Commit Graph

2 Commits

Author SHA1 Message Date
Damien George 0e6ef40359 tests/extmod: Add tests for verifying FAT and littlefs mtime values.
Verifies mtime timestamps on files match the value returned by time.time().

Also update vfs_fat_ramdisk.py so it doesn't check FAT timestamp of the
root, because that may change across runs/ports.

Signed-off-by: Damien George <damien@micropython.org>
2020-09-02 00:19:38 +10:00
Damien George 2acc087880 extmod/vfs_lfs: Add mtime support to littlefs files.
This commit adds support for modification time of files on littlefs v2
filesystems, using file attributes.  For some background see issue #6114.

Features/properties of this implementation:
- Only supported on littlefs2 (not littlefs1).
- Uses littlefs2's general file attributes to store the timestamp.
- The timestamp is 64-bits and stores nanoseconds since 1970/1/1 (if the
  range to the year 2554 is not enough then additional bits can be added to
  this timestamp by adding another file attribute).
- mtime is enabled by default but can be disabled in the constructor, eg:
  uos.mount(uos.VfsLfs2(bdev, mtime=False), '/flash')
- It's fully backwards compatible, existing littlefs2 filesystems will work
  without reformatting and timestamps will be added transparently to
  existing files (once they are opened for writing).
- Files without timestamps will open correctly, and stat will just return 0
  for their timestamp.
- mtime can be disabled or enabled each mount time and timestamps will only
  be updated if mtime is enabled (otherwise they will be untouched).

Signed-off-by: Damien George <damien@micropython.org>
2020-08-25 17:35:19 +10:00