RTEMS  5.0.0
Files | Data Structures | Typedefs | Variables
User Extension Handler

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.
 

Data Structures

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

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)
 
void _User_extensions_Add_set (User_extensions_Control *extension)
 
RTEMS_INLINE_ROUTINE void _User_extensions_Add_API_set (User_extensions_Control *extension)
 
RTEMS_INLINE_ROUTINE void _User_extensions_Add_set_with_table (User_extensions_Control *extension, const User_extensions_Table *extension_table)
 
void _User_extensions_Remove_set (User_extensions_Control *extension)
 
void _User_extensions_Thread_create_visitor (Thread_Control *executing, void *arg, const User_extensions_Table *callouts)
 
void _User_extensions_Thread_delete_visitor (Thread_Control *executing, void *arg, const User_extensions_Table *callouts)
 
void _User_extensions_Thread_start_visitor (Thread_Control *executing, void *arg, const User_extensions_Table *callouts)
 
void _User_extensions_Thread_restart_visitor (Thread_Control *executing, void *arg, const User_extensions_Table *callouts)
 
void _User_extensions_Thread_begin_visitor (Thread_Control *executing, void *arg, const User_extensions_Table *callouts)
 
void _User_extensions_Thread_exitted_visitor (Thread_Control *executing, void *arg, const User_extensions_Table *callouts)
 
void _User_extensions_Fatal_visitor (Thread_Control *executing, void *arg, const User_extensions_Table *callouts)
 
void _User_extensions_Thread_terminate_visitor (Thread_Control *executing, void *arg, const User_extensions_Table *callouts)
 
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...
 

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

◆ 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]executingThe executing thread.

◆ 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]executingThe executing thread.
[in]createdThe created thread.
Return values
trueSuccessful operation.
falseA 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.

◆ 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]executingThe executing thread.
[in]deletedThe deleted thread.

◆ 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]executingThe executing thread.

◆ 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]executingThe executing thread.
[in]restartedThe executing thread. Yes, the executing thread.

◆ 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]executingThe executing thread.
[in]startedThe started thread.

◆ 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]executingThe executing thread.
[in]heirThe heir thread.

◆ 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]terminatedThe terminated thread.

◆ User_extensions_Visitor

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

User extension visitor.

Parameters
[in,out]executingThe currently executing thread.
[in,out]argThe argument passed to _User_extensions_Iterate().
[in]calloutsThe current callouts.

Function Documentation

◆ _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]argThe argument passed to the visitor.
[in]visitorThe visitor for each extension.
[in]directionThe iteration direction for dynamic extensions.