Add exists, create and delete to directory implementation on Linux and Mac.

runtime/bin/directory.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 "bin/dartutils.h"
 #include "bin/directory.h"
 
 #include "include/dart_api.h"
 
 static intptr_t GetHandlerPort(Dart_Handle handle) {
   if (Dart_IsNull(handle)) {
-    // TODO(ager): Generalize this to Directory::kInvalidId.
     return 0;
   }
   return DartUtils::GetIntegerInstanceField(handle, DartUtils::kIdFieldName);
 }
 
 
 void FUNCTION_NAME(Directory_List)(Dart_NativeArguments args) {
   Dart_EnterScope();
   Dart_Handle path = Dart_GetNativeArgument(args, 1);
   bool recursive = DartUtils::GetBooleanValue(Dart_GetNativeArgument(args, 2));
   Dart_Port dir_port = GetHandlerPort(Dart_GetNativeArgument(args, 3));
   Dart_Port file_port = GetHandlerPort(Dart_GetNativeArgument(args, 4));
   Dart_Port done_port = GetHandlerPort(Dart_GetNativeArgument(args, 5));
   Dart_Port error_port =
       GetHandlerPort(Dart_GetNativeArgument(args, 6));
   ASSERT(Dart_IsString(path));
   Directory::List(DartUtils::GetStringValue(path),
                   recursive,
                   dir_port,
                   file_port,
                   done_port,
                   error_port);
   Dart_ExitScope();
 }
+
+
+void FUNCTION_NAME(Directory_Exists)(Dart_NativeArguments args) {
+  Dart_EnterScope();
+  Dart_Handle path = Dart_GetNativeArgument(args, 1);
+  ASSERT(Dart_IsString(path));
+  Directory::ExistsResult result =
+      Directory::Exists(DartUtils::GetStringValue(path));
+  int return_value = -1;
+  if (result == Directory::EXISTS) {
+    return_value = 1;
+  }
+  if (result == Directory::DOES_NOT_EXIST) {
+    return_value = 0;
+  }
+  Dart_SetReturnValue(args, Dart_NewInteger(return_value));
+  Dart_ExitScope();
+}
+
+
+void FUNCTION_NAME(Directory_Create)(Dart_NativeArguments args) {
+  Dart_EnterScope();
+  Dart_Handle path = Dart_GetNativeArgument(args, 1);
+  ASSERT(Dart_IsString(path));
+  bool created = Directory::Create(DartUtils::GetStringValue(path));
+  Dart_SetReturnValue(args, Dart_NewBoolean(created));
+  Dart_ExitScope();
+}
+
+
+void FUNCTION_NAME(Directory_Delete)(Dart_NativeArguments args) {
+  Dart_EnterScope();
+  Dart_Handle path = Dart_GetNativeArgument(args, 1);
+  ASSERT(Dart_IsString(path));
+  bool deleted = Directory::Delete(DartUtils::GetStringValue(path));
+  Dart_SetReturnValue(args, Dart_NewBoolean(deleted));
+  Dart_ExitScope();
+}