The written out list of tests was replaced with a nested test for
mount and cmount. The tests for each VFS cache mode were also replaced
with nested tests which makes the output and the code much cleaner.
Previously this was adding it in to all file opens which was causing
inefficiencies under Windows where it stats the file using
open/fstat/close.
This change will make stat operations run much quicker under Windows
as they won't have to open the underlying file
This problem was introduced in61b6159a05336bd7ba105766de2d2ff171f7fb81
where we added O_CREATE to all file opens and creates.
This flag allows the attribute caching in the kernel to be controlled.
The default is 0s - no caching - which is recommended for filesystems
which can change outside the control of the kernel.
Previously this was at the default meaning it was 60s for mount and 1s
for cmount. This showed strange effects when files changed on the
remote not via the kernel. For instance Caddy would serve corrupted
files for a while when serving from an rclone mount when a file
changed on the remote.
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.
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.
On Windows the fuse.O_* flags do not have the same values as the
os.O_* flags so translate between the two representations. They are
mostly the same which is why this hasn't caused a problem before.
* 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
Normally mount/cmount use `-o ro` to get the kernel to mark the fs as
read only. However this is ignored by WinFsp, so in addition if
`--read-only` is in effect then return EROFS ("Read only File System")
from all methods which attempt to modify something.
