Initial work on Dart bindings for Mojo.

mojo/dart/system/mojo_dart_embedder.cc

Index: mojo/dart/system/mojo_dart_embedder.cc
diff --git a/mojo/dart/system/mojo_dart_embedder.cc b/mojo/dart/system/mojo_dart_embedder.cc
new file mode 100644
index 0000000000000000000000000000000000000000..8c95fa0188305218d90a8af457985dc0eb82c96b
--- /dev/null
+++ b/mojo/dart/system/mojo_dart_embedder.cc
@@ -0,0 +1,133 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <string.h>
+
+#include "base/memory/scoped_ptr.h"
+
+#include "dart_api.h"
+
+#include "mojo/edk/embedder/embedder.h"
+#include "mojo/edk/embedder/platform_support.h"
+#include "mojo/edk/embedder/simple_platform_support.h"
+#include "mojo/public/platform/native/system_thunks.h"
+
+
+#define HELPER_FUNCTIONS(V)                                                    \
+  V(MojoEmbedder_Init)                                                         \
+  V(MojoSystemThunks_Make)                                                     \
+
+static Dart_NativeFunction ResolveName(
+    Dart_Handle name, int argc, bool* auto_setup_scope);
+
+
+DART_EXPORT Dart_Handle mojo_dart_embedder_Init(Dart_Handle parent_library) {
+  if (Dart_IsError(parent_library)) {
+    return parent_library;
+  }
+
+  Dart_Handle result_code = Dart_SetNativeResolver(
+      parent_library, ResolveName, NULL);
+  if (Dart_IsError(result_code)) {
+    return result_code;
+  }
+
+  return Dart_Null();
+}
+
+
+static Dart_Handle HandleError(Dart_Handle handle) {
+  if (Dart_IsError(handle)) {
+    Dart_PropagateError(handle);
+  }
+  return handle;
+}
+
+
+static void MojoEmbedder_Init(Dart_NativeArguments arguments) {
+  Dart_EnterScope();
+
+  mojo::embedder::Init(scoped_ptr<mojo::embedder::PlatformSupport>(
+      new mojo::embedder::SimplePlatformSupport()));
+
+  Dart_SetReturnValue(arguments, Dart_Null());
+  Dart_ExitScope();
+}
+
+
+static void MojoSystemThunks_Make(Dart_NativeArguments arguments) {
+  Dart_EnterScope();
+
+  Dart_Handle closure = HandleError(Dart_GetNativeArgument(arguments, 0));
+  if (Dart_IsClosure(closure)) {
+    MojoSystemThunks thunks = MojoMakeSystemThunks();
+    int64_t thunks_addr = reinterpret_cast<int64_t>(&thunks);
+
+    Dart_Handle t = Dart_NewInteger(thunks_addr);
+    Dart_InvokeClosure(closure, 1, &t);
+  }
+
+  Dart_SetReturnValue(arguments, Dart_Null());
+  Dart_ExitScope();
+}
+
+
+struct FunctionLookup {
+  const char* name;
+  Dart_NativeFunction function;
+};
+
+
+#define FUNCTION_STRING_MAP(name) {#name, name},
+
+FunctionLookup function_list[] = {
+    HELPER_FUNCTIONS(FUNCTION_STRING_MAP)
+    {NULL, NULL}};
+
+#undef FUNCTION_STRING_MAP
+
+
+FunctionLookup no_scope_function_list[] = {
+  {NULL, NULL}
+};
+
+Dart_NativeFunction ResolveName(Dart_Handle name,
+                                int argc,
+                                bool* auto_setup_scope) {
+  if (!Dart_IsString(name)) {
+    return NULL;
+  }
+  Dart_NativeFunction result = NULL;
+  if (auto_setup_scope == NULL) {
+    return NULL;
+  }
+
+  Dart_EnterScope();
+  const char* cname;
+  HandleError(Dart_StringToCString(name, &cname));
+
+  for (int i=0; function_list[i].name != NULL; ++i) {
+    if (strcmp(function_list[i].name, cname) == 0) {
+      *auto_setup_scope = true;
+      result = function_list[i].function;
+      break;
+    }
+  }
+
+  if (result != NULL) {
+    Dart_ExitScope();
+    return result;
+  }
+
+  for (int i=0; no_scope_function_list[i].name != NULL; ++i) {
+    if (strcmp(no_scope_function_list[i].name, cname) == 0) {
+      *auto_setup_scope = false;
+      result = no_scope_function_list[i].function;
+      break;
+    }
+  }
+
+  Dart_ExitScope();
+  return result;
+}