Source file iOVec.ml

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type 'a t = 'a Faraday.iovec =
  { buffer : 'a
  ; off : int
  ; len : int }

let length { len; _ } = len
let lengthv iovs = List.fold_left (fun acc { len; _ } -> acc + len) 0 iovs

let shift { buffer; off; len } n =
  assert (n <= len);
  { buffer; off = off + n; len = len - n }

let rec shiftv iovecs n =
  if n = 0
  then iovecs
  else match iovecs with
  | []            -> failwith "shiftv: n >= lengthv iovecs"
  | iovec::iovecs ->
    let len = length iovec in
    if len >= n
    then shiftv iovecs (n - len)
    else (shift iovec len)::iovecs

let add_len { buffer; off; len } n =
  { buffer; off; len = len + n }