1 files changed, 45 insertions, 0 deletions

diff --git a/port.h b/port.h
new file mode 100644
index 0000000..06a3aa5
--- /dev/null
+++ b/port.h
@@ -0,0 +1,45 @@
+#pragma once
+
+#include <cassert>
+#include <optional>
+#include <utility>
+
+#include "infra/sim.h"
+
+namespace infra {
+    template<typename T> struct port : public sim {
+        std::optional<T> consumer_side;
+        std::optional<T> producer_side;
+
+        bool can_read() { return consumer_side.has_value(); }
+        bool can_write() { return !producer_side.has_value(); }
+
+        T read() {
+            assert(can_read());
+            auto x = std::move(*consumer_side);
+            consumer_side.reset();
+            return x;
+        }
+
+        const T & peek() {
+            assert(can_read());
+            return *consumer_side;
+        }
+
+        void discard() {
+            consumer_side.reset();
+        }
+
+        void write(T &&x) {
+            assert(can_write());
+            producer_side = std::move(x);
+        }
+
+        void unclock() {
+            if (!consumer_side && producer_side) {
+                consumer_side = std::move(*producer_side);
+                producer_side.reset();
+            }
+        }
+    };
+}