Dart: Adds a program to create snapshots of Mojo apps.

mojo/dart/dart_snapshotter/main.cc

+// Copyright 2015 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 <iostream>
+
+#include "base/at_exit.h"
+#include "base/basictypes.h"
+#include "base/command_line.h"
+#include "base/files/file_path.h"
+#include "base/files/file_util.h"
+#include "base/logging.h"
+#include "base/process/memory.h"
+#include "dart/runtime/include/dart_api.h"
+#include "mojo/dart/dart_snapshotter/loader.h"
+#include "mojo/dart/dart_snapshotter/vm.h"
+#include "tonic/dart_error.h"
+#include "tonic/dart_isolate_scope.h"
+
+const char kHelp[] = "help";
+const char kPackageRoot[] = "package-root";
+const char kSnapshot[] = "snapshot";
+
+void Usage() {
+  std::cerr << "Usage: dart_snapshotter"
+            << " --" << kPackageRoot << " --" << kSnapshot
+            << " <dart-app>" << std::endl;
+}
+
+void WriteSnapshot(base::FilePath path) {
+  uint8_t* buffer;
+  intptr_t size;
+  CHECK(!tonic::LogIfError(Dart_CreateScriptSnapshot(&buffer, &size)));
+
+  CHECK_EQ(base::WriteFile(path, reinterpret_cast<const char*>(buffer), size),
+           size);
+}
+
+int main(int argc, const char* argv[]) {
+  base::AtExitManager exit_manager;
+  base::EnableTerminationOnHeapCorruption();
+  base::CommandLine::Init(argc, argv);
+
+  const base::CommandLine& command_line =
+      *base::CommandLine::ForCurrentProcess();
+
+  if (command_line.HasSwitch(kHelp) || command_line.GetArgs().empty()) {
+    Usage();
+    return 0;
+  }
+
+  InitDartVM();
+
+  CHECK(command_line.HasSwitch(kPackageRoot)) << "Need --package-root";
+  InitLoader(command_line.GetSwitchValuePath(kPackageRoot));
+
+  Dart_Isolate isolate = CreateDartIsolate();
+  CHECK(isolate);
+
+  tonic::DartIsolateScope scope(isolate);
+  tonic::DartApiScope api_scope;
+
+  auto args = command_line.GetArgs();
+  CHECK(args.size() == 1);
+  LoadScript(args[0]);
+
+  CHECK(!tonic::LogIfError(Dart_FinalizeLoading(true)));
+
+  CHECK(command_line.HasSwitch(kSnapshot)) << "Need --snapshot";
+  WriteSnapshot(command_line.GetSwitchValuePath(kSnapshot));
+
+  return 0;
+}