diff options
Diffstat (limited to 'os/various/bswap.h')
| -rw-r--r-- | os/various/bswap.h | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/os/various/bswap.h b/os/various/bswap.h new file mode 100644 index 0000000..b99034e --- /dev/null +++ b/os/various/bswap.h @@ -0,0 +1,129 @@ +#ifndef BSWAP_H +#define BSWAP_H + +#if defined(__cplusplus) +extern "C" { +#endif + +#if !(defined(ARCH_BIG_ENDIAN) || defined(ARCH_LITTLE_ENDIAN)) +#error "ARCH_BIG_ENDIAN or ARCH_LITTLE_ENDIAN not set." +#endif + +#if defined(ARCH_BIG_ENDIAN) && defined(ARCH_LITTLE_ENDIAN) +#error "ARCH_BIG_ENDIAN and ARCH_LITTLE_ENDIAN are both set." +#endif + + +#define BSWAP_16(x) \ + (uint16_t)((((x) & 0xFF00) >> 8) | (((x) & 0x00FF) << 8)) +#define BSWAP_32(x) \ + (uint32_t)((((x) & 0xFF000000UL) >> 24UL) | \ + (((x) & 0x00FF0000UL) >> 8UL) | \ + (((x) & 0x0000FF00UL) << 8UL) | \ + (((x) & 0x000000FFUL) << 24UL)) + + +#if defined(ARCH_BIG_ENDIAN) +#define le16_to_cpu(x) bswap_16(x) +#define le32_to_cpu(x) bswap_32(x) +#define be16_to_cpu(x) (x) +#define be32_to_cpu(x) (x) +#define cpu_to_le16(x) bswap_16(x) +#define cpu_to_le32(x) bswap_32(x) +#define cpu_to_be16(x) (x) +#define cpu_to_be32(x) (x) +#define LE16_TO_CPU(x) BSWAP_16(x) +#define LE32_TO_CPU(x) BSWAP_32(x) +#define BE16_TO_CPU(x) (x) +#define BE32_TO_CPU(x) (x) +#define CPU_TO_LE16(x) BSWAP_16(x) +#define CPU_TO_LE32(x) BSWAP_32(x) +#define CPU_TO_BE16(x) (x) +#define CPU_TO_BE32(x) (x) +#endif + + +#if defined(ARCH_LITTLE_ENDIAN) +#define le16_to_cpu(x) (x) +#define le32_to_cpu(x) (x) +#define be16_to_cpu(x) bswap_16(x) +#define be32_to_cpu(x) bswap_32(x) +#define cpu_to_le16(x) (x) +#define cpu_to_le32(x) (x) +#define cpu_to_be16(x) bswap_16(x) +#define cpu_to_be32(x) bswap_32(x) +#define LE16_TO_CPU(x) (x) +#define LE32_TO_CPU(x) (x) +#define BE16_TO_CPU(x) BSWAP_16(x) +#define BE32_TO_CPU(x) BSWAP_32(x) +#define CPU_TO_LE16(x) (x) +#define CPU_TO_LE32(x) (x) +#define CPU_TO_BE16(x) BSWAP_16(x) +#define CPU_TO_BE32(x) BSWAP_32(x) +#endif + + +static inline uint16_t bswap_16(const uint16_t x) + __attribute__ ((warn_unused_result)) + __attribute__ ((const)) + __attribute__ ((always_inline)); + +static inline uint16_t bswap_16(const uint16_t x) { + if (__builtin_constant_p(x)) + return BSWAP_16(x); + + uint8_t tmp; + union { uint16_t x; uint8_t b[2]; } data; + + data.x = x; + tmp = data.b[0]; + data.b[0] = data.b[1]; + data.b[1] = tmp; + + return data.x; +} + +static inline uint32_t bswap_32(const uint32_t x) + __attribute__ ((warn_unused_result)) + __attribute__ ((const)) + __attribute__ ((always_inline)); + + +static inline uint32_t bswap_32(const uint32_t x) { + if (__builtin_constant_p(x)) + return BSWAP_32(x); + + uint8_t tmp; + union { uint32_t x; uint8_t b[4]; } data; + + data.x = x; + tmp = data.b[0]; + data.b[0] = data.b[3]; + data.b[3] = tmp; + tmp = data.b[1]; + data.b[1] = data.b[2]; + data.b[2] = tmp; + + return data.x; +} + +static inline void bswap_n(void* const data, uint8_t len) + __attribute__ ((nonnull (1))); + +static inline void bswap_n(void* const data, uint8_t len) { + uint8_t* ptr = (uint8_t*)data; + + for ( ; len > 1 ; ptr++, len -= 2 ) { + uint8_t tmp = *ptr; + *ptr = *(ptr + len - 1); + *(ptr + len - 1) = tmp; + } +} + +#if defined(__cplusplus) +} +#endif + +#endif + + |