Files
thirdparty-littlefs/lfs_util.h
Christopher Haster f3e4f78fe4 A number of small QOL changes related to lfs_util.h
- Removed stdlib includes from lfs.h, these should all go through
  lfs_util.h to let users override these definitions if stdlib is
  unavailable on their system.

- Changed the name of the LFS_CONFIG macro to LFS_UTIL to avoid
  confusion with the lfs_config struct. This also hints that LFS_UTIL
  is related to lfs_util.h.

  LFS_UTIL allows the user to override lfs_util.h so they can provide
  their own system-level dependencies such as malloc, tracing, builtins,
  stdint definitions, string.h, and others.

- Moved error code definitions to lfs_util.h. This lets users override
  the error codes to replace them with their own error codes and avoid
  a translation layer in some situations. Note the error codes must
  still be in the range of a negative int.
2019-11-30 14:40:05 -06:00

254 lines
7.7 KiB
C

/*
* lfs utility functions
*
* Copyright (c) 2017, Arm Limited. All rights reserved.
* SPDX-License-Identifier: BSD-3-Clause
*
* Can be overridden by users with their own configuration by defining
* LFS_UTIL as a header file (-DLFS_UTIL=my_lfs_util.h)
*
* If LFS_UTIL is defined, none of the default definitions will be
* emitted and must be provided by the user's header file. To start, I would
* suggest copying lfs_util.h and modifying as needed.
*/
#ifndef LFS_UTIL_H
#define LFS_UTIL_H
#ifdef LFS_UTIL
#define LFS_STRINGIZE(x) LFS_STRINGIZE2(x)
#define LFS_STRINGIZE2(x) #x
#include LFS_STRINGIZE(LFS_UTIL)
#else
// System includes
#include <stdint.h>
#include <stdbool.h>
#include <string.h>
#include <inttypes.h>
#ifndef LFS_NO_MALLOC
#include <stdlib.h>
#endif
#ifndef LFS_NO_ASSERT
#include <assert.h>
#endif
#if !defined(LFS_NO_DEBUG) || \
!defined(LFS_NO_WARN) || \
!defined(LFS_NO_ERROR) || \
defined(LFS_YES_TRACE)
#include <stdio.h>
#endif
#ifdef __cplusplus
extern "C"
{
#endif
// Possible error codes, these are negative to allow valid positive
// return values. May be redefined to system error codes as long as
// they are negative.
enum lfs_error {
LFS_ERR_OK = 0, // No error
LFS_ERR_IO = -5, // Error during device operation
LFS_ERR_CORRUPT = -84, // Corrupted
LFS_ERR_NOENT = -2, // No directory entry
LFS_ERR_EXIST = -17, // Entry already exists
LFS_ERR_NOTDIR = -20, // Entry is not a dir
LFS_ERR_ISDIR = -21, // Entry is a dir
LFS_ERR_NOTEMPTY = -39, // Dir is not empty
LFS_ERR_BADF = -9, // Bad file number
LFS_ERR_FBIG = -27, // File too large
LFS_ERR_INVAL = -22, // Invalid parameter
LFS_ERR_NOSPC = -28, // No space left on device
LFS_ERR_NOMEM = -12, // No more memory available
LFS_ERR_NOATTR = -61, // No data/attr available
LFS_ERR_NAMETOOLONG = -36, // File name too long
};
// Macros, may be replaced by system specific wrappers. Arguments to these
// macros must not have side-effects as the macros can be removed for a smaller
// code footprint
// Logging functions
#ifdef LFS_YES_TRACE
#define LFS_TRACE(fmt, ...) \
printf("lfs_trace:%d: " fmt "\n", __LINE__, __VA_ARGS__)
#else
#define LFS_TRACE(fmt, ...)
#endif
#ifndef LFS_NO_DEBUG
#define LFS_DEBUG(fmt, ...) \
printf("lfs_debug:%d: " fmt "\n", __LINE__, __VA_ARGS__)
#else
#define LFS_DEBUG(fmt, ...)
#endif
#ifndef LFS_NO_WARN
#define LFS_WARN(fmt, ...) \
printf("lfs_warn:%d: " fmt "\n", __LINE__, __VA_ARGS__)
#else
#define LFS_WARN(fmt, ...)
#endif
#ifndef LFS_NO_ERROR
#define LFS_ERROR(fmt, ...) \
printf("lfs_error:%d: " fmt "\n", __LINE__, __VA_ARGS__)
#else
#define LFS_ERROR(fmt, ...)
#endif
// Runtime assertions
#ifndef LFS_NO_ASSERT
#define LFS_ASSERT(test) assert(test)
#else
#define LFS_ASSERT(test)
#endif
// Builtin functions, these may be replaced by more efficient
// toolchain-specific implementations. LFS_NO_INTRINSICS falls back to a more
// expensive basic C implementation for debugging purposes
// Min/max functions for unsigned 32-bit numbers
static inline uint32_t lfs_max(uint32_t a, uint32_t b) {
return (a > b) ? a : b;
}
static inline uint32_t lfs_min(uint32_t a, uint32_t b) {
return (a < b) ? a : b;
}
// Align to nearest multiple of a size
static inline uint32_t lfs_aligndown(uint32_t a, uint32_t alignment) {
return a - (a % alignment);
}
static inline uint32_t lfs_alignup(uint32_t a, uint32_t alignment) {
return lfs_aligndown(a + alignment-1, alignment);
}
// Find the next smallest power of 2 less than or equal to a
static inline uint32_t lfs_npw2(uint32_t a) {
#if !defined(LFS_NO_INTRINSICS) && (defined(__GNUC__) || defined(__CC_ARM))
return 32 - __builtin_clz(a-1);
#else
uint32_t r = 0;
uint32_t s;
a -= 1;
s = (a > 0xffff) << 4; a >>= s; r |= s;
s = (a > 0xff ) << 3; a >>= s; r |= s;
s = (a > 0xf ) << 2; a >>= s; r |= s;
s = (a > 0x3 ) << 1; a >>= s; r |= s;
return (r | (a >> 1)) + 1;
#endif
}
// Count the number of trailing binary zeros in a
// lfs_ctz(0) may be undefined
static inline uint32_t lfs_ctz(uint32_t a) {
#if !defined(LFS_NO_INTRINSICS) && defined(__GNUC__)
return __builtin_ctz(a);
#else
return lfs_npw2((a & -a) + 1) - 1;
#endif
}
// Count the number of binary ones in a
static inline uint32_t lfs_popc(uint32_t a) {
#if !defined(LFS_NO_INTRINSICS) && (defined(__GNUC__) || defined(__CC_ARM))
return __builtin_popcount(a);
#else
a = a - ((a >> 1) & 0x55555555);
a = (a & 0x33333333) + ((a >> 2) & 0x33333333);
return (((a + (a >> 4)) & 0xf0f0f0f) * 0x1010101) >> 24;
#endif
}
// Find the sequence comparison of a and b, this is the distance
// between a and b ignoring overflow
static inline int32_t lfs_scmp(uint32_t a, uint32_t b) {
return (int32_t)(uint32_t)(a - b);
}
// Convert between 32-bit little-endian and native order
static inline uint32_t lfs_fromle32(uint32_t a) {
#if !defined(LFS_NO_INTRINSICS) && ( \
(defined( BYTE_ORDER ) && defined( ORDER_LITTLE_ENDIAN ) && BYTE_ORDER == ORDER_LITTLE_ENDIAN ) || \
(defined(__BYTE_ORDER ) && defined(__ORDER_LITTLE_ENDIAN ) && __BYTE_ORDER == __ORDER_LITTLE_ENDIAN ) || \
(defined(__BYTE_ORDER__) && defined(__ORDER_LITTLE_ENDIAN__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__))
return a;
#elif !defined(LFS_NO_INTRINSICS) && ( \
(defined( BYTE_ORDER ) && defined( ORDER_BIG_ENDIAN ) && BYTE_ORDER == ORDER_BIG_ENDIAN ) || \
(defined(__BYTE_ORDER ) && defined(__ORDER_BIG_ENDIAN ) && __BYTE_ORDER == __ORDER_BIG_ENDIAN ) || \
(defined(__BYTE_ORDER__) && defined(__ORDER_BIG_ENDIAN__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__))
return __builtin_bswap32(a);
#else
return (((uint8_t*)&a)[0] << 0) |
(((uint8_t*)&a)[1] << 8) |
(((uint8_t*)&a)[2] << 16) |
(((uint8_t*)&a)[3] << 24);
#endif
}
static inline uint32_t lfs_tole32(uint32_t a) {
return lfs_fromle32(a);
}
// Convert between 32-bit big-endian and native order
static inline uint32_t lfs_frombe32(uint32_t a) {
#if !defined(LFS_NO_INTRINSICS) && ( \
(defined( BYTE_ORDER ) && defined( ORDER_LITTLE_ENDIAN ) && BYTE_ORDER == ORDER_LITTLE_ENDIAN ) || \
(defined(__BYTE_ORDER ) && defined(__ORDER_LITTLE_ENDIAN ) && __BYTE_ORDER == __ORDER_LITTLE_ENDIAN ) || \
(defined(__BYTE_ORDER__) && defined(__ORDER_LITTLE_ENDIAN__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__))
return __builtin_bswap32(a);
#elif !defined(LFS_NO_INTRINSICS) && ( \
(defined( BYTE_ORDER ) && defined( ORDER_BIG_ENDIAN ) && BYTE_ORDER == ORDER_BIG_ENDIAN ) || \
(defined(__BYTE_ORDER ) && defined(__ORDER_BIG_ENDIAN ) && __BYTE_ORDER == __ORDER_BIG_ENDIAN ) || \
(defined(__BYTE_ORDER__) && defined(__ORDER_BIG_ENDIAN__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__))
return a;
#else
return (((uint8_t*)&a)[0] << 24) |
(((uint8_t*)&a)[1] << 16) |
(((uint8_t*)&a)[2] << 8) |
(((uint8_t*)&a)[3] << 0);
#endif
}
static inline uint32_t lfs_tobe32(uint32_t a) {
return lfs_frombe32(a);
}
// Calculate CRC-32 with polynomial = 0x04c11db7
uint32_t lfs_crc(uint32_t crc, const void *buffer, size_t size);
// Allocate memory, only used if buffers are not provided to littlefs
// Note, memory must be 64-bit aligned
static inline void *lfs_malloc(size_t size) {
#ifndef LFS_NO_MALLOC
return malloc(size);
#else
(void)size;
return NULL;
#endif
}
// Deallocate memory, only used if buffers are not provided to littlefs
static inline void lfs_free(void *p) {
#ifndef LFS_NO_MALLOC
free(p);
#else
(void)p;
#endif
}
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif
#endif