CancellerBinding.cpp

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// This include needs to be the very first to prevent problems with warnings
// regarding redefinition of _POSIX_C_SOURCE
#include "boost/python.hpp"

#include "IECorePython/CancellerBinding.h"
#include "IECorePython/ExceptionBinding.h"
#include "IECorePython/RefCountedBinding.h"

#include "IECore/Canceller.h"

#include <optional>

using namespace boost::python;
using namespace IECore;

namespace
{

double elapsedTimeWrapper( const Canceller &canceller )
{
	return std::chrono::duration<double>( canceller.elapsedTime() ).count();
}

class ScopedChildWrapper : public boost::noncopyable
{

	public :

		ScopedChildWrapper( Canceller &parent, Canceller &child )
			:	m_parent( &parent ), m_child( &child )
		{
		}

		void enter()
		{
			m_scope.emplace( m_parent.get(), m_child );
		}

		bool exit( boost::python::object excType, boost::python::object excValue, boost::python::object excTraceBack )
		{
			m_scope.reset();
			return false; // Don't suppress exceptions
		}

	private :

		CancellerPtr m_parent;
		CancellerPtr m_child;
		std::optional<Canceller::ScopedChild> m_scope;

};

} // namespace

namespace IECorePython
{

void bindCanceller()
{

	{
		scope s = RefCountedClass<Canceller, RefCounted>( "Canceller" )
			.def( init<>() )
			.def( "cancel", &Canceller::cancel )
			.def( "cancelled", &Canceller::cancelled )
			.def( "check", &Canceller::check )
			.staticmethod( "check" )
			.def( "elapsedTime", &elapsedTimeWrapper )
			.def( "addChild", &Canceller::addChild )
			.def( "removeChild", &Canceller::removeChild )
		;

		class_<ScopedChildWrapper, boost::noncopyable>( "ScopedChild", no_init )
			.def( init<Canceller &, Canceller &>() )
			.def( "__enter__", &ScopedChildWrapper::enter, return_self<>() )
			.def( "__exit__", &ScopedChildWrapper::exit )
		;
	}

	ExceptionClass<Cancelled>( "Cancelled", PyExc_RuntimeError )
		.def( init<>() )
	;

}

} // namespace IECorePython