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author | Lasse Collin <lasse.collin@tukaani.org> | 2009-10-04 22:57:12 +0300 |
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committer | Lasse Collin <lasse.collin@tukaani.org> | 2009-10-04 22:57:12 +0300 |
commit | ebfb2c5e1f344e5c6e549b9dedaa49b0749a4a24 (patch) | |
tree | 7e2f519ad2be01b8f9c7b230f71d479d550c9ae4 /src/common/tuklib_integer.h | |
parent | Add support for --enable-assume-ram=SIZE. (diff) | |
download | xz-ebfb2c5e1f344e5c6e549b9dedaa49b0749a4a24.tar.xz |
Use a tuklib module for integer handling.
This replaces bswap.h and integer.h.
The tuklib module uses <byteswap.h> on GNU,
<sys/endian.h> on *BSDs and <sys/byteorder.h>
on Solaris, which may contain optimized code
like inline assembly.
Diffstat (limited to 'src/common/tuklib_integer.h')
-rw-r--r-- | src/common/tuklib_integer.h | 350 |
1 files changed, 350 insertions, 0 deletions
diff --git a/src/common/tuklib_integer.h b/src/common/tuklib_integer.h new file mode 100644 index 00000000..f13dd1d8 --- /dev/null +++ b/src/common/tuklib_integer.h @@ -0,0 +1,350 @@ +/////////////////////////////////////////////////////////////////////////////// +// +/// \file tuklib_integer.h +/// \brief Byte swapping and endianness related macros and functions +/// +/// This file provides macros or functions to do basic endianness related +/// integer operations (XX = 16, 32, or 64; Y = b or l): +/// - Byte swapping: bswapXX(num) +/// - Byte order conversions to/from native: convXXYe(num) +/// - Aligned reads: readXXYe(ptr) +/// - Aligned writes: writeXXYe(ptr, num) +/// - Unaligned reads (16/32-bit only): unaligned_readXXYe(ptr) +/// - Unaligned writes (16/32-bit only): unaligned_writeXXYe(ptr, num) +/// +/// Since they can macros, the arguments should have no side effects since +/// they may be evaluated more than once. +/// +/// \todo PowerPC and possibly some other architectures support +/// byte swapping load and store instructions. This file +/// doesn't take advantage of those instructions. +// +// Author: Lasse Collin +// +// This file has been put into the public domain. +// You can do whatever you want with this file. +// +/////////////////////////////////////////////////////////////////////////////// + +#ifndef TUKLIB_INTEGER_H +#define TUKLIB_INTEGER_H + +#include "tuklib_common.h" + + +//////////////////////////////////////// +// Operating system specific features // +//////////////////////////////////////// + +#if defined(HAVE_BYTESWAP_H) + // glibc, uClibc, dietlibc +# include <byteswap.h> +# ifdef HAVE_BSWAP_16 +# define bswap16(num) bswap_16(num) +# endif +# ifdef HAVE_BSWAP_32 +# define bswap32(num) bswap_32(num) +# endif +# ifdef HAVE_BSWAP_64 +# define bswap64(num) bswap_64(num) +# endif + +#elif defined(HAVE_SYS_ENDIAN_H) + // *BSDs and Darwin +# include <sys/endian.h> + +#elif defined(HAVE_SYS_BYTEORDER_H) + // Solaris +# include <sys/byteorder.h> +# ifdef BSWAP_16 +# define bswap16(num) BSWAP_16(num) +# endif +# ifdef BSWAP_32 +# define bswap32(num) BSWAP_32(num) +# endif +# ifdef BSWAP_64 +# define bswap64(num) BSWAP_64(num) +# endif +# ifdef BE_16 +# define conv16be(num) BE_16(num) +# endif +# ifdef BE_32 +# define conv32be(num) BE_32(num) +# endif +# ifdef BE_64 +# define conv64be(num) BE_64(num) +# endif +# ifdef LE_16 +# define conv16le(num) LE_16(num) +# endif +# ifdef LE_32 +# define conv32le(num) LE_32(num) +# endif +# ifdef LE_64 +# define conv64le(num) LE_64(num) +# endif +#endif + + +/////////////////// +// Byte swapping // +/////////////////// + +#ifndef bswap16 +# define bswap16(num) \ + (((uint16_t)(num) << 8) | ((uint16_t)(num) >> 8)) +#endif + +#ifndef bswap32 +# define bswap32(num) \ + ( (((uint32_t)(num) << 24) ) \ + | (((uint32_t)(num) << 8) & UINT32_C(0x00FF0000)) \ + | (((uint32_t)(num) >> 8) & UINT32_C(0x0000FF00)) \ + | (((uint32_t)(num) >> 24) ) ) +#endif + +#ifndef bswap64 +# define bswap64(num) \ + ( (((uint64_t)(num) << 56) ) \ + | (((uint64_t)(num) << 40) & UINT64_C(0x00FF000000000000)) \ + | (((uint64_t)(num) << 24) & UINT64_C(0x0000FF0000000000)) \ + | (((uint64_t)(num) << 8) & UINT64_C(0x000000FF00000000)) \ + | (((uint64_t)(num) >> 8) & UINT64_C(0x00000000FF000000)) \ + | (((uint64_t)(num) >> 24) & UINT64_C(0x0000000000FF0000)) \ + | (((uint64_t)(num) >> 40) & UINT64_C(0x000000000000FF00)) \ + | (((uint64_t)(num) >> 56) ) ) +#endif + +// Define conversion macros using the basic byte swapping macros. +#ifdef WORDS_BIGENDIAN +# ifndef conv16be +# define conv16be(num) ((uint16_t)(num)) +# endif +# ifndef conv32be +# define conv32be(num) ((uint32_t)(num)) +# endif +# ifndef conv64be +# define conv64be(num) ((uint64_t)(num)) +# endif +# ifndef conv16le +# define conv16le(num) bswap16(num) +# endif +# ifndef conv32le +# define conv32le(num) bswap32(num) +# endif +# ifndef conv64le +# define conv64le(num) bswap64(num) +# endif +#else +# ifndef conv16be +# define conv16be(num) bswap16(num) +# endif +# ifndef conv32be +# define conv32be(num) bswap32(num) +# endif +# ifndef conv64be +# define conv64be(num) bswap64(num) +# endif +# ifndef conv16le +# define conv16le(num) ((uint16_t)(num)) +# endif +# ifndef conv32le +# define conv32le(num) ((uint32_t)(num)) +# endif +# ifndef conv64le +# define conv64le(num) ((uint64_t)(num)) +# endif +#endif + + +////////////////////////////// +// Aligned reads and writes // +////////////////////////////// + +static inline uint16_t +read16be(const uint8_t *buf) +{ + uint16_t num = *(const uint16_t *)buf; + return conv16be(num); +} + + +static inline uint16_t +read16le(const uint8_t *buf) +{ + uint16_t num = *(const uint16_t *)buf; + return conv16le(num); +} + + +static inline uint32_t +read32be(const uint8_t *buf) +{ + uint32_t num = *(const uint32_t *)buf; + return conv32be(num); +} + + +static inline uint32_t +read32le(const uint8_t *buf) +{ + uint32_t num = *(const uint32_t *)buf; + return conv32le(num); +} + + +static inline uint64_t +read64be(const uint8_t *buf) +{ + uint64_t num = *(const uint64_t *)buf; + return conv64be(num); +} + + +static inline uint64_t +read64le(const uint8_t *buf) +{ + uint64_t num = *(const uint64_t *)buf; + return conv64le(num); +} + + +// NOTE: Possible byte swapping must be done in a macro to allow GCC +// to optimize byte swapping of constants when using glibc's or *BSD's +// byte swapping macros. The actual write is done in an inline function +// to make type checking of the buf pointer possible similarly to readXXYe() +// functions. This also seems to silence a probably bogus GCC warning about +// strict aliasing when buf points to the beginning of an uint8_t array. + +#define write16be(buf, num) write16ne((buf), conv16be(num)) +#define write16le(buf, num) write16ne((buf), conv16le(num)) +#define write32be(buf, num) write32ne((buf), conv32be(num)) +#define write32le(buf, num) write32ne((buf), conv32le(num)) +#define write64be(buf, num) write64ne((buf), conv64be(num)) +#define write64le(buf, num) write64ne((buf), conv64le(num)) + + +static inline void +write16ne(uint8_t *buf, uint16_t num) +{ + *(uint16_t *)buf = num; + return; +} + + +static inline void +write32ne(uint8_t *buf, uint32_t num) +{ + *(uint32_t *)buf = num; + return; +} + + +static inline void +write64ne(uint8_t *buf, uint64_t num) +{ + *(uint64_t *)buf = num; + return; +} + + +//////////////////////////////// +// Unaligned reads and writes // +//////////////////////////////// + +// NOTE: TUKLIB_FAST_UNALIGNED_ACCESS indicates only support for 16-bit and +// 32-bit unaligned integer loads and stores. It's possible that 64-bit +// unaligned access doesn't work or is slower than byte-by-byte access. +// Since unaligned 64-bit is probably not needed as often as 16-bit or +// 32-bit, we simply don't support 64-bit unaligned access for now. +#ifdef TUKLIB_FAST_UNALIGNED_ACCESS +# define unaligned_read16be read16be +# define unaligned_read16le read16le +# define unaligned_read32be read32be +# define unaligned_read32le read32le +# define unaligned_write16be write16be +# define unaligned_write16le write16le +# define unaligned_write32be write32be +# define unaligned_write32le write32le + +#else + +static inline uint16_t +unaligned_read16be(const uint8_t *buf) +{ + uint16_t num = ((uint16_t)buf[0] << 8) | buf[1]; + return num; +} + + +static inline uint16_t +unaligned_read16le(const uint8_t *buf) +{ + uint16_t num = ((uint32_t)buf[0]) | ((uint16_t)buf[1] << 8); + return num; +} + + +static inline uint32_t +unaligned_read32be(const uint8_t *buf) +{ + uint32_t num = (uint32_t)buf[0] << 24; + num |= (uint32_t)buf[1] << 16; + num |= (uint32_t)buf[2] << 8; + num |= (uint32_t)buf[3]; + return num; +} + + +static inline uint32_t +unaligned_read32le(const uint8_t *buf) +{ + uint32_t num = (uint32_t)buf[0]; + num |= (uint32_t)buf[1] << 8; + num |= (uint32_t)buf[2] << 16; + num |= (uint32_t)buf[3] << 24; + return num; +} + + +static inline void +unaligned_write16be(uint8_t *buf, uint16_t num) +{ + buf[0] = num >> 8; + buf[1] = num; + return; +} + + +static inline void +unaligned_write16le(uint8_t *buf, uint16_t num) +{ + buf[0] = num; + buf[1] = num >> 8; + return; +} + + +static inline void +unaligned_write32be(uint8_t *buf, uint32_t num) +{ + buf[0] = num >> 24; + buf[1] = num >> 16; + buf[2] = num >> 8; + buf[3] = num; + return; +} + + +static inline void +unaligned_write32le(uint8_t *buf, uint32_t num) +{ + buf[0] = num; + buf[1] = num >> 8; + buf[2] = num >> 16; + buf[3] = num >> 24; + return; +} + +#endif +#endif |