This changes crypt's use of sync.Pool: Instead of storing slices
it now stores pointers pointers fixed sized arrays.
This issue was reported by staticcheck:
SA6002 - Storing non-pointer values in sync.Pool allocates memory
A sync.Pool is used to avoid unnecessary allocations and reduce
the amount of work the garbage collector has to do.
When passing a value that is not a pointer to a function that accepts
an interface, the value needs to be placed on the heap, which means
an additional allocation. Slices are a common thing to put in sync.Pools,
and they're structs with 3 fields (length, capacity, and a pointer to
an array). In order to avoid the extra allocation, one should store
a pointer to the slice instead.
See: https://staticcheck.io/docs/checks#SA6002
Before this change the code wasn't taking into account the error
io.ErrUnexpectedEOF that io.ReadFull can return properly. Sometimes
that error was being returned instead of a more specific and useful
error.
To fix this, io.ReadFull was replaced with the simpler
readers.ReadFill which is much easier to use correctly.
This is possible now that we no longer support go1.12 and brings
rclone into line with standard practices in the Go world.
This also removes errors.New and errors.Errorf from lib/errors and
prefers the stdlib errors package over lib/errors.
With the file version format standardized in lib/version, `crypt` can
now treat the version strings separately from the encrypted/decrypted
file names. This allows --b2-versions to work with `crypt`.
Fixes#1627
Co-authored-by: Luc Ritchie <luc.ritchie@gmail.com>
- 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.
