Adds the UserInputMonitor implementation for Mac.

media/base/user_input_monitor_mac.mm

 // 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"
 
+#import <AppKit/AppKit.h>
+
+#include "base/bind.h"
+#include "base/compiler_specific.h"
+#include "base/location.h"
+#include "base/logging.h"
+#include "base/mac/scoped_cftyperef.h"
+#include "base/memory/ref_counted.h"
+#include "base/single_thread_task_runner.h"
+#include "base/threading/non_thread_safe.h"
+#include "third_party/skia/include/core/SkPoint.h"
+#import "third_party/GTM/AppKit/GTMCarbonEvent.h"
+
 namespace media {
-
-// TODO(jiayl): add the implementation.
+namespace {
+
+class UserInputMonitorMac : public base::NonThreadSafe,
+                            public UserInputMonitor {
+ public:
+  // Invoked by UserInputMonitorManager.
+  class EventHandler {

[Sergey Ulanov, 2013/08/20 00:55:41]

Do you need this interface? Can you just reference Core given that its' the only
EventHandler.

[jiayl, 2013/08/20 23:49:05]

I rearranged the code to get rid of the interface.

+   public:
+    virtual ~EventHandler() {}
+
+    virtual void OnMouseMoved(const SkIPoint& position) = 0;
+  };
+
+  UserInputMonitorMac(
+      scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner);
+
+  virtual ~UserInputMonitorMac();
+
+ private:
+  // The actual implementation resides in UserInputMonitorMac::Core class.
+  // Only called on the UI task runner.
+  class Core;
+  typedef const base::Callback<void(const SkIPoint&)> MouseCallback;
+
+  virtual void StartMouseMonitoring() OVERRIDE;
+  virtual void StopMouseMonitoring() OVERRIDE;
+  virtual void StartKeyboardMonitoring() OVERRIDE { NOTREACHED(); }
+  virtual void StopKeyboardMonitoring() OVERRIDE { NOTREACHED(); }
+
+  void OnMouseMoved(const SkIPoint& position);
+
+  // Task runner on which X Window events are received.
+  scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner_;
+
+  scoped_refptr<Core> core_;
+
+  DISALLOW_COPY_AND_ASSIGN(UserInputMonitorMac);
+};
+
+}  // namespace
+}  // namespace media
+
+@interface UserInputMonitorManager : NSObject {
+ @private
+  CFRunLoopSourceRef inputRunLoopSource_;
+  base::ScopedCFTypeRef<CFMachPortRef> inputMachPort_;
+  media::UserInputMonitorMac::EventHandler* monitor_;
+}
+
+- (id)initWithMonitor:(media::UserInputMonitorMac::EventHandler*)monitor;
+
+// Called when the local mouse moves.
+- (void)mouseMoved:(const SkIPoint&)mousePos;
+
+// Must be called when the UserInputMonitorManager is no longer to be used.

[DaleCurtis, 2013/08/19 23:49:00]

UserInputMonitorManager?

[jiayl, 2013/08/20 00:21:15]

Renamed

+// Similar to NSTimer in that more than a simple release is required.
+- (void)invalidate;
+
+@end
+
+static CGEventRef inputEvent(CGEventTapProxy proxy, CGEventType type,

[Sergey Ulanov, 2013/08/20 00:55:41]

nit: one argument per line please.

[jiayl, 2013/08/20 23:49:05]

Done.

+                             CGEventRef event, void* context) {

[Sergey Ulanov, 2013/08/20 00:55:41]

why is it void*?

[jiayl, 2013/08/20 23:49:05]

This is required by the CGEventTapCreate API.

+  int64_t pid = CGEventGetIntegerValueField(event, kCGEventSourceUnixProcessID);
+  if (pid == 0) {
+    DCHECK(type == kCGEventMouseMoved);
+    CGPoint cgMousePos = CGEventGetLocation(event);
+    SkIPoint mousePos = SkIPoint::Make(cgMousePos.x, cgMousePos.y);
+    [static_cast<UserInputMonitorManager*>(context) mouseMoved:mousePos];
+  }
+  return NULL;
+}
+
+@implementation UserInputMonitorManager
+
+- (id)initWithMonitor:(media::UserInputMonitorMac::EventHandler*)monitor {
+  if ((self = [super init])) {
+    monitor_ = monitor;
+    inputMachPort_.reset(CGEventTapCreate(
+        kCGSessionEventTap, kCGHeadInsertEventTap, kCGEventTapOptionListenOnly,
+        CGEventMaskBit(kCGEventMouseMoved), inputEvent, self));
+    if (inputMachPort_) {
+      inputRunLoopSource_ = CFMachPortCreateRunLoopSource(
+          NULL, inputMachPort_, 0);
+      CFRunLoopAddSource(
+          CFRunLoopGetMain(), inputRunLoopSource_, kCFRunLoopCommonModes);
+    } else {
+      LOG(ERROR) << "CGEventTapCreate failed.";
+    }
+    if (!inputMachPort_) {
+      [self release];
+      return nil;
+    }
+  }
+  return self;
+}
+
+- (void)mouseMoved:(const SkIPoint&)mousePos {
+  monitor_->OnMouseMoved(mousePos);
+}
+
+- (void)invalidate {
+  if (inputRunLoopSource_) {
+    CFMachPortInvalidate(inputMachPort_);
+    CFRunLoopRemoveSource(
+        CFRunLoopGetMain(), inputRunLoopSource_, kCFRunLoopCommonModes);
+    CFRelease(inputRunLoopSource_);
+    inputMachPort_.reset(0);

[Sergey Ulanov, 2013/08/20 00:55:41]

remove 0 - it's default.

[jiayl, 2013/08/20 23:49:05]

Done.

+    inputRunLoopSource_ = NULL;
+  }
+}
+
+@end
+
+namespace media {
+namespace {
+
+class UserInputMonitorMac::Core
+    : public base::RefCountedThreadSafe<Core>,
+      public EventHandler {
+ public:
+  Core(const MouseCallback& callback);
+
+  void Start();
+  void Stop();
+
+ private:
+  friend class base::RefCountedThreadSafe<Core>;
+  virtual ~Core();
+
+  // EventHandler interface.
+  virtual void OnMouseMoved(const SkIPoint& position) OVERRIDE;
+
+  MouseCallback callback_;
+  UserInputMonitorManager* manager_;
+
+  DISALLOW_COPY_AND_ASSIGN(Core);
+};
+
+UserInputMonitorMac::UserInputMonitorMac(
+    scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner)
+    : ui_task_runner_(ui_task_runner),
+      core_(new Core(base::Bind(&UserInputMonitorMac::OnMouseMoved,
+                                base::Unretained(this)))) {}
+
+UserInputMonitorMac::~UserInputMonitorMac() {}
+
+void UserInputMonitorMac::StartMouseMonitoring() {
+  ui_task_runner_->PostTask(
+      FROM_HERE, base::Bind(&Core::Start, core_.get()));
+}
+
+void UserInputMonitorMac::StopMouseMonitoring() {
+  ui_task_runner_->PostTask(
+      FROM_HERE, base::Bind(&Core::Stop, core_.get()));
+}
+
+void UserInputMonitorMac::OnMouseMoved(const SkIPoint& position) {
+  UserInputMonitor::OnMouseEvent(position);
+}
+
+UserInputMonitorMac::Core::Core(const MouseCallback& callback)
+    : callback_(callback), manager_(nil) {}
+
+void UserInputMonitorMac::Core::Start() {
+  manager_ = [[UserInputMonitorManager alloc] initWithMonitor:this];
+}
+
+void UserInputMonitorMac::Core::Stop() {
+  [manager_ invalidate];
+  [manager_ release];
+  manager_ = nil;
+}
+
+UserInputMonitorMac::Core::~Core() {
+  DCHECK(manager_ == nil);
+}
+
+void UserInputMonitorMac::Core::OnMouseMoved(const SkIPoint& position) {
+  callback_.Run(position);
+}
+
+}  // 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>();
+  return scoped_ptr<UserInputMonitor>(new UserInputMonitorMac(ui_task_runner));
 }
 
 }  // namespace media