When re-launching the application after an update is installed, do it from a non-elevated process.

Previously the application was restarted from the main install process, which may have
  been elevated.  The main application must be started from a non-elevated updater/updater.exe
  process otherwise the main app will inherit the elevated status from its parent.

  * Modify ProcessUtils::runElevated() to return the status code of the process
  * Change UpdateInstaller to run the main installation synchronously from the initial
    updater process in the case where elevation is not required.
  * Remove calls in main.cpp to relaunch the main application after the UI is closed.

src/ProcessUtils.cpp

@@ -71,15 +71,15 @@ void ProcessUtils::runAsync(const std::string& executable,
 #endif
 }
 
-void ProcessUtils::runElevated(const std::string& executable,
+int ProcessUtils::runElevated(const std::string& executable,
 					const std::list<std::string>& args)
 {
 #ifdef PLATFORM_WINDOWS
-	runElevatedWindows(executable,args);
+	return runElevatedWindows(executable,args);
 #elif defined(PLATFORM_MAC)
-	runElevatedMac(executable,args);
+	return runElevatedMac(executable,args);
 #elif defined(PLATFORM_LINUX)
-	runElevatedLinux(executable,args);
+	return runElevatedLinux(executable,args);
 #endif
 }
 
@@ -114,7 +114,7 @@ bool ProcessUtils::waitForProcess(PLATFORM_PID pid)
 }
 
 #ifdef PLATFORM_LINUX
-void ProcessUtils::runElevatedLinux(const std::string& executable,
+int ProcessUtils::runElevatedLinux(const std::string& executable,
 							const std::list<std::string>& args)
 {
 	std::string sudoMessage = FileOps::fileName(executable.c_str()) + " needs administrative privileges.  Please enter your password.";
@@ -152,9 +152,11 @@ void ProcessUtils::runElevatedLinux(const std::string& executable,
 		int result = ProcessUtils::runSync(sudoBinary,sudoArgs);
 		if (result != 255)
 		{
+			return result;
 			break;
 		}
 	}
+	return RUN_ELEVATED_FAILED;
 }
 #endif
 
@@ -245,10 +247,13 @@ void ProcessUtils::runElevatedMac(const std::string& executable,
 				{
 					LOG(Info,"elevated process succeded with pid " + intToStr(childPid));
 				}
+
+				return childStatus;
 			}
 			else
 			{
 				LOG(Error,"failed to launch elevated process " + intToStr(status));
+				return RUN_ELEVATED_FAILED;
 			}
 			
 			// If we want to know more information about what has happened:
@@ -262,13 +267,18 @@ void ProcessUtils::runElevatedMac(const std::string& executable,
 		else
 		{
 			LOG(Error,"failed to get rights to launch elevated process. status: " + intToStr(status));
+			return RUN_ELEVATED_FAILED;
 		}
 	}
+	else
+	{
+		return RUN_ELEVATED_FAILED;
+	}
 }
 #endif
 
 #ifdef PLATFORM_WINDOWS
-void ProcessUtils::runElevatedWindows(const std::string& executable,
+int ProcessUtils::runElevatedWindows(const std::string& executable,
 							const std::list<std::string>& arguments)
 {
 	std::string args;
@@ -304,10 +314,14 @@ void ProcessUtils::runElevatedWindows(const std::string& executable,
 	if (!ShellExecuteEx(&executeInfo))
 	{
 		LOG(Error,"Failed to start with admin priviledges using ShellExecuteEx()");
-		return;
+		return RUN_ELEVATED_FAILED;
 	}
 
 	WaitForSingleObject(executeInfo.hProcess, INFINITE);
+
+	// this assumes the process succeeded - we need to check whether
+	// this is actually the case.
+	return 0;
 }
 #endif
 

src/ProcessUtils.h

@@ -8,6 +8,14 @@
 class ProcessUtils
 {
 	public:
+		enum Errors
+		{
+			/** Status code returned by runElevated() if launching
+			  * the elevated process fails.
+			  */
+			RUN_ELEVATED_FAILED = 255
+		};
+
 		static PLATFORM_PID currentProcessId();
 
 		static std::string currentProcessPath();
@@ -18,7 +26,13 @@ class ProcessUtils
 		static void runAsync(const std::string& executable,
 		                     const std::list<std::string>& args);
 
-		static void runElevated(const std::string& executable,
+		/** Run a process with administrative privileges and return the
+		  * status code of the process, or 0 on Windows.
+		  *
+		  * Returns RUN_ELEVATED_FAILED if the elevated process could
+		  * not be started.
+		  */
+		static int runElevated(const std::string& executable,
 		                        const std::list<std::string>& args);
 
 		static bool waitForProcess(PLATFORM_PID pid);
@@ -32,11 +46,11 @@ class ProcessUtils
 #endif
 
 	private:
-		static void runElevatedLinux(const std::string& executable,
+		static int runElevatedLinux(const std::string& executable,
 		                             const std::list<std::string>& args);
-		static void runElevatedMac(const std::string& executable,
+		static int runElevatedMac(const std::string& executable,
 		                           const std::list<std::string>& args);
-		static void runElevatedWindows(const std::string& executable,
+		static int runElevatedWindows(const std::string& executable,
 		                               const std::list<std::string>& args);
 
 		static PLATFORM_PID runAsyncUnix(const std::string& executable,

src/UpdateInstaller.cpp

@@ -98,20 +98,40 @@ void UpdateInstaller::run() throw ()
 		args.push_back("--wait");
 		args.push_back(intToStr(ProcessUtils::currentProcessId()));
 
+		int installStatus = 0;
 		if (!checkAccess())
 		{
 			LOG(Info,"Insufficient rights to install app to " + m_installDir + " requesting elevation");
 
 			// start a copy of the updater with admin rights
-			ProcessUtils::runElevated(updaterPath,args);
+			installStatus = ProcessUtils::runElevated(updaterPath,args);
 		}
 		else
 		{
 			LOG(Info,"Sufficient rights to install app - restarting with same permissions");
-
+			installStatus = ProcessUtils::runSync(updaterPath,args);
-			// TODO - Change this to run synchronously
-			ProcessUtils::runAsync(updaterPath,args);
 		}
+
+		if (installStatus == 0)
+		{
+			LOG(Info,"Update install completed");
+		}
+		else
+		{
+			LOG(Error,"Update install failed with status " + intToStr(installStatus));
+		}
+
+		// restart the main application - this is currently done
+		// regardless of whether the installation succeeds or not
+		restartMainApp();
+
+		// clean up files created by the updater
+		std::list<std::string> cleanupArgs = updaterArgs();
+		cleanupArgs.push_back("--mode");
+		cleanupArgs.push_back("cleanup");
+		cleanupArgs.push_back("--wait");
+		cleanupArgs.push_back(intToStr(ProcessUtils::currentProcessId()));
+		ProcessUtils::runAsync(updaterPath,cleanupArgs);
 	}
 	else if (m_mode == Main)
 	{
@@ -152,13 +172,6 @@ void UpdateInstaller::run() throw ()
 		{
 			m_observer->updateFinished();
 		}
-
-		std::list<std::string> args = updaterArgs();
-		args.push_back("--mode");
-		args.push_back("cleanup");
-		args.push_back("--wait");
-		args.push_back(intToStr(ProcessUtils::currentProcessId()));
-		ProcessUtils::runAsync(updaterPath,args);
 	}
 	else if (m_mode == Cleanup)
 	{

src/main.cpp

@@ -94,15 +94,9 @@ void runWithUi(int argc, char** argv, UpdateInstaller* installer)
 	tthread::thread updaterThread(runUpdaterThread,installer);
 	dialog.exec();
 	updaterThread.join();
-
-	if (dialog.restartApp())
-	{
-		installer->restartMainApp();
-	}
 #else
 	// no UI available - do a silent install
 	installer->run();
-	installer->restartMainApp();
 #endif
 }
 #endif
@@ -116,7 +110,6 @@ void runWithUi(int argc, char** argv, UpdateInstaller* installer)
 	tthread::thread updaterThread(runUpdaterThread,installer);
 	dialog.exec();
 	updaterThread.join();
-	installer->restartMainApp();
 }
 #endif
 
@@ -141,6 +134,5 @@ void runWithUi(int argc, char** argv, UpdateInstaller* installer)
 	tthread::thread updaterThread(runUpdaterThread,installer);
 	dialog.exec();
 	updaterThread.join();
-	installer->restartMainApp();
 }
 #endif