flags.ml

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open Util

type t = int

(* From RFC7540§6.2:
 *   Flags that have no defined semantics for a particular frame type MUST be
 *   ignored and MUST be left unset (0x0) when sending. *)
let default_flags = 0x0

(* From RFC7540§6.2:
 *   END_STREAM (0x1): When set, bit 0 indicates that the header block (Section
 *   4.3) is the last that the endpoint will send for the identified stream. *)
let test_end_stream x = test_bit x 0
let set_end_stream x = set_bit x 0
let clear_end_stream x = clear_bit x 0

(* From RFC7540§6.7:
 *   ACK (0x1): When set, bit 0 indicates that this PING frame is a PING
 *   response. *)
let test_ack x = test_bit x 0
let set_ack x = set_bit x 0

(* From RFC7540§6.2:
 *   END_HEADERS (0x4): When set, bit 2 indicates that this frame contains an
 *   entire header block (Section 4.3) and is not followed by any CONTINUATION
 *   frames. *)
let test_end_header x = test_bit x 2
let set_end_header x = set_bit x 2

(* From RFC7540§6.2:
 *   PADDED (0x8): When set, bit 3 indicates that the Pad Length field and any
 *   padding that it describes are present. *)
let test_padded x = test_bit x 3
let set_padded x = set_bit x 3

(* From RFC7540§6.2:
 *   PRIORITY (0x20): When set, bit 5 indicates that the Exclusive Flag (E),
 *   Stream Dependency, and Weight fields are present; see Section 5.3. *)
let test_priority x = test_bit x 5
let set_priority x = set_bit x 5