Other than patching Scylla sinks to implement new data_sink_impl::put(std::span<temporary_buffer>) overload, the PR changes transport write_response() method to stop using output_stream::write(scattered_message) because it's also gone.
Using newer seastar API, no need to backport
Closesscylladb/scylladb#26592
* github.com:scylladb/scylladb:
code: Fix indentation after previous patch
code: Switch to seastar API level 9
transport: Open-code invoke_with_counting into counting_data_sink::put
transport: Don't use scattered_message
utils: Implement memory_data_sink::put(net::packet)
In the new API the biggest change is to implement the only
data_sink_impl::put(span<temporary_buffer>) overload.
Encrypted file impl and sstables compress sink use fallback_put() helper
that generates a chain of continuations each holding a buffer.
The counting_data_sink in transport had mostly been patched to correct
implementation by the previous patch, the change here is to replace
vector argument with span one.
Most other sinks just re-implement their put(vector<temporary_buffer>)
overload by iterating over span and non-preemptively grabbing buffers
from it.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Mainly to add a somewhat functional file-impl wrapping
a data_sink. This can implement a rudimentary, write-only,
file based on any output sink.
For testing, and because they fit there, place memory
sink and source types there as well.
