| #ifndef SG_UNALIGNED_H |
| #define SG_UNALIGNED_H |
| |
| /* |
| * Copyright (c) 2014-2016 Douglas Gilbert. |
| * All rights reserved. |
| * Use of this source code is governed by a BSD-style |
| * license that can be found in the BSD_LICENSE file. |
| */ |
| |
| #include <stdint.h> |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| /* Borrowed from the Linux kernel, via mhvtl */ |
| |
| /* In the first section below, functions that copy unsigned integers in a |
| * computer's native format, to and from an unaligned big endian sequence of |
| * bytes. Big endian byte format "on the wire" is the default used by SCSI |
| * standards (www.t10.org). Big endian is also the network byte order. */ |
| |
| static inline uint16_t __get_unaligned_be16(const uint8_t *p) |
| { |
| return p[0] << 8 | p[1]; |
| } |
| |
| static inline uint32_t __get_unaligned_be32(const uint8_t *p) |
| { |
| return p[0] << 24 | p[1] << 16 | p[2] << 8 | p[3]; |
| } |
| |
| /* Assume 48 bit value placed in uint64_t */ |
| static inline uint64_t __get_unaligned_be48(const uint8_t *p) |
| { |
| return (uint64_t)__get_unaligned_be16(p) << 32 | |
| __get_unaligned_be32(p + 2); |
| } |
| |
| static inline uint64_t __get_unaligned_be64(const uint8_t *p) |
| { |
| return (uint64_t)__get_unaligned_be32(p) << 32 | |
| __get_unaligned_be32(p + 4); |
| } |
| |
| static inline void __put_unaligned_be16(uint16_t val, uint8_t *p) |
| { |
| *p++ = val >> 8; |
| *p++ = val; |
| } |
| |
| static inline void __put_unaligned_be32(uint32_t val, uint8_t *p) |
| { |
| __put_unaligned_be16(val >> 16, p); |
| __put_unaligned_be16(val, p + 2); |
| } |
| |
| /* Assume 48 bit value placed in uint64_t */ |
| static inline void __put_unaligned_be48(uint64_t val, uint8_t *p) |
| { |
| __put_unaligned_be16(val >> 32, p); |
| __put_unaligned_be32(val, p + 2); |
| } |
| |
| static inline void __put_unaligned_be64(uint64_t val, uint8_t *p) |
| { |
| __put_unaligned_be32(val >> 32, p); |
| __put_unaligned_be32(val, p + 4); |
| } |
| |
| static inline uint16_t sg_get_unaligned_be16(const void *p) |
| { |
| return __get_unaligned_be16((const uint8_t *)p); |
| } |
| |
| static inline uint32_t sg_get_unaligned_be24(const uint8_t *p) |
| { |
| return p[0] << 16 | p[1] << 8 | p[2]; |
| } |
| |
| static inline uint32_t sg_get_unaligned_be32(const void *p) |
| { |
| return __get_unaligned_be32((const uint8_t *)p); |
| } |
| |
| /* Assume 48 bit value placed in uint64_t */ |
| static inline uint64_t sg_get_unaligned_be48(const void *p) |
| { |
| return __get_unaligned_be48((const uint8_t *)p); |
| } |
| |
| static inline uint64_t sg_get_unaligned_be64(const void *p) |
| { |
| return __get_unaligned_be64((const uint8_t *)p); |
| } |
| |
| /* Returns 0 if 'num_bytes' is less than or equal to 0 or greater than |
| * 8 (i.e. sizeof(uint64_t)). Else returns result in uint64_t which is |
| * an 8 bytes unsigned integer. */ |
| static inline uint64_t sg_get_unaligned_be(int num_bytes, const void *p) |
| { |
| if ((num_bytes <= 0) || (num_bytes > (int)sizeof(uint64_t))) |
| return 0; |
| else { |
| const uint8_t * xp = (const uint8_t *)p; |
| uint64_t res = *xp; |
| |
| for (++xp; num_bytes > 1; ++xp, --num_bytes) |
| res = (res << 8) | *xp; |
| return res; |
| } |
| } |
| |
| static inline void sg_put_unaligned_be16(uint16_t val, void *p) |
| { |
| __put_unaligned_be16(val, (uint8_t *)p); |
| } |
| |
| static inline void sg_put_unaligned_be24(uint32_t val, void *p) |
| { |
| ((uint8_t *)p)[0] = (val >> 16) & 0xff; |
| ((uint8_t *)p)[1] = (val >> 8) & 0xff; |
| ((uint8_t *)p)[2] = val & 0xff; |
| } |
| |
| static inline void sg_put_unaligned_be32(uint32_t val, void *p) |
| { |
| __put_unaligned_be32(val, (uint8_t *)p); |
| } |
| |
| /* Assume 48 bit value placed in uint64_t */ |
| static inline void sg_put_unaligned_be48(uint64_t val, void *p) |
| { |
| __put_unaligned_be48(val, (uint8_t *)p); |
| } |
| |
| static inline void sg_put_unaligned_be64(uint64_t val, void *p) |
| { |
| __put_unaligned_be64(val, (uint8_t *)p); |
| } |
| |
| /* Since cdb and parameter blocks are often memset to zero before these |
| * unaligned function partially fill them, then check for a val of zero |
| * and ignore if it is with these variants. */ |
| static inline void sg_nz_put_unaligned_be16(uint16_t val, void *p) |
| { |
| if (val) |
| __put_unaligned_be16(val, (uint8_t *)p); |
| } |
| |
| static inline void sg_nz_put_unaligned_be24(uint32_t val, void *p) |
| { |
| if (val) { |
| ((uint8_t *)p)[0] = (val >> 16) & 0xff; |
| ((uint8_t *)p)[1] = (val >> 8) & 0xff; |
| ((uint8_t *)p)[2] = val & 0xff; |
| } |
| } |
| |
| static inline void sg_nz_put_unaligned_be32(uint32_t val, void *p) |
| { |
| if (val) |
| __put_unaligned_be32(val, (uint8_t *)p); |
| } |
| |
| static inline void sg_nz_put_unaligned_be64(uint64_t val, void *p) |
| { |
| if (val) |
| __put_unaligned_be64(val, (uint8_t *)p); |
| } |
| |
| |
| /* Below are the little endian equivalents of the big endian functions |
| * above. Little endian is used by ATA, networking and PCI. |
| */ |
| |
| static inline uint16_t __get_unaligned_le16(const uint8_t *p) |
| { |
| return p[1] << 8 | p[0]; |
| } |
| |
| static inline uint32_t __get_unaligned_le32(const uint8_t *p) |
| { |
| return p[3] << 24 | p[2] << 16 | p[1] << 8 | p[0]; |
| } |
| |
| static inline uint64_t __get_unaligned_le64(const uint8_t *p) |
| { |
| return (uint64_t)__get_unaligned_le32(p + 4) << 32 | |
| __get_unaligned_le32(p); |
| } |
| |
| static inline void __put_unaligned_le16(uint16_t val, uint8_t *p) |
| { |
| *p++ = val; |
| *p++ = val >> 8; |
| } |
| |
| static inline void __put_unaligned_le32(uint32_t val, uint8_t *p) |
| { |
| __put_unaligned_le16(val >> 16, p + 2); |
| __put_unaligned_le16(val, p); |
| } |
| |
| static inline void __put_unaligned_le64(uint64_t val, uint8_t *p) |
| { |
| __put_unaligned_le32(val >> 32, p + 4); |
| __put_unaligned_le32(val, p); |
| } |
| |
| static inline uint16_t sg_get_unaligned_le16(const void *p) |
| { |
| return __get_unaligned_le16((const uint8_t *)p); |
| } |
| |
| static inline uint32_t sg_get_unaligned_le24(const void *p) |
| { |
| return (uint32_t)__get_unaligned_le16((const uint8_t *)p) | |
| ((const uint8_t *)p)[2] << 16; |
| } |
| |
| static inline uint32_t sg_get_unaligned_le32(const void *p) |
| { |
| return __get_unaligned_le32((const uint8_t *)p); |
| } |
| |
| /* Assume 48 bit value placed in uint64_t */ |
| static inline uint64_t sg_get_unaligned_le48(const void *p) |
| { |
| return (uint64_t)__get_unaligned_le16((const uint8_t *)p + 4) << 32 | |
| __get_unaligned_le32((const uint8_t *)p); |
| } |
| |
| static inline uint64_t sg_get_unaligned_le64(const void *p) |
| { |
| return __get_unaligned_le64((const uint8_t *)p); |
| } |
| |
| /* Returns 0 if 'num_bytes' is less than or equal to 0 or greater than |
| * 8 (i.e. sizeof(uint64_t)). Else returns result in uint64_t which is |
| * an 8 bytes unsigned integer. */ |
| static inline uint64_t sg_get_unaligned_le(int num_bytes, const void *p) |
| { |
| if ((num_bytes <= 0) || (num_bytes > (int)sizeof(uint64_t))) |
| return 0; |
| else { |
| const uint8_t * xp = (const uint8_t *)p + (num_bytes - 1); |
| uint64_t res = *xp; |
| |
| for (--xp; num_bytes > 1; --xp, --num_bytes) |
| res = (res << 8) | *xp; |
| return res; |
| } |
| } |
| |
| static inline void sg_put_unaligned_le16(uint16_t val, void *p) |
| { |
| __put_unaligned_le16(val, (uint8_t *)p); |
| } |
| |
| static inline void sg_put_unaligned_le24(uint32_t val, void *p) |
| { |
| ((uint8_t *)p)[2] = (val >> 16) & 0xff; |
| ((uint8_t *)p)[1] = (val >> 8) & 0xff; |
| ((uint8_t *)p)[0] = val & 0xff; |
| } |
| |
| static inline void sg_put_unaligned_le32(uint32_t val, void *p) |
| { |
| __put_unaligned_le32(val, (uint8_t *)p); |
| } |
| |
| /* Assume 48 bit value placed in uint64_t */ |
| static inline void sg_put_unaligned_le48(uint64_t val, void *p) |
| { |
| ((uint8_t *)p)[5] = (val >> 40) & 0xff; |
| ((uint8_t *)p)[4] = (val >> 32) & 0xff; |
| ((uint8_t *)p)[3] = (val >> 24) & 0xff; |
| ((uint8_t *)p)[2] = (val >> 16) & 0xff; |
| ((uint8_t *)p)[1] = (val >> 8) & 0xff; |
| ((uint8_t *)p)[0] = val & 0xff; |
| } |
| |
| static inline void sg_put_unaligned_le64(uint64_t val, void *p) |
| { |
| __put_unaligned_le64(val, (uint8_t *)p); |
| } |
| |
| /* Since cdb and parameter blocks are often memset to zero before these |
| * unaligned function partially fill them, then check for a val of zero |
| * and ignore if it is with these variants. */ |
| static inline void sg_nz_put_unaligned_le16(uint16_t val, void *p) |
| { |
| if (val) |
| __put_unaligned_le16(val, (uint8_t *)p); |
| } |
| |
| static inline void sg_nz_put_unaligned_le24(uint32_t val, void *p) |
| { |
| if (val) { |
| ((uint8_t *)p)[2] = (val >> 16) & 0xff; |
| ((uint8_t *)p)[1] = (val >> 8) & 0xff; |
| ((uint8_t *)p)[0] = val & 0xff; |
| } |
| } |
| |
| static inline void sg_nz_put_unaligned_le32(uint32_t val, void *p) |
| { |
| if (val) |
| __put_unaligned_le32(val, (uint8_t *)p); |
| } |
| |
| static inline void sg_nz_put_unaligned_le64(uint64_t val, void *p) |
| { |
| if (val) |
| __put_unaligned_le64(val, (uint8_t *)p); |
| } |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* SG_UNALIGNED_H */ |