interpret.c File Reference

Execute compiled unlang structures using an iterative interpret. More...

#include <freeradius-devel/unlang/interpret.h>
#include <freeradius-devel/util/timer.h>
#include <freeradius-devel/server/base.h>
#include <freeradius-devel/server/modpriv.h>
#include <freeradius-devel/unlang/xlat_func.h>
#include "interpret_priv.h"
#include "module_priv.h"

Include dependency graph for interpret.c:

Go to the source code of this file.

Data Structures
struct	unlang_variable_ref_t

Macros
#define	DUMP_STACK   if (DEBUG_ENABLED5) stack_dump(request)

Functions
static int	_local_variables_free (unlang_variable_ref_t *ref)
static void	frame_dump (request_t *request, unlang_stack_frame_t *frame)
static unlang_frame_action_t	frame_eval (request_t *request, unlang_stack_frame_t *frame, rlm_rcode_t *result, int *priority)
	Evaluates all the unlang nodes in a section.
static void	instruction_dump (request_t *request, unlang_t const *instruction)
static void	instruction_retry_handler (UNUSED fr_timer_list_t *tl, UNUSED fr_time_t now, void *ctx)
static void	instruction_timeout_handler (UNUSED fr_timer_list_t *tl, UNUSED fr_time_t now, void *ctx)
static unlang_frame_action_t	result_calculate (request_t *request, unlang_stack_frame_t *frame, rlm_rcode_t *result, int *priority)
	Update the current result after each instruction, and after popping each stack frame.
static void	stack_dump (request_t *request)
static void	unlang_cancel_event (UNUSED fr_timer_list_t *tl, UNUSED fr_time_t now, void *uctx)
	Signal the request to stop executing.
static xlat_action_t	unlang_cancel_xlat (TALLOC_CTX *ctx, fr_dcursor_t *out, UNUSED xlat_ctx_t const *xctx, request_t *request, fr_value_box_list_t *args)
	Allows a request to dynamically alter its own lifetime.
void	unlang_interpet_frame_discard (request_t *request)
	Discard the bottom most frame on the request's stack.
rlm_rcode_t	unlang_interpret (request_t *request, bool running)
	Run the interpreter for a current request.
fr_event_list_t *	unlang_interpret_event_list (request_t *request)
	Get the event list for the current interpreter.
TALLOC_CTX *	unlang_interpret_frame_talloc_ctx (request_t *request)
	Get a talloc_ctx which is valid only for this frame.
unlang_interpret_t *	unlang_interpret_get (request_t *request)
	Get the interpreter set for a request.
unlang_interpret_t *	unlang_interpret_get_thread_default (void)
	Get the default interpreter for this thread.
unlang_interpret_t *	unlang_interpret_init (TALLOC_CTX *ctx, fr_event_list_t *el, unlang_request_func_t *funcs, void *uctx)
	Initialize a unlang compiler / interpret.
int	unlang_interpret_init_global (TALLOC_CTX *ctx)
bool	unlang_interpret_is_resumable (request_t *request)
	Check if a request as resumable.
void	unlang_interpret_mark_runnable (request_t *request)
	Mark a request as resumable.
int	unlang_interpret_push (request_t *request, unlang_t const *instruction, rlm_rcode_t default_rcode, bool do_next_sibling, bool top_frame)
	Push a new frame onto the stack.
unlang_action_t	unlang_interpret_push_children (UNUSED rlm_rcode_t *p_result, request_t *request, rlm_rcode_t default_rcode, bool do_next_sibling)
	Push the children of the current frame onto a new frame onto the stack.
int	unlang_interpret_push_instruction (request_t *request, void *instruction, rlm_rcode_t default_rcode, bool top_frame)
	Push an instruction onto the request stack for later interpretation.
int	unlang_interpret_push_section (request_t *request, CONF_SECTION *cs, rlm_rcode_t default_rcode, bool top_frame)
	Push a configuration section onto the request stack for later interpretation.
static void	unlang_interpret_request_detach (request_t *request)
	Tell the interpreter to detach the request.
void	unlang_interpret_request_done (request_t *request)
	Indicate to the caller of the interpreter that this request is complete.
void	unlang_interpret_request_prioritise (request_t *request, uint32_t priority)
void	unlang_interpret_set (request_t *request, unlang_interpret_t *intp)
	Set a specific interpreter for a request.
void	unlang_interpret_set_thread_default (unlang_interpret_t *intp)
	Set the default interpreter for this thread.
int	unlang_interpret_set_timeout (request_t *request, fr_time_delta_t timeout)
	Set a timeout for a request.
void	unlang_interpret_signal (request_t *request, fr_signal_t action)
	Send a signal (usually stop) to a request.
void *	unlang_interpret_stack_alloc (TALLOC_CTX *ctx)
	Allocate a new unlang stack.
int	unlang_interpret_stack_depth (request_t *request)
	Return the depth of the request's stack.
rlm_rcode_t	unlang_interpret_stack_result (request_t *request)
	Get the current rcode for the frame.
void	unlang_interpret_stack_result_set (request_t *request, rlm_rcode_t rcode)
	Overwrite the current stack rcode.
static xlat_action_t	unlang_interpret_xlat (TALLOC_CTX *ctx, fr_dcursor_t *out, UNUSED xlat_ctx_t const *xctx, request_t *request, fr_value_box_list_t *in)
	Get information about the interpreter state.
bool	unlang_request_is_cancelled (request_t const *request)
	Return whether a request has been cancelled.
bool	unlang_request_is_done (request_t const *request)
	Return whether a request has been marked done.
bool	unlang_request_is_scheduled (request_t const *request)
	Return whether a request is currently scheduled.
void	unlang_stack_signal (request_t *request, fr_signal_t action, int limit)
	Delivers a frame to one or more frames in the stack.

Variables
static unlang_group_t	empty_group
static _Thread_local unlang_interpret_t *	intp_thread_default
	The default interpreter instance for this thread.
static fr_table_num_ordered_t const	unlang_action_table []
static size_t	unlang_action_table_len = NUM_ELEMENTS(unlang_action_table)
static xlat_arg_parser_t const	unlang_cancel_xlat_args []
static fr_table_num_ordered_t const	unlang_frame_action_table []
static size_t	unlang_frame_action_table_len = NUM_ELEMENTS(unlang_frame_action_table)
static xlat_arg_parser_t const	unlang_interpret_xlat_args []

Detailed Description

Execute compiled unlang structures using an iterative interpret.

Id

3af377b157d5957ba4b3b1dfbae86a800f8ab5f4

Copyright

2006-2016 The FreeRADIUS server project

Definition in file interpret.c.

---

Data Structure Documentation

unlang_variable_ref_t

struct unlang_variable_ref_t

Definition at line 198 of file interpret.c.

Collaboration diagram for unlang_variable_ref_t:

Data Fields
fr_dict_t const *	old_dict	the previous dictionary for the request
request_t *	request	the request

Macro Definition Documentation

DUMP_STACK

#define DUMP_STACK   if (DEBUG_ENABLED5) stack_dump(request)

Definition at line 125 of file interpret.c.

Function Documentation

_local_variables_free()

static int _local_variables_free ( unlang_variable_ref_t *  ref )

static

Definition at line 203 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

frame_dump()

static void frame_dump ( request_t *  request, unlang_stack_frame_t *  frame  )

static

Definition at line 74 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

frame_eval()

static unlang_frame_action_t frame_eval ( request_t *  request, unlang_stack_frame_t *  frame, rlm_rcode_t *  result, int *  priority  )

inlinestatic

Evaluates all the unlang nodes in a section.

This function interprets a list of unlang instructions at a given level using the same stack frame, and pushes additional frames onto the stack as needed.

This function can be seen as moving horizontally.

Parameters

[in]	request	The current request.
[in]	frame	The current stack frame.
[in,out]	result	The current section result.
[in,out]	priority	The current section priority.

Returns

• UNLANG_FRAME_ACTION_NEXT evaluate more instructions in the current stack frame which may not be the same frame as when this function was called.
• UNLANG_FRAME_ACTION_POP the final result has been calculated for this frame.

Definition at line 497 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

instruction_dump()

static void instruction_dump ( request_t *  request, unlang_t const *  instruction  )

static

Definition at line 59 of file interpret.c.

Here is the caller graph for this function:

instruction_retry_handler()

static void instruction_retry_handler ( UNUSED fr_timer_list_t *  tl, UNUSED fr_time_t  now, void *  ctx  )

static

Definition at line 1216 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

instruction_timeout_handler()

static void instruction_timeout_handler ( UNUSED fr_timer_list_t *  tl, UNUSED fr_time_t  now, void *  ctx  )

static

Definition at line 1232 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

result_calculate()

static unlang_frame_action_t result_calculate ( request_t *  request, unlang_stack_frame_t *  frame, rlm_rcode_t *  result, int *  priority  )

inlinestatic

Update the current result after each instruction, and after popping each stack frame.

Parameters

[in]	request	The current request.
[in]	frame	The current stack frame.
[in,out]	result	The current section result.
[in,out]	priority	The current section priority.

Returns

• UNLANG_FRAME_ACTION_NEXT evaluate more instructions.
• UNLANG_FRAME_ACTION_POP the final result has been calculated for this frame.

Definition at line 303 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

stack_dump()

static void stack_dump ( request_t *  request )

static

Definition at line 111 of file interpret.c.

Here is the call graph for this function:

unlang_cancel_event()

static void unlang_cancel_event ( UNUSED fr_timer_list_t *  tl, UNUSED fr_time_t  now, void *  uctx  )

static

Signal the request to stop executing.

The request can't be running at this point because we're in the event loop. This means the request is always in a consistent state when the timeout event fires, even if that's state is waiting on I/O.

Definition at line 1435 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

unlang_cancel_xlat()

static xlat_action_t unlang_cancel_xlat ( TALLOC_CTX *  ctx, fr_dcursor_t *  out, UNUSED xlat_ctx_t const *  xctx, request_t *  request, fr_value_box_list_t *  args  )

static

Allows a request to dynamically alter its own lifetime.

cancel(<timeout>)

If timeout is 0, then the request is immediately cancelled.

Definition at line 1455 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

unlang_interpet_frame_discard()

void unlang_interpet_frame_discard

(

request_t *

request

)

Discard the bottom most frame on the request's stack.

This is used for cleaning up after errors. i.e. the caller uses a push function, and experiences an error and needs to remove the frame that was just pushed.

Definition at line 1730 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

unlang_interpret()

rlm_rcode_t unlang_interpret	(	request_t *	request,
		bool	running
	)

Run the interpreter for a current request.

This function runs the interpreter for a request. It deals with popping stack frames, and calaculating the final result for the frame.

Parameters

[in]	request	to run. If this is an internal request the request may be freed by the interpreter.
[in]	running	Is the interpreter already running.

Returns

The final request rcode.

Definition at line 712 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

unlang_interpret_event_list()

fr_event_list_t * unlang_interpret_event_list

(

request_t *

request

)

Get the event list for the current interpreter.

Definition at line 1757 of file interpret.c.

Here is the caller graph for this function:

unlang_interpret_frame_talloc_ctx()

TALLOC_CTX * unlang_interpret_frame_talloc_ctx

(

request_t *

request

)

Get a talloc_ctx which is valid only for this frame.

Parameters

[in]

request

The current request.

Returns

• a TALLOC_CTX which is valid only for this stack frame

Definition at line 1405 of file interpret.c.

Here is the caller graph for this function:

unlang_interpret_get()

unlang_interpret_t * unlang_interpret_get

(

request_t *

request

)

Get the interpreter set for a request.

Definition at line 1747 of file interpret.c.

Here is the caller graph for this function:

unlang_interpret_get_thread_default()

unlang_interpret_t * unlang_interpret_get_thread_default

(

void

)

Get the default interpreter for this thread.

This allows detached requests to be executed asynchronously

Definition at line 1780 of file interpret.c.

Here is the caller graph for this function:

unlang_interpret_init()

unlang_interpret_t * unlang_interpret_init	(	TALLOC_CTX *	ctx,
		fr_event_list_t *	el,
		unlang_request_func_t *	funcs,
		void *	uctx
	)

Initialize a unlang compiler / interpret.

Parameters

[in]	ctx	to bind lifetime of the interpret to. Shouldn't be any free order issues here as the interpret itself has no state. But event loop should be stopped before freeing the interpret.
[in]	el	for any timer or I/O events.
[in]	funcs	Callbacks to used to communicate request state to our owner.
[in]	uctx	Data to pass to callbacks.

Definition at line 1697 of file interpret.c.

Here is the caller graph for this function:

unlang_interpret_init_global()

int unlang_interpret_init_global

(

TALLOC_CTX *

ctx

)

Definition at line 1787 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

unlang_interpret_is_resumable()

bool unlang_interpret_is_resumable

(

request_t *

request

)

Check if a request as resumable.

Parameters

[in]

request

The current request.

Returns

• true if the request is resumable (i.e. has yielded)
• false if the request is not resumable (i.e. has not yielded)

Definition at line 1342 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

unlang_interpret_mark_runnable()

void unlang_interpret_mark_runnable

(

request_t *

request

)

Mark a request as resumable.

It's not called "unlang_interpret", because it doesn't actually resume the request, it just schedules it for resumption.

Note

that this schedules the request for resumption. It does not immediately start running the request.

Parameters

[in]

request

The current request.

Definition at line 1360 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

unlang_interpret_push()

int unlang_interpret_push	(	request_t *	request,
		unlang_t const *	instruction,
		rlm_rcode_t	default_rcode,
		bool	do_next_sibling,
		bool	top_frame
	)

Push a new frame onto the stack.

Parameters

[in]	request	to push the frame onto.
[in]	instruction	One or more unlang_t nodes describing the operations to execute.
[in]	default_rcode	The default result.
[in]	do_next_sibling	Whether to only execute the first node in the unlang_t program or to execute subsequent nodes.
[in]	top_frame	Return out of the unlang interpret when popping this frame. Hands execution back to whatever called the interpret.

Returns

• 0 on success.
• -1 on call stack too deep.

Definition at line 143 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

unlang_interpret_push_children()

unlang_action_t unlang_interpret_push_children	(	UNUSED rlm_rcode_t *	p_result,
		request_t *	request,
		rlm_rcode_t	default_rcode,
		bool	do_next_sibling
	)

Push the children of the current frame onto a new frame onto the stack.

Parameters

[out]	p_result	set to RLM_MOULDE_FAIL if pushing the children fails
[in]	request	to push the frame onto.
[in]	default_rcode	The default result.
[in]	do_next_sibling	Whether to only execute the first node in the unlang_t program or to execute subsequent nodes.

Returns

• UNLANG_ACTION_PUSHED_CHILD on success.
• UNLANG_ACTION_EXECUTE_NEXT do nothing, but just go to the next sibling instruction
• UNLANG_ACTION_STOP_PROCESSING, fatal error, usually stack overflow.

Definition at line 239 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

unlang_interpret_push_instruction()

int unlang_interpret_push_instruction	(	request_t *	request,
		void *	instruction,
		rlm_rcode_t	default_rcode,
		bool	top_frame
	)

Push an instruction onto the request stack for later interpretation.

Definition at line 949 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

unlang_interpret_push_section()

int unlang_interpret_push_section	(	request_t *	request,
		CONF_SECTION *	cs,
		rlm_rcode_t	default_rcode,
		bool	top_frame
	)

Push a configuration section onto the request stack for later interpretation.

Definition at line 926 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

unlang_interpret_request_detach()

static void unlang_interpret_request_detach ( request_t *  request )

inlinestatic

Tell the interpreter to detach the request.

This function should not be called directly use unlang_interpret_signal(request, FR_SIGNAL_DETACH) instead. This will ensure all frames on the request's stack receive the detach signal.

Definition at line 1037 of file interpret.c.

Here is the caller graph for this function:

unlang_interpret_request_done()

void unlang_interpret_request_done

(

request_t *

request

)

Indicate to the caller of the interpreter that this request is complete.

Definition at line 1006 of file interpret.c.

Here is the caller graph for this function:

unlang_interpret_request_prioritise()

void unlang_interpret_request_prioritise	(	request_t *	request,
		uint32_t	priority
	)

Definition at line 1051 of file interpret.c.

Here is the caller graph for this function:

unlang_interpret_set()

void unlang_interpret_set	(	request_t *	request,
		unlang_interpret_t *	intp
	)

Set a specific interpreter for a request.

Definition at line 1738 of file interpret.c.

Here is the caller graph for this function:

unlang_interpret_set_thread_default()

void unlang_interpret_set_thread_default

(

unlang_interpret_t *

intp

)

Set the default interpreter for this thread.

Definition at line 1769 of file interpret.c.

Here is the caller graph for this function:

unlang_interpret_set_timeout()

int unlang_interpret_set_timeout	(	request_t *	request,
		fr_time_delta_t	timeout
	)

Set a timeout for a request.

The timeout is associated with the current stack frame.

Definition at line 1251 of file interpret.c.

Here is the call graph for this function:

unlang_interpret_signal()

void unlang_interpret_signal	(	request_t *	request,
		fr_signal_t	action
	)

Send a signal (usually stop) to a request.

This is typically called via an "async" action, i.e. an action outside of the normal processing of the request.

Note

This does NOT immediately stop the request, it just deliveres signals, and in the case of a cancel, marks up frames for unwinding and adds it to the runnable queue if it's yielded.

This function should be safe to call anywhere.

Parameters

[in]	request	The current request.
[in]	action	to signal.

Definition at line 1147 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

unlang_interpret_stack_alloc()

void * unlang_interpret_stack_alloc

(

TALLOC_CTX *

ctx

)

Allocate a new unlang stack.

Parameters

[in]

ctx

to allocate stack in.

Returns

• A new stack on success.
• NULL on OOM.

Definition at line 980 of file interpret.c.

Here is the caller graph for this function:

unlang_interpret_stack_depth()

int unlang_interpret_stack_depth

(

request_t *

request

)

Return the depth of the request's stack.

Definition at line 1276 of file interpret.c.

Here is the caller graph for this function:

unlang_interpret_stack_result()

rlm_rcode_t unlang_interpret_stack_result

(

request_t *

request

)

Get the current rcode for the frame.

This can be useful for getting the result of unlang_function_t pushed onto the stack for evaluation.

Parameters

[in]

request

The current request.

Returns

the current rcode for the frame.

Definition at line 1291 of file interpret.c.

Here is the caller graph for this function:

unlang_interpret_stack_result_set()

void unlang_interpret_stack_result_set	(	request_t *	request,
		rlm_rcode_t	rcode
	)

Overwrite the current stack rcode.

Parameters

[in]	request	The current request.
[in]	rcode	to set.

Definition at line 1303 of file interpret.c.

Here is the caller graph for this function:

unlang_request_is_cancelled()

bool unlang_request_is_cancelled

(

request_t const *

request

)

Return whether a request has been cancelled.

Definition at line 1323 of file interpret.c.

Here is the caller graph for this function:

unlang_request_is_done()

bool unlang_request_is_done

(

request_t const *

request

)

Return whether a request has been marked done.

Definition at line 1330 of file interpret.c.

Here is the caller graph for this function:

unlang_request_is_scheduled()

bool unlang_request_is_scheduled

(

request_t const *

request

)

Return whether a request is currently scheduled.

Definition at line 1313 of file interpret.c.

Here is the caller graph for this function:

unlang_stack_signal()

void unlang_stack_signal	(	request_t *	request,
		fr_signal_t	action,
		int	limit
	)

Delivers a frame to one or more frames in the stack.

This is typically called via an "async" action, i.e. an action outside of the normal processing of the request.

For FR_SIGNAL_CANCEL all frames are marked up for cancellation, but the cancellation is handled by the interpret.

Other signal types are delivered immediately, inrrespecitve of whether the request is currently being processed or not.

Signaling stops at the "limit" frame. This is so that keywords such as "timeout" and "limit" can signal frames lower than theirs to stop, but then continue with their own work.

Note

It's better (clearer) to use one of the unwind_* functions unless the entire request is being cancelled.

Parameters

[in]	request	The current request.
[in]	action	to signal.
[in]	limit	the frame at which to stop signaling.

Definition at line 1087 of file interpret.c.

Here is the call graph for this function:

Here is the caller graph for this function:

Variable Documentation

empty_group

unlang_group_t empty_group

static

Initial value:

= {
        .self = {
                .type = UNLANG_TYPE_GROUP,
                .debug_name = "empty-group",
                .actions = {
                        .actions = {
                                MOD_ACTION_RETURN,
                                MOD_ACTION_RETURN,
                                MOD_ACTION_RETURN,
                                MOD_ACTION_RETURN,
                                MOD_ACTION_RETURN,
                                MOD_ACTION_RETURN,
                                MOD_ACTION_RETURN,
                                MOD_ACTION_RETURN,
                                MOD_ACTION_RETURN
                        },
                        .retry = RETRY_INIT,
                },
        },
}

Definition at line 902 of file interpret.c.

intp_thread_default

_Thread_local unlang_interpret_t* intp_thread_default

static

The default interpreter instance for this thread.

Definition at line 40 of file interpret.c.

unlang_action_table

fr_table_num_ordered_t const unlang_action_table[]

static

Initial value:

= {
        { L("calculate-result"),        UNLANG_ACTION_CALCULATE_RESULT },
        { L("next"),                    UNLANG_ACTION_EXECUTE_NEXT },
        { L("pushed-child"),            UNLANG_ACTION_PUSHED_CHILD },
        { L("stop"),                    UNLANG_ACTION_STOP_PROCESSING },
        { L("yield"),                   UNLANG_ACTION_YIELD }
}

Definition at line 42 of file interpret.c.

unlang_action_table_len

size_t unlang_action_table_len = NUM_ELEMENTS(unlang_action_table)

static

Definition at line 49 of file interpret.c.

unlang_cancel_xlat_args

xlat_arg_parser_t const unlang_cancel_xlat_args[]

static

Initial value:

= {
        { .required = false, .single = true, .type = FR_TYPE_TIME_DELTA },
        XLAT_ARG_PARSER_TERMINATOR
}

Definition at line 1420 of file interpret.c.

unlang_frame_action_table

fr_table_num_ordered_t const unlang_frame_action_table[]

static

Initial value:

= {
        { L("pop"),                     UNLANG_FRAME_ACTION_POP         },
        { L("next"),                    UNLANG_FRAME_ACTION_NEXT        },
        { L("yield"),                   UNLANG_FRAME_ACTION_YIELD       }
}

Definition at line 51 of file interpret.c.

unlang_frame_action_table_len

size_t unlang_frame_action_table_len = NUM_ELEMENTS(unlang_frame_action_table)

static

Definition at line 56 of file interpret.c.

unlang_interpret_xlat_args

xlat_arg_parser_t const unlang_interpret_xlat_args[]

static

Initial value:

= {
        { .required = true, .single = true, .type = FR_TYPE_STRING },
        XLAT_ARG_PARSER_TERMINATOR
}

Definition at line 1529 of file interpret.c.