flm01/server/api/webmachine/deps/mochiweb/src/mochiweb_html.erl

894 lines
33 KiB
Erlang

%% @author Bob Ippolito <bob@mochimedia.com>
%% @copyright 2007 Mochi Media, Inc.
%% @doc Loosely tokenizes and generates parse trees for HTML 4.
-module(mochiweb_html).
-export([tokens/1, parse/1, parse_tokens/1, to_tokens/1, escape/1,
escape_attr/1, to_html/1, test/0]).
% This is a macro to placate syntax highlighters..
-define(QUOTE, $\").
-define(SQUOTE, $\').
-define(ADV_COL(S, N),
S#decoder{column=N+S#decoder.column,
offset=N+S#decoder.offset}).
-define(INC_COL(S),
S#decoder{column=1+S#decoder.column,
offset=1+S#decoder.offset}).
-define(INC_LINE(S),
S#decoder{column=1,
line=1+S#decoder.line,
offset=1+S#decoder.offset}).
-define(INC_CHAR(S, C),
case C of
$\n ->
S#decoder{column=1,
line=1+S#decoder.line,
offset=1+S#decoder.offset};
_ ->
S#decoder{column=1+S#decoder.column,
offset=1+S#decoder.offset}
end).
-define(IS_WHITESPACE(C),
(C =:= $\s orelse C =:= $\t orelse C =:= $\r orelse C =:= $\n)).
-define(IS_LITERAL_SAFE(C),
((C >= $A andalso C =< $Z) orelse (C >= $a andalso C =< $z)
orelse (C >= $0 andalso C =< $9))).
-record(decoder, {line=1,
column=1,
offset=0}).
%% @type html_node() = {string(), [html_attr()], [html_node() | string()]}
%% @type html_attr() = {string(), string()}
%% @type html_token() = html_data() | start_tag() | end_tag() | inline_html() | html_comment() | html_doctype()
%% @type html_data() = {data, string(), Whitespace::boolean()}
%% @type start_tag() = {start_tag, Name, [html_attr()], Singleton::boolean()}
%% @type end_tag() = {end_tag, Name}
%% @type html_comment() = {comment, Comment}
%% @type html_doctype() = {doctype, [Doctype]}
%% @type inline_html() = {'=', iolist()}
%% External API.
%% @spec parse(string() | binary()) -> html_node()
%% @doc tokenize and then transform the token stream into a HTML tree.
parse(Input) ->
parse_tokens(tokens(Input)).
%% @spec parse_tokens([html_token()]) -> html_node()
%% @doc Transform the output of tokens(Doc) into a HTML tree.
parse_tokens(Tokens) when is_list(Tokens) ->
%% Skip over doctype, processing instructions
F = fun (X) ->
case X of
{start_tag, _, _, false} ->
false;
_ ->
true
end
end,
[{start_tag, Tag, Attrs, false} | Rest] = lists:dropwhile(F, Tokens),
{Tree, _} = tree(Rest, [norm({Tag, Attrs})]),
Tree.
%% @spec tokens(StringOrBinary) -> [html_token()]
%% @doc Transform the input UTF-8 HTML into a token stream.
tokens(Input) ->
tokens(iolist_to_binary(Input), #decoder{}, []).
%% @spec to_tokens(html_node()) -> [html_token()]
%% @doc Convert a html_node() tree to a list of tokens.
to_tokens({Tag0}) ->
to_tokens({Tag0, [], []});
to_tokens(T={'=', _}) ->
[T];
to_tokens(T={doctype, _}) ->
[T];
to_tokens(T={comment, _}) ->
[T];
to_tokens({Tag0, Acc}) ->
to_tokens({Tag0, [], Acc});
to_tokens({Tag0, Attrs, Acc}) ->
Tag = to_tag(Tag0),
to_tokens([{Tag, Acc}], [{start_tag, Tag, Attrs, is_singleton(Tag)}]).
%% @spec to_html([html_token()] | html_node()) -> iolist()
%% @doc Convert a list of html_token() to a HTML document.
to_html(Node) when is_tuple(Node) ->
to_html(to_tokens(Node));
to_html(Tokens) when is_list(Tokens) ->
to_html(Tokens, []).
%% @spec escape(string() | atom() | binary()) -> binary()
%% @doc Escape a string such that it's safe for HTML (amp; lt; gt;).
escape(B) when is_binary(B) ->
escape(binary_to_list(B), []);
escape(A) when is_atom(A) ->
escape(atom_to_list(A), []);
escape(S) when is_list(S) ->
escape(S, []).
%% @spec escape_attr(string() | binary() | atom() | integer() | float()) -> binary()
%% @doc Escape a string such that it's safe for HTML attrs
%% (amp; lt; gt; quot;).
escape_attr(B) when is_binary(B) ->
escape_attr(binary_to_list(B), []);
escape_attr(A) when is_atom(A) ->
escape_attr(atom_to_list(A), []);
escape_attr(S) when is_list(S) ->
escape_attr(S, []);
escape_attr(I) when is_integer(I) ->
escape_attr(integer_to_list(I), []);
escape_attr(F) when is_float(F) ->
escape_attr(mochinum:digits(F), []).
%% @spec test() -> ok
%% @doc Run tests for mochiweb_html.
test() ->
test_destack(),
test_tokens(),
test_tokens2(),
test_parse(),
test_parse2(),
test_parse_tokens(),
test_escape(),
test_escape_attr(),
test_to_html(),
ok.
%% Internal API
test_to_html() ->
Expect = <<"<html><head><title>hey!</title></head><body><p class=\"foo\">what's up<br /></p><div>sucka</div><!-- comment! --></body></html>">>,
Expect = iolist_to_binary(
to_html({html, [],
[{<<"head">>, [],
[{title, <<"hey!">>}]},
{body, [],
[{p, [{class, foo}], [<<"what's">>, <<" up">>, {br}]},
{'div', <<"sucka">>},
{comment, <<" comment! ">>}]}]})),
Expect1 = <<"<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\" \"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">">>,
Expect1 = iolist_to_binary(
to_html({doctype,
[<<"html">>, <<"PUBLIC">>,
<<"-//W3C//DTD XHTML 1.0 Transitional//EN">>,
<<"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">>]})),
ok.
to_html([], Acc) ->
lists:reverse(Acc);
to_html([{'=', Content} | Rest], Acc) ->
to_html(Rest, [Content | Acc]);
to_html([{pi, Tag, Attrs} | Rest], Acc) ->
Open = [<<"<?">>,
Tag,
attrs_to_html(Attrs, []),
<<"?>">>],
to_html(Rest, [Open | Acc]);
to_html([{comment, Comment} | Rest], Acc) ->
to_html(Rest, [[<<"<!--">>, Comment, <<"-->">>] | Acc]);
to_html([{doctype, Parts} | Rest], Acc) ->
Inside = doctype_to_html(Parts, Acc),
to_html(Rest, [[<<"<!DOCTYPE">>, Inside, <<">">>] | Acc]);
to_html([{data, Data, _Whitespace} | Rest], Acc) ->
to_html(Rest, [escape(Data) | Acc]);
to_html([{start_tag, Tag, Attrs, Singleton} | Rest], Acc) ->
Open = [<<"<">>,
Tag,
attrs_to_html(Attrs, []),
case Singleton of
true -> <<" />">>;
false -> <<">">>
end],
to_html(Rest, [Open | Acc]);
to_html([{end_tag, Tag} | Rest], Acc) ->
to_html(Rest, [[<<"</">>, Tag, <<">">>] | Acc]).
doctype_to_html([], Acc) ->
lists:reverse(Acc);
doctype_to_html([Word | Rest], Acc) ->
case lists:all(fun (C) -> ?IS_LITERAL_SAFE(C) end,
binary_to_list(iolist_to_binary(Word))) of
true ->
doctype_to_html(Rest, [[<<" ">>, Word] | Acc]);
false ->
doctype_to_html(Rest, [[<<" \"">>, escape_attr(Word), ?QUOTE] | Acc])
end.
attrs_to_html([], Acc) ->
lists:reverse(Acc);
attrs_to_html([{K, V} | Rest], Acc) ->
attrs_to_html(Rest,
[[<<" ">>, escape(K), <<"=\"">>,
escape_attr(V), <<"\"">>] | Acc]).
test_escape() ->
<<"&amp;quot;\"word &lt;&lt;up!&amp;quot;">> =
escape(<<"&quot;\"word <<up!&quot;">>),
ok.
test_escape_attr() ->
<<"&amp;quot;&quot;word &lt;&lt;up!&amp;quot;">> =
escape_attr(<<"&quot;\"word <<up!&quot;">>),
ok.
escape([], Acc) ->
list_to_binary(lists:reverse(Acc));
escape("<" ++ Rest, Acc) ->
escape(Rest, lists:reverse("&lt;", Acc));
escape(">" ++ Rest, Acc) ->
escape(Rest, lists:reverse("&gt;", Acc));
escape("&" ++ Rest, Acc) ->
escape(Rest, lists:reverse("&amp;", Acc));
escape([C | Rest], Acc) ->
escape(Rest, [C | Acc]).
escape_attr([], Acc) ->
list_to_binary(lists:reverse(Acc));
escape_attr("<" ++ Rest, Acc) ->
escape_attr(Rest, lists:reverse("&lt;", Acc));
escape_attr(">" ++ Rest, Acc) ->
escape_attr(Rest, lists:reverse("&gt;", Acc));
escape_attr("&" ++ Rest, Acc) ->
escape_attr(Rest, lists:reverse("&amp;", Acc));
escape_attr([?QUOTE | Rest], Acc) ->
escape_attr(Rest, lists:reverse("&quot;", Acc));
escape_attr([C | Rest], Acc) ->
escape_attr(Rest, [C | Acc]).
to_tag(A) when is_atom(A) ->
norm(atom_to_list(A));
to_tag(L) ->
norm(L).
to_tokens([], Acc) ->
lists:reverse(Acc);
to_tokens([{Tag, []} | Rest], Acc) ->
to_tokens(Rest, [{end_tag, to_tag(Tag)} | Acc]);
to_tokens([{Tag0, [{T0} | R1]} | Rest], Acc) ->
%% Allow {br}
to_tokens([{Tag0, [{T0, [], []} | R1]} | Rest], Acc);
to_tokens([{Tag0, [T0={'=', _C0} | R1]} | Rest], Acc) ->
%% Allow {'=', iolist()}
to_tokens([{Tag0, R1} | Rest], [T0 | Acc]);
to_tokens([{Tag0, [T0={comment, _C0} | R1]} | Rest], Acc) ->
%% Allow {comment, iolist()}
to_tokens([{Tag0, R1} | Rest], [T0 | Acc]);
to_tokens([{Tag0, [{T0, A0=[{_, _} | _]} | R1]} | Rest], Acc) ->
%% Allow {p, [{"class", "foo"}]}
to_tokens([{Tag0, [{T0, A0, []} | R1]} | Rest], Acc);
to_tokens([{Tag0, [{T0, C0} | R1]} | Rest], Acc) ->
%% Allow {p, "content"} and {p, <<"content">>}
to_tokens([{Tag0, [{T0, [], C0} | R1]} | Rest], Acc);
to_tokens([{Tag0, [{T0, A1, C0} | R1]} | Rest], Acc) when is_binary(C0) ->
%% Allow {"p", [{"class", "foo"}], <<"content">>}
to_tokens([{Tag0, [{T0, A1, binary_to_list(C0)} | R1]} | Rest], Acc);
to_tokens([{Tag0, [{T0, A1, C0=[C | _]} | R1]} | Rest], Acc)
when is_integer(C) ->
%% Allow {"p", [{"class", "foo"}], "content"}
to_tokens([{Tag0, [{T0, A1, [C0]} | R1]} | Rest], Acc);
to_tokens([{Tag0, [{T0, A1, C1} | R1]} | Rest], Acc) ->
%% Native {"p", [{"class", "foo"}], ["content"]}
Tag = to_tag(Tag0),
T1 = to_tag(T0),
case is_singleton(norm(T1)) of
true ->
to_tokens([{Tag, R1} | Rest], [{start_tag, T1, A1, true} | Acc]);
false ->
to_tokens([{T1, C1}, {Tag, R1} | Rest],
[{start_tag, T1, A1, false} | Acc])
end;
to_tokens([{Tag0, [L | R1]} | Rest], Acc) when is_list(L) ->
%% List text
Tag = to_tag(Tag0),
to_tokens([{Tag, R1} | Rest], [{data, iolist_to_binary(L), false} | Acc]);
to_tokens([{Tag0, [B | R1]} | Rest], Acc) when is_binary(B) ->
%% Binary text
Tag = to_tag(Tag0),
to_tokens([{Tag, R1} | Rest], [{data, B, false} | Acc]).
test_tokens() ->
[{start_tag, <<"foo">>, [{<<"bar">>, <<"baz">>},
{<<"wibble">>, <<"wibble">>},
{<<"alice">>, <<"bob">>}], true}] =
tokens(<<"<foo bar=baz wibble='wibble' alice=\"bob\"/>">>),
[{start_tag, <<"foo">>, [{<<"bar">>, <<"baz">>},
{<<"wibble">>, <<"wibble">>},
{<<"alice">>, <<"bob">>}], true}] =
tokens(<<"<foo bar=baz wibble='wibble' alice=bob/>">>),
[{comment, <<"[if lt IE 7]>\n<style type=\"text/css\">\n.no_ie { display: none; }\n</style>\n<![endif]">>}] =
tokens(<<"<!--[if lt IE 7]>\n<style type=\"text/css\">\n.no_ie { display: none; }\n</style>\n<![endif]-->">>),
[{start_tag, <<"script">>, [{<<"type">>, <<"text/javascript">>}], false},
{data, <<" A= B <= C ">>, false},
{end_tag, <<"script">>}] =
tokens(<<"<script type=\"text/javascript\"> A= B <= C </script>">>),
[{start_tag, <<"script">>, [{<<"type">>, <<"text/javascript">>}], false},
{data, <<" A= B <= C ">>, false},
{end_tag, <<"script">>}] =
tokens(<<"<script type =\"text/javascript\"> A= B <= C </script>">>),
[{start_tag, <<"script">>, [{<<"type">>, <<"text/javascript">>}], false},
{data, <<" A= B <= C ">>, false},
{end_tag, <<"script">>}] =
tokens(<<"<script type = \"text/javascript\"> A= B <= C </script>">>),
[{start_tag, <<"script">>, [{<<"type">>, <<"text/javascript">>}], false},
{data, <<" A= B <= C ">>, false},
{end_tag, <<"script">>}] =
tokens(<<"<script type= \"text/javascript\"> A= B <= C </script>">>),
[{start_tag, <<"textarea">>, [], false},
{data, <<"<html></body>">>, false},
{end_tag, <<"textarea">>}] =
tokens(<<"<textarea><html></body></textarea>">>),
ok.
tokens(B, S=#decoder{offset=O}, Acc) ->
case B of
<<_:O/binary>> ->
lists:reverse(Acc);
_ ->
{Tag, S1} = tokenize(B, S),
case parse_flag(Tag) of
script ->
{Tag2, S2} = tokenize_script(B, S1),
tokens(B, S2, [Tag2, Tag | Acc]);
textarea ->
{Tag2, S2} = tokenize_textarea(B, S1),
tokens(B, S2, [Tag2, Tag | Acc]);
none ->
tokens(B, S1, [Tag | Acc])
end
end.
parse_flag({start_tag, B, _, false}) ->
case string:to_lower(binary_to_list(B)) of
"script" ->
script;
"textarea" ->
textarea;
_ ->
none
end;
parse_flag(_) ->
none.
tokenize(B, S=#decoder{offset=O}) ->
case B of
<<_:O/binary, "<!--", _/binary>> ->
tokenize_comment(B, ?ADV_COL(S, 4));
<<_:O/binary, "<!DOCTYPE", _/binary>> ->
tokenize_doctype(B, ?ADV_COL(S, 10));
<<_:O/binary, "<![CDATA[", _/binary>> ->
tokenize_cdata(B, ?ADV_COL(S, 9));
<<_:O/binary, "<?", _/binary>> ->
{Tag, S1} = tokenize_literal(B, ?ADV_COL(S, 2)),
{Attrs, S2} = tokenize_attributes(B, S1),
S3 = find_qgt(B, S2),
{{pi, Tag, Attrs}, S3};
<<_:O/binary, "&", _/binary>> ->
tokenize_charref(B, ?INC_COL(S));
<<_:O/binary, "</", _/binary>> ->
{Tag, S1} = tokenize_literal(B, ?ADV_COL(S, 2)),
{S2, _} = find_gt(B, S1),
{{end_tag, Tag}, S2};
<<_:O/binary, "<", C, _/binary>> when ?IS_WHITESPACE(C) ->
%% This isn't really strict HTML
tokenize_data(B, ?INC_COL(S));
<<_:O/binary, "<", _/binary>> ->
{Tag, S1} = tokenize_literal(B, ?INC_COL(S)),
{Attrs, S2} = tokenize_attributes(B, S1),
{S3, HasSlash} = find_gt(B, S2),
Singleton = HasSlash orelse is_singleton(norm(binary_to_list(Tag))),
{{start_tag, Tag, Attrs, Singleton}, S3};
_ ->
tokenize_data(B, S)
end.
test_parse() ->
D0 = <<"<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01//EN\" \"http://www.w3.org/TR/html4/strict.dtd\">
<html>
<head>
<meta http-equiv=\"Content-Type\" content=\"text/html; charset=UTF-8\">
<title>Foo</title>
<link rel=\"stylesheet\" type=\"text/css\" href=\"/static/rel/dojo/resources/dojo.css\" media=\"screen\">
<link rel=\"stylesheet\" type=\"text/css\" href=\"/static/foo.css\" media=\"screen\">
<!--[if lt IE 7]>
<style type=\"text/css\">
.no_ie { display: none; }
</style>
<![endif]-->
<link rel=\"icon\" href=\"/static/images/favicon.ico\" type=\"image/x-icon\">
<link rel=\"shortcut icon\" href=\"/static/images/favicon.ico\" type=\"image/x-icon\">
</head>
<body id=\"home\" class=\"tundra\"><![CDATA[&lt;<this<!-- is -->CDATA>&gt;]]></body>
</html>">>,
Expect = {<<"html">>, [],
[{<<"head">>, [],
[{<<"meta">>,
[{<<"http-equiv">>,<<"Content-Type">>},
{<<"content">>,<<"text/html; charset=UTF-8">>}],
[]},
{<<"title">>,[],[<<"Foo">>]},
{<<"link">>,
[{<<"rel">>,<<"stylesheet">>},
{<<"type">>,<<"text/css">>},
{<<"href">>,<<"/static/rel/dojo/resources/dojo.css">>},
{<<"media">>,<<"screen">>}],
[]},
{<<"link">>,
[{<<"rel">>,<<"stylesheet">>},
{<<"type">>,<<"text/css">>},
{<<"href">>,<<"/static/foo.css">>},
{<<"media">>,<<"screen">>}],
[]},
{comment,<<"[if lt IE 7]>\n <style type=\"text/css\">\n .no_ie { display: none; }\n </style>\n <![endif]">>},
{<<"link">>,
[{<<"rel">>,<<"icon">>},
{<<"href">>,<<"/static/images/favicon.ico">>},
{<<"type">>,<<"image/x-icon">>}],
[]},
{<<"link">>,
[{<<"rel">>,<<"shortcut icon">>},
{<<"href">>,<<"/static/images/favicon.ico">>},
{<<"type">>,<<"image/x-icon">>}],
[]}]},
{<<"body">>,
[{<<"id">>,<<"home">>},
{<<"class">>,<<"tundra">>}],
[<<"&lt;<this<!-- is -->CDATA>&gt;">>]}]},
Expect = parse(D0),
ok.
test_tokens2() ->
D0 = <<"<channel><title>from __future__ import *</title><link>http://bob.pythonmac.org</link><description>Bob's Rants</description></channel>">>,
Expect = [{start_tag,<<"channel">>,[],false},
{start_tag,<<"title">>,[],false},
{data,<<"from __future__ import *">>,false},
{end_tag,<<"title">>},
{start_tag,<<"link">>,[],true},
{data,<<"http://bob.pythonmac.org">>,false},
{end_tag,<<"link">>},
{start_tag,<<"description">>,[],false},
{data,<<"Bob's Rants">>,false},
{end_tag,<<"description">>},
{end_tag,<<"channel">>}],
Expect = tokens(D0),
ok.
test_parse2() ->
D0 = <<"<channel><title>from __future__ import *</title><link>http://bob.pythonmac.org<br>foo</link><description>Bob's Rants</description></channel>">>,
Expect = {<<"channel">>,[],
[{<<"title">>,[],[<<"from __future__ import *">>]},
{<<"link">>,[],[
<<"http://bob.pythonmac.org">>,
{<<"br">>,[],[]},
<<"foo">>]},
{<<"description">>,[],[<<"Bob's Rants">>]}]},
Expect = parse(D0),
ok.
test_parse_tokens() ->
D0 = [{doctype,[<<"HTML">>,<<"PUBLIC">>,<<"-//W3C//DTD HTML 4.01 Transitional//EN">>]},
{data,<<"\n">>,true},
{start_tag,<<"html">>,[],false}],
{<<"html">>, [], []} = parse_tokens(D0),
D1 = D0 ++ [{end_tag, <<"html">>}],
{<<"html">>, [], []} = parse_tokens(D1),
D2 = D0 ++ [{start_tag, <<"body">>, [], false}],
{<<"html">>, [], [{<<"body">>, [], []}]} = parse_tokens(D2),
D3 = D0 ++ [{start_tag, <<"head">>, [], false},
{end_tag, <<"head">>},
{start_tag, <<"body">>, [], false}],
{<<"html">>, [], [{<<"head">>, [], []}, {<<"body">>, [], []}]} = parse_tokens(D3),
D4 = D3 ++ [{data,<<"\n">>,true},
{start_tag,<<"div">>,[{<<"class">>,<<"a">>}],false},
{start_tag,<<"a">>,[{<<"name">>,<<"#anchor">>}],false},
{end_tag,<<"a">>},
{end_tag,<<"div">>},
{start_tag,<<"div">>,[{<<"class">>,<<"b">>}],false},
{start_tag,<<"div">>,[{<<"class">>,<<"c">>}],false},
{end_tag,<<"div">>},
{end_tag,<<"div">>}],
{<<"html">>, [],
[{<<"head">>, [], []},
{<<"body">>, [],
[{<<"div">>, [{<<"class">>, <<"a">>}], [{<<"a">>, [{<<"name">>, <<"#anchor">>}], []}]},
{<<"div">>, [{<<"class">>, <<"b">>}], [{<<"div">>, [{<<"class">>, <<"c">>}], []}]}
]}]} = parse_tokens(D4),
D5 = [{start_tag,<<"html">>,[],false},
{data,<<"\n">>,true},
{data,<<"boo">>,false},
{data,<<"hoo">>,false},
{data,<<"\n">>,true},
{end_tag,<<"html">>}],
{<<"html">>, [], [<<"\nboohoo\n">>]} = parse_tokens(D5),
D6 = [{start_tag,<<"html">>,[],false},
{data,<<"\n">>,true},
{data,<<"\n">>,true},
{end_tag,<<"html">>}],
{<<"html">>, [], []} = parse_tokens(D6),
D7 = [{start_tag,<<"html">>,[],false},
{start_tag,<<"ul">>,[],false},
{start_tag,<<"li">>,[],false},
{data,<<"word">>,false},
{start_tag,<<"li">>,[],false},
{data,<<"up">>,false},
{end_tag,<<"li">>},
{start_tag,<<"li">>,[],false},
{data,<<"fdsa">>,false},
{start_tag,<<"br">>,[],true},
{data,<<"asdf">>,false},
{end_tag,<<"ul">>},
{end_tag,<<"html">>}],
{<<"html">>, [],
[{<<"ul">>, [],
[{<<"li">>, [], [<<"word">>]},
{<<"li">>, [], [<<"up">>]},
{<<"li">>, [], [<<"fdsa">>,{<<"br">>, [], []}, <<"asdf">>]}]}]} = parse_tokens(D7),
ok.
tree_data([{data, Data, Whitespace} | Rest], AllWhitespace, Acc) ->
tree_data(Rest, (Whitespace andalso AllWhitespace), [Data | Acc]);
tree_data(Rest, AllWhitespace, Acc) ->
{iolist_to_binary(lists:reverse(Acc)), AllWhitespace, Rest}.
tree([], Stack) ->
{destack(Stack), []};
tree([{end_tag, Tag} | Rest], Stack) ->
case destack(norm(Tag), Stack) of
S when is_list(S) ->
tree(Rest, S);
Result ->
{Result, []}
end;
tree([{start_tag, Tag, Attrs, true} | Rest], S) ->
tree(Rest, append_stack_child(norm({Tag, Attrs}), S));
tree([{start_tag, Tag, Attrs, false} | Rest], S) ->
tree(Rest, stack(norm({Tag, Attrs}), S));
tree([T={pi, _Tag, _Attrs} | Rest], S) ->
tree(Rest, append_stack_child(T, S));
tree([T={comment, _Comment} | Rest], S) ->
tree(Rest, append_stack_child(T, S));
tree(L=[{data, _Data, _Whitespace} | _], S) ->
case tree_data(L, true, []) of
{_, true, Rest} ->
tree(Rest, S);
{Data, false, Rest} ->
tree(Rest, append_stack_child(Data, S))
end.
norm({Tag, Attrs}) ->
{norm(Tag), [{norm(K), iolist_to_binary(V)} || {K, V} <- Attrs], []};
norm(Tag) when is_binary(Tag) ->
Tag;
norm(Tag) ->
list_to_binary(string:to_lower(Tag)).
test_destack() ->
{<<"a">>, [], []} =
destack([{<<"a">>, [], []}]),
{<<"a">>, [], [{<<"b">>, [], []}]} =
destack([{<<"b">>, [], []}, {<<"a">>, [], []}]),
{<<"a">>, [], [{<<"b">>, [], [{<<"c">>, [], []}]}]} =
destack([{<<"c">>, [], []}, {<<"b">>, [], []}, {<<"a">>, [], []}]),
[{<<"a">>, [], [{<<"b">>, [], [{<<"c">>, [], []}]}]}] =
destack(<<"b">>,
[{<<"c">>, [], []}, {<<"b">>, [], []}, {<<"a">>, [], []}]),
[{<<"b">>, [], [{<<"c">>, [], []}]}, {<<"a">>, [], []}] =
destack(<<"c">>,
[{<<"c">>, [], []}, {<<"b">>, [], []},{<<"a">>, [], []}]),
ok.
stack(T1={TN, _, _}, Stack=[{TN, _, _} | _Rest])
when TN =:= <<"li">> orelse TN =:= <<"option">> ->
[T1 | destack(TN, Stack)];
stack(T1={TN0, _, _}, Stack=[{TN1, _, _} | _Rest])
when (TN0 =:= <<"dd">> orelse TN0 =:= <<"dt">>) andalso
(TN1 =:= <<"dd">> orelse TN1 =:= <<"dt">>) ->
[T1 | destack(TN1, Stack)];
stack(T1, Stack) ->
[T1 | Stack].
append_stack_child(StartTag, [{Name, Attrs, Acc} | Stack]) ->
[{Name, Attrs, [StartTag | Acc]} | Stack].
destack(TagName, Stack) when is_list(Stack) ->
F = fun (X) ->
case X of
{TagName, _, _} ->
false;
_ ->
true
end
end,
case lists:splitwith(F, Stack) of
{_, []} ->
%% If we're parsing something like XML we might find
%% a <link>tag</link> that is normally a singleton
%% in HTML but isn't here
case {is_singleton(TagName), Stack} of
{true, [{T0, A0, Acc0} | Post0]} ->
case lists:splitwith(F, Acc0) of
{_, []} ->
%% Actually was a singleton
Stack;
{Pre, [{T1, A1, []} | Post1]} ->
[{T0, A0, [{T1, A1, lists:reverse(Pre)} | Post1]}
| Post0]
end;
_ ->
%% No match, no state change
Stack
end;
{_Pre, [_T]} ->
%% Unfurl the whole stack, we're done
destack(Stack);
{Pre, [T, {T0, A0, Acc0} | Post]} ->
%% Unfurl up to the tag, then accumulate it
[{T0, A0, [destack(Pre ++ [T]) | Acc0]} | Post]
end.
destack([{Tag, Attrs, Acc}]) ->
{Tag, Attrs, lists:reverse(Acc)};
destack([{T1, A1, Acc1}, {T0, A0, Acc0} | Rest]) ->
destack([{T0, A0, [{T1, A1, lists:reverse(Acc1)} | Acc0]} | Rest]).
is_singleton(<<"br">>) -> true;
is_singleton(<<"hr">>) -> true;
is_singleton(<<"img">>) -> true;
is_singleton(<<"input">>) -> true;
is_singleton(<<"base">>) -> true;
is_singleton(<<"meta">>) -> true;
is_singleton(<<"link">>) -> true;
is_singleton(<<"area">>) -> true;
is_singleton(<<"param">>) -> true;
is_singleton(<<"col">>) -> true;
is_singleton(_) -> false.
tokenize_data(B, S=#decoder{offset=O}) ->
tokenize_data(B, S, O, true).
tokenize_data(B, S=#decoder{offset=O}, Start, Whitespace) ->
case B of
<<_:O/binary, C, _/binary>> when (C =/= $< andalso C =/= $&) ->
tokenize_data(B, ?INC_CHAR(S, C), Start,
(Whitespace andalso ?IS_WHITESPACE(C)));
_ ->
Len = O - Start,
<<_:Start/binary, Data:Len/binary, _/binary>> = B,
{{data, Data, Whitespace}, S}
end.
tokenize_attributes(B, S) ->
tokenize_attributes(B, S, []).
tokenize_attributes(B, S=#decoder{offset=O}, Acc) ->
case B of
<<_:O/binary>> ->
{lists:reverse(Acc), S};
<<_:O/binary, C, _/binary>> when (C =:= $> orelse C =:= $/) ->
{lists:reverse(Acc), S};
<<_:O/binary, "?>", _/binary>> ->
{lists:reverse(Acc), S};
<<_:O/binary, C, _/binary>> when ?IS_WHITESPACE(C) ->
tokenize_attributes(B, ?INC_CHAR(S, C), Acc);
_ ->
{Attr, S1} = tokenize_literal(B, S),
{Value, S2} = tokenize_attr_value(Attr, B, S1),
tokenize_attributes(B, S2, [{Attr, Value} | Acc])
end.
tokenize_attr_value(Attr, B, S) ->
S1 = skip_whitespace(B, S),
O = S1#decoder.offset,
case B of
<<_:O/binary, "=", _/binary>> ->
S2 = skip_whitespace(B, ?INC_COL(S1)),
tokenize_word_or_literal(B, S2);
_ ->
{Attr, S1}
end.
skip_whitespace(B, S=#decoder{offset=O}) ->
case B of
<<_:O/binary, C, _/binary>> when ?IS_WHITESPACE(C) ->
skip_whitespace(B, ?INC_CHAR(S, C));
_ ->
S
end.
tokenize_literal(Bin, S) ->
tokenize_literal(Bin, S, []).
tokenize_literal(Bin, S=#decoder{offset=O}, Acc) ->
case Bin of
<<_:O/binary, $&, _/binary>> ->
{{data, Data, false}, S1} = tokenize_charref(Bin, ?INC_COL(S)),
tokenize_literal(Bin, S1, [Data | Acc]);
<<_:O/binary, C, _/binary>> when not (?IS_WHITESPACE(C)
orelse C =:= $>
orelse C =:= $/
orelse C =:= $=) ->
tokenize_literal(Bin, ?INC_COL(S), [C | Acc]);
_ ->
{iolist_to_binary(lists:reverse(Acc)), S}
end.
find_qgt(Bin, S=#decoder{offset=O}) ->
case Bin of
<<_:O/binary, "?>", _/binary>> ->
?ADV_COL(S, 2);
<<_:O/binary, C, _/binary>> ->
find_qgt(Bin, ?INC_CHAR(S, C));
_ ->
S
end.
find_gt(Bin, S) ->
find_gt(Bin, S, false).
find_gt(Bin, S=#decoder{offset=O}, HasSlash) ->
case Bin of
<<_:O/binary, $/, _/binary>> ->
find_gt(Bin, ?INC_COL(S), true);
<<_:O/binary, $>, _/binary>> ->
{?INC_COL(S), HasSlash};
<<_:O/binary, C, _/binary>> ->
find_gt(Bin, ?INC_CHAR(S, C), HasSlash);
_ ->
{S, HasSlash}
end.
tokenize_charref(Bin, S=#decoder{offset=O}) ->
tokenize_charref(Bin, S, O).
tokenize_charref(Bin, S=#decoder{offset=O}, Start) ->
case Bin of
<<_:O/binary>> ->
<<_:Start/binary, Raw/binary>> = Bin,
{{data, Raw, false}, S};
<<_:O/binary, C, _/binary>> when ?IS_WHITESPACE(C)
orelse C =:= ?SQUOTE
orelse C =:= ?QUOTE
orelse C =:= $/
orelse C =:= $> ->
Len = O - Start,
<<_:Start/binary, Raw:Len/binary, _/binary>> = Bin,
{{data, Raw, false}, S};
<<_:O/binary, $;, _/binary>> ->
Len = O - Start,
<<_:Start/binary, Raw:Len/binary, _/binary>> = Bin,
Data = case mochiweb_charref:charref(Raw) of
undefined ->
Start1 = Start - 1,
Len1 = Len + 2,
<<_:Start1/binary, R:Len1/binary, _/binary>> = Bin,
R;
Unichar ->
list_to_binary(xmerl_ucs:to_utf8(Unichar))
end,
{{data, Data, false}, ?INC_COL(S)};
_ ->
tokenize_charref(Bin, ?INC_COL(S), Start)
end.
tokenize_doctype(Bin, S) ->
tokenize_doctype(Bin, S, []).
tokenize_doctype(Bin, S=#decoder{offset=O}, Acc) ->
case Bin of
<<_:O/binary>> ->
{{doctype, lists:reverse(Acc)}, S};
<<_:O/binary, $>, _/binary>> ->
{{doctype, lists:reverse(Acc)}, ?INC_COL(S)};
<<_:O/binary, C, _/binary>> when ?IS_WHITESPACE(C) ->
tokenize_doctype(Bin, ?INC_CHAR(S, C), Acc);
_ ->
{Word, S1} = tokenize_word_or_literal(Bin, S),
tokenize_doctype(Bin, S1, [Word | Acc])
end.
tokenize_word_or_literal(Bin, S=#decoder{offset=O}) ->
case Bin of
<<_:O/binary, C, _/binary>> when ?IS_WHITESPACE(C) ->
{error, {whitespace, [C], S}};
<<_:O/binary, C, _/binary>> when C =:= ?QUOTE orelse C =:= ?SQUOTE ->
tokenize_word(Bin, ?INC_COL(S), C);
_ ->
tokenize_literal(Bin, S, [])
end.
tokenize_word(Bin, S, Quote) ->
tokenize_word(Bin, S, Quote, []).
tokenize_word(Bin, S=#decoder{offset=O}, Quote, Acc) ->
case Bin of
<<_:O/binary>> ->
{iolist_to_binary(lists:reverse(Acc)), S};
<<_:O/binary, Quote, _/binary>> ->
{iolist_to_binary(lists:reverse(Acc)), ?INC_COL(S)};
<<_:O/binary, $&, _/binary>> ->
{{data, Data, false}, S1} = tokenize_charref(Bin, ?INC_COL(S)),
tokenize_word(Bin, S1, Quote, [Data | Acc]);
<<_:O/binary, C, _/binary>> ->
tokenize_word(Bin, ?INC_CHAR(S, C), Quote, [C | Acc])
end.
tokenize_cdata(Bin, S=#decoder{offset=O}) ->
tokenize_cdata(Bin, S, O).
tokenize_cdata(Bin, S=#decoder{offset=O}, Start) ->
case Bin of
<<_:O/binary, "]]>", _/binary>> ->
Len = O - Start,
<<_:Start/binary, Raw:Len/binary, _/binary>> = Bin,
{{data, Raw, false}, ?ADV_COL(S, 3)};
<<_:O/binary, C, _/binary>> ->
tokenize_cdata(Bin, ?INC_CHAR(S, C), Start);
_ ->
<<_:O/binary, Raw/binary>> = Bin,
{{data, Raw, false}, S}
end.
tokenize_comment(Bin, S=#decoder{offset=O}) ->
tokenize_comment(Bin, S, O).
tokenize_comment(Bin, S=#decoder{offset=O}, Start) ->
case Bin of
<<_:O/binary, "-->", _/binary>> ->
Len = O - Start,
<<_:Start/binary, Raw:Len/binary, _/binary>> = Bin,
{{comment, Raw}, ?ADV_COL(S, 3)};
<<_:O/binary, C, _/binary>> ->
tokenize_comment(Bin, ?INC_CHAR(S, C), Start);
<<_:Start/binary, Raw/binary>> ->
{{comment, Raw}, S}
end.
tokenize_script(Bin, S=#decoder{offset=O}) ->
tokenize_script(Bin, S, O).
tokenize_script(Bin, S=#decoder{offset=O}, Start) ->
case Bin of
%% Just a look-ahead, we want the end_tag separately
<<_:O/binary, $<, $/, SS, CC, RR, II, PP, TT, _/binary>>
when (SS =:= $s orelse SS =:= $S) andalso
(CC =:= $c orelse CC =:= $C) andalso
(RR =:= $r orelse RR =:= $R) andalso
(II =:= $i orelse II =:= $I) andalso
(PP =:= $p orelse PP =:= $P) andalso
(TT=:= $t orelse TT =:= $T) ->
Len = O - Start,
<<_:Start/binary, Raw:Len/binary, _/binary>> = Bin,
{{data, Raw, false}, S};
<<_:O/binary, C, _/binary>> ->
tokenize_script(Bin, ?INC_CHAR(S, C), Start);
<<_:Start/binary, Raw/binary>> ->
{{data, Raw, false}, S}
end.
tokenize_textarea(Bin, S=#decoder{offset=O}) ->
tokenize_textarea(Bin, S, O).
tokenize_textarea(Bin, S=#decoder{offset=O}, Start) ->
case Bin of
%% Just a look-ahead, we want the end_tag separately
<<_:O/binary, $<, $/, TT, EE, XX, TT2, AA, RR, EE2, AA2, _/binary>>
when (TT =:= $t orelse TT =:= $T) andalso
(EE =:= $e orelse EE =:= $E) andalso
(XX =:= $x orelse XX =:= $X) andalso
(TT2 =:= $t orelse TT2 =:= $T) andalso
(AA =:= $a orelse AA =:= $A) andalso
(RR =:= $r orelse RR =:= $R) andalso
(EE2 =:= $e orelse EE2 =:= $E) andalso
(AA2 =:= $a orelse AA2 =:= $A) ->
Len = O - Start,
<<_:Start/binary, Raw:Len/binary, _/binary>> = Bin,
{{data, Raw, false}, S};
<<_:O/binary, C, _/binary>> ->
tokenize_textarea(Bin, ?INC_CHAR(S, C), Start);
<<_:Start/binary, Raw/binary>> ->
{{data, Raw, false}, S}
end.