mirror of
https://github.com/vcmi/vcmi.git
synced 2024-12-20 20:23:03 +02:00
82 lines
2.1 KiB
C++
82 lines
2.1 KiB
C++
/*
|
|
* vcmi_endian.h, part of VCMI engine
|
|
*
|
|
* Authors: listed in file AUTHORS in main folder
|
|
*
|
|
* License: GNU General Public License v2.0 or later
|
|
* Full text of license available in license.txt file, in main folder
|
|
*
|
|
*/
|
|
#pragma once
|
|
|
|
#include <boost/endian/conversion.hpp> //FIXME: use std::byteswap in C++23
|
|
|
|
VCMI_LIB_NAMESPACE_BEGIN
|
|
|
|
/* Reading values from memory.
|
|
*
|
|
* read_le_u16, read_le_u32 : read a little endian value from
|
|
* memory. On big endian machines, the value will be byteswapped.
|
|
*/
|
|
|
|
#if defined(__clang__) || defined(__GNUC__) || defined(_MSC_VER)
|
|
|
|
#if defined(_MSC_VER)
|
|
#define PACKED_STRUCT_BEGIN __pragma( pack(push, 1) )
|
|
#define PACKED_STRUCT_END __pragma( pack(pop) )
|
|
#else
|
|
#define PACKED_STRUCT_BEGIN
|
|
#define PACKED_STRUCT_END __attribute__(( packed ))
|
|
#endif
|
|
|
|
PACKED_STRUCT_BEGIN struct unaligned_Uint16 { ui16 val; } PACKED_STRUCT_END;
|
|
PACKED_STRUCT_BEGIN struct unaligned_Uint32 { ui32 val; } PACKED_STRUCT_END;
|
|
|
|
static inline ui16 read_unaligned_u16(const void *p)
|
|
{
|
|
const auto * v = reinterpret_cast<const struct unaligned_Uint16 *>(p);
|
|
return v->val;
|
|
}
|
|
|
|
static inline ui32 read_unaligned_u32(const void *p)
|
|
{
|
|
const auto * v = reinterpret_cast<const struct unaligned_Uint32 *>(p);
|
|
return v->val;
|
|
}
|
|
|
|
#define read_le_u16(p) (boost::endian::native_to_little(read_unaligned_u16(p)))
|
|
#define read_le_u32(p) (boost::endian::native_to_little(read_unaligned_u32(p)))
|
|
|
|
#else
|
|
|
|
#warning UB: unaligned memory access
|
|
|
|
#define read_le_u16(p) (boost::endian::native_to_little(* reinterpret_cast<const ui16 *>(p)))
|
|
#define read_le_u32(p) (boost::endian::native_to_little(* reinterpret_cast<const ui32 *>(p)))
|
|
|
|
#define PACKED_STRUCT_BEGIN
|
|
#define PACKED_STRUCT_END
|
|
|
|
#endif
|
|
|
|
static inline char readChar(const ui8 * buffer, int & i)
|
|
{
|
|
return buffer[i++];
|
|
}
|
|
|
|
static inline std::string readString(const ui8 * buffer, int & i)
|
|
{
|
|
int len = read_le_u32(buffer + i);
|
|
i += 4;
|
|
assert(len >= 0 && len <= 500000); //not too long
|
|
std::string ret;
|
|
ret.reserve(len);
|
|
for(int gg = 0; gg < len; ++gg)
|
|
{
|
|
ret += buffer[i++];
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
VCMI_LIB_NAMESPACE_END
|