package bin_prot

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Utility functions for user convenience

val size_header_length : int

size_header_length is the standard number of bytes allocated for the size header in size-prefixed bin-io payloads. This size-prefixed layout is used by the bin_dump and bin_read_stream functions below, as well as:

  • Core.Unpack_buffer.unpack_bin_prot
  • Async.


    .read,write_bin_prot among others.

The size prefix is always 8 bytes at present. This is exposed so your program does not have to know this fact too.

We do not use a variable length header because we want to know how many bytes to read to get the size without having to peek into the payload.

val bin_read_size_header : int Read.reader
val bin_write_size_header : int Write.writer

bin_read_size_header and bin_write_size_header are bin-prot serializers for the size header described above.

val bin_dump : ?header:bool -> 'a Type_class.writer -> 'a -> Common.buf

bin_dump ?header writer v uses writer to first compute the size of v in the binary protocol, then allocates a buffer of exactly this size, and then writes out the value. If header is true, the size of the resulting binary string will be prefixed as a signed 64bit integer.

  • returns

    the buffer containing the written out value.

  • parameter header

    default = false

  • raises Failure

    if the size of the value changes during writing, and any other exceptions that the binary writer in writer can raise.

val bin_read_stream : ?max_size:int -> read:(Common.buf -> pos:int -> len:int -> unit) -> 'a Type_class.reader -> 'a

bin_read_stream ?max_size ~read reader reads binary protocol data from a stream as generated by the read function, which places data of a given length into a given buffer. Requires a header. The reader type class will be used for conversion to OCaml-values.

  • parameter max_size

    = nothing

  • raises Failure

    if the size of the value disagrees with the one specified in the header, and any other exceptions that the binary reader associated with reader can raise.

  • raises Failure

    if the size reported in the data header is longer than max_size.

Conversion of binable types

module type Make_binable_spec = sig ... end
module Of_minimal (S : Binable.Minimal.S) : Binable.S with type t := S.t
module type Make_binable1_spec = sig ... end
module type Make_binable2_spec = sig ... end
module Make_binable2 (Bin_spec : Make_binable2_spec) : Binable.S2 with type ('a, 'b) t := ('a, 'b) Bin_spec.t
module type Make_binable3_spec = sig ... end
module Make_binable3 (Bin_spec : Make_binable3_spec) : Binable.S3 with type ('a, 'b, 'c) t := ('a, 'b, 'c) Bin_spec.t

Conversion of iterable types

module type Make_iterable_binable_spec = sig ... end
module type Make_iterable_binable1_spec = sig ... end
module type Make_iterable_binable2_spec = sig ... end
module type Make_iterable_binable3_spec = sig ... end