@ -30,23 +30,23 @@
namespace srslte {
enum class proc_state_t { on_going , success , error , inactive } ;
enum class proc_outcome_t { repeat , yield , success , error } ;
/**************************************************************************************
* helper functions for
* helper functions for method optional overloading
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
namespace detail {
// used by proc_ manager to call proc finally () method only if it exists
template < class T >
auto optional_ comple te( T * obj , int is_success ) - > decltype ( obj - > on_complete ( is_success ) )
// used by proc_ t<T> to call T::then () method only if it exists
template < typename T , typename ProcResult >
auto optional_ th en ( T * obj , const ProcResult & result ) - > decltype ( obj - > then ( result ) )
{
obj - > on_complete( is_success ) ;
obj - > then( result ) ;
}
inline auto optional_ comple te( . . . ) - > void
inline auto optional_ th en ( . . . ) - > void
{
// do nothing
}
// used by proc_t<T> to call proc T::clear() method only if it exists
template < class T >
auto optional_clear ( T * obj ) - > decltype ( obj - > clear ( ) )
{
@ -56,27 +56,34 @@ inline auto optional_clear(...) -> void
{
// do nothing
}
template < class T >
auto get_result_type ( const T & obj ) - > decltype ( obj . get_result ( ) ) ;
inline auto get_result_type ( . . . ) - > void ;
} // namespace detail
/**************************************************************************************
* class : callback_list_t
* class : callback_group_t < Args . . . >
* Bundles several callbacks with callable interface " void(Args...) " .
* Calls to operator ( Args & & . . . ) call all the registered callbacks .
* Two methods to register a callback - call it once , or always call it .
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
template < typename Func >
class callback_ list _t
template < typename . . . Args >
class callback_ group _t
{
public :
using id_type = uint32_t ;
using callback_t = Func ;
// register new callbacks
id_type call_once ( callback_t f_ )
using callback_id_t = uint32_t ;
using callback_t = std : : function < void ( Args . . . ) > ;
//! register callback, that gets called once
callback_id_t on_next_call ( callback_t f_ )
{
uint32_t idx = get_new_callback ( ) ;
func_list [ idx ] . func = std : : move ( f_ ) ;
func_list [ idx ] . call_always = false ;
return idx ;
}
id_type call_always ( callback_t f_ )
callback_id_t on_every_call ( callback_t f_ )
{
uint32_t idx = get_new_callback ( ) ;
func_list [ idx ] . func = std : : move ( f_ ) ;
@ -85,11 +92,12 @@ public:
}
// call all callbacks
void run ( bool is_success )
template < typename . . . ArgsRef >
void operator ( ) ( const ArgsRef & . . . args )
{
for ( auto & f : func_list ) {
if ( f . active ) {
f . func ( is_success ) ;
f . func ( args. . . ) ;
if ( not f . call_always ) {
f . active = false ;
}
@ -112,19 +120,89 @@ private:
struct call_item_t {
bool active ;
std : : function < void ( bool ) > func ;
callback_t func ;
bool call_always ;
} ;
std : : vector < call_item_t > func_list ;
} ;
/**************************************************************************************
* class : proc_itf_t
* class : proc_result_t
* Stores the result of a procedure run . Can optionally contain a value T , in case of a
* successful run .
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
namespace detail {
struct proc_result_base_t {
bool is_success ( ) const { return state = = result_state_t : : value ; }
bool is_error ( ) const { return state = = result_state_t : : error ; }
bool is_complete ( ) const { return state ! = result_state_t : : none ; }
void set_val ( ) { state = result_state_t : : value ; }
void set_error ( ) { state = result_state_t : : error ; }
void clear ( ) { state = result_state_t : : none ; }
protected :
enum class result_state_t { none , value , error } state = result_state_t : : none ;
} ;
} // namespace detail
template < typename T >
struct proc_result_t : public detail : : proc_result_base_t {
const T * value ( ) const { return state = = result_state_t : : value ? & t : nullptr ; }
void set_val ( const T & t_ )
{
proc_result_base_t : : set_val ( ) ;
t = t_ ;
}
template < typename Proc >
void extract_val ( Proc & p )
{
set_val ( p . get_result ( ) ) ;
}
protected :
T t ;
} ;
template < >
struct proc_result_t < void > : public detail : : proc_result_base_t {
template < typename Proc >
void extract_val ( Proc & p )
{
set_val ( ) ;
}
} ;
/**************************************************************************************
* class : proc_future_t
* Contains a pointer to the result of a procedure run . This pointer gets updated with
* the actual result once the procedure completes .
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
template < typename ResultType >
class proc_future_t
{
public :
proc_future_t ( ) = default ;
explicit proc_future_t ( const std : : shared_ptr < proc_result_t < ResultType > > & p_ ) : ptr ( p_ ) { }
bool is_error ( ) const { return ptr - > is_error ( ) ; }
bool is_success ( ) const { return ptr - > is_success ( ) ; }
bool is_complete ( ) const { return ptr - > is_complete ( ) ; }
const ResultType * value ( ) const { return is_success ( ) ? ptr - > value ( ) : nullptr ; }
private :
std : : shared_ptr < proc_result_t < ResultType > > ptr ;
} ;
using proc_future_state_t = proc_future_t < void > ;
/**************************************************************************************
* class : proc_base_t
* Provides a polymorphic interface for resumable procedures . This base can then be used
* by a procedure manager container via the virtual method " proc_itf_t::run() " .
* With methods :
* - run ( ) - executes a procedure , returning true if the procedure is still running
* or false , if it has completed
* by a " proc_manager_list_t " via the virtual method " proc_base_t::run() " .
* With public methods :
* - run ( ) - executes proc_t < T > : : step ( ) , and updates procedure state .
* - is_busy ( ) / is_idle ( ) - tells if procedure is currently running . Busy procedures
* cannot be re - launched
* - then ( ) - called automatically when a procedure has finished . Useful for actions
* upon procedure completion , like sending back a response or logging .
* With protected methods :
* - step ( ) - method overriden by child class that will be called by run ( ) . step ( )
* executes a procedure " action " based on its current internal state ,
* and return a proc_outcome_t variable with possible values :
@ -133,77 +211,88 @@ private:
* recall step ( ) again ( probably the procedure state has changed )
* - error - the procedure has finished unsuccessfully
* - success - the procedure has completed successfully
* - finally ( ) - called automatically when a procedure has finished . Useful for actions
* upon procedure completion , like sending back a response .
* - set_proc_state ( ) / is_ # ( ) - setter and getters for current procedure state
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
class proc_ manager_itf _t
class proc_base_t
{
public :
virtual bool run ( ) = 0 ;
virtual ~ proc_manager_itf_t ( ) = default ;
} ;
virtual ~ proc_base_t ( ) = default ;
template < typename T >
struct proc_result_t ;
/**************************************************************************************
* class : proc_manager_t < T >
* Manages the lifetime , of a procedure T , including its alloc , launching ,
* and reset back to initial , uninit state once the procedure has been
* completed and the user has extracted its results .
* Every procedure starts in inactive state , and finishes with success or error .
* Can only be re - launched when a procedure T becomes inactive .
* It uses a unique_ptr < T > to allow the use of procedures that are forward declared .
* It provides the following methods :
* - run ( ) - calls T : : step ( ) and update the procedure state .
* - launch ( ) - initializes the procedure T by calling T : : init ( . . . ) . Handles the case
* of failed initialization , and forbids the initialization of procedures
* that are already active .
* - pop ( ) - extracts the result of the procedure if it has finished , and sets
* proc_t < T > back to inactive
* - trigger_event ( Event ) - used for handling external events . The procedure T will
* have to define a method " trigger_event(Event) " as well ,
* specifying how each event type should be handled .
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
template < class T >
class proc_t final : public proc_manager_itf_t
{
using complete_callback_list_t = callback_list_t < std : : function < void ( bool ) > > ;
public :
template < typename . . . Args >
explicit proc_t ( Args & & . . . args ) : proc_impl_ptr ( new T ( std : : forward < Args > ( args ) . . . ) )
//! common proc::run() interface. Returns true if procedure is still running
bool run ( )
{
proc_outcome_t outcome = proc_outcome_t : : repeat ;
while ( is_busy ( ) and outcome = = proc_outcome_t : : repeat ) {
outcome = step ( ) ;
handle_outcome ( outcome ) ;
}
return is_busy ( ) ;
}
//! interface to check if proc is still running
bool is_busy ( ) const { return proc_state = = proc_status_t : : on_going ; }
bool is_idle ( ) const { return proc_state = = proc_status_t : : idle ; }
bool run ( ) override
protected :
enum class proc_status_t { idle , on_going } ;
virtual proc_outcome_t step ( ) = 0 ;
virtual void run_then ( bool is_success ) = 0 ;
void handle_outcome ( proc_outcome_t outcome )
{
proc_outcome_t outcome = proc_outcome_t : : repeat ;
while ( is_running ( ) and outcome = = proc_outcome_t : : repeat ) {
outcome = proc_impl_ptr - > step ( ) ;
handle_outcome ( outcome ) ;
if ( outcome = = proc_outcome_t : : error or outcome = = proc_outcome_t : : success ) {
bool success = outcome = = proc_outcome_t : : success ;
run_then ( success ) ;
}
return is_running ( ) ;
}
void clear ( )
proc_status_t proc_state = proc_status_t : : idle ;
} ;
/**************************************************************************************
* class : proc_t < T , ResultType >
* Manages the lifetime of a procedure of type T , including its alloc , launching ,
* and reset back to " inactive " state once the procedure has been completed .
* The result of a procedure run is of type " proc_result_t<ResultType> " . ResultType has
* to coincide with the type returned by the method " T::get_result() " .
* There are three main ways to use the result of a procedure run :
* - " T::then(const proc_result_t<T>&) " - method in T that runs on completion , and
* gets as argument the result of the run
* - " proc_t<T>::get_future() " - returns a proc_future_t < T > which the user can use
* directly to check the result of a run
* - " proc_t<T>::then/then_always() " - provide dynamically a continuation task , for
* instance , by providing a lambda
* It uses a unique_ptr < T > to allow the use of procedures that are forward declared .
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
// Implementation of the Procedure Manager functionality, including launching, trigger events, clearing
template < class T , typename ResultType = void >
class proc_t : public proc_base_t
{
public :
// cannot derive automatically this type
using result_type = ResultType ;
using proc_result_type = proc_result_t < result_type > ;
using proc_future_type = proc_future_t < result_type > ;
using then_callback_list_t = callback_group_t < proc_result_type > ;
using callback_t = typename then_callback_list_t : : callback_t ;
using callback_id_t = typename then_callback_list_t : : callback_id_t ;
template < typename . . . Args >
explicit proc_t ( Args & & . . . args ) : proc_ptr ( new T ( std : : forward < Args > ( args ) . . . ) )
{
// resets procedure and sets proc_t back to inactive
detail : : optional_clear ( proc_impl_ptr . get ( ) ) ;
proc_state = proc_state_t : : inactive ;
static_assert ( std : : is_same < result_type , decltype ( detail : : get_result_type ( std : : declval < T > ( ) ) ) > : : value ,
" The types \" proc_t::result_type \" and the return of T::get_result() have to match " ) ;
}
const T * get ( ) const { return proc_impl_ptr . get ( ) ; }
bool is_active ( ) const { return proc_state ! = proc_state_t : : inactive ; }
bool is_complete ( ) const { return proc_state = = proc_state_t : : success or proc_state = = proc_state_t : : error ; }
T * release ( ) { return proc_impl_ptr . release ( ) ; }
const T * get ( ) const { return proc_ptr . get ( ) ; }
T * release ( ) { return proc_ptr . release ( ) ; }
//! method to handle external events. "T" must have the method "T::react(const Event&)" for the trigger to take effect
template < class Event >
void trigger_event ( Event & & e )
void trigger ( Event & & e )
{
if ( is_running ( ) ) {
proc_outcome_t outcome = proc_impl_ptr - > trigger_event ( std : : forward < Event > ( e ) ) ;
if ( is_ busy ( ) ) {
proc_outcome_t outcome = proc_ ptr- > reac t( std : : forward < Event > ( e ) ) ;
handle_outcome ( outcome ) ;
if ( outcome = = proc_outcome_t : : repeat ) {
run ( ) ;
@ -211,87 +300,106 @@ public:
}
}
//! returns an object which the user can use to check if the procedure has ended.
proc_future_type get_future ( )
{
if ( future_result = = nullptr ) {
future_result = std : : make_shared < proc_result_type > ( proc_result ) ;
}
return proc_future_type { future_result } ;
}
//! methods to schedule continuation tasks
callback_id_t then ( const callback_t & c ) { return complete_callbacks . on_next_call ( c ) ; }
callback_id_t then_always ( const callback_t & c ) { return complete_callbacks . on_every_call ( c ) ; }
//! launch a procedure, returning true if successful or running and false if it error or it failed to launch
template < class . . . Args >
bool launch ( Args & & . . . args )
{
if ( is_active ( ) ) {
// if already active
if ( is_busy ( ) ) {
return false ;
}
proc_state = proc_state_t : : on_going ;
proc_outcome_t init_ret = proc_impl_ptr - > init ( std : : forward < Args > ( args ) . . . ) ;
proc_state = proc_base_t : : proc_status_t : : on_going ;
proc_outcome_t init_ret = proc_ptr - > init ( std : : forward < Args > ( args ) . . . ) ;
handle_outcome ( init_ret ) ;
switch ( init_ret ) {
case proc_outcome_t : : error :
handle_outcome ( init_ret ) ;
clear ( ) ;
return false ;
case proc_outcome_t : : success :
handle_outcome ( init_ret ) ;
// does not reset, and returns true
break ;
case proc_outcome_t : : repeat :
run ( ) ; // call run right away
break ;
case proc_outcome_t : : yield :
default :
break ;
}
return true ;
}
proc_result_t < T > pop ( ) ;
protected :
proc_outcome_t step ( ) final { return proc_ptr - > step ( ) ; }
// on_complete interface
complete_callback_list_t : : id_type then ( const complete_callback_list_t : : callback_t & c )
void run_then ( bool is_success ) final
{
return complete_callbacks . call_once ( c ) ;
}
complete_callback_list_t : : id_type then_always ( const complete_callback_list_t : : callback_t & c )
{
return complete_callbacks . call_always ( c ) ;
}
// update result state
if ( is_success ) {
proc_result . extract_val ( * proc_ptr ) ;
} else {
proc_result . set_error ( ) ;
}
// call T::then() if it exists
detail : : optional_then ( proc_ptr . get ( ) , proc_result ) ;
// signal continuations
complete_callbacks ( proc_result ) ;
// propagate proc_result to future if it exists, and release future
if ( future_result ! = nullptr ) {
* future_result = proc_result ;
future_result . reset ( ) ;
}
// reset the current result, to prepare it for a new run.
proc_result . clear ( ) ;
// back to inactive
detail : : optional_clear ( proc_ptr . get ( ) ) ;
proc_state = proc_status_t : : idle ;
}
std : : unique_ptr < T > proc_ptr ;
proc_result_type proc_result ;
std : : shared_ptr < proc_result_type > future_result ; //! used if get_future() itf is used.
then_callback_list_t complete_callbacks ;
} ;
protected :
friend proc_result_t < T > ;
bool is_running ( ) const { return proc_state = = proc_state_t : : on_going ; }
void handle_outcome ( proc_outcome_t outcome )
/**************************************************************************************
* class : event_handler_t < Args . . . >
* Bundles several proc_managers together with same trigger ( Args . . . ) itf .
* Once trigger ( . . . ) is called , all registered proc_managers get triggered
* as well .
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
// NOTE: Potential improvements: a method "trigger_during_this_run" that unregisters the handler
// once the procedure run is finished.
template < typename EventType >
class event_handler_t
{
public :
using callback_id_t = typename callback_group_t < EventType > : : callback_id_t ;
template < typename Proc , typename ResultType >
callback_id_t on_next_trigger ( proc_t < Proc , ResultType > & p )
{
if ( outcome = = proc_outcome_t : : error or outcome = = proc_outcome_t : : success ) {
bool success = outcome = = proc_outcome_t : : success ;
proc_state = success ? proc_state_t : : success : proc_state_t : : error ;
detail : : optional_complete ( proc_impl_ptr . get ( ) , success ) ;
complete_callbacks . run ( success ) ;
}
return callbacks . on_next_call ( [ & p ] ( EventType & & ev ) { p . trigger ( std : : forward < EventType > ( ev ) ) ; } ) ;
}
proc_state_t proc_state = proc_state_t : : inactive ;
std : : unique_ptr < T > proc_impl_ptr ;
complete_callback_list_t complete_callbacks ;
} ;
template < typename T >
struct proc_result_t {
explicit proc_result_t ( proc_t < T > * parent_ ) : parent ( parent_ ) { }
~ proc_result_t ( )
template < typename Proc , typename ResultType >
callback_id_t on_every_trigger ( proc_t < Proc , ResultType > & p )
{
if ( parent - > is_complete ( ) ) {
parent - > clear ( ) ;
}
return callbacks . on_every_call ( [ & p ] ( EventType & & ev ) { p . trigger ( std : : forward < EventType > ( ev ) ) ; } ) ;
}
const T * proc ( ) const { return parent - > is_complete ( ) ? parent - > proc_impl_ptr . get ( ) : nullptr ; }
bool is_success ( ) const { return parent - > proc_state = = proc_state_t : : success ; }
bool is_error ( ) const { return parent - > proc_state = = proc_state_t : : error ; }
bool is_complete ( ) const { return parent - > is_complete ( ) ; }
void trigger ( EventType & & ev ) { callbacks ( std : : forward < EventType > ( ev ) ) ; }
private :
proc_t< T > * parent ;
callback_group_t< EventType > callbacks ;
} ;
template < typename T >
proc_result_t < T > proc_t < T > : : pop ( )
{
return proc_result_t < T > { this } ;
}
/**************************************************************************************
* class : func_proc_t
* A proc used to store lambda functions and other function pointers as a step ( )
@ -308,106 +416,52 @@ private:
std : : function < proc_outcome_t ( ) > step_func ;
} ;
/**************************************************************************************
* class : query_proc_t
* A helper proc_impl_t whose step ( ) / finally ( ) are no op , but has a trigger_event ( ) that
* signals that the method has finished and store a result of type OutcomeType .
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
template < class OutcomeType >
class query_proc_t
{
public :
proc_outcome_t init ( ) { return proc_outcome_t : : yield ; }
proc_outcome_t step ( ) { return proc_outcome_t : : yield ; }
proc_outcome_t trigger_event ( const OutcomeType & outcome_ )
{
outcome = outcome_ ;
return proc_outcome_t : : success ;
}
const OutcomeType & result ( ) const { return outcome ; }
private :
OutcomeType outcome ;
} ;
/**************************************************************************************
* class : proc_manager_list_t
* Stores procedure managers and , when run ( ) is called , calls sequentially all
* the stored procedures run ( ) method , and removes the procedures if they have
* .
* There are differen t ways to add a procedure to the list :
* already completed .
* There are two ways to add a procedure to the list :
* - add_proc ( . . . ) - adds a proc_t < T > , and once the procedure has completed , takes it
* out of the container without resetting it back to its initial state
* or deleting . This is useful , if the user wants to extract the
* procedure result after it has been taken off the manager list .
* " proc " variable has to outlive its completion
* - consume_proc ( . . . ) - receives a proc_t < T > as a rvalue , and calls the proc_t < T >
* destructor once the procedure has ended . Useful , for procedures
* for which the user is not interested in the result , or reusing
* - defer_proc ( . . . ) - same as add_proc ( . . . ) , but once the procedure has finished , it
* automatically sets the procedure back to its initial state .
* Useful if the user is not interested in handling the result
* - defer_task ( . . . ) - same as consume_proc ( . . . ) but takes a function pointer that
* out of the container . In case a r - value ref is passed , this class
* calls its destructor .
* - add_task ( . . . ) - same as add_proc ( . . . ) but takes a function pointer that
* specifies a proc_impl_t step ( ) function
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
class proc_manager_list_t
{
using proc_deleter_t = std : : function < void ( proc_manager_itf_t * ) > ;
using proc_obj_t = std : : unique_ptr < proc_manager_itf_t , proc_deleter_t > ;
template < typename T >
struct recycle_deleter_t {
void operator ( ) ( proc_manager_itf_t * p )
{
if ( p ! = nullptr ) {
T * Tp = static_cast < T * > ( p ) ;
Tp - > clear ( ) ;
// just resets back to inactive, and does not dealloc
}
}
} ;
using proc_deleter_t = std : : function < void ( proc_base_t * ) > ;
using proc_obj_t = std : : unique_ptr < proc_base_t , proc_deleter_t > ;
public :
template < typename T >
void add_proc ( proc_t < T > & proc )
{
if ( proc . is_complete ( ) ) {
return ;
}
proc_obj_t ptr ( & proc , [ ] ( proc_manager_itf_t * p ) { /* do nothing */ } ) ;
proc_list . push_back ( std : : move ( ptr ) ) ;
}
template < class T >
void consume_proc ( proc_t < T > & & proc )
template < typename T , typename ResultType >
void add_proc ( proc_t < T , ResultType > & proc )
{
if ( proc . is_ complet e( ) ) {
if ( proc . is_idle ( ) ) {
return ;
}
proc_obj_t ptr ( new proc_t < T > ( std : : move ( proc ) ) , std : : default_delete < proc_manager_itf_t > ( ) ) ;
proc_obj_t ptr ( & proc , [ ] ( proc_base_t * p ) { /* do nothing */ } ) ;
proc_list . push_back ( std : : move ( ptr ) ) ;
}
template < typename T >
void defer_proc ( proc_t < T > & proc )
// since it receives a r-value, it calls the default destructor
template < class T , typename ResultType >
void add_proc ( proc_t < T , ResultType > & & proc )
{
if ( proc . is_complete ( ) ) {
proc . clear ( ) ;
if ( proc . is_idle ( ) ) {
return ;
}
proc_obj_t ptr ( & proc , recycle_deleter_t < proc_t < T > > ( ) ) ;
proc_obj_t ptr ( new proc_t < T , ResultType > ( std : : move ( proc ) ) , std : : default_delete < proc_base_t > ( ) ) ;
proc_list . push_back ( std : : move ( ptr ) ) ;
}
bool defer _task( std : : function < proc_outcome_t ( ) > step_func )
bool add _task( std : : function < proc_outcome_t ( ) > step_func )
{
proc_t < func_proc_t > proc ( std : : move ( step_func ) ) ;
if ( not proc . launch ( ) ) {
return false ;
}
consume _proc( std : : move ( proc ) ) ;
add _proc( std : : move ( proc ) ) ;
return true ;
}
Francisco Paisana
5 years ago
committed by
Andre Puschmann