Fix for issue 23598, add a Dart_CreateLibrarySnapshot entrypoint to the API.

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 "vm/class_finalizer.h"
@@ skipping 1457 matching lines @@
   FullSnapshotWriter writer(vm_isolate_snapshot_buffer,
                             isolate_snapshot_buffer,
                             ApiReallocate);
   writer.WriteFullSnapshot();
   *vm_isolate_snapshot_size = writer.VmIsolateSnapshotSize();
   *isolate_snapshot_size = writer.IsolateSnapshotSize();
   return Api::Success();
 }
 
 
-DART_EXPORT Dart_Handle Dart_CreateScriptSnapshot(uint8_t** buffer,
-                                                  intptr_t* size) {
+static Dart_Handle createLibrarySnapshot(Dart_Handle library,
+                                         uint8_t** buffer,
+                                         intptr_t* size) {
   Isolate* isolate = Isolate::Current();
   DARTSCOPE(isolate);
   TIMERSCOPE(isolate, time_creating_snapshot);
   if (buffer == NULL) {
     RETURN_NULL_ERROR(buffer);
   }
   if (size == NULL) {
     RETURN_NULL_ERROR(size);
   }
   // Finalize all classes if needed.
   Dart_Handle state = Api::CheckAndFinalizePendingClasses(isolate);
   if (::Dart_IsError(state)) {
     return state;
   }
-  Library& library =
-      Library::Handle(isolate, isolate->object_store()->root_library());
-  if (library.IsNull()) {
-    return
-        Api::NewError("%s expects the isolate to have a script loaded in it.",
-                      CURRENT_FUNC);
+  Library& lib = Library::Handle(isolate);
+  if (library == Dart_Null()) {
+    lib ^= isolate->object_store()->root_library();
+  } else {
+    lib ^= Api::UnwrapHandle(library);
   }
   ScriptSnapshotWriter writer(buffer, ApiReallocate);
-  writer.WriteScriptSnapshot(library);
+  writer.WriteScriptSnapshot(lib);
   *size = writer.BytesWritten();
   return Api::Success();
 }
 
 
+DART_EXPORT Dart_Handle Dart_CreateScriptSnapshot(uint8_t** buffer,
+                                                  intptr_t* size) {
+  return createLibrarySnapshot(Dart_Null(), buffer, size);
+}
+
+
+DART_EXPORT Dart_Handle Dart_CreateLibrarySnapshot(Dart_Handle library,
+                                                   uint8_t** buffer,
+                                                   intptr_t* size) {
+  return createLibrarySnapshot(library, buffer, size);
+}
+
+
 DART_EXPORT void Dart_InterruptIsolate(Dart_Isolate isolate) {
   TRACE_API_CALL(CURRENT_FUNC);
   if (isolate == NULL) {
     FATAL1("%s expects argument 'isolate' to be non-null.",  CURRENT_FUNC);
   }
   // TODO(16615): Validate isolate parameter.
   Isolate* iso = reinterpret_cast<Isolate*>(isolate);
   iso->ScheduleInterrupts(Isolate::kApiInterrupt);
   // Can't use Dart_Post() since there isn't a current isolate.
   Dart_CObject api_null = { Dart_CObject_kNull , { 0 } };
@@ skipping 4075 matching lines @@
 
 
 DART_EXPORT void Dart_RegisterRootServiceRequestCallback(
     const char* name,
     Dart_ServiceRequestCallback callback,
     void* user_data) {
   Service::RegisterRootEmbedderCallback(name, callback, user_data);
 }
 
 }  // namespace dart