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

remoting/host/setup/daemon_controller_delegate_mac.mm

+// Copyright 2013 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 <CoreFoundation/CoreFoundation.h>
+
+#include "remoting/host/setup/daemon_controller_delegate_mac.h"
+
+#include <launch.h>
+#include <stdio.h>
+#include <sys/types.h>
+
+#include "base/basictypes.h"
+#include "base/bind.h"
+#include "base/compiler_specific.h"
+#include "base/file_util.h"
+#include "base/files/file_path.h"
+#include "base/json/json_writer.h"
+#include "base/logging.h"
+#include "base/mac/foundation_util.h"
+#include "base/mac/launchd.h"
+#include "base/mac/mac_logging.h"
+#include "base/mac/mac_util.h"
+#include "base/mac/scoped_launch_data.h"
+#include "base/time/time.h"
+#include "base/values.h"
+#include "remoting/host/constants_mac.h"
+#include "remoting/host/json_host_config.h"
+#include "remoting/host/usage_stats_consent.h"
+
+namespace remoting {
+
+DaemonControllerDelegateMac::DaemonControllerDelegateMac() {
+}
+
+DaemonControllerDelegateMac::~DaemonControllerDelegateMac() {
+  DeregisterForPreferencePaneNotifications();
+}
+
+DaemonController::State DaemonControllerDelegateMac::GetState() {
+  pid_t job_pid = base::mac::PIDForJob(kServiceName);
+  if (job_pid < 0) {
+    return DaemonController::STATE_NOT_INSTALLED;
+  } else if (job_pid == 0) {
+    // Service is stopped, or a start attempt failed.
+    return DaemonController::STATE_STOPPED;
+  } else {
+    return DaemonController::STATE_STARTED;
+  }
+}
+
+scoped_ptr<base::DictionaryValue> DaemonControllerDelegateMac::GetConfig() {
+  base::FilePath config_path(kHostConfigFilePath);
+  JsonHostConfig host_config(config_path);
+  scoped_ptr<base::DictionaryValue> config;
+
+  if (host_config.Read()) {
+    config.reset(new base::DictionaryValue());
+    std::string value;
+    if (host_config.GetString(kHostIdConfigPath, &value))
+      config.get()->SetString(kHostIdConfigPath, value);
+    if (host_config.GetString(kXmppLoginConfigPath, &value))
+      config.get()->SetString(kXmppLoginConfigPath, value);
+  }
+
+  return config.Pass();
+}
+
+void DaemonControllerDelegateMac::SetConfigAndStart(
+    scoped_ptr<base::DictionaryValue> config,
+    bool consent,
+    const DaemonController::CompletionCallback& done) {
+  config->SetBoolean(kUsageStatsConsentConfigPath, consent);
+  std::string config_data;
+  base::JSONWriter::Write(config.get(), &config_data);
+  ShowPreferencePane(config_data, done);
+}
+
+void DaemonControllerDelegateMac::UpdateConfig(
+    scoped_ptr<base::DictionaryValue> config,
+    const DaemonController::CompletionCallback& done) {
+  base::FilePath config_file_path(kHostConfigFilePath);
+  JsonHostConfig config_file(config_file_path);
+  if (!config_file.Read()) {
+    done.Run(DaemonController::RESULT_FAILED);
+    return;
+  }
+  if (!config_file.CopyFrom(config.get())) {
+    LOG(ERROR) << "Failed to update configuration.";
+    done.Run(DaemonController::RESULT_FAILED);
+    return;
+  }
+
+  std::string config_data = config_file.GetSerializedData();
+  ShowPreferencePane(config_data, done);
+}
+
+void DaemonControllerDelegateMac::Stop(
+    const DaemonController::CompletionCallback& done) {
+  ShowPreferencePane("", done);
+}
+
+void DaemonControllerDelegateMac::SetWindow(void* window_handle) {
+  // noop
+}
+
+std::string DaemonControllerDelegateMac::GetVersion() {
+  std::string version = "";
+  std::string command_line = remoting::kHostHelperScriptPath;
+  command_line += " --host-version";
+  FILE* script_output = popen(command_line.c_str(), "r");
+  if (script_output) {
+    char buffer[100];
+    char* result = fgets(buffer, sizeof(buffer), script_output);
+    pclose(script_output);
+    if (result) {
+      // The string is guaranteed to be null-terminated, but probably contains
+      // a newline character, which we don't want.
+      for (int i = 0; result[i]; ++i) {
+        if (result[i] < ' ') {
+          result[i] = 0;
+          break;
+        }
+      }
+      version = result;
+    }
+  }
+
+  return version;
+}
+
+DaemonController::UsageStatsConsent
+DaemonControllerDelegateMac::GetUsageStatsConsent() {
+  DaemonController::UsageStatsConsent consent;
+  consent.supported = true;
+  consent.allowed = false;
+  // set_by_policy is not yet supported.
+  consent.set_by_policy = false;
+
+  base::FilePath config_file_path(kHostConfigFilePath);
+  JsonHostConfig host_config(config_file_path);
+  if (host_config.Read()) {
+    host_config.GetBoolean(kUsageStatsConsentConfigPath, &consent.allowed);
+  }
+
+  return consent;
+}
+
+void DaemonControllerDelegateMac::ShowPreferencePane(
+    const std::string& config_data,
+    const DaemonController::CompletionCallback& done) {
+  if (DoShowPreferencePane(config_data)) {
+    RegisterForPreferencePaneNotifications(done);
+  } else {
+    done.Run(DaemonController::RESULT_FAILED);
+  }
+}
+
+// CFNotificationCenterAddObserver ties the thread on which distributed
+// notifications are received to the one on which it is first called.
+// This is safe because HostNPScriptObject::InvokeAsyncResultCallback
+// bounces the invocation to the correct thread, so it doesn't matter
+// which thread CompletionCallbacks are called on.
+void DaemonControllerDelegateMac::RegisterForPreferencePaneNotifications(
+    const DaemonController::CompletionCallback& done) {
+  // We can only have one callback registered at a time. This is enforced by the
+  // UX flow of the web-app.
+  DCHECK(current_callback_.is_null());
+  current_callback_ = done;
+
+  CFNotificationCenterAddObserver(
+      CFNotificationCenterGetDistributedCenter(),
+      this,
+      &DaemonControllerDelegateMac::PreferencePaneCallback,
+      CFSTR(UPDATE_SUCCEEDED_NOTIFICATION_NAME),
+      NULL,
+      CFNotificationSuspensionBehaviorDeliverImmediately);
+  CFNotificationCenterAddObserver(
+      CFNotificationCenterGetDistributedCenter(),
+      this,
+      &DaemonControllerDelegateMac::PreferencePaneCallback,
+      CFSTR(UPDATE_FAILED_NOTIFICATION_NAME),
+      NULL,
+      CFNotificationSuspensionBehaviorDeliverImmediately);
+}
+
+void DaemonControllerDelegateMac::DeregisterForPreferencePaneNotifications() {
+  CFNotificationCenterRemoveObserver(
+      CFNotificationCenterGetDistributedCenter(),
+      this,
+      CFSTR(UPDATE_SUCCEEDED_NOTIFICATION_NAME),
+      NULL);
+  CFNotificationCenterRemoveObserver(
+      CFNotificationCenterGetDistributedCenter(),
+      this,
+      CFSTR(UPDATE_FAILED_NOTIFICATION_NAME),
+      NULL);
+}
+
+void DaemonControllerDelegateMac::PreferencePaneCallbackDelegate(
+    CFStringRef name) {
+  DaemonController::AsyncResult result = DaemonController::RESULT_FAILED;
+  if (CFStringCompare(name, CFSTR(UPDATE_SUCCEEDED_NOTIFICATION_NAME), 0) ==
+          kCFCompareEqualTo) {
+    result = DaemonController::RESULT_OK;
+  } else if (CFStringCompare(name, CFSTR(UPDATE_FAILED_NOTIFICATION_NAME), 0) ==
+          kCFCompareEqualTo) {
+    result = DaemonController::RESULT_FAILED;
+  } else {
+    LOG(WARNING) << "Ignoring unexpected notification: " << name;
+    return;
+  }
+
+  DCHECK(!current_callback_.is_null());
+  DaemonController::CompletionCallback done = current_callback_;
+  current_callback_.Reset();
+  done.Run(result);
+
+  DeregisterForPreferencePaneNotifications();
+}
+
+// static
+bool DaemonControllerDelegateMac::DoShowPreferencePane(
+    const std::string& config_data) {
+  if (!config_data.empty()) {
+    base::FilePath config_path;
+    if (!file_util::GetTempDir(&config_path)) {
+      LOG(ERROR) << "Failed to get filename for saving configuration data.";
+      return false;
+    }
+    config_path = config_path.Append(kHostConfigFileName);
+
+    int written = file_util::WriteFile(config_path, config_data.data(),
+                                       config_data.size());
+    if (written != static_cast<int>(config_data.size())) {
+      LOG(ERROR) << "Failed to save configuration data to: "
+                 << config_path.value();
+      return false;
+    }
+  }
+
+  base::FilePath pane_path;
+  // TODO(lambroslambrou): Use NSPreferencePanesDirectory once we start
+  // building against SDK 10.6.
+  if (!base::mac::GetLocalDirectory(NSLibraryDirectory, &pane_path)) {
+    LOG(ERROR) << "Failed to get directory for local preference panes.";
+    return false;
+  }
+  pane_path = pane_path.Append("PreferencePanes").Append(kPrefPaneFileName);
+
+  FSRef pane_path_ref;
+  if (!base::mac::FSRefFromPath(pane_path.value(), &pane_path_ref)) {
+    LOG(ERROR) << "Failed to create FSRef";
+    return false;
+  }
+  OSStatus status = LSOpenFSRef(&pane_path_ref, NULL);
+  if (status != noErr) {
+    OSSTATUS_LOG(ERROR, status) << "LSOpenFSRef failed for path: "
+                                << pane_path.value();
+    return false;
+  }
+
+  CFNotificationCenterRef center =
+      CFNotificationCenterGetDistributedCenter();
+  base::ScopedCFTypeRef<CFStringRef> service_name(CFStringCreateWithCString(
+      kCFAllocatorDefault, remoting::kServiceName, kCFStringEncodingUTF8));
+  CFNotificationCenterPostNotification(center, service_name, NULL, NULL,
+                                       TRUE);
+  return true;
+}
+
+// static
+void DaemonControllerDelegateMac::PreferencePaneCallback(
+    CFNotificationCenterRef center,
+    void* observer,
+    CFStringRef name,
+    const void* object,
+    CFDictionaryRef user_info) {
+  DaemonControllerDelegateMac* self =
+      reinterpret_cast<DaemonControllerDelegateMac*>(observer);
+  if (!self) {
+    LOG(WARNING) << "Ignoring notification with NULL observer: " << name;
+    return;
+  }
+
+  self->PreferencePaneCallbackDelegate(name);
+}
+
+scoped_refptr<DaemonController> DaemonController::Create() {
+  scoped_ptr<DaemonController::Delegate> delegate(
+      new DaemonControllerDelegateMac());
+  return new DaemonController(delegate.Pass());
+}
+
+}  // namespace remoting