Pass v8::Isolate to PDFium at init time.

Move the external isolate and embedder slot from the
IPDF_JSPlatforms struct supplied at the
FPDFDOC_InitFormFillEnvironment() call time to arguments to
the FPDF_InitLibraryWithConfig() call.

This has several benefits:
-- Avoids the crash that could happen if multiple
FPDFDOC_InitFormFillEnvironmen() calls should happen to be
made by an embedder with different slot values.
-- Down the road, for XFA, there may be XFA but no FormFill
environment.

We support both forms for the time being, until the chrome
side catches up, at which point we will deprecate the old
way.

R=thestig@chromium.org

Review URL: https://codereview.chromium.org/1367033002 .

4 files changed, 46 insertions, 26 deletions

diff --git a/fpdfsdk/src/fpdfview.cpp b/fpdfsdk/src/fpdfview.cpp
index 3603af6d91..0bf6426b66 100644
--- a/fpdfsdk/src/fpdfview.cpp
+++ b/fpdfsdk/src/fpdfview.cpp
@@ -14,6 +14,7 @@
 #include "../include/fsdk_define.h"
 #include "../include/fsdk_mgr.h"
 #include "../include/fsdk_rendercontext.h"
+#include "../include/jsapi/fxjs_v8.h"
 
 CPDF_CustomAccess::CPDF_CustomAccess(FPDF_FILEACCESS* pFileAccess) {
   if (pFileAccess)
@@ -109,6 +110,10 @@ DLLEXPORT void STDCALL FPDF_InitLibraryWithConfig(
     pModuleMgr->LoadEmbeddedCNS1CMaps();
     pModuleMgr->LoadEmbeddedKorea1CMaps();
   }
+  if (cfg && cfg->version >= 2) {
+    FXJS_Initialize(cfg->m_v8EmbedderSlot,
+                    reinterpret_cast<v8::Isolate*>(cfg->m_pIsolate));
+  }
 }
 
 DLLEXPORT void STDCALL FPDF_DestroyLibrary() {
diff --git a/fpdfsdk/src/javascript/JS_Runtime.cpp b/fpdfsdk/src/javascript/JS_Runtime.cpp
index 1e1486df5c..5c463ce498 100644
--- a/fpdfsdk/src/javascript/JS_Runtime.cpp
+++ b/fpdfsdk/src/javascript/JS_Runtime.cpp
@@ -35,22 +35,17 @@ CJS_Runtime::CJS_Runtime(CPDFDoc_Environment* pApp)
       m_bBlocking(FALSE),
       m_isolate(NULL),
       m_isolateManaged(false) {
-  unsigned int embedderDataSlot = 0;
-  if (m_pApp->GetFormFillInfo()->m_pJsPlatform->version >= 2) {
-    m_isolate = reinterpret_cast<v8::Isolate*>(
-        m_pApp->GetFormFillInfo()->m_pJsPlatform->m_isolate);
-    embedderDataSlot = pApp->GetFormFillInfo()->m_pJsPlatform->m_v8EmbedderSlot;
-  }
-  if (!m_isolate) {
-    m_pArrayBufferAllocator.reset(new FXJS_ArrayBufferAllocator());
-
-    v8::Isolate::CreateParams params;
-    params.array_buffer_allocator = m_pArrayBufferAllocator.get();
-    m_isolate = v8::Isolate::New(params);
-    m_isolateManaged = true;
+  IPDF_JSPLATFORM* pPlatform = m_pApp->GetFormFillInfo()->m_pJsPlatform;
+  if (pPlatform->version <= 2) {
+    unsigned int embedderDataSlot = 0;
+    v8::Isolate* pExternalIsolate = nullptr;
+    if (pPlatform->version == 2) {
+      pExternalIsolate = reinterpret_cast<v8::Isolate*>(pPlatform->m_isolate);
+      embedderDataSlot = pPlatform->m_v8EmbedderSlot;
+    }
+    FXJS_Initialize(embedderDataSlot, pExternalIsolate);
   }
-
-  FXJS_Initialize(embedderDataSlot);
+  m_isolateManaged = FXJS_GetIsolate(&m_isolate);
   DefineJSObjects();
 
   CJS_Context* pContext = (CJS_Context*)NewContext();
diff --git a/fpdfsdk/src/jsapi/fxjs_v8.cpp b/fpdfsdk/src/jsapi/fxjs_v8.cpp
index 667132fde4..ff45a7a0ce 100644
--- a/fpdfsdk/src/jsapi/fxjs_v8.cpp
+++ b/fpdfsdk/src/jsapi/fxjs_v8.cpp
@@ -16,14 +16,14 @@ 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;
-
+static unsigned int g_embedderDataSlot = 1u;
+static v8::Isolate* g_isolate = nullptr;
+static FXJS_ArrayBufferAllocator* g_arrayBufferAllocator = nullptr;
 static v8::Global<v8::ObjectTemplate>* g_DefaultGlobalObjectTemplate = nullptr;
 
 class CFXJS_PrivateData {
@@ -131,6 +131,33 @@ void FXJS_ArrayBufferAllocator::Free(void* data, size_t length) {
   free(data);
 }
 
+void FXJS_Initialize(unsigned int embedderDataSlot, v8::Isolate* pIsolate) {
+  g_embedderDataSlot = embedderDataSlot;
+  g_isolate = pIsolate;
+}
+
+void FXJS_Release() {
+  g_DefaultGlobalObjectTemplate = nullptr;
+  g_isolate = nullptr;
+
+  delete g_arrayBufferAllocator;
+  g_arrayBufferAllocator = nullptr;
+}
+
+bool FXJS_GetIsolate(v8::Isolate** pResultIsolate) {
+  if (g_isolate) {
+    *pResultIsolate = g_isolate;
+    return false;
+  }
+  // Provide backwards compatibility when no external isolate.
+  if (!g_arrayBufferAllocator)
+    g_arrayBufferAllocator = new FXJS_ArrayBufferAllocator();
+  v8::Isolate::CreateParams params;
+  params.array_buffer_allocator = g_arrayBufferAllocator;
+  *pResultIsolate = v8::Isolate::New(params);
+  return true;
+}
+
 // static
 void FXJS_PerIsolateData::SetUp(v8::Isolate* pIsolate) {
   if (!pIsolate->GetData(g_embedderDataSlot))
@@ -143,13 +170,6 @@ FXJS_PerIsolateData* FXJS_PerIsolateData::Get(v8::Isolate* pIsolate) {
       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,
diff --git a/fpdfsdk/src/jsapi/fxjs_v8_embeddertest.cpp b/fpdfsdk/src/jsapi/fxjs_v8_embeddertest.cpp
index 7726c40c5e..1c660397d1 100644
--- a/fpdfsdk/src/jsapi/fxjs_v8_embeddertest.cpp
+++ b/fpdfsdk/src/jsapi/fxjs_v8_embeddertest.cpp
@@ -30,7 +30,7 @@ class FXJSV8Embeddertest : public EmbedderTest {
 
     v8::Isolate::Scope isolate_scope(m_pIsolate);
     v8::HandleScope handle_scope(m_pIsolate);
-    FXJS_Initialize(0);
+    FXJS_Initialize(0, nullptr);
     FXJS_PerIsolateData::SetUp(m_pIsolate);
     FXJS_InitializeRuntime(m_pIsolate, nullptr, nullptr, m_pPersistentContext);
   }