[wasm] Allow Uint8Array in _WASMEXP_.instantiateModule()

src/wasm/wasm-js.cc

 // Copyright 2015 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/api.h"
 #include "src/api-natives.h"
 #include "src/assert-scope.h"
 #include "src/ast/ast.h"
 #include "src/ast/scopes.h"
 #include "src/factory.h"
@@ skipping 19 matching lines @@
 namespace {
 struct RawBuffer {
   const byte* start;
   const byte* end;
   size_t size() { return static_cast<size_t>(end - start); }
 };
 
 
 RawBuffer GetRawBufferArgument(
     ErrorThrower& thrower, const v8::FunctionCallbackInfo<v8::Value>& args) {
-  // TODO(titzer): allow typed array views.
-  if (args.Length() < 1 || !args[0]->IsArrayBuffer()) {
+  if (args.Length() < 1) {
     thrower.Error("Argument 0 must be an array buffer");
     return {nullptr, nullptr};
   }
-  Local<ArrayBuffer> buffer = Local<ArrayBuffer>::Cast(args[0]);
-  ArrayBuffer::Contents contents = buffer->GetContents();
 
-  const byte* start = reinterpret_cast<const byte*>(contents.Data());
-  const byte* end = start + contents.ByteLength();
+  const byte* start = nullptr;
+  const byte* end = nullptr;
 
-  if (start == nullptr) {
-    thrower.Error("ArrayBuffer argument is empty");
+  if (args[0]->IsArrayBuffer()) {
+    // A raw array buffer was passed.
+    Local<ArrayBuffer> buffer = Local<ArrayBuffer>::Cast(args[0]);
+    ArrayBuffer::Contents contents = buffer->GetContents();
+
+    start = reinterpret_cast<const byte*>(contents.Data());
+    end = start + contents.ByteLength();
+
+    if (start == nullptr) {

[Derek Schuff, 2016/03/07 20:37:17]

should we also throw if the length is 0 or otherwise bad?
edit: we do below, might as well here too?

[titzer, 2016/03/07 20:39:53]

Done.

+      thrower.Error("ArrayBuffer argument is empty");
+    }
+  } else if (args[0]->IsUint8Array()) {
+    // A Uint8Array was passed.
+    Local<Uint8Array> array = Local<Uint8Array>::Cast(args[0]);
+    Local<ArrayBuffer> buffer = array->Buffer();
+
+    ArrayBuffer::Contents contents = buffer->GetContents();
+
+    start =
+        reinterpret_cast<const byte*>(contents.Data()) + array->ByteOffset();
+    end = start + array->ByteLength();
+
+    if (start == nullptr || end == start) {
+      thrower.Error("ArrayBuffer argument is empty");
+    }
+  } else {
+    thrower.Error("Argument 0 must be an ArrayBuffer or Uint8Array");
   }
+
   return {start, end};
 }
 
 
 void VerifyModule(const v8::FunctionCallbackInfo<v8::Value>& args) {
   HandleScope scope(args.GetIsolate());
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(args.GetIsolate());
   ErrorThrower thrower(isolate, "WASM.verifyModule()");
 
   RawBuffer buffer = GetRawBufferArgument(thrower, args);
@@ skipping 222 matching lines @@
   if (!context->get(Context::WASM_FUNCTION_MAP_INDEX)->IsMap()) {
     Handle<Map> wasm_function_map = isolate->factory()->NewMap(
         JS_FUNCTION_TYPE, JSFunction::kSize + kPointerSize);
     wasm_function_map->set_is_callable();
     context->set_wasm_function_map(*wasm_function_map);
   }
 }
 
 }  // namespace internal
 }  // namespace v8