module Unpack_one:sig
..end
unpack_one : ('value, 'partial_unpack) unpack_one
, then unpack_one buf ?pos
?len ?partial_unpack
must unpack at most one value of type 'value
from buf
starting at pos
, and not using more than len
characters. unpack_one
must
returns one the following:
`Ok (value, n) -- unpacking succeeded and consumed n
bytes
`Not_enough_data (p, n) -- unpacking encountered a valid proper prefix of a packed
value, and consumed n
bytes (0 <= n <= len). p
is a "partial unpack" that can
be supplied to a future call to unpack_one
to continue unpacking
`Invalid_data -- unpacking encountered an invalidly packed value
A naive unpack_one
that only succeeds on a fully packed value could lead to
quadratic behavior if a packed value's bytes are input using a linear number of
calls to feed
.
type('value, 'partial_unpack)
t =?partial_unpack:'partial_unpack ->
?pos:int ->
?len:int ->
Bigstring.t ->
[ `Invalid_data of Error.t
| `Not_enough_data of 'partial_unpack * int
| `Ok of 'value * int ]
val map : ('a, 'partial_unpack) t ->
f:('a -> 'b) -> ('b, 'partial_unpack) t
val create_bin_prot : 'a Bin_prot.Type_class.reader -> ('a, unit) t
create_bin_prot reader
returns an unpacker that reads the "size-prefixed" bin_prot
encoding, in which a value is encoded by first writing the length of the bin_prot
data as a 64-bit int, and then writing the data itself. This encoding makes it
trivial to know if enough data is available in the buffer, so there is no need to
represent partially unpacked values, and hence 'partial_unpack = unit
.