/*
 * FDBService.cpp
 *
 * This source file is part of the FoundationDB open source project
 *
 * Copyright 2013-2018 Apple Inc. and the FoundationDB project authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "ServiceBase.h"
#include "ThreadPool.h"

#include <iostream>
#include <fstream>
#include <unordered_map>

#include <stdint.h>
#include <time.h>

#include "..\flow\SimpleOpt.h"
#include "..\fdbmonitor\SimpleIni.h"
#include "fdbclient/versions.h"

// For PathFileExists
#include "Shlwapi.h"
#pragma comment(lib, "Shlwapi.lib")
// For SHGetFolderPath
#include <ShlObj.h>
#pragma comment(lib, "Shell32.lib")

// To be used for logging, naming of Mutex, etc.
#ifdef __FDB_DOC_MONITOR__
	#define SERVICE_NAME             "fdbdocmonitor"
	#define CONFIG_NAME              "document\\document.conf"
#else // __FDB_KVS_MONITOR__
	#define SERVICE_NAME             "fdbmonitor"
	#define CONFIG_NAME              "foundationdb.conf"
#endif


// Set up the options parsing. We have only one option now, but this could change!
enum { OPT_CONFFILE };
CSimpleOpt::SOption g_rgOptions[] = {
	{ OPT_CONFFILE, "--conffile", SO_REQ_SEP },
	SO_END_OF_OPTIONS
};


// For logging debugging messages
bool logging = false;
std::ofstream logFile;

std::string format( const char* form, ... ) {
	char buf[200];
	va_list args;

	va_start(args, form);
	int size = vsnprintf(buf, sizeof(buf), form, args);
	va_end(args);

	if(size >= 0 && size < sizeof(buf)) {
		return std::string(buf, size);
	}

	#ifdef _WIN32
	// Microsoft's non-standard vsnprintf doesn't return a correct size, but just an error, so determine the necessary size
	va_start(args, form);
	size = _vscprintf(form, args);
	va_end(args);
	#endif

	if (size < 0) throw std::exception("Error in format");

	std::string s;
	s.resize(size + 1);
	va_start(args, form);
	size = vsnprintf(&s[0], s.size(), form, args);
	va_end(args);
	if (size < 0 || size >= s.size()) throw std::exception("Error in format");

	s.resize(size);
	return s;
}

void writeLogLine(std::string message) {
	if( logging && logFile.good() ) {
		char datebuf[128], timebuf[128];
		_strdate_s( datebuf, 128 );
		_strtime_s( timebuf, 128 );
		logFile << datebuf << " " << timebuf << " - " << message << "\n";
		logFile.flush();
	}
}


class FDBService : public CServiceBase
{
public:
	FDBService(bool fCanStop = true,
				bool fCanShutdown = true,
				bool fCanPauseContinue = false)
				: CServiceBase(SERVICE_NAME, fCanStop, fCanShutdown, fCanPauseContinue), serviceStopping( false )
	{
		// Create a manual-reset event to signal the end of the service.
		stoppedEvent = CreateEvent(NULL, true, false, NULL);
		if (stoppedEvent == NULL)
		{
			throw GetLastError();
		}
		// Create a manual-reset event to signal the end of the service.
		stoppingEvent = CreateEvent(NULL, true, false, NULL);
		if (stoppingEvent == NULL)
		{
			throw GetLastError();
		}

		// Initialize child job member
		childJob = NULL;
	}

	virtual ~FDBService(void) {
		if (stoppedEvent) {
			CloseHandle(stoppedEvent);
			stoppedEvent = NULL;
		}
		if (stoppingEvent) {
			CloseHandle(stoppingEvent);
			stoppingEvent = NULL;
		}
		if(childJob) {
			CloseHandle(childJob);
			childJob = NULL;
		}
		logFile.close();
	};

	// The following method will allow the object to run
	// within the foreground
	virtual bool Run(void)
	{
		int	status = 0;

		// Start the service
		try
		{
			// Define the configuration file
			confFile = GetDefaultConfigFilePath();

			// Run the worker thread
			ServiceWorkerThread();
		}
		catch (DWORD dwError)
		{
			// Log the error.
			WriteErrorLogEntry("Service Start", dwError);
			status++;
		}
		catch (...)
		{
			// Log the error.
			WriteEventLogEntry("Service failed to start.", EVENTLOG_ERROR_TYPE);
			status++;
		}

		return (status == 0);
	}

protected:
	// The following function will return the default configuration
	// file path
	std::string	GetDefaultConfigFilePath()
	{
		TCHAR programData[MAX_PATH];
		if (SHGetFolderPath(NULL, CSIDL_COMMON_APPDATA, NULL, 0, programData) != S_OK)
		{
			errorExit("resolving CSIDL_COMMON_APPDATA");
		}

		return std::string(programData) + "\\foundationdb\\" + CONFIG_NAME;
	}

	struct Command {
		std::string binary;
		std::string args;
		std::string section;
		std::string ssection;
		int restartDelay;
		boolean quiet;
		boolean valid;

		Command() : valid( false ), quiet( false ), restartDelay( 5 ) {}

		bool operator != ( const Command& rhs ) {
			return binary != rhs.binary || args != rhs.args;
		}
	};

	struct Subprocess {
		// Represents a single subprocess which is in the configuration file.  It is either running
		// or waiting (on a timer) to restart.

		// Interface to event loop
		Subprocess( FDBService* svc, int id, Command const& cmd ) : svc(svc), id(id), command(cmd), process_or_timer(INVALID_HANDLE_VALUE), isProcess(true) {
			createProcess();
		}
		~Subprocess() {
			if (isProcess) {
				// FIXME: should this be other than 0? Should we care if this fails?
				if( !TerminateProcess( process_or_timer, 0 ) ) {
					svc->errorExit("Terminate fdbmonitor process");
				}

				// TerminateProcess is asynchronous, wait for the process to die
				if( !command.quiet )
					svc->LogEvent( EVENTLOG_INFORMATION_TYPE, format( "Waiting for process %d to terminate", id ) );
				DWORD signal = WaitForSingleObject( process_or_timer, INFINITE );
				if( signal != WAIT_OBJECT_0 ) {
					svc->errorExit("Termination wait for process");
				} else if( !command.quiet ) {
					svc->LogEvent( EVENTLOG_INFORMATION_TYPE, format( "Process %d has terminated", id ) );
				}
			}

			CloseHandle( process_or_timer );
		}
		HANDLE getHandleToWaitOn() { return process_or_timer; }
		void onHandleSignaled() {
			if (isProcess) {
				DWORD exitCode;
				if( !GetExitCodeProcess(process_or_timer, &exitCode) ) {
					svc->logLastError("process get exit code");
					exitCode = 2181;  // FIXME: WHAT?
				}

				if( !command.quiet )
					svc->LogEvent( EVENTLOG_INFORMATION_TYPE, 
						format( "Child process %d exited with %d, restarting in %d seconds",
							id, exitCode, command.restartDelay ) );

				CloseHandle( process_or_timer );
				startTimer();
			} else {
				CloseHandle( process_or_timer );
				createProcess();
			}
		}

		// Intrusive indices for external data structures
		int id;
		size_t subprocess_index;

		// Configuration and state
		FDBService* svc;
		Command command;
		HANDLE process_or_timer;
		bool isProcess;  // otherwise, is waiting to restart

		// Implementation
		void startTimer() {
			isProcess = false;
			process_or_timer = CreateWaitableTimer(NULL, TRUE, NULL);
			if( !process_or_timer )
				svc->errorExit( format( "Error in startTimer(): CreateWaitableTimer (%d)", GetLastError() ).c_str() );

			svc->startTimer(process_or_timer, command.restartDelay);
		}

		void createProcess() {
			isProcess = true;

			STARTUPINFO si;
			PROCESS_INFORMATION pi;

			ZeroMemory( &si, sizeof(si) );
			si.cb = sizeof(si);
			ZeroMemory( &pi, sizeof(pi) );

			if( !command.quiet )
				svc->LogEvent( EVENTLOG_INFORMATION_TYPE, format( "Starting child job (%s)", command.args.c_str() ) );

			// Start the child process.
			if (!CreateProcess(command.binary.c_str(),   // Command's binary
				(char *)command.args.c_str(),             // Command's args
				NULL,           // Process handle not inheritable
				NULL,           // Thread handle not inheritable
				FALSE,          // Set handle inheritance to FALSE
				CREATE_NEW_PROCESS_GROUP,              // No flags for creation
				NULL,           // Use parent's environment block
				NULL,           // Use parent's starting directory 
				&si,            // Pointer to STARTUPINFO structure
				&pi )           // Pointer to PROCESS_INFORMATION structure
			) {
				svc->logLastError( format("Failed to create process, restarting in %d seconds (%s)",
					command.restartDelay, command.args.c_str()).c_str() );

				// If there was an error, we set a timer right away for the restart.
				startTimer();
			} else {
				CloseHandle(pi.hThread);
				process_or_timer = pi.hProcess;

				if( !command.quiet )
					svc->LogEvent( EVENTLOG_INFORMATION_TYPE, format( "Child %d started with PID %d", id, pi.dwProcessId ) );
			}
		}

		void update( Command cmd ) {
			command.quiet = cmd.quiet;
			command.restartDelay = cmd.restartDelay;
		}
	};

	void startTimer(HANDLE h, double delaySeconds) {
		LARGE_INTEGER liDueTime;
		// negative numbers are relative times, times are in 100s of ns -- see SetWaitableTimer MSDN docs
		liDueTime.QuadPart = (LONGLONG)(delaySeconds * -10000000LL);

		if (!SetWaitableTimer(h, &liDueTime, 0, NULL, NULL, 0))
			errorExit( format( "Error in startTimer(): SetWaitableTimer (%d)", GetLastError() ).c_str() );
	}

	virtual void FDBService::OnStart(DWORD argc, LPSTR *argv)
	{
		LogEvent( EVENTLOG_INFORMATION_TYPE, SERVICE_NAME " starting (" FDB_VT_VERSION ")");

		std::string _confpath(GetDefaultConfigFilePath());

		LogEvent( EVENTLOG_INFORMATION_TYPE, format("Default config file at %s", _confpath.c_str() ) );

		// Parse "command line" options
		CSimpleOpt args(argc, argv, g_rgOptions, SO_O_NOERR);

		while (args.Next()) {
			if (args.LastError() == SO_SUCCESS) {
				switch (args.OptionId()) {
					case OPT_CONFFILE:
						_confpath = args.OptionArg();
						break;
				}
			} else {
				// FIXME: log error
				throw (DWORD)1;
			}
		}

		confFile = _confpath;
		LogEvent( EVENTLOG_INFORMATION_TYPE, format("Using config file %s", confFile.c_str() ) );


		// Aquire the mutex for this service. There will be one mutex per config file.
		// If the user installes the executable as more than one service (not likely)
		//  we allow that both can operate so long as they are pointed at different
		//  config files.

		// For now we will not do this check...there is question about whether we need this
		/* std::size_t pos = 0;
		// mutexes cannot have a backslash in their name
		std::string escaped = confFile;
		while( ( pos = escaped.find( "\"", pos ) ) != escaped.npos )
			escaped.replace( pos, 1, "/" );

		HANDLE hMutex = CreateMutex( 
			NULL,                        // default security descriptor
			TRUE,                        // attempt to create with ownership
			format( "Global\\" SERVICE_NAME ".%s", escaped.c_str() ).c_str() );  // object name

		if (hMutex == NULL)
			errorExit( format( "Could not create/aquire global mutex (%s)", escaped.c_str() ).c_str() );
		else
			// In this case ownership on creation flag is ignored. (see MSDN docs)
			if ( GetLastError() == ERROR_ALREADY_EXISTS ) 
				errorExit( "mutex created without ownership");

		LogEvent( EVENTLOG_INFORMATION_TYPE, "instance uniqueness established" ); */

		// Queue the main service function for execution in a worker thread.
		CThreadPool::QueueUserWorkItem(&FDBService::ServiceWorkerThread, this);
	}

	virtual void FDBService::OnStop()
	{
		LogEvent(EVENTLOG_INFORMATION_TYPE, SERVICE_NAME " shutting down");

		serviceStopping = true;
		SetEvent(stoppingEvent);

		if (WaitForSingleObject(stoppedEvent, INFINITE) != WAIT_OBJECT_0)
		{
			// We're exiting, so this will be logged, but an error will not be thrown
			logLastError("OnStop final wait");
		}

		// Log a service stop message to the Application log.
		LogEvent(EVENTLOG_INFORMATION_TYPE, SERVICE_NAME " stop complete");
	}

	virtual void ServiceWorkerThread(void)
	{
		try {
			char confFileDirectory[2048];
			char *fileNameStart;
			if( !GetFullPathName( confFile.c_str(), 2048, confFileDirectory, &fileNameStart ) ) {
				errorExit( format( "get path of conf file (%s)", confFile ).c_str() );
			}

			if( !fileNameStart ) {
				errorExit( format( "file name not present (%s)", confFile ).c_str() );
			}

			// Test file existence
			if( !PathFileExists( confFileDirectory ) ) {
				errorExit( format( "conf file (%s) does not exist", confFileDirectory ).c_str() );
			}

			// null terminate the absolute path string after the directory
			*fileNameStart = 0;
			// confFileDirectory now contains only the parent dir of the conf file

			// FALSE here as "manualReset" means that the timer will go to the unsignaled state once
			//  signalled from a "wait" call.
			HANDLE fileErrorReloadHandle = CreateWaitableTimer(NULL, FALSE, NULL);
			if( fileErrorReloadHandle == INVALID_HANDLE_VALUE ) {
				errorExit( format( "Error creating waitable timer (%d)", GetLastError() ).c_str() );
			}

			HANDLE fileChangeHandle = FindFirstChangeNotification( 
				confFileDirectory,
				FALSE,                           // do not watch the subtree 
				FILE_NOTIFY_CHANGE_LAST_WRITE | FILE_NOTIFY_CHANGE_FILE_NAME );
 
			if( fileChangeHandle == INVALID_HANDLE_VALUE ) {
				errorExit( format( "FindFirstChangeNotification (%s)", confFileDirectory ).c_str() );
			} else {
				LogEvent( EVENTLOG_INFORMATION_TYPE, format( "watching directory %s", confFileDirectory ) );
			}

			loadConf( confFile.c_str() );

			const int subprocessWaitIndexBase = 3;

			while( !serviceStopping ) {
				// The events to be waited on will have this sequence...
				//  The signals and timers are checked in the subprocesses[] map
				//  0  - the shutdown signal
				//  1  - the file change notification
				//  2  - the file load error timer
				// [n] - signals for subprocesses (process termination or restart timer)
				int eventCount = subprocessWaitIndexBase + (int)subprocesses.size();
				HANDLE *events = new HANDLE[eventCount];
				events[0] = stoppingEvent;
				events[1] = fileChangeHandle;
				events[2] = fileErrorReloadHandle;
				for(int i=0; i<subprocesses.size(); i++)
					events[subprocessWaitIndexBase + i] = subprocesses[i]->getHandleToWaitOn();

				// FIXME: Check that eventCount < MAXIMUM_WAIT_OBJECTS, here and/or in loadConf

				// FIXME: Is 'fileChangeHandle' signalling each time around the loop?

				// Wait for any of the events to be signalled
				DWORD signalled = WaitForMultipleObjects( eventCount, events, FALSE, INFINITE );
				delete [] events;

				// Check for error cases (anything other than one of the objects being signalled)
				if( signalled < WAIT_OBJECT_0 || signalled >= WAIT_OBJECT_0 + eventCount ) {
					WriteEventLogEntry( SERVICE_NAME " wait failed", EVENTLOG_ERROR_TYPE );

					// prevent fast spin
					Sleep(2000);
				}
				else if( signalled == WAIT_OBJECT_0 + 0 ) {
					WriteEventLogEntry( SERVICE_NAME " service shutdown signalled", EVENTLOG_INFORMATION_TYPE );
				}
				else if( signalled == WAIT_OBJECT_0 + 1 ) {
					if( !loadConf( confFile.c_str() ) ) {
						// An error was encountered in loading the conf file...set a timer to force a reload
						double retrySeconds = 0.1;
						startTimer( fileErrorReloadHandle, retrySeconds );
						WriteEventLogEntry( format( 
								SERVICE_NAME " scheduling reload in %f seconds", retrySeconds ).c_str(), 
							EVENTLOG_INFORMATION_TYPE );
					} else {
						// The load was a success but we may still have an error-caused reload scheduled.
						//  Cancel any outstanding timers to avoid an uneeded reload of the file.
						CancelWaitableTimer( fileErrorReloadHandle );
					}

					// Reset the signal handling.
					if( !FindNextChangeNotification( fileChangeHandle ) )
					{
						errorExit("FindNextChangeNotification");
					}
				}
				else if( signalled == WAIT_OBJECT_0 + 2 ) {
					WriteEventLogEntry( SERVICE_NAME " attempting configuration reload after error", EVENTLOG_INFORMATION_TYPE );
					if( !loadConf( confFile.c_str() ) ) {
						// An error was encountered in reloading the file after another error
						//  occurred, this should have a longer delay to prevent a spin loop
						startTimer( fileErrorReloadHandle, 1.0 );
					}
				}
				else {
					Subprocess* sp = subprocesses[ signalled - WAIT_OBJECT_0 - subprocessWaitIndexBase ];
					sp->onHandleSignaled();
				}
			}

			for(auto s = subprocesses.begin(); s != subprocesses.end(); ++s)
				delete *s;
			subprocesses.clear();
			id_subprocess.clear();
		} catch(...) {
			LogEvent( EVENTLOG_ERROR_TYPE, SERVICE_NAME " unexpected exception thrown" );
		}

		try {
			LogEvent( EVENTLOG_INFORMATION_TYPE, SERVICE_NAME " signalling stopped" );
			// Signal the stopped event to allow "onStop" to complete
			SetEvent( stoppedEvent );
		} catch(...) {
			LogEvent( EVENTLOG_ERROR_TYPE, SERVICE_NAME " unexpected exception thrown while stopping" );
		}
	}

public:
	// The following method stops the service when ctrl-break is pressed
	void Break()
	{
		LogEvent(EVENTLOG_INFORMATION_TYPE, SERVICE_NAME " shutting down");

		serviceStopping = true;
		SetEvent(stoppingEvent);

		if (WaitForSingleObject(stoppedEvent, INFINITE) != WAIT_OBJECT_0)
		{
			// We're exiting, so this will be logged, but an error will not be thrown
			logLastError("OnStop final wait");
		}

		// Log a service stop message to the Application log.
		LogEvent(EVENTLOG_INFORMATION_TYPE, SERVICE_NAME " stop complete");

		return;
	}

private:
	void findRemovedOrChangedSubprocesses(const CSimpleIni& ini,
			std::vector<Subprocess*> const& subprocesses, 
			std::vector<Subprocess*> & stop_processes,
			std::vector<std::pair<uint16_t, Command>> & start_ids)
	{
		for( auto it = subprocesses.begin(); it != subprocesses.end(); ++it ) {
			Subprocess* sp = *it;
			if( ini.GetSectionSize( sp->command.ssection.c_str() ) == -1) {
				/* Server on this id no longer configured; kill it */
				LogEvent( EVENTLOG_INFORMATION_TYPE, format( "Deconfigured process (ID %d)", sp->id ) );
				stop_processes.push_back( sp );
			} else {
				/* Server still configured; let's check the config */
				Command cmd = makeCommand( ini, sp->command.section, sp->id );
				/* On error we just stop the old process but do not start a new one */
				if( !cmd.valid ) {
					stop_processes.push_back( sp );
				}
				/* The inequality operation only compares the binary path and arguments */
				else if( cmd != sp->command ) {
					/* Config changed; kill the old process, start a new one */
					/* Log only if one of the two are non-quiet */
					if( !cmd.quiet || !sp->command.quiet )
						LogEvent( EVENTLOG_INFORMATION_TYPE, format( "Found new configuration for process (ID %d)", sp->id ) );
					stop_processes.push_back( sp );
					start_ids.push_back( std::make_pair( sp->id, cmd ) );
				} else if( cmd.quiet != sp->command.quiet || cmd.restartDelay != sp->command.restartDelay ) {
					// Update restartDelay and quiet but do not restart running processes
					if( !cmd.quiet || !sp->command.quiet )
						LogEvent( EVENTLOG_INFORMATION_TYPE, format( "Updating process (ID %d)", sp->id ) );
					sp->update( cmd );
				}
			}
		}
	}

	void findAddedSubprocesses(const CSimpleIni& ini, 
		std::unordered_map<uint16_t, Subprocess*> const& id_subprocess,
		std::vector<std::pair<uint16_t, Command>> & start_ids)
	{
		CSimpleIniA::TNamesDepend sections;
		ini.GetAllSections( sections );
		for( auto it = sections.begin(); it != sections.end(); it++ ) {
			if( auto dot = strrchr( it->pItem, '.') ) {
				char* strtol_end;
				int id = strtoul( dot + 1, &strtol_end, 10 );
				if( *strtol_end != '\0' || !(id > 0) ) {
					LogEvent( EVENTLOG_ERROR_TYPE, format( "Found bogus id in %s", it->pItem ) );
				} else {
					if( !id_subprocess.count(id) ) {
						/* Found something we haven't yet started */
						LogEvent( EVENTLOG_INFORMATION_TYPE, format( "Found new process (ID %d)", id ) );
						std::string section( it->pItem, dot - it->pItem );
						Command cmd = makeCommand( ini, section, id );
						if( cmd.valid ) {
							start_ids.push_back( std::make_pair( id, cmd ) );
						} else {
							LogEvent( EVENTLOG_ERROR_TYPE, format(
								"New process (ID %d) does not have a valid specification and will not be started", id ) );
						}
					}
				}
			}
		}
	}

	// Returns 'true' on successful load, 'false' if an error is encountered
	bool loadConf(const char* confpath) {
		LogEvent( EVENTLOG_INFORMATION_TYPE, format( "Loading configuration %s", confpath ) );

		CSimpleIniA ini;
		ini.SetUnicode();

		// Set to a negative code on error.
		SI_Error err = ini.LoadFile( confpath );
		if( err < 0 ) {
			// If the error was file not found, we assume that future changes to the file will
			//  come in as change notifications. This means that we will not poll, we just leave
			//  processes running as-is waiting for the file to reappear.
			if( err == SI_FILE && GetLastError() == ERROR_FILE_NOT_FOUND ) {
				LogEvent( EVENTLOG_ERROR_TYPE, format( "Configuration file `%s' not found on load, waiting for next change", confpath ) );
				return true;
			}
			LogEvent( EVENTLOG_ERROR_TYPE, format( "Configuration file (`%s') load error: %d, %d", confpath, err, GetLastError() ) );
			return false;
		}

		std::vector<Subprocess*> stop_processes;
		std::vector<std::pair<uint16_t, Command>> start_ids;

		/* First check all processes (running or waiting to restart) to be sure that current config 
		   matches saved file state */
		findRemovedOrChangedSubprocesses( ini, subprocesses, stop_processes, start_ids );

		/* We've handled deconfigured servers and changed configs, but now
		   we need to look for newly configured servers */
		findAddedSubprocesses( ini, id_subprocess, start_ids );

		for(auto it = stop_processes.begin(); it != stop_processes.end(); ++it ) {
			removeSubprocess(*it);
			delete *it; // Destructor terminates and waits for termination of actual process (if any)
		}
		for( auto it = start_ids.begin(); it != start_ids.end(); it++ )
			addSubprocess( new Subprocess(this, it->first, it->second) );

		return true;
	}

	const char* getValueMulti(const CSimpleIni& ini, const char* name, ...) {
		const char* ret = NULL;
		const char* section = NULL;
		va_list ap;
		va_start(ap, name);
		while( !ret && (section = va_arg(ap, const char *) ) ) {
			ret = ini.GetValue( section, name, NULL );
		}
		va_end(ap);
		return ret;
	}

	Command makeCommand(const CSimpleIni& ini, std::string section, uint16_t id) {
		std::string ssection = format("%s.%d", section.c_str(), id);
		Command result;

		CSimpleIniA::TNamesDepend keys, skeys, gkeys;

		ini.GetAllKeys(section.c_str(), keys);
		ini.GetAllKeys(ssection.c_str(), skeys);
		ini.GetAllKeys("general", gkeys);

		keys.splice(keys.end(), skeys, skeys.begin(), skeys.end());
		keys.splice(keys.end(), gkeys, gkeys.begin(), gkeys.end());
		keys.sort(CSimpleIniA::Entry::KeyOrder());
		keys.unique( [](const CSimpleIniA::Entry& lhs, const CSimpleIniA::Entry& rhs) -> bool {
				return !CSimpleIniA::Entry::KeyOrder()(lhs, rhs);
			} );

		const char* rd = getValueMulti(ini, "restart_delay", ssection.c_str(), section.c_str(), "general", "fdbmonitor", NULL);
		if(!rd) {
			LogEvent( EVENTLOG_ERROR_TYPE, format( "Unable to resolve restart delay for %s\n", ssection.c_str() ) );
			return result;
		}

		char* endptr;
		result.restartDelay = strtoul(rd, &endptr, 10);
		if (*endptr != '\0') {
			LogEvent( EVENTLOG_ERROR_TYPE, format( "Unable to parse restart delay for %s\n", ssection.c_str() ) );
			return result;
		}

		const char* q = getValueMulti(ini, "disable_lifecycle_logging", ssection.c_str(), section.c_str(), "general", NULL);
		if( q && !strcmp(q, "true") )
			result.quiet = true;

		const char* binary = getValueMulti(ini, "command", ssection.c_str(), section.c_str(), "general", NULL);
		if( !binary ) {
			LogEvent( EVENTLOG_ERROR_TYPE, format( "Unable to resolve command for %s.%d\n", section.c_str(), id ) );
			return result;
		}
		result.binary = binary;
		result.args = quote(binary);

		const char* id_s = ssection.c_str() + strlen( section.c_str() ) + 1;

		for( auto i : keys ) {
			if( !strcmp(i.pItem, "command") ||
				!strcmp(i.pItem, "restart_delay") || 
				!strcmp(i.pItem, "disable_lifecycle_logging"))
			{
				continue;
			}

			std::string opt = getValueMulti( ini, i.pItem, ssection.c_str(), section.c_str(), "general", NULL );

			std::size_t pos = 0;
			while( (pos = opt.find("$ID", pos)) != opt.npos )
				opt.replace( pos, 3, id_s, strlen(id_s) );

			pos = 0;
			std::string pid_s = format("%d", GetCurrentProcessId());
			while( (pos = opt.find("$PID", pos)) != opt.npos )
				opt.replace( pos, 4, pid_s.c_str(), pid_s.size() );

			result.args += std::string(" --") + i.pItem + "=" + quote(opt);
		}

		result.section = section;
		result.ssection = ssection;
		result.valid = true;
		return result;
	}

	static std::string quote( std::string const& s ) {
		std::string q;
		/* Replace every backslash whose next non-backslash character is either the
		end of the string or a double-quote by two backslashes */
		for( int i = 0; i < s.size(); i++ ) {
			q.append( 1, s[i] );
			if( s[i] == '\\' ) {
				int add = true;
				for( int j = i + 1; j < s.size(); j++ )  {
					// If any character other than backslash is encountered, do not duplicate.
					// Start with "true" so hitting the end of the string keep "add" true.
					if( s[j] != '\\' ) {
						add = false;
						break;
					}
				}
				if( add )
					q.append( 1, '\\' );
			}
		}

		/* Replace every double-quote in the string by backslash double-quote */
		std::size_t pos = 0;
		while( ( pos = q.find( "\"", pos ) ) != q.npos )
			q.replace( pos, 1, "\\\"" );
		return "\"" + q + "\"";
	}

	///////////////
	// Error handling, etc.
	///////////////
	void errorExit(const char *context) {
		logLastError(context);
		ExitProcess(GetLastError());
	}

	void LogEvent(int wType, std::string message) {
		WriteEventLogEntry( message.c_str(), wType );
		writeLogLine( message );
	}

	void logLastError(const char *context) {
		LogEvent( EVENTLOG_ERROR_TYPE, format( "%s failed (%d)", context, GetLastError() ) );
	}

	std::string confFile;
	bool serviceStopping;
	HANDLE stoppingEvent;
	HANDLE stoppedEvent;
	HANDLE childJob;

	std::unordered_map<uint16_t, Subprocess*> id_subprocess;
	std::vector<Subprocess*> subprocesses;

	void addSubprocess( Subprocess* newsp ) {
		newsp->subprocess_index = subprocesses.size();
		subprocesses.push_back(newsp);
		id_subprocess[ newsp->id ] = newsp;
	}
	void removeSubprocess( Subprocess* sp ) {
		subprocesses.back()->subprocess_index = sp->subprocess_index;
		subprocesses[sp->subprocess_index] = subprocesses.back();
		subprocesses.pop_back();
		id_subprocess.erase( sp->id );
	}
};

static FDBService*	staticService = NULL;

bool consoleHandler(int signal)
{
	// Break from the program if ctrl-c is pressed
	if ((signal == CTRL_C_EVENT)	&&
		(staticService)				)
	{
		staticService->Break();
	}

	return true;
}

void print_usage(const char *name) {
	printf(
		"FoundationDB Process Monitor " SERVICE_NAME " (v" FDB_VT_VERSION ")\n"
		"Usage: %s [OPTIONS]\n"
		"\n"
		"  -f --foreground Run the process in the foreground and not as a service\n"
		"  -l --logging    Enable logging\n"
		"  -h, --help      Display this help and exit.\n", name);
}

int main(DWORD argc, LPCSTR *argv) {
	_set_FMA3_enable(0); // Workaround for VS 2013 code generation bug. See https://connect.microsoft.com/VisualStudio/feedback/details/811093/visual-studio-2013-rtm-c-x64-code-generation-bug-for-avx2-instructions

	int		status = 0;
	bool	bBackground, bRun;

	// Initialize variables
	bBackground = true;
	bRun = true;

	// Check if argument is specified to run in foreground
	for (DWORD loop = 1; loop < argc; loop++)
	{
		// Ignore undefined or non-options
		if ((argv[loop] == NULL) ||
			(argv[loop][0] == '\0'))
		{

		}

		// Check, if foreground option
		else if ((!_strnicmp("-f", argv[loop], 2)) ||
			(!_strnicmp("--f", argv[loop], 3)))
		{
			bBackground = false;
		}

		// Check, if logging is enabled
		else if ((!strnicmp("-l", argv[loop], 2)) ||
			(!_strnicmp("--l", argv[loop], 3)))
		{
			logging = true;
		}

		// Check, if help is requested
		else if ((!strnicmp("-h", argv[loop], 2)) ||
			(!_strnicmp("--h", argv[loop], 3)))
		{
			print_usage(argv[0]);

			// Disable execution, if displaying help
			bRun = false;
		}
	}

	// Only run, if run is still enabled
	if (bRun)
	try {
		// the "start arguments" to the service are passed to the OnStart call, not to here

		if( logging ) {
			// Determine the default conf path
			char programData[2048];
			if( !GetEnvironmentVariable( "ALLUSERSPROFILE", programData, 2048 ) ) {
				throw GetLastError();
			}
			if( !CreateDirectory( format( "%s\\foundationdb", programData ).c_str(), NULL ) ) {
				if( GetLastError() != ERROR_ALREADY_EXISTS )
					throw GetLastError();
			}
			logFile.open(programData + std::string("\\foundationdb\\servicelog.txt"));
		}

		FDBService service(SERVICE_NAME);

		// If not background, run the service in the foreground
		if (!bBackground)
		{
			// Store the service class
			staticService = &service;

			// Enable the ctrl handler
			SetConsoleCtrlHandler((PHANDLER_ROUTINE)consoleHandler, TRUE);

			// Run the service
			if (!service.Run())
			{
				fprintf(stderr, "Service failed to run w/err 0x%08lx\n", GetLastError());
				status++;
			}
		}

		// Otherwise, run the service within the background using the service manager
		else if (!CServiceBase::Run(service)) {
			fprintf(stderr, "Service failed to run w/err 0x%08lx\n", GetLastError());
			status++;
		}

		else if( logging ) {
		}
	} catch( DWORD errno ) {
		writeLogLine( format( "Service threw exception 0x%08lx\n", errno ) );
		fprintf(stderr, "Service failed to run w/err 0x%08lx\n", errno);
		status++;
	}
	catch (...) {
		writeLogLine( format( "Service failed with unexpected error (last error: %d)\n", GetLastError() ) );
		fprintf(stderr, "Service failed with unexpected error (last error: %d)\n", GetLastError());
		status++;
	}

	return status;
}