// This file is part of the CircuitPython project: https://circuitpython.org

//

// SPDX-FileCopyrightText: Copyright (c) 2017 Scott Shawcroft for Adafruit Industries

//

// SPDX-License-Identifier: MIT

#include "supervisor/filesystem.h"

#include "extmod/vfs_fat.h"

#include "lib/oofatfs/ff.h"

#include "lib/oofatfs/diskio.h"

#include "py/mpstate.h"

#include "supervisor/flash.h"

#include "supervisor/linker.h"

#if CIRCUITPY_SDCARDIO

#include "shared-module/sdcardio/__init__.h"

#endif

static mp_vfs_mount_t _circuitpy_vfs;

static fs_user_mount_t _circuitpy_usermount;

#if CIRCUITPY_SAVES_PARTITION_SIZE > 0

static mp_vfs_mount_t _saves_vfs;

static fs_user_mount_t _saves_usermount;

#endif

static volatile uint32_t filesystem_flush_interval_ms = CIRCUITPY_FILESYSTEM_FLUSH_INTERVAL_MS;

volatile bool filesystem_flush_requested = false;

void filesystem_background(void) {

if (filesystem_flush_requested) {

filesystem_flush_interval_ms = CIRCUITPY_FILESYSTEM_FLUSH_INTERVAL_MS;

// Flush but keep caches

supervisor_flash_flush();

filesystem_flush_requested = false;

}

}

inline void filesystem_tick(void) {

if (filesystem_flush_interval_ms == 0) {

// 0 means not turned on.

return;

}

if (filesystem_flush_interval_ms == 1) {

filesystem_flush_requested = true;

filesystem_flush_interval_ms = CIRCUITPY_FILESYSTEM_FLUSH_INTERVAL_MS;

} else {

filesystem_flush_interval_ms--;

}

}

__attribute__((unused)) // this function MAY be unused

static void make_empty_file(FATFS *fatfs, const char *path) {

FIL fp;

f_open(fatfs, &fp, path, FA_WRITE | FA_CREATE_ALWAYS);

f_close(&fp);

}

#if CIRCUITPY_FULL_BUILD

#define MAKE_FILE_WITH_OPTIONAL_CONTENTS(fatfs, filename, string_literal) do { \

const byte buffer[] = string_literal; \

make_file_with_contents(fatfs, filename, buffer, sizeof(buffer) - 1); \

} while (0)

static void make_file_with_contents(FATFS *fatfs, const char *filename, const byte *content, UINT size) {

FIL fs;

// Create or modify existing code.py file

f_open(fatfs, &fs, filename, FA_WRITE | FA_CREATE_ALWAYS);

f_write(&fs, content, size, &size);

f_close(&fs);

}

#else

#define MAKE_FILE_WITH_OPTIONAL_CONTENTS(fatfs, filename, string_literal) \

make_empty_file(fatfs, filename)

#endif

// we don't make this function static because it needs a lot of stack and we

// want it to be executed without using stack within main() function

bool filesystem_init(bool create_allowed, bool force_create) {

// init the vfs object

fs_user_mount_t *circuitpy = &_circuitpy_usermount;

circuitpy->blockdev.flags = 0;

supervisor_flash_init_vfs(circuitpy);

#if CIRCUITPY_SAVES_PARTITION_SIZE > 0

// SAVES is placed before CIRCUITPY so that CIRCUITPY takes up the remaining space.

circuitpy->blockdev.offset = CIRCUITPY_SAVES_PARTITION_SIZE;

circuitpy->blockdev.size = -1;

fs_user_mount_t *saves = &_saves_usermount;

saves->blockdev.flags = 0;

saves->blockdev.offset = 0;

saves->blockdev.size = CIRCUITPY_SAVES_PARTITION_SIZE;

supervisor_flash_init_vfs(saves);

filesystem_set_concurrent_write_protection(saves, true);

filesystem_set_writable_by_usb(saves, false);

#endif

mp_vfs_mount_t *circuitpy_vfs = &_circuitpy_vfs;

circuitpy_vfs->len = 0;

// try to mount the flash

FRESULT res = f_mount(&circuitpy->fatfs);

if ((res == FR_NO_FILESYSTEM && create_allowed) || force_create) {

// No filesystem so create a fresh one, or reformat has been requested.

uint8_t working_buf[FF_MAX_SS];

BYTE formats = FM_FAT;

#if FF_FS_EXFAT

formats |= FM_EXFAT | FM_FAT32;

#endif

res = f_mkfs(&circuitpy->fatfs, formats, 0, working_buf, sizeof(working_buf));

if (res != FR_OK) {

return false;

}

// Flush the new file system to make sure it's repaired immediately.

supervisor_flash_flush();

// set label

#ifdef CIRCUITPY_DRIVE_LABEL

res = f_setlabel(&circuitpy->fatfs, CIRCUITPY_DRIVE_LABEL);

#else

res = f_setlabel(&circuitpy->fatfs, "CIRCUITPY");

#endif

if (res != FR_OK) {

return false;

}

#if CIRCUITPY_USB_DEVICE

// inhibit file indexing on MacOS

res = f_mkdir(&circuitpy->fatfs, "/.fseventsd");

if (res != FR_OK) {

return false;

}

make_empty_file(&circuitpy->fatfs, "/.fseventsd/no_log");

make_empty_file(&circuitpy->fatfs, "/.metadata_never_index");

// Prevent storing trash on all OSes.

make_empty_file(&circuitpy->fatfs, "/.Trashes"); // MacOS

make_empty_file(&circuitpy->fatfs, "/.Trash-1000"); // Linux, XDG trash spec:

// https://specifications.freedesktop.org/trash-spec/trashspec-latest.html

#endif

#if CIRCUITPY_SDCARDIO || CIRCUITPY_SDIOIO

res = f_mkdir(&circuitpy->fatfs, "/sd");

#if CIRCUITPY_FULL_BUILD

MAKE_FILE_WITH_OPTIONAL_CONTENTS(&circuitpy->fatfs, "/sd/placeholder.txt",

"SD cards mounted at /sd will hide this file from Python."

" SD cards are not visible via USB CIRCUITPY.\n");

#endif

#endif

#if CIRCUITPY_SAVES_PARTITION_SIZE > 0

res = f_mkfs(&saves->fatfs, formats, 0, working_buf, sizeof(working_buf));

if (res == FR_OK) {

// Flush the new file system to make sure it's repaired immediately.

supervisor_flash_flush();

res = f_setlabel(&saves->fatfs, "CPSAVES");

}

if (res == FR_OK) {

res = f_mkdir(&circuitpy->fatfs, "/saves");

}

#if CIRCUITPY_FULL_BUILD

if (res == FR_OK) {

MAKE_FILE_WITH_OPTIONAL_CONTENTS(&circuitpy->fatfs, "/saves/placeholder.txt",

"A separate filesystem mounted at /saves will hide this file from Python."

" Saves are visible via USB CPSAVES.\n");

}

#endif

#endif

#if CIRCUITPY_OS_GETENV

make_empty_file(&circuitpy->fatfs, "/settings.toml");

#endif

// make a sample code.py file

MAKE_FILE_WITH_OPTIONAL_CONTENTS(&circuitpy->fatfs, "/code.py", "print(\"Hello World!\")\n");

// create empty lib directory

res = f_mkdir(&circuitpy->fatfs, "/lib");

if (res != FR_OK) {

return false;

}

// and ensure everything is flushed

supervisor_flash_flush();

} else if (res != FR_OK) {

return false;

}

circuitpy_vfs->str = "/";

circuitpy_vfs->len = 1;

circuitpy_vfs->obj = MP_OBJ_FROM_PTR(circuitpy);

circuitpy_vfs->next = NULL;

MP_STATE_VM(vfs_mount_table) = circuitpy_vfs;

#if CIRCUITPY_SAVES_PARTITION_SIZE > 0

res = f_mount(&saves->fatfs);

if (res == FR_OK) {

mp_vfs_mount_t *saves_vfs = &_saves_vfs;

saves_vfs->str = "/saves";

saves_vfs->len = 6;

saves_vfs->obj = MP_OBJ_FROM_PTR(&_saves_usermount);

saves_vfs->next = MP_STATE_VM(vfs_mount_table);

MP_STATE_VM(vfs_mount_table) = saves_vfs;

}

#endif

// The current directory is used as the boot up directory.

// It is set to the internal flash filesystem by default.

MP_STATE_PORT(vfs_cur) = circuitpy_vfs;

#if CIRCUITPY_STORAGE_EXTEND

supervisor_flash_update_extended();

#endif

#if CIRCUITPY_SDCARDIO

sdcardio_init();

#endif

return true;

}

void PLACE_IN_ITCM(filesystem_flush)(void) {

// Reset interval before next flush.

filesystem_flush_interval_ms = CIRCUITPY_FILESYSTEM_FLUSH_INTERVAL_MS;

supervisor_flash_flush();

// Don't keep caches because this is called when starting or stopping the VM.

supervisor_flash_release_cache();

}

void filesystem_set_internal_writable_by_usb(bool writable) {

fs_user_mount_t *vfs = &_circuitpy_usermount;

filesystem_set_writable_by_usb(vfs, writable);

}

void filesystem_set_writable_by_usb(fs_user_mount_t *vfs, bool usb_writable) {

if (usb_writable) {

vfs->blockdev.flags |= MP_BLOCKDEV_FLAG_USB_WRITABLE;

} else {

vfs->blockdev.flags &= ~MP_BLOCKDEV_FLAG_USB_WRITABLE;

}

}

bool filesystem_is_writable_by_python(fs_user_mount_t *vfs) {

return (vfs->blockdev.flags & MP_BLOCKDEV_FLAG_CONCURRENT_WRITE_PROTECTED) == 0 ||

(vfs->blockdev.flags & MP_BLOCKDEV_FLAG_USB_WRITABLE) == 0;

}

bool filesystem_is_writable_by_usb(fs_user_mount_t *vfs) {

return (vfs->blockdev.flags & MP_BLOCKDEV_FLAG_CONCURRENT_WRITE_PROTECTED) == 0 ||

(vfs->blockdev.flags & MP_BLOCKDEV_FLAG_USB_WRITABLE) != 0;

}

void filesystem_set_internal_concurrent_write_protection(bool concurrent_write_protection) {

filesystem_set_concurrent_write_protection(&_circuitpy_usermount, concurrent_write_protection);

}

void filesystem_set_concurrent_write_protection(fs_user_mount_t *vfs, bool concurrent_write_protection) {

if (concurrent_write_protection) {

vfs->blockdev.flags |= MP_BLOCKDEV_FLAG_CONCURRENT_WRITE_PROTECTED;

} else {

vfs->blockdev.flags &= ~MP_BLOCKDEV_FLAG_CONCURRENT_WRITE_PROTECTED;

}

}

bool filesystem_present(void) {

return _circuitpy_vfs.len > 0;

}

fs_user_mount_t *filesystem_circuitpy(void) {

if (!filesystem_present()) {

return NULL;

}

return &_circuitpy_usermount;

}

fs_user_mount_t *filesystem_for_path(const char *path_in, const char **path_under_mount) {

mp_vfs_mount_t *vfs = mp_vfs_lookup_path(path_in, path_under_mount);

if (vfs == MP_VFS_NONE) {

return NULL;

}

fs_user_mount_t *fs_mount;

*path_under_mount = path_in;

if (vfs == MP_VFS_ROOT) {

fs_mount = filesystem_circuitpy();

} else {

fs_mount = MP_OBJ_TO_PTR(vfs->obj);

// Check if the vfs name is one character long: it must be "/" in that case.

// If so don't remove the mount point name. We must use an absolute path

// because otherwise the path will be adjusted by os.getcwd() when it's looked up.

if (strlen(vfs->str) != 1) {

// Remove the mount point directory name, such as "/sd".

*path_under_mount += strlen(vfs->str);

}

}

return fs_mount;

}

bool filesystem_native_fatfs(fs_user_mount_t *fs_mount) {

return fs_mount->base.type == &mp_fat_vfs_type && (fs_mount->blockdev.flags & MP_BLOCKDEV_FLAG_NATIVE) != 0;

}

bool filesystem_lock(fs_user_mount_t *fs_mount) {

if (fs_mount->lock_count == 0 && !blockdev_lock(fs_mount)) {

return false;

}

fs_mount->lock_count += 1;

return true;

}

void filesystem_unlock(fs_user_mount_t *fs_mount) {

fs_mount->lock_count -= 1;

if (fs_mount->lock_count == 0) {

blockdev_unlock(fs_mount);

}

}

bool blockdev_lock(fs_user_mount_t *fs_mount) {

if ((fs_mount->blockdev.flags & MP_BLOCKDEV_FLAG_LOCKED) != 0) {

return false;

}

fs_mount->blockdev.flags |= MP_BLOCKDEV_FLAG_LOCKED;

return true;

}

void blockdev_unlock(fs_user_mount_t *fs_mount) {

fs_mount->blockdev.flags &= ~MP_BLOCKDEV_FLAG_LOCKED;

}