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1/* SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause */2/*3 * Copyright (c) Yann Collet, Facebook, Inc.4 * All rights reserved.5 *6 * This source code is licensed under both the BSD-style license (found in the7 * LICENSE file in the root directory of this source tree) and the GPLv2 (found8 * in the COPYING file in the root directory of this source tree).9 * You may select, at your option, one of the above-listed licenses.10 */11 12#ifndef MEM_H_MODULE13#define MEM_H_MODULE14 15/*-****************************************16* Dependencies17******************************************/18#include <linux/unaligned.h> /* get_unaligned, put_unaligned* */19#include <linux/compiler.h> /* inline */20#include <linux/swab.h> /* swab32, swab64 */21#include <linux/types.h> /* size_t, ptrdiff_t */22#include "debug.h" /* DEBUG_STATIC_ASSERT */23 24/*-****************************************25* Compiler specifics26******************************************/27#define MEM_STATIC static inline28 29/*-**************************************************************30* Basic Types31*****************************************************************/32typedef uint8_t BYTE;33typedef uint8_t U8;34typedef int8_t S8;35typedef uint16_t U16;36typedef int16_t S16;37typedef uint32_t U32;38typedef int32_t S32;39typedef uint64_t U64;40typedef int64_t S64;41 42/*-**************************************************************43* Memory I/O API44*****************************************************************/45/*=== Static platform detection ===*/46MEM_STATIC unsigned MEM_32bits(void);47MEM_STATIC unsigned MEM_64bits(void);48MEM_STATIC unsigned MEM_isLittleEndian(void);49 50/*=== Native unaligned read/write ===*/51MEM_STATIC U16 MEM_read16(const void* memPtr);52MEM_STATIC U32 MEM_read32(const void* memPtr);53MEM_STATIC U64 MEM_read64(const void* memPtr);54MEM_STATIC size_t MEM_readST(const void* memPtr);55 56MEM_STATIC void MEM_write16(void* memPtr, U16 value);57MEM_STATIC void MEM_write32(void* memPtr, U32 value);58MEM_STATIC void MEM_write64(void* memPtr, U64 value);59 60/*=== Little endian unaligned read/write ===*/61MEM_STATIC U16 MEM_readLE16(const void* memPtr);62MEM_STATIC U32 MEM_readLE24(const void* memPtr);63MEM_STATIC U32 MEM_readLE32(const void* memPtr);64MEM_STATIC U64 MEM_readLE64(const void* memPtr);65MEM_STATIC size_t MEM_readLEST(const void* memPtr);66 67MEM_STATIC void MEM_writeLE16(void* memPtr, U16 val);68MEM_STATIC void MEM_writeLE24(void* memPtr, U32 val);69MEM_STATIC void MEM_writeLE32(void* memPtr, U32 val32);70MEM_STATIC void MEM_writeLE64(void* memPtr, U64 val64);71MEM_STATIC void MEM_writeLEST(void* memPtr, size_t val);72 73/*=== Big endian unaligned read/write ===*/74MEM_STATIC U32 MEM_readBE32(const void* memPtr);75MEM_STATIC U64 MEM_readBE64(const void* memPtr);76MEM_STATIC size_t MEM_readBEST(const void* memPtr);77 78MEM_STATIC void MEM_writeBE32(void* memPtr, U32 val32);79MEM_STATIC void MEM_writeBE64(void* memPtr, U64 val64);80MEM_STATIC void MEM_writeBEST(void* memPtr, size_t val);81 82/*=== Byteswap ===*/83MEM_STATIC U32 MEM_swap32(U32 in);84MEM_STATIC U64 MEM_swap64(U64 in);85MEM_STATIC size_t MEM_swapST(size_t in);86 87/*-**************************************************************88* Memory I/O Implementation89*****************************************************************/90MEM_STATIC unsigned MEM_32bits(void)91{92 return sizeof(size_t) == 4;93}94 95MEM_STATIC unsigned MEM_64bits(void)96{97 return sizeof(size_t) == 8;98}99 100#if defined(__LITTLE_ENDIAN)101#define MEM_LITTLE_ENDIAN 1102#else103#define MEM_LITTLE_ENDIAN 0104#endif105 106MEM_STATIC unsigned MEM_isLittleEndian(void)107{108 return MEM_LITTLE_ENDIAN;109}110 111MEM_STATIC U16 MEM_read16(const void *memPtr)112{113 return get_unaligned((const U16 *)memPtr);114}115 116MEM_STATIC U32 MEM_read32(const void *memPtr)117{118 return get_unaligned((const U32 *)memPtr);119}120 121MEM_STATIC U64 MEM_read64(const void *memPtr)122{123 return get_unaligned((const U64 *)memPtr);124}125 126MEM_STATIC size_t MEM_readST(const void *memPtr)127{128 return get_unaligned((const size_t *)memPtr);129}130 131MEM_STATIC void MEM_write16(void *memPtr, U16 value)132{133 put_unaligned(value, (U16 *)memPtr);134}135 136MEM_STATIC void MEM_write32(void *memPtr, U32 value)137{138 put_unaligned(value, (U32 *)memPtr);139}140 141MEM_STATIC void MEM_write64(void *memPtr, U64 value)142{143 put_unaligned(value, (U64 *)memPtr);144}145 146/*=== Little endian r/w ===*/147 148MEM_STATIC U16 MEM_readLE16(const void *memPtr)149{150 return get_unaligned_le16(memPtr);151}152 153MEM_STATIC void MEM_writeLE16(void *memPtr, U16 val)154{155 put_unaligned_le16(val, memPtr);156}157 158MEM_STATIC U32 MEM_readLE24(const void *memPtr)159{160 return MEM_readLE16(memPtr) + (((const BYTE *)memPtr)[2] << 16);161}162 163MEM_STATIC void MEM_writeLE24(void *memPtr, U32 val)164{165 MEM_writeLE16(memPtr, (U16)val);166 ((BYTE *)memPtr)[2] = (BYTE)(val >> 16);167}168 169MEM_STATIC U32 MEM_readLE32(const void *memPtr)170{171 return get_unaligned_le32(memPtr);172}173 174MEM_STATIC void MEM_writeLE32(void *memPtr, U32 val32)175{176 put_unaligned_le32(val32, memPtr);177}178 179MEM_STATIC U64 MEM_readLE64(const void *memPtr)180{181 return get_unaligned_le64(memPtr);182}183 184MEM_STATIC void MEM_writeLE64(void *memPtr, U64 val64)185{186 put_unaligned_le64(val64, memPtr);187}188 189MEM_STATIC size_t MEM_readLEST(const void *memPtr)190{191 if (MEM_32bits())192 return (size_t)MEM_readLE32(memPtr);193 else194 return (size_t)MEM_readLE64(memPtr);195}196 197MEM_STATIC void MEM_writeLEST(void *memPtr, size_t val)198{199 if (MEM_32bits())200 MEM_writeLE32(memPtr, (U32)val);201 else202 MEM_writeLE64(memPtr, (U64)val);203}204 205/*=== Big endian r/w ===*/206 207MEM_STATIC U32 MEM_readBE32(const void *memPtr)208{209 return get_unaligned_be32(memPtr);210}211 212MEM_STATIC void MEM_writeBE32(void *memPtr, U32 val32)213{214 put_unaligned_be32(val32, memPtr);215}216 217MEM_STATIC U64 MEM_readBE64(const void *memPtr)218{219 return get_unaligned_be64(memPtr);220}221 222MEM_STATIC void MEM_writeBE64(void *memPtr, U64 val64)223{224 put_unaligned_be64(val64, memPtr);225}226 227MEM_STATIC size_t MEM_readBEST(const void *memPtr)228{229 if (MEM_32bits())230 return (size_t)MEM_readBE32(memPtr);231 else232 return (size_t)MEM_readBE64(memPtr);233}234 235MEM_STATIC void MEM_writeBEST(void *memPtr, size_t val)236{237 if (MEM_32bits())238 MEM_writeBE32(memPtr, (U32)val);239 else240 MEM_writeBE64(memPtr, (U64)val);241}242 243MEM_STATIC U32 MEM_swap32(U32 in)244{245 return swab32(in);246}247 248MEM_STATIC U64 MEM_swap64(U64 in)249{250 return swab64(in);251}252 253MEM_STATIC size_t MEM_swapST(size_t in)254{255 if (MEM_32bits())256 return (size_t)MEM_swap32((U32)in);257 else258 return (size_t)MEM_swap64((U64)in);259}260 261#endif /* MEM_H_MODULE */262