Reland: Add code to deal with serial device disconnection detection on Windows

device/serial/serial_io_handler_win.cc

Index: device/serial/serial_io_handler_win.cc
diff --git a/device/serial/serial_io_handler_win.cc b/device/serial/serial_io_handler_win.cc
index cd1045107fe746e285d1bf422297236228339638..fba1bcedd0222a3fb16acfb3507a5c8ab10a50a3 100644
--- a/device/serial/serial_io_handler_win.cc
+++ b/device/serial/serial_io_handler_win.cc
@@ -2,9 +2,17 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "device/serial/serial_io_handler_win.h"
+
 #include <windows.h>
+#include <setupapi.h>
 
-#include "device/serial/serial_io_handler_win.h"
+#include "base/bind.h"
+#include "base/scoped_observer.h"
+#include "base/threading/thread_checker.h"
+#include "device/core/device_info_query_win.h"
+#include "device/core/device_monitor_win.h"
+#include "third_party/re2/re2/re2.h"
 
 namespace device {
 
@@ -130,6 +138,12 @@ serial::StopBits StopBitsConstantToEnum(int stop_bits) {
   }
 }
 
+// Searches for the COM port in the device's friendly name, assigns its value to
+// com_port, and returns whether the operation was successful.
+bool GetCOMPort(const std::string friendly_name, std::string* com_port) {
+  return RE2::PartialMatch(friendly_name, ".* \\((COM[0-9]+)\\)", com_port);
+}
+
 }  // namespace
 
 // static
@@ -139,6 +153,81 @@ scoped_refptr<SerialIoHandler> SerialIoHandler::Create(
   return new SerialIoHandlerWin(file_thread_task_runner, ui_thread_task_runner);
 }
 
+class SerialIoHandlerWin::UiThreadHelper : public DeviceMonitorWin::Observer {
+ public:
+  UiThreadHelper(
+      base::WeakPtr<SerialIoHandlerWin> io_handler,
+      scoped_refptr<base::SingleThreadTaskRunner> io_thread_task_runner)
+      : device_observer_(this),
+        io_handler_(io_handler),
+        io_thread_task_runner_(io_thread_task_runner) {}
+
+  ~UiThreadHelper() { DCHECK(thread_checker_.CalledOnValidThread()); }
+
+  static void Start(UiThreadHelper* self) {
+    self->thread_checker_.DetachFromThread();
+    DeviceMonitorWin* device_monitor = DeviceMonitorWin::GetForAllInterfaces();
+    if (device_monitor)
+      self->device_observer_.Add(device_monitor);
+  }
+
+ private:
+  // DeviceMonitorWin::Observer
+  void OnDeviceRemoved(const GUID& class_guid,
+                       const std::string& device_path) override {
+    DCHECK(thread_checker_.CalledOnValidThread());
+    io_thread_task_runner_->PostTask(
+        FROM_HERE, base::Bind(&SerialIoHandlerWin::OnDeviceRemoved, io_handler_,
+                              device_path));
+  }
+
+  base::ThreadChecker thread_checker_;
+  ScopedObserver<DeviceMonitorWin, DeviceMonitorWin::Observer> device_observer_;
+
+  // This weak pointer is only valid when checked on this task runner.
+  base::WeakPtr<SerialIoHandlerWin> io_handler_;
+  scoped_refptr<base::SingleThreadTaskRunner> io_thread_task_runner_;
+
+  DISALLOW_COPY_AND_ASSIGN(UiThreadHelper);
+};
+
+void SerialIoHandlerWin::OnDeviceRemoved(const std::string& device_path) {
+  DCHECK(CalledOnValidThread());
+
+  device::DeviceInfoQueryWin device_info_query;

[grt (UTC plus 2), 2015/11/17 16:06:56]

omit device::

[juncai, 2015/11/17 19:14:07]

Done.

+  if (!device_info_query.device_info_list_valid()) {
+    DVPLOG(1) << "Failed to create a device information set";
+    return;
+  }
+
+  // This will add the device so we can query driver info.
+  if (!device_info_query.AddDevice(device_path.c_str())) {
+    DVPLOG(1) << "Failed to get device interface data for " << device_path;
+    return;
+  }
+
+  if (!device_info_query.GetDeviceInfo()) {
+    DVPLOG(1) << "Failed to get device info for " << device_path;
+    return;
+  }
+
+  std::string friendly_name;
+  if (!device_info_query.GetDeviceStringProperty(SPDRP_FRIENDLYNAME,
+                                                 &friendly_name)) {
+    DVPLOG(1) << "Failed to get device service property";
+    return;
+  }
+
+  std::string com_port;
+  if (!GetCOMPort(friendly_name, &com_port)) {
+    DVPLOG(1) << "Failed to get port name from \"" << friendly_name << "\".";
+    return;
+  }
+
+  if (port() == com_port)
+    CancelRead(serial::RECEIVE_ERROR_DISCONNECTED);
+}
+
 bool SerialIoHandlerWin::PostOpen() {
   DCHECK(!comm_context_);
   DCHECK(!read_context_);
@@ -159,6 +248,13 @@ bool SerialIoHandlerWin::PostOpen() {
   write_context_->handler = this;
   memset(&write_context_->overlapped, 0, sizeof(write_context_->overlapped));
 
+  scoped_refptr<base::SingleThreadTaskRunner> io_thread_task_runner =
+      base::ThreadTaskRunnerHandle::Get();
+  helper_ =
+      new UiThreadHelper(weak_factory_.GetWeakPtr(), io_thread_task_runner);
+  ui_thread_task_runner()->PostTask(
+      FROM_HERE, base::Bind(&UiThreadHelper::Start, helper_));
+
   // A ReadIntervalTimeout of MAXDWORD will cause async reads to complete
   // immediately with any data that's available, even if there is none.
   // This is OK because we never issue a read request until WaitCommEvent
@@ -271,10 +367,11 @@ SerialIoHandlerWin::SerialIoHandlerWin(
     scoped_refptr<base::SingleThreadTaskRunner> ui_thread_task_runner)
     : SerialIoHandler(file_thread_task_runner, ui_thread_task_runner),
       event_mask_(0),
-      is_comm_pending_(false) {
-}
+      is_comm_pending_(false),
+      weak_factory_(this) {}
 
 SerialIoHandlerWin::~SerialIoHandlerWin() {
+  ui_thread_task_runner()->DeleteSoon(FROM_HERE, helper_);
 }
 
 void SerialIoHandlerWin::OnIOCompleted(