Files
secs-gem/include/secsgem/gem/e84_asio_timers.hpp
raphael 54dcf6c532 e84: asio adapter for handshake timers + wall-clock test
The E84StateMachine timers landed last commit but stayed theoretical —
arming was delivered via abstract callbacks the application had to
glue to a real clock.  This commit ships the canonical glue:

- include/secsgem/gem/e84_asio_timers.hpp: header-only
  E84AsioTimers wraps three asio::steady_timers, wires set_timer_handlers
  on attach(), routes async_wait expiry back into fsm.on_timeout().
  detach() cancels everything cleanly.

- tests/test_e84_asio_timers.cpp: four scenarios exercised through a
  real asio::io_context with wall-clock timers — TA1 expiry,
  signal-driven cancel before TA1 fires, TA3 expiry from the
  Transferring state, and detach() halting further transitions.
  These cover the integration the synthetic unit tests in
  test_e84_timers.cpp can't reach.

- INTEGRATION.md §4.6: the vendor-side recipe — create the port,
  set timeouts, make_shared<E84AsioTimers>(...)::attach(), feed signals
  from your I/O bridge.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-06-09 14:08:16 +02:00

85 lines
2.8 KiB
C++

#pragma once
#include <asio.hpp>
#include <array>
#include <chrono>
#include <memory>
#include <utility>
#include "secsgem/gem/e84_state.hpp"
// asio-backed driver for the SEMI E84 §6 handshake timers (TA1/TA2/TA3).
//
// `E84StateMachine` is I/O-free by design: it tells the application to
// arm or cancel a timer via callbacks and expects the application to
// drive a real clock and call `on_timeout(id)` on expiry. This
// header-only adapter is the canonical asio glue — three steady_timers,
// wired so that an arm() restarts the matching timer and a cancel()
// stops it; expiry routes back into `fsm.on_timeout(id)`.
//
// Usage (one adapter per E84StateMachine, one E84StateMachine per
// load port via `E84PortStore::get(port_id)`):
//
// E84StateMachine* fsm = model->e84_ports.get(port_id);
// auto driver = std::make_shared<E84AsioTimers>(io.get_executor(), *fsm);
// driver->attach(); // wires set_timer_handlers
// fsm->set_timeouts({2s, 2s, 60s}); // SEMI defaults
//
// Keep the shared_ptr alive for as long as the FSM may transition —
// typically tied to the load-port lifetime. Detach (or just drop the
// shared_ptr) before destroying the FSM.
namespace secsgem::gem {
class E84AsioTimers : public std::enable_shared_from_this<E84AsioTimers> {
public:
E84AsioTimers(asio::any_io_executor ex, E84StateMachine& fsm)
: fsm_(fsm),
timers_{{asio::steady_timer{ex}, asio::steady_timer{ex},
asio::steady_timer{ex}}} {}
E84AsioTimers(const E84AsioTimers&) = delete;
E84AsioTimers& operator=(const E84AsioTimers&) = delete;
// Wires the FSM's arm/cancel callbacks to the internal timers. Must
// be called after construction (we need shared_from_this for the
// expiry continuation).
void attach() {
auto self = shared_from_this();
fsm_.set_timer_handlers(
[self](E84TimerId id, std::chrono::milliseconds d) {
self->arm_(id, d);
},
[self](E84TimerId id) { self->cancel_(id); });
}
// Detach so timers stop driving the FSM. Pending expiries are
// cancelled; in-flight asio handlers see ec == operation_aborted and
// return early.
void detach() {
for (auto& t : timers_) t.cancel();
fsm_.set_timer_handlers({}, {});
}
private:
void arm_(E84TimerId id, std::chrono::milliseconds d) {
auto& t = timer_for_(id);
t.expires_after(d);
auto self = shared_from_this();
t.async_wait([self, id](std::error_code ec) {
if (ec) return; // cancelled or timer destroyed
self->fsm_.on_timeout(id);
});
}
void cancel_(E84TimerId id) { timer_for_(id).cancel(); }
asio::steady_timer& timer_for_(E84TimerId id) {
return timers_[static_cast<std::size_t>(id) - 1];
}
E84StateMachine& fsm_;
std::array<asio::steady_timer, 3> timers_;
};
} // namespace secsgem::gem