********** WebCore blob hacking

WebCore/bindings/v8/SerializedScriptValue.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 413 matching lines @@
         doWriteWebCoreString(type);
     }
 
     void writeFileList(const FileList& fileList)
     {
         append(FileListTag);
         uint32_t length = fileList.length();
         doWriteUint32(length);
         for (unsigned i = 0; i < length; ++i) {
             doWriteWebCoreString(fileList.item(i)->path());
-            doWriteWebCoreString(fileList.item(i)->url().string());
+            doWriteWebCoreString(fileList.item(i)->uuid()); // TODO: bump version numbers somewhere?
             doWriteWebCoreString(fileList.item(i)->type());
         }
     }
 
     void writeArrayBuffer(const ArrayBuffer& arrayBuffer)
     {
         append(ArrayBufferTag);
         doWriteArrayBuffer(arrayBuffer);
     }
 
@@ skipping 252 matching lines @@
 public:
     enum Status {
         Success,
         InputError,
         DataCloneError,
         InvalidStateError,
         JSException,
         JSFailure
     };
 
-    Serializer(Writer& writer, MessagePortArray* messagePorts, ArrayBufferArray* arrayBuffers, Vector<String>& blobURLs, v8::TryCatch& tryCatch)
+    Serializer(Writer& writer, MessagePortArray* messagePorts, ArrayBufferArray* arrayBuffers, BlobDataHandleMap& blobDataHandles, v8::TryCatch& tryCatch)
         : m_writer(writer)
         , m_tryCatch(tryCatch)
         , m_depth(0)
         , m_execDepth(0)
         , m_status(Success)
         , m_nextObjectReference(0)
-        , m_blobURLs(blobURLs)
+        , m_blobDataHandles(blobDataHandles)
     {
         ASSERT(!tryCatch.HasCaught());
         if (messagePorts) {
             for (size_t i = 0; i < messagePorts->size(); i++)
                 m_transferredMessagePorts.set(toV8Object(messagePorts->at(i).get(), m_writer.getIsolate()), i);
         }
         if (arrayBuffers) {
             for (size_t i = 0; i < arrayBuffers->size(); i++)  {
                 v8::Handle<v8::Object> v8ArrayBuffer = toV8Object(arrayBuffers->at(i).get(), m_writer.getIsolate());
                 // Coalesce multiple occurences of the same buffer to the first index.
@@ skipping 346 matching lines @@
     {
         v8::Handle<v8::BooleanObject> booleanObject = value.As<v8::BooleanObject>();
         m_writer.writeBooleanObject(booleanObject->BooleanValue());
     }
 
     void writeBlob(v8::Handle<v8::Value> value)
     {
         Blob* blob = V8Blob::toNative(value.As<v8::Object>());
         if (!blob)
             return;
-        m_writer.writeBlob(blob->url().string(), blob->type(), blob->size());
-        m_blobURLs.append(blob->url().string());
+        m_writer.writeBlob(blob->uuid(), blob->type(), blob->size());
+        m_blobDataHandles.add(blob->uuid(), blob->blobDataHandle());
     }
 
 #if ENABLE(FILE_SYSTEM)
     StateBase* writeDOMFileSystem(v8::Handle<v8::Value> value, StateBase* next)
     {
         DOMFileSystem* fs = V8DOMFileSystem::toNative(value.As<v8::Object>());
         if (!fs)
             return 0;
         if (!fs->clonable())
             return handleError(DataCloneError, next);
         m_writer.writeDOMFileSystem(fs->type(), fs->name(), fs->rootURL().string());
         return 0;
     }
 #endif
 
     void writeFile(v8::Handle<v8::Value> value)
     {
         File* file = V8File::toNative(value.As<v8::Object>());
         if (!file)
             return;
-        m_writer.writeFile(file->path(), file->url().string(), file->type());
-        m_blobURLs.append(file->url().string());
+        m_writer.writeFile(file->path(), file->uuid(), file->type());
+        m_blobDataHandles.add(file->uuid(), file->blobDataHandle());
     }
 
     void writeFileList(v8::Handle<v8::Value> value)
     {
         FileList* fileList = V8FileList::toNative(value.As<v8::Object>());
         if (!fileList)
             return;
         m_writer.writeFileList(*fileList);
         unsigned length = fileList->length();
         for (unsigned i = 0; i < length; ++i)
-            m_blobURLs.append(fileList->item(i)->url().string());
+            m_blobDataHandles.add(fileList->item(i)->uuid(), fileList->item(i)->blobDataHandle());
     }
 
     void writeImageData(v8::Handle<v8::Value> value)
     {
         ImageData* imageData = V8ImageData::toNative(value.As<v8::Object>());
         if (!imageData)
             return;
         Uint8ClampedArray* pixelArray = imageData->data();
         m_writer.writeImageData(imageData->width(), imageData->height(), pixelArray->data(), pixelArray->length());
     }
@@ skipping 98 matching lines @@
     Writer& m_writer;
     v8::TryCatch& m_tryCatch;
     int m_depth;
     int m_execDepth;
     Status m_status;
     typedef V8ObjectMap<v8::Object, uint32_t> ObjectPool;
     ObjectPool m_objectPool;
     ObjectPool m_transferredMessagePorts;
     ObjectPool m_transferredArrayBuffers;
     uint32_t m_nextObjectReference;
-    Vector<String>& m_blobURLs;
+    BlobDataHandleMap& m_blobDataHandles;
 };
 
 Serializer::StateBase* Serializer::doSerialize(v8::Handle<v8::Value> value, StateBase* next)
 {
     if (m_execDepth + (next ? next->execDepth() : 0) > 1) {
         m_writer.writeNull();
         return 0;
     }
     m_writer.writeReferenceCount(m_nextObjectReference);
     uint32_t objectReference;
@@ skipping 89 matching lines @@
     virtual bool newObject() = 0;
     virtual bool completeObject(uint32_t numProperties, v8::Handle<v8::Value>*) = 0;
     virtual bool completeSparseArray(uint32_t numProperties, uint32_t length, v8::Handle<v8::Value>*) = 0;
     virtual bool completeDenseArray(uint32_t numProperties, uint32_t length, v8::Handle<v8::Value>*) = 0;
 };
 
 // Reader is responsible for deserializing primitive types and
 // restoring information about saved objects of composite types.
 class Reader {
 public:
-    Reader(const uint8_t* buffer, int length, v8::Isolate* isolate)
+    Reader(const uint8_t* buffer, int length, v8::Isolate* isolate, const BlobDataHandleMap& blobDataHandles)
         : m_buffer(buffer)
         , m_length(length)
         , m_position(0)
         , m_version(0)
         , m_isolate(isolate)
+        , m_blobDataHandles(blobDataHandles)
     {
         ASSERT(!(reinterpret_cast<size_t>(buffer) & 1));
         ASSERT(length >= 0);
     }
 
     bool isEof() const { return m_position >= m_length; }
 
     bool read(v8::Handle<v8::Value>* value, CompositeCreator& creator)
     {
         SerializationTag tag;
@@ skipping 492 matching lines @@
             return false;
         uint32_t flags;
         if (!doReadUint32(&flags))
             return false;
         *value = v8::RegExp::New(pattern.As<v8::String>(), static_cast<v8::RegExp::Flags>(flags));
         return true;
     }
 
     bool readBlob(v8::Handle<v8::Value>* value)
     {
-        String url;
+        String uuid;
         String type;
         uint64_t size;
-        if (!readWebCoreString(&url))
+        if (!readWebCoreString(&uuid))
             return false;
         if (!readWebCoreString(&type))
             return false;
         if (!doReadUint64(&size))
             return false;
-        PassRefPtr<Blob> blob = Blob::create(KURL(ParsedURLString, url), type, size);
+        PassRefPtr<Blob> blob = Blob::create(getOrCreateBlobDataHandle(uuid, type, size));
         *value = toV8(blob, v8::Handle<v8::Object>(), m_isolate);
         return true;
     }
 
 #if ENABLE(FILE_SYSTEM)
     bool readDOMFileSystem(v8::Handle<v8::Value>* value)
     {
         uint32_t type;
         String name;
         String url;
         if (!doReadUint32(&type))
             return false;
         if (!readWebCoreString(&name))
             return false;
         if (!readWebCoreString(&url))
             return false;
         RefPtr<DOMFileSystem> fs = DOMFileSystem::create(getScriptExecutionContext(), name, static_cast<WebCore::FileSystemType>(type), KURL(ParsedURLString, url), AsyncFileSystem::create());
         *value = toV8(fs.release(), v8::Handle<v8::Object>(), m_isolate);
         return true;
     }
 #endif
 
     bool readFile(v8::Handle<v8::Value>* value)
     {
         String path;
-        String url;
+        String uuid;
         String type;
         if (!readWebCoreString(&path))
             return false;
-        if (!readWebCoreString(&url))
+        if (!readWebCoreString(&uuid))
             return false;
         if (!readWebCoreString(&type))
             return false;
-        PassRefPtr<File> file = File::create(path, KURL(ParsedURLString, url), type);
+        PassRefPtr<File> file = File::create(path, getOrCreateBlobDataHandle(uuid, type));
         *value = toV8(file, v8::Handle<v8::Object>(), m_isolate);
         return true;
     }
 
     bool readFileList(v8::Handle<v8::Value>* value)
     {
         uint32_t length;
         if (!doReadUint32(&length))
             return false;
         PassRefPtr<FileList> fileList = FileList::create();
         for (unsigned i = 0; i < length; ++i) {
             String path;
-            String urlString;
+            String uuid;
             String type;
             if (!readWebCoreString(&path))
                 return false;
-            if (!readWebCoreString(&urlString))
+            if (!readWebCoreString(&uuid))
                 return false;
             if (!readWebCoreString(&type))
                 return false;
-            fileList->append(File::create(path, KURL(ParsedURLString, urlString), type));
+            fileList->append(File::create(path, getOrCreateBlobDataHandle(uuid, type)));
         }
         *value = toV8(fileList, v8::Handle<v8::Object>(), m_isolate);
         return true;
     }
 
     template<class T>
     bool doReadUintHelper(T* value)
     {
         *value = 0;
         uint8_t currentByte;
@@ skipping 21 matching lines @@
     bool doReadNumber(double* number)
     {
         if (m_position + sizeof(double) > m_length)
             return false;
         uint8_t* numberAsByteArray = reinterpret_cast<uint8_t*>(number);
         for (unsigned i = 0; i < sizeof(double); ++i)
             numberAsByteArray[i] = m_buffer[m_position++];
         return true;
     }
 
+    PassRefPtr<BlobDataHandle> getOrCreateBlobDataHandle(const String& uuid, const String& type, long long size = -1)
+    {
+        // The containing ssv may have a BDH for this uuid if this ssv is just being
+        // passed from main to worker thread (for example). We use those values when creating the 
+        // new blob instead of cons'ing up a new BDH.
+        //
+        // FIXME: Maybe we should require that it work that way where the ssv must have a BDH for any
+        // blobs it comes across during deserialization. Would require callers to explicitly populate
+        // the collection of BDH's for blobs to work, which would encourage lifetimes to be considered
+        // when passing ssv's around cross process. At present, we get 'lucky' in some cases because
+        // the blob in the src process happens to still exists at the time the dest process is deserializing.
+        // For example in sharedWorker.postMesssage(...).
+        BlobDataHandleMap::const_iterator it = m_blobDataHandles.find(uuid);
+        if (it != m_blobDataHandles.end())
+            return it->value;
+        return BlobDataHandle::create(uuid, type, size);
+    }
+
     const uint8_t* m_buffer;
     const unsigned m_length;
     unsigned m_position;
     uint32_t m_version;
     v8::Isolate* m_isolate;
+    const BlobDataHandleMap& m_blobDataHandles;
 };
 
 
 typedef Vector<WTF::ArrayBufferContents, 1> ArrayBufferContentsArray;
 
 class Deserializer : public CompositeCreator {
 public:
     explicit Deserializer(Reader& reader, 
                           MessagePortArray* messagePorts, ArrayBufferContentsArray* arrayBufferContents)
         : m_reader(reader)
@@ skipping 433 matching lines @@
 }
 
 SerializedScriptValue::SerializedScriptValue(v8::Handle<v8::Value> value, MessagePortArray* messagePorts, ArrayBufferArray* arrayBuffers, bool& didThrow, v8::Isolate* isolate)
     : m_externallyAllocatedMemory(0)
 {
     didThrow = false;
     Writer writer(isolate);
     Serializer::Status status;
     {
         v8::TryCatch tryCatch;
-        Serializer serializer(writer, messagePorts, arrayBuffers, m_blobURLs, tryCatch);
+        Serializer serializer(writer, messagePorts, arrayBuffers, m_blobDataHandles, tryCatch);
         status = serializer.serialize(value);
         if (status == Serializer::JSException) {
             // If there was a JS exception thrown, re-throw it.
             didThrow = true;
             tryCatch.ReThrow();
             return;
         }
     }
     switch (status) {
     case Serializer::InputError:
@@ skipping 34 matching lines @@
 v8::Handle<v8::Value> SerializedScriptValue::deserialize(MessagePortArray* messagePorts)
 {
     return deserialize(v8::Isolate::GetCurrent(), messagePorts);
 }
 
 v8::Handle<v8::Value> SerializedScriptValue::deserialize(v8::Isolate* isolate, MessagePortArray* messagePorts)
 {
     if (!m_data.impl())
         return v8NullWithCheck(isolate);
     COMPILE_ASSERT(sizeof(BufferValueType) == 2, BufferValueTypeIsTwoBytes);
-    Reader reader(reinterpret_cast<const uint8_t*>(m_data.impl()->characters()), 2 * m_data.length(), isolate);
+    Reader reader(reinterpret_cast<const uint8_t*>(m_data.impl()->characters()), 2 * m_data.length(), isolate, m_blobDataHandles);
     Deserializer deserializer(reader, messagePorts, m_arrayBufferContentsArray.get());
     return deserializer.deserialize();
 }
 
 #if ENABLE(INSPECTOR)
 ScriptValue SerializedScriptValue::deserializeForInspector(ScriptState* scriptState)
 {
     v8::HandleScope handleScope;
     v8::Context::Scope contextScope(scriptState->context());
 
@@ skipping 19 matching lines @@
         v8::V8::AdjustAmountOfExternalAllocatedMemory(-m_externallyAllocatedMemory);
     }
 }
 
 uint32_t SerializedScriptValue::wireFormatVersion()
 {
     return WebCore::wireFormatVersion;
 }
 
 } // namespace WebCore