Implemented BluetoothTaskManagerWin class.

device/bluetooth/bluetooth_task_manager_win.cc

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "device/bluetooth/bluetooth_task_manager_win.h"
+
+#include <BluetoothAPIs.h>
+#if defined(_WIN32_WINNT_WIN8) && _MSC_VER < 1700
+// The Windows 8 SDK defines FACILITY_VISUALCPP in winerror.h.
+#undef FACILITY_VISUALCPP
+#endif
+#include <delayimp.h>
+#include <string>
+
+#include "base/bind.h"
+#include "base/memory/ref_counted.h"
+#include "base/message_loop.h"
+#include "base/sequenced_task_runner.h"
+#include "base/stringprintf.h"
+#include "base/sys_string_conversions.h"
+#include "base/threading/sequenced_worker_pool.h"
+#include "base/threading/thread_restrictions.h"
+

[grt (UTC plus 2), 2013/01/10 04:01:47]

#include "base/win/scoped_handle.h"

[youngki, 2013/01/11 20:00:25]

Done.

+#pragma comment(lib, "Bthprops.lib")
+
+namespace {
+
+const int kNumThreadsInWorkerPool = 3;
+const char* kBluetoothThreadName = "BluetoothPollingThreadWin";

[grt (UTC plus 2), 2013/01/10 04:01:47]

const char kBluetoothThreadName[] = "...";

[youngki, 2013/01/11 20:00:25]

Done.

+const BLUETOOTH_FIND_RADIO_PARAMS adapter_param =

[grt (UTC plus 2), 2013/01/10 04:01:47]

since this is a constant, how about kEmptyAdapterParam or somesuch? actually,
what's the benefit of this constant rather than making an instance on the stack
in PollAdapter?

[youngki, 2013/01/11 20:00:25]

Moved it into PollAdapter.

+    { sizeof(BLUETOOTH_FIND_RADIO_PARAMS) };
+
+// A frame-based exception handler filter function for a handler for exceptions
+// generated by the Visual C++ delay loader helper function.
+int FilterVisualCPPExceptions(DWORD exception_code) {
+  return HRESULT_FACILITY(exception_code) == FACILITY_VISUALCPP ?
+      EXCEPTION_EXECUTE_HANDLER : EXCEPTION_CONTINUE_SEARCH;
+}  // namespace
+
+// Returns true if the machine has a bluetooth stack available. The first call
+// to this function will involve file IO, so it should be done on an
+// appropriate thread. This function is not threadsafe.
+bool HasBluetoothStack() {
+  static enum {
+    HBS_UNKNOWN,
+    HBS_YES,
+    HBS_NO,
+  } has_bluetooth_stack = HBS_UNKNOWN;
+
+  if (has_bluetooth_stack == HBS_UNKNOWN) {
+    base::ThreadRestrictions::AssertIOAllowed();
+    HRESULT hr = E_FAIL;
+    __try {
+      hr = __HrLoadAllImportsForDll("bthprops.cpl");
+    } __except(FilterVisualCPPExceptions(::GetExceptionCode())) {
+      hr = E_FAIL;
+    }
+    has_bluetooth_stack = SUCCEEDED(hr) ? HBS_YES : HBS_NO;
+  }
+
+  return has_bluetooth_stack == HBS_YES;
+}
+
+// Populates bluetooth adapter state using adapter_handle.
+void GetAdapterState(const HANDLE adapter_handle,

[grt (UTC plus 2), 2013/01/10 04:01:47]

nit: no const

[youngki, 2013/01/11 20:00:25]

Done.

+                     device::BluetoothTaskManagerWin::AdapterState* state) {
+  std::string name;
+  std::string address;
+  bool powered = false;
+  BLUETOOTH_RADIO_INFO adapter_info = { sizeof(BLUETOOTH_RADIO_INFO), 0 };
+  if (adapter_handle &&
+      ERROR_SUCCESS == BluetoothGetRadioInfo(adapter_handle,
+                                             &adapter_info)) {
+    name = base::SysWideToUTF8(adapter_info.szName);
+    address = base::StringPrintf("%02X:%02X:%02X:%02X:%02X:%02X",
+        adapter_info.address.rgBytes[5],
+        adapter_info.address.rgBytes[4],
+        adapter_info.address.rgBytes[3],
+        adapter_info.address.rgBytes[2],
+        adapter_info.address.rgBytes[1],
+        adapter_info.address.rgBytes[0]);
+    powered = !!BluetoothIsConnectable(adapter_handle);
+  }
+  state->name = name;
+  state->address = address;
+  state->powered = powered;
+}
+
+}
+
+namespace device {
+
+// static
+const int BluetoothTaskManagerWin::kPollIntervalMs = 500;
+
+BluetoothTaskManagerWin::BluetoothTaskManagerWin()
+    : ui_task_runner_(MessageLoop::current()->message_loop_proxy()),

[grt (UTC plus 2), 2013/01/10 04:01:47]

i was under the impression that using ThreadTaskRunnerHandle::Get() to get the
current thread's SingleThreadTaskRunner is the new hotness (and that MLP was
deprecated).

[youngki, 2013/01/11 20:00:25]

Done. If that's the new hotness, I want to be in that group too. :)

+      worker_pool_(new base::SequencedWorkerPool(kNumThreadsInWorkerPool,
+                                                 kBluetoothThreadName)),
+      bluetooth_task_runner_(
+          worker_pool_->GetSequencedTaskRunnerWithShutdownBehavior(
+              worker_pool_->GetSequenceToken(),
+              base::SequencedWorkerPool::CONTINUE_ON_SHUTDOWN)) {
+}
+
+BluetoothTaskManagerWin::~BluetoothTaskManagerWin() {
+}
+
+void BluetoothTaskManagerWin::AddObserver(Observer* observer) {
+  CHECK(observer);

[grt (UTC plus 2), 2013/01/10 04:01:47]

why not DCHECK here and on line 115?

[youngki, 2013/01/11 20:00:25]

Done.

+  observers_.AddObserver(observer);
+}
+
+void BluetoothTaskManagerWin::RemoveObserver(Observer* observer) {
+  CHECK(observer);
+  observers_.RemoveObserver(observer);
+}
+
+void BluetoothTaskManagerWin::Initialize() {
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
+  bluetooth_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&BluetoothTaskManagerWin::StartPolling,
+                 this));
+}
+
+void BluetoothTaskManagerWin::StartPolling() {
+  DCHECK(bluetooth_task_runner_->RunsTasksOnCurrentThread());
+
+  // TODO(youngki): Handle this check where BluetoothAdapter is initialized.
+  if (HasBluetoothStack()) {
+    PollAdapter();
+  }
+}
+
+void BluetoothTaskManagerWin::Shutdown() {
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
+  worker_pool_->Shutdown();
+}
+
+void BluetoothTaskManagerWin::OnAdapterStateChanged(const AdapterState* state) {
+  DCHECK(ui_task_runner_->RunsTasksOnCurrentThread());
+  FOR_EACH_OBSERVER(BluetoothTaskManagerWin::Observer, observers_,
+                    AdapterStateChanged(*state));
+}
+
+void BluetoothTaskManagerWin::PollAdapter() {
+  DCHECK(bluetooth_task_runner_->RunsTasksOnCurrentThread());
+
+  HBLUETOOTH_RADIO_FIND adapter_handle = NULL;

[grt (UTC plus 2), 2013/01/10 04:01:47]

this has the wrong type and is being leaked. you should use a
base::win::ScopedHandle like so:
  base::win::ScopedHandle adapter_handler;

[youngki, 2013/01/11 20:00:25]

Done. I never knew about ScopedHandle. Thanks for letting me know..!

+  HBLUETOOTH_RADIO_FIND handle = BluetoothFindFirstRadio(&adapter_param,
+                                                         &adapter_handle);

[grt (UTC plus 2), 2013/01/10 04:01:47]

and change &adapter_handle to adapter_handle.Receive()

[youngki, 2013/01/11 20:00:25]

Done.

+
+  if (handle)
+    BluetoothFindRadioClose(handle);
+
+  AdapterState* state = new AdapterState();
+  GetAdapterState(adapter_handle, state);
+
+  // Notify the UI thread of the Bluetooth Adapter state.
+  ui_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&BluetoothTaskManagerWin::OnAdapterStateChanged,
+                 this,
+                 base::Owned(state)));
+
+  // Re-poll.
+  bluetooth_task_runner_->PostDelayedTask(
+      FROM_HERE,
+      base::Bind(&BluetoothTaskManagerWin::PollAdapter,
+                 this),
+      base::TimeDelta::FromMilliseconds(kPollIntervalMs));
+}
+
+}  // namespace device