[dart:io] Namespaces for file IO

runtime/bin/namespace.cc

+// Copyright (c) 2017, 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.
+
+#if !defined(DART_IO_DISABLED)
+
+#include "bin/namespace.h"
+
+#include "bin/builtin.h"
+#include "bin/dartutils.h"
+#include "include/dart_api.h"
+#include "platform/globals.h"
+
+namespace dart {
+namespace bin {
+
+static const int kNamespaceNativeFieldIndex = 0;
+
+static void ReleaseNamespace(void* isolate_callback_data,
+                             Dart_WeakPersistentHandle handle,
+                             void* peer) {
+  Namespace* namespc = reinterpret_cast<Namespace*>(peer);
+  ASSERT(namespc != NULL);
+  namespc->Release();
+}
+
+#if defined(DEBUG)
+static bool IsNamespace(Dart_Handle namespc_obj) {
+  Dart_Handle namespc_type =
+      DartUtils::GetDartType("dart:io", "_NamespaceImpl");
+  ASSERT(!Dart_IsError(namespc_type));
+  bool isinstance = false;
+  Dart_Handle result =
+      Dart_ObjectIsType(namespc_obj, namespc_type, &isinstance);
+  ASSERT(!Dart_IsError(result));
+  return isinstance;
+}
+#endif
+
+void FUNCTION_NAME(Namespace_Create)(Dart_NativeArguments args) {
+  Dart_Handle namespc_obj = Dart_GetNativeArgument(args, 0);
+  if (Dart_IsError(namespc_obj)) {
+    Dart_PropagateError(namespc_obj);
+  }
+  DEBUG_ASSERT(IsNamespace(namespc_obj));
+
+  // Allocate a native wrapper for the platform namespc bits.
+  Namespace* namespc = NULL;
+  Dart_Handle result;
+  Dart_Handle native_namespc = Dart_GetNativeArgument(args, 1);
+  if (Dart_IsInteger(native_namespc)) {
+    int64_t namespc_val;
+    result = Dart_IntegerToInt64(native_namespc, &namespc_val);
+    if (Dart_IsError(result)) {
+      Dart_PropagateError(result);
+    }
+    namespc = Namespace::Create(namespc_val);
+  } else if (Dart_IsString(native_namespc)) {
+    const char* namespc_path;
+    result = Dart_StringToCString(native_namespc, &namespc_path);
+    if (Dart_IsError(result)) {
+      Dart_PropagateError(result);
+    }
+    namespc = Namespace::Create(namespc_path);
+  } else {
+    // Propagate a type error.
+    Dart_ThrowException(
+        DartUtils::NewDartArgumentError("Argument must be an int or a String"));
+  }
+
+  // We were unable to create a native Namespace wrapper object due to some
+  // OS-level error.
+  if (namespc == NULL) {
+    Dart_SetReturnValue(args, DartUtils::NewDartOSError());
+  }
+
+  // Set the Dart objects native field to the native wrapper.
+  result = Dart_SetNativeInstanceField(namespc_obj, kNamespaceNativeFieldIndex,
+                                       reinterpret_cast<intptr_t>(namespc));
+  if (Dart_IsError(result)) {
+    namespc->Release();
+    Dart_PropagateError(result);
+  }
+
+  // Set up a finalizer for the Dart object so that we can do any necessary
+  // platform-specific cleanup for the namespc.
+  Dart_NewWeakPersistentHandle(namespc_obj, reinterpret_cast<void*>(namespc),
+                               sizeof(*namespc), ReleaseNamespace);
+  Dart_SetReturnValue(args, namespc_obj);
+}
+
+void FUNCTION_NAME(Namespace_GetDefault)(Dart_NativeArguments args) {
+  Dart_SetIntegerReturnValue(args, Namespace::Default());
+}
+
+void FUNCTION_NAME(Namespace_GetPointer)(Dart_NativeArguments args) {
+  Namespace* namespc = Namespace::GetNamespace(args, 0);
+  ASSERT(namespc != NULL);
+  namespc->Retain();
+  Dart_SetIntegerReturnValue(args, reinterpret_cast<intptr_t>(namespc));
+}
+
+Namespace* Namespace::GetNamespace(Dart_NativeArguments args, intptr_t index) {
+  Namespace* namespc;
+  Dart_Handle status =
+      Namespace::GetNativeNamespaceArgument(args, index, &namespc);
+  if (Dart_IsError(status)) {
+    Dart_PropagateError(status);
+  }
+  return namespc;
+}
+
+bool Namespace::IsDefault(Namespace* namespc) {
+  return (namespc == NULL) || (namespc->namespc() == Namespace::Default());
+}
+
+Dart_Handle Namespace::GetNativeNamespaceArgument(Dart_NativeArguments args,
+                                                  intptr_t index,
+                                                  Namespace** namespc) {
+  Dart_Handle namespc_obj = Dart_GetNativeArgument(args, index);
+  if (Dart_IsError(namespc_obj)) {
+    Dart_PropagateError(namespc_obj);
+  }
+  DEBUG_ASSERT(IsNamespace(namespc_obj));
+
+  Dart_Handle result =
+      Dart_GetNativeInstanceField(namespc_obj, kNamespaceNativeFieldIndex,
+                                  reinterpret_cast<intptr_t*>(namespc));
+  if (Dart_IsError(result)) {
+    return result;
+  }
+  return Dart_Null();
+}
+
+}  // namespace bin
+}  // namespace dart
+
+#endif  // !defined(DART_IO_DISABLED)