scalestack::kernel::core Class Reference

#include <core.h>

Inheritance diagram for scalestack::kernel::core:

Public Member Functions
	core (void)
	~core ()
void	parse_arguments (int argument_count, const char **arguments)
void	parse_file (const std::string &filename)
void	add_module_option_value (const std::string &module_name, const std::string &option_name, const std::string &value)
void	set_signal_handlers (void)
void	handle_signal (int signal_number)
module &	get_or_add_module (const std::string &name)
module &	get_module (const std::string &name) const
size_t	get_module_count (void) const
module *	begin_module (void)
module *	next_module (void)
void	add_service (const std::string &name, service *service)
service *	remove_service (const std::string &name)
service &	get_service (const std::string &name) const
size_t	get_service_count (void) const
void	add_log (const std::string &name, log *log)
log *	remove_log (const std::string &name)
log &	get_log (const std::string &name) const
size_t	get_log_count (void) const
void	run (void)
void	shutdown (void)
Private Types
typedef std::vector< std::string >	files
typedef std::vector< std::string >	paths
typedef std::vector< module * >	modules
typedef std::map< std::string, std::string >	aliases
typedef std::map< std::string, service * >	services
typedef std::map< std::string, log * >	logs
Private Member Functions
	core (const core &)
core &	operator= (const core &)
void	_parse_argument (std::string argument)
const std::string &	_get_alias (const std::string &name) const
module *	_get_module (const std::string &name) const
void	_notify (void)
void	_set_fatal_message (const char *format, std::va_list arguments) const
void	_log_message (log::level log_level, const char *format, std::va_list arguments) const
void	_log (log::level log_level, const char context, const char format, std::va_list arguments) const
void	_print_help (void)
void	_print_config (void)
Private Attributes
bool	_need_help
bool	_need_config
bool	_shutdown_request
bool	_iterator_on_modules
int	_notify_pipe [2]
files	_open_files
paths	_paths
modules	_modules
modules	_new_modules
modules::iterator	_module_iterator
aliases	_aliases
services	_services
logs	_logs
Friends
class	module

Detailed Description

This class is the central part of the kernel and is responsible for managing modules, services, and kernel logs. This and other kernel classes should be kept as minimal as possible and instead prefer pushing functionality into modules.

Definition at line 49 of file core.h.

Member Typedef Documentation

typedef std::vector<std::string> scalestack::kernel::core::files [private]

Definition at line 343 of file core.h.

typedef std::vector<std::string> scalestack::kernel::core::paths [private]

Definition at line 344 of file core.h.

typedef std::vector<module*> scalestack::kernel::core::modules [private]

Definition at line 345 of file core.h.

typedef std::map<std::string, std::string> scalestack::kernel::core::aliases [private]

Definition at line 346 of file core.h.

typedef std::map<std::string, service*> scalestack::kernel::core::services [private]

Definition at line 347 of file core.h.

typedef std::map<std::string, log*> scalestack::kernel::core::logs [private]

Definition at line 348 of file core.h.

Constructor & Destructor Documentation

scalestack::kernel::core::core ( void )

Initialize all data members and add a log_console object to the list of logs.

Definition at line 73 of file core.cc.

scalestack::kernel::core::~core ( )

Ensure all modules are properly cleaned up and generate error messages if there are leftover services or logs.

Definition at line 101 of file core.cc.

scalestack::kernel::core::core ( const core & ) [private]

Don't allow copying of objects.

Member Function Documentation

void scalestack::kernel::core::parse_arguments	(	int	argument_count,
		const char **	arguments
	)

Parse arguments, most likely from the main() function arguments.

Parameters:

`[in]`	argument_count	Argument count.
`[in]`	arguments	Array of argument values.

Definition at line 139 of file core.cc.

void scalestack::kernel::core::parse_file ( const std::string & filename )

Parse arguments from a file. The options in the file should be formatted the same as the command line options with one option per line. Comments start with a '#', and all empty lines are ignored.

Parameters:

[in] filename Name of the file to parse.

Definition at line 174 of file core.cc.

void scalestack::kernel::core::add_module_option_value	(	const std::string &	module_name,
		const std::string &	option_name,
		const std::string &	value
	)

Add an option value for a module. If a value already exists, the old value is overwritten. Options can be of the form:

module_name - Add the module name to be loaded. module_name=value - Add a module alias from module_name to value. module_name.option_name=value - Set a module option.

Parameters:

`[in]`	module_name	Name of the module to add the option for.
`[in]`	option_name	Name of the option.
`[in]`	value	Value of the option.

Definition at line 226 of file core.cc.

void scalestack::kernel::core::set_signal_handlers ( void )

Set common signal handlers. Calling applications can either use this for convenience or handle their own signals. If applications need more than one core object, they cannot use this function and must handle their own signals, calling handle_signal() as needed. SIGPIPE is set to be ignored, and the following signals are set to call handle_signal(): SIGHUP, SIGINT, SIGQUIT, SIGTERM, SIGUSR1, and SIGUSR2.

Definition at line 300 of file core.cc.

void scalestack::kernel::core::handle_signal ( int signal_number )

Handle signals received by application signal handlers. This currently process SIGINT, SIGQUIT, and SIGTERM as shutdown requests. This can be used by applications that wish to handle their own signals.

Parameters:

[in] signal_number Signal that was caught and needs to be handled.

Definition at line 340 of file core.cc.

module & scalestack::kernel::core::get_or_add_module ( const std::string & name )

Get a module that has been added to the core, or add one if a module by that name doesn't exist.

Parameters:

[in] name Name of the module to add. This is used in constructing the path of the module to load. Name comparisons are case insensitive.

Returns:: The module that was added.

Definition at line 352 of file core.cc.

module & scalestack::kernel::core::get_module ( const std::string & name ) const

Get a module that has been added to the core.

Parameters:

[in] name Name of the module to look for. This is used to check both the name and alias list. Name comparisons are case insensitive.

Returns:: The module that was found.

Definition at line 366 of file core.cc.

size_t scalestack::kernel::core::get_module_count ( void ) const

Get a count of the number of modules in the core.

Definition at line 377 of file core.cc.

module * scalestack::kernel::core::begin_module ( void )

Reset the module iterator to the beginning and return first module. This should be called first before iterating through all modules. The most common way to use this interface is:

   for (module* module = core.begin_module();
        module != NULL;
        module = core.next_module())
   {
     // Do something with module here.
   }

Returns:: First module or NULL if there are no modules.

Definition at line 382 of file core.cc.

module * scalestack::kernel::core::next_module ( void )

Get the next module while iterating, see begin_module() for usage details.

Returns:: Next module or NULL if at the end of the list.

Definition at line 389 of file core.cc.

void scalestack::kernel::core::add_service	(	const std::string &	name,
		service *	service
	)

Add a service object for the given name. If a service by that name already exists, this will throw an exception.

Parameters:

`[in]`	name	Name of the service to add.
`[in]`	service	The service object to add.

Definition at line 403 of file core.cc.

service * scalestack::kernel::core::remove_service ( const std::string & name )

Remove a service object for the given name.

Parameters:

[in] name Name of the service to remove.

Returns:: The service object that was removed.

Definition at line 413 of file core.cc.

service & scalestack::kernel::core::get_service ( const std::string & name ) const

Get a service object for the given name.

Parameters:

[in] name Name of the service to get.

Returns:: The service object that was requested.

Definition at line 425 of file core.cc.

size_t scalestack::kernel::core::get_service_count ( void ) const

Get a count of the number of services that have been added.

Definition at line 434 of file core.cc.

void scalestack::kernel::core::add_log	(	const std::string &	name,
		log *	log
	)

Add a log object for the given name. If a log by that name already exists, this will throw an exception.

Parameters:

`[in]`	name	Name of the log to add.
`[in]`	log	The log object to add.

Definition at line 439 of file core.cc.

log * scalestack::kernel::core::remove_log ( const std::string & name )

Remove a log object for the given name.

Parameters:

[in] name Name of the log to remove.

Returns:: The log object that was removed.

Definition at line 449 of file core.cc.

log & scalestack::kernel::core::get_log ( const std::string & name ) const

Get a log object for the given name.

Parameters:

[in] name Name of the log to get.

Returns:: The log object that was requested.

Definition at line 461 of file core.cc.

size_t scalestack::kernel::core::get_log_count ( void ) const

Get a count of the number of logs that have been added.

Definition at line 470 of file core.cc.

void scalestack::kernel::core::run ( void )

This is the main loop of the core and will continue running until a shutdown request is received.

Definition at line 475 of file core.cc.

void scalestack::kernel::core::shutdown ( void )

Notify the kernel core that it should start the shutdown process. This is usually called from signal handlers or modules providing administrative functions.

Definition at line 526 of file core.cc.

core& scalestack::kernel::core::operator= ( const core & ) [private]

Don't allow assignment of objects.

void scalestack::kernel::core::_parse_argument ( std::string argument ) [private]

Parse a single argument from any source. The format is module[.option][=value], and the parsed value is passed into add_module_option_value().

Parameters:

[in] argument Argment to parse.

Definition at line 537 of file core.cc.

const string & scalestack::kernel::core::_get_alias ( const std::string & name ) const [private]

Resolve module names using the alias map.

Parameters:

[in] name Name to look up in alias map.

Returns:: Alias if found, or original name that was passed in.

Definition at line 602 of file core.cc.

module * scalestack::kernel::core::_get_module ( const std::string & name ) const [private]

Get a module that has been added to the core, this is only used internally. This behaves just like get_module() (and is used by that method) but does not throw exceptions when the module is not found.

Definition at line 615 of file core.cc.

void scalestack::kernel::core::_notify ( void ) [private]

Notify the main loop that it should wake up and process pending events.

Definition at line 641 of file core.cc.

void scalestack::kernel::core::_set_fatal_message	(	const char *	format,
		std::va_list	arguments
	)			const `[private, virtual]`

Set a fatal message as the error string. This is declared const so other const methods can call it.

Parameters:

`[in]`	format	Message format string.
`[in]`	arguments	Argument list for formatted message.

Implements scalestack::kernel::logger.

Definition at line 647 of file core.cc.

void scalestack::kernel::core::_log_message	(	log::level	log_level,
		const char *	format,
		std::va_list	arguments
	)			const `[private, virtual]`

Log a core message. This is declared const so other const methods can call it.

Parameters:

`[in]`	log_level	Log level for this message.
`[in]`	format	Message format string.
`[in]`	arguments	Argument list for formatted message.

Implements scalestack::kernel::logger.

Definition at line 654 of file core.cc.

void scalestack::kernel::core::_log	(	log::level	log_level,
		const char *	context,
		const char *	format,
		std::va_list	arguments
	)			const `[private]`

Send a log message to all configured logs. This is declared const so other const methods can call it.

Parameters:

`[in]`	log_level	Log level for this message.
`[in]`	context	Context string for this message.
`[in]`	format	Message format string.
`[in]`	arguments	Argument list for formatted message.