1 files changed, 530 insertions, 0 deletions
diff --git a/lib/server/Daemon.cpp b/lib/server/Daemon.cpp
new file mode 100755
index 00000000..31997fb6
--- /dev/null
+++ b/lib/server/Daemon.cpp
@@ -0,0 +1,530 @@
+// --------------------------------------------------------------------------
+//
+// File
+//		Name:    Daemon.cpp
+//		Purpose: Basic daemon functionality
+//		Created: 2003/07/29
+//
+// --------------------------------------------------------------------------
+
+#include "Box.h"
+
+#include <stdio.h>
+#include <unistd.h>
+#include <syslog.h>
+#include <signal.h>
+#include <string.h>
+#include <stdarg.h>
+
+#include "Daemon.h"
+#include "Configuration.h"
+#include "ServerException.h"
+#include "Guards.h"
+#include "UnixUser.h"
+
+#include "MemLeakFindOn.h"
+
+Daemon *Daemon::spDaemon = 0;
+
+
+// --------------------------------------------------------------------------
+//
+// Function
+//		Name:    Daemon::Daemon()
+//		Purpose: Constructor
+//		Created: 2003/07/29
+//
+// --------------------------------------------------------------------------
+Daemon::Daemon()
+	: mpConfiguration(0),
+	  mReloadConfigWanted(false),
+	  mTerminateWanted(false)
+{
+	if(spDaemon != 0)
+	{
+		THROW_EXCEPTION(ServerException, AlreadyDaemonConstructed)
+	}
+	spDaemon = this;
+	
+	// And in debug builds, we'll switch on assert failure logging to syslog
+	ASSERT_FAILS_TO_SYSLOG_ON
+	// And trace goes to syslog too
+	TRACE_TO_SYSLOG(true)
+}
+
+// --------------------------------------------------------------------------
+//
+// Function
+//		Name:    Daemon::~Daemon()
+//		Purpose: Destructor
+//		Created: 2003/07/29
+//
+// --------------------------------------------------------------------------
+Daemon::~Daemon()
+{
+	if(mpConfiguration)
+	{
+		delete mpConfiguration;
+		mpConfiguration = 0;
+	}
+}
+
+// --------------------------------------------------------------------------
+//
+// Function
+//		Name:    Daemon::Main(const char *, int, const char *[])
+//		Purpose: Starts the daemon off -- equivalent of C main() function
+//		Created: 2003/07/29
+//
+// --------------------------------------------------------------------------
+int Daemon::Main(const char *DefaultConfigFile, int argc, const char *argv[])
+{
+	// Banner (optional)
+	{
+		const char *banner = DaemonBanner();
+		if(banner != 0)
+		{
+			printf("%s", banner);
+		}
+	}
+
+	std::string pidFileName;
+	const char *configfile = 0;
+
+	try
+	{
+		// Find filename of config file
+		configfile = DefaultConfigFile;
+		if(argc >= 2)
+		{
+			// First argument is config file, or it's -c and the next arg is the config file
+			if(::strcmp(argv[1], "-c") == 0 && argc >= 3)
+			{
+				configfile = argv[2];
+			}
+			else
+			{
+				configfile = argv[1];
+			}
+		}
+		
+		// Test mode with no daemonisation?
+		bool asDaemon = true;
+		if(argc >= 3)
+		{
+			if(::strcmp(argv[2], "SINGLEPROCESS") == 0)
+			{
+				asDaemon = false;
+			}
+		}
+
+		// Load the configuration file.
+		std::string errors;
+		std::auto_ptr<Configuration> pconfig = Configuration::LoadAndVerify(configfile, GetConfigVerify(), errors);
+
+		// Got errors?
+		if(pconfig.get() == 0 || !errors.empty())
+		{
+			// Tell user about errors
+			fprintf(stderr, "%s: Errors in config file %s:\n%s", DaemonName(), configfile, errors.c_str());
+			// And give up
+			return 1;
+		}
+		
+		// Store configuration
+		mpConfiguration = pconfig.release();
+		
+		// Server configuration
+		const Configuration &serverConfig(mpConfiguration->GetSubConfiguration("Server"));
+		
+		// Let the derived class have a go at setting up stuff in the initial process
+		SetupInInitialProcess();
+		
+		// Set signal handler
+		if(::signal(SIGHUP, SignalHandler) == SIG_ERR || ::signal(SIGTERM, SignalHandler) == SIG_ERR)
+		{
+			THROW_EXCEPTION(ServerException, DaemoniseFailed)
+		}
+		
+		// Open PID file for writing
+		pidFileName = serverConfig.GetKeyValue("PidFile");
+		FileHandleGuard<(O_WRONLY | O_CREAT | O_TRUNC), (S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH)> pidFile(pidFileName.c_str());
+		
+		// Handle changing to a different user
+		if(serverConfig.KeyExists("User"))
+		{
+			// Config file specifies an user -- look up
+			UnixUser daemonUser(serverConfig.GetKeyValue("User").c_str());
+			
+			// Change the owner on the PID file, so it can be deleted properly on termination
+			if(::fchown(pidFile, daemonUser.GetUID(), daemonUser.GetGID()) != 0)
+			{
+				THROW_EXCEPTION(ServerException, CouldNotChangePIDFileOwner)
+			}
+			
+			// Change the process ID
+			daemonUser.ChangeProcessUser();
+		}
+	
+		if(asDaemon)
+		{
+			// Let's go... Daemonise...
+			switch(::fork())
+			{
+			case -1:
+				// error
+				THROW_EXCEPTION(ServerException, DaemoniseFailed)
+				break;
+
+			default:
+				// parent
+				_exit(0);
+				return 0;
+				break;
+
+			case 0:
+				// child
+				break;
+			}
+
+			// In child
+
+			// Set new session
+			if(::setsid() == -1)
+			{
+				::syslog(LOG_ERR, "can't setsid");
+				THROW_EXCEPTION(ServerException, DaemoniseFailed)
+			}
+
+			// Fork again...
+			switch(::fork())
+			{
+			case -1:
+				// error
+				THROW_EXCEPTION(ServerException, DaemoniseFailed)
+				break;
+
+			default:
+				// parent
+				_exit(0);
+				return 0;
+				break;
+
+			case 0:
+				// child
+				break;
+			}
+		}
+
+		// open the log
+		::openlog(DaemonName(), LOG_PID, LOG_LOCAL6);
+		// Log the start message
+		::syslog(LOG_INFO, "Starting daemon (config: %s) (version " BOX_VERSION ")", configfile);
+
+		// Write PID to file
+		char pid[32];
+		int pidsize = sprintf(pid, "%d", (int)getpid());
+		if(::write(pidFile, pid, pidsize) != pidsize)
+		{
+			::syslog(LOG_ERR, "can't write pid file");
+			THROW_EXCEPTION(ServerException, DaemoniseFailed)
+		}
+		
+		// Set up memory leak reporting
+		#ifdef BOX_MEMORY_LEAK_TESTING
+		{
+			char filename[256];
+			sprintf(filename, "%s.memleaks", DaemonName());
+			memleakfinder_setup_exit_report(filename, DaemonName());
+		}
+		#endif // BOX_MEMORY_LEAK_TESTING
+	
+		if(asDaemon)
+		{
+			// Close standard streams
+			::close(0);
+			::close(1);
+			::close(2);
+			
+			// Open and redirect them into /dev/null
+			int devnull = ::open(PLATFORM_DEV_NULL, O_RDWR, 0);
+			if(devnull == -1)
+			{
+				THROW_EXCEPTION(CommonException, OSFileError);
+			}
+			// Then duplicate them to all three handles
+			if(devnull != 0) dup2(devnull, 0);
+			if(devnull != 1) dup2(devnull, 1);
+			if(devnull != 2) dup2(devnull, 2);
+			// Close the original handle if it was opened above the std* range
+			if(devnull > 2)
+			{
+				::close(devnull);
+			}
+			
+			// And definately don't try and send anything to those file descriptors
+			// -- this has in the past sent text to something which isn't expecting it.
+			TRACE_TO_STDOUT(false);
+		}		
+	}
+	catch(BoxException &e)
+	{
+		fprintf(stderr, "%s: exception %s (%d/%d)\n", DaemonName(), e.what(), e.GetType(), e.GetSubType());
+		return 1;
+	}
+	catch(std::exception &e)
+	{
+		fprintf(stderr, "%s: exception %s\n", DaemonName(), e.what());
+		return 1;
+	}
+	catch(...)
+	{
+		fprintf(stderr, "%s: unknown exception\n", DaemonName());
+		return 1;
+	}
+	
+	// Main Daemon running
+	try
+	{
+		while(!mTerminateWanted)
+		{
+			Run();
+			
+			if(mReloadConfigWanted && !mTerminateWanted)
+			{
+				// Need to reload that config file...
+				::syslog(LOG_INFO, "Reloading configuration (config: %s)", configfile);
+				std::string errors;
+				std::auto_ptr<Configuration> pconfig = Configuration::LoadAndVerify(configfile, GetConfigVerify(), errors);
+
+				// Got errors?
+				if(pconfig.get() == 0 || !errors.empty())
+				{
+					// Tell user about errors
+					::syslog(LOG_ERR, "Errors in config file %s:\n%s", configfile, errors.c_str());
+					// And give up
+					return 1;
+				}
+				
+				// delete old configuration
+				delete mpConfiguration;
+				mpConfiguration = 0;
+
+				// Store configuration
+				mpConfiguration = pconfig.release();
+				
+				// Stop being marked for loading config again
+				mReloadConfigWanted = false;
+			}
+		}
+		
+		// Delete the PID file
+		::unlink(pidFileName.c_str());
+		
+		// Log
+		::syslog(LOG_INFO, "Terminating daemon");
+	}
+	catch(BoxException &e)
+	{
+		::syslog(LOG_ERR, "exception %s (%d/%d) -- terminating", e.what(), e.GetType(), e.GetSubType());
+		return 1;
+	}
+	catch(std::exception &e)
+	{
+		::syslog(LOG_ERR, "exception %s -- terminating", e.what());
+		return 1;
+	}
+	catch(...)
+	{
+		::syslog(LOG_ERR, "unknown exception -- terminating");
+		return 1;
+	}
+	
+	return 0;
+}
+
+// --------------------------------------------------------------------------
+//
+// Function
+//		Name:    Daemon::EnterChild()
+//		Purpose: Sets up for a child task of the main server. Call just after fork()
+//		Created: 2003/07/31
+//
+// --------------------------------------------------------------------------
+void Daemon::EnterChild()
+{
+	// Unset signal handlers
+	::signal(SIGHUP, SIG_DFL);
+	::signal(SIGTERM, SIG_DFL);
+}
+
+
+// --------------------------------------------------------------------------
+//
+// Function
+//		Name:    Daemon::SignalHandler(int)
+//		Purpose: Signal handler
+//		Created: 2003/07/29
+//
+// --------------------------------------------------------------------------
+void Daemon::SignalHandler(int sigraised)
+{
+	if(spDaemon != 0)
+	{
+		switch(sigraised)
+		{
+		case SIGHUP:
+			spDaemon->mReloadConfigWanted = true;
+			break;
+			
+		case SIGTERM:
+			spDaemon->mTerminateWanted = true;
+			break;
+		
+		default:
+			break;
+		}
+	}
+}
+
+// --------------------------------------------------------------------------
+//
+// Function
+//		Name:    Daemon::DaemonName() 
+//		Purpose: Returns name of the daemon
+//		Created: 2003/07/29
+//
+// --------------------------------------------------------------------------
+const char *Daemon::DaemonName() const
+{
+	return "generic-daemon";
+}
+
+
+// --------------------------------------------------------------------------
+//
+// Function
+//		Name:    Daemon::DaemonBanner()
+//		Purpose: Returns the text banner for this daemon's startup
+//		Created: 1/1/04
+//
+// --------------------------------------------------------------------------
+const char *Daemon::DaemonBanner() const
+{
+	return 0;
+}
+
+
+// --------------------------------------------------------------------------
+//
+// Function
+//		Name:    Daemon::Run()
+//		Purpose: Main run function after basic Daemon initialisation
+//		Created: 2003/07/29
+//
+// --------------------------------------------------------------------------
+void Daemon::Run()
+{
+	while(!StopRun())
+	{
+		::sleep(10);
+	}
+}
+
+
+// --------------------------------------------------------------------------
+//
+// Function
+//		Name:    Daemon::GetConfigVerify()
+//		Purpose: Returns the configuration file verification structure for this daemon
+//		Created: 2003/07/29
+//
+// --------------------------------------------------------------------------
+const ConfigurationVerify *Daemon::GetConfigVerify() const
+{
+	static ConfigurationVerifyKey verifyserverkeys[] = 
+	{
+		DAEMON_VERIFY_SERVER_KEYS
+	};
+
+	static ConfigurationVerify verifyserver[] = 
+	{
+		{
+			"Server",
+			0,
+			verifyserverkeys,
+			ConfigTest_Exists | ConfigTest_LastEntry,
+			0
+		}
+	};
+
+	static ConfigurationVerify verify =
+	{
+		"root",
+		verifyserver,
+		0,
+		ConfigTest_Exists | ConfigTest_LastEntry,
+		0
+	};
+
+	return &verify;
+}
+
+
+// --------------------------------------------------------------------------
+//
+// Function
+//		Name:    Daemon::GetConfiguration()
+//		Purpose: Returns the daemon configuration object
+//		Created: 2003/07/29
+//
+// --------------------------------------------------------------------------
+const Configuration &Daemon::GetConfiguration() const
+{
+	if(mpConfiguration == 0)
+	{
+		// Shouldn't get anywhere near this if a configuration file can't be loaded
+		THROW_EXCEPTION(ServerException, Internal)
+	}
+	
+	return *mpConfiguration;
+}
+
+
+// --------------------------------------------------------------------------
+//
+// Function
+//		Name:    Daemon::SetupInInitialProcess()
+//		Purpose: A chance for the daemon to do something initial setting up in the process which
+//				 initiates everything, and after the configuration file has been read and verified.
+//		Created: 2003/08/20
+//
+// --------------------------------------------------------------------------
+void Daemon::SetupInInitialProcess()
+{
+	// Base class doesn't do anything.
+}
+
+
+void Daemon::SetProcessTitle(const char *format, ...)
+{
+	// On OpenBSD, setproctitle() sets the process title to imagename: <text> (imagename)
+	// -- make sure other platforms include the image name somewhere so ps listings give
+	// useful information.
+
+#ifdef PLATFORM_HAVE_setproctitle
+	// optional arguments
+	va_list args;
+	va_start(args, format);
+
+	// Make the string
+	char title[256];
+	::vsnprintf(title, sizeof(title), format, args);
+	
+	// Set process title
+	::setproctitle("%s", title);
+	
+#endif // PLATFORM_HAVE_setproctitle
+}
+
+