Pepper gamepad support

webkit/plugins/ppapi/ppapi_plugin_instance.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 "webkit/plugins/ppapi/ppapi_plugin_instance.h"
 
 #include "base/bind.h"
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "base/memory/linked_ptr.h"
 #include "base/message_loop.h"
 #include "base/stringprintf.h"
 #include "base/utf_offset_string_conversions.h"
 #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"
 #include "ppapi/c/dev/ppp_zoom_dev.h"
 #include "ppapi/c/pp_rect.h"
 #include "ppapi/c/ppb_core.h"
 #include "ppapi/c/ppp_input_event.h"
 #include "ppapi/c/ppp_instance.h"
 #include "ppapi/c/ppp_messaging.h"
 #include "ppapi/c/ppp_mouse_lock.h"
@@ skipping 11 matching lines @@
 #include "printing/units.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkRect.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebBindings.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebCompositionUnderline.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebConsoleMessage.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebCursorInfo.h"
 #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"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebString.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebURL.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebURLRequest.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebView.h"
 #include "webkit/plugins/ppapi/common.h"
 #include "webkit/plugins/ppapi/event_conversion.h"
 #include "webkit/plugins/ppapi/fullscreen_container.h"
@@ skipping 161 matching lines @@
 COMPILE_ASSERT_MATCHING_ENUM(TypeCopy, PP_CURSORTYPE_COPY);
 COMPILE_ASSERT_MATCHING_ENUM(TypeNone, PP_CURSORTYPE_NONE);
 COMPILE_ASSERT_MATCHING_ENUM(TypeNotAllowed, PP_CURSORTYPE_NOTALLOWED);
 COMPILE_ASSERT_MATCHING_ENUM(TypeZoomIn, PP_CURSORTYPE_ZOOMIN);
 COMPILE_ASSERT_MATCHING_ENUM(TypeZoomOut, PP_CURSORTYPE_ZOOMOUT);
 COMPILE_ASSERT_MATCHING_ENUM(TypeGrab, PP_CURSORTYPE_GRAB);
 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
 // unchanged.
 bool SecurityOriginForInstance(PP_Instance instance_id,
                                WebKit::WebSecurityOrigin* security_origin) {
   PluginInstance* instance = HostGlobals::Get()->GetInstance(instance_id);
   if (!instance)
     return false;
 
@@ skipping 1064 matching lines @@
   // Only GETs and POSTs are supported.
   if (web_request.httpMethod() != "GET" &&
       web_request.httpMethod() != "POST")
     return PP_ERROR_BADARGUMENT;
 
   WebString target_str = WebString::fromUTF8(target);
   container_->loadFrameRequest(web_request, target_str, false, NULL);
   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;
 
   WebDocument document = container_->element().document();
   WebFrame* frame = document.frame();
   if (!frame)
     return false;
   WebView* view = frame->view();
   if (!view)
@@ skipping 731 matching lines @@
   screen_size_for_fullscreen_ = gfx::Size();
   WebElement element = container_->element();
   element.setAttribute(WebString::fromUTF8(kWidth), width_before_fullscreen_);
   element.setAttribute(WebString::fromUTF8(kHeight), height_before_fullscreen_);
   element.setAttribute(WebString::fromUTF8(kBorder), border_before_fullscreen_);
   element.setAttribute(WebString::fromUTF8(kStyle), style_before_fullscreen_);
 }
 
 }  // namespace ppapi
 }  // namespace webkit