Assign external sizes to external strings and to external typed data created by the VM.

runtime/vm/dart_api_impl.cc

Index: runtime/vm/dart_api_impl.cc
diff --git a/runtime/vm/dart_api_impl.cc b/runtime/vm/dart_api_impl.cc
index 560b600dc8dcebc0570052d82638731441aed301..ccda7f0d172d6666140b1b55016e06ce5106d367 100644
--- a/runtime/vm/dart_api_impl.cc
+++ b/runtime/vm/dart_api_impl.cc
@@ -2557,7 +2557,7 @@ DART_EXPORT Dart_Handle Dart_StringStorageSize(Dart_Handle str,
 
 DART_EXPORT Dart_Handle Dart_MakeExternalString(Dart_Handle str,
                                                 void* array,
-                                                intptr_t length,
+                                                intptr_t external_size,
                                                 void* peer,
                                                 Dart_PeerFinalizer cback) {
   DARTSCOPE(Thread::Current());
@@ -2576,9 +2576,9 @@ DART_EXPORT Dart_Handle Dart_MakeExternalString(Dart_Handle str,
     RETURN_NULL_ERROR(array);
   }
   intptr_t str_size = (str_obj.Length() * str_obj.CharSize());
-  if ((length < str_size) || (length > String::kMaxElements)) {
+  if ((external_size < str_size) || (external_size > String::kMaxElements)) {
     return Api::NewError("Dart_MakeExternalString "
-                         "expects argument length to be in the range"
+                         "expects argument external_size to be in the range"
                          "[%" Pd "..%" Pd "].",
                          str_size, String::kMaxElements);
   }
@@ -2590,24 +2590,25 @@ DART_EXPORT Dart_Handle Dart_MakeExternalString(Dart_Handle str,
     // the peer from the Peer table.
     intptr_t copy_len = str_obj.Length();
     if (str_obj.IsOneByteString()) {
-      ASSERT(length >= copy_len);
+      ASSERT(external_size >= copy_len);
       uint8_t* latin1_array = reinterpret_cast<uint8_t*>(array);
       for (intptr_t i = 0; i < copy_len; i++) {
         latin1_array[i] = static_cast<uint8_t>(str_obj.CharAt(i));
       }
-      OneByteString::SetPeer(str_obj, peer, cback);
+      OneByteString::SetPeer(str_obj, external_size, peer, cback);
     } else {
       ASSERT(str_obj.IsTwoByteString());
-      ASSERT(length >= (copy_len * str_obj.CharSize()));
+      ASSERT(external_size >= (copy_len * str_obj.CharSize()));
       uint16_t* utf16_array = reinterpret_cast<uint16_t*>(array);
       for (intptr_t i = 0; i < copy_len; i++) {
         utf16_array[i] = str_obj.CharAt(i);
       }
-      TwoByteString::SetPeer(str_obj, peer, cback);
+      TwoByteString::SetPeer(str_obj, external_size, peer, cback);
     }
     return str;
   }
-  return Api::NewHandle(T, str_obj.MakeExternal(array, length, peer, cback));
+  return Api::NewHandle(T, str_obj.MakeExternal(array, external_size,
+                                                peer, cback));
 }