diff options
| -rw-r--r-- | src/cow_uri.erl | 214 |
1 files changed, 104 insertions, 110 deletions
diff --git a/src/cow_uri.erl b/src/cow_uri.erl index 4480d6b..4a50240 100644 --- a/src/cow_uri.erl +++ b/src/cow_uri.erl @@ -1,4 +1,4 @@ -%% Copyright (c) 2016-2023, Loïc Hoguin <[email protected]> +%% Copyright (c) 2016-2024, Loïc Hoguin <[email protected]> %% %% Permission to use, copy, modify, and/or distribute this software for any %% purpose with or without fee is hereby granted, provided that the above @@ -14,121 +14,103 @@ -module(cow_uri). +-include("cow_inline.hrl"). + -export([urldecode/1]). -export([urlencode/1]). -%% @doc Decode a percent encoded string. (RFC3986 2.1) +%% Decode a percent encoded string. (RFC3986 2.1) +%% +%% Inspiration for some of the optimisations done here come +%% from the new `json` module as it was in mid-2024. +%% +%% Possible input includes: +%% +%% * nothing encoded (no % character): +%% We want to return the binary as-is to avoid an allocation. +%% +%% * small number of encoded characters: +%% We can "skip" words of text. +%% +%% * mostly encoded characters (non-ascii languages) +%% We can decode characters in bulk. + +-define(IS_PLAIN(C), ( + (C =:= $!) orelse (C =:= $$) orelse (C =:= $&) orelse (C =:= $') orelse + (C =:= $() orelse (C =:= $)) orelse (C =:= $*) orelse (C =:= $+) orelse + (C =:= $,) orelse (C =:= $-) orelse (C =:= $.) orelse (C =:= $0) orelse + (C =:= $1) orelse (C =:= $2) orelse (C =:= $3) orelse (C =:= $4) orelse + (C =:= $5) orelse (C =:= $6) orelse (C =:= $7) orelse (C =:= $8) orelse + (C =:= $9) orelse (C =:= $:) orelse (C =:= $;) orelse (C =:= $=) orelse + (C =:= $@) orelse (C =:= $A) orelse (C =:= $B) orelse (C =:= $C) orelse + (C =:= $D) orelse (C =:= $E) orelse (C =:= $F) orelse (C =:= $G) orelse + (C =:= $H) orelse (C =:= $I) orelse (C =:= $J) orelse (C =:= $K) orelse + (C =:= $L) orelse (C =:= $M) orelse (C =:= $N) orelse (C =:= $O) orelse + (C =:= $P) orelse (C =:= $Q) orelse (C =:= $R) orelse (C =:= $S) orelse + (C =:= $T) orelse (C =:= $U) orelse (C =:= $V) orelse (C =:= $W) orelse + (C =:= $X) orelse (C =:= $Y) orelse (C =:= $Z) orelse (C =:= $_) orelse + (C =:= $a) orelse (C =:= $b) orelse (C =:= $c) orelse (C =:= $d) orelse + (C =:= $e) orelse (C =:= $f) orelse (C =:= $g) orelse (C =:= $h) orelse + (C =:= $i) orelse (C =:= $j) orelse (C =:= $k) orelse (C =:= $l) orelse + (C =:= $m) orelse (C =:= $n) orelse (C =:= $o) orelse (C =:= $p) orelse + (C =:= $q) orelse (C =:= $r) orelse (C =:= $s) orelse (C =:= $t) orelse + (C =:= $u) orelse (C =:= $v) orelse (C =:= $w) orelse (C =:= $x) orelse + (C =:= $y) orelse (C =:= $z) orelse (C =:= $~) +)). --spec urldecode(B) -> B when B::binary(). -urldecode(B) -> - urldecode(B, <<>>). +urldecode(Binary) -> + skip_dec(Binary, Binary, 0). -urldecode(<< $%, H, L, Rest/bits >>, Acc) -> - C = (unhex(H) bsl 4 bor unhex(L)), - urldecode(Rest, << Acc/bits, C >>); -urldecode(<< $!, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $! >>); -urldecode(<< $$, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $$ >>); -urldecode(<< $&, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $& >>); -urldecode(<< $', Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $' >>); -urldecode(<< $(, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $( >>); -urldecode(<< $), Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $) >>); -urldecode(<< $*, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $* >>); -urldecode(<< $+, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $+ >>); -urldecode(<< $,, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $, >>); -urldecode(<< $-, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $- >>); -urldecode(<< $., Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $. >>); -urldecode(<< $0, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $0 >>); -urldecode(<< $1, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $1 >>); -urldecode(<< $2, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $2 >>); -urldecode(<< $3, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $3 >>); -urldecode(<< $4, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $4 >>); -urldecode(<< $5, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $5 >>); -urldecode(<< $6, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $6 >>); -urldecode(<< $7, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $7 >>); -urldecode(<< $8, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $8 >>); -urldecode(<< $9, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $9 >>); -urldecode(<< $:, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $: >>); -urldecode(<< $;, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $; >>); -urldecode(<< $=, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $= >>); -urldecode(<< $@, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $@ >>); -urldecode(<< $A, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $A >>); -urldecode(<< $B, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $B >>); -urldecode(<< $C, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $C >>); -urldecode(<< $D, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $D >>); -urldecode(<< $E, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $E >>); -urldecode(<< $F, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $F >>); -urldecode(<< $G, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $G >>); -urldecode(<< $H, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $H >>); -urldecode(<< $I, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $I >>); -urldecode(<< $J, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $J >>); -urldecode(<< $K, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $K >>); -urldecode(<< $L, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $L >>); -urldecode(<< $M, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $M >>); -urldecode(<< $N, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $N >>); -urldecode(<< $O, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $O >>); -urldecode(<< $P, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $P >>); -urldecode(<< $Q, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $Q >>); -urldecode(<< $R, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $R >>); -urldecode(<< $S, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $S >>); -urldecode(<< $T, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $T >>); -urldecode(<< $U, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $U >>); -urldecode(<< $V, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $V >>); -urldecode(<< $W, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $W >>); -urldecode(<< $X, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $X >>); -urldecode(<< $Y, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $Y >>); -urldecode(<< $Z, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $Z >>); -urldecode(<< $_, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $_ >>); -urldecode(<< $a, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $a >>); -urldecode(<< $b, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $b >>); -urldecode(<< $c, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $c >>); -urldecode(<< $d, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $d >>); -urldecode(<< $e, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $e >>); -urldecode(<< $f, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $f >>); -urldecode(<< $g, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $g >>); -urldecode(<< $h, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $h >>); -urldecode(<< $i, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $i >>); -urldecode(<< $j, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $j >>); -urldecode(<< $k, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $k >>); -urldecode(<< $l, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $l >>); -urldecode(<< $m, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $m >>); -urldecode(<< $n, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $n >>); -urldecode(<< $o, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $o >>); -urldecode(<< $p, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $p >>); -urldecode(<< $q, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $q >>); -urldecode(<< $r, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $r >>); -urldecode(<< $s, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $s >>); -urldecode(<< $t, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $t >>); -urldecode(<< $u, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $u >>); -urldecode(<< $v, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $v >>); -urldecode(<< $w, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $w >>); -urldecode(<< $x, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $x >>); -urldecode(<< $y, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $y >>); -urldecode(<< $z, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $z >>); -urldecode(<< $~, Rest/bits >>, Acc) -> urldecode(Rest, << Acc/bits, $~ >>); -urldecode(<<>>, Acc) -> Acc. +%% This functions helps avoid a binary allocation when +%% there is nothing to decode. +skip_dec(Binary, Orig, Len) -> + case Binary of + <<C1, C2, C3, C4, Rest/bits>> + when ?IS_PLAIN(C1) andalso ?IS_PLAIN(C2) + andalso ?IS_PLAIN(C3) andalso ?IS_PLAIN(C4) -> + skip_dec(Rest, Orig, Len + 4); + _ -> + dec(Binary, [], Orig, 0, Len) + end. -unhex($0) -> 0; -unhex($1) -> 1; -unhex($2) -> 2; -unhex($3) -> 3; -unhex($4) -> 4; -unhex($5) -> 5; -unhex($6) -> 6; -unhex($7) -> 7; -unhex($8) -> 8; -unhex($9) -> 9; -unhex($A) -> 10; -unhex($B) -> 11; -unhex($C) -> 12; -unhex($D) -> 13; -unhex($E) -> 14; -unhex($F) -> 15; -unhex($a) -> 10; -unhex($b) -> 11; -unhex($c) -> 12; -unhex($d) -> 13; -unhex($e) -> 14; -unhex($f) -> 15. +%% This clause helps speed up decoding of highly encoded values. +dec(<<$%, H1, L1, $%, H2, L2, $%, H3, L3, $%, H4, L4, Rest/bits>>, Acc, Orig, Skip, Len) -> + C1 = ?UNHEX(H1, L1), + C2 = ?UNHEX(H2, L2), + C3 = ?UNHEX(H3, L3), + C4 = ?UNHEX(H4, L4), + case Len of + 0 -> + dec(Rest, [Acc|<<C1, C2, C3, C4>>], Orig, Skip + 12, 0); + _ -> + Part = binary_part(Orig, Skip, Len), + dec(Rest, [Acc, Part|<<C1, C2, C3, C4>>], Orig, Skip + Len + 12, 0) + end; +dec(<<$%, H, L, Rest/bits>>, Acc, Orig, Skip, Len) -> + C = ?UNHEX(H, L), + case Len of + 0 -> + dec(Rest, [Acc|<<C>>], Orig, Skip + 3, 0); + _ -> + Part = binary_part(Orig, Skip, Len), + dec(Rest, [Acc, Part|<<C>>], Orig, Skip + Len + 3, 0) + end; +%% This clause helps speed up decoding of barely encoded values. +dec(<<C1, C2, C3, C4, Rest/bits>>, Acc, Orig, Skip, Len) + when ?IS_PLAIN(C1) andalso ?IS_PLAIN(C2) + andalso ?IS_PLAIN(C3) andalso ?IS_PLAIN(C4) -> + dec(Rest, Acc, Orig, Skip, Len + 4); +dec(<<C, Rest/bits>>, Acc, Orig, Skip, Len) when ?IS_PLAIN(C) -> + dec(Rest, Acc, Orig, Skip, Len + 1); +dec(<<>>, _, Orig, 0, _) -> + Orig; +dec(<<>>, Acc, _, _, 0) -> + iolist_to_binary(Acc); +dec(<<>>, Acc, Orig, Skip, Len) -> + Part = binary_part(Orig, Skip, Len), + iolist_to_binary([Acc|Part]); +dec(_, _, Orig, Skip, Len) -> + error({invalid_byte, binary:at(Orig, Skip + Len)}). -ifdef(TEST). urldecode_test_() -> @@ -179,6 +161,18 @@ horse_urldecode_jp_hex() -> "%AB%E3%80%9C%E8%BC%AA%E5%BB%BB%E3%81%99%E3%82%8B%E6%97%8B%E5" "%BE%8B%E3%80%9C">>) ). + +horse_urldecode_jp_mixed_hex() -> + horse:repeat(100000, + urldecode(<<"%E3%83%84%E3%82%A4%E3%83%B3%E3%82%BD%E3123%82%A6%E3%83" + "%AB%E3%80%9C%E8%BC%AA%E5%BB%BB%E3%81%99%E3%82%8B%E6%97%8B%E5" + "%BE%8B%E3%80%9C">>) + ). + +horse_urldecode_worst_case_hex() -> + horse:repeat(100000, + urldecode(<<"%e3%83123%84%e3123%82%a4123%e3%83123%b3%e3123%82%bd123">>) + ). -endif. %% @doc Percent encode a string. (RFC3986 2.1) |