stream_identifier.ml

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(* From RFC7540§5.1.1:
 *   Streams are identified with an unsigned 31-bit integer. *)
type t = int32

let ( === ) = Int32.equal
let[@inline] ( <= ) s1 s2 = Int32.compare s1 s2 <= 0
let[@inline] ( > ) s1 s2 = Int32.compare s1 s2 > 0
let[@inline] ( >= ) s1 s2 = Int32.compare s1 s2 >= 0

(* From RFC7540§5.1.1:
 *   A stream identifier of zero (0x0) is used for connection control messages;
 *   the stream identifier of zero cannot be used to establish a new stream. *)
let connection = Int32.zero

(* From RFC7540§5.1.1:
 *   A stream identifier of zero (0x0) is used for connection control messages;
 *   the stream identifier of zero cannot be used to establish a new stream. *)
let[@inline] is_connection id = Int32.equal id connection

(* From RFC7540§5.1.1:
 *   Streams initiated by a client MUST use odd-numbered stream
 *   identifiers [...]. *)
let[@inline] is_request id = Int32.rem id 2l === 1l

(* From RFC7540§5.1.1:
 *   Streams initiated by [...] the server MUST use even-numbered stream
 *   identifiers. A stream identifier of zero (0x0) is used for connection
 *   control messages [...]. *)
let[@inline] is_pushed = function 0l -> false | n -> Int32.rem n 2l === 0l

(* From RFC7540§5.1.1:
 *   Streams are identified with an unsigned 31-bit integer. *)
let max_stream_id = Int32.max_int