Canonicalize uris in C++ instead of Dart for the standalone embedder.

runtime/vm/dart_api_impl.cc

 // Copyright (c) 2013, 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 "include/dart_mirrors_api.h"
 #include "include/dart_native_api.h"
 
 #include "platform/assert.h"
 #include "lib/stacktrace.h"
@@ skipping 24 matching lines @@
 #include "vm/service_event.h"
 #include "vm/service_isolate.h"
 #include "vm/service.h"
 #include "vm/stack_frame.h"
 #include "vm/symbols.h"
 #include "vm/tags.h"
 #include "vm/thread_registry.h"
 #include "vm/timeline.h"
 #include "vm/timer.h"
 #include "vm/unicode.h"
+#include "vm/uri.h"
 #include "vm/verifier.h"
 #include "vm/version.h"
 
 namespace dart {
 
 // Facilitate quick access to the current zone once we have the curren thread.
 #define Z (T->zone())
 
 
 DECLARE_FLAG(bool, print_class_table);
@@ skipping 5086 matching lines @@
 
 DART_EXPORT Dart_Handle Dart_SetLibraryTagHandler(
     Dart_LibraryTagHandler handler) {
   Isolate* isolate = Isolate::Current();
   CHECK_ISOLATE(isolate);
   isolate->set_library_tag_handler(handler);
   return Api::Success();
 }
 
 
+DART_EXPORT Dart_Handle Dart_DefaultCanonicalizeUrl(Dart_Handle library,
+                                                    Dart_Handle url) {
+  API_TIMELINE_DURATION;
+  DARTSCOPE(Thread::Current());
+  CHECK_CALLBACK_STATE(T);
+
+  const Library& lib = Api::UnwrapLibraryHandle(Z, library);
+  if (lib.IsNull()) {
+    RETURN_TYPE_ERROR(Z, library, Library);
+  }
+  const String& uri = Api::UnwrapStringHandle(Z, url);
+  if (uri.IsNull()) {
+    RETURN_TYPE_ERROR(Z, url, String);
+  }
+
+  const String& lib_uri = String::Handle(Z, lib.url());
+  const char* resolved_uri;

[ahe, 2016/05/25 12:44:52]

I don't understand how memory is managed for this.

[Florian Schneider, 2016/05/26 14:09:45]

The string is in zone-allocated memory.

+  if (!ResolveUri(uri.ToCString(), lib_uri.ToCString(), &resolved_uri)) {
+    return Api::NewError("%s: Unable to canonicalize uri '%s'.",
+                         CURRENT_FUNC, uri.ToCString());
+  }
+  return Api::NewHandle(T, String::New(resolved_uri));
+}
+
+
 // NOTE: Need to pass 'result' as a parameter here in order to avoid
 // warning: variable 'result' might be clobbered by 'longjmp' or 'vfork'
 // which shows up because of the use of setjmp.
 static void CompileSource(Thread* thread,
                           const Library& lib,
                           const Script& script,
                           Dart_Handle* result) {
   bool update_lib_status = (script.kind() == RawScript::kScriptTag ||
                             script.kind() == RawScript::kLibraryTag);
   if (update_lib_status) {
@@ skipping 1215 matching lines @@
 
 DART_EXPORT bool Dart_IsPrecompiledRuntime() {
 #if defined(DART_PRECOMPILED_RUNTIME)
   return true;
 #else
   return false;
 #endif
 }
 
 }  // namespace dart