2015-10-08 19:01:36 +02:00
|
|
|
/*-------------------------------------------------------------------------
|
|
|
|
*
|
|
|
|
* pg_bswap.h
|
|
|
|
* Byte swapping.
|
|
|
|
*
|
2017-09-30 00:52:55 +02:00
|
|
|
* Macros for reversing the byte order of 16, 32 and 64-bit unsigned integers.
|
2015-10-08 19:01:36 +02:00
|
|
|
* For example, 0xAABBCCDD becomes 0xDDCCBBAA. These are just wrappers for
|
|
|
|
* built-in functions provided by the compiler where support exists.
|
|
|
|
*
|
2017-09-30 00:52:55 +02:00
|
|
|
* Note that all of these functions accept unsigned integers as arguments and
|
|
|
|
* return the same. Use caution when using these wrapper macros with signed
|
|
|
|
* integers.
|
2015-10-08 19:01:36 +02:00
|
|
|
*
|
2023-01-02 21:00:37 +01:00
|
|
|
* Copyright (c) 2015-2023, PostgreSQL Global Development Group
|
2015-10-08 19:01:36 +02:00
|
|
|
*
|
|
|
|
* src/include/port/pg_bswap.h
|
|
|
|
*
|
|
|
|
*-------------------------------------------------------------------------
|
|
|
|
*/
|
|
|
|
#ifndef PG_BSWAP_H
|
|
|
|
#define PG_BSWAP_H
|
|
|
|
|
2017-09-30 00:52:55 +02:00
|
|
|
|
2017-10-02 00:24:14 +02:00
|
|
|
/*
|
|
|
|
* In all supported versions msvc provides _byteswap_* functions in stdlib.h,
|
|
|
|
* already included by c.h.
|
|
|
|
*/
|
2017-09-30 00:52:55 +02:00
|
|
|
|
|
|
|
|
|
|
|
/* implementation of uint16 pg_bswap16(uint16) */
|
|
|
|
#if defined(HAVE__BUILTIN_BSWAP16)
|
|
|
|
|
|
|
|
#define pg_bswap16(x) __builtin_bswap16(x)
|
|
|
|
|
|
|
|
#elif defined(_MSC_VER)
|
|
|
|
|
|
|
|
#define pg_bswap16(x) _byteswap_ushort(x)
|
|
|
|
|
|
|
|
#else
|
|
|
|
|
|
|
|
static inline uint16
|
|
|
|
pg_bswap16(uint16 x)
|
|
|
|
{
|
|
|
|
return
|
|
|
|
((x << 8) & 0xff00) |
|
|
|
|
((x >> 8) & 0x00ff);
|
|
|
|
}
|
|
|
|
|
|
|
|
#endif /* HAVE__BUILTIN_BSWAP16 */
|
|
|
|
|
|
|
|
|
|
|
|
/* implementation of uint32 pg_bswap32(uint32) */
|
|
|
|
#if defined(HAVE__BUILTIN_BSWAP32)
|
|
|
|
|
|
|
|
#define pg_bswap32(x) __builtin_bswap32(x)
|
|
|
|
|
|
|
|
#elif defined(_MSC_VER)
|
|
|
|
|
|
|
|
#define pg_bswap32(x) _byteswap_ulong(x)
|
|
|
|
|
2015-10-08 19:01:36 +02:00
|
|
|
#else
|
2017-09-30 00:52:55 +02:00
|
|
|
|
|
|
|
static inline uint32
|
|
|
|
pg_bswap32(uint32 x)
|
|
|
|
{
|
|
|
|
return
|
|
|
|
((x << 24) & 0xff000000) |
|
|
|
|
((x << 8) & 0x00ff0000) |
|
|
|
|
((x >> 8) & 0x0000ff00) |
|
|
|
|
((x >> 24) & 0x000000ff);
|
|
|
|
}
|
|
|
|
|
2015-10-09 21:06:06 +02:00
|
|
|
#endif /* HAVE__BUILTIN_BSWAP32 */
|
2015-10-08 19:01:36 +02:00
|
|
|
|
2017-09-30 00:52:55 +02:00
|
|
|
|
|
|
|
/* implementation of uint64 pg_bswap64(uint64) */
|
|
|
|
#if defined(HAVE__BUILTIN_BSWAP64)
|
|
|
|
|
|
|
|
#define pg_bswap64(x) __builtin_bswap64(x)
|
|
|
|
|
|
|
|
|
|
|
|
#elif defined(_MSC_VER)
|
|
|
|
|
|
|
|
#define pg_bswap64(x) _byteswap_uint64(x)
|
|
|
|
|
2015-10-08 19:01:36 +02:00
|
|
|
#else
|
2017-09-30 00:52:55 +02:00
|
|
|
|
2017-09-30 02:41:20 +02:00
|
|
|
static inline uint64
|
|
|
|
pg_bswap64(uint64 x)
|
2017-09-30 00:52:55 +02:00
|
|
|
{
|
|
|
|
return
|
|
|
|
((x << 56) & UINT64CONST(0xff00000000000000)) |
|
|
|
|
((x << 40) & UINT64CONST(0x00ff000000000000)) |
|
|
|
|
((x << 24) & UINT64CONST(0x0000ff0000000000)) |
|
|
|
|
((x << 8) & UINT64CONST(0x000000ff00000000)) |
|
|
|
|
((x >> 8) & UINT64CONST(0x00000000ff000000)) |
|
|
|
|
((x >> 24) & UINT64CONST(0x0000000000ff0000)) |
|
|
|
|
((x >> 40) & UINT64CONST(0x000000000000ff00)) |
|
|
|
|
((x >> 56) & UINT64CONST(0x00000000000000ff));
|
|
|
|
}
|
2015-10-09 21:06:06 +02:00
|
|
|
#endif /* HAVE__BUILTIN_BSWAP64 */
|
|
|
|
|
2017-09-30 00:52:55 +02:00
|
|
|
|
|
|
|
/*
|
2018-07-09 15:10:44 +02:00
|
|
|
* Portable and fast equivalents for ntohs, ntohl, htons, htonl,
|
2017-09-30 00:52:55 +02:00
|
|
|
* additionally extended to 64 bits.
|
|
|
|
*/
|
|
|
|
#ifdef WORDS_BIGENDIAN
|
|
|
|
|
|
|
|
#define pg_hton16(x) (x)
|
|
|
|
#define pg_hton32(x) (x)
|
|
|
|
#define pg_hton64(x) (x)
|
|
|
|
|
|
|
|
#define pg_ntoh16(x) (x)
|
|
|
|
#define pg_ntoh32(x) (x)
|
|
|
|
#define pg_ntoh64(x) (x)
|
|
|
|
|
|
|
|
#else
|
|
|
|
|
|
|
|
#define pg_hton16(x) pg_bswap16(x)
|
|
|
|
#define pg_hton32(x) pg_bswap32(x)
|
|
|
|
#define pg_hton64(x) pg_bswap64(x)
|
|
|
|
|
|
|
|
#define pg_ntoh16(x) pg_bswap16(x)
|
|
|
|
#define pg_ntoh32(x) pg_bswap32(x)
|
|
|
|
#define pg_ntoh64(x) pg_bswap64(x)
|
|
|
|
|
|
|
|
#endif /* WORDS_BIGENDIAN */
|
|
|
|
|
|
|
|
|
2015-10-09 21:06:06 +02:00
|
|
|
/*
|
|
|
|
* Rearrange the bytes of a Datum from big-endian order into the native byte
|
|
|
|
* order. On big-endian machines, this does nothing at all. Note that the C
|
|
|
|
* type Datum is an unsigned integer type on all platforms.
|
|
|
|
*
|
|
|
|
* One possible application of the DatumBigEndianToNative() macro is to make
|
|
|
|
* bitwise comparisons cheaper. A simple 3-way comparison of Datums
|
|
|
|
* transformed by the macro (based on native, unsigned comparisons) will return
|
|
|
|
* the same result as a memcmp() of the corresponding original Datums, but can
|
|
|
|
* be much cheaper. It's generally safe to do this on big-endian systems
|
|
|
|
* without any special transformation occurring first.
|
2019-10-19 18:21:58 +02:00
|
|
|
*
|
|
|
|
* If SIZEOF_DATUM is not defined, then postgres.h wasn't included and these
|
|
|
|
* macros probably shouldn't be used, so we define nothing. Note that
|
|
|
|
* SIZEOF_DATUM == 8 would evaluate as 0 == 8 in that case, potentially
|
|
|
|
* leading to the wrong implementation being selected and confusing errors, so
|
|
|
|
* defining nothing is safest.
|
2015-10-09 21:06:06 +02:00
|
|
|
*/
|
2019-10-19 18:21:58 +02:00
|
|
|
#ifdef SIZEOF_DATUM
|
2015-10-09 21:06:06 +02:00
|
|
|
#ifdef WORDS_BIGENDIAN
|
|
|
|
#define DatumBigEndianToNative(x) (x)
|
|
|
|
#else /* !WORDS_BIGENDIAN */
|
|
|
|
#if SIZEOF_DATUM == 8
|
2017-09-30 00:52:55 +02:00
|
|
|
#define DatumBigEndianToNative(x) pg_bswap64(x)
|
2015-10-09 21:06:06 +02:00
|
|
|
#else /* SIZEOF_DATUM != 8 */
|
2017-09-30 00:52:55 +02:00
|
|
|
#define DatumBigEndianToNative(x) pg_bswap32(x)
|
2015-10-09 21:06:06 +02:00
|
|
|
#endif /* SIZEOF_DATUM == 8 */
|
|
|
|
#endif /* WORDS_BIGENDIAN */
|
2019-10-19 18:21:58 +02:00
|
|
|
#endif /* SIZEOF_DATUM */
|
2015-10-08 19:01:36 +02:00
|
|
|
|
|
|
|
#endif /* PG_BSWAP_H */
|