On file Remove
- cancel any writebacks in progress
- ignore error message deleting non existent file if file was in the
process of being uploaded
Writeback
- Don't transfer the file if it has disappeared in the meantime
- Take our own copy of the file name to avoid deadlocks
- Fix delayed retry logic
- Wait for upload to finish when cancelling upload
Fix race condition in item saving
Fix race condition in vfscache test
Make sure we delete the file on the error path - this makes cascading
failures much less likely
This allows reads to only read part of the file and it keeps on disk a
cache of what parts of each file have been loaded.
File data itself is kept in sparse files.
Previously we were using f which calls f.String() which calls f.Path()
which can cause a deadlock if uses carelessly.
This patch explicitly calls f.Path() or f._path() to bring attention
to the fact that there is a call to a method.
As part of this we take a copy of the directory path as calling
d.Path() violates the total locking order.
See the comment at the top of file.go for details
When a file has its modtime set while it is open we delay setting the
modtime until the file is closed.
The file is then uploaded in Flush. In Release we check the cached
file has been uploaded by comparing modtimes and or hashes and upload
it again if it has changed.
Before this change we forgot to change the time on the cached file
when we updated the time file on the object, so this mean that Release
reset the time to the wrong time and uploaded the file again on
remotes which don't support hashes (eg crypt).
The fix was to set the modtime of the cached file at the same time we
set the modtime of the remote object. This means that the files check
as identical in Release so it doesn't try to upload the file.
This means that we avoid a double upload and the modtime is correct.
See: https://forum.rclone.org/t/modification-time-with-vfs-cache/13906/8
Before this change, when uploading files from the VFS cache which were
pending a rename, rclone would use the new path of the object when
specifiying the destination remote. This didn't cause a problem with
most backends as the subsequent rename did nothing, however with the
drive backend, since it updates objects, the incorrect Remote was
embedded in the object. This caused the rename to apparently succeed
but the object be at the wrong location.
The fix for this was to make sure we upload to the path stored in the
object if available.
This problem was spotted by the new rename tests for the VFS layer.
Before this change, renaming an open file when using the VFS cache was
delayed until the file was closed. This meant that the file was not
readable after a rename even though it is was in the cache.
After this change we rename the local cache file and the in memory
cache, delaying only the rename of the file in object storage.
See: https://forum.rclone.org/t/xen-orchestra-ebadf-bad-file-descriptor-write/13104
Before this change, with --vfs-cache-mode minimal,writes if files were
opened they would always be read from the remote, regardless of
whether they were in the cache or not.
This change checks to see if the file is in the cache when opening a
file with --vfs-cache-mode >= minimal and if so then it uses it from
the cache.
This makes --vfs-cache-mode writes in particular much more
efficient. No longer is a file uploaded (with write mode) then
immediately downloaded (with read only mode).
Fixes#3330
- Change rclone/fs interfaces to accept context.Context
- Update interface implementations to use context.Context
- Change top level usage to propagate context to lover level functions
Context propagation is needed for stopping transfers and passing other
request-scoped values.
This fixes FreeBSD which seems to call SetAttr with a size even on
read only files.
This is probably a bug in the FreeBSD FUSE implementation as it
happens with mount and cmount.
See: https://forum.rclone.org/t/freebsd-question/8662/12
Before this change we took the locks file.mu and file.muRW in an
inconsistent order - after the change we always take them in the same
order to fix the deadlock.
Before this fix there were two paths where concurrent use of a
directory could take the file lock then directory lock and the other
would take the locks in the reverse order.
Fix this by narrowing the locking windows so the file lock and
directory lock don't overlap.
Before this change remotes without server side Move (eg swift, s3,
gcs) would not be able to rename files.
After it means nearly all remotes will be able to rename files on
rclone mount with the notable exceptions of b2 and yandex.
This changes checks to see if the remote can do Move or Copy then
calls `operations.Move` to do the actual move. This will do a server
side Move or Copy but won't download and re-upload the file.
It also checks to see if the destination exists first which avoids
conflicts or duplicates.
Fixes#1965Fixes#2569
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.
