// Copyright 2010 the V8 project 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 "src/extensions/externalize-string-extension.h" #include "include/v8-template.h" #include "src/api/api-inl.h" #include "src/base/strings.h" #include "src/execution/isolate.h" #include "src/handles/handles.h" #include "src/objects/objects-inl.h" namespace v8 { namespace internal { template <typename Char, typename Base> class SimpleStringResource : public Base { public: // Takes ownership of |data|. SimpleStringResource(Char* data, size_t length) : data_(data), length_(length) {} ~SimpleStringResource() override { delete[] data_; } const Char* data() const override { return data_; } size_t length() const override { return length_; } private: Char* const data_; const size_t length_; }; using SimpleOneByteStringResource = SimpleStringResource<char, v8::String::ExternalOneByteStringResource>; using SimpleTwoByteStringResource = SimpleStringResource<base::uc16, v8::String::ExternalStringResource>; const char* const ExternalizeStringExtension::kSource = "native function externalizeString();" "native function isOneByteString();" "function x() { return 1; }"; v8::Local<v8::FunctionTemplate> ExternalizeStringExtension::GetNativeFunctionTemplate( v8::Isolate* isolate, v8::Local<v8::String> str) { if (strcmp(*v8::String::Utf8Value(isolate, str), "externalizeString") == 0) { return v8::FunctionTemplate::New(isolate, ExternalizeStringExtension::Externalize); } else { DCHECK_EQ(strcmp(*v8::String::Utf8Value(isolate, str), "isOneByteString"), 0); return v8::FunctionTemplate::New(isolate, ExternalizeStringExtension::IsOneByte); } } void ExternalizeStringExtension::Externalize( const v8::FunctionCallbackInfo<v8::Value>& args) { if (args.Length() < 1 || !args[0]->IsString()) { args.GetIsolate()->ThrowError( "First parameter to externalizeString() must be a string."); return; } bool force_two_byte = false; if (args.Length() >= 2) { if (args[1]->IsBoolean()) { force_two_byte = args[1]->BooleanValue(args.GetIsolate()); } else { args.GetIsolate()->ThrowError( "Second parameter to externalizeString() must be a boolean."); return; } } bool result = false; Handle<String> string = Utils::OpenHandle(*args[0].As<v8::String>()); if (!string->SupportsExternalization()) { args.GetIsolate()->ThrowError("string does not support externalization."); return; } if (string->IsOneByteRepresentation() && !force_two_byte) { uint8_t* data = new uint8_t[string->length()]; String::WriteToFlat(*string, data, 0, string->length()); SimpleOneByteStringResource* resource = new SimpleOneByteStringResource( reinterpret_cast<char*>(data), string->length()); result = Utils::ToLocal(string)->MakeExternal(resource); if (!result) delete resource; } else { base::uc16* data = new base::uc16[string->length()]; String::WriteToFlat(*string, data, 0, string->length()); SimpleTwoByteStringResource* resource = new SimpleTwoByteStringResource( data, string->length()); result = Utils::ToLocal(string)->MakeExternal(resource); if (!result) delete resource; } if (!result) { args.GetIsolate()->ThrowError("externalizeString() failed."); return; } } void ExternalizeStringExtension::IsOneByte( const v8::FunctionCallbackInfo<v8::Value>& args) { if (args.Length() != 1 || !args[0]->IsString()) { args.GetIsolate()->ThrowError( "isOneByteString() requires a single string argument."); return; } bool is_one_byte = Utils::OpenHandle(*args[0].As<v8::String>())->IsOneByteRepresentation(); args.GetReturnValue().Set(is_one_byte); } } // namespace internal } // namespace v8