Implement external strings.

runtime/vm/dart_api_impl.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "include/dart_api.h"
 
 #include "vm/bigint_operations.h"
 #include "vm/class_finalizer.h"
 #include "vm/compiler.h"
 #include "vm/dart.h"
@@ skipping 705 matching lines @@
   HandleScope scope;  // Setup a VM handle scope.
   const String& obj = String::Handle(String::New(codepoints, length));
   return Api::NewLocalHandle(obj);
 }
 
 
 DART_EXPORT Dart_Handle Dart_NewString32(const uint32_t* codepoints,
                                          intptr_t length) {
   Zone zone;  // Setup a VM zone as we are creating some handles.
   HandleScope scope;  // Setup a VM handle scope.
-  UNIMPLEMENTED();
   const String& obj = String::Handle(String::New(codepoints, length));
   return Api::NewLocalHandle(obj);
 }
 
 
+DART_EXPORT Dart_Handle Dart_NewExternalString8(
+    uint8_t* codepoints,
+    intptr_t length,
+    Dart_ExternalString8Finalizer finalizer) {
+  Zone zone;  // Setup a VM zone as we are creating some handles.
+  HandleScope scope;  // Setup a VM handle scope.
+  const String& obj =
+      String::Handle(
+          ExternalOneByteString::New(codepoints, length, finalizer));
+  return Api::NewLocalHandle(obj);
+}
+
+
+DART_EXPORT Dart_Handle Dart_NewExternalString16(
+    uint16_t* codepoints,
+    intptr_t length,
+    Dart_ExternalString16Finalizer finalizer) {
+  Zone zone;  // Setup a VM zone as we are creating some handles.
+  HandleScope scope;  // Setup a VM handle scope.
+  const String& obj =
+        String::Handle(
+          ExternalTwoByteString::New(codepoints, length, finalizer));
+  return Api::NewLocalHandle(obj);
+}
+
+
+DART_EXPORT Dart_Handle Dart_NewExternalString32(
+    uint32_t* codepoints,
+    intptr_t length,
+    Dart_ExternalString32Finalizer finalizer) {
+  Zone zone;  // Setup a VM zone as we are creating some handles.
+  HandleScope scope;  // Setup a VM handle scope.
+  const String& obj =
+      String::Handle(
+          ExternalFourByteString::New(codepoints, length, finalizer));
+  return Api::NewLocalHandle(obj);
+}
+
+
 DART_EXPORT bool Dart_IsString8(Dart_Handle object) {
   Zone zone;  // Setup a VM zone as we are creating some handles.
   HandleScope scope;  // Setup a VM handle scope.
   const Object& obj = Object::Handle(Api::UnwrapHandle(object));
-  return obj.IsOneByteString();
+  return obj.IsOneByteString() || obj.IsExternalOneByteString();
 }
 
 
 DART_EXPORT bool Dart_IsString16(Dart_Handle object) {
   Zone zone;  // Setup a VM zone as we are creating some handles.
   HandleScope scope;  // Setup a VM handle scope.
   const Object& obj = Object::Handle(Api::UnwrapHandle(object));
-  return obj.IsOneByteString() || obj.IsTwoByteString();
+  return (obj.IsOneByteString() || obj.IsExternalOneByteString() ||
+          obj.IsTwoByteString() || obj.IsExternalOneByteString());
 }
 
 
 DART_EXPORT Dart_Result Dart_StringGet8(Dart_Handle str,
                                         uint8_t* codepoints,
                                         intptr_t length) {

[turnidge, 2011/10/25 18:07:20]

You have updated the Dart_isString* functions but not the Dart_StringGet*
functions.  Is that intentional?

[cshapiro, 2011/10/25 20:42:47]

Nope, that was an oversight..

   Zone zone;  // Setup a VM zone as we are creating some handles.
   HandleScope scope;  // Setup a VM handle scope.
   const Object& obj = Object::Handle(Api::UnwrapHandle(str));
   if (obj.IsOneByteString()) {
     OneByteString& string_obj = OneByteString::Handle();
     string_obj ^= obj.raw();
     intptr_t str_len = string_obj.Length();
     intptr_t copy_len = (str_len > length) ? length : str_len;
     for (intptr_t i = 0; i < copy_len; i++) {
       codepoints[i] = static_cast<uint8_t>(string_obj.CharAt(i));
@@ skipping 960 matching lines @@
   ASSERT(isolate != NULL);
   ApiState* state = isolate->api_state();
   ASSERT(state != NULL);
   ApiLocalScope* scope = state->top_scope();
   ASSERT(scope != NULL);
   return scope->zone().Reallocate(ptr, old_size, new_size);
 }
 
 
 }  // namespace dart