RakNet/DependentExtensions/RPC3/RPC3_Boost.h

/*
 *  Copyright (c) 2014, Oculus VR, Inc.
 *  All rights reserved.
 *
 *  This source code is licensed under the BSD-style license found in the
 *  LICENSE file in the root directory of this source tree. An additional grant 
 *  of patent rights can be found in the PATENTS file in the same directory.
 *
 */

#ifndef __RPC3_BOOST_H
#define __RPC3_BOOST_H

// Fixes
// error C2504: 'boost::fusion::detail::invoke_impl<Function,Sequence,N,CBI,RandomAccess>' : base class undefined
// This defines the maximum number of parameters you can have
#ifndef BOOST_FUSION_INVOKE_MAX_ARITY
#define BOOST_FUSION_INVOKE_MAX_ARITY 10
#endif

// Boost dependencies
// Boost is assumed to be at C:\boost_1_43_0 based on the project settings
// If this is not where you downloaded boost, change the project settings Configuration Properties / C/C++ / General / Additional Include Directories
// If you don't have boost, get it from http://www.boost.org/users/download/
// If you don't want to use boost, use RPC4 instead which relies on assembly but has fewer features
#include "boost/type_traits.hpp"
#include "boost/function.hpp"
#include "boost/bind.hpp"
#include "boost/mpl/if.hpp"
#include "boost/mpl/apply.hpp"
#include "boost/function_types/parameter_types.hpp"
#include "boost/fusion/container/list/cons.hpp" // boost::fusion::nil
#include "boost/fusion/include/push_back.hpp"
#include "boost/fusion/include/invoke.hpp"
#include "boost/fusion/tuple/tuple.hpp"
#include "boost/fusion/tuple/make_tuple.hpp"
#include "boost/fusion/functional/invocation/invoke.hpp"
#include "boost/type_traits/is_array.hpp"

// Not needed?
//#include <boost/fusion/container/generation/make_vector.hpp>

#include "NetworkIDManager.h"
#include "NetworkIDObject.h"
#include "BitStream.h"

namespace RakNet
{
class RPC3;
class BitStream;


namespace _RPC3
{

enum InvokeResultCodes
{
	IRC_SUCCESS,
	IRC_NEED_BITSTREAM,
	IRC_NEED_NETWORK_ID_MANAGER,
	IRC_NEED_NETWORK_ID,
	IRC_NEED_CLASS_OBJECT,
};

struct InvokeArgs
{
	// Bitstream to use to deserialize
	RakNet::BitStream *bitStream;

	// NetworkIDManager to use to lookup objects
	NetworkIDManager *networkIDManager;

	// C++ class member object
	NetworkID classMemberObjectId;

	// The calling plugin
	RPC3 *caller;

	// The this pointer for C++
	NetworkIDObject *thisPtr;
};

typedef boost::fusion::tuple<bool, boost::function<InvokeResultCodes (InvokeArgs)> > FunctionPointer;

struct StrWithDestructor
{
	char *c;
	~StrWithDestructor() {if (c) delete c;}
};

enum RPC3TagFlag
{
	RPC3_TAG_FLAG_DEREF=1,
	RPC3_TAG_FLAG_ARRAY=2,
};

struct RPC3Tag
{
	RPC3Tag() {}
	RPC3Tag(void *_v, unsigned int _count, RPC3TagFlag _flag) : v(_v), count(_count), flag((unsigned char)_flag) {}
	void* v;
	unsigned int count;
	unsigned char flag;
};

// Track the pointers tagged with RakNet::_RPC3::Deref
static RPC3Tag __RPC3TagPtrs[BOOST_FUSION_INVOKE_MAX_ARITY+1];
static int __RPC3TagHead=0;
static int __RPC3TagTail=0;

// If this assert hits, then RakNet::_RPC3::Deref was called more times than the argument was passed to the function
static void __RPC3_Tag_AddHead(const RPC3Tag &p)
{
	// Update tag if already in array
	int i;
	for (i=__RPC3TagTail; i!=__RPC3TagHead; i=(i+1)%BOOST_FUSION_INVOKE_MAX_ARITY)
	{
		if (__RPC3TagPtrs[i].v==p.v)
		{
			if (p.flag==RPC3_TAG_FLAG_ARRAY)
			{
				__RPC3TagPtrs[i].count=p.count;
			}
			__RPC3TagPtrs[i].flag|=p.flag;

			return;
		}
	}

	__RPC3TagPtrs[__RPC3TagHead]=p;
	__RPC3TagHead = (__RPC3TagHead + 1) % BOOST_FUSION_INVOKE_MAX_ARITY;
	assert(__RPC3TagHead!=__RPC3TagTail);
}
static void __RPC3ClearTail(void) {
	while (__RPC3TagTail!=__RPC3TagHead)
	{
		if (__RPC3TagPtrs[__RPC3TagTail].v==0)
			__RPC3TagTail = (__RPC3TagTail+1) % BOOST_FUSION_INVOKE_MAX_ARITY;
		else
			return;
	}
}
static bool __RPC3ClearPtr(void* p, RPC3Tag *tag) {
	int i;
	for (i=__RPC3TagTail; i!=__RPC3TagHead; i=(i+1)%BOOST_FUSION_INVOKE_MAX_ARITY)
	{
		if (__RPC3TagPtrs[i].v==p)
		{
			*tag=__RPC3TagPtrs[i];
			__RPC3TagPtrs[i].v=0;
			__RPC3ClearTail();			
			return true;
		}
	}
	tag->flag=0;
	tag->count=1;
	return false;
}

template <class templateType>
inline const templateType& Deref(const templateType & t) {
	__RPC3_Tag_AddHead(RPC3Tag((void*)t,1,RPC3_TAG_FLAG_DEREF));
	return t;
}

template <class templateType>
inline const templateType& PtrToArray(unsigned int count, const templateType & t) {
	__RPC3_Tag_AddHead(RPC3Tag((void*)t,count,RPC3_TAG_FLAG_ARRAY));
	return t;
}

struct ReadBitstream
{
	static void applyArray(RakNet::BitStream &bitStream, RakNet::BitStream* t){apply(bitStream,t);}

	static void apply(RakNet::BitStream &bitStream, RakNet::BitStream* t)
	{
		BitSize_t numBitsUsed;
		bitStream.ReadCompressed(numBitsUsed);
		bitStream.Read(t,numBitsUsed);
	}
};

//template <typename T>
struct ReadPtr
{
	template <typename T2>
	static inline void applyArray(RakNet::BitStream &bitStream, T2 *t) {bitStream >> (*t);}
	template <typename T2>
	static inline void apply(RakNet::BitStream &bitStream, T2 *t) {bitStream >> (*t);}

	static inline void apply(RakNet::BitStream &bitStream, char *&t) {applyStr(bitStream, (char *&) t);}
	static inline void apply(RakNet::BitStream &bitStream, unsigned char *&t) {applyStr(bitStream, (char *&) t);}
	static inline void apply(RakNet::BitStream &bitStream, const char *&t) {applyStr(bitStream, (char *&) t);}
	static inline void apply(RakNet::BitStream &bitStream, const unsigned char *&t) {applyStr(bitStream, (char *&) t);}
	static inline void applyStr(RakNet::BitStream &bitStream, char *&t)
	{
		RakNet::RakString rs;
		bitStream >> rs;
		size_t len = rs.GetLength()+1;
		
		// The caller should have already allocated memory, so we need to free
		// it and allocate a new buffer.
		RakAssert("Expected allocated array, got NULL" && (NULL != t));
		delete [] t;

		t = new char [len];
		memcpy(t,rs.C_String(),len);
	}
};


template< typename T >
struct DoRead
{
	typedef typename boost::mpl::if_<
		boost::is_convertible<T*,RakNet::BitStream*>,
		ReadBitstream,
		ReadPtr >::type type;
};


template< typename T >
struct ReadWithoutNetworkIDNoPtr
{
	static InvokeResultCodes apply(InvokeArgs &args, T &t)
	{
//		printf("ReadWithoutNetworkIDNoPtr\n");

		DoRead< typename boost::remove_pointer<T>::type >::type::apply(* (args.bitStream),&t);

		return IRC_SUCCESS;
	}

	// typedef boost::mpl::false_ Cleanup;
	template< typename T2 >
	static void Cleanup(T2 &t) {}
};

template< typename T >
struct ReadWithNetworkIDPtr
{
	static InvokeResultCodes apply(InvokeArgs &args, T &t)
	{
//		printf("ReadWithNetworkIDPtr\n");
		// Read the network ID

		bool isNull;
		args.bitStream->Read(isNull);
		if (isNull)
		{
			t=0;
			return IRC_SUCCESS;
		}

		bool deref, isArray;
		args.bitStream->Read(deref);
		args.bitStream->Read(isArray);
		unsigned int count;
		if (isArray)
			args.bitStream->ReadCompressed(count);
		else
			count=1;
		NetworkID networkId;
		for (unsigned int i=0; i < count; i++)
		{
			args.bitStream->Read(networkId);
			t = args.networkIDManager->GET_OBJECT_FROM_ID< T >(networkId);
			if (deref)
			{
				BitSize_t bitsUsed;
				args.bitStream->AlignReadToByteBoundary();
				args.bitStream->Read(bitsUsed);

				if (t)
				{
					DoRead< typename boost::remove_pointer<T>::type >::type::apply(* (args.bitStream),t);
				}
				else
				{
					// Skip data!
					args.bitStream->IgnoreBits(bitsUsed);
				}
			}
		}
		
		return IRC_SUCCESS;
	}

	template< typename T2 >
	static void Cleanup(T2 &t) {}
};

template< typename T >
struct ReadWithoutNetworkIDPtr
{
	template <typename T2>
	static InvokeResultCodes apply(InvokeArgs &args, T2 &t)
	{
//		printf("ReadWithoutNetworkIDPtr\n");
		
		bool isNull=false;
		args.bitStream->Read(isNull);
		if (isNull)
		{
			t=0;
			return IRC_SUCCESS;
		}

		typedef typename boost::remove_pointer< T >::type ActualObjectType;

		bool isArray=false;
		unsigned int count;
		args.bitStream->Read(isArray);
		if (isArray)
			args.bitStream->ReadCompressed(count);
		else
			count=1;

		t = new ActualObjectType[count]();
		if (isArray)
		{
			for (unsigned int i=0; i < count; i++)
			{
				DoRead< typename boost::remove_pointer<T>::type >::type::applyArray(* (args.bitStream),t+i);
			}
		}
		else
		{
			DoRead< typename boost::remove_pointer<T>::type >::type::apply(* (args.bitStream),t);
		}

		return IRC_SUCCESS;
	}

	template< typename T2 >
	static void Cleanup(T2 &t) {
		if (t)
			delete [] t;
	}
};

template< typename T >
struct SetRPC3Ptr
{
	static InvokeResultCodes apply(InvokeArgs &args, T &obj)
	{
		obj=args.caller;
		return IRC_SUCCESS;
	}

	//typedef boost::mpl::false_ Cleanup;
	template< typename T2 >
	static void Cleanup(T2 &t) {}
};

/*
template< typename T >
struct ReadWithNetworkID
{
	typedef typename boost::mpl::if_<
		boost::is_pointer<T>
		, typename ReadWithNetworkIDPtr<T> // true
		, typename ReadWithNetworkIDNoPtr<T>
	>::type type;
};
*/

template< typename T >
struct ReadWithoutNetworkID
{
	typedef typename boost::mpl::if_<
		boost::is_pointer<T>
		, ReadWithoutNetworkIDPtr<T> // true
		, ReadWithoutNetworkIDNoPtr<T>
	>::type type;
};

template< typename T >
struct identity 
{
	typedef T type;
};

template< typename T >
struct IsRPC3Ptr
{
	typedef typename boost::mpl::if_<
		boost::is_convertible<T,RPC3*>,
		boost::mpl::true_,
		boost::mpl::false_>::type type;
};

template< typename T >
struct ShouldReadNetworkID
{
	/*
	typedef typename boost::mpl::if_<
		boost::is_pointer<T>,
		typename identity<T>::type,
		boost::add_pointer<T>>::type typeWithPtr;

	typedef typename boost::mpl::if_<
		boost::is_convertible<typeWithPtr,NetworkIDObject*>,
		boost::mpl::true_,
		boost::mpl::false_>::type type;
		*/

	typedef typename boost::mpl::if_<
		boost::is_convertible<T,NetworkIDObject*>,
		boost::mpl::true_,
		boost::mpl::false_>::type type;
};

template< typename T >
struct GetReadFunction
{
	/*
	typedef typename boost::mpl::if_<
		typename ShouldReadNetworkID<T>::type
		, typename ReadWithNetworkID<T>::type
		, typename ReadWithoutNetworkID<T>::type
	>::type type;
	*/

	typedef typename boost::mpl::if_<
		typename ShouldReadNetworkID<T>::type
		, ReadWithNetworkIDPtr<T>
		, typename ReadWithoutNetworkID<T>::type
	>::type type;
};

template< typename T >
struct ProcessArgType
{
	typedef typename boost::mpl::if_<
		typename IsRPC3Ptr<T>::type
		, SetRPC3Ptr<T>
		, typename GetReadFunction<T>::type
	>::type type;
};

template< typename Function
	, class From = typename boost::mpl::begin< boost::function_types::parameter_types<Function> >::type
	, class To   = typename boost::mpl::end< boost::function_types::parameter_types<Function> >::type
>
struct BoostRPCInvoker
{
	// add an argument to a Fusion cons-list for each parameter type
	template<typename Args>
	static inline
		InvokeResultCodes apply(Function func, InvokeArgs &functionArgs, Args const &args)
	{
		typedef typename boost::mpl::deref<From>::type arg_type;
		typedef typename boost::mpl::next<From>::type next_iter_type;
		typedef typename boost::remove_reference<arg_type>::type arg_type_no_ref;

		arg_type_no_ref argType;
		ProcessArgType< arg_type_no_ref >::type::apply(functionArgs, argType);

		InvokeResultCodes irc = BoostRPCInvoker<Function, next_iter_type, To>::apply
			( func, functionArgs, boost::fusion::push_back(args, boost::ref(argType) ) );

		ProcessArgType< arg_type_no_ref >::type::Cleanup(argType);
		return irc;
	}
};

template< typename Function
, class From = typename boost::mpl::begin< boost::function_types::parameter_types<Function> >::type
, class To   = typename boost::mpl::end< boost::function_types::parameter_types<Function> >::type
>
struct BoostRPCInvoker_ThisPtr
{
	// add an argument to a Fusion cons-list for each parameter type
	template<typename Args>
	static inline
		InvokeResultCodes apply(Function func, InvokeArgs &functionArgs, Args const &args)
	{
		typedef typename boost::mpl::deref<From>::type arg_type;
		typedef typename boost::mpl::next<From>::type next_iter_type;

		arg_type argType = (arg_type) *(functionArgs.thisPtr);

		return BoostRPCInvoker<Function, next_iter_type, To>::apply
			( func, functionArgs, boost::fusion::push_back(args, boost::ref(argType) ) );
	}
};

template<typename Function, class To>
struct BoostRPCInvoker<Function,To,To>
{
	// the argument list is complete, now call the function
	template<typename Args>
	static inline
		InvokeResultCodes apply(Function func, InvokeArgs&, Args const &args)
	{
		boost::fusion::invoke(func,args);

		return IRC_SUCCESS;
	}
};

template <typename T>
struct DoNothing
{
	static void apply(RakNet::BitStream &bitStream, T& t)
	{
		(void) bitStream;
		(void) t;
//		printf("DoNothing\n");
	}
};

struct WriteBitstream
{
	static void applyArray(RakNet::BitStream &bitStream, RakNet::BitStream* t) {apply(bitStream,t);}
	static void apply(RakNet::BitStream &bitStream, RakNet::BitStream* t)
	{
		BitSize_t oldReadOffset = t->GetReadOffset();
		t->ResetReadPointer();
		bitStream.WriteCompressed(t->GetNumberOfBitsUsed());
		bitStream.Write(t);
		t->SetReadOffset(oldReadOffset);
	}
};

//template <typename T>
struct WritePtr
{
	template <typename T2>
	static inline void applyArray(RakNet::BitStream &bitStream, T2 *t) {bitStream << (*t);}
	template <typename T2>
	static inline void apply(RakNet::BitStream &bitStream, T2 *t) {bitStream << (*t);}
//	template <>
	static inline void apply(RakNet::BitStream &bitStream, char *t) {bitStream << t;}
//	template <>
	static inline void apply(RakNet::BitStream &bitStream, unsigned char *t) {bitStream << t;}
//	template <>
	static inline void apply(RakNet::BitStream &bitStream, const char *t) {bitStream << t;}
//	template <>
	static inline void apply(RakNet::BitStream &bitStream, const unsigned char *t) {bitStream << t;}
};

template< typename T >
struct DoWrite
{
	typedef typename boost::mpl::if_<
		boost::is_convertible<T*,RakNet::BitStream*>,
		WriteBitstream,
		WritePtr >::type type;
};

template <typename T>
struct WriteWithNetworkIDPtr
{
	static void apply(RakNet::BitStream &bitStream, T& t)
	{
		bool isNull;
		isNull=(t==0);
		bitStream.Write(isNull);
		if (isNull)
			return;
		RPC3Tag tag;
		__RPC3ClearPtr(t, &tag);
		bool deref = (tag.flag & RPC3_TAG_FLAG_DEREF) !=0;
		bool isArray = (tag.flag & RPC3_TAG_FLAG_ARRAY) !=0;
		bitStream.Write(deref);
		bitStream.Write(isArray);
		if (isArray)
		{
			bitStream.WriteCompressed(tag.count);
		}
		for (unsigned int i=0; i < tag.count; i++)
		{
			NetworkID inNetworkID=t->GetNetworkID();
			bitStream << inNetworkID;
			if (deref)
			{
				// skip bytes, write data, go back, write number of bits written, reset cursor
				bitStream.AlignWriteToByteBoundary();
				BitSize_t writeOffset1 = bitStream.GetWriteOffset();
				BitSize_t bitsUsed1=bitStream.GetNumberOfBitsUsed();
				bitStream.Write(bitsUsed1);
				bitsUsed1=bitStream.GetNumberOfBitsUsed();
				DoWrite< typename boost::remove_pointer<T>::type >::type::apply(bitStream,t);
				BitSize_t writeOffset2 = bitStream.GetWriteOffset();
				BitSize_t bitsUsed2=bitStream.GetNumberOfBitsUsed();
				bitStream.SetWriteOffset(writeOffset1);
				bitStream.Write(bitsUsed2-bitsUsed1);
				bitStream.SetWriteOffset(writeOffset2);
			}
		}		
	}
};

template <typename T>
struct WriteWithoutNetworkIDNoPtr
{
	static void apply(RakNet::BitStream &bitStream, T& t)
	{
		DoWrite< typename boost::remove_pointer<T>::type >::type::apply(bitStream,&t);
	}
};

template <typename T>
struct WriteWithoutNetworkIDPtr
{
	static void apply(RakNet::BitStream &bitStream, T& t)
	{
		bool isNull;
		isNull=(t==0);
		bitStream.Write(isNull);
		if (isNull)
			return;

		RPC3Tag tag;
		__RPC3ClearPtr((void*) t, &tag);
		bool isArray = (tag.flag & RPC3_TAG_FLAG_ARRAY) !=0;
		bitStream.Write(isArray);
		if (isArray)
		{
			bitStream.WriteCompressed(tag.count);
		}
		if (isArray)
		{
			for (unsigned int i=0; i < tag.count; i++)
				DoWrite< typename boost::remove_pointer<T>::type >::type::applyArray(bitStream,t+i);
		}
		else
		{
			DoWrite< typename boost::remove_pointer<T>::type >::type::apply(bitStream,t);
		}
		
	}
};

template <typename T>
struct SerializeCallParameterBranch
{
	typedef typename boost::mpl::if_<
		typename IsRPC3Ptr<T>::type
		, DoNothing<T>
		, WriteWithoutNetworkIDPtr<T>
	>::type typeCheck1;

	typedef typename boost::mpl::if_<
		boost::is_pointer<T>
		, typeCheck1
		, WriteWithoutNetworkIDNoPtr<T>
	>::type typeCheck2;

	typedef typename boost::mpl::if_<
		typename ShouldReadNetworkID<T>::type
		, WriteWithNetworkIDPtr<T>
		, typeCheck2
	>::type type;
};
template<typename Function>
struct GetBoundPointer_C
{
//	typedef typename GetBoundPointer_C type;
	static FunctionPointer GetBoundPointer(Function f)
	{
		return FunctionPointer(false, boost::bind( & BoostRPCInvoker<Function>::template apply<boost::fusion::nil>, f, _1, boost::fusion::nil() ));
	}
};

template<typename Function>
struct GetBoundPointer_CPP
{
//	typedef typename GetBoundPointer_CPP type;
	static FunctionPointer GetBoundPointer(Function f)
	{
		return FunctionPointer(true, boost::bind( & BoostRPCInvoker_ThisPtr<Function>::template apply<boost::fusion::nil>, f, _1, boost::fusion::nil() ));
	}
};
template<typename Function>
FunctionPointer GetBoundPointer(Function f)
{
	return boost::mpl::if_<
	boost::is_member_function_pointer<Function>
	, GetBoundPointer_CPP<Function>
	, GetBoundPointer_C<Function>
	>::type::GetBoundPointer(f);
	
//	return FunctionPointer(true, boost::bind( & BoostRPCInvoker<Function>::template apply<boost::fusion::nil>, f, _1, boost::fusion::nil() ) );
}


}
}

#endif