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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-15 17:14:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-15 17:14:45 +0000 |
commit | 43e8530e93493bb978c446a2023134bdd4277e50 (patch) | |
tree | e8c0d3c0c394b17381f48fb2d288f166b4f22440 /sg_unaligned.h | |
parent | Initial commit. (diff) | |
download | smartmontools-upstream.tar.xz smartmontools-upstream.zip |
Adding upstream version 7.4.upstream/7.4upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'sg_unaligned.h')
-rw-r--r-- | sg_unaligned.h | 489 |
1 files changed, 489 insertions, 0 deletions
diff --git a/sg_unaligned.h b/sg_unaligned.h new file mode 100644 index 0000000..ca702e8 --- /dev/null +++ b/sg_unaligned.h @@ -0,0 +1,489 @@ +#ifndef SG_UNALIGNED_H +#define SG_UNALIGNED_H + +/* + * Copyright (c) 2014-2018 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 <stdbool.h> +#include <stdint.h> /* for uint8_t and friends */ +#include <string.h> /* for memcpy */ + +#ifdef __cplusplus +extern "C" { +#endif + +/* These inline functions convert integers (always unsigned) to byte streams + * and vice versa. They have two goals: + * - change the byte ordering of integers between host order and big + * endian ("_be") or little endian ("_le") + * - copy the big or little endian byte stream so it complies with any + * alignment that host integers require + * + * Host integer to given endian byte stream is a "_put_" function taking + * two arguments (integer and pointer to byte stream) returning void. + * Given endian byte stream to host integer is a "_get_" function that takes + * one argument and returns an integer of appropriate size (uint32_t for 24 + * bit operations, uint64_t for 48 bit operations). + * + * 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. + * Little endian is used by ATA, PCI and NVMe. + */ + +/* The generic form of these routines was borrowed from the Linux kernel, + * via mhvtl. There is a specialised version of the main functions for + * little endian or big endian provided that not-quite-standard defines for + * endianness are available from the compiler and the <byteswap.h> header + * (a GNU extension) has been detected by ./configure . To force the + * generic version, use './configure --disable-fast-lebe ' . */ + +/* Note: Assumes that the source and destination locations do not overlap. + * An example of overlapping source and destination: + * sg_put_unaligned_le64(j, ((uint8_t *)&j) + 1); + * Best not to do things like that. + */ + + +#ifdef HAVE_CONFIG_H +#include "config.h" /* need this to see if HAVE_BYTESWAP_H */ +#endif + +#undef GOT_UNALIGNED_SPECIALS /* just in case */ + +#if defined(__BYTE_ORDER__) && defined(HAVE_BYTESWAP_H) && \ + ! defined(IGNORE_FAST_LEBE) + +#if defined(__LITTLE_ENDIAN__) || (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) + +#define GOT_UNALIGNED_SPECIALS 1 + +#include <byteswap.h> /* for bswap_16(), bswap_32() and bswap_64() */ + +// #warning ">>>>>> Doing Little endian special unaligneds" + +static inline uint16_t sg_get_unaligned_be16(const void *p) +{ + uint16_t u; + + memcpy(&u, p, 2); + return bswap_16(u); +} + +static inline uint32_t sg_get_unaligned_be32(const void *p) +{ + uint32_t u; + + memcpy(&u, p, 4); + return bswap_32(u); +} + +static inline uint64_t sg_get_unaligned_be64(const void *p) +{ + uint64_t u; + + memcpy(&u, p, 8); + return bswap_64(u); +} + +static inline void sg_put_unaligned_be16(uint16_t val, void *p) +{ + uint16_t u = bswap_16(val); + + memcpy(p, &u, 2); +} + +static inline void sg_put_unaligned_be32(uint32_t val, void *p) +{ + uint32_t u = bswap_32(val); + + memcpy(p, &u, 4); +} + +static inline void sg_put_unaligned_be64(uint64_t val, void *p) +{ + uint64_t u = bswap_64(val); + + memcpy(p, &u, 8); +} + +static inline uint16_t sg_get_unaligned_le16(const void *p) +{ + uint16_t u; + + memcpy(&u, p, 2); + return u; +} + +static inline uint32_t sg_get_unaligned_le32(const void *p) +{ + uint32_t u; + + memcpy(&u, p, 4); + return u; +} + +static inline uint64_t sg_get_unaligned_le64(const void *p) +{ + uint64_t u; + + memcpy(&u, p, 8); + return u; +} + +static inline void sg_put_unaligned_le16(uint16_t val, void *p) +{ + memcpy(p, &val, 2); +} + +static inline void sg_put_unaligned_le32(uint32_t val, void *p) +{ + memcpy(p, &val, 4); +} + +static inline void sg_put_unaligned_le64(uint64_t val, void *p) +{ + memcpy(p, &val, 8); +} + +#elif defined(__BIG_ENDIAN__) || (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__) + +#define GOT_UNALIGNED_SPECIALS 1 + +#include <byteswap.h> + +// #warning ">>>>>> Doing BIG endian special unaligneds" + +static inline uint16_t sg_get_unaligned_le16(const void *p) +{ + uint16_t u; + + memcpy(&u, p, 2); + return bswap_16(u); +} + +static inline uint32_t sg_get_unaligned_le32(const void *p) +{ + uint32_t u; + + memcpy(&u, p, 4); + return bswap_32(u); +} + +static inline uint64_t sg_get_unaligned_le64(const void *p) +{ + uint64_t u; + + memcpy(&u, p, 8); + return bswap_64(u); +} + +static inline void sg_put_unaligned_le16(uint16_t val, void *p) +{ + uint16_t u = bswap_16(val); + + memcpy(p, &u, 2); +} + +static inline void sg_put_unaligned_le32(uint32_t val, void *p) +{ + uint32_t u = bswap_32(val); + + memcpy(p, &u, 4); +} + +static inline void sg_put_unaligned_le64(uint64_t val, void *p) +{ + uint64_t u = bswap_64(val); + + memcpy(p, &u, 8); +} + +static inline uint16_t sg_get_unaligned_be16(const void *p) +{ + uint16_t u; + + memcpy(&u, p, 2); + return u; +} + +static inline uint32_t sg_get_unaligned_be32(const void *p) +{ + uint32_t u; + + memcpy(&u, p, 4); + return u; +} + +static inline uint64_t sg_get_unaligned_be64(const void *p) +{ + uint64_t u; + + memcpy(&u, p, 8); + return u; +} + +static inline void sg_put_unaligned_be16(uint16_t val, void *p) +{ + memcpy(p, &val, 2); +} + +static inline void sg_put_unaligned_be32(uint32_t val, void *p) +{ + memcpy(p, &val, 4); +} + +static inline void sg_put_unaligned_be64(uint64_t val, void *p) +{ + memcpy(p, &val, 8); +} + +#endif /* __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ */ +#endif /* #if defined __BYTE_ORDER__ && defined <byteswap.h> && + * ! defined IGNORE_FAST_LEBE */ + + +#ifndef GOT_UNALIGNED_SPECIALS + +/* Now we have no tricks left, so use the only way this can be done + * correctly in C safely: lots of shifts. */ + +// #warning ">>>>>> Doing GENERIC unaligneds" + +static inline uint16_t sg_get_unaligned_be16(const void *p) +{ + return ((const uint8_t *)p)[0] << 8 | ((const uint8_t *)p)[1]; +} + +static inline uint32_t sg_get_unaligned_be32(const void *p) +{ + return ((const uint8_t *)p)[0] << 24 | ((const uint8_t *)p)[1] << 16 | + ((const uint8_t *)p)[2] << 8 | ((const uint8_t *)p)[3]; +} + +static inline uint64_t sg_get_unaligned_be64(const void *p) +{ + return (uint64_t)sg_get_unaligned_be32(p) << 32 | + sg_get_unaligned_be32((const uint8_t *)p + 4); +} + +static inline void sg_put_unaligned_be16(uint16_t val, void *p) +{ + ((uint8_t *)p)[0] = (uint8_t)(val >> 8); + ((uint8_t *)p)[1] = (uint8_t)val; +} + +static inline void sg_put_unaligned_be32(uint32_t val, void *p) +{ + sg_put_unaligned_be16(val >> 16, p); + sg_put_unaligned_be16(val, (uint8_t *)p + 2); +} + +static inline void sg_put_unaligned_be64(uint64_t val, void *p) +{ + sg_put_unaligned_be32(val >> 32, p); + sg_put_unaligned_be32(val, (uint8_t *)p + 4); +} + + +static inline uint16_t sg_get_unaligned_le16(const void *p) +{ + return ((const uint8_t *)p)[1] << 8 | ((const uint8_t *)p)[0]; +} + +static inline uint32_t sg_get_unaligned_le32(const void *p) +{ + return ((const uint8_t *)p)[3] << 24 | ((const uint8_t *)p)[2] << 16 | + ((const uint8_t *)p)[1] << 8 | ((const uint8_t *)p)[0]; +} + +static inline uint64_t sg_get_unaligned_le64(const void *p) +{ + return (uint64_t)sg_get_unaligned_le32((const uint8_t *)p + 4) << 32 | + sg_get_unaligned_le32(p); +} + +static inline void sg_put_unaligned_le16(uint16_t val, void *p) +{ + ((uint8_t *)p)[0] = val & 0xff; + ((uint8_t *)p)[1] = val >> 8; +} + +static inline void sg_put_unaligned_le32(uint32_t val, void *p) +{ + sg_put_unaligned_le16(val >> 16, (uint8_t *)p + 2); + sg_put_unaligned_le16(val, p); +} + +static inline void sg_put_unaligned_le64(uint64_t val, void *p) +{ + sg_put_unaligned_le32(val >> 32, (uint8_t *)p + 4); + sg_put_unaligned_le32(val, p); +} + +#endif /* #ifndef GOT_UNALIGNED_SPECIALS */ + +/* Following are lesser used conversions that don't have specializations + * for endianness; big endian first. In summary these are the 24, 48 bit and + * given-length conversions plus the "nz" conditional put conversions. */ + +/* Now big endian, get 24+48 then put 24+48 */ +static inline uint32_t sg_get_unaligned_be24(const void *p) +{ + return ((const uint8_t *)p)[0] << 16 | ((const uint8_t *)p)[1] << 8 | + ((const uint8_t *)p)[2]; +} + +/* Assume 48 bit value placed in uint64_t */ +static inline uint64_t sg_get_unaligned_be48(const void *p) +{ + return (uint64_t)sg_get_unaligned_be16(p) << 32 | + sg_get_unaligned_be32((const uint8_t *)p + 2); +} + +/* 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 byte 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_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; +} + +/* Assume 48 bit value placed in uint64_t */ +static inline void sg_put_unaligned_be48(uint64_t val, void *p) +{ + sg_put_unaligned_be16(val >> 32, p); + sg_put_unaligned_be32(val, (uint8_t *)p + 2); +} + +/* Now little endian, get 24+48 then put 24+48 */ +static inline uint32_t sg_get_unaligned_le24(const void *p) +{ + return (uint32_t)sg_get_unaligned_le16(p) | + ((const uint8_t *)p)[2] << 16; +} + +/* Assume 48 bit value placed in uint64_t */ +static inline uint64_t sg_get_unaligned_le48(const void *p) +{ + return (uint64_t)sg_get_unaligned_le16((const uint8_t *)p + 4) << 32 | + sg_get_unaligned_le32(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; +} + +/* 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; +} + +/* 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 byte 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; + } +} + +/* 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. First big endian, then little */ +static inline void sg_nz_put_unaligned_be16(uint16_t val, void *p) +{ + if (val) + sg_put_unaligned_be16(val, 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) + sg_put_unaligned_be32(val, p); +} + +static inline void sg_nz_put_unaligned_be64(uint64_t val, void *p) +{ + if (val) + sg_put_unaligned_be64(val, p); +} + +static inline void sg_nz_put_unaligned_le16(uint16_t val, void *p) +{ + if (val) + sg_put_unaligned_le16(val, 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) + sg_put_unaligned_le32(val, p); +} + +static inline void sg_nz_put_unaligned_le64(uint64_t val, void *p) +{ + if (val) + sg_put_unaligned_le64(val, p); +} + + +#ifdef __cplusplus +} +#endif + +#endif /* SG_UNALIGNED_H */ |