roland/xo-alloc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

initial implementation

Browse source
This commit is contained in:
Roland Conybeare 2023-10-11 17:46:24 -04:00
commit 0157f8dc04
12 changed files with 703 additions and 658 deletions
Download patch file Download diff file Expand all files Collapse all files

208
include/xo/reactor/ReactorSource.hpp
View file

@ -7,124 +7,124 @@
#include <cstdint>
namespace xo {
namespace reactor {
class Reactor;
namespace reactor {
class Reactor;
/* abstract api for a source of events.
* Event representation is left open: Sources and Sinks
* need to have compatible event representations,
* and coordination is left to such (Source, Sink) pairs.
*
* Source->Sink activity may be expected to be mediated by a reactor,
* that implements the Reactor api.
*
* At any time, A Source can be associated with at most one reactor.
* Sources are informed of Reactor<->Source association being
* formed/broken by the
* .notify_reactor_add(), .notify_reactor_remove()
* methods
*
* The source api intends also to provide for simulation.
* There introduces two simulation-specific methods:
* .sim_current_tm()
* .sim_advance_until()
*
* A non-simulation source can implement these as calls to
* .online_current_tm(), .online_advance_until() respectively
* .online_current_tm() aborts since an online source is never exhausted
* .online_advance_until() is a no-op that returns 0
*
* Loop for consuming from a primary simulation source:
*
* brw<Source> s = ...;
* while(!s->is_exhausted())
* s->deliver_one();
*
* Secondary sources (sources that depend on other sources) can be
* in a state where they don't know their next event, in which case:
*
* s->is_notprimed() == true
*/
class ReactorSource : public AbstractSource {
public:
using utc_nanos = xo::time::utc_nanos;
/* abstract api for a source of events.
* Event representation is left open: Sources and Sinks
* need to have compatible event representations,
* and coordination is left to such (Source, Sink) pairs.
*
* Source->Sink activity may be expected to be mediated by a reactor,
* that implements the Reactor api.
*
* At any time, A Source can be associated with at most one reactor.
* Sources are informed of Reactor<->Source association being
* formed/broken by the
* .notify_reactor_add(), .notify_reactor_remove()
* methods
*
* The source api intends also to provide for simulation.
* There introduces two simulation-specific methods:
* .sim_current_tm()
* .sim_advance_until()
*
* A non-simulation source can implement these as calls to
* .online_current_tm(), .online_advance_until() respectively
* .online_current_tm() aborts since an online source is never exhausted
* .online_advance_until() is a no-op that returns 0
*
* Loop for consuming from a primary simulation source:
*
* brw<Source> s = ...;
* while(!s->is_exhausted())
* s->deliver_one();
*
* Secondary sources (sources that depend on other sources) can be
* in a state where they don't know their next event, in which case:
*
* s->is_notprimed() == true
*/
class ReactorSource : public AbstractSource {
public:
using utc_nanos = xo::time::utc_nanos;
public:
virtual ~ReactorSource() = default;
public:
virtual ~ReactorSource() = default;
/* true if source is currently empty (has 0 events to deliver) */
virtual bool is_empty() const = 0;
bool is_nonempty() const { return !this->is_empty(); }
/* true if source is currently empty (has 0 events to deliver) */
virtual bool is_empty() const = 0;
bool is_nonempty() const { return !this->is_empty(); }
/* true when source knows its next event
* A source that isn't primed is also excluded from simulation
* heap until it becomes primed.
* This make feasible simulation sources that
* depend on other simulation sources
*/
virtual bool is_primed() const { return !this->is_empty(); }
virtual bool is_notprimed() const { return this->is_empty(); }
/* true when source knows its next event
* A source that isn't primed is also excluded from simulation
* heap until it becomes primed.
* This make feasible simulation sources that
* depend on other simulation sources
*/
virtual bool is_primed() const { return !this->is_empty(); }
virtual bool is_notprimed() const { return this->is_empty(); }
/* if true, this source has no events, and will never publish more events
* - for sim, return true for a standalone source that has replayed all events
* - for rt, set during orderly
*/
virtual bool is_exhausted() const = 0;
/* if true, this source has no events, and will never publish more events
* - for sim, return true for a standalone source that has replayed all events
* - for rt, set during orderly
*/
virtual bool is_exhausted() const = 0;
/* if this is a simulation source and .is_exhausted is false:
* returns next event time; more precisely, no events exist prior to
* this time.
*
* if sim, and .is_primed = true,
* returns timestamp of next event
*/
virtual utc_nanos sim_current_tm() const = 0;
/* if this is a simulation source and .is_exhausted is false:
* returns next event time; more precisely, no events exist prior to
* this time.
*
* if sim, and .is_primed = true,
* returns timestamp of next event
*/
virtual utc_nanos sim_current_tm() const = 0;
/* promise:
* - .current_tm() > tm || .is_notprimed() || .is_exhausted() = true
* - if replay_flag is true, then any events between previous .current_tm()
* and new .current_tm() will have been published
*
* returns #of events delivered.
* does not count events that were skipped, so always returns 0 if
* replay_flag is false
*/
virtual std::uint64_t sim_advance_until(utc_nanos tm, bool replay_flag) = 0;
/* promise:
* - .current_tm() > tm || .is_notprimed() || .is_exhausted() = true
* - if replay_flag is true, then any events between previous .current_tm()
* and new .current_tm() will have been published
*
* returns #of events delivered.
* does not count events that were skipped, so always returns 0 if
* replay_flag is false
*/
virtual std::uint64_t sim_advance_until(utc_nanos tm, bool replay_flag) = 0;
/* informs source when it's added to a reactor
/* informs source when it's added to a reactor
* (see Reactor.add_source())
*/
virtual void notify_reactor_add(Reactor * /*reactor*/) {}
* (see Reactor.add_source())
*/
virtual void notify_reactor_add(Reactor * /*reactor*/) {}
/* informs source when it's removed from a reactor
* (see Reactor.remove_source())
*/
virtual void notify_reactor_remove(Reactor * /*reactor*/) {}
/* informs source when it's removed from a reactor
* (see Reactor.remove_source())
*/
virtual void notify_reactor_remove(Reactor * /*reactor*/) {}
// ----- Inherited from AbstractSource -----
// ----- Inherited from AbstractSource -----
/* deliver one event to attached sink
* interpretation of 'one event' is source-specific;
* could be a collapsed or batched event in practice.
*
* no-op if source is empty.
*
* if sim, promise:
* - new .current_tm >= old .current_tm() || .is_notprimed() || .is_exhausted()
*
* returns #of events delivered. Must be 0 or 1 in this context
*/
virtual std::uint64_t deliver_one() override = 0;
/* deliver one event to attached sink
* interpretation of 'one event' is source-specific;
* could be a collapsed or batched event in practice.
*
* no-op if source is empty.
*
* if sim, promise:
* - new .current_tm >= old .current_tm() || .is_notprimed() || .is_exhausted()
*
* returns #of events delivered. Must be 0 or 1 in this context
*/
virtual std::uint64_t deliver_one() override = 0;
protected:
/* default implementations for online sources */
utc_nanos online_current_tm() const;
uint64_t online_advance_until(utc_nanos tm, bool replay_flag);
}; /*ReactorSource*/
protected:
/* default implementations for online sources */
utc_nanos online_current_tm() const;
uint64_t online_advance_until(utc_nanos tm, bool replay_flag);
}; /*ReactorSource*/
using ReactorSourcePtr = ref::rp<ReactorSource>;
} /*namespace reactor*/
using ReactorSourcePtr = ref::rp<ReactorSource>;
} /*namespace reactor*/
} /*namespace xo*/
/* end ReactorSource.hpp */