Pepper gamepad support

BUG=79098


Review URL: http://codereview.chromium.org/9085027

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@117077 0039d316-1c4b-4281-b951-d872f2087c98

5 files changed, 63 insertions, 3 deletions

diff --git a/webkit/plugins/ppapi/mock_plugin_delegate.cc b/webkit/plugins/ppapi/mock_plugin_delegate.cc
index a991c50..da371c54 100644
--- a/webkit/plugins/ppapi/mock_plugin_delegate.cc
+++ b/webkit/plugins/ppapi/mock_plugin_delegate.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -8,6 +8,7 @@
 #include "base/message_loop_proxy.h"
 #include "ppapi/c/pp_errors.h"
 #include "ppapi/shared_impl/ppapi_preferences.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebGamepads.h"
 #include "webkit/plugins/ppapi/ppapi_plugin_instance.h"
 
 namespace webkit {
@@ -361,6 +362,10 @@ void MockPluginDelegate::DidChangeCursor(PluginInstance* instance,
 void MockPluginDelegate::DidReceiveMouseEvent(PluginInstance* instance) {
 }
 
+void MockPluginDelegate::SampleGamepads(WebKit::WebGamepads* data) {
+  data->length = 0;
+}
+
 bool MockPluginDelegate::IsInFullscreenMode() {
   return false;
 }
diff --git a/webkit/plugins/ppapi/mock_plugin_delegate.h b/webkit/plugins/ppapi/mock_plugin_delegate.h
index 7fe0155..fbd961a 100644
--- a/webkit/plugins/ppapi/mock_plugin_delegate.h
+++ b/webkit/plugins/ppapi/mock_plugin_delegate.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -153,6 +153,7 @@ class MockPluginDelegate : public PluginDelegate {
   virtual void DidChangeCursor(PluginInstance* instance,
                                const WebKit::WebCursorInfo& cursor);
   virtual void DidReceiveMouseEvent(PluginInstance* instance);
+  virtual void SampleGamepads(WebKit::WebGamepads* data) OVERRIDE;
   virtual bool IsInFullscreenMode();
   virtual bool IsPageVisible() const;
 };
diff --git a/webkit/plugins/ppapi/plugin_delegate.h b/webkit/plugins/ppapi/plugin_delegate.h
index af93ec8..6f9a17e 100644
--- a/webkit/plugins/ppapi/plugin_delegate.h
+++ b/webkit/plugins/ppapi/plugin_delegate.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -59,6 +59,7 @@ class PlatformCanvas;
 
 namespace WebKit {
 class WebFileChooserCompletion;
+class WebGamepads;
 struct WebCursorInfo;
 struct WebFileChooserParams;
 }
@@ -515,6 +516,9 @@ class PluginDelegate {
   // Determines if the browser entered fullscreen mode.
   virtual bool IsInFullscreenMode() = 0;
 
+  // Retrieve current gamepad data.
+  virtual void SampleGamepads(WebKit::WebGamepads* data) = 0;
+
   // Returns true if the containing page is visible.
   virtual bool IsPageVisible() const = 0;
 };
diff --git a/webkit/plugins/ppapi/ppapi_plugin_instance.cc b/webkit/plugins/ppapi/ppapi_plugin_instance.cc
index 63536bc..b3782d3 100644
--- a/webkit/plugins/ppapi/ppapi_plugin_instance.cc
+++ b/webkit/plugins/ppapi/ppapi_plugin_instance.cc
@@ -14,6 +14,7 @@
 #include "base/utf_string_conversions.h"
 #include "ppapi/c/dev/ppb_console_dev.h"
 #include "ppapi/c/dev/ppb_find_dev.h"
+#include "ppapi/c/dev/ppb_gamepad_dev.h"
 #include "ppapi/c/dev/ppb_zoom_dev.h"
 #include "ppapi/c/dev/ppp_find_dev.h"
 #include "ppapi/c/dev/ppp_selection_dev.h"
@@ -45,6 +46,7 @@
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebDocument.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebElement.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebFrame.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebGamepads.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebInputEvent.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebPluginContainer.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebSecurityOrigin.h"
@@ -226,6 +228,13 @@ COMPILE_ASSERT_MATCHING_ENUM(TypeGrabbing, PP_CURSORTYPE_GRABBING);
 // Do not assert WebCursorInfo::TypeCustom == PP_CURSORTYPE_CUSTOM;
 // PP_CURSORTYPE_CUSTOM is pinned to allow new cursor types.
 
+// Ensure conversion from WebKit::WebGamepads to PP_GamepadsData_Dev is safe.
+// See also DCHECKs in SampleGamepads below.
+COMPILE_ASSERT(sizeof(WebKit::WebGamepads) == sizeof(PP_GamepadsData_Dev),
+               size_difference);
+COMPILE_ASSERT(sizeof(WebKit::WebGamepad) == sizeof(PP_GamepadData_Dev),
+               size_difference);
+
 // Sets |*security_origin| to be the WebKit security origin associated with the
 // document containing the given plugin instance. On success, returns true. If
 // the instance is invalid, returns false and |*security_origin| will be
@@ -1310,6 +1319,42 @@ int32_t PluginInstance::Navigate(PPB_URLRequestInfo_Impl* request,
   return PP_OK;
 }
 
+void PluginInstance::SampleGamepads(PP_Instance instance,
+                                    PP_GamepadsData_Dev* data) {
+
+  // Because the WebKit objects have trivial ctors, using offsetof doesn't
+  // work. Instead use this version based on src/v8/src/globals.h. This
+  // workaround doesn't work in constant expressions as required for
+  // COMPILE_ASSERT, so DCHECK instead.
+
+#define OFFSET_OF(type, field) \
+  (reinterpret_cast<intptr_t>(&(reinterpret_cast<type*>(4)->field)) - 4)
+
+#define DCHECK_GAMEPADS_OFFSET(webkit_name, pp_name) \
+  DCHECK(OFFSET_OF(WebKit::WebGamepads, webkit_name) \
+             == OFFSET_OF(PP_GamepadsData_Dev, pp_name))
+
+#define DCHECK_GAMEPAD_OFFSET(webkit_name, pp_name) \
+  DCHECK(OFFSET_OF(WebKit::WebGamepad, webkit_name) \
+             == OFFSET_OF(PP_GamepadData_Dev, pp_name))
+
+  DCHECK_GAMEPADS_OFFSET(length, length);
+  DCHECK_GAMEPADS_OFFSET(items, items);
+  DCHECK_GAMEPAD_OFFSET(connected, connected);
+  DCHECK_GAMEPAD_OFFSET(id, id);
+  DCHECK_GAMEPAD_OFFSET(timestamp, timestamp);
+  DCHECK_GAMEPAD_OFFSET(axesLength, axes_length);
+  DCHECK_GAMEPAD_OFFSET(axes, axes);
+  DCHECK_GAMEPAD_OFFSET(buttonsLength, buttons_length);
+  DCHECK_GAMEPAD_OFFSET(buttons, buttons);
+
+#undef OFFSET_OF
+#undef DCHECK_GAMEPADS_OFFSET
+#undef DCHECK_GAMEPAD_OFFSET
+
+  delegate()->SampleGamepads(reinterpret_cast<WebKit::WebGamepads*>(data));
+}
+
 bool PluginInstance::IsViewAccelerated() {
   if (!container_)
     return false;
diff --git a/webkit/plugins/ppapi/ppapi_plugin_instance.h b/webkit/plugins/ppapi/ppapi_plugin_instance.h
index cbafec1..3caef5c 100644
--- a/webkit/plugins/ppapi/ppapi_plugin_instance.h
+++ b/webkit/plugins/ppapi/ppapi_plugin_instance.h
@@ -16,6 +16,7 @@
 #include "base/string16.h"
 #include "googleurl/src/gurl.h"
 #include "ppapi/c/dev/pp_cursor_type_dev.h"
+#include "ppapi/c/dev/ppb_gamepad_dev.h"
 #include "ppapi/c/dev/ppp_printing_dev.h"
 #include "ppapi/c/dev/ppp_find_dev.h"
 #include "ppapi/c/dev/ppp_selection_dev.h"
@@ -287,6 +288,10 @@ class WEBKIT_PLUGINS_EXPORT PluginInstance :
                    const char* target,
                    bool from_user_action);
 
+  // Implementation of PPB_Gamepad.
+  void SampleGamepads(PP_Instance instance, PP_GamepadsData_Dev* data)
+      OVERRIDE;
+
   // Implementation of PPP_Messaging.
   void HandleMessage(PP_Var message);