Add bounded channels

tooling/pipeline/includes/BoundedChannel.tcc

@@ -0,0 +1,57 @@
+#include "BoundedChannel.h"
+
+template <typename T>
+void BoundedChannel<T>::Send(T item) {
+  // Acquire exclusive ownership of the mutex; released automatically on scope exit.
+  std::unique_lock lock(mutex_);
+
+  // Block until there is space in the queue or the channel has been closed.
+  // The predicate guards against spurious wakeups.
+  not_full_.wait(lock, [&] { return queue_.size() < capacity_ || closed_; });
+
+  // If the channel was closed while waiting, discard the item and return.
+  if (closed_) return;
+
+  // Move the item into the queue to avoid an unnecessary copy.
+  queue_.push(std::move(item));
+
+  // Wake one blocked Receive() call to signal that data is now available.
+  not_empty_.notify_one();
+}
+
+template <typename T>
+std::optional<T> BoundedChannel<T>::Receive() {
+  // Acquire exclusive ownership of the mutex.
+  std::unique_lock lock(mutex_);
+
+  // Block until the queue is non-empty or the channel has been closed.
+  // The predicate guards against spurious wakeups.
+  not_empty_.wait(lock, [&] { return !queue_.empty() || closed_; });
+
+  // If woken due to closure and no items remain, signal exhaustion via nullopt.
+  if (queue_.empty()) return std::nullopt;
+
+  // Move the front item out of the queue to avoid an unnecessary copy.
+  T item = std::move(queue_.front());
+  queue_.pop();
+
+  // Wake one blocked Send() call to signal that a slot has opened.
+  not_full_.notify_one();
+
+  return item;
+}
+
+template <typename T>
+void BoundedChannel<T>::close() {
+  // Acquire exclusive ownership of the mutex to ensure visibility of the flag.
+  std::unique_lock lock(mutex_);
+
+  // Mark the channel as closed; subsequent Send() calls will be dropped.
+  closed_ = true;
+
+  // Wake all blocked Send() callers so they can observe the closed flag and exit.
+  not_full_.notify_all();
+
+  // Wake all blocked Receive() callers so they can drain remaining items or return nullopt.
+  not_empty_.notify_all();
+}