The FreeRADIUS server  $Id: 15bac2a4c627c01d1aa2047687b3418955ac7f00 $
Data Structures | Macros | Functions | Variables
interpret.c File Reference

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

#include <freeradius-devel/server/base.h>
#include <freeradius-devel/server/modpriv.h>
#include <freeradius-devel/unlang/xlat_func.h>
#include <freeradius-devel/unlang/xlat.h>
#include <freeradius-devel/util/time.h>
#include "interpret_priv.h"
#include "module_priv.h"
#include "parallel_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)
 
#define UNWIND_FLAG_DUMP(attrib)    if (unwind & attrib) strcat(buf, #attrib" ")
 

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. More...
 
static void instruction_dump (request_t *request, unlang_t const *instruction)
 
static void instruction_timeout_handler (UNUSED fr_event_list_t *el, 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. More...
 
static void stack_dump (request_t *request)
 
static char * stack_unwind_flag_dump (uint8_t unwind)
 
static void unlang_cancel_event (UNUSED fr_event_list_t *el, UNUSED fr_time_t now, void *uctx)
 Signal the request to stop executing. More...
 
static xlat_action_t unlang_cancel_never_run (UNUSED TALLOC_CTX *ctx, UNUSED fr_dcursor_t *out, UNUSED xlat_ctx_t const *xctx, UNUSED request_t *request, UNUSED fr_value_box_list_t *in)
 
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. More...
 
void unlang_frame_signal (request_t *request, fr_signal_t action, int limit)
 Send a signal (usually stop) to a request. More...
 
void unlang_interpet_frame_discard (request_t *request)
 Discard the bottom most frame on the request's stack. More...
 
rlm_rcode_t unlang_interpret (request_t *request)
 Run the interpreter for a current request. More...
 
fr_event_list_tunlang_interpret_event_list (request_t *request)
 Get the event list for the current interpreter. More...
 
TALLOC_CTX * unlang_interpret_frame_talloc_ctx (request_t *request)
 Get a talloc_ctx which is valid only for this frame. More...
 
unlang_interpret_tunlang_interpret_get (request_t *request)
 Get the interpreter set for a request. More...
 
unlang_interpret_tunlang_interpret_get_thread_default (void)
 Get the default interpreter for this thread. More...
 
unlang_interpret_tunlang_interpret_init (TALLOC_CTX *ctx, fr_event_list_t *el, unlang_request_func_t *funcs, void *uctx)
 Initialize a unlang compiler / interpret. More...
 
int unlang_interpret_init_global (TALLOC_CTX *ctx)
 
bool unlang_interpret_is_resumable (request_t *request)
 Check if a request as resumable. More...
 
void unlang_interpret_mark_runnable (request_t *request)
 Mark a request as resumable. More...
 
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. More...
 
unlang_action_t unlang_interpret_push_children (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. More...
 
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. More...
 
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. More...
 
static void unlang_interpret_request_detach (request_t *request)
 
void unlang_interpret_request_done (request_t *request)
 Indicate to the caller of the interpreter that this request is complete. More...
 
static void unlang_interpret_request_stop (request_t *request)
 
void unlang_interpret_set (request_t *request, unlang_interpret_t *intp)
 Set a specific interpreter for a request. More...
 
void unlang_interpret_set_thread_default (unlang_interpret_t *intp)
 Set the default interpreter for this thread. More...
 
void unlang_interpret_signal (request_t *request, fr_signal_t action)
 Send a signal (usually stop) to a request. More...
 
void * unlang_interpret_stack_alloc (TALLOC_CTX *ctx)
 Allocate a new unlang stack. More...
 
int unlang_interpret_stack_depth (request_t *request)
 Return the depth of the request's stack. More...
 
rlm_rcode_t unlang_interpret_stack_result (request_t *request)
 Get the current rcode for the frame. More...
 
void unlang_interpret_stack_result_set (request_t *request, rlm_rcode_t rcode)
 Overwrite the current stack rcode. More...
 
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. More...
 
bool unlang_request_is_cancelled (request_t const *request)
 Return whether a request has been cancelled. More...
 
bool unlang_request_is_scheduled (request_t const *request)
 Return whether a request is currently scheduled. More...
 

Variables

static unlang_group_t empty_group
 
static _Thread_local unlang_interpret_tintp_thread_default
 The default interpreter instance for this thread. More...
 
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
3873376d28a586241b1b9a6b0824f3e7e97f264c

Definition in file interpret.c.


Data Structure Documentation

◆ unlang_variable_ref_t

struct unlang_variable_ref_t

Definition at line 215 of file interpret.c.

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Data Fields
fr_dict_t const * dict
request_t * request

Macro Definition Documentation

◆ DUMP_STACK

#define DUMP_STACK   if (DEBUG_ENABLED5) stack_dump(request)

Definition at line 143 of file interpret.c.

◆ UNWIND_FLAG_DUMP

#define UNWIND_FLAG_DUMP (   attrib)     if (unwind & attrib) strcat(buf, #attrib" ")

Function Documentation

◆ _local_variables_free()

static int _local_variables_free ( unlang_variable_ref_t ref)
static

Definition at line 220 of file interpret.c.

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◆ frame_dump()

static void frame_dump ( request_t request,
unlang_stack_frame_t frame 
)
static

Definition at line 75 of file interpret.c.

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◆ 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.

Parameters
[in]requestThe current request.
[in]frameThe current stack frame.
[in,out]resultThe current section result.
[in,out]priorityThe 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 516 of file interpret.c.

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◆ instruction_dump()

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

Definition at line 60 of file interpret.c.

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◆ instruction_timeout_handler()

static void instruction_timeout_handler ( UNUSED fr_event_list_t el,
UNUSED fr_time_t  now,
void *  ctx 
)
static

Definition at line 1244 of file interpret.c.

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◆ 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]requestThe current request.
[in]frameThe current stack frame.
[in,out]resultThe current section result.
[in,out]priorityThe 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 307 of file interpret.c.

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◆ stack_dump()

static void stack_dump ( request_t request)
static

Definition at line 129 of file interpret.c.

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◆ stack_unwind_flag_dump()

static char* stack_unwind_flag_dump ( uint8_t  unwind)
static

Definition at line 106 of file interpret.c.

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◆ unlang_cancel_event()

static void unlang_cancel_event ( UNUSED fr_event_list_t el,
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 1414 of file interpret.c.

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◆ unlang_cancel_never_run()

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

Definition at line 1429 of file interpret.c.

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◆ 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 1443 of file interpret.c.

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◆ unlang_frame_signal()

void unlang_frame_signal ( request_t request,
fr_signal_t  action,
int  limit 
)

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.

If there is no unlang_module_signal_t callback defined, the action is ignored.

The 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.

Parameters
[in]requestThe current request.
[in]actionto signal.
[in]limitthe frame at which to stop signaling.

Definition at line 1130 of file interpret.c.

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◆ 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 1718 of file interpret.c.

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◆ unlang_interpret()

rlm_rcode_t unlang_interpret ( request_t request)

Run the interpreter for a current request.

Parameters
[in]requestto run. If this is an internal request the request may be freed by the interpreter.
Returns
The final request rcode.

Definition at line 760 of file interpret.c.

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◆ 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 1745 of file interpret.c.

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◆ 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]requestThe current request.
Returns
  • a TALLOC_CTX which is valid only for this stack frame

Definition at line 1384 of file interpret.c.

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◆ unlang_interpret_get()

unlang_interpret_t* unlang_interpret_get ( request_t request)

Get the interpreter set for a request.

Definition at line 1735 of file interpret.c.

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◆ 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 1768 of file interpret.c.

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◆ 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]ctxto 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]elfor any timer or I/O events.
[in]funcsCallbacks to used to communicate request state to our owner.
[in]uctxData to pass to callbacks.

Definition at line 1684 of file interpret.c.

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◆ unlang_interpret_init_global()

int unlang_interpret_init_global ( TALLOC_CTX *  ctx)

Definition at line 1775 of file interpret.c.

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◆ unlang_interpret_is_resumable()

bool unlang_interpret_is_resumable ( request_t request)

Check if a request as resumable.

Parameters
[in]requestThe 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 1322 of file interpret.c.

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◆ 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]requestThe current request.

Definition at line 1340 of file interpret.c.

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◆ 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]requestto push the frame onto.
[in]instructionOne or more unlang_t nodes describing the operations to execute.
[in]default_rcodeThe default result.
[in]do_next_siblingWhether to only execute the first node in the unlang_t program or to execute subsequent nodes.
[in]top_frameReturn 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 161 of file interpret.c.

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◆ unlang_interpret_push_children()

unlang_action_t unlang_interpret_push_children ( 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_resultset to RLM_MOULDE_FAIL if pushing the children fails
[in]requestto push the frame onto.
[in]default_rcodeThe default result.
[in]do_next_siblingWhether 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 243 of file interpret.c.

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◆ 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 1005 of file interpret.c.

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◆ 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 982 of file interpret.c.

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◆ unlang_interpret_request_detach()

static void unlang_interpret_request_detach ( request_t request)
inlinestatic

Definition at line 1101 of file interpret.c.

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◆ 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 1062 of file interpret.c.

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◆ unlang_interpret_request_stop()

static void unlang_interpret_request_stop ( request_t request)
inlinestatic

Definition at line 1087 of file interpret.c.

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◆ unlang_interpret_set()

void unlang_interpret_set ( request_t request,
unlang_interpret_t intp 
)

Set a specific interpreter for a request.

Definition at line 1726 of file interpret.c.

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◆ 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 1757 of file interpret.c.

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◆ 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.

If there is no unlang_module_signal_t callback defined, the action is ignored.

Parameters
[in]requestThe current request.
[in]actionto signal.

Definition at line 1184 of file interpret.c.

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◆ unlang_interpret_stack_alloc()

void* unlang_interpret_stack_alloc ( TALLOC_CTX *  ctx)

Allocate a new unlang stack.

Parameters
[in]ctxto allocate stack in.
Returns
  • A new stack on success.
  • NULL on OOM.

Definition at line 1036 of file interpret.c.

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◆ unlang_interpret_stack_depth()

int unlang_interpret_stack_depth ( request_t request)

Return the depth of the request's stack.

Definition at line 1263 of file interpret.c.

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◆ 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]requestThe current request.
Returns
the current rcode for the frame.

Definition at line 1278 of file interpret.c.

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◆ 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]requestThe current request.
[in]rcodeto set.

Definition at line 1290 of file interpret.c.

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◆ unlang_request_is_cancelled()

bool unlang_request_is_cancelled ( request_t const *  request)

Return whether a request has been cancelled.

Definition at line 1310 of file interpret.c.

◆ unlang_request_is_scheduled()

bool unlang_request_is_scheduled ( request_t const *  request)

Return whether a request is currently scheduled.

Definition at line 1300 of file interpret.c.

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Variable Documentation

◆ empty_group

unlang_group_t empty_group
static
Initial value:
= {
.self = {
.debug_name = "empty-group",
.actions = {
.actions = {
},
.retry = RETRY_INIT,
},
},
}
#define MOD_ACTION_RETURN
Definition: unlang_priv.h:44
@ UNLANG_TYPE_GROUP
Grouping section.
Definition: unlang_priv.h:58
#define RETRY_INIT
Definition: retry.h:39

Definition at line 958 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("unwind"), UNLANG_ACTION_UNWIND },
{ L("calculate-result"), UNLANG_ACTION_CALCULATE_RESULT },
{ L("pushed-child"), UNLANG_ACTION_PUSHED_CHILD },
{ L("yield"), UNLANG_ACTION_YIELD }
}
@ UNLANG_ACTION_UNWIND
Break out of the current group.
Definition: action.h:41
@ UNLANG_ACTION_PUSHED_CHILD
unlang_t pushed a new child onto the stack, execute it instead of continuing.
Definition: action.h:39
@ UNLANG_ACTION_EXECUTE_NEXT
Execute the next unlang_t.
Definition: action.h:38
@ UNLANG_ACTION_STOP_PROCESSING
Break out of processing the current request (unwind).
Definition: action.h:43
@ UNLANG_ACTION_CALCULATE_RESULT
Calculate a new section rlm_rcode_t value.
Definition: action.h:37
@ UNLANG_ACTION_YIELD
Temporarily pause execution until an event occurs.
Definition: action.h:42
#define L(_str)
Helper for initialising arrays of string literals.
Definition: build.h:207

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 50 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 },
}
@ FR_TYPE_TIME_DELTA
A period of time measured in nanoseconds.
Definition: merged_model.c:113
#define XLAT_ARG_PARSER_TERMINATOR
Definition: xlat.h:166

Definition at line 1399 of file interpret.c.

◆ unlang_frame_action_table

fr_table_num_ordered_t const unlang_frame_action_table[]
static
Initial value:
= {
}
@ UNLANG_FRAME_ACTION_POP
Pop the current frame, and check the next one further up in the stack for what to do next.
Definition: unlang_priv.h:94
@ UNLANG_FRAME_ACTION_YIELD
Temporarily return control back to the caller on the C stack.
Definition: unlang_priv.h:98
@ UNLANG_FRAME_ACTION_NEXT
Process the next instruction at this level.
Definition: unlang_priv.h:97

Definition at line 52 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 57 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 },
}
@ FR_TYPE_STRING
String of printable characters.
Definition: merged_model.c:83

Definition at line 1516 of file interpret.c.