stringExt.ml

(*
  Atari Jaguar Removers' Linker
  Copyright (C) 2014-2017 Seb/The Removers (SebRmv@jagware.org)

  This program is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program.  If not, see <http://www.gnu.org/licenses/>.
*)

let split sep s =
  let n = String.length s in
  let rec aux start i =
    if i < n then
      if s.[i] = sep then String.sub s start (i - start) :: aux (i + 1) (i + 1)
      else aux start (i + 1)
    else [ String.sub s start (i - start) ]
  in
  aux 0 0

let rev_split sep s =
  let n = String.length s in
  let rec aux accu start i =
    if i < n then
      if s.[i] = sep then
        aux (String.sub s start (i - start) :: accu) (i + 1) (i + 1)
      else aux accu start (i + 1)
    else String.sub s start (i - start) :: accu
  in
  aux [] 0 0

let trim_start p s =
  let n = String.length s in
  let rec aux i =
    if i < n then if p s.[i] then aux (i + 1) else String.sub s i (n - i)
    else ""
  in
  aux 0

let trim_end p s =
  let n = String.length s in
  let rec aux i =
    if 0 <= i then if p s.[i] then aux (i - 1) else String.sub s 0 (i + 1)
    else ""
  in
  aux (n - 1)

let read_byte s offset =
  let n = String.length s in
  if 0 <= offset && offset < n then Int32.of_int (Char.code s.[offset])
  else raise (Invalid_argument "read_byte")

let read_word s offset =
  let n = String.length s in
  if 0 <= offset && offset + 1 < n then
    let hi = Char.code s.[offset] in
    let lo = Char.code s.[offset + 1] in
    Int32.of_int ((hi lsl 8) lor lo)
  else raise (Invalid_argument "read_word")

let read_long s offset =
  let n = String.length s in
  if 0 <= offset && offset + 3 < n then
    let hh = Char.code s.[offset] in
    let hl = Char.code s.[offset + 1] in
    let lh = Char.code s.[offset + 2] in
    let ll = Char.code s.[offset + 3] in
    let hi = Int32.of_int ((hh lsl 8) lor hl) in
    let lo = Int32.of_int ((lh lsl 8) lor ll) in
    Int32.logor (Int32.shift_left hi 16) lo
  else raise (Invalid_argument "read_long")

let read_string s offset sep =
  let n = String.length s in
  if 0 <= offset && offset < n then begin
    let i = ref offset in
    while !i < n && s.[!i] <> sep do
      incr i
    done;
    if !i < n then String.sub s offset (!i - offset)
    else raise (Invalid_argument "read_string")
  end
  else raise (Invalid_argument "read_string")

let read_substring s offset len =
  let n = String.length s in
  if 0 <= offset && offset + len <= n then String.sub s offset len
  else raise (Invalid_argument "read_substring")