FBTF: Allow forward declaration of classes passed to sync IPC messages.

chrome/common/webkit_param_traits.h

 // Copyright (c) 2010 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.
 
 // This file contains ParamTraits templates to support serialization of WebKit
 // data types over IPC.
 //
 // NOTE: IT IS IMPORTANT THAT ONLY POD (plain old data) TYPES ARE SERIALIZED.
 //
 // There are several reasons for this restrictions:
 //
 //   o  We don't want inclusion of this file to imply linking to WebKit code.
 //
 //   o  Many WebKit structures are not thread-safe.  WebString, for example,
 //      contains a reference counted buffer, which does not use thread-safe
 //      reference counting.  If we allowed serializing WebString, then we may
 //      run the risk of introducing subtle thread-safety bugs if people passed a
 //      WebString across threads via PostTask(NewRunnableMethod(...)).
 //
 //   o  The WebKit API has redundant types for strings, and we should avoid
 //      using those beyond code that interfaces with the WebKit API.
 
 #ifndef CHROME_COMMON_WEBKIT_PARAM_TRAITS_H_
 #define CHROME_COMMON_WEBKIT_PARAM_TRAITS_H_
 #pragma once
 
 #include "ipc/ipc_message_utils.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebCache.h"
-#include "third_party/WebKit/WebKit/chromium/public/WebCompositionUnderline.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebConsoleMessage.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebContextMenuData.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebDragOperation.h"
-#include "third_party/WebKit/WebKit/chromium/public/WebFindOptions.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebInputEvent.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebMediaPlayerAction.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebPopupType.h"
-#include "third_party/WebKit/WebKit/chromium/public/WebScreenInfo.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebTextDirection.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebTextInputType.h"
 
+namespace WebKit {
+struct WebCompositionUnderline;
+struct WebFindOptions;
+struct WebRect;
+struct WebScreenInfo;
+}
+
 namespace IPC {
 
 template <>
 struct ParamTraits<WebKit::WebRect> {
   typedef WebKit::WebRect param_type;
-  static void Write(Message* m, const param_type& p) {
-    WriteParam(m, p.x);
-    WriteParam(m, p.y);
-    WriteParam(m, p.width);
-    WriteParam(m, p.height);
-  }
-  static bool Read(const Message* m, void** iter, param_type* p) {
-    return
-      ReadParam(m, iter, &p->x) &&
-      ReadParam(m, iter, &p->y) &&
-      ReadParam(m, iter, &p->width) &&
-      ReadParam(m, iter, &p->height);
-  }
-  static void Log(const param_type& p, std::wstring* l) {
-    l->append(L"(");
-    LogParam(p.x, l);
-    l->append(L", ");
-    LogParam(p.y, l);
-    l->append(L", ");
-    LogParam(p.width, l);
-    l->append(L", ");
-    LogParam(p.height, l);
-    l->append(L")");
-  }
+  static void Write(Message* m, const param_type& p);
+  static bool Read(const Message* m, void** iter, param_type* p);
+  static void Log(const param_type& p, std::wstring* l);
 };
 
 template <>
 struct ParamTraits<WebKit::WebScreenInfo> {
   typedef WebKit::WebScreenInfo param_type;
-  static void Write(Message* m, const param_type& p) {
-    WriteParam(m, p.depth);
-    WriteParam(m, p.depthPerComponent);
-    WriteParam(m, p.isMonochrome);
-    WriteParam(m, p.rect);
-    WriteParam(m, p.availableRect);
-  }
-  static bool Read(const Message* m, void** iter, param_type* p) {
-    return
-      ReadParam(m, iter, &p->depth) &&
-      ReadParam(m, iter, &p->depthPerComponent) &&
-      ReadParam(m, iter, &p->isMonochrome) &&
-      ReadParam(m, iter, &p->rect) &&
-      ReadParam(m, iter, &p->availableRect);
-  }
-  static void Log(const param_type& p, std::wstring* l) {
-    l->append(L"(");
-    LogParam(p.depth, l);
-    l->append(L", ");
-    LogParam(p.depthPerComponent, l);
-    l->append(L", ");
-    LogParam(p.isMonochrome, l);
-    l->append(L", ");
-    LogParam(p.rect, l);
-    l->append(L", ");
-    LogParam(p.availableRect, l);
-    l->append(L")");
-  }
+  static void Write(Message* m, const param_type& p);
+  static bool Read(const Message* m, void** iter, param_type* p);
+  static void Log(const param_type& p, std::wstring* l);
 };
 
 template <>
 struct ParamTraits<WebKit::WebConsoleMessage::Level> {
   typedef WebKit::WebConsoleMessage::Level param_type;
   static void Write(Message* m, const param_type& p) {
     WriteParam(m, static_cast<int>(p));
   }
   static bool Read(const Message* m, void** iter, param_type* r) {
     int value;
@@ skipping 21 matching lines @@
     return true;
   }
   static void Log(const param_type& p, std::wstring* l) {
     LogParam(static_cast<int>(p), l);
   }
 };
 
 template <>
 struct ParamTraits<WebKit::WebFindOptions> {
   typedef WebKit::WebFindOptions param_type;
-  static void Write(Message* m, const param_type& p) {
-    WriteParam(m, p.forward);
-    WriteParam(m, p.matchCase);
-    WriteParam(m, p.findNext);
-  }
-  static bool Read(const Message* m, void** iter, param_type* p) {
-    return
-      ReadParam(m, iter, &p->forward) &&
-      ReadParam(m, iter, &p->matchCase) &&
-      ReadParam(m, iter, &p->findNext);
-  }
-  static void Log(const param_type& p, std::wstring* l) {
-    l->append(L"(");
-    LogParam(p.forward, l);
-    l->append(L", ");
-    LogParam(p.matchCase, l);
-    l->append(L", ");
-    LogParam(p.findNext, l);
-    l->append(L")");
-  }
+  static void Write(Message* m, const param_type& p);
+  static bool Read(const Message* m, void** iter, param_type* p);
+  static void Log(const param_type& p, std::wstring* l);
 };
 
 template <>
 struct ParamTraits<WebKit::WebInputEvent::Type> {
   typedef WebKit::WebInputEvent::Type param_type;
   static void Write(Message* m, const param_type& p) {
     m->WriteInt(p);
   }
   static bool Read(const Message* m, void** iter, param_type* p) {
     int type;
@@ skipping 197 matching lines @@
     int temp;
     bool res = m->ReadInt(iter, &temp);
     *r = static_cast<param_type>(temp);
     return res;
   }
 };
 
 template <>
 struct ParamTraits<WebKit::WebCompositionUnderline> {
   typedef WebKit::WebCompositionUnderline param_type;
-  static void Write(Message* m, const param_type& p) {
-    WriteParam(m, p.startOffset);
-    WriteParam(m, p.endOffset);
-    WriteParam(m, p.color);
-    WriteParam(m, p.thick);
-  }
-  static bool Read(const Message* m, void** iter, param_type* p) {
-    return
-        ReadParam(m, iter, &p->startOffset) &&
-        ReadParam(m, iter, &p->endOffset) &&
-        ReadParam(m, iter, &p->color) &&
-        ReadParam(m, iter, &p->thick);
-  }
-  static void Log(const param_type& p, std::wstring* l) {
-    l->append(L"(");
-    LogParam(p.startOffset, l);
-    l->append(L",");
-    LogParam(p.endOffset, l);
-    l->append(L":");
-    LogParam(p.color, l);
-    l->append(L":");
-    LogParam(p.thick, l);
-    l->append(L")");
-  }
+  static void Write(Message* m, const param_type& p);
+  static bool Read(const Message* m, void** iter, param_type* p);
+  static void Log(const param_type& p, std::wstring* l);
 };
 
 template <>
 struct ParamTraits<WebKit::WebTextInputType> {
   typedef WebKit::WebTextInputType param_type;
   static void Write(Message* m, const param_type& p) {
     m->WriteInt(p);
   }
   static bool Read(const Message* m, void** iter, param_type* p) {
     int type;
@@ skipping 19 matching lines @@
         control = L"UNKNOWN";
         break;
     }
     LogParam(control, l);
   }
 };
 
 }  // namespace IPC
 
 #endif  // CHROME_COMMON_WEBKIT_PARAM_TRAITS_H_