diff options
Diffstat (limited to 'lib/zstd/mem.h')
| -rw-r--r-- | lib/zstd/mem.h | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/lib/zstd/mem.h b/lib/zstd/mem.h new file mode 100644 index 0000000000..3a0f34c870 --- /dev/null +++ b/lib/zstd/mem.h @@ -0,0 +1,151 @@ +/** + * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of https://github.com/facebook/zstd. + * An additional grant of patent rights can be found in the PATENTS file in the + * same directory. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + */ + +#ifndef MEM_H_MODULE +#define MEM_H_MODULE + +/*-**************************************** +* Dependencies +******************************************/ +#include <asm/unaligned.h> +#include <linux/string.h> /* memcpy */ +#include <linux/types.h> /* size_t, ptrdiff_t */ + +/*-**************************************** +* Compiler specifics +******************************************/ +#define ZSTD_STATIC static __inline __attribute__((unused)) + +/*-************************************************************** +* Basic Types +*****************************************************************/ +typedef uint8_t BYTE; +typedef uint16_t U16; +typedef int16_t S16; +typedef uint32_t U32; +typedef int32_t S32; +typedef uint64_t U64; +typedef int64_t S64; +typedef ptrdiff_t iPtrDiff; +typedef uintptr_t uPtrDiff; + +/*-************************************************************** +* Memory I/O +*****************************************************************/ +ZSTD_STATIC unsigned ZSTD_32bits(void) { return sizeof(size_t) == 4; } +ZSTD_STATIC unsigned ZSTD_64bits(void) { return sizeof(size_t) == 8; } + +#if defined(__LITTLE_ENDIAN) +#define ZSTD_LITTLE_ENDIAN 1 +#else +#define ZSTD_LITTLE_ENDIAN 0 +#endif + +ZSTD_STATIC unsigned ZSTD_isLittleEndian(void) { return ZSTD_LITTLE_ENDIAN; } + +ZSTD_STATIC U16 ZSTD_read16(const void *memPtr) { return get_unaligned((const U16 *)memPtr); } + +ZSTD_STATIC U32 ZSTD_read32(const void *memPtr) { return get_unaligned((const U32 *)memPtr); } + +ZSTD_STATIC U64 ZSTD_read64(const void *memPtr) { return get_unaligned((const U64 *)memPtr); } + +ZSTD_STATIC size_t ZSTD_readST(const void *memPtr) { return get_unaligned((const size_t *)memPtr); } + +ZSTD_STATIC void ZSTD_write16(void *memPtr, U16 value) { put_unaligned(value, (U16 *)memPtr); } + +ZSTD_STATIC void ZSTD_write32(void *memPtr, U32 value) { put_unaligned(value, (U32 *)memPtr); } + +ZSTD_STATIC void ZSTD_write64(void *memPtr, U64 value) { put_unaligned(value, (U64 *)memPtr); } + +/*=== Little endian r/w ===*/ + +ZSTD_STATIC U16 ZSTD_readLE16(const void *memPtr) { return get_unaligned_le16(memPtr); } + +ZSTD_STATIC void ZSTD_writeLE16(void *memPtr, U16 val) { put_unaligned_le16(val, memPtr); } + +ZSTD_STATIC U32 ZSTD_readLE24(const void *memPtr) { return ZSTD_readLE16(memPtr) + (((const BYTE *)memPtr)[2] << 16); } + +ZSTD_STATIC void ZSTD_writeLE24(void *memPtr, U32 val) +{ + ZSTD_writeLE16(memPtr, (U16)val); + ((BYTE *)memPtr)[2] = (BYTE)(val >> 16); +} + +ZSTD_STATIC U32 ZSTD_readLE32(const void *memPtr) { return get_unaligned_le32(memPtr); } + +ZSTD_STATIC void ZSTD_writeLE32(void *memPtr, U32 val32) { put_unaligned_le32(val32, memPtr); } + +ZSTD_STATIC U64 ZSTD_readLE64(const void *memPtr) { return get_unaligned_le64(memPtr); } + +ZSTD_STATIC void ZSTD_writeLE64(void *memPtr, U64 val64) { put_unaligned_le64(val64, memPtr); } + +ZSTD_STATIC size_t ZSTD_readLEST(const void *memPtr) +{ + if (ZSTD_32bits()) + return (size_t)ZSTD_readLE32(memPtr); + else + return (size_t)ZSTD_readLE64(memPtr); +} + +ZSTD_STATIC void ZSTD_writeLEST(void *memPtr, size_t val) +{ + if (ZSTD_32bits()) + ZSTD_writeLE32(memPtr, (U32)val); + else + ZSTD_writeLE64(memPtr, (U64)val); +} + +/*=== Big endian r/w ===*/ + +ZSTD_STATIC U32 ZSTD_readBE32(const void *memPtr) { return get_unaligned_be32(memPtr); } + +ZSTD_STATIC void ZSTD_writeBE32(void *memPtr, U32 val32) { put_unaligned_be32(val32, memPtr); } + +ZSTD_STATIC U64 ZSTD_readBE64(const void *memPtr) { return get_unaligned_be64(memPtr); } + +ZSTD_STATIC void ZSTD_writeBE64(void *memPtr, U64 val64) { put_unaligned_be64(val64, memPtr); } + +ZSTD_STATIC size_t ZSTD_readBEST(const void *memPtr) +{ + if (ZSTD_32bits()) + return (size_t)ZSTD_readBE32(memPtr); + else + return (size_t)ZSTD_readBE64(memPtr); +} + +ZSTD_STATIC void ZSTD_writeBEST(void *memPtr, size_t val) +{ + if (ZSTD_32bits()) + ZSTD_writeBE32(memPtr, (U32)val); + else + ZSTD_writeBE64(memPtr, (U64)val); +} + +/* function safe only for comparisons */ +ZSTD_STATIC U32 ZSTD_readMINMATCH(const void *memPtr, U32 length) +{ + switch (length) { + default: + case 4: return ZSTD_read32(memPtr); + case 3: + if (ZSTD_isLittleEndian()) + return ZSTD_read32(memPtr) << 8; + else + return ZSTD_read32(memPtr) >> 8; + } +} + +#endif /* MEM_H_MODULE */ |