OpenTTD-patches/src/saveload/oldloader.h

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/*
* This file is part of OpenTTD.
* OpenTTD 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, version 2.
* OpenTTD 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 OpenTTD. If not, see <http://www.gnu.org/licenses/>.
*/
/** @file oldloader.h Declarations of strctures and function used in loader of old savegames */
#ifndef OLDLOADER_H
#define OLDLOADER_H
#include "saveload.h"
#include "../tile_type.h"
static const uint BUFFER_SIZE = 4096;
static const uint OLD_MAP_SIZE = 256 * 256;
struct LoadgameState {
FILE *file;
uint chunk_size;
bool decoding;
byte decode_char;
uint buffer_count;
uint buffer_cur;
byte buffer[BUFFER_SIZE];
uint total_read;
};
/* OldChunk-Type */
enum OldChunkType {
OC_SIMPLE = 0,
OC_NULL = 1,
OC_CHUNK = 2,
OC_ASSERT = 3,
/* 4 bits allocated (16 max) */
OC_TTD = 1 << 4, ///< chunk is valid ONLY for TTD savegames
OC_TTO = 1 << 5, ///< -//- TTO (default is neither of these)
/* 4 bits allocated */
OC_VAR_I8 = 1 << 8,
OC_VAR_U8 = 2 << 8,
OC_VAR_I16 = 3 << 8,
OC_VAR_U16 = 4 << 8,
OC_VAR_I32 = 5 << 8,
OC_VAR_U32 = 6 << 8,
OC_VAR_I64 = 7 << 8,
OC_VAR_U64 = 8 << 8,
/* 8 bits allocated (256 max) */
OC_FILE_I8 = 1 << 16,
OC_FILE_U8 = 2 << 16,
OC_FILE_I16 = 3 << 16,
OC_FILE_U16 = 4 << 16,
OC_FILE_I32 = 5 << 16,
OC_FILE_U32 = 6 << 16,
/* 8 bits allocated (256 max) */
OC_INT8 = OC_VAR_I8 | OC_FILE_I8,
OC_UINT8 = OC_VAR_U8 | OC_FILE_U8,
OC_INT16 = OC_VAR_I16 | OC_FILE_I16,
OC_UINT16 = OC_VAR_U16 | OC_FILE_U16,
OC_INT32 = OC_VAR_I32 | OC_FILE_I32,
OC_UINT32 = OC_VAR_U32 | OC_FILE_U32,
OC_TILE = OC_VAR_U32 | OC_FILE_U16,
/**
* Dereference the pointer once before writing to it,
* so we do not have to use big static arrays.
*/
OC_DEREFERENCE_POINTER = 1 << 31,
OC_END = 0, ///< End of the whole chunk, all 32 bits set to zero
};
DECLARE_ENUM_AS_BIT_SET(OldChunkType)
typedef bool OldChunkProc(LoadgameState *ls, int num);
struct OldChunks {
OldChunkType type; ///< Type of field
uint32 amount; ///< Amount of fields
void *ptr; ///< Pointer where to save the data (may only be set if offset is 0)
uint offset; ///< Offset from basepointer (may only be set if ptr is nullptr)
OldChunkProc *proc; ///< Pointer to function that is called with OC_CHUNK
};
/* If it fails, check lines above.. */
assert_compile(sizeof(TileIndex) == 4);
extern uint _bump_assert_value;
byte ReadByte(LoadgameState *ls);
bool LoadChunk(LoadgameState *ls, void *base, const OldChunks *chunks);
bool LoadTTDMain(LoadgameState *ls);
bool LoadTTOMain(LoadgameState *ls);
static inline uint16 ReadUint16(LoadgameState *ls)
{
byte x = ReadByte(ls);
return x | ReadByte(ls) << 8;
}
static inline uint32 ReadUint32(LoadgameState *ls)
{
uint16 x = ReadUint16(ls);
return x | ReadUint16(ls) << 16;
}
/* Help:
* - OCL_SVAR: load 'type' to offset 'offset' in a struct of type 'base', which must also
* be given via base in LoadChunk() as real pointer
* - OCL_VAR: load 'type' to a global var
* - OCL_END: every struct must end with this
* - OCL_NULL: read 'amount' of bytes and send them to /dev/null or something
2010-01-01 18:45:40 +00:00
* - OCL_CHUNK: load another proc to load a part of the savegame, 'amount' times
* - OCL_ASSERT: to check if we are really at the place we expect to be.. because old savegames are too binary to be sure ;)
*/
#define OCL_SVAR(type, base, offset) { type, 1, nullptr, (uint)cpp_offsetof(base, offset), nullptr }
#define OCL_VAR(type, amount, pointer) { type, amount, pointer, 0, nullptr }
#define OCL_END() { OC_END, 0, nullptr, 0, nullptr }
#define OCL_CNULL(type, amount) { OC_NULL | type, amount, nullptr, 0, nullptr }
#define OCL_CCHUNK(type, amount, proc) { OC_CHUNK | type, amount, nullptr, 0, proc }
#define OCL_ASSERT(type, size) { OC_ASSERT | type, 1, nullptr, size, nullptr }
#define OCL_NULL(amount) OCL_CNULL((OldChunkType)0, amount)
#define OCL_CHUNK(amount, proc) OCL_CCHUNK((OldChunkType)0, amount, proc)
#endif /* OLDLOADER_H */