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module Uchar_ = Uchar
module OCaml4_14 = struct
module Uchar = struct
type utf_decode = int
let rep = 0xFFFD
let valid_bit = 27
let decode_bits = 24
let[@inline] utf_decode_is_valid d = d lsr valid_bit = 1
let[@inline] utf_decode_length d = (d lsr decode_bits) land 0b111
let[@inline] utf_decode_uchar d = Uchar.unsafe_of_int (d land 0xFFFFFF)
let[@inline] utf_decode n u = ((8 lor n) lsl decode_bits) lor Uchar.to_int u
let[@inline] utf_decode_invalid n = (n lsl decode_bits) lor rep
let utf_8_byte_length u =
match Uchar.to_int u with
| u when u < 0 -> assert false
| u when u <= 0x007F -> 1
| u when u <= 0x07FF -> 2
| u when u <= 0xFFFF -> 3
| u when u <= 0x10FFFF -> 4
| _ -> assert false
let utf_16_byte_length u =
match Uchar.to_int u with
| u when u < 0 -> assert false
| u when u <= 0xFFFF -> 2
| u when u <= 0x10FFFF -> 4
| _ -> assert false
end
module String = struct
let[@inline] not_in_x80_to_xBF b = b lsr 6 <> 0b10
let[@inline] not_in_xA0_to_xBF b = b lsr 5 <> 0b101
let[@inline] not_in_x80_to_x9F b = b lsr 5 <> 0b100
let[@inline] not_in_x90_to_xBF b = b < 0x90 || 0xBF < b
let[@inline] not_in_x80_to_x8F b = b lsr 4 <> 0x8
let[@inline] utf_8_uchar_2 b0 b1 = ((b0 land 0x1F) lsl 6) lor (b1 land 0x3F)
let[@inline] utf_8_uchar_3 b0 b1 b2 =
((b0 land 0x0F) lsl 12) lor ((b1 land 0x3F) lsl 6) lor (b2 land 0x3F)
let[@inline] utf_8_uchar_4 b0 b1 b2 b3 =
((b0 land 0x07) lsl 18)
lor ((b1 land 0x3F) lsl 12)
lor ((b2 land 0x3F) lsl 6)
lor (b3 land 0x3F)
let[@inline] dec_ret n u = Uchar.utf_decode n (Uchar_.unsafe_of_int u)
let dec_invalid = Uchar.utf_decode_invalid
let get_utf_8_uchar s i =
let b = Bytes.unsafe_of_string s in
let b0 = Bytes.get_uint8 b i in
let get = Bytes.get_uint8 in
let max = Bytes.length b - 1 in
match Char.unsafe_chr b0 with
| '\x00' .. '\x7F' -> dec_ret 1 b0
| '\xC2' .. '\xDF' ->
let i = i + 1 in
if i > max then dec_invalid 1
else
let b1 = get b i in
if not_in_x80_to_xBF b1 then dec_invalid 1
else dec_ret 2 (utf_8_uchar_2 b0 b1)
| '\xE0' ->
let i = i + 1 in
if i > max then dec_invalid 1
else
let b1 = get b i in
if not_in_xA0_to_xBF b1 then dec_invalid 1
else
let i = i + 1 in
if i > max then dec_invalid 2
else
let b2 = get b i in
if not_in_x80_to_xBF b2 then dec_invalid 2
else dec_ret 3 (utf_8_uchar_3 b0 b1 b2)
| '\xE1' .. '\xEC' | '\xEE' .. '\xEF' ->
let i = i + 1 in
if i > max then dec_invalid 1
else
let b1 = get b i in
if not_in_x80_to_xBF b1 then dec_invalid 1
else
let i = i + 1 in
if i > max then dec_invalid 2
else
let b2 = get b i in
if not_in_x80_to_xBF b2 then dec_invalid 2
else dec_ret 3 (utf_8_uchar_3 b0 b1 b2)
| '\xED' ->
let i = i + 1 in
if i > max then dec_invalid 1
else
let b1 = get b i in
if not_in_x80_to_x9F b1 then dec_invalid 1
else
let i = i + 1 in
if i > max then dec_invalid 2
else
let b2 = get b i in
if not_in_x80_to_xBF b2 then dec_invalid 2
else dec_ret 3 (utf_8_uchar_3 b0 b1 b2)
| '\xF0' ->
let i = i + 1 in
if i > max then dec_invalid 1
else
let b1 = get b i in
if not_in_x90_to_xBF b1 then dec_invalid 1
else
let i = i + 1 in
if i > max then dec_invalid 2
else
let b2 = get b i in
if not_in_x80_to_xBF b2 then dec_invalid 2
else
let i = i + 1 in
if i > max then dec_invalid 3
else
let b3 = get b i in
if not_in_x80_to_xBF b3 then dec_invalid 3
else dec_ret 4 (utf_8_uchar_4 b0 b1 b2 b3)
| '\xF1' .. '\xF3' ->
let i = i + 1 in
if i > max then dec_invalid 1
else
let b1 = get b i in
if not_in_x80_to_xBF b1 then dec_invalid 1
else
let i = i + 1 in
if i > max then dec_invalid 2
else
let b2 = get b i in
if not_in_x80_to_xBF b2 then dec_invalid 2
else
let i = i + 1 in
if i > max then dec_invalid 3
else
let b3 = get b i in
if not_in_x80_to_xBF b3 then dec_invalid 3
else dec_ret 4 (utf_8_uchar_4 b0 b1 b2 b3)
| '\xF4' ->
let i = i + 1 in
if i > max then dec_invalid 1
else
let b1 = get b i in
if not_in_x80_to_x8F b1 then dec_invalid 1
else
let i = i + 1 in
if i > max then dec_invalid 2
else
let b2 = get b i in
if not_in_x80_to_xBF b2 then dec_invalid 2
else
let i = i + 1 in
if i > max then dec_invalid 3
else
let b3 = get b i in
if not_in_x80_to_xBF b3 then dec_invalid 3
else dec_ret 4 (utf_8_uchar_4 b0 b1 b2 b3)
| _ -> dec_invalid 1
end
end