Files
foobar2000-sdk/pfc/byte_order.h
2021-12-14 00:28:25 -07:00

257 lines
8.7 KiB
C++

#pragma once
namespace pfc {
void byteswap_raw(void * p_buffer,t_size p_bytes);
template<typename T> T byteswap_t(T p_source);
template<> inline char byteswap_t<char>(char p_source) {return p_source;}
template<> inline unsigned char byteswap_t<unsigned char>(unsigned char p_source) {return p_source;}
template<> inline signed char byteswap_t<signed char>(signed char p_source) {return p_source;}
template<typename T> T byteswap_int_t(T p_source) {
enum { width = sizeof(T) };
typedef typename sized_int_t<width>::t_unsigned tU;
tU in = p_source, out = 0;
for(unsigned walk = 0; walk < width; ++walk) {
out |= ((in >> (walk * 8)) & 0xFF) << ((width - 1 - walk) * 8);
}
return out;
}
#ifdef _MSC_VER//does this even help with performance/size?
template<> inline wchar_t byteswap_t<wchar_t>(wchar_t p_source) {return _byteswap_ushort(p_source);}
template<> inline short byteswap_t<short>(short p_source) {return _byteswap_ushort(p_source);}
template<> inline unsigned short byteswap_t<unsigned short>(unsigned short p_source) {return _byteswap_ushort(p_source);}
template<> inline int byteswap_t<int>(int p_source) {return _byteswap_ulong(p_source);}
template<> inline unsigned int byteswap_t<unsigned int>(unsigned int p_source) {return _byteswap_ulong(p_source);}
template<> inline long byteswap_t<long>(long p_source) {return _byteswap_ulong(p_source);}
template<> inline unsigned long byteswap_t<unsigned long>(unsigned long p_source) {return _byteswap_ulong(p_source);}
template<> inline long long byteswap_t<long long>(long long p_source) {return _byteswap_uint64(p_source);}
template<> inline unsigned long long byteswap_t<unsigned long long>(unsigned long long p_source) {return _byteswap_uint64(p_source);}
#else
template<> inline wchar_t byteswap_t<wchar_t>(wchar_t p_source) {return byteswap_int_t(p_source);}
template<> inline short byteswap_t<short>(short p_source) {return byteswap_int_t(p_source);}
template<> inline unsigned short byteswap_t<unsigned short>(unsigned short p_source) {return byteswap_int_t(p_source);}
template<> inline int byteswap_t<int>(int p_source) {return byteswap_int_t(p_source);}
template<> inline unsigned int byteswap_t<unsigned int>(unsigned int p_source) {return byteswap_int_t(p_source);}
template<> inline long byteswap_t<long>(long p_source) {return byteswap_int_t(p_source);}
template<> inline unsigned long byteswap_t<unsigned long>(unsigned long p_source) {return byteswap_int_t(p_source);}
template<> inline long long byteswap_t<long long>(long long p_source) {return byteswap_int_t(p_source);}
template<> inline unsigned long long byteswap_t<unsigned long long>(unsigned long long p_source) {return byteswap_int_t(p_source);}
#endif
template<> inline float byteswap_t<float>(float p_source) {
float ret;
*(t_uint32*) &ret = byteswap_t(*(const t_uint32*)&p_source );
return ret;
}
template<> inline double byteswap_t<double>(double p_source) {
double ret;
*(t_uint64*) &ret = byteswap_t(*(const t_uint64*)&p_source );
return ret;
}
//blargh at GUID byteswap issue
template<> inline GUID byteswap_t<GUID>(GUID p_guid) {
GUID ret;
ret.Data1 = pfc::byteswap_t(p_guid.Data1);
ret.Data2 = pfc::byteswap_t(p_guid.Data2);
ret.Data3 = pfc::byteswap_t(p_guid.Data3);
ret.Data4[0] = p_guid.Data4[0];
ret.Data4[1] = p_guid.Data4[1];
ret.Data4[2] = p_guid.Data4[2];
ret.Data4[3] = p_guid.Data4[3];
ret.Data4[4] = p_guid.Data4[4];
ret.Data4[5] = p_guid.Data4[5];
ret.Data4[6] = p_guid.Data4[6];
ret.Data4[7] = p_guid.Data4[7];
return ret;
}
#if ! defined(_MSC_VER) || _MSC_VER >= 1900
template<> inline char16_t byteswap_t<char16_t>(char16_t v) { return (char16_t)byteswap_t((uint16_t)v); }
template<> inline char32_t byteswap_t<char32_t>(char32_t v) { return (char32_t)byteswap_t((uint32_t)v); }
#endif
};
#ifdef _MSC_VER
#if defined(_M_IX86) || defined(_M_X64) || defined(_M_ARM)
#define PFC_BYTE_ORDER_IS_BIG_ENDIAN 0
#endif
#else//_MSC_VER
#if defined(__APPLE__)
#include <architecture/byte_order.h>
#else
#include <endian.h>
#endif
#if __BYTE_ORDER == __LITTLE_ENDIAN
#define PFC_BYTE_ORDER_IS_BIG_ENDIAN 0
#else
#define PFC_BYTE_ORDER_IS_BIG_ENDIAN 1
#endif
#endif//_MSC_VER
#ifdef PFC_BYTE_ORDER_IS_BIG_ENDIAN
#define PFC_BYTE_ORDER_IS_LITTLE_ENDIAN (!(PFC_BYTE_ORDER_IS_BIG_ENDIAN))
#else
#error please update byte order #defines
#endif
namespace pfc {
static const bool byte_order_is_big_endian = !!PFC_BYTE_ORDER_IS_BIG_ENDIAN;
static const bool byte_order_is_little_endian = !!PFC_BYTE_ORDER_IS_LITTLE_ENDIAN;
template<typename T> T byteswap_if_be_t(T p_param) {return byte_order_is_big_endian ? byteswap_t(p_param) : p_param;}
template<typename T> T byteswap_if_le_t(T p_param) {return byte_order_is_little_endian ? byteswap_t(p_param) : p_param;}
}
namespace byte_order {
#if PFC_BYTE_ORDER_IS_BIG_ENDIAN//big endian
template<typename T> inline void order_native_to_le_t(T& param) {param = pfc::byteswap_t(param);}
template<typename T> inline void order_native_to_be_t(T& param) {}
template<typename T> inline void order_le_to_native_t(T& param) {param = pfc::byteswap_t(param);}
template<typename T> inline void order_be_to_native_t(T& param) {}
#else//little endian
template<typename T> inline void order_native_to_le_t(T& param) {}
template<typename T> inline void order_native_to_be_t(T& param) {param = pfc::byteswap_t(param);}
template<typename T> inline void order_le_to_native_t(T& param) {}
template<typename T> inline void order_be_to_native_t(T& param) {param = pfc::byteswap_t(param);}
#endif
};
namespace pfc {
template<typename TInt,unsigned width,bool IsBigEndian>
class __EncodeIntHelper {
public:
inline static void Run(TInt p_value,t_uint8 * p_out) {
*p_out = (t_uint8)(p_value);
__EncodeIntHelper<TInt,width-1,IsBigEndian>::Run(p_value >> 8,p_out + (IsBigEndian ? -1 : 1));
}
};
template<typename TInt,bool IsBigEndian>
class __EncodeIntHelper<TInt,1,IsBigEndian> {
public:
inline static void Run(TInt p_value,t_uint8* p_out) {
*p_out = (t_uint8)(p_value);
}
};
template<typename TInt,bool IsBigEndian>
class __EncodeIntHelper<TInt,0,IsBigEndian> {
public:
inline static void Run(TInt,t_uint8*) {}
};
template<typename TInt>
inline void encode_little_endian(t_uint8 * p_buffer,TInt p_value) {
__EncodeIntHelper<TInt,sizeof(TInt),false>::Run(p_value,p_buffer);
}
template<typename TInt>
inline void encode_big_endian(t_uint8 * p_buffer,TInt p_value) {
__EncodeIntHelper<TInt,sizeof(TInt),true>::Run(p_value,p_buffer + (sizeof(TInt) - 1));
}
template<typename TInt,unsigned width,bool IsBigEndian>
class __DecodeIntHelper {
public:
inline static TInt Run(const t_uint8 * p_in) {
return (__DecodeIntHelper<TInt,width-1,IsBigEndian>::Run(p_in + (IsBigEndian ? -1 : 1)) << 8) + *p_in;
}
};
template<typename TInt,bool IsBigEndian>
class __DecodeIntHelper<TInt,1,IsBigEndian> {
public:
inline static TInt Run(const t_uint8* p_in) {return *p_in;}
};
template<typename TInt,bool IsBigEndian>
class __DecodeIntHelper<TInt,0,IsBigEndian> {
public:
inline static TInt Run(const t_uint8*) {return 0;}
};
template<typename TInt>
inline void decode_little_endian(TInt & p_out,const t_uint8 * p_buffer) {
p_out = __DecodeIntHelper<TInt,sizeof(TInt),false>::Run(p_buffer);
}
template<typename TInt>
inline void decode_big_endian(TInt & p_out,const t_uint8 * p_buffer) {
p_out = __DecodeIntHelper<TInt,sizeof(TInt),true>::Run(p_buffer + (sizeof(TInt) - 1));
}
template<typename TInt>
inline TInt decode_little_endian(const t_uint8 * p_buffer) {
TInt temp;
decode_little_endian(temp,p_buffer);
return temp;
}
template<typename TInt>
inline TInt decode_big_endian(const t_uint8 * p_buffer) {
TInt temp;
decode_big_endian(temp,p_buffer);
return temp;
}
template<bool IsBigEndian,typename TInt>
inline void decode_endian(TInt & p_out,const t_uint8 * p_buffer) {
if (IsBigEndian) decode_big_endian(p_out,p_buffer);
else decode_little_endian(p_out,p_buffer);
}
template<bool IsBigEndian,typename TInt>
inline void encode_endian(t_uint8 * p_buffer,TInt p_in) {
if (IsBigEndian) encode_big_endian(p_in,p_buffer);
else encode_little_endian(p_in,p_buffer);
}
template<unsigned width>
inline void reverse_bytes(t_uint8 * p_buffer) {
pfc::swap_t(p_buffer[0],p_buffer[width-1]);
reverse_bytes<width-2>(p_buffer+1);
}
template<> inline void reverse_bytes<1>(t_uint8 * ) { }
template<> inline void reverse_bytes<0>(t_uint8 * ) { }
inline int32_t readInt24(const void * mem) {
const uint8_t * p = (const uint8_t*) mem;
int32_t ret;
if (byte_order_is_little_endian) {
ret = p[0];
ret |= (uint32_t)p[1] << 8;
ret |= (int32_t)(int8_t)p[2] << 16;
return ret;
} else {
ret = p[2];
ret |= (uint32_t)p[1] << 8;
ret |= (int32_t)(int8_t)p[0] << 16;
return ret;
}
}
}