Add a safe API for creating ASCII-only strings

src/api.cc

 // Copyright 2012 the V8 project authors. 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
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 4831 matching lines @@
   if (length == 0) return Empty();
   ENTER_V8(isolate);
   if (length == -1) length = i::StrLength(data);
   i::Handle<i::String> result =
       isolate->factory()->NewStringFromUtf8(
           i::Vector<const char>(data, length));
   return Utils::ToLocal(result);
 }
 
 
+Local<String> v8::String::NewFromAscii(const char* data, int length) {
+  i::Isolate* isolate = i::Isolate::Current();
+  EnsureInitializedForIsolate(isolate, "v8::String::NewFromAscii()");
+  LOG_API(isolate, "String::NewFromAscii(char)");
+  if (length == 0) return Empty();
+  ENTER_V8(isolate);
+  if (length == -1) length = i::StrLength(data);
+  i::Handle<i::String> result =
+      isolate->factory()->NewStringFromAsciiSafe(
+          i::Vector<const char>(data, length));
+  return Utils::ToLocal(result);
+}
+
+
 Local<String> v8::String::Concat(Handle<String> left, Handle<String> right) {
   i::Handle<i::String> left_string = Utils::OpenHandle(*left);
   i::Isolate* isolate = left_string->GetIsolate();
   EnsureInitializedForIsolate(isolate, "v8::String::New()");
   LOG_API(isolate, "String::New(char)");
   ENTER_V8(isolate);
   i::Handle<i::String> right_string = Utils::OpenHandle(*right);
   i::Handle<i::String> result = isolate->factory()->NewConsString(left_string,
                                                                   right_string);
   return Utils::ToLocal(result);
@@ skipping 1849 matching lines @@
 
   v->VisitPointers(blocks_.first(), first_block_limit_);
 
   for (int i = 1; i < blocks_.length(); i++) {
     v->VisitPointers(blocks_[i], &blocks_[i][kHandleBlockSize]);
   }
 }
 
 
 } }  // namespace v8::internal