source/network/Serialization.h

   1 /* Copyright (C) 2015 Wildfire Games.
   2  * This file is part of 0 A.D.
   3  *
   4  * 0 A.D. is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * 0 A.D. is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with 0 A.D.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #ifndef INCLUDED_NETWORK_SERIALIZATION
  19 #define INCLUDED_NETWORK_SERIALIZATION
  20
  21 #define Serialize_int_1(_pos, _val) \
  22         STMT( *((_pos)++) = (u8)((_val)&0xff); )
  23
  24 #define Serialize_int_2(_pos, _val) STMT(\
  25         Serialize_int_1(_pos, (_val)>>8); \
  26         Serialize_int_1(_pos, (_val)); \
  27 )
  28
  29 #define Serialize_int_3(_pos, _val) STMT(\
  30         Serialize_int_1(_pos, (_val)>>16); \
  31         Serialize_int_2(_pos, (_val)); \
  32 )
  33
  34 #define Serialize_int_4(_pos, _val) STMT(\
  35         Serialize_int_1(_pos, (_val)>>24); \
  36         Serialize_int_3(_pos, (_val)); \
  37 )
  38
  39 #define Serialize_int_8(_pos, _val) STMT(\
  40         Serialize_int_4(_pos, (_val)>>32); \
  41         Serialize_int_4(_pos, (_val)); \
  42 )
  43
  44 #define __shift_de(_pos, _val) STMT( \
  45         (_val) <<= 8; \
  46         (_val) += *((_pos)++); )
  47
  48 #define Deserialize_int_1(_pos, _val) STMT(\
  49         (_val) = *((_pos)++); )
  50
  51 #define Deserialize_int_2(_pos, _val) STMT(\
  52         Deserialize_int_1(_pos, _val); \
  53         __shift_de(_pos, _val); )
  54
  55 #define Deserialize_int_3(_pos, _val) STMT(\
  56         Deserialize_int_2(_pos, _val); \
  57         __shift_de(_pos, _val); )
  58
  59 #define Deserialize_int_4(_pos, _val) STMT(\
  60         Deserialize_int_3(_pos, _val); \
  61         __shift_de(_pos, _val); )
  62
  63 #define Deserialize_int_8(_pos, _val) STMT(\
  64         uint32 _v1; uint32 _v2; \
  65         Deserialize_int_4(_pos, _v1); \
  66         Deserialize_int_4(_pos, _v2); \
  67         _val = _v1; \
  68         _val <<= 32;    /* janwas: careful! (uint32 << 32) = 0 */ \
  69         _val |= _v2; )
  70
  71 /**
  72  * An interface for serializable objects. For a serializable object to be usable
  73  * as a network message field, it must have a constructor without arguments.
  74  */
  75 class ISerializable
  76 {
  77 public:
  78         virtual ~ISerializable() {}
  79
  80         /**
  81          * Return the length of the serialized form of this object
  82          */
  83         virtual size_t GetSerializedLength() const = 0;
  84         /**
  85          * Serialize the object into the passed buffer.
  86          *
  87          * @return a pointer to the location in the buffer right after the
  88          * serialized object
  89          */
  90         virtual u8 *Serialize(u8 *buffer) const = 0;
  91         /**
  92          * Deserialize the object (i.e. read in data from the buffer and initialize
  93          * the object's fields). Note that it is up to the deserializer to detect
  94          * errors in data format.
  95          *
  96          * @param buffer A pointer pointing to the start of the serialized data.
  97          * @param end A pointer to the end of the message.
  98          *
  99          * @returns a pointer to the location in the buffer right after the
 100          * serialized object, or NULL if there was a data format error
 101          */
 102         virtual const u8 *Deserialize(const u8 *buffer, const u8 *end) = 0;
 103 };
 104
 105 #endif