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lib/cancellation_registration.cpp

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+///////////////////////////////////////////////////////////////////////////////
+// Copyright (c) Lewis Baker
+// Licenced under MIT license. See LICENSE.txt for details.
+///////////////////////////////////////////////////////////////////////////////
+
+#include <cppcoro/cancellation_registration.hpp>
+
+#include "cancellation_state.hpp"
+
+#include <cassert>
+
+cppcoro::cancellation_registration::~cancellation_registration()
+{
+	if (m_state != nullptr)
+	{
+		m_state->deregister_callback(this);
+		m_state->release_token_ref();
+	}
+}
+
+void cppcoro::cancellation_registration::register_callback(cancellation_token&& token)
+{
+	auto* state = token.m_state;
+	if (state != nullptr && state->can_be_cancelled())
+	{
+		m_state = state;
+		if (state->try_register_callback(this))
+		{
+			token.m_state = nullptr;
+		}
+		else
+		{
+			m_state = nullptr;
+			m_callback();
+		}
+	}
+	else
+	{
+		m_state = nullptr;
+	}
+}