ->Connect(ui_task_runner_, device_, callback, error_callback);
 }
 
 void BluetoothDeviceMac::SetOutOfBandPairingData(
diff --git a/device/bluetooth/bluetooth_profile_mac.h b/device/bluetooth/bluetooth_profile_mac.h
index bad10ce..673abeb 100644
--- a/device/bluetooth/bluetooth_profile_mac.h
+++ b/device/bluetooth/bluetooth_profile_mac.h
@@ -18,6 +18,10 @@
 class IOBluetoothDevice;
 #endif
 
+namespace base {
+class SequencedTaskRunner;
+}  // namespace base
+
 namespace device {
 
 class BluetoothProfileMac : public BluetoothProfile {
@@ -27,10 +31,15 @@ class BluetoothProfileMac : public BluetoothProfile {
   virtual void SetConnectionCallback(
       const ConnectionCallback& callback) OVERRIDE;
 
-  // Makes an outgoing connection to |device|.
-  // This method runs |socket_callback_| with the socket and returns true if the
-  // connection is made successfully.
-  bool Connect(IOBluetoothDevice* device);
+  typedef base::Callback<void(const std::string&)> ErrorCallback;
+
+  // Makes an outgoing connection to |device|, calling |callback| on succes or
+  // |error_callback| on error. If successful, this method also calls
+  // |connection_callback_| before calling |callback|.
+  void Connect(const scoped_refptr<base::SequencedTaskRunner>& ui_task_runner,
+               IOBluetoothDevice* device,
+               const base::Closure& callback,
+               const ErrorCallback& error_callback);
 
  private:
   friend BluetoothProfile;
diff --git a/device/bluetooth/bluetooth_profile_mac.mm b/device/bluetooth/bluetooth_profile_mac.mm
index 54781e4..b666877 100644
--- a/device/bluetooth/bluetooth_profile_mac.mm
+++ b/device/bluetooth/bluetooth_profile_mac.mm
@@ -12,14 +12,32 @@
 #include <vector>
 
 #include "base/basictypes.h"
+#include "base/bind.h"
+#include "base/location.h"
 #include "base/logging.h"
 #include "base/memory/ref_counted.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/strings/sys_string_conversions.h"
+#include "base/thread_task_runner_handle.h"
+#include "device/bluetooth/bluetooth_adapter_factory.h"
 #include "device/bluetooth/bluetooth_device_mac.h"
 #include "device/bluetooth/bluetooth_socket_mac.h"
 
+// Replicate specific 10.7 SDK declarations for building with prior SDKs.
+#if !defined(MAC_OS_X_VERSION_10_7) || \
+    MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_7
+
+@interface IOBluetoothDevice (LionSDKDeclarations)
+- (NSString*)addressString;
+@end
+
+#endif  // MAC_OS_X_VERSION_10_7
+
 namespace {
 
+const char kNoConnectionCallback[] = "Connection callback not set";
+const char kProfileNotFound[] = "Profile not found";
+
 // Converts |uuid| to a IOBluetoothSDPUUID instance.
 //
 // |uuid| must be in the format of XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX.
@@ -42,6 +60,54 @@ IOBluetoothSDPUUID* GetIOBluetoothSDPUUID(const std::string& uuid) {
                                     length:uuid_bytes_vector.size()];
 }
 
+void OnSocketConnectUI(
+    scoped_refptr<base::SequencedTaskRunner> ui_task_runner,
+    scoped_refptr<device::BluetoothSocketMac> socket,
+    const base::Closure& success_callback,
+    const device::BluetoothProfileMac::ErrorCallback& error_callback) {
+  DCHECK(ui_task_runner->RunsTasksOnCurrentThread());
+  socket->Connect(success_callback, error_callback);
+}
+
+void OnConnectSuccessUIWithAdapter(
+    scoped_refptr<base::SequencedTaskRunner> ui_task_runner,
+    const base::Closure& callback,
+    const device::BluetoothProfileMac::ConnectionCallback& connection_callback,
+    const std::string& device_address,
+    scoped_refptr<device::BluetoothSocketMac> socket,
+    scoped_refptr<device::BluetoothAdapter> adapter) {
+  DCHECK(ui_task_runner->RunsTasksOnCurrentThread());
+  const device::BluetoothDevice* device = adapter->GetDevice(device_address);
+  if (device) {
+    connection_callback.Run(device, socket);
+    callback.Run();
+  }
+}
+
+void OnConnectSuccessUI(
+    scoped_refptr<base::SequencedTaskRunner> ui_task_runner,
+    const base::Closure& callback,
+    const device::BluetoothProfileMac::ConnectionCallback& connection_callback,
+    const std::string& device_address,
+    scoped_refptr<device::BluetoothSocketMac> socket) {
+  DCHECK(ui_task_runner->RunsTasksOnCurrentThread());
+  device::BluetoothAdapterFactory::GetAdapter(
+      base::Bind(&OnConnectSuccessUIWithAdapter,
+                 ui_task_runner,
+                 callback,
+                 connection_callback,
+                 device_address,
+                 socket));
+}
+
+void OnConnectErrorUI(
+    scoped_refptr<base::SequencedTaskRunner> ui_task_runner,
+    const device::BluetoothProfileMac::ErrorCallback& error_callback,
+    const std::string& error) {
+  DCHECK(ui_task_runner->RunsTasksOnCurrentThread());
+  error_callback.Run(error);
+}
+
 }  // namespace
 
 namespace device {
@@ -63,23 +129,37 @@ void BluetoothProfileMac::SetConnectionCallback(
   connection_callback_ = callback;
 }
 
-bool BluetoothProfileMac::Connect(IOBluetoothDevice* device) {
-  if (connection_callback_.is_null())
-    return false;
-
-  IOBluetoothSDPServiceRecord* record =
-      [device getServiceRecordForUUID:GetIOBluetoothSDPUUID(
-          uuid_.canonical_value())];
-  if (record != nil) {
-    scoped_refptr<BluetoothSocket> socket(
-        BluetoothSocketMac::CreateBluetoothSocket(record));
-    if (socket.get() != NULL) {
-      BluetoothDeviceMac device_mac(device);
-      connection_callback_.Run(&device_mac, socket);
-      return true;
-    }
+void BluetoothProfileMac::Connect(
+    const scoped_refptr<base::SequencedTaskRunner>& ui_task_runner,
+    IOBluetoothDevice* device,
+    const base::Closure& success_callback,
+    const ErrorCallback& error_callback) {
+  DCHECK(ui_task_runner->RunsTasksOnCurrentThread());
+  if (connection_callback_.is_null()) {
+    error_callback.Run(kNoConnectionCallback);
+    return;
+  }
+
+  IOBluetoothSDPServiceRecord* record = [device
+      getServiceRecordForUUID:GetIOBluetoothSDPUUID(uuid_.canonical_value())];
+  if (record == nil) {
+    error_callback.Run(kProfileNotFound);
+    return;
   }
-  return false;
+
+  std::string device_address = base::SysNSStringToUTF8([device addressString]);
+  scoped_refptr<BluetoothSocketMac> socket(
+      BluetoothSocketMac::CreateBluetoothSocket(ui_task_runner, record));
+  OnSocketConnectUI(
+      ui_task_runner,
+      socket,
+      base::Bind(OnConnectSuccessUI,
+                 ui_task_runner,
+                 success_callback,
+                 connection_callback_,
+                 device_address,
+                 socket),
+      base::Bind(OnConnectErrorUI, ui_task_runner, error_callback));
 }
 
 }  // namespace device
diff --git a/device/bluetooth/bluetooth_socket_mac.h b/device/bluetooth/bluetooth_socket_mac.h
index 806eceb..76e197d 100644
--- a/device/bluetooth/bluetooth_socket_mac.h
+++ b/device/bluetooth/bluetooth_socket_mac.h
@@ -5,9 +5,15 @@
 #ifndef DEVICE_BLUETOOTH_BLUETOOTH_SOCKET_MAC_H_
 #define DEVICE_BLUETOOTH_BLUETOOTH_SOCKET_MAC_H_
 
+#include <queue>
 #include <string>
 
+#include <IOKit/IOreturn.h>
+
+#include "base/memory/linked_ptr.h"
 #include "base/memory/ref_counted.h"
+#include "base/sequenced_task_runner.h"
+#include "base/threading/thread_checker.h"
 #include "device/bluetooth/bluetooth_socket.h"
 
 #ifdef __OBJC__
@@ -21,8 +27,8 @@ class IOBluetoothSDPServiceRecord;
 #endif
 
 namespace net {
-class GrowableIOBuffer;
 class IOBuffer;
+class IOBufferWithSize;
 }  // namespace net
 
 namespace device {
@@ -30,16 +36,20 @@ namespace device {
 class BluetoothServiceRecord;
 
 // This class is an implementation of BluetoothSocket class for OSX platform.
+// All methods of this class must all be called on the UI thread, as per Chrome
+// guidelines on performing Async IO on UI thread on MacOS.
 class BluetoothSocketMac : public BluetoothSocket {
  public:
-  // TODO(youngki): This method is deprecated; remove this method when
-  // BluetoothServiceRecord is removed.
-  static scoped_refptr<BluetoothSocket> CreateBluetoothSocket(
-      const BluetoothServiceRecord& service_record);
-
-  static scoped_refptr<BluetoothSocket> CreateBluetoothSocket(
+  static scoped_refptr<BluetoothSocketMac> CreateBluetoothSocket(
+      const scoped_refptr<base::SequencedTaskRunner>& ui_task_runner,
       IOBluetoothSDPServiceRecord* record);
 
+  // Connect to the peer device and calls |success_callback| when the
+  // connection has been established successfully. If an error occurs, calls
+  // |error_callback| with a system error message.
+  void Connect(const base::Closure& success_callback,
+               const ErrorCompletionCallback& error_callback);
+
   // Overriden from BluetoothSocket:
   virtual void Close() OVERRIDE;
   virtual void Disconnect(const base::Closure& callback) OVERRIDE;
@@ -53,22 +63,77 @@ class BluetoothSocketMac : public BluetoothSocket {
                     const ErrorCompletionCallback& error_callback) OVERRIDE;
 
   // called by BluetoothRFCOMMChannelDelegate.
-  void OnDataReceived(IOBluetoothRFCOMMChannel* rfcomm_channel,
-                      void* data,
-                      size_t length);
+  void OnChannelOpened(IOBluetoothRFCOMMChannel* rfcomm_channel,
+                       IOReturn status);
+
+  // called by BluetoothRFCOMMChannelDelegate.
+  void OnChannelClosed(IOBluetoothRFCOMMChannel* rfcomm_channel);
+
+  // called by BluetoothRFCOMMChannelDelegate.
+  void OnChannelDataReceived(IOBluetoothRFCOMMChannel* rfcomm_channel,
+                             void* data,
+                             size_t length);
+
+  // called by BluetoothRFCOMMChannelDelegate.
+  void OnChannelWriteComplete(IOBluetoothRFCOMMChannel* rfcomm_channel,
+                              void* refcon,
+                              IOReturn status);
 
  protected:
   virtual ~BluetoothSocketMac();
 
  private:
-  explicit BluetoothSocketMac(IOBluetoothRFCOMMChannel* rfcomm_channel);
-
-  void ResetIncomingDataBuffer();
+  BluetoothSocketMac(
+      const scoped_refptr<base::SequencedTaskRunner>& ui_task_runner,
+      IOBluetoothSDPServiceRecord* record);
 
-  IOBluetoothRFCOMMChannel* rfcomm_channel_;
+  struct SendRequest {
+    SendRequest();
+    ~SendRequest();
+    int buffer_size;
+    SendCompletionCallback success_callback;
+    ErrorCompletionCallback error_callback;
+    IOReturn status;
+    int active_async_writes;
+    bool error_signaled;
+  };
+
+  struct ReceiveCallbacks {
+    ReceiveCallbacks();
+    ~ReceiveCallbacks();
+    ReceiveCompletionCallback success_callback;
+    ReceiveErrorCompletionCallback error_callback;
+  };
+
+  struct ConnectCallbacks {
+    ConnectCallbacks();
+    ~ConnectCallbacks();
+    base::Closure success_callback;
+    ErrorCompletionCallback error_callback;
+  };
+
+  void ReleaseChannel();
+
+  bool connecting() const { return connect_callbacks_; }
+
+  // Used to verify all methods are called on the same thread.
+  base::ThreadChecker thread_checker_;
+  // Task Runner for the UI thread, used to post tasks.
+  scoped_refptr<base::SequencedTaskRunner> ui_task_runner_;
+  // (retained) The Bluetooth Service definition.
+  IOBluetoothSDPServiceRecord* record_;
+  // (weak) The RFCOMM channel delegate. Released when the channel is closed.
   BluetoothRFCOMMChannelDelegate* delegate_;
-  scoped_refptr<net::GrowableIOBuffer> incoming_data_buffer_;
-  std::string error_message_;
+  // (retained) The IOBluetooth RFCOMM channel used to issue commands.
+  IOBluetoothRFCOMMChannel* rfcomm_channel_;
+  // Connection callbacks -- when a pending async connection is active.
+  scoped_ptr<ConnectCallbacks> connect_callbacks_;
+  // Packets received while there is no pending "receive" callback.
+  std::queue<scoped_refptr<net::IOBufferWithSize> > receive_queue_;
+  // Receive callbacks -- when a receive call is active.
+  scoped_ptr<ReceiveCallbacks> receive_callbacks_;
+  // Send queue -- one entry per pending send operation.
+  std::queue<linked_ptr<SendRequest> > send_queue_;
 
   DISALLOW_COPY_AND_ASSIGN(BluetoothSocketMac);
 };
diff --git a/device/bluetooth/bluetooth_socket_mac.mm b/device/bluetooth/bluetooth_socket_mac.mm
index b4a88c0..cee05a5 100644
--- a/device/bluetooth/bluetooth_socket_mac.mm
+++ b/device/bluetooth/bluetooth_socket_mac.mm
@@ -9,12 +9,15 @@
 #import <IOBluetooth/objc/IOBluetoothSDPServiceRecord.h>
 
 #include <limits>
+#include <sstream>
 #include <string>
 
 #include "base/basictypes.h"
+#include "base/callback_helpers.h"
 #include "base/memory/ref_counted.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/sys_string_conversions.h"
+#include "base/threading/thread_restrictions.h"
 #include "device/bluetooth/bluetooth_service_record.h"
 #include "device/bluetooth/bluetooth_service_record_mac.h"
 #include "net/base/io_buffer.h"
@@ -48,156 +51,368 @@
   return self;
 }
 
+- (void)rfcommChannelOpenComplete:(IOBluetoothRFCOMMChannel*)rfcommChannel
+                           status:(IOReturn)error {
+  socket_->OnChannelOpened(rfcommChannel, error);
+}
+
+- (void)rfcommChannelWriteComplete:(IOBluetoothRFCOMMChannel*)rfcommChannel
+                            refcon:(void*)refcon
+                            status:(IOReturn)error {
+  socket_->OnChannelWriteComplete(rfcommChannel, refcon, error);
+}
+
 - (void)rfcommChannelData:(IOBluetoothRFCOMMChannel*)rfcommChannel
                      data:(void*)dataPointer
                    length:(size_t)dataLength {
-  socket_->OnDataReceived(rfcommChannel, dataPointer, dataLength);
+  socket_->OnChannelDataReceived(rfcommChannel, dataPointer, dataLength);
+}
+
+- (void)rfcommChannelClosed:(IOBluetoothRFCOMMChannel*)rfcommChannel {
+  socket_->OnChannelClosed(rfcommChannel);
 }
 
 @end
 
+namespace {
+
+const char kL2CAPNotSupported[] = "Bluetooth L2CAP protocol is not supported";
+const char kSocketConnecting[] = "The socket is currently connecting";
+const char kSocketAlreadyConnected[] = "The socket is already connected";
+const char kSocketNotConnected[] = "The socket is not connected";
+const char kReceivePending[] = "A Receive operation is pending";
+
+template <class T>
+void empty_queue(std::queue<T>& queue) {
+  std::queue<T> empty;
+  std::swap(queue, empty);
+}
+
+}  // namespace
+
 namespace device {
 
-BluetoothSocketMac::BluetoothSocketMac(IOBluetoothRFCOMMChannel* rfcomm_channel)
-    : rfcomm_channel_(rfcomm_channel),
-      delegate_([[BluetoothRFCOMMChannelDelegate alloc] initWithSocket:this]) {
-  [rfcomm_channel_ setDelegate:delegate_];
-  ResetIncomingDataBuffer();
+BluetoothSocketMac::SendRequest::SendRequest()
+    : status(kIOReturnSuccess), active_async_writes(0), error_signaled(false) {}
+
+BluetoothSocketMac::SendRequest::~SendRequest() {}
+
+BluetoothSocketMac::ReceiveCallbacks::ReceiveCallbacks() {}
+
+BluetoothSocketMac::ReceiveCallbacks::~ReceiveCallbacks() {}
+
+BluetoothSocketMac::ConnectCallbacks::ConnectCallbacks() {}
+
+BluetoothSocketMac::ConnectCallbacks::~ConnectCallbacks() {}
+
+// static
+scoped_refptr<BluetoothSocketMac> BluetoothSocketMac::CreateBluetoothSocket(
+    const scoped_refptr<base::SequencedTaskRunner>& ui_task_runner,
+    IOBluetoothSDPServiceRecord* record) {
+  return new BluetoothSocketMac(ui_task_runner, record);
+}
+
+BluetoothSocketMac::BluetoothSocketMac(
+    const scoped_refptr<base::SequencedTaskRunner>& ui_task_runner,
+    IOBluetoothSDPServiceRecord* record)
+    : ui_task_runner_(ui_task_runner),
+      record_(record),
+      delegate_([[BluetoothRFCOMMChannelDelegate alloc] initWithSocket:this]),
+      rfcomm_channel_(nil) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
+  [record_ retain];
 }
 
 BluetoothSocketMac::~BluetoothSocketMac() {
-  [rfcomm_channel_ setDelegate:nil];
-  [rfcomm_channel_ closeChannel];
-  [rfcomm_channel_ release];
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
+  ReleaseChannel();
   [delegate_ release];
+  [record_ release];
 }
 
-// static
-scoped_refptr<BluetoothSocket> BluetoothSocketMac::CreateBluetoothSocket(
-    const BluetoothServiceRecord& service_record) {
-  BluetoothSocketMac* bluetooth_socket = NULL;
-  if (service_record.SupportsRfcomm()) {
-    const BluetoothServiceRecordMac* service_record_mac =
-        static_cast<const BluetoothServiceRecordMac*>(&service_record);
-    IOBluetoothDevice* device = service_record_mac->GetIOBluetoothDevice();
-    IOBluetoothRFCOMMChannel* rfcomm_channel;
-    IOReturn status =
-        [device openRFCOMMChannelAsync:&rfcomm_channel
-                         withChannelID:service_record.rfcomm_channel()
-                              delegate:nil];
-    if (status == kIOReturnSuccess) {
-      bluetooth_socket = new BluetoothSocketMac(rfcomm_channel);
-    } else {
-      LOG(ERROR) << "Failed to connect bluetooth socket ("
-          << service_record.address() << "): (" << status << ")";
-    }
+void BluetoothSocketMac::ReleaseChannel() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
+  if (rfcomm_channel_ != nil) {
+    [rfcomm_channel_ setDelegate:nil];
+    [rfcomm_channel_ closeChannel];
+    [rfcomm_channel_ release];
+    rfcomm_channel_ = nil;
   }
-  // TODO(youngki): add support for L2CAP sockets as well.
 
-  return scoped_refptr<BluetoothSocketMac>(bluetooth_socket);
+  // Closing the channel above prevents the callback delegate from being called
+  // so it is now safe to release all callback state.
+  connect_callbacks_.reset(NULL);
+  receive_callbacks_.reset(NULL);
+  empty_queue(receive_queue_);
+  empty_queue(send_queue_);
 }
 
-// static
-scoped_refptr<BluetoothSocket> BluetoothSocketMac::CreateBluetoothSocket(
-    IOBluetoothSDPServiceRecord* record) {
-  BluetoothSocketMac* bluetooth_socket = NULL;
+void BluetoothSocketMac::Connect(
+    const base::Closure& success_callback,
+    const ErrorCompletionCallback& error_callback) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
+
+  if (connecting()) {
+    error_callback.Run(kSocketConnecting);
+    return;
+  }
+
+  if (rfcomm_channel_ != nil) {
+    error_callback.Run(kSocketAlreadyConnected);
+    return;
+  }
+
   uint8 rfcomm_channel_id;
-  if ([record getRFCOMMChannelID:&rfcomm_channel_id] == kIOReturnSuccess) {
-    IOBluetoothDevice* device = [record device];
-    IOBluetoothRFCOMMChannel* rfcomm_channel;
-    IOReturn status =
-        [device openRFCOMMChannelAsync:&rfcomm_channel
-                         withChannelID:rfcomm_channel_id
-                              delegate:nil];
-    if (status == kIOReturnSuccess) {
-      bluetooth_socket = new BluetoothSocketMac(rfcomm_channel);
-    } else {
-      LOG(ERROR) << "Failed to connect bluetooth socket ("
+  IOReturn status = [record_ getRFCOMMChannelID:&rfcomm_channel_id];
+  if (status != kIOReturnSuccess) {
+    // TODO(youngki) add support for L2CAP sockets as well.
+    error_callback.Run(kL2CAPNotSupported);
+    return;
+  }
+
+  IOBluetoothDevice* device = [record_ device];
+  IOBluetoothRFCOMMChannel* rfcomm_channel;
+  status = [device openRFCOMMChannelAsync:&rfcomm_channel
+                            withChannelID:rfcomm_channel_id
+                                 delegate:delegate_];
+  if (status != kIOReturnSuccess) {
+    std::stringstream error;
+    error << std::string("Failed to connect bluetooth socket (")
           << base::SysNSStringToUTF8([device addressString]) << "): (" << status
-          << ")";
-    }
+          << std::string(")");
+    error_callback.Run(error.str());
+    return;
   }
 
-  // TODO(youngki): Add support for L2CAP sockets as well.
+  connect_callbacks_.reset(new ConnectCallbacks());
+  connect_callbacks_->success_callback = success_callback;
+  connect_callbacks_->error_callback = error_callback;
+  rfcomm_channel_ = rfcomm_channel;
+  [rfcomm_channel_ setDelegate:delegate_];
+}
+
+void BluetoothSocketMac::OnChannelOpened(
+    IOBluetoothRFCOMMChannel* rfcomm_channel,
+    IOReturn status) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
+  DCHECK(rfcomm_channel_ == rfcomm_channel);
+  DCHECK(connecting());
+
+  scoped_ptr<ConnectCallbacks> temp = connect_callbacks_.Pass();
+  if (status != kIOReturnSuccess) {
+    ReleaseChannel();
+    std::stringstream error;
+    error << "Failed to connect bluetooth socket ("
+          << base::SysNSStringToUTF8([[record_ device] addressString]) << "): ("
+          << status << ")";
+    temp->error_callback.Run(error.str());
+    return;
+  }
 
-  return scoped_refptr<BluetoothSocketMac>(bluetooth_socket);
+  temp->success_callback.Run();
 }
 
-void BluetoothSocketMac::Close() { NOTIMPLEMENTED(); }
+void BluetoothSocketMac::Close() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
+
+  ReleaseChannel();
+}
 
 void BluetoothSocketMac::Disconnect(const base::Closure& callback) {
-  NOTIMPLEMENTED();
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
+
+  ReleaseChannel();
+  callback.Run();
 }
 
 void BluetoothSocketMac::Receive(
     int count,
     const ReceiveCompletionCallback& success_callback,
     const ReceiveErrorCompletionCallback& error_callback) {
-  NOTIMPLEMENTED();
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
+
+  if (connecting()) {
+    error_callback.Run(BluetoothSocket::kSystemError, kSocketConnecting);
+    return;
+  }
+
+  if (rfcomm_channel_ == nil) {
+    error_callback.Run(BluetoothSocket::kDisconnected, kSocketNotConnected);
+    return;
+  }
+
+  // Only one pending read at a time
+  if (receive_callbacks_) {
+    error_callback.Run(BluetoothSocket::kIOPending, kReceivePending);
+    return;
+  }
+
+  // If there is at least one packet, consume it and succeed right away.
+  if (!receive_queue_.empty()) {
+    scoped_refptr<net::IOBufferWithSize> buffer = receive_queue_.front();
+    receive_queue_.pop();
+    success_callback.Run(buffer->size(), buffer);
+    return;
+  }
+
+  // Set the receive callback to use when data is received.
+  receive_callbacks_.reset(new ReceiveCallbacks());
+  receive_callbacks_->success_callback = success_callback;
+  receive_callbacks_->error_callback = error_callback;
+}
+
+void BluetoothSocketMac::OnChannelDataReceived(
+    IOBluetoothRFCOMMChannel* rfcomm_channel,
+    void* data,
+    size_t length) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
+  DCHECK(rfcomm_channel_ == rfcomm_channel);
+  DCHECK(!connecting());
+  CHECK_LT(length, static_cast<size_t>(std::numeric_limits<int>::max()));
+
+  int data_size = static_cast<int>(length);
+  scoped_refptr<net::IOBufferWithSize> buffer(
+      new net::IOBufferWithSize(data_size));
+  memcpy(buffer->data(), data, buffer->size());
+
+  // If there is a pending read callback, call it now.
+  if (receive_callbacks_) {
+    scoped_ptr<ReceiveCallbacks> temp = receive_callbacks_.Pass();
+    temp->success_callback.Run(buffer->size(), buffer);
+    return;
+  }
+
+  // Otherwise, enqueue the buffer for later use
+  receive_queue_.push(buffer);
 }
 
 void BluetoothSocketMac::Send(scoped_refptr<net::IOBuffer> buffer,
                               int buffer_size,
                               const SendCompletionCallback& success_callback,
                               const ErrorCompletionCallback& error_callback) {
-  NOTIMPLEMENTED();
-}
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
+
+  if (connecting()) {
+    error_callback.Run(kSocketConnecting);
+    return;
+  }
 
-#if 0
-bool BluetoothSocketMac::Receive(net::GrowableIOBuffer* buffer) {
-  CHECK(buffer->offset() == 0);
-  int length = incoming_data_buffer_->offset();
-  if (length > 0) {
-    buffer->SetCapacity(length);
-    memcpy(buffer->data(), incoming_data_buffer_->StartOfBuffer(), length);
-    buffer->set_offset(length);
+  if (rfcomm_channel_ == nil) {
+    error_callback.Run(kSocketNotConnected);
+    return;
+  }
 
-    ResetIncomingDataBuffer();
+  // Create and enqueue request in preparation of async writes.
+  linked_ptr<SendRequest> request(new SendRequest());
+  request->buffer_size = buffer_size;
+  request->success_callback = success_callback;
+  request->error_callback = error_callback;
+  send_queue_.push(request);
+
+  // |writeAsync| accepts buffers of max. mtu bytes per call, so we need to emit
+  // multiple write operations if buffer_size > mtu.
+  BluetoothRFCOMMMTU mtu = [rfcomm_channel_ getMTU];
+  scoped_refptr<net::DrainableIOBuffer> send_buffer(
+      new net::DrainableIOBuffer(buffer, buffer_size));
+  while (send_buffer->BytesRemaining() > 0) {
+    int byte_count = send_buffer->BytesRemaining();
+    if (byte_count > mtu)
+      byte_count = mtu;
+    IOReturn status = [rfcomm_channel_ writeAsync:send_buffer->data()
+                                           length:byte_count
+                                           refcon:request.get()];
+    if (status != kIOReturnSuccess) {
+      std::stringstream error;
+      error << "Failed to connect bluetooth socket ("
+            << base::SysNSStringToUTF8([[record_ device] addressString])
+            << "): (" << status << ")";
+      // Remember the first error only
+      if (request->status == kIOReturnSuccess)
+        request->status = status;
+      request->error_signaled = true;
+      request->error_callback.Run(error.str());
+      // We may have failed to issue any write operation. In that case, there
+      // will be no corresponding completion callback for this particular
+      // request, so we must forget about it now.
+      if (request->active_async_writes == 0) {
+        send_queue_.pop();
+      }
+      return;
+    }
+
+    request->active_async_writes++;
+    send_buffer->DidConsume(byte_count);
   }
-  return true;
 }
 
-bool BluetoothSocketMac::Send(net::DrainableIOBuffer* buffer) {
-  int bytes_written = buffer->BytesRemaining();
-  IOReturn status = [rfcomm_channel_ writeAsync:buffer->data()
-                                         length:bytes_written
-                                         refcon:nil];
+void BluetoothSocketMac::OnChannelWriteComplete(
+    IOBluetoothRFCOMMChannel* rfcomm_channel,
+    void* refcon,
+    IOReturn status) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
+
+  // Note: We use "CHECK" below to ensure we never run into unforeseen
+  // occurrences of asynchronous callbacks, which could lead to data
+  // corruption.
+  CHECK(rfcomm_channel_ == rfcomm_channel);
+  CHECK(static_cast<SendRequest*>(refcon) == send_queue_.front().get());
+
+  // Keep a local linked_ptr to avoid releasing the request too early if we end
+  // up removing it from the queue.
+  linked_ptr<SendRequest> request = send_queue_.front();
+
+  // Remember the first error only
   if (status != kIOReturnSuccess) {
-    error_message_ = base::StringPrintf(
-        "Failed to send data. IOReturn code: %u", status);
-    return false;
+    if (request->status == kIOReturnSuccess)
+      request->status = status;
   }
 
-  buffer->DidConsume(bytes_written);
-  return true;
+  // Figure out if we are done with this async request
+  request->active_async_writes--;
+  if (request->active_async_writes > 0)
+    return;
+
+  // If this was the last active async write for this request, remove it from
+  // the queue and call the appropriate callback associated to the request.
+  send_queue_.pop();
+  if (request->status != kIOReturnSuccess) {
+    if (!request->error_signaled) {
+      std::stringstream error;
+      error << "Failed to connect bluetooth socket ("
+            << base::SysNSStringToUTF8([[record_ device] addressString])
+            << "): (" << status << ")";
+      request->error_signaled = true;
+      request->error_callback.Run(error.str());
+    }
+  } else {
+    request->success_callback.Run(request->buffer_size);
+  }
 }
 
-std::string BluetoothSocketMac::GetLastErrorMessage() const {
-  return error_message_;
-}
-#endif
-void BluetoothSocketMac::OnDataReceived(
-    IOBluetoothRFCOMMChannel* rfcomm_channel, void* data, size_t length) {
+void BluetoothSocketMac::OnChannelClosed(
+    IOBluetoothRFCOMMChannel* rfcomm_channel) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
   DCHECK(rfcomm_channel_ == rfcomm_channel);
-  CHECK_LT(length, static_cast<size_t>(std::numeric_limits<int>::max()));
-  int data_size = static_cast<int>(length);
-  if (incoming_data_buffer_->RemainingCapacity() < data_size) {
-    int additional_capacity =
-        std::max(data_size, incoming_data_buffer_->capacity());
-    CHECK_LT(
-        additional_capacity,
-        std::numeric_limits<int>::max() - incoming_data_buffer_->capacity());
-    incoming_data_buffer_->SetCapacity(
-        incoming_data_buffer_->capacity() + additional_capacity);
-  }
-  memcpy(incoming_data_buffer_->data(), data, data_size);
-  incoming_data_buffer_->set_offset(
-      incoming_data_buffer_->offset() + data_size);
-}
-
-void BluetoothSocketMac::ResetIncomingDataBuffer() {
-  incoming_data_buffer_ = new net::GrowableIOBuffer();
-  incoming_data_buffer_->SetCapacity(1024);
+
+  if (receive_callbacks_) {
+    scoped_ptr<ReceiveCallbacks> temp = receive_callbacks_.Pass();
+    temp->error_callback.Run(BluetoothSocket::kDisconnected,
+                             kSocketNotConnected);
+  }
+
+  ReleaseChannel();
 }
 
 }  // namespace device