Files
thirdparty-littlefs/bd/lfs_rambd.h
Christopher Haster a7cdd563f6 Changed callbacks to take user-provided context directly
This is a style change to make littlefs's callbacks consistent with most
callback declarations found in C. That is, taking in a user-provided
`void*`.

Previously, these callbacks took a pointer to the config struct itself,
which indirectly contained a user provided context, and this gets the
job done, but taking in a callback with a `void*` is arguably more
expected, has a better chance of integrating with C++/OS-specific code,
and is more likely to be optimized out by a clever compiler.

---

As a part of these changes, the geometry for the test bds needed to be
moved into bd specific configuration objects. This is a good change as
it also allows for testing situations where littlefs's geometry does not
match the underlying bd.
2020-11-28 20:02:18 -06:00

87 lines
2.0 KiB
C

/*
* Block device emulated in RAM
*
* Copyright (c) 2017, Arm Limited. All rights reserved.
* SPDX-License-Identifier: BSD-3-Clause
*/
#ifndef LFS_RAMBD_H
#define LFS_RAMBD_H
#include "lfs.h"
#ifdef __cplusplus
extern "C" {
#endif
// Block device specific tracing
#ifdef LFS_RAMBD_YES_TRACE
#define LFS_RAMBD_TRACE(...) LFS_TRACE(__VA_ARGS__)
#else
#define LFS_RAMBD_TRACE(...)
#endif
// rambd config (optional)
struct lfs_rambd_cfg {
// Minimum size of block read. All read operations must be a
// multiple of this value.
lfs_size_t read_size;
// Minimum size of block program. All program operations must be a
// multiple of this value.
lfs_size_t prog_size;
// Size of an erasable block.
lfs_size_t erase_size;
// Number of erasable blocks on the device.
lfs_size_t erase_count;
// 8-bit erase value to simulate erasing with. -1 indicates no erase
// occurs, which is still a valid block device
int32_t erase_value;
// Optional statically allocated buffer for the block device.
void *buffer;
};
// rambd state
typedef struct lfs_rambd {
uint8_t *buffer;
struct lfs_rambd_cfg cfg;
} lfs_rambd_t;
// Create a RAM block device using the geometry in lfs_cfg
int lfs_rambd_createcfg(lfs_rambd_t *bd,
const struct lfs_rambd_cfg *cfg);
// Clean up memory associated with block device
int lfs_rambd_destroy(lfs_rambd_t *bd);
// Read a block
int lfs_rambd_read(lfs_rambd_t *bd, lfs_block_t block,
lfs_off_t off, void *buffer, lfs_size_t size);
// Program a block
//
// The block must have previously been erased.
int lfs_rambd_prog(lfs_rambd_t *bd, lfs_block_t block,
lfs_off_t off, const void *buffer, lfs_size_t size);
// Erase a block
//
// A block must be erased before being programmed. The
// state of an erased block is undefined.
int lfs_rambd_erase(lfs_rambd_t *bd, lfs_block_t block);
// Sync the block device
int lfs_rambd_sync(lfs_rambd_t *bd);
#ifdef __cplusplus
}
#endif
#endif