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/remote_util.h

@@ -0,0 +1,123 @@
+/*
+ * 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.
+ */
+
+#ifndef COMMON_REMOTE_UTIL_H_
+#define COMMON_REMOTE_UTIL_H_
+
+#include <string>
+#include <vector>
+
+#include "absl/status/status.h"
+#include "common/process.h"
+#include "common/sdk_util.h"
+
+namespace cdc_ft {
+
+// Utilities for executing remote commands on a gamelet through SSH.
+// Windows-only.
+class RemoteUtil {
+ public:
+  // If |verbosity| is > 0 and |quiet| is false, output from scp, ssh etc.
+  // commands is shown.
+  // If |quiet| is true, scp, ssh etc. commands use quiet mode.
+  // If |forward_output_to_log| is true, process output is forwarded to logging
+  // instead of this process's stdout/stderr.
+  RemoteUtil(int verbosity, bool quiet, ProcessFactory* process_factory,
+             bool forward_output_to_log);
+
+  // Returns the initialization status. Should be OK unless in case of some rare
+  // internal error. Should be checked before accessing any members.
+  const absl::Status& GetInitStatus() const {
+    return sdk_util_.GetInitStatus();
+  }
+
+  // Set IP of the remote instance and the ssh tunnel port.
+  void SetIpAndPort(const std::string& gamelet_ip, int ssh_port);
+
+  // Copies |source_filepaths| to the remote folder |dest| on the gamelet using
+  // scp. Must call either InitSsh or SetGameletIp before calling this method.
+  // If |compress| is true, compressed upload is used.
+  absl::Status Scp(std::vector<std::string> source_filepaths,
+                   const std::string& dest, bool compress);
+
+  // Syncs |source_filepaths| to the remote folder |dest| on the gamelet using
+  // cdc_rsync. Must call either InitSsh or SetGameletIp before calling this
+  // method.
+  absl::Status Sync(std::vector<std::string> source_filepaths,
+                    const std::string& dest);
+
+  // Calls 'chmod |mode| |remote_path|' on the gamelet.
+  // Must call either InitSsh or SetGameletIp before calling this method.
+  absl::Status Chmod(const std::string& mode, const std::string& remote_path,
+                     bool quiet = false);
+
+  // Calls 'rm [-f] |remote_path|' on the gamelet.
+  // Must call either InitSsh or SetGameletIp before calling this method.
+  absl::Status Rm(const std::string& remote_path, bool force);
+
+  // Calls `mv |old_remote_path| |new_remote_path| on the gamelet.
+  // Must call either InitSsh or SetGameletIp before calling this method.
+  absl::Status Mv(const std::string& old_remote_path,
+                  const std::string& new_remote_path);
+
+  // Runs |remote_command| on the gamelet. The command must be properly escaped.
+  // |name| is the name of the command displayed in the logs.
+  // Must call either InitSsh or SetGameletIp before calling this method.
+  absl::Status Run(std::string remote_command, std::string name);
+
+  // Builds an ssh command that executes |remote_command| on the gamelet.
+  ProcessStartInfo BuildProcessStartInfoForSsh(std::string remote_command);
+
+  // Builds an ssh command that runs SSH port forwarding to the gamelet, using
+  // the given |local_port| and |remote_port|.
+  // If |reverse| is true, sets up reverse port forwarding.
+  // Must call either InitSsh or SetGameletIp before calling this method.
+  ProcessStartInfo BuildProcessStartInfoForSshPortForward(int local_port,
+                                                          int remote_port,
+                                                          bool reverse);
+
+  // Builds an ssh command that executes |remote_command| on the gamelet, using
+  // port forwarding with given |local_port| and |remote_port|.
+  // If |reverse| is true, sets up reverse port forwarding.
+  // Must call either InitSsh or SetGameletIp before calling this method.
+  ProcessStartInfo BuildProcessStartInfoForSshPortForwardAndCommand(
+      int local_port, int remote_port, bool reverse,
+      std::string remote_command);
+
+  // Returns whether output is suppressed.
+  bool Quiet() const { return quiet_; }
+
+ private:
+  // Verifies that both |gamelet_ip_| and |ssh_port_| are set.
+  absl::Status CheckIpPort();
+
+  // Common code for BuildProcessStartInfoForSsh*.
+  ProcessStartInfo BuildProcessStartInfoForSshInternal(
+      std::string forward_arg, std::string remote_command);
+
+  const int verbosity_;
+  const bool quiet_;
+  ProcessFactory* const process_factory_;
+  const bool forward_output_to_log_;
+
+  SdkUtil sdk_util_;
+  std::string gamelet_ip_;
+  int ssh_port_ = 0;
+};
+
+}  // namespace cdc_ft
+
+#endif  // COMMON_REMOTE_UTIL_H_