NMTCreator.h

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/* Copyright (C) 2020 Wildfire Games.
 * This file is part of 0 A.D.
 *
 * 0 A.D. is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 *
 * 0 A.D. is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with 0 A.D.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "Serialization.h"
#include <vector>

// If included from within the NMT Creation process, perform a pass
#ifdef CREATING_NMT

#include NMT_CREATE_HEADER_NAME

#undef START_NMTS
#undef END_NMTS
#undef START_NMT_CLASS
#undef START_NMT_CLASS_DERIVED
#undef NMT_FIELD_INT
#undef NMT_FIELD
#undef NMT_FIELD_SECRET
#undef NMT_START_ARRAY
#undef NMT_END_ARRAY
#undef END_NMT_CLASS

#else
// If not within the creation process, and called with argument, perform the
// creation process with the header specified
#ifdef NMT_CREATE_HEADER_NAME

#ifndef ARRAY_STRUCT_PREFIX
#define ARRAY_STRUCT_PREFIX(_nm) S_##_nm
#endif

#define CREATING_NMT

#ifndef NMT_CREATOR_IMPLEMENT

/*************************************************************************/
// Pass 1, class definition
#define NMT_CREATOR_PASS_CLASSDEF
#define START_NMTS()
#define END_NMTS()

#define START_NMT_CLASS(_nm, _tp) \
    START_NMT_CLASS_DERIVED(CNetMessage, _nm, _tp)

/**
 * Start the definition of a network message type.
 *
 * @param _base The name of the base class of the message
 * @param _nm The name of the class
 * @param _tp The NetMessageType associated with the class. It is *not* safe to
 * have several classes with the same value of _tp in the same executable
 */
#define START_NMT_CLASS_DERIVED(_base, _nm, _tp) \
CNetMessage *Deserialize##_nm(const u8 *, size_t); \
class _nm: public _base \
{ \
protected: \
    _nm(NetMessageType type): _base(type) {}\
    \
    /* This one is for subclasses that want to use the base class' string */ \
    /* converters to get SubMessage { <parent fields>, ... } */ \
    CStr ToStringRaw() const;\
public: \
    _nm(): _base(_tp) {} \
    virtual size_t GetSerializedLength() const; \
    virtual u8 *Serialize(u8 *buffer) const; \
    virtual const u8 *Deserialize(const u8 *pos, const u8 *end); \
    virtual CStr ToString() const; \
    inline operator CStr () const \
    { return ToString(); }

/**
 * Add an integer field to the message type.
 *
 * @param _nm The name of the field
 * @param _hosttp The local type of the field (the data type used in the field
 * definition)
 * @param _netsz The number of bytes that should be serialized. If the variable
 * has a value larger than the maximum value of the specified network size,
 * higher order bytes will be discarded.
 */
#define NMT_FIELD_INT(_nm, _hosttp, _netsz) \
    _hosttp _nm;

/**
 * Add a generic field to the message type. The data type must be a class
 * implementing the ISerializable interface
 *
 * @param _tp The local data type of the field
 * @param _nm The name of the field
 * @see ISerializable
 */
#define NMT_FIELD(_tp, _nm) \
    _tp _nm;

/**
 * Likewise, but the string representation is hidden.
 * NB: the data length is not hidden, so make sure to use fixed-length data if confidentiality is desirable.
 */
#define NMT_FIELD_SECRET(_tp, _nm) \
    _tp _nm;

#define NMT_START_ARRAY(_nm) \
    struct ARRAY_STRUCT_PREFIX(_nm); \
    std::vector <ARRAY_STRUCT_PREFIX(_nm)> _nm; \
    struct ARRAY_STRUCT_PREFIX(_nm) {

#define NMT_END_ARRAY() \
    };

#define END_NMT_CLASS() };

#include "NMTCreator.h"
#undef NMT_CREATOR_PASS_CLASSDEF

#else // NMT_CREATOR_IMPLEMENT

#include "StringConverters.h"

/*************************************************************************/
// Pass 2, GetSerializedLength
#define NMT_CREATOR_PASS_GETLENGTH
#define START_NMTS()
#define END_NMTS()

#define START_NMT_CLASS(_nm, _tp) \
    START_NMT_CLASS_DERIVED(CNetMessage, _nm, _tp)
#define START_NMT_CLASS_DERIVED(_base, _nm, _tp) \
size_t _nm::GetSerializedLength() const \
{ \
    size_t ret=_base::GetSerializedLength(); \
    const _nm *thiz=this;\
    UNUSED2(thiz);  // preempt any "unused" warning

#define NMT_START_ARRAY(_nm) \
    std::vector <ARRAY_STRUCT_PREFIX(_nm)>::const_iterator it=_nm.begin(); \
    while (it != _nm.end()) \
    { \
        const ARRAY_STRUCT_PREFIX(_nm) *thiz=&*it;\
        UNUSED2(thiz);  // preempt any "unused" warning

#define NMT_END_ARRAY() \
        ++it; \
    }

#define NMT_FIELD_INT(_nm, _hosttp, _netsz) \
    ret += _netsz;

#define NMT_FIELD(_tp, _nm) \
    ret += thiz->_nm.GetSerializedLength();

#define NMT_FIELD_SECRET(_tp, _nm) \
    ret += thiz->_nm.GetSerializedLength();

#define END_NMT_CLASS() \
    return ret; \
};

#include "NMTCreator.h"
#undef NMT_CREATOR_PASS_GETLENGTH

/*************************************************************************/
// Pass 3, Serialize

#define NMT_CREATOR_PASS_SERIALIZE

#define START_NMTS()
#define END_NMTS()

#define START_NMT_CLASS(_nm, _tp) \
    START_NMT_CLASS_DERIVED(CNetMessage, _nm, _tp)
#define START_NMT_CLASS_DERIVED(_base, _nm, _tp) \
u8 *_nm::Serialize(u8 *buffer) const \
{ \
    /*printf("In " #_nm "::Serialize()\n");*/ \
    u8 *pos=_base::Serialize(buffer); \
    const _nm *thiz=this;\
    UNUSED2(thiz);  // preempt any "unused" warning

#define NMT_START_ARRAY(_nm) \
    std::vector <ARRAY_STRUCT_PREFIX(_nm)>::const_iterator it=_nm.begin(); \
    while (it != _nm.end()) \
    { \
        const ARRAY_STRUCT_PREFIX(_nm) *thiz=&*it;\
        UNUSED2(thiz);  // preempt any "unused" warning

#define NMT_END_ARRAY() \
        ++it; \
    }

#define NMT_FIELD_INT(_nm, _hosttp, _netsz) \
    Serialize_int_##_netsz(pos, thiz->_nm); \

#define NMT_FIELD(_tp, _nm) \
    pos=thiz->_nm.Serialize(pos);

#define NMT_FIELD_SECRET(_tp, _nm) \
    pos=thiz->_nm.Serialize(pos);

#define END_NMT_CLASS() \
    return pos; \
}

#include "NMTCreator.h"

#undef NMT_CREATOR_PASS_SERIALIZE

/*************************************************************************/
// Pass 4, Deserialize

#define NMT_CREATOR_PASS_DESERIALIZE

#define START_NMTS()
#define END_NMTS()

#define BAIL_DESERIALIZER return NULL

#define START_NMT_CLASS(_nm, _tp) \
    START_NMT_CLASS_DERIVED(CNetMessage, _nm, _tp)
#define START_NMT_CLASS_DERIVED(_base, _nm, _tp) \
const u8 *_nm::Deserialize(const u8 *pos, const u8 *end) \
{ \
    pos=_base::Deserialize(pos, end); \
    if (pos == NULL) BAIL_DESERIALIZER;\
    _nm *thiz=this; \
    /*printf("In Deserialize" #_nm "\n"); */\
    UNUSED2(thiz);  // preempt any "unused" warning


#define NMT_START_ARRAY(_nm) \
    while (pos < end) \
    { \
        ARRAY_STRUCT_PREFIX(_nm) *thiz=&*_nm.insert(_nm.end(), ARRAY_STRUCT_PREFIX(_nm)());\
        UNUSED2(thiz);  // preempt any "unused" warning

#define NMT_END_ARRAY() \
    }

#define NMT_FIELD_INT(_nm, _hosttp, _netsz) \
    if (pos+_netsz > end) BAIL_DESERIALIZER; \
    Deserialize_int_##_netsz(pos, thiz->_nm); \
    /*printf("\t" #_nm " == 0x%x\n", thiz->_nm);*/

#define NMT_FIELD(_tp, _nm) \
    if ((pos=thiz->_nm.Deserialize(pos, end)) == NULL) BAIL_DESERIALIZER;

#define NMT_FIELD_SECRET(_tp, _nm) \
    if ((pos=thiz->_nm.Deserialize(pos, end)) == NULL) BAIL_DESERIALIZER;

#define END_NMT_CLASS() \
    return pos; \
}

#include "NMTCreator.h"

#undef BAIL_DESERIALIZER

#undef NMT_CREATOR_PASS_DESERIALIZE

/*************************************************************************/
// Pass 5, String Representation

#define START_NMTS()
#define END_NMTS()

#define START_NMT_CLASS(_nm, _tp) \
CStr _nm::ToString() const \
{ \
    CStr ret=#_nm " { "; \
    return ret + ToStringRaw() + " }"; \
} \
CStr _nm::ToStringRaw() const \
{ \
    CStr ret; \
    const _nm *thiz=this;\
    UNUSED2(thiz);  // preempt any "unused" warning

#define START_NMT_CLASS_DERIVED(_base, _nm, _tp) \
CStr _nm::ToString() const \
{ \
    CStr ret=#_nm " { "; \
    return ret + ToStringRaw() + " }"; \
} \
CStr _nm::ToStringRaw() const \
{ \
    CStr ret=_base::ToStringRaw() + ", "; \
    const _nm *thiz=this;\
    UNUSED2(thiz);  // preempt any "unused" warning

#define NMT_START_ARRAY(_nm) \
    ret+=#_nm ": { "; \
    std::vector < ARRAY_STRUCT_PREFIX(_nm) >::const_iterator it=_nm.begin(); \
    while (it != _nm.end()) \
    { \
        ret+=" { "; \
        const ARRAY_STRUCT_PREFIX(_nm) *thiz=&*it;\
        UNUSED2(thiz);  // preempt any "unused" warning

#define NMT_END_ARRAY() \
        ++it; \
        ret=ret.substr(0, ret.length()-2)+" }, "; \
    } \
    ret=ret.substr(0, ret.length()-2)+" }, ";

#define NMT_FIELD_INT(_nm, _hosttp, _netsz) \
    ret += #_nm ": "; \
    ret += NetMessageStringConvert(thiz->_nm); \
    ret += ", ";

#define NMT_FIELD(_tp, _nm) \
    ret += #_nm ": "; \
    ret += NetMessageStringConvert(thiz->_nm); \
    ret += ", ";

#define NMT_FIELD_SECRET(_tp, _nm) \
    ret += #_nm ": [secret], ";

#define END_NMT_CLASS() \
    return ret.substr(0, ret.length()-2); \
}

#include "NMTCreator.h"

#endif // #ifdef NMT_CREATOR_IMPLEMENT

/*************************************************************************/
// Cleanup
#undef NMT_CREATE_HEADER_NAME
#undef NMT_CREATOR_IMPLEMENT
#undef CREATING_NMT

#endif // #ifdef NMT_CREATE_HEADER_NAME
#endif // #ifndef CREATING_NMT