eloop.h File Reference

Event loop. More...

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Defines
#define	ELOOP_ALL_CTX   (void *) -1
	eloop_cancel_timeout() magic number to match all timeouts
Typedefs
typedef void(*	eloop_sock_handler )(int sock, void *eloop_ctx, void *sock_ctx)
	eloop socket event callback type
typedef void(*	eloop_event_handler )(void *eloop_data, void *user_ctx)
	eloop generic event callback type
typedef void(*	eloop_timeout_handler )(void *eloop_data, void *user_ctx)
	eloop timeout event callback type
typedef void(*	eloop_signal_handler )(int sig, void *eloop_ctx, void *signal_ctx)
	eloop signal event callback type
Enumerations
enum	eloop_event_type { EVENT_TYPE_READ = 0, EVENT_TYPE_WRITE, EVENT_TYPE_EXCEPTION }
	eloop socket event type for eloop_register_sock() More...
Functions
int	eloop_init (void *user_data)
	Initialize global event loop data.
int	eloop_register_read_sock (int sock, eloop_sock_handler handler, void *eloop_data, void *user_data)
	Register handler for read events.
void	eloop_unregister_read_sock (int sock)
	Unregister handler for read events.
int	eloop_register_sock (int sock, eloop_event_type type, eloop_sock_handler handler, void *eloop_data, void *user_data)
	Register handler for socket events.
void	eloop_unregister_sock (int sock, eloop_event_type type)
	Unregister handler for socket events.
int	eloop_register_event (void *event, size_t event_size, eloop_event_handler handler, void *eloop_data, void *user_data)
	Register handler for generic events.
void	eloop_unregister_event (void *event, size_t event_size)
	Unregister handler for a generic event.
int	eloop_register_timeout (unsigned int secs, unsigned int usecs, eloop_timeout_handler handler, void *eloop_data, void *user_data)
	Register timeout.
int	eloop_cancel_timeout (eloop_timeout_handler handler, void *eloop_data, void *user_data)
	Cancel timeouts.
int	eloop_register_signal (int sig, eloop_signal_handler handler, void *user_data)
	Register handler for signals.
int	eloop_register_signal_terminate (eloop_signal_handler handler, void *user_data)
	Register handler for terminate signals.
int	eloop_register_signal_reconfig (eloop_signal_handler handler, void *user_data)
	Register handler for reconfig signals.
void	eloop_run (void)
	Start the event loop.
void	eloop_terminate (void)
	Terminate event loop.
void	eloop_destroy (void)
	Free any resources allocated for the event loop.
int	eloop_terminated (void)
	Check whether event loop has been terminated.
void	eloop_wait_for_read_sock (int sock)
	Wait for a single reader.
void *	eloop_get_user_data (void)
	Get global user data.

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Detailed Description

Event loop.

Copyright

Copyright (c) 2002-2006, Jouni Malinen <[email protected]>

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License version 2 as published by the Free Software Foundation.

Alternatively, this software may be distributed under the terms of BSD license.

See README and COPYING for more details.

This file defines an event loop interface that supports processing events from registered timeouts (i.e., do something after N seconds), sockets (e.g., a new packet available for reading), and signals. eloop.c is an implementation of this interface using select() and sockets. This is suitable for most UNIX/POSIX systems. When porting to other operating systems, it may be necessary to replace that implementation with OS specific mechanisms.

Definition in file eloop.h.

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Typedef Documentation

typedef void(* eloop_event_handler)(void *eloop_data, void *user_ctx)

eloop generic event callback type Parameters: eloop_ctx  Registered callback context data (eloop_data) sock_ctx  Registered callback context data (user_data) Definition at line 61 of file eloop.h.

typedef void(* eloop_signal_handler)(int sig, void *eloop_ctx, void *signal_ctx)

eloop signal event callback type Parameters: sig  Signal number eloop_ctx  Registered callback context data (global user_data from eloop_init() call) signal_ctx  Registered callback context data (user_data from eloop_register_signal(), eloop_register_signal_terminate(), or eloop_register_signal_reconfig() call) Definition at line 81 of file eloop.h.

typedef void(* eloop_sock_handler)(int sock, void *eloop_ctx, void *sock_ctx)

eloop socket event callback type Parameters: sock  File descriptor number for the socket eloop_ctx  Registered callback context data (eloop_data) sock_ctx  Registered callback context data (user_data) Definition at line 53 of file eloop.h.

typedef void(* eloop_timeout_handler)(void *eloop_data, void *user_ctx)

eloop timeout event callback type Parameters: eloop_ctx  Registered callback context data (eloop_data) sock_ctx  Registered callback context data (user_data) Definition at line 69 of file eloop.h.

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Enumeration Type Documentation

enum eloop_event_type

eloop socket event type for eloop_register_sock() Parameters: EVENT_TYPE_READ  Socket has data available for reading EVENT_TYPE_WRITE  Socket has room for new data to be written EVENT_TYPE_EXCEPTION  An exception has been reported Definition at line 40 of file eloop.h.

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Function Documentation

int eloop_cancel_timeout (  eloop_timeout_handler  handler, void *  eloop_data, void *  user_data )

Cancel timeouts. Parameters: handler  Matching callback function eloop_data  Matching eloop_data or ELOOP_ALL_CTX to match all user_data  Matching user_data or ELOOP_ALL_CTX to match all Returns: Number of cancelled timeouts Cancel matching <handler,eloop_data,user_data> timeouts registered with eloop_register_timeout(). ELOOP_ALL_CTX can be used as a wildcard for cancelling all timeouts regardless of eloop_data/user_data. Definition at line 274 of file eloop.c.

void eloop_destroy (  void   )

Free any resources allocated for the event loop. After calling eloop_destroy(), other eloop_* functions must not be called before re-running eloop_init(). Definition at line 493 of file eloop.c.

void* eloop_get_user_data (  void   )

Get global user data. Returns: user_data pointer that was registered with eloop_init() Definition at line 529 of file eloop.c.

int eloop_init (  void *  user_data  )

Initialize global event loop data. Parameters: user_data  Pointer to global data passed as eloop_ctx to signal handlers Returns: 0 on success, -1 on failure This function must be called before any other eloop_* function. user_data can be used to configure a global (to the process) pointer that will be passed as eloop_ctx parameter to signal handlers. Definition at line 73 of file eloop.c.

int eloop_register_event (  void *  event, size_t  event_size, eloop_event_handler  handler, void *  eloop_data, void *  user_data )

Register handler for generic events. Parameters: event  Event to wait (eloop implementation specific) event_size  Size of event data handler  Callback function to be called when event is triggered eloop_data  Callback context data (eloop_data) user_data  Callback context data (user_data) Returns: 0 on success, -1 on failure Register an event handler for the given event. This function is used to register eloop implementation specific events which are mainly targetted for operating system specific code (driver interface and l2_packet) since the portable code will not be able to use such an OS-specific call. The handler function will be called whenever the event is triggered. The handler function is responsible for clearing the event after having processed it in order to avoid eloop from calling the handler again for the same event. In case of Windows implementation (eloop_win.c), event pointer is of HANDLE type, i.e., void*. The callers are likely to have 'HANDLE h' type variable, and they would call this function with eloop_register_event(h, sizeof(h), ...). Definition at line 191 of file eloop_win.c.

int eloop_register_read_sock (  int  sock, eloop_sock_handler  handler, void *  eloop_data, void *  user_data )

Register handler for read events. Parameters: sock  File descriptor number for the socket handler  Callback function to be called when data is available for reading eloop_data  Callback context data (eloop_ctx) user_data  Callback context data (sock_ctx) Returns: 0 on success, -1 on failure Register a read socket notifier for the given file descriptor. The handler function will be called whenever data is available for reading from the socket. The handler function is responsible for clearing the event after having processed it in order to avoid eloop from calling the handler again for the same event. Definition at line 177 of file eloop.c. Here is the call graph for this function:

int eloop_register_signal (  int  sig, eloop_signal_handler  handler, void *  user_data )

Register handler for signals. Parameters: sig  Signal number (e.g., SIGHUP) handler  Callback function to be called when the signal is received user_data  Callback context data (signal_ctx) Returns: 0 on success, -1 on failure Register a callback function that will be called when a signal is received. The callback function is actually called only after the system signal handler has returned. This means that the normal limits for sighandlers (i.e., only "safe functions" allowed) do not apply for the registered callback. Signals are 'global' events and there is no local eloop_data pointer like with other handlers. The global user_data pointer registered with eloop_init() will be used as eloop_ctx for signal handlers. Definition at line 369 of file eloop.c.

int eloop_register_signal_reconfig (  eloop_signal_handler  handler, void *  user_data )

Register handler for reconfig signals. Parameters: handler  Callback function to be called when the signal is received user_data  Callback context data (signal_ctx) Returns: 0 on success, -1 on failure Register a callback function that will be called when a reconfiguration / hangup signal is received. The callback function is actually called only after the system signal handler has returned. This means that the normal limits for sighandlers (i.e., only "safe functions" allowed) do not apply for the registered callback. Signals are 'global' events and there is no local eloop_data pointer like with other handlers. The global user_data pointer registered with eloop_init() will be used as eloop_ctx for signal handlers. This function is a more portable version of eloop_register_signal() since the knowledge of exact details of the signals is hidden in eloop implementation. In case of operating systems using signal(), this function registers a handler for SIGHUP. Definition at line 403 of file eloop.c. Here is the call graph for this function:

int eloop_register_signal_terminate (  eloop_signal_handler  handler, void *  user_data )

Register handler for terminate signals. Parameters: handler  Callback function to be called when the signal is received user_data  Callback context data (signal_ctx) Returns: 0 on success, -1 on failure Register a callback function that will be called when a process termination signal is received. The callback function is actually called only after the system signal handler has returned. This means that the normal limits for sighandlers (i.e., only "safe functions" allowed) do not apply for the registered callback. Signals are 'global' events and there is no local eloop_data pointer like with other handlers. The global user_data pointer registered with eloop_init() will be used as eloop_ctx for signal handlers. This function is a more portable version of eloop_register_signal() since the knowledge of exact details of the signals is hidden in eloop implementation. In case of operating systems using signal(), this function registers handlers for SIGINT and SIGTERM. Definition at line 393 of file eloop.c. Here is the call graph for this function:

int eloop_register_sock (  int  sock, eloop_event_type  type, eloop_sock_handler  handler, void *  eloop_data, void *  user_data )

Register handler for socket events. Parameters: sock  File descriptor number for the socket type  Type of event to wait for handler  Callback function to be called when the event is triggered eloop_data  Callback context data (eloop_ctx) user_data  Callback context data (sock_ctx) Returns: 0 on success, -1 on failure Register an event notifier for the given socket's file descriptor. The handler function will be called whenever the that event is triggered for the socket. The handler function is responsible for clearing the event after having processed it in order to avoid eloop from calling the handler again for the same event. Definition at line 206 of file eloop.c.

int eloop_register_timeout (  unsigned int  secs, unsigned int  usecs, eloop_timeout_handler  handler, void *  eloop_data, void *  user_data )

Register timeout. Parameters: secs  Number of seconds to the timeout usecs  Number of microseconds to the timeout handler  Callback function to be called when timeout occurs eloop_data  Callback context data (eloop_ctx) user_data  Callback context data (sock_ctx) Returns: 0 on success, -1 on failure Register a timeout that will cause the handler function to be called after given time. Definition at line 227 of file eloop.c. Here is the call graph for this function:

void eloop_run (  void   )

Start the event loop. Start the event loop and continue running as long as there are any registered event handlers. This function is run after event loop has been initialized with event_init() and one or more events have been registered. Definition at line 414 of file eloop.c. Here is the call graph for this function:

void eloop_terminate (  void   )

Terminate event loop. Terminate event loop even if there are registered events. This can be used to request the program to be terminated cleanly. Definition at line 487 of file eloop.c.

int eloop_terminated (  void   )

Check whether event loop has been terminated. Returns: 1 = event loop terminate, 0 = event loop still running This function can be used to check whether eloop_terminate() has been called to request termination of the event loop. This is normally used to abort operations that may still be queued to be run when eloop_terminate() was called. Definition at line 510 of file eloop.c.

void eloop_unregister_event (  void *  event, size_t  event_size )

Unregister handler for a generic event. Parameters: event  Event to cancel (eloop implementation specific) event_size  Size of event data Unregister a generic event notifier that was previously registered with eloop_register_event(). Definition at line 220 of file eloop_win.c.

void eloop_unregister_read_sock (  int  sock  )

Unregister handler for read events. Parameters: sock  File descriptor number for the socket Unregister a read socket notifier that was previously registered with eloop_register_read_sock(). Definition at line 185 of file eloop.c. Here is the call graph for this function:

void eloop_unregister_sock (  int  sock, eloop_event_type  type )

Unregister handler for socket events. Parameters: sock  File descriptor number for the socket type  Type of event for which sock was registered Unregister a socket event notifier that was previously registered with eloop_register_sock(). Definition at line 218 of file eloop.c.

void eloop_wait_for_read_sock (  int  sock  )

Wait for a single reader. Parameters: sock  File descriptor number for the socket Do a blocking wait for a single read socket. Definition at line 516 of file eloop.c.

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