Refactor the daemon controller so that the callbacks are called on the caller thread.

remoting/host/setup/daemon_controller_linux.cc

Index: remoting/host/setup/daemon_controller_linux.cc
diff --git a/remoting/host/setup/daemon_controller_linux.cc b/remoting/host/setup/daemon_controller_linux.cc
deleted file mode 100644
index 3d4588599c582f06f1352689da8d428262d05f2b..0000000000000000000000000000000000000000
--- a/remoting/host/setup/daemon_controller_linux.cc
+++ /dev/null
@@ -1,371 +0,0 @@
-// Copyright (c) 2012 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 "remoting/host/setup/daemon_controller.h"
-
-#include <unistd.h>
-
-#include "base/basictypes.h"
-#include "base/bind.h"
-#include "base/command_line.h"
-#include "base/compiler_specific.h"
-#include "base/environment.h"
-#include "base/file_util.h"
-#include "base/files/file_path.h"
-#include "base/json/json_writer.h"
-#include "base/logging.h"
-#include "base/md5.h"
-#include "base/process/kill.h"
-#include "base/process/launch.h"
-#include "base/process/process_handle.h"
-#include "base/strings/string_number_conversions.h"
-#include "base/strings/string_split.h"
-#include "base/strings/string_util.h"
-#include "base/threading/thread.h"
-#include "base/values.h"
-#include "net/base/net_util.h"
-#include "remoting/host/host_config.h"
-#include "remoting/host/json_host_config.h"
-#include "remoting/host/usage_stats_consent.h"
-
-namespace remoting {
-
-namespace {
-
-const char kDaemonScript[] =
-    "/opt/google/chrome-remote-desktop/chrome-remote-desktop";
-
-// Timeout for running daemon script. The script itself sets a timeout when
-// waiting for the host to come online, so the setting here should be at least
-// as long.
-const int64 kDaemonTimeoutMs = 60000;
-
-// Timeout for commands that require password prompt - 5 minutes.
-const int64 kSudoTimeoutSeconds = 5 * 60;
-
-std::string GetMd5(const std::string& value) {
-  base::MD5Context ctx;
-  base::MD5Init(&ctx);
-  base::MD5Update(&ctx, value);
-  base::MD5Digest digest;
-  base::MD5Final(&digest, &ctx);
-  return StringToLowerASCII(base::HexEncode(digest.a, sizeof(digest.a)));
-}
-
-class DaemonControllerLinux : public remoting::DaemonController {
- public:
-  DaemonControllerLinux();
-
-  virtual State GetState() OVERRIDE;
-  virtual void GetConfig(const GetConfigCallback& callback) OVERRIDE;
-  virtual void SetConfigAndStart(
-      scoped_ptr<base::DictionaryValue> config,
-      bool consent,
-      const CompletionCallback& done) OVERRIDE;
-  virtual void UpdateConfig(scoped_ptr<base::DictionaryValue> config,
-                            const CompletionCallback& done_callback) OVERRIDE;
-  virtual void Stop(const CompletionCallback& done_callback) OVERRIDE;
-  virtual void SetWindow(void* window_handle) OVERRIDE;
-  virtual void GetVersion(const GetVersionCallback& done_callback) OVERRIDE;
-  virtual void GetUsageStatsConsent(
-      const GetUsageStatsConsentCallback& done) OVERRIDE;
-
- private:
-  base::FilePath GetConfigPath();
-
-  void DoGetConfig(const GetConfigCallback& callback);
-  void DoSetConfigAndStart(scoped_ptr<base::DictionaryValue> config,
-                           const CompletionCallback& done);
-  void DoUpdateConfig(scoped_ptr<base::DictionaryValue> config,
-                      const CompletionCallback& done_callback);
-  void DoStop(const CompletionCallback& done_callback);
-  void DoGetVersion(const GetVersionCallback& done_callback);
-
-  base::Thread file_io_thread_;
-
-  DISALLOW_COPY_AND_ASSIGN(DaemonControllerLinux);
-};
-
-DaemonControllerLinux::DaemonControllerLinux()
-    : file_io_thread_("DaemonControllerFileIO") {
-  file_io_thread_.Start();
-}
-
-static bool GetScriptPath(base::FilePath* result) {
-  base::FilePath candidate_exe(kDaemonScript);
-  if (access(candidate_exe.value().c_str(), X_OK) == 0) {
-    *result = candidate_exe;
-    return true;
-  }
-  return false;
-}
-
-static bool RunHostScriptWithTimeout(
-    const std::vector<std::string>& args,
-    base::TimeDelta timeout,
-    int* exit_code) {
-  DCHECK(exit_code);
-
-  // As long as we're relying on running an external binary from the
-  // PATH, don't do it as root.
-  if (getuid() == 0) {
-    LOG(ERROR) << "Refusing to run script as root.";
-    return false;
-  }
-  base::FilePath script_path;
-  if (!GetScriptPath(&script_path)) {
-    LOG(ERROR) << "GetScriptPath() failed.";
-    return false;
-  }
-  CommandLine command_line(script_path);
-  for (unsigned int i = 0; i < args.size(); ++i) {
-    command_line.AppendArg(args[i]);
-  }
-  base::ProcessHandle process_handle;
-
-  // Redirect the child's stdout to the parent's stderr. In the case where this
-  // parent process is a Native Messaging host, its stdout is used to send
-  // messages to the web-app.
-  base::FileHandleMappingVector fds_to_remap;
-  fds_to_remap.push_back(std::pair<int, int>(STDERR_FILENO, STDOUT_FILENO));
-  base::LaunchOptions options;
-  options.fds_to_remap = &fds_to_remap;
-  if (!base::LaunchProcess(command_line, options, &process_handle)) {
-    LOG(ERROR) << "Failed to run command: "
-               << command_line.GetCommandLineString();
-    return false;
-  }
-
-  if (!base::WaitForExitCodeWithTimeout(process_handle, exit_code, timeout)) {
-    base::KillProcess(process_handle, 0, false);
-    LOG(ERROR) << "Timeout exceeded for command: "
-               << command_line.GetCommandLineString();
-    return false;
-  }
-
-  return true;
-}
-
-static bool RunHostScript(const std::vector<std::string>& args,
-                          int* exit_code) {
-  return RunHostScriptWithTimeout(
-      args, base::TimeDelta::FromMilliseconds(kDaemonTimeoutMs), exit_code);
-}
-
-remoting::DaemonController::State DaemonControllerLinux::GetState() {
-  std::vector<std::string> args;
-  args.push_back("--check-running");
-  int exit_code = 0;
-  if (!RunHostScript(args, &exit_code)) {
-    // TODO(jamiewalch): When we have a good story for installing, return
-    // NOT_INSTALLED rather than NOT_IMPLEMENTED (the former suppresses
-    // the relevant UI in the web-app).
-    return remoting::DaemonController::STATE_NOT_IMPLEMENTED;
-  }
-
-  if (exit_code == 0) {
-    return remoting::DaemonController::STATE_STARTED;
-  } else {
-    return remoting::DaemonController::STATE_STOPPED;
-  }
-}
-
-void DaemonControllerLinux::GetConfig(const GetConfigCallback& callback) {
-  // base::Unretained() is safe because we control lifetime of the thread.
-  file_io_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
-      &DaemonControllerLinux::DoGetConfig, base::Unretained(this), callback));
-}
-
-void DaemonControllerLinux::GetUsageStatsConsent(
-    const GetUsageStatsConsentCallback& done) {
-  // Crash dump collection is not implemented on Linux yet.
-  // http://crbug.com/130678.
-  done.Run(false, false, false);
-}
-
-void DaemonControllerLinux::SetConfigAndStart(
-    scoped_ptr<base::DictionaryValue> config,
-    bool /* consent */,
-    const CompletionCallback& done) {
-  // base::Unretained() is safe because we control lifetime of the thread.
-  file_io_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
-      &DaemonControllerLinux::DoSetConfigAndStart, base::Unretained(this),
-      base::Passed(&config), done));
-}
-
-void DaemonControllerLinux::UpdateConfig(
-    scoped_ptr<base::DictionaryValue> config,
-    const CompletionCallback& done_callback) {
-  file_io_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
-      &DaemonControllerLinux::DoUpdateConfig, base::Unretained(this),
-      base::Passed(&config), done_callback));
-}
-
-void DaemonControllerLinux::Stop(const CompletionCallback& done_callback) {
-  file_io_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
-      &DaemonControllerLinux::DoStop, base::Unretained(this),
-      done_callback));
-}
-
-void DaemonControllerLinux::SetWindow(void* window_handle) {
-  // noop
-}
-
-void DaemonControllerLinux::GetVersion(
-    const GetVersionCallback& done_callback) {
-  file_io_thread_.message_loop()->PostTask(FROM_HERE, base::Bind(
-      &DaemonControllerLinux::DoGetVersion, base::Unretained(this),
-      done_callback));
-}
-
-base::FilePath DaemonControllerLinux::GetConfigPath() {
-  std::string filename = "host#" + GetMd5(net::GetHostName()) + ".json";
-  return file_util::GetHomeDir().
-      Append(".config/chrome-remote-desktop").Append(filename);
-}
-
-void DaemonControllerLinux::DoGetConfig(const GetConfigCallback& callback) {
-  scoped_ptr<base::DictionaryValue> result(new base::DictionaryValue());
-
-  if (GetState() != remoting::DaemonController::STATE_NOT_IMPLEMENTED) {
-    JsonHostConfig config(GetConfigPath());
-    if (config.Read()) {
-      std::string value;
-      if (config.GetString(kHostIdConfigPath, &value)) {
-        result->SetString(kHostIdConfigPath, value);
-      }
-      if (config.GetString(kXmppLoginConfigPath, &value)) {
-        result->SetString(kXmppLoginConfigPath, value);
-      }
-    } else {
-      result.reset(); // Return NULL in case of error.
-    }
-  }
-
-  callback.Run(result.Pass());
-}
-
-void DaemonControllerLinux::DoSetConfigAndStart(
-    scoped_ptr<base::DictionaryValue> config,
-    const CompletionCallback& done_callback) {
-
-  // Add the user to chrome-remote-desktop group first.
-  std::vector<std::string> args;
-  args.push_back("--add-user");
-  int exit_code;
-  if (!RunHostScriptWithTimeout(
-          args, base::TimeDelta::FromSeconds(kSudoTimeoutSeconds),
-          &exit_code) ||
-      exit_code != 0) {
-    LOG(ERROR) << "Failed to add user to chrome-remote-desktop group.";
-    done_callback.Run(RESULT_FAILED);
-    return;
-  }
-
-  // Ensure the configuration directory exists.
-  base::FilePath config_dir = GetConfigPath().DirName();
-  if (!base::DirectoryExists(config_dir) &&
-      !file_util::CreateDirectory(config_dir)) {
-    LOG(ERROR) << "Failed to create config directory " << config_dir.value();
-    done_callback.Run(RESULT_FAILED);
-    return;
-  }
-
-  // Write config.
-  JsonHostConfig config_file(GetConfigPath());
-  if (!config_file.CopyFrom(config.get()) ||
-      !config_file.Save()) {
-    LOG(ERROR) << "Failed to update config file.";
-    done_callback.Run(RESULT_FAILED);
-    return;
-  }
-
-  // Finally start the host.
-  args.clear();
-  args.push_back("--start");
-  AsyncResult result;
-  if (RunHostScript(args, &exit_code)) {
-    result = (exit_code == 0) ? RESULT_OK : RESULT_FAILED;
-  } else {
-    result = RESULT_FAILED;
-  }
-  done_callback.Run(result);
-}
-
-void DaemonControllerLinux::DoUpdateConfig(
-    scoped_ptr<base::DictionaryValue> config,
-    const CompletionCallback& done_callback) {
-  JsonHostConfig config_file(GetConfigPath());
-  if (!config_file.Read() ||
-      !config_file.CopyFrom(config.get()) ||
-      !config_file.Save()) {
-    LOG(ERROR) << "Failed to update config file.";
-    done_callback.Run(RESULT_FAILED);
-    return;
-  }
-
-  std::vector<std::string> args;
-  args.push_back("--reload");
-  AsyncResult result;
-  int exit_code;
-  if (RunHostScript(args, &exit_code)) {
-    result = (exit_code == 0) ? RESULT_OK : RESULT_FAILED;
-  } else {
-    result = RESULT_FAILED;
-  }
-
-  done_callback.Run(result);
-}
-
-void DaemonControllerLinux::DoStop(const CompletionCallback& done_callback) {
-  std::vector<std::string> args;
-  args.push_back("--stop");
-  int exit_code = 0;
-  AsyncResult result;
-  if (RunHostScript(args, &exit_code)) {
-    result = (exit_code == 0) ? RESULT_OK : RESULT_FAILED;
-  } else {
-    result = RESULT_FAILED;
-  }
-  done_callback.Run(result);
-}
-
-void DaemonControllerLinux::DoGetVersion(
-    const GetVersionCallback& done_callback) {
-  base::FilePath script_path;
-  if (!GetScriptPath(&script_path)) {
-    done_callback.Run(std::string());
-    return;
-  }
-  CommandLine command_line(script_path);
-  command_line.AppendArg("--host-version");
-
-  std::string version;
-  int exit_code = 0;
-  int result =
-      base::GetAppOutputWithExitCode(command_line, &version, &exit_code);
-  if (!result || exit_code != 0) {
-    LOG(ERROR) << "Failed to run \"" << command_line.GetCommandLineString()
-               << "\". Exit code: " << exit_code;
-    done_callback.Run(std::string());
-    return;
-  }
-
-  TrimWhitespaceASCII(version, TRIM_ALL, &version);
-  if (!ContainsOnlyChars(version, "0123456789.")) {
-    LOG(ERROR) << "Received invalid host version number: " << version;
-    done_callback.Run(std::string());
-    return;
-  }
-
-  done_callback.Run(version);
-}
-
-}  // namespace
-
-scoped_ptr<DaemonController> remoting::DaemonController::Create() {
-  return scoped_ptr<DaemonController>(new DaemonControllerLinux());
-}
-
-}  // namespace remoting