Releasing the former Stadia file transfer tools

The tools allow efficient and fast synchronization of large directory
trees from a Windows workstation to a Linux target machine.

cdc_rsync* support efficient copy of files by using content-defined
chunking (CDC) to identify chunks within files that can be reused.

asset_stream_manager + cdc_fuse_fs support efficient streaming of a
local directory to a remote virtual file system based on FUSE. It also
employs CDC to identify and reuse unchanged data chunks.

common/sdk_util.cc

@@ -0,0 +1,93 @@
+// Copyright 2022 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "common/sdk_util.h"
+
+#include <cassert>
+#include <string>
+
+#include "common/clock.h"
+#include "common/path.h"
+#include "common/status_macros.h"
+
+namespace cdc_ft {
+
+SdkUtil::SdkUtil() {
+  init_status_ = path::GetKnownFolderPath(path::FolderId::kRoamingAppData,
+                                          &roaming_appdata_path_);
+  init_status_.Update(path::GetKnownFolderPath(path::FolderId::kProgramFiles,
+                                               &program_files_path_));
+  absl::Status status = path::GetEnv("GGP_SDK_PATH", &ggp_sdk_path_env_);
+  if (absl::IsNotFound(status) || ggp_sdk_path_env_.empty())
+    ggp_sdk_path_env_ = path::Join(program_files_path_, "GGP SDK");
+
+  // Create an empty config file if it does not exist yet.
+  const std::string ssh_config_path = GetSshConfigPath();
+  if (!path::Exists(ssh_config_path)) {
+    init_status_.Update(path::CreateDirRec(path::DirName(ssh_config_path)));
+    init_status_.Update(path::WriteFile(ssh_config_path, nullptr, 0));
+  }
+}
+
+SdkUtil::~SdkUtil() = default;
+
+std::string SdkUtil::GetUserConfigPath() const {
+  assert(init_status_.ok());
+  return path::Join(roaming_appdata_path_, "GGP");
+}
+
+std::string SdkUtil::GetServicesConfigPath() const {
+  return path::Join(GetUserConfigPath(), "services");
+}
+
+std::string SdkUtil::GetLogPath(const char* log_base_name) const {
+  DefaultSystemClock clock;
+  std::string timestamp_ext = clock.FormatNow(".%Y%m%d-%H%M%S.log", false);
+  return path::Join(GetUserConfigPath(), "logs", log_base_name + timestamp_ext);
+}
+
+std::string SdkUtil::GetSshConfigPath() const {
+  return path::Join(GetUserConfigPath(), "ssh", "config");
+}
+
+std::string SdkUtil::GetSshKeyFilePath() const {
+  return path::Join(GetUserConfigPath(), "ssh", "id_rsa");
+}
+
+std::string SdkUtil::GetSshKnownHostsFilePath() const {
+  return path::Join(GetUserConfigPath(), "ssh", "known_hosts");
+}
+
+std::string SdkUtil::GetSDKPath() const {
+  assert(init_status_.ok());
+  return ggp_sdk_path_env_;
+}
+
+std::string SdkUtil::GetDevBinPath() const {
+  return path::Join(GetSDKPath(), "dev", "bin");
+}
+
+std::string SdkUtil::GetSshPath() const {
+  return path::Join(GetSDKPath(), "tools", "OpenSSH-Win64");
+}
+
+std::string SdkUtil::GetSshExePath() const {
+  return path::Join(GetSshPath(), "ssh.exe");
+}
+
+std::string SdkUtil::GetScpExePath() const {
+  return path::Join(GetSshPath(), "scp.exe");
+}
+
+}  // namespace cdc_ft