The User Extension Handler provides invocation of application dependent routines at critical points in the life of each thread and the system as a whole. More...

Files
file	userext.h
	User Extension Handler API.

file	userextdata.h
	User Extension Handler Data Structures.

file	userextimpl.h
	User Extension Handler API.

file	userext.c
	User Extension Handler implementation.

file	userextaddset.c
	User Extension Handler implementation.

file	userextiterate.c
	User Extension Iteration Helpers.

file	userextremoveset.c
	User Extension Handler implementation.

Classes
struct	User_extensions_Table
	User extension table. More...

struct	User_extensions_Switch_control
	Manages the switch callouts. More...

struct	User_extensions_Control
	Manages each user extension set. More...

struct	User_extensions_Iterator
	Chain iterator for dynamic user extensions. More...

struct	User_extensions_List

struct	User_extensions_Thread_create_context

struct	User_extensions_Fatal_context

Typedefs
typedef bool(*	User_extensions_thread_create_extension) (struct _Thread_Control executing, struct _Thread_Control created)
	Task create extension. More...

typedef void(*	User_extensions_thread_delete_extension) (struct _Thread_Control executing, struct _Thread_Control deleted)
	Task delete extension. More...

typedef void(*	User_extensions_thread_start_extension) (struct _Thread_Control executing, struct _Thread_Control started)
	Task start extension. More...

typedef void(*	User_extensions_thread_restart_extension) (struct _Thread_Control executing, struct _Thread_Control restarted)
	Task restart extension. More...

typedef void(*	User_extensions_thread_switch_extension) (struct _Thread_Control executing, struct _Thread_Control heir)
	Task switch extension. More...

typedef void(*	User_extensions_thread_begin_extension) (struct _Thread_Control *executing)
	Task begin extension. More...

typedef void(*	User_extensions_thread_exitted_extension) (struct _Thread_Control *executing)
	Task exitted extension. More...

typedef void(*	User_extensions_fatal_extension) (Internal_errors_Source source, bool always_set_to_false, Internal_errors_t code)
	Fatal error extension. More...

typedef void(*	User_extensions_thread_terminate_extension) (struct _Thread_Control *terminated)
	Task termination extension. More...

typedef struct User_extensions_Iterator	User_extensions_Iterator
	Chain iterator for dynamic user extensions. More...

Variables
const size_t	_User_extensions_Initial_count
	The count of initial user extensions. More...

const User_extensions_Table	_User_extensions_Initial_extensions []
	The table of initial user extensions. More...

User_extensions_Switch_control	_User_extensions_Initial_switch_controls []
	A spare switch control for each initial user extension. More...

User_extensions_List	_User_extensions_List
	List of active extensions.

Chain_Control	_User_extensions_Switches_list
	List of active task switch extensions.

Extension Maintainance
typedef void(*	User_extensions_Visitor) (Thread_Control executing, void arg, const User_extensions_Table *callouts)
	User extension visitor. More...

void	_User_extensions_Handler_initialization (void)
	Initializes the user extensions handler.

void	_User_extensions_Add_set (User_extensions_Control *extension)
	Adds a user extension. More...

static __inline__ void	_User_extensions_Add_API_set (User_extensions_Control *extension)
	Adds a user extension. More...

static __inline__ void	_User_extensions_Add_set_with_table (User_extensions_Control extension, const User_extensions_Table extension_table)
	Adds a user extension with the given extension table as callouts. More...

void	_User_extensions_Remove_set (User_extensions_Control *extension)
	Removes a user extension. More...

void	_User_extensions_Thread_create_visitor (Thread_Control executing, void arg, const User_extensions_Table *callouts)
	Creates a visitor. More...

void	_User_extensions_Thread_delete_visitor (Thread_Control executing, void arg, const User_extensions_Table *callouts)
	Deletes a visitor. More...

void	_User_extensions_Thread_start_visitor (Thread_Control executing, void arg, const User_extensions_Table *callouts)
	Starts a visitor. More...

void	_User_extensions_Thread_restart_visitor (Thread_Control executing, void arg, const User_extensions_Table *callouts)
	Restarts a visitor. More...

void	_User_extensions_Thread_begin_visitor (Thread_Control executing, void arg, const User_extensions_Table *callouts)
	Calls the begin function of the thread callout for the visitor. More...

void	_User_extensions_Thread_exitted_visitor (Thread_Control executing, void arg, const User_extensions_Table *callouts)
	Calls the exitted function of the thread callout for the visitor. More...

void	_User_extensions_Fatal_visitor (Thread_Control executing, void arg, const User_extensions_Table *callouts)
	Calls the fatal function of the thread callout for the visitor. More...

void	_User_extensions_Thread_terminate_visitor (Thread_Control executing, void arg, const User_extensions_Table *callouts)
	Terminates a visitor. More...

void	_User_extensions_Iterate (void *arg, User_extensions_Visitor visitor, Chain_Iterator_direction direction)
	Iterates through all user extensions and calls the visitor for each. More...

Extension Callout Dispatcher
static bool	_User_extensions_Thread_create (Thread_Control *created)
	Creates a thread. More...

static void	_User_extensions_Thread_delete (Thread_Control *deleted)
	Deletes a thread. More...

static void	_User_extensions_Thread_start (Thread_Control *started)
	Starts a thread. More...

static void	_User_extensions_Thread_restart (Thread_Control *restarted)
	Restarts a thread. More...

static void	_User_extensions_Thread_begin (Thread_Control *executing)
	Begins a thread. More...

static void	_User_extensions_Thread_switch (Thread_Control executing, Thread_Control heir)
	Switches the thread from the executing to the heir. More...

static void	_User_extensions_Thread_exitted (Thread_Control *executing)
	A user extension thread exitted. More...

static void	_User_extensions_Fatal (Internal_errors_Source source, Internal_errors_t error)
	Forwards all visitors that there was a fatal failure. More...

static void	_User_extensions_Thread_terminate (Thread_Control *executing)
	Terminates the executing thread. More...

static void	_User_extensions_Acquire (ISR_lock_Context *lock_context)
	Disables interrupts and acquires the lock context. More...

static void	_User_extensions_Release (ISR_lock_Context *lock_context)
	Releases the lock context and enables interrupts. More...

static void	_User_extensions_Destroy_iterators (Thread_Control *the_thread)
	Destroys all user extension iterators of a thread. More...

Detailed Description

The User Extension Handler provides invocation of application dependent routines at critical points in the life of each thread and the system as a whole.

Typedef Documentation

◆ User_extensions_fatal_extension

typedef void( * User_extensions_fatal_extension) (Internal_errors_Source source, bool always_set_to_false, Internal_errors_t code)

Fatal error extension.

It corresponds to _Terminate() (used by the rtems_fatal() directive).

This extension should not call any RTEMS directives.

Parameters

[in]	source	The fatal source indicating the subsystem the fatal condition originated in.
[in]	always_set_to_false	This parameter is always set to false and provided only for backward compatibility reasons.
[in]	code	The fatal error code. This value must be interpreted with respect to the source.

Definition at line 201 of file userext.h.

◆ User_extensions_Iterator

typedef struct User_extensions_Iterator User_extensions_Iterator

Chain iterator for dynamic user extensions.

Since user extensions may delete or restart the executing thread, we must clean up registered iterators.

See also: _User_extensions_Iterate(), _User_extensions_Destroy_iterators() and Thread_Control::last_user_extensions_iterator.

◆ User_extensions_thread_begin_extension

typedef void( * User_extensions_thread_begin_extension) (struct _Thread_Control *executing)

Task begin extension.

It corresponds to _Thread_Handler().

Thread dispatching is disabled. The executing thread is not the holder of the allocator mutex.

Parameters

[in] executing The executing thread.

Definition at line 169 of file userext.h.

◆ User_extensions_thread_create_extension

typedef bool( * User_extensions_thread_create_extension) (struct _Thread_Control *executing, struct _Thread_Control *created)

Task create extension.

It corresponds to _Thread_Initialize() (used by the rtems_task_create() directive and pthread_create()).

It is invoked after the new thread has been completely initialized, but before it is placed on a ready chain.

Thread dispatching may be disabled. This depends on the context of the _Thread_Initialize() call. Thread dispatch is disabled during the creation of the idle thread and the initialization threads. It can be considered as an invalid API usage, if the application calls _Thread_Initialize() with disabled thread dispatching. Disabled thread dispatching is different from disabled preemption.

It can be assumed that the executing thread locked the allocator mutex. The only exception is the creation of the idle thread. In this case the allocator mutex is not locked. Since the allocator mutex allows nesting the normal memory allocation routines can be used.

Parameters

[in]	executing	The executing thread.
[in]	created	The created thread.

Return values

true	Successful operation.
false	A thread create user extension will frequently attempt to allocate resources. If this allocation fails, then the extension should return false and the entire thread create operation will fail.

Definition at line 69 of file userext.h.

◆ User_extensions_thread_delete_extension

typedef void( * User_extensions_thread_delete_extension) (struct _Thread_Control *executing, struct _Thread_Control *deleted)

Task delete extension.

It corresponds to _Thread_Close() (used by the rtems_task_delete() directive, pthread_exit() and pthread_cancel()).

It is invoked before all resources of the thread are deleted. The executing and deleted arguments are never equal.

Thread dispatching is enabled. The executing thread locked the allocator mutex.

Parameters

[in]	executing	The executing thread.
[in]	deleted	The deleted thread.

Definition at line 89 of file userext.h.

◆ User_extensions_thread_exitted_extension

typedef void( * User_extensions_thread_exitted_extension) (struct _Thread_Control *executing)

Task exitted extension.

It corresponds to _Thread_Handler() after a return of the entry function.

Thread dispatching is disabled. The state of the allocator mutex is arbitrary.

Parameters

[in] executing The executing thread.

Definition at line 183 of file userext.h.

◆ User_extensions_thread_restart_extension

typedef void( * User_extensions_thread_restart_extension) (struct _Thread_Control *executing, struct _Thread_Control *restarted)

Task restart extension.

It corresponds to _Thread_Restart() (used by the rtems_task_restart() directive).

It is invoked in the context of the restarted thread right before the execution context is reloaded. The executing and restarted arguments are always equal. The thread stack reflects the previous execution context.

Thread dispatching is enabled. The thread is not the holder of the allocator mutex. The thread life is protected. Thread restart and delete requests issued by restart extensions lead to recursion.

Parameters

[in]	executing	The executing thread.
[in]	restarted	The executing thread. Yes, the executing thread.

Definition at line 131 of file userext.h.

◆ User_extensions_thread_start_extension

typedef void( * User_extensions_thread_start_extension) (struct _Thread_Control *executing, struct _Thread_Control *started)

Task start extension.

It corresponds to _Thread_Start() (used by the rtems_task_start() directive).

It is invoked after the environment of the thread has been loaded and the thread has been made ready.

Thread dispatching is disabled. The executing thread is not the holder of the allocator mutex.

Parameters

[in]	executing	The executing thread.
[in]	started	The started thread.

Definition at line 109 of file userext.h.

◆ User_extensions_thread_switch_extension

typedef void( * User_extensions_thread_switch_extension) (struct _Thread_Control *executing, struct _Thread_Control *heir)

Task switch extension.

It corresponds to _Thread_Dispatch().

It is invoked before the context switch from the executing to the heir thread.

Thread dispatching is disabled. The state of the allocator mutex is arbitrary. Interrupts are disabled and the per-CPU lock is acquired on SMP configurations.

The context switches initiated through _Thread_Start_multitasking() are not covered by this extension.

Parameters

[in]	executing	The executing thread.
[in]	heir	The heir thread.

Definition at line 154 of file userext.h.

◆ User_extensions_thread_terminate_extension

typedef void( * User_extensions_thread_terminate_extension) (struct _Thread_Control *terminated)

Task termination extension.

This extension is invoked by _Thread_Life_action_handler() in case a termination request is recognized.

It is invoked in the context of the terminated thread right before the thread dispatch to the heir thread. The POSIX cleanup and key destructors execute in this context.

Thread dispatching is enabled. The thread is not the holder of the allocator mutex. The thread life is protected. Thread restart and delete requests issued by terminate extensions lead to recursion.

Parameters

[in] terminated The terminated thread.

Definition at line 223 of file userext.h.

◆ User_extensions_Visitor

typedef void(* User_extensions_Visitor) (Thread_Control *executing, void *arg, const User_extensions_Table *callouts)

User extension visitor.

Parameters

[in,out]	executing	The currently executing thread.
[in,out]	arg	The argument passed to _User_extensions_Iterate().
[in]	callouts	The current callouts.

Definition at line 143 of file userextimpl.h.

Function Documentation

◆ _User_extensions_Acquire()

static void _User_extensions_Acquire ( ISR_lock_Context * lock_context )

inlinestatic

Disables interrupts and acquires the lock context.

Parameters

lock_context The lock context to acquire.

Definition at line 473 of file userextimpl.h.

◆ _User_extensions_Add_API_set()

static __inline__ void _User_extensions_Add_API_set ( User_extensions_Control * extension )

static

Adds a user extension.

Parameters

extension The user extension to add.

Definition at line 104 of file userextimpl.h.

◆ _User_extensions_Add_set()

void _User_extensions_Add_set ( User_extensions_Control * extension )

Adds a user extension.

Parameters

extension The user extension to add.

Definition at line 45 of file userextaddset.c.

◆ _User_extensions_Add_set_with_table()

static __inline__ void _User_extensions_Add_set_with_table	(	User_extensions_Control *	extension,
		const User_extensions_Table *	extension_table
	)

static

Adds a user extension with the given extension table as callouts.

Parameters

[in,out]	extension	The user extension to add.
	extension_table	Is set as callouts for extension.

Definition at line 117 of file userextimpl.h.

◆ _User_extensions_Destroy_iterators()

static void _User_extensions_Destroy_iterators ( Thread_Control * the_thread )

inlinestatic

Destroys all user extension iterators of a thread.

Parameters

[in,out] the_thread The thread to destroy all user extension iterators of.

Definition at line 500 of file userextimpl.h.

◆ _User_extensions_Fatal()

static void _User_extensions_Fatal	(	Internal_errors_Source	source,
		Internal_errors_t	error
	)

inlinestatic

Forwards all visitors that there was a fatal failure.

Parameters

source	The error source.
error	The error.

Definition at line 438 of file userextimpl.h.

◆ _User_extensions_Fatal_visitor()

void _User_extensions_Fatal_visitor	(	Thread_Control *	executing,
		void *	arg,
		const User_extensions_Table *	callouts
	)

Calls the fatal function of the thread callout for the visitor.

Parameters

executing	The currently executing thread.
arg	Is used as the user extension fatal context.
callouts	The user extension table for the operation.

Definition at line 120 of file userextiterate.c.

◆ _User_extensions_Iterate()

void _User_extensions_Iterate	(	void *	arg,
		User_extensions_Visitor	visitor,
		Chain_Iterator_direction	direction
	)

Iterates through all user extensions and calls the visitor for each.

Parameters

[in,out]	arg	The argument passed to the visitor.
	visitor	The visitor for each extension.
	direction	The iteration direction for dynamic extensions.

Definition at line 149 of file userextiterate.c.

◆ _User_extensions_Release()

static void _User_extensions_Release ( ISR_lock_Context * lock_context )

inlinestatic

Releases the lock context and enables interrupts.

Parameters

lock_context The lock context to release.

Definition at line 486 of file userextimpl.h.

◆ _User_extensions_Remove_set()

void _User_extensions_Remove_set ( User_extensions_Control * extension )

Removes a user extension.

Parameters

extension The user extension to remove.

Definition at line 25 of file userextremoveset.c.

◆ _User_extensions_Thread_begin()

static void _User_extensions_Thread_begin ( Thread_Control * executing )

inlinestatic

Begins a thread.

Parameters

created The thread to begin.

Definition at line 351 of file userextimpl.h.

◆ _User_extensions_Thread_begin_visitor()

void _User_extensions_Thread_begin_visitor	(	Thread_Control *	executing,
		void *	arg,
		const User_extensions_Table *	callouts
	)

Calls the begin function of the thread callout for the visitor.

Parameters

executing	The currently executing thread.
arg	This parameter is unused.
callouts	The user extension table for the operation.

Definition at line 94 of file userextiterate.c.

◆ _User_extensions_Thread_create()

static bool _User_extensions_Thread_create ( Thread_Control * created )

inlinestatic

Creates a thread.

Parameters

[out] created The thread to create.

Return values

true	The operation succeeded.
false	The operation failed.

Definition at line 291 of file userextimpl.h.

◆ _User_extensions_Thread_create_visitor()

void _User_extensions_Thread_create_visitor	(	Thread_Control *	executing,
		void *	arg,
		const User_extensions_Table *	callouts
	)

Creates a visitor.

Parameters

	executing	The currently executing thread.
[in,out]	arg	Is used as the thread create context for the operation.
	callouts	The user extension table for the operation.

Definition at line 40 of file userextiterate.c.

◆ _User_extensions_Thread_delete()

static void _User_extensions_Thread_delete ( Thread_Control * deleted )

inlinestatic

Deletes a thread.

Parameters

[out] created The thread to delete.

Definition at line 309 of file userextimpl.h.

◆ _User_extensions_Thread_delete_visitor()

void _User_extensions_Thread_delete_visitor	(	Thread_Control *	executing,
		void *	arg,
		const User_extensions_Table *	callouts
	)

Deletes a visitor.

Parameters

	executing	The currently executing thread.
[in,out]	arg	Parameter for the callout.
	callouts	The user extension table for the operation.

Definition at line 55 of file userextiterate.c.

◆ _User_extensions_Thread_exitted()

static void _User_extensions_Thread_exitted ( Thread_Control * executing )

inlinestatic

A user extension thread exitted.

Parameters

created The thread.

Definition at line 423 of file userextimpl.h.

◆ _User_extensions_Thread_exitted_visitor()

void _User_extensions_Thread_exitted_visitor	(	Thread_Control *	executing,
		void *	arg,
		const User_extensions_Table *	callouts
	)

Calls the exitted function of the thread callout for the visitor.

Parameters

executing	The currently executing thread.
arg	This parameter is unused.
callouts	The user extension table for the operation.

Definition at line 107 of file userextiterate.c.

◆ _User_extensions_Thread_restart()

static void _User_extensions_Thread_restart ( Thread_Control * restarted )

inlinestatic

Restarts a thread.

Parameters

created The thread to restart.

Definition at line 337 of file userextimpl.h.

◆ _User_extensions_Thread_restart_visitor()

void _User_extensions_Thread_restart_visitor	(	Thread_Control *	executing,
		void *	arg,
		const User_extensions_Table *	callouts
	)

Restarts a visitor.

Parameters

executing	The currently executing thread.
arg	Parameter for the callout.
callouts	The user extension table for the operation.

Definition at line 81 of file userextiterate.c.

◆ _User_extensions_Thread_start()

static void _User_extensions_Thread_start ( Thread_Control * started )

inlinestatic

Starts a thread.

Parameters

created The thread to start.

Definition at line 323 of file userextimpl.h.

◆ _User_extensions_Thread_start_visitor()

void _User_extensions_Thread_start_visitor	(	Thread_Control *	executing,
		void *	arg,
		const User_extensions_Table *	callouts
	)

Starts a visitor.

Parameters

executing	The currently executing thread.
arg	Parameter for the callout.
callouts	The user extension table for the operation.

Definition at line 68 of file userextiterate.c.

◆ _User_extensions_Thread_switch()

static void _User_extensions_Thread_switch	(	Thread_Control *	executing,
		Thread_Control *	heir
	)

inlinestatic

Switches the thread from the executing to the heir.

Parameters

executing	The currently executing thread.
heir	The thread that will switch with executing.

Definition at line 366 of file userextimpl.h.

◆ _User_extensions_Thread_terminate()

static void _User_extensions_Thread_terminate ( Thread_Control * executing )

inlinestatic

Terminates the executing thread.

Parameters

executing The currently executing thread.

Definition at line 457 of file userextimpl.h.

◆ _User_extensions_Thread_terminate_visitor()

void _User_extensions_Thread_terminate_visitor	(	Thread_Control *	executing,
		void *	arg,
		const User_extensions_Table *	callouts
	)

Terminates a visitor.

Parameters

executing	The currently executing thread.
arg	This parameter is unused.
callouts	The user extension table for the operation.

Definition at line 135 of file userextiterate.c.

Variable Documentation

◆ _User_extensions_Initial_count

const size_t _User_extensions_Initial_count

The count of initial user extensions.

Application provided via <rtems/confdefs.h>.

◆ _User_extensions_Initial_extensions

const User_extensions_Table _User_extensions_Initial_extensions[]

The table of initial user extensions.

Application provided via <rtems/confdefs.h>.

◆ _User_extensions_Initial_switch_controls

User_extensions_Switch_control _User_extensions_Initial_switch_controls[]

A spare switch control for each initial user extension.

Application provided via <rtems/confdefs.h>.

Files

Classes

Typedefs

Variables

Extension Maintainance

Extension Callout Dispatcher

Detailed Description

Typedef Documentation

◆ User_extensions_fatal_extension

◆ User_extensions_Iterator

◆ User_extensions_thread_begin_extension

◆ User_extensions_thread_create_extension

◆ User_extensions_thread_delete_extension

◆ User_extensions_thread_exitted_extension

◆ User_extensions_thread_restart_extension

◆ User_extensions_thread_start_extension

◆ User_extensions_thread_switch_extension

◆ User_extensions_thread_terminate_extension

◆ User_extensions_Visitor

Function Documentation

◆ _User_extensions_Acquire()

◆ _User_extensions_Add_API_set()

◆ _User_extensions_Add_set()

◆ _User_extensions_Add_set_with_table()

◆ _User_extensions_Destroy_iterators()

◆ _User_extensions_Fatal()

◆ _User_extensions_Fatal_visitor()

◆ _User_extensions_Iterate()

◆ _User_extensions_Release()

◆ _User_extensions_Remove_set()

◆ _User_extensions_Thread_begin()

◆ _User_extensions_Thread_begin_visitor()

◆ _User_extensions_Thread_create()

◆ _User_extensions_Thread_create_visitor()

◆ _User_extensions_Thread_delete()

◆ _User_extensions_Thread_delete_visitor()

◆ _User_extensions_Thread_exitted()

◆ _User_extensions_Thread_exitted_visitor()

◆ _User_extensions_Thread_restart()

◆ _User_extensions_Thread_restart_visitor()

◆ _User_extensions_Thread_start()

◆ _User_extensions_Thread_start_visitor()

◆ _User_extensions_Thread_switch()

◆ _User_extensions_Thread_terminate()

◆ _User_extensions_Thread_terminate_visitor()

Variable Documentation

◆ _User_extensions_Initial_count

◆ _User_extensions_Initial_extensions

◆ _User_extensions_Initial_switch_controls