This stops the cache cleaner running unnecessarily and saves
resources.
This also helps with issue #2227 which was caused by a second mount
deleting objects in the first mounts cache.
Without this fix the cached file can be removed as the file is being
uploaded or downloaded. This can cause the directory listings to
become inconsistent (this issue) or data loss (if a retry was needed
in the Copy).
Remove file needs to be excluded from running at the same time as both
openPending and close so it makes sense to unify the locking between
all 3.
This was caused by this sequence of calls
1> file.Release
1> file.close -> takes the file lock
2> vfs.waitforWriters
2> dir.walk -> takes the dir lock
1> file.setObject
1> dir.addObject -> attempts to take the dir lock - BLOCKS
2> file.activeWriters -> tries to take file lock - BLOCKS - DEADLOCK
The fix is to make activeWriters not take the file lock and use atomic
operations to read the number of writers instead.
Before this change Open("name", os.O_RDONLY|os.O_TRUNC) would have
truncated the file. This is what Linux does, but is counterintuitive.
POSIX states this is undefined, so return an error in this case
instead. This preserves the invariant O_RDONLY => file is not
changed.
This means that Google docs will no longer appear as huge files in
`rclone mount`. They will not be downloadable, though sometimes
trying twice will work.
The purpose of this is to make it easier to maintain and eventually to
allow the rclone backends to be re-used in other projects without
having to use the rclone configuration system.
The new code layout is documented in CONTRIBUTING.
If we open a file for r/w without the cache we now always return a
handle and return an error if the file is ever read from. This fixes
incompatibility with cmount under windows.
This adds new flags to mount, cmount, serve *
--cache-max-age duration Max age of objects in the cache. (default 1h0m0s)
--cache-mode string Cache mode off|minimal|writes|full (default "off")
--cache-poll-interval duration Interval to poll the cache for stale objects. (default 1m0s)
* Tests for VFS layer
* Small fixes found during testing
* Fix Close, Flush and Release behaviour for ReadFileHandle and WriteFileHandle
* Fix nil object bugs on File
