package mirage-protocols
Library
Module
Module type
Parameter
Class
Class type
Transmission Control Protocol layer: reliable ordered streaming communication.
The type for TCP errors.
The type for TCP write errors.
Disconnect from the TCP layer. While this might take some time to complete, it can never result in an error.
include Mirage_flow.S
with type flow := flow
and type error := error
and type write_error := write_error
val pp_write_error : write_error Fmt.t
pp_write_error
is the pretty-printer for write errors.
read flow
blocks until some data is available and returns a fresh buffer containing it.
The returned buffer will be of a size convenient to the flow implementation, but will always have at least 1 byte.
If the remote endpoint calls close
then calls to read
will keep returning data until all the in-flight data has been read. read flow
will return `Eof
when the remote endpoint has called close
and when there is no more in-flight data.
val write : flow -> Cstruct.t -> (unit, write_error) result Lwt.t
write flow buffer
writes a buffer to the flow. There is no indication when the buffer has actually been read and, therefore, it must not be reused. The contents may be transmitted in separate packets, depending on the underlying transport. The result Ok ()
indicates success, Error `Closed
indicates that the connection is now closed and therefore the data could not be written. Other errors are possible.
val writev : flow -> Cstruct.t list -> (unit, write_error) result Lwt.t
writev flow buffers
writes a sequence of buffers to the flow. There is no indication when the buffers have actually been read and, therefore, they must not be reused. The result Ok ()
indicates success, Error `Closed
indicates that the connection is now closed and therefore the data could not be written. Other errors are possible.
close flow
flushes all pending writes and signals the remote endpoint that there will be no future writes. Once the remote endpoint has read all pending data, it is expected that calls to read
on the remote return `Eof
.
Note it is still possible for the remote endpoint to write
to the flow and for the local endpoint to call read
. This state where the local endpoint has called close
but the remote endpoint has not called close
is similar to that of a half-closed TCP connection or a Unix socket after shutdown(SHUTDOWN_WRITE)
.
close flow
waits until the remote endpoint has also called close
before returning. At this point no data can flow in either direction and resources associated with the flow can be freed.
Get the destination IP address and destination port that a flow is currently connected to.
val write_nodelay : flow -> Cstruct.t -> (unit, write_error) result Lwt.t
write_nodelay flow buffer
writes the contents of buffer
to the flow. The thread blocks until all data has been successfully transmitted to the remote endpoint. Buffering within the layer is minimized in this mode. Note that this API will change in a future revision to be a per-flow attribute instead of a separately exposed function.
val writev_nodelay : flow -> Cstruct.t list -> (unit, write_error) result Lwt.t
writev_nodelay flow buffers
writes the contents of buffers
to the flow. The thread blocks until all data has been successfully transmitted to the remote endpoint. Buffering within the layer is minimized in this mode. Note that this API will change in a future revision to be a per-flow attribute instead of a separately exposed function.
create_connection ~keepalive t (addr,port)
opens a TCP connection to the specified endpoint.
If the optional argument ?keepalive
is provided then TCP keep-alive messages will be sent to the server when the connection is idle. If no responses are received then eventually the connection will be disconnected: read
will return Ok `Eof
and write will return Error `Closed
val listen :
t ->
port:int ->
?keepalive:Keepalive.t ->
(flow -> unit Lwt.t) ->
unit
listen t ~port ~keepalive callback
listens on port
. The callback
is executed for each flow that was established. If keepalive
is provided, this configuration will be applied before calling callback
.
val unlisten : t -> port:int -> unit
unlisten t ~port
stops any listener on port
.