first signal support

Author: frameworklabs

include/proto_activities.h

@@ -416,6 +416,12 @@ namespace proto_activities {
         bool did_suspend{};
     };
 
+    struct Updatable {
+        virtual ~Updatable() = default;
+        virtual void update() = 0;
+        Updatable* next{};
+    };
+
     struct Enter {
         Enter& operator=(const Enter& other) {
             thunk = nullptr;
@@ -426,12 +432,20 @@ namespace proto_activities {
             thunk();
             return *this;
         }
+        void add(Updatable* updatable) {
+            updatable->next = head;
+            head = updatable;
+        }
         void invoke() {
+            for (auto* updatable = head; updatable != nullptr; updatable = updatable->next) {
+                updatable->update();
+            }
             if (thunk) {
                 thunk();
             }
         }
         Thunk thunk;
+        Updatable* head{};
     };
 }
 
@@ -487,6 +501,39 @@ namespace proto_activities {
 
 #endif
 
+/* Signals */
+
+#ifdef __cplusplus
+namespace proto_activities {
+    struct BoolSignal final : Updatable {
+        BoolSignal(Enter& enter) {
+            enter.add(this);
+        }
+        BoolSignal(const BoolSignal&) = delete;
+        BoolSignal& operator=(const BoolSignal&) {
+            value_ = false;
+            return *this;
+        }
+        void emit() {
+            value_ = true;
+        }
+        operator bool() const {
+            return value_;
+        }
+        void update() final {
+            value_ = false;
+        }
+    private:
+        bool value_;
+    };
+}
+using pa_signal = proto_activities::BoolSignal;
+
+#define pa_def_signal(nm) pa_signal nm{_pa_enter};
+#define pa_emit(sig) sig.emit();
+
+#endif
+
 /* Trigger */
 
 #define pa_init(nm) _pa_reset(&_pa_inst_name(nm));

tests_cpp/tests.cpp

@@ -640,7 +640,7 @@ pa_activity (TestEvery, pa_ctx(pa_co_res(4); int value; int actual; int expected
     } pa_co_end;
 } pa_end;
 
-// Test Lifecycle
+// Lifecycle Tests
 
 namespace {
     bool did_defer = false;
@@ -802,6 +802,44 @@ pa_activity (TestLifecycle, pa_ctx(pa_co_res(2); pa_use(TestLifecycleBody); pa_u
     } pa_co_end
 } pa_end
 
+// Signal Tests
+
+pa_activity (TestSignalsBodySub, pa_ctx(), pa_signal& s1, pa_signal& s2) {
+    assert(!s1); assert(!s2);
+    pa_pause;
+
+    assert(!s1); assert(!s2);
+    pa_emit(s1); pa_emit(s2);
+    assert(s1); assert(s2);
+    pa_pause;
+
+    assert(!s1); assert(!s2);
+    pa_pause;
+} pa_end
+
+pa_activity (TestSignalsBody, pa_ctx(pa_enter_res; pa_use(TestSignalsBodySub);
+                                     pa_def_signal(s1); pa_def_signal(s2))) {
+    assert(!pa_self.s1); assert(!pa_self.s2);
+    pa_pause;
+
+    assert(!pa_self.s1); assert(!pa_self.s2);
+    pa_emit(pa_self.s1); pa_emit(pa_self.s2);
+    assert(pa_self.s1); assert(pa_self.s2);
+    pa_pause;
+
+    assert(!pa_self.s1); assert(!pa_self.s2);
+    pa_pause;
+
+    pa_run(TestSignalsBodySub, pa_self.s1, pa_self.s1);
+} pa_end
+
+pa_activity (TestSignals, pa_ctx_tm(pa_use(TestSignalsBody))) {
+    pa_run (TestSignalsBody);
+    pa_run (TestSignalsBody); // Test re-invocation
+    pa_after_abort (2, TestSignalsBody);
+    pa_run (TestSignalsBody); // Test re-invocation after abort
+} pa_end
+
 } // namespace tests
 
 // Test Driver
@@ -822,6 +860,7 @@ int main(int argc, char* argv[]) {
     run_test(tests, TestWhenReset);
     run_test(tests, TestEvery);
     run_test(tests, TestLifecycle);
+    run_test(tests, TestSignals);
 
     std::cout << "Done" << std::endl;