Fix Me2Me host to properly reload config when it changes.

remoting/host/remoting_me2me_host.cc

 // 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.
 //
 // This file implements a standalone host process for Me2Me.
 
 #include <string>
 
 #include "base/at_exit.h"
 #include "base/bind.h"
@@ skipping 98 matching lines @@
     network_change_notifier_.reset(net::NetworkChangeNotifier::Create());
     config_updated_timer_.reset(new base::DelayTimer<HostProcess>(
         FROM_HERE, base::TimeDelta::FromSeconds(2), this,
         &HostProcess::ConfigUpdatedDelayed));
   }
 
   bool InitWithCommandLine(const CommandLine* cmd_line) {
     FilePath default_config_dir = remoting::GetConfigDir();
     if (cmd_line->HasSwitch(kAuthConfigSwitchName)) {
       FilePath path = cmd_line->GetSwitchValuePath(kAuthConfigSwitchName);
-      if (!config_.AddConfigPath(path)) {
-        return false;
-      }
+      config_.AddConfigPath(path);
     }
 
     host_config_path_ = default_config_dir.Append(kDefaultHostConfigFile);
     if (cmd_line->HasSwitch(kHostConfigSwitchName)) {
       host_config_path_ = cmd_line->GetSwitchValuePath(kHostConfigSwitchName);
     }
-    if (!config_.AddConfigPath(host_config_path_)) {
-      return false;
-    }
+    config_.AddConfigPath(host_config_path_);
 
     return true;

[simonmorris, 2012/08/07 01:03:02]

true -> LoadConfig() ?

[Sergey Ulanov, 2012/08/07 01:22:43]

Run() will call LoadConfig() - don't think we need to do it here. 

[simonmorris, 2012/08/07 15:48:59]

OK.

   }
 
   void ConfigUpdated() {
-    // The timer should be set and cleaned up on the same thread.
     DCHECK(message_loop_.message_loop_proxy()->BelongsToCurrentThread());
 
     // Call ConfigUpdatedDelayed after a short delay, so that this object won't
     // try to read the updated configuration file before it has been
     // completely written.
     // If the writer moves the new configuration file into place atomically,
     // this delay may not be necessary.
     config_updated_timer_->Reset();
   }
 
   void ConfigUpdatedDelayed() {
+    DCHECK(message_loop_.message_loop_proxy()->BelongsToCurrentThread());
+
     if (LoadConfig()) {
+      // PostTask to create new authenticator factory in case PIN has changed.
       context_->network_task_runner()->PostTask(
           FROM_HERE,
           base::Bind(&HostProcess::CreateAuthenticatorFactory,
                      base::Unretained(this)));
     } else {
       LOG(ERROR) << "Invalid configuration.";
     }
   }
 
 #if defined(OS_WIN)
@@ skipping 31 matching lines @@
             message_loop_.message_loop_proxy(),
             base::Bind(&HostProcess::ConfigUpdated, base::Unretained(this))));
     config_watcher_.reset(new base::files::FilePathWatcher());
     if (!config_watcher_->Watch(host_config_path_, delegate)) {
       LOG(ERROR) << "Couldn't watch file " << host_config_path_.value();
     }
 #endif
   }
 
   void CreateAuthenticatorFactory() {
+    DCHECK(context_->network_task_runner()->BelongsToCurrentThread());
     scoped_ptr<protocol::AuthenticatorFactory> factory(
         new protocol::Me2MeHostAuthenticatorFactory(
             key_pair_.GenerateCertificate(),
             *key_pair_.private_key(), host_secret_hash_));
     host_->SetAuthenticatorFactory(factory.Pass());
   }
 
   int Run() {
     if (!LoadConfig()) {
       return kInvalidHostConfigurationExitCode;
@@ skipping 34 matching lines @@
  private:
   void StartWatchingPolicy() {
     policy_watcher_.reset(
         policy_hack::PolicyWatcher::Create(context_->file_task_runner()));
     policy_watcher_->StartWatching(
         base::Bind(&HostProcess::OnPolicyUpdate, base::Unretained(this)));
   }
 
   // Read host config, returning true if successful.
   bool LoadConfig() {
+    DCHECK(message_loop_.message_loop_proxy()->BelongsToCurrentThread());
+
+    // TODO(sergeyu): There is a potential race condition: this function is
+    // called on the main thread while the class members it mutates are used on
+    // the network thread. Fix it. http://crbug.com/140986 .
+
+    if (!config_.Read()) {
+      LOG(ERROR) << "Failed to read config file.";
+      return false;
+    }
+
     if (!config_.GetString(kHostIdConfigPath, &host_id_)) {
       LOG(ERROR) << "host_id is not defined in the config.";
       return false;
     }
 
     if (!key_pair_.Load(config_)) {
       return false;
     }
 
     std::string host_secret_hash_string;
@@ skipping 373 matching lines @@
             user32.GetFunctionPointer("SetProcessDPIAware"));
     set_process_dpi_aware();
   }
 
   // CommandLine::Init() ignores the passed |argc| and |argv| on Windows getting
   // the command line from GetCommandLineW(), so we can safely pass NULL here.
   return main(0, NULL);
 }
 
 #endif  // defined(OS_WIN)