Introduce kPerIsolateDataIndex and tidy JS_Define.h

fpdfsdk/src/jsapi/fxjs_v8.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "../../../core/include/fxcrt/fx_basic.h"
-#include "../../include/fsdk_define.h"
 #include "../../include/jsapi/fxjs_v8.h"
 
 const wchar_t kFXJSValueNameString[] = L"string";
 const wchar_t kFXJSValueNameNumber[] = L"number";
 const wchar_t kFXJSValueNameBoolean[] = L"boolean";
 const wchar_t kFXJSValueNameDate[] = L"date";
 const wchar_t kFXJSValueNameObject[] = L"object";
 const wchar_t kFXJSValueNameFxobj[] = L"fxobj";
 const wchar_t kFXJSValueNameNull[] = L"null";
 const wchar_t kFXJSValueNameUndefined[] = L"undefined";
 
 static unsigned int g_embedderDataSlot = 1u;
 
+// Keep this consistent with the values defined in gin/public/context_holder.h
+// (without actually requiring a dependency on gin itself for the standalone
+// embedders of PDFIum). The value we want to use is:
+//   kPerContextDataStartIndex + kEmbedderPDFium, which is 3.
+static const unsigned int kPerContextDataIndex = 3u;
+
 class CFXJS_PrivateData {
  public:
   CFXJS_PrivateData(int nObjDefID) : ObjDefID(nObjDefID), pPrivate(NULL) {}
 
   int ObjDefID;
   void* pPrivate;
 };
 
 class CFXJS_ObjDefinition {
  public:
@@ skipping 61 matching lines @@
   if (!pIsolate->GetData(g_embedderDataSlot))
     pIsolate->SetData(g_embedderDataSlot, new FXJS_PerIsolateData());
 }
 
 // static
 FXJS_PerIsolateData* FXJS_PerIsolateData::Get(v8::Isolate* pIsolate) {
   return static_cast<FXJS_PerIsolateData*>(
       pIsolate->GetData(g_embedderDataSlot));
 }
 
+void FXJS_Initialize(unsigned int embedderDataSlot) {
+  g_embedderDataSlot = embedderDataSlot;
+}
+
+void FXJS_Release() {
+}
+
 int FXJS_DefineObj(v8::Isolate* pIsolate,
                    const wchar_t* sObjName,
                    FXJSOBJTYPE eObjType,
                    FXJS_CONSTRUCTOR pConstructor,
                    FXJS_DESTRUCTOR pDestructor) {
   v8::Isolate::Scope isolate_scope(pIsolate);
   v8::HandleScope handle_scope(pIsolate);
 
   FXJS_PerIsolateData::SetUp(pIsolate);
   FXJS_PerIsolateData* pData = FXJS_PerIsolateData::Get(pIsolate);
@@ skipping 148 matching lines @@
   v8::HandleScope handle_scope(pIsolate);
 
   v8::Global<v8::ObjectTemplate>& globalObjTemp =
       _getGlobalObjectTemplate(pIsolate);
   v8::Local<v8::Context> v8Context = v8::Context::New(
       pIsolate, NULL,
       v8::Local<v8::ObjectTemplate>::New(pIsolate, globalObjTemp));
   v8::Context::Scope context_scope(v8Context);
 
   FXJS_PerIsolateData::SetUp(pIsolate);
   v8::Local<v8::External> ptr = v8::External::New(pIsolate, pFXRuntime);

[Tom Sepez, 2015/09/25 17:32:18]

Here's the spot where I'd like to use the AlignedPointer methods, but I'm not
sure how to go about this.  Do I need an ordinary v8::Object here that would
hold it in a slot?  Would this object still be set in the context's
kPerContextDataIndex slot?

A code fragment might be illuminating.

[jochen (gone - plz use gerrit), 2015/09/28 11:27:31]

v8Context->SetAlignedPointerInEmbedderData(kPerContextDataIndex, pFXRuntime);
should do the trick

[Tom Sepez, 2015/09/28 16:20:18]

Done. Appears to work (I thought I'd tried this earlier but got segvs, which is
why I asked).

-  v8Context->SetEmbedderData(1, ptr);
+  v8Context->SetEmbedderData(kPerContextDataIndex, ptr);
 
   int maxID = CFXJS_ObjDefinition::MaxID(pIsolate);
   for (int i = 0; i < maxID; ++i) {
     CFXJS_ObjDefinition* pObjDef = CFXJS_ObjDefinition::ForID(pIsolate, i);
     CFX_WideString ws = CFX_WideString(pObjDef->objName);
     CFX_ByteString bs = ws.UTF8Encode();
     v8::Local<v8::String> objName =
         v8::String::NewFromUtf8(pIsolate, bs.c_str(),
                                 v8::NewStringType::kNormal,
                                 bs.GetLength()).ToLocalChecked();
@@ skipping 48 matching lines @@
         pObjDef->m_pDestructor(pObj);
       FXJS_FreePrivate(pObj);
     }
     delete pObjDef;
   }
 
   pIsolate->SetData(g_embedderDataSlot, nullptr);
   delete pData;
 }
 
-void FXJS_Initialize(unsigned int embedderDataSlot) {
-  g_embedderDataSlot = embedderDataSlot;
-}
-
-void FXJS_Release() {
+IFXJS_Runtime* FXJS_GetRuntimeFromIsolate(v8::Isolate* pIsolate) {
+  v8::Local<v8::Context> context = pIsolate->GetCurrentContext();
+  v8::Local<v8::Value> v = context->GetEmbedderData(kPerContextDataIndex);
+  if (v.IsEmpty())
+    return nullptr;
+  v8::Local<v8::External> field = v8::Local<v8::External>::Cast(v);
+  return static_cast<IFXJS_Runtime*>(field->Value());
 }
 
 int FXJS_Execute(v8::Isolate* pIsolate,
                  IFXJS_Context* pJSContext,
                  const wchar_t* script,
                  long length,
                  FXJSErr* pError) {
   v8::Isolate::Scope isolate_scope(pIsolate);
   v8::TryCatch try_catch(pIsolate);
 
@@ skipping 402 matching lines @@
     return v8::Local<v8::Array>();
   v8::Local<v8::Context> context = pIsolate->GetCurrentContext();
   return v8::Local<v8::Array>::Cast(pValue->ToObject(context).ToLocalChecked());
 }
 
 void FXJS_ValueCopy(v8::Local<v8::Value>& pTo, v8::Local<v8::Value> pFrom) {
   pTo = pFrom;
 }