About RamFS

RamFS is a memory based filesystem designed for embedded use. It can be easily used with a CMake project — including ESP-IDF.

Getting started with ESP-IDF

To use this component with ESP-IDF, within your projects directory run

idf.py add-dependency jkent/ramfs

Usage

Two interfaces are available: the bare API or when using IDF there is the VFS interface which builds on top of the bare API. You should use the VFS interface in IDF projects, as it uses the portable and familiar posix and stdio C functions with it. There is nothing preventing you from mix and matching both at the same time, however.

Shared initialization

Initialization is as simple as calling ramfs_init function and checking its return variable:

ramfs_fs_t *fs = ramfs_init();
assert(fs != NULL);

When done, and all file handles are closed, you can call ramfs_deinit:

ramfs_deinit(fs);

VFS interface

The VFS interface adds another step to the initialization: you define a ramfs_vfs_conf_t structure:

base_path - path to mount the ramfs
fs - a ramfs_fs_t instance
max_files - max number of files that can be open at a time

ramfs_vfs_conf_t ramfs_vfs_conf = {
    .base_path = "/ramfs",
    .fs = fs,
    .max_files = 5,
};
ramfs_vfs_register(&ramfs_vfs_conf);

Bare API

Filesystem functions:

ramfs_fs_t *ramfs_init(void)
void ramfs_deinit(ramfs_fs_t *fs)

Object functions:

const ramfs_entry_t ramfs_get_parent(ramfs_fs_t fs, const char *path)
const ramfs_entry_t ramfs_get_entry(ramfs_fs_t fs, const char *path)
const char ramfs_get_name(const ramfs_entry_t entry)
const char ramfs_get_path(const ramfs_entry_t entry)
int ramfs_is_dir(const ramfs_entry_t *entry)
int ramfs_is_file(const ramfs_entry_t *entry)
void ramfs_stat(const ramfs_fs_t fs, const ramfs_entry_t entry, ramfs_stat_t *st)
void ramfs_create(ramfs_fs_t fs, const char path, int flags)
void ramfs_truncate(ramfs_fs_t fs, const ramfs_entry_t entry, size_T size)
ramfs_fh_t ramfs_open(ramfs_fs_t fs, const ramfs_entry_t *entry, unsigned int flags)
void ramfs_close(ramfs_fh_t *fh)
size_t ramfs_read(ramfs_fh_t fh, void buf, size_t len)
size_t ramfs_write(ramfs_fh_t fh, void buf, size_t len)
ssize_t ramfs_seek(ramfs_fh_t *fh, long offset, int mode)
size_t ramfs_tell(ramfs_fh_t *fh)
size_t ramfs_access(ramfs_fh_t *fh, void **buf)
int ramfs_unlink(ramfs_entry_t *entry)
int ramfs_rename(ramfs_fs_t fs, const char src, const char *dst)

Directory Functions:

ramfs_dh_t ramfs_opendir(ramfs_fs_t fs, const ramfs_entry_t *entry)
void ramfs_closedir(ramfs_dh_t *dh)
const ramfs_entry_t ramfs_readdir(ramfs_dh_t dh)
void ramfs_seekdir(ramfs_dh_t *dh, long loc)
long ramfs_telldir(ramfs_dh_t *dh)
ramfs_entry_t ramfs_mkdir(ramfs_fs_t fs, const char *name)
int ramfs_rmdir(ramfs_entry_t *entry)
void ramfs_rmtree(ramfs_entry_t *entry)

jkent / ramfs

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