Adds the UserInputMonitor implementation for Mac.

media/base/user_input_monitor_mac.cc

+// Copyright 2013 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 "media/base/user_input_monitor.h"
+
+#include <ApplicationServices/ApplicationServices.h>
+
+#include "base/bind.h"
+#include "base/logging.h"
+#include "base/mac/scoped_cftyperef.h"
+#include "base/message_loop/message_loop.h"
+#include "base/single_thread_task_runner.h"
+#include "base/time/time.h"
+#include "base/timer/timer.h"
+#include "third_party/skia/include/core/SkPoint.h"
+
+namespace media {
+namespace {
+
+class UserInputMonitorMac : public UserInputMonitor {
+ public:
+  explicit UserInputMonitorMac(
+      scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner);
+  virtual ~UserInputMonitorMac();
+
+  virtual size_t GetKeyPressCount() const OVERRIDE;
+
+ private:
+  static CGEventRef MouseMoved(CGEventTapProxy proxy,
+                               CGEventType type,
+                               CGEventRef event,
+                               void* context);
+
+  virtual void StartMouseMonitoring() OVERRIDE;
+  virtual void StopMouseMonitoring() OVERRIDE;
+  virtual void StartKeyboardMonitoring() OVERRIDE;
+  virtual void StopKeyboardMonitoring() OVERRIDE;
+
+  // Task runner on which input events are received.
+  scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner_;
+
+  // These members should only be accessed on the UI thread.
+  base::ScopedCFTypeRef<CFRunLoopSourceRef> input_run_loop_source_;
+  base::ScopedCFTypeRef<CFMachPortRef> input_mach_port_;
+
+  size_t initial_key_press_count_;
+
+  DISALLOW_COPY_AND_ASSIGN(UserInputMonitorMac);
+};
+
+UserInputMonitorMac::UserInputMonitorMac(
+    scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner)
+    : ui_task_runner_(ui_task_runner),
+      initial_key_press_count_(0) {}
+
+UserInputMonitorMac::~UserInputMonitorMac() {
+  DCHECK(!input_mach_port_);
+  DCHECK(!input_run_loop_source_);
+  DCHECK(!initial_key_press_count_);
+}
+
+size_t UserInputMonitorMac::GetKeyPressCount() const {
+  size_t total_count = CGEventSourceCounterForEventType(
+      kCGEventSourceStateHIDSystemState, kCGEventKeyDown);
+  return total_count - initial_key_press_count_;
+}
+
+CGEventRef UserInputMonitorMac::MouseMoved(CGEventTapProxy proxy,
+                                           CGEventType type,
+                                           CGEventRef event,
+                                           void* context) {
+  DCHECK_EQ(base::MessageLoop::TYPE_UI, base::MessageLoop::current()->type());
+
+  int64_t pid = CGEventGetIntegerValueField(event, kCGEventSourceUnixProcessID);
+  // |pid| 0 means the event is generated by hardware.
+  if (pid == 0) {
+    DCHECK_EQ(kCGEventMouseMoved, type);
+    CGPoint cg_mouse_pos = CGEventGetLocation(event);
+    SkIPoint mouse_pos = SkIPoint::Make(cg_mouse_pos.x, cg_mouse_pos.y);
+    static_cast<UserInputMonitorMac*>(context)->OnMouseEvent(mouse_pos);
+  }
+  return NULL;
+}
+
+void UserInputMonitorMac::StartMouseMonitoring() {
+  if (!ui_task_runner_->BelongsToCurrentThread()) {
+    ui_task_runner_->PostTask(
+        FROM_HERE,
+        base::Bind(&UserInputMonitorMac::StartMouseMonitoring,
+                   base::Unretained(this)));
+    return;
+  }
+  input_mach_port_.reset(CGEventTapCreate(kCGSessionEventTap,
+                                          kCGHeadInsertEventTap,
+                                          kCGEventTapOptionListenOnly,
+                                          CGEventMaskBit(kCGEventMouseMoved),
+                                          MouseMoved,
+                                          this));
+  if (input_mach_port_) {
+    input_run_loop_source_.reset(
+        CFMachPortCreateRunLoopSource(NULL, input_mach_port_, 0));
+    CFRunLoopAddSource(
+        CFRunLoopGetMain(), input_run_loop_source_, kCFRunLoopCommonModes);
+  } else {
+    LOG(ERROR) << "CGEventTapCreate failed.";
+  }
+}
+
+void UserInputMonitorMac::StopMouseMonitoring() {
+  if (!ui_task_runner_->BelongsToCurrentThread()) {
+    ui_task_runner_->PostTask(
+        FROM_HERE,
+        base::Bind(&UserInputMonitorMac::StopMouseMonitoring,
+                   base::Unretained(this)));
+    return;
+  }
+  if (input_run_loop_source_) {
+    CFMachPortInvalidate(input_mach_port_);
+    CFRunLoopRemoveSource(
+        CFRunLoopGetMain(), input_run_loop_source_, kCFRunLoopCommonModes);
+    input_run_loop_source_.reset();
+    input_mach_port_.reset();
+  }
+}
+
+void UserInputMonitorMac::StartKeyboardMonitoring() {
+  initial_key_press_count_ = CGEventSourceCounterForEventType(
+      kCGEventSourceStateHIDSystemState, kCGEventKeyDown);
+}
+
+void UserInputMonitorMac::StopKeyboardMonitoring() {
+  initial_key_press_count_ = 0;
+}
+
+}  // namespace
+
+scoped_ptr<UserInputMonitor> UserInputMonitor::Create(
+    const scoped_refptr<base::SingleThreadTaskRunner>& input_task_runner,
+    const scoped_refptr<base::SingleThreadTaskRunner>& ui_task_runner) {
+  return scoped_ptr<UserInputMonitor>(new UserInputMonitorMac(ui_task_runner));
+}
+
+}  // namespace media