swh:1:snp:61dcfc0dd5674a0e65803e88039c122d9532074e
Tip revision: 2f78f358756446cc4b730c635dc1c18392237a5f authored by Raphaƫl Proust on 03 February 2021, 15:26:55 UTC
Merge branch 'prepare-for-v0.3' into 'master'
Merge branch 'prepare-for-v0.3' into 'master'
Tip revision: 2f78f35
binary_length.ml
(*****************************************************************************)
(* *)
(* Open Source License *)
(* Copyright (c) 2018 Dynamic Ledger Solutions, Inc. <contact@tezos.com> *)
(* *)
(* Permission is hereby granted, free of charge, to any person obtaining a *)
(* copy of this software and associated documentation files (the "Software"),*)
(* to deal in the Software without restriction, including without limitation *)
(* the rights to use, copy, modify, merge, publish, distribute, sublicense, *)
(* and/or sell copies of the Software, and to permit persons to whom the *)
(* Software is furnished to do so, subject to the following conditions: *)
(* *)
(* The above copyright notice and this permission notice shall be included *)
(* in all copies or substantial portions of the Software. *)
(* *)
(* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR*)
(* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, *)
(* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL *)
(* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER*)
(* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING *)
(* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER *)
(* DEALINGS IN THE SOFTWARE. *)
(* *)
(*****************************************************************************)
open Binary_error_types
let n_length value =
let bits = Z.numbits value in
if bits = 0 then 1 else (bits + 6) / 7
let z_length value = (Z.numbits value + 1 + 6) / 7
let rec length : type x. x Encoding.t -> x -> int =
fun e value ->
let open Encoding in
match e.encoding with
(* Fixed *)
| Null ->
0
| Empty ->
0
| Constant _ ->
0
| Bool ->
Binary_size.bool
| Int8 ->
Binary_size.int8
| Uint8 ->
Binary_size.uint8
| Int16 ->
Binary_size.int16
| Uint16 ->
Binary_size.uint16
| Int31 ->
Binary_size.int31
| Int32 ->
Binary_size.int32
| Int64 ->
Binary_size.int64
| N ->
n_length value
| Z ->
z_length value
| RangedInt {minimum; maximum} ->
Binary_size.integer_to_size
@@ Binary_size.range_to_size ~minimum ~maximum
| Float ->
Binary_size.float
| RangedFloat _ ->
Binary_size.float
| Bytes (`Fixed n) ->
n
| String (`Fixed n) ->
n
| Padded (e, n) ->
length e value + n
| String_enum (_, arr) ->
Binary_size.integer_to_size @@ Binary_size.enum_size arr
| Objs {kind = `Fixed n; _} ->
n
| Tups {kind = `Fixed n; _} ->
n
| Union {kind = `Fixed n; _} ->
n
(* Dynamic *)
| Objs {kind = `Dynamic; left; right} ->
let (v1, v2) = value in
length left v1 + length right v2
| Tups {kind = `Dynamic; left; right} ->
let (v1, v2) = value in
length left v1 + length right v2
| Mu {kind = `Dynamic; fix; _} ->
length (fix e) value
| Obj (Opt {kind = `Dynamic; encoding = e; _}) -> (
match value with None -> 1 | Some value -> 1 + length e value )
(* Variable *)
| Ignore ->
0
| Bytes `Variable ->
Bytes.length value
| String `Variable ->
String.length value
| Array (Some max_length, _e) when Array.length value > max_length ->
raise (Write_error Array_too_long)
| Array (_, e) ->
Array.fold_left (fun acc v -> length e v + acc) 0 value
| List (Some max_length, _e) when List.length value > max_length ->
raise (Write_error List_too_long)
| List (_, e) ->
List.fold_left (fun acc v -> length e v + acc) 0 value
| Objs {kind = `Variable; left; right} ->
let (v1, v2) = value in
length left v1 + length right v2
| Tups {kind = `Variable; left; right} ->
let (v1, v2) = value in
length left v1 + length right v2
| Obj (Opt {kind = `Variable; encoding = e; _}) -> (
match value with None -> 0 | Some value -> length e value )
| Mu {kind = `Variable; fix; _} ->
length (fix e) value
(* Variable or Dynamic we don't care for those constructors *)
| Union {kind = `Dynamic | `Variable; tag_size; match_case; _} ->
let (Matched (tag, e, value)) = match_case value in
assert (tag <= Binary_size.max_int tag_size) ;
Binary_size.tag_size tag_size + length e value
(* Recursive*)
| Obj (Req {encoding = e; _}) ->
length e value
| Obj (Dft {encoding = e; _}) ->
length e value
| Tup e ->
length e value
| Conv {encoding = e; proj; _} ->
length e (proj value)
| Describe {encoding = e; _} ->
length e value
| Splitted {encoding = e; _} ->
length e value
| Dynamic_size {kind; encoding = e} ->
let length = length e value in
Binary_size.integer_to_size kind + length
| Check_size {limit; encoding = e} ->
let length = length e value in
if length > limit then raise (Write_error Size_limit_exceeded) ;
length
| Delayed f ->
length (f ()) value
let fixed_length e =
match Encoding.classify e with
| `Fixed n ->
Some n
| `Dynamic | `Variable ->
None
let rec maximum_length : type a. a Encoding.t -> int option =
fun e ->
let ( >>? ) = Option.bind in
let ( >|? ) x f = Option.map f x in
let open Encoding in
match e.encoding with
(* Fixed *)
| Null ->
Some 0
| Empty ->
Some 0
| Constant _ ->
Some 0
| Bool ->
Some Binary_size.bool
| Int8 ->
Some Binary_size.int8
| Uint8 ->
Some Binary_size.uint8
| Int16 ->
Some Binary_size.int16
| Uint16 ->
Some Binary_size.uint16
| Int31 ->
Some Binary_size.int31
| Int32 ->
Some Binary_size.int32
| Int64 ->
Some Binary_size.int64
| N ->
None
| Z ->
None
| RangedInt {minimum; maximum} ->
Some
( Binary_size.integer_to_size
@@ Binary_size.range_to_size ~minimum ~maximum )
| Float ->
Some Binary_size.float
| RangedFloat _ ->
Some Binary_size.float
| Bytes (`Fixed n) ->
Some n
| String (`Fixed n) ->
Some n
| Padded (e, n) ->
maximum_length e >|? fun s -> s + n
| String_enum (_, arr) ->
Some (Binary_size.integer_to_size @@ Binary_size.enum_size arr)
| Objs {kind = `Fixed n; _} ->
Some n
| Tups {kind = `Fixed n; _} ->
Some n
| Union {kind = `Fixed n; _} ->
Some n
(* Dynamic *)
| Obj (Opt {kind = `Dynamic; encoding = e; _}) ->
maximum_length e >|? fun s -> s + Binary_size.uint8
(* Variable *)
| Ignore ->
Some 0
| Bytes `Variable ->
None
| String `Variable ->
None
| Array (Some max_length, e) ->
maximum_length e >|? fun s -> s * max_length
| Array (None, _) ->
None
| List (Some max_length, e) ->
maximum_length e >|? fun s -> s * max_length
| List (None, _) ->
None
| Obj (Opt {kind = `Variable; encoding = e; _}) ->
maximum_length e
(* Variable or Dynamic we don't care for those constructors *)
| Union {kind = `Dynamic | `Variable; tag_size; cases; _} ->
List.fold_left
(fun acc (Case {encoding = e; _}) ->
acc >>? fun acc -> maximum_length e >|? fun s -> Stdlib.max acc s)
(Some 0)
cases
>|? fun s -> s + Binary_size.tag_size tag_size
| Objs {kind = `Dynamic | `Variable; left; right} ->
maximum_length left >>? fun l -> maximum_length right >|? fun r -> l + r
| Tups {kind = `Dynamic | `Variable; left; right} ->
maximum_length left >>? fun l -> maximum_length right >|? fun r -> l + r
| Mu _ ->
(* There could be bounded-size uses of Mu but it's unreasonable to expect
to detect them statically this way. Use `check_size` around the mu to
translate user-invariants into static encoding invariants *)
None
(* Recursive*)
| Obj (Req {encoding = e; _}) ->
maximum_length e
| Obj (Dft {encoding = e; _}) ->
maximum_length e
| Tup e ->
maximum_length e
| Conv {encoding = e; _} ->
maximum_length e
| Describe {encoding = e; _} ->
maximum_length e
| Splitted {encoding = e; _} ->
maximum_length e
| Dynamic_size {kind; encoding = e} ->
maximum_length e >|? fun s -> s + Binary_size.integer_to_size kind
| Check_size {limit; encoding = e} ->
(* NOTE: it is possible that the statically-provable maximum size exceeds
the dynamically checked limit. But the difference might be explained by
subtle invariants that do not appear in the encoding. *)
Some
(Option.fold
(maximum_length e)
~some:(fun s -> min s limit)
~none:limit)
| Delayed f ->
maximum_length (f ())