%% Copyright (c) 2011-2017, Loïc Hoguin %% %% Permission to use, copy, modify, and/or distribute this software for any %% purpose with or without fee is hereby granted, provided that the above %% copyright notice and this permission notice appear in all copies. %% %% THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES %% WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF %% MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR %% ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES %% WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN %% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF %% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. -module(cowboy_bstr). %% Binary strings. -export([capitalize_token/1]). -export([to_lower/1]). -export([to_upper/1]). %% Characters. -export([char_to_lower/1]). -export([char_to_upper/1]). %% The first letter and all letters after a dash are capitalized. %% This is the form seen for header names in the HTTP/1.1 RFC and %% others. Note that using this form isn't required, as header names %% are case insensitive, and it is only provided for use with eventual %% badly implemented clients. -spec capitalize_token(B) -> B when B::binary(). capitalize_token(B) -> capitalize_token(B, true, <<>>). capitalize_token(<<>>, _, Acc) -> Acc; capitalize_token(<< $-, Rest/bits >>, _, Acc) -> capitalize_token(Rest, true, << Acc/binary, $- >>); capitalize_token(<< C, Rest/bits >>, true, Acc) -> capitalize_token(Rest, false, << Acc/binary, (char_to_upper(C)) >>); capitalize_token(<< C, Rest/bits >>, false, Acc) -> capitalize_token(Rest, false, << Acc/binary, (char_to_lower(C)) >>). -spec to_lower(B) -> B when B::binary(). to_lower(B) -> << << (char_to_lower(C)) >> || << C >> <= B >>. -spec to_upper(B) -> B when B::binary(). to_upper(B) -> << << (char_to_upper(C)) >> || << C >> <= B >>. -spec char_to_lower(char()) -> char(). char_to_lower($A) -> $a; char_to_lower($B) -> $b; char_to_lower($C) -> $c; char_to_lower($D) -> $d; char_to_lower($E) -> $e; char_to_lower($F) -> $f; char_to_lower($G) -> $g; char_to_lower($H) -> $h; char_to_lower($I) -> $i; char_to_lower($J) -> $j; char_to_lower($K) -> $k; char_to_lower($L) -> $l; char_to_lower($M) -> $m; char_to_lower($N) -> $n; char_to_lower($O) -> $o; char_to_lower($P) -> $p; char_to_lower($Q) -> $q; char_to_lower($R) -> $r; char_to_lower($S) -> $s; char_to_lower($T) -> $t; char_to_lower($U) -> $u; char_to_lower($V) -> $v; char_to_lower($W) -> $w; char_to_lower($X) -> $x; char_to_lower($Y) -> $y; char_to_lower($Z) -> $z; char_to_lower(Ch) -> Ch. -spec char_to_upper(char()) -> char(). char_to_upper($a) -> $A; char_to_upper($b) -> $B; char_to_upper($c) -> $C; char_to_upper($d) -> $D; char_to_upper($e) -> $E; char_to_upper($f) -> $F; char_to_upper($g) -> $G; char_to_upper($h) -> $H; char_to_upper($i) -> $I; char_to_upper($j) -> $J; char_to_upper($k) -> $K; char_to_upper($l) -> $L; char_to_upper($m) -> $M; char_to_upper($n) -> $N; char_to_upper($o) -> $O; char_to_upper($p) -> $P; char_to_upper($q) -> $Q; char_to_upper($r) -> $R; char_to_upper($s) -> $S; char_to_upper($t) -> $T; char_to_upper($u) -> $U; char_to_upper($v) -> $V; char_to_upper($w) -> $W; char_to_upper($x) -> $X; char_to_upper($y) -> $Y; char_to_upper($z) -> $Z; char_to_upper(Ch) -> Ch. %% Tests. -ifdef(TEST). capitalize_token_test_() -> Tests = [ {<<"heLLo-woRld">>, <<"Hello-World">>}, {<<"Sec-Websocket-Version">>, <<"Sec-Websocket-Version">>}, {<<"Sec-WebSocket-Version">>, <<"Sec-Websocket-Version">>}, {<<"sec-websocket-version">>, <<"Sec-Websocket-Version">>}, {<<"SEC-WEBSOCKET-VERSION">>, <<"Sec-Websocket-Version">>}, {<<"Sec-WebSocket--Version">>, <<"Sec-Websocket--Version">>}, {<<"Sec-WebSocket---Version">>, <<"Sec-Websocket---Version">>} ], [{H, fun() -> R = capitalize_token(H) end} || {H, R} <- Tests]. -endif.