Macros to abstract Thread Local Storage. More...

#include <freeradius-devel/util/debug.h>
#include <freeradius-devel/util/dlist.h>
#include <freeradius-devel/util/atexit.h>

Include dependency graph for atexit.c:

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Data Structures
struct	fr_atexit_entry_t
	Entry in exit handler list. More...

struct	fr_exit_handler_list_s
	Head of a list of exit handlers. More...

Macros
#define	ATEXIT_DEBUG(...)

#define	CHECK_GLOBAL_SETUP()

Typedefs
typedef struct fr_exit_handler_list_s	fr_atexit_list_t

Functions
static int	_atexit_entry_free (fr_atexit_entry_t *e)
	Call the exit handler. More...

int	_atexit_global (char const file, int line, fr_atexit_t func, void const uctx)
	Add a free function to be called when the process exits. More...

static int	_destructor_list_free (fr_atexit_list_t *list)
	Talloc destructor for freeing list elements in order. More...

static void	_global_free (void)
	Free any thread-local exit handler lists that pthread_key failed to fre. More...

static fr_atexit_entry_t *	atexit_entry_alloc (char const file, int line, fr_atexit_list_t list, fr_atexit_t func, void const *uctx)
	Allocate a new exit handler entry. More...

unsigned int	fr_atexit_global_disarm (bool uctx_scope, fr_atexit_t func, void const *uctx)
	Remove a specific global destructor (without executing it) More...

void	fr_atexit_global_disarm_all (void)
	Remove all global destructors (without executing them) More...

int	fr_atexit_global_setup (void)
	Setup the atexit handler, should be called at the start of a program's execution. More...

int	fr_atexit_global_trigger_all (void)
	Cause all global free triggers to fire. More...

bool	fr_atexit_is_exiting (void)
	Return whether we're currently in the teardown phase. More...

int	fr_atexit_trigger (bool uctx_scope, fr_atexit_t func, void const *uctx)
	Iterates through all thread local destructor lists, causing destructor to be triggered. More...

Variables
static fr_atexit_list_t *	fr_atexit_global = NULL

static bool	is_exiting

static _Thread_local bool	thread_is_exiting

Detailed Description

Macros to abstract Thread Local Storage.

Simplifies calling thread local destructors (called when the thread exits).

Copyright: 2020-2021 Arran Cudbard-Bell (a.cud.nosp@m.bard.nosp@m.b@fre.nosp@m.erad.nosp@m.ius.o.nosp@m.rg); 2020 The FreeRADIUS server project

Definition in file atexit.c.

Data Structure Documentation

◆ fr_atexit_entry_t

struct fr_atexit_entry_t

Entry in exit handler list.

Definition at line 48 of file atexit.c.

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Data Fields
fr_dlist_t	entry	Entry in the handler dlist.
char const *	file	File where this exit handler was added.
fr_atexit_t	func	Function to call.
int	line	Line where this exit handler was added.
fr_atexit_list_t *	list	List this entry is in.
void *	uctx	uctx to pass.

◆ fr_exit_handler_list_s

struct fr_exit_handler_list_s

Head of a list of exit handlers.

Definition at line 62 of file atexit.c.

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Data Fields
fr_atexit_entry_t *	e	Inserted into the global exit handler list to ensure this memory is cleaned up.
fr_dlist_head_t	head	Head of the list of destructors.
pthread_key_t	key	Key used to trigger thread local destructors.

Macro Definition Documentation

◆ ATEXIT_DEBUG

#define ATEXIT_DEBUG ( ... )

Definition at line 40 of file atexit.c.

◆ CHECK_GLOBAL_SETUP

#define CHECK_GLOBAL_SETUP ( )

Value:

do { \
        int _ret = 0; \
        fr_cond_assert_msg(!is_exiting, "New atexit handlers should not be allocated whilst exiting"); \
        if (!fr_atexit_global) _ret = fr_atexit_global_setup(); \
        if (_ret < 0) return _ret; \
} while(0)

Definition at line 198 of file atexit.c.

Typedef Documentation

◆ fr_atexit_list_t

typedef struct fr_exit_handler_list_s fr_atexit_list_t

Definition at line 1 of file atexit.c.

Function Documentation

◆ _atexit_entry_free()

static int _atexit_entry_free ( fr_atexit_entry_t * e )

static

Call the exit handler.

Definition at line 83 of file atexit.c.

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◆ _atexit_global()

int _atexit_global	(	char const *	file,
		int	line,
		fr_atexit_t	func,
		void const *	uctx
	)

Add a free function to be called when the process exits.

Definition at line 210 of file atexit.c.

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◆ _destructor_list_free()

static int _destructor_list_free ( fr_atexit_list_t * list )

static

Talloc destructor for freeing list elements in order.

Definition at line 130 of file atexit.c.

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◆ _global_free()

static void _global_free ( void )

static

Free any thread-local exit handler lists that pthread_key failed to fre.

Definition at line 141 of file atexit.c.

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◆ atexit_entry_alloc()

static fr_atexit_entry_t* atexit_entry_alloc	(	char const *	file,
		int	line,
		fr_atexit_list_t *	list,
		fr_atexit_t	func,
		void const *	uctx
	)

static

Allocate a new exit handler entry.

Definition at line 102 of file atexit.c.

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◆ fr_atexit_global_disarm()

unsigned int fr_atexit_global_disarm	(	bool	uctx_scope,
		fr_atexit_t	func,
		void const *	uctx
	)

Remove a specific global destructor (without executing it)

Note: This function's primary purpose is to help diagnose issues with destructors from within a debugger.

Parameters

[in]	uctx_scope	Only process entries where the func and scope both match.
[in]	func	Entries matching this function will be disarmed.
[in]	uctx	associated with the entry.

Returns: How many global destructors were disarmed.

Definition at line 229 of file atexit.c.

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◆ fr_atexit_global_disarm_all()

void fr_atexit_global_disarm_all ( void )

Remove all global destructors (without executing them)

Note: This function's primary purpose is to help diagnose issues with destructors from within a debugger.

Definition at line 259 of file atexit.c.

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◆ fr_atexit_global_setup()

int fr_atexit_global_setup ( void )

Setup the atexit handler, should be called at the start of a program's execution.

Definition at line 160 of file atexit.c.

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◆ fr_atexit_global_trigger_all()

int fr_atexit_global_trigger_all ( void )

Cause all global free triggers to fire.

This is necessary when libraries (perl) register their own atexit handlers using the normal POSIX mechanism, and we need to ensure all our atexit handlers fire before so any global deinit is done explicitly by us.

Returns

>= 0 The number of atexit handlers triggered on success.
<0 the return code from any atexit handlers that returned an error.

Definition at line 286 of file atexit.c.

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◆ fr_atexit_is_exiting()

bool fr_atexit_is_exiting ( void )

Return whether we're currently in the teardown phase.

When this function returns true no more thread local or global destructors can be added.

Definition at line 412 of file atexit.c.

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◆ fr_atexit_trigger()

int fr_atexit_trigger	(	bool	uctx_scope,
		fr_atexit_t	func,
		void const *	uctx
	)

Iterates through all thread local destructor lists, causing destructor to be triggered.

This should only be called by the main process not by threads.

The main purpose of the function is to force cleanups at a specific time for problematic destructors.

Parameters

[in]	uctx_scope	Only process entries where the func and scope both match.
[in]	func	Entries matching this function will be triggered.
[in]	uctx	associated with the entry.

Returns

>= 0 The number of atexit handlers triggered on success.
<0 the return code from any atexit handlers that returned an error.

Definition at line 331 of file atexit.c.

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Variable Documentation

◆ fr_atexit_global

fr_atexit_list_t* fr_atexit_global = NULL

static

Definition at line 76 of file atexit.c.

◆ is_exiting

bool is_exiting

static

Definition at line 77 of file atexit.c.

◆ thread_is_exiting

_Thread_local bool thread_is_exiting

static

Definition at line 78 of file atexit.c.

Data Structures

Macros

Typedefs

Functions

Variables

Detailed Description

Data Structure Documentation

◆ fr_atexit_entry_t

◆ fr_exit_handler_list_s

Macro Definition Documentation

◆ ATEXIT_DEBUG

◆ CHECK_GLOBAL_SETUP

Typedef Documentation

◆ fr_atexit_list_t

Function Documentation

◆ _atexit_entry_free()

◆ _atexit_global()

◆ _destructor_list_free()

◆ _global_free()

◆ atexit_entry_alloc()

◆ fr_atexit_global_disarm()

◆ fr_atexit_global_disarm_all()

◆ fr_atexit_global_setup()

◆ fr_atexit_global_trigger_all()

◆ fr_atexit_is_exiting()

◆ fr_atexit_trigger()

Variable Documentation

◆ fr_atexit_global

◆ is_exiting

◆ thread_is_exiting