Pass error messages from native messaging to web-app.

remoting/host/setup/daemon_controller_delegate_linux.cc

 // 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 "remoting/host/setup/daemon_controller_delegate_linux.h"
 
 #include <unistd.h>
 
 #include "base/base_paths.h"
 #include "base/basictypes.h"
@@ skipping 47 matching lines @@
   if (access(candidate_exe.value().c_str(), X_OK) == 0) {
     *result = candidate_exe;
     return true;
   }
   return false;
 }
 
 bool RunHostScriptWithTimeout(
     const std::vector<std::string>& args,
     base::TimeDelta timeout,
-    int* exit_code) {
-  DCHECK(exit_code);
+    const DaemonController::ErrorCallback& on_error) {
 
   // 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.";
+    std::string error_message = "Refusing to run script as root";
+    LOG(ERROR) << error_message;
+    on_error.Run(error_message, FROM_HERE);
     return false;
   }
+
   base::FilePath script_path;
   if (!GetScriptPath(&script_path)) {
-    LOG(ERROR) << "GetScriptPath() failed.";
+    std::string error_message = "GetScriptPath() failed";
+    LOG(ERROR) << error_message;
+    on_error.Run(error_message, FROM_HERE);
     return false;
   }
+
   base::CommandLine command_line(script_path);
   for (unsigned int i = 0; i < args.size(); ++i) {
     command_line.AppendArg(args[i]);
   }
 
   // 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 !defined(OS_CHROMEOS)
   options.allow_new_privs = true;
 #endif
 
   base::Process process = base::LaunchProcess(command_line, options);
   if (!process.IsValid()) {
-    LOG(ERROR) << "Failed to run command: "
-               << command_line.GetCommandLineString();
+    std::ostringstream error_message;
+    error_message << "Failed to run command: "
+                  << command_line.GetCommandLineString();
+    LOG(ERROR) << error_message;
+    on_error.Run(error_message.str(), FROM_HERE);
     return false;
   }
 
-  if (!process.WaitForExitWithTimeout(timeout, exit_code)) {
+  int exit_code;
+  if (!process.WaitForExitWithTimeout(timeout, &exit_code)) {
     process.Terminate(0, false);
-    LOG(ERROR) << "Timeout exceeded for command: "
-               << command_line.GetCommandLineString();
+    std::ostringstream error_message;
+    error_message << "Timeout exceeded for command: "
+                  << command_line.GetCommandLineString();
+    LOG(ERROR) << error_message;
+    on_error.Run(error_message.str(), FROM_HERE);
     return false;
   }
 
+  if (exit_code != 0) {
+    std::ostringstream error_message;
+    error_message << "Non-zero exit code " << exit_code << " from command: "
+                  << command_line.GetCommandLineString();
+    LOG(ERROR) << error_message;
+    on_error.Run(error_message.str(), FROM_HERE);
+  }
+
   return true;
 }
 
-bool RunHostScript(const std::vector<std::string>& args, int* exit_code) {
+bool RunHostScript(const std::vector<std::string>& args,
+                   const DaemonController::ErrorCallback& on_error) {
   return RunHostScriptWithTimeout(
-      args, base::TimeDelta::FromMilliseconds(kDaemonTimeoutMs), exit_code);
+      args,
+      base::TimeDelta::FromMilliseconds(kDaemonTimeoutMs),
+      on_error);
 }
 
 }  // namespace
 
 DaemonControllerDelegateLinux::DaemonControllerDelegateLinux() {
 }
 
 DaemonControllerDelegateLinux::~DaemonControllerDelegateLinux() {
 }
 
 DaemonController::State DaemonControllerDelegateLinux::GetState() {
   base::FilePath script_path;
   if (!GetScriptPath(&script_path)) {
-    LOG(ERROR) << "GetScriptPath() failed.";
+    LOG(ERROR) << "GetScriptPath() failed";
     return DaemonController::STATE_UNKNOWN;
   }
   base::CommandLine command_line(script_path);
   command_line.AppendArg("--get-status");
 
   std::string status;
   int exit_code = 0;
   if (!base::GetAppOutputWithExitCode(command_line, &status, &exit_code) ||
       exit_code != 0) {
     LOG(ERROR) << "Failed to run \"" << command_line.GetCommandLineString()
@@ skipping 32 matching lines @@
   }
   if (config->GetString(kXmppLoginConfigPath, &value)) {
     result->SetString(kXmppLoginConfigPath, value);
   }
   return result.Pass();
 }
 
 void DaemonControllerDelegateLinux::SetConfigAndStart(
     scoped_ptr<base::DictionaryValue> config,
     bool consent,
-    const DaemonController::CompletionCallback& done) {
+    const base::Closure& on_done,
+    const DaemonController::ErrorCallback& on_error) {
   // 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.Run(DaemonController::RESULT_FAILED);
+          on_error)) {
     return;
   }
 
   // Ensure the configuration directory exists.
   base::FilePath config_dir = GetConfigPath().DirName();
   if (!base::DirectoryExists(config_dir) &&
       !base::CreateDirectory(config_dir)) {
-    LOG(ERROR) << "Failed to create config directory " << config_dir.value();
-    done.Run(DaemonController::RESULT_FAILED);
+    std::ostringstream error_message;
+    error_message << "Failed to create config directory " << config_dir.value();
+    LOG(ERROR) << error_message;
+    on_error.Run(error_message.str(), FROM_HERE);
     return;
   }
 
   // Write config.
   if (!HostConfigToJsonFile(*config, GetConfigPath())) {
-    LOG(ERROR) << "Failed to update config file.";
-    done.Run(DaemonController::RESULT_FAILED);
+    std::string error_message = "Failed to update config file";
+    LOG(ERROR) << error_message;
+    on_error.Run(error_message, FROM_HERE);
     return;
   }
 
   // Finally start the host.
   args.clear();
   args.push_back("--start");
-  DaemonController::AsyncResult result = DaemonController::RESULT_FAILED;
-  if (RunHostScript(args, &exit_code) && (exit_code == 0))
-    result = DaemonController::RESULT_OK;
-
-  done.Run(result);
+  if (RunHostScript(args, on_error)) {
+    on_done.Run();
+  }
 }
 
 void DaemonControllerDelegateLinux::UpdateConfig(
     scoped_ptr<base::DictionaryValue> config,
-    const DaemonController::CompletionCallback& done) {
+    const base::Closure& on_done,
+    const DaemonController::ErrorCallback& on_error) {
   scoped_ptr<base::DictionaryValue> new_config(
       HostConfigFromJsonFile(GetConfigPath()));
-  if (new_config)
-    new_config->MergeDictionary(config.get());
-  if (!new_config || !HostConfigToJsonFile(*new_config, GetConfigPath())) {
-    LOG(ERROR) << "Failed to update config file.";
-    done.Run(DaemonController::RESULT_FAILED);
+  if (!new_config) {
+    std::ostringstream error_message;
+    error_message << "Reading config from " << GetConfigPath().value()
+                  << " failed";
+    LOG(ERROR) << error_message;
+    on_error.Run(error_message.str(), FROM_HERE);
+    return;
+  }
+
+  new_config->MergeDictionary(config.get());
+  if (!HostConfigToJsonFile(*new_config, GetConfigPath())) {
+    std::ostringstream error_message;
+    error_message << "Writing config to " << GetConfigPath().value()
+                  << " failed";
+    LOG(ERROR) << error_message;
+    on_error.Run(error_message.str(), FROM_HERE);
     return;
   }
 
   std::vector<std::string> args;
   args.push_back("--reload");
-  int exit_code = 0;
-  DaemonController::AsyncResult result = DaemonController::RESULT_FAILED;
-  if (RunHostScript(args, &exit_code) && (exit_code == 0))
-    result = DaemonController::RESULT_OK;
-
-  done.Run(result);
+  if (RunHostScript(args, on_error)) {
+    on_done.Run();
+  }
 }
 
 void DaemonControllerDelegateLinux::Stop(
-    const DaemonController::CompletionCallback& done) {
+    const base::Closure& on_done,
+    const DaemonController::ErrorCallback& on_error) {
   std::vector<std::string> args;
   args.push_back("--stop");
-  int exit_code = 0;
-  DaemonController::AsyncResult result = DaemonController::RESULT_FAILED;
-  if (RunHostScript(args, &exit_code) && (exit_code == 0))
-    result = DaemonController::RESULT_OK;
-
-  done.Run(result);
+  if (RunHostScript(args, on_error)) {
+    on_done.Run();
+  }
 }
 
 DaemonController::UsageStatsConsent
 DaemonControllerDelegateLinux::GetUsageStatsConsent() {
   // Crash dump collection is not implemented on Linux yet.
   // http://crbug.com/130678.
   DaemonController::UsageStatsConsent consent;
   consent.supported = false;
   consent.allowed = false;
   consent.set_by_policy = false;
   return consent;
 }
 
 scoped_refptr<DaemonController> DaemonController::Create() {
   scoped_ptr<DaemonController::Delegate> delegate(
       new DaemonControllerDelegateLinux());
   return new DaemonController(delegate.Pass());
 }
 
 }  // namespace remoting