sailfish/runtime/escape/
mod.rs

1//! HTML escaping utilities
2//!
3//! By default sailfish replaces the characters `&"'<>` with the equivalent html.
4
5#![cfg_attr(
6    all(
7        any(target_arch = "x86", target_arch = "x86_64"),
8        not(miri),
9        target_feature = "avx2"
10    ),
11    allow(dead_code)
12)]
13
14#[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), not(miri)))]
15mod avx2;
16mod fallback;
17mod naive;
18#[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), not(miri)))]
19mod sse2;
20
21static ESCAPE_LUT: [u8; 256] = [
22    9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
23    9, 9, 9, 9, 9, 9, 0, 9, 9, 9, 1, 2, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
24    9, 9, 9, 9, 3, 9, 4, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
25    9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
26    9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
27    9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
28    9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
29    9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
30    9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
31    9, 9, 9, 9,
32];
33
34const ESCAPED: [&str; 5] = ["&quot;", "&amp;", "&#039;", "&lt;", "&gt;"];
35const ESCAPED_LEN: usize = 5;
36
37use super::buffer::Buffer;
38
39/// write the escaped contents into `Buffer`
40#[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), not(miri)))]
41#[cfg_attr(feature = "perf-inline", inline)]
42pub fn escape_to_buf(feed: &str, buf: &mut Buffer) {
43    #[cfg(not(target_feature = "avx2"))]
44    {
45        use std::sync::atomic::{AtomicPtr, Ordering};
46
47        type FnRaw = *mut ();
48        static FN: AtomicPtr<()> = AtomicPtr::new(detect as FnRaw);
49
50        fn detect(feed: &str, buf: &mut Buffer) {
51            debug_assert!(feed.len() >= 16);
52            let fun = if is_x86_feature_detected!("avx2") {
53                avx2::escape
54            } else if is_x86_feature_detected!("sse2") {
55                sse2::escape
56            } else {
57                fallback::escape
58            };
59
60            FN.store(fun as FnRaw, Ordering::Relaxed);
61            unsafe { fun(feed, buf) };
62        }
63
64        unsafe {
65            if feed.len() < 16 {
66                buf.reserve_small(feed.len() * 6);
67                let l = naive::escape_small(feed, buf.as_mut_ptr().add(buf.len()));
68                buf.advance(l);
69            } else {
70                let fun = FN.load(Ordering::Relaxed);
71                std::mem::transmute::<FnRaw, fn(&str, &mut Buffer)>(fun)(feed, buf);
72            }
73        }
74    }
75
76    #[cfg(target_feature = "avx2")]
77    unsafe {
78        if feed.len() < 16 {
79            buf.reserve_small(feed.len() * 6);
80            let l = naive::escape_small(feed, buf.as_mut_ptr().add(buf.len()));
81            buf.advance(l);
82        } else if cfg!(target_feature = "avx2") {
83            avx2::escape(feed, buf);
84        }
85    }
86}
87
88/// write the escaped contents into `Buffer`
89#[cfg(not(all(any(target_arch = "x86", target_arch = "x86_64"), not(miri))))]
90#[cfg_attr(feature = "perf-inline", inline)]
91pub fn escape_to_buf(feed: &str, buf: &mut Buffer) {
92    unsafe {
93        if cfg!(miri) {
94            let bp = feed.as_ptr();
95            naive::escape(buf, bp, bp, bp.add(feed.len()))
96        } else if feed.len() < 16 {
97            buf.reserve_small(feed.len() * 6);
98            let l = naive::escape_small(feed, buf.as_mut_ptr().add(buf.len()));
99            buf.advance(l);
100        } else {
101            fallback::escape(feed, buf)
102        }
103    }
104}
105
106/// write the escaped contents into `String`
107///
108/// # Examples
109///
110/// ```
111/// use sailfish::runtime::escape::escape_to_string;
112///
113/// let mut buf = String::new();
114/// escape_to_string("<h1>Hello, world!</h1>", &mut buf);
115/// assert_eq!(buf, "&lt;h1&gt;Hello, world!&lt;/h1&gt;");
116/// ```
117#[inline]
118pub fn escape_to_string(feed: &str, s: &mut String) {
119    let mut s2 = String::new();
120    std::mem::swap(s, &mut s2);
121    let mut buf = Buffer::from(s2);
122    escape_to_buf(feed, &mut buf);
123    let mut s2 = buf.into_string();
124    std::mem::swap(s, &mut s2);
125}
126
127#[cfg(test)]
128mod tests {
129    use super::*;
130
131    fn escape(feed: &str) -> String {
132        let mut s = String::new();
133        escape_to_string(feed, &mut s);
134        s
135    }
136
137    #[test]
138    fn noescape() {
139        assert_eq!(escape(""), "");
140        assert_eq!(escape("1234567890"), "1234567890");
141        assert_eq!(
142            escape("abcdefghijklmnopqrstrvwxyz"),
143            "abcdefghijklmnopqrstrvwxyz"
144        );
145        assert_eq!(escape("!#$%()*+,-.:;=?_^"), "!#$%()*+,-.:;=?_^");
146        assert_eq!(
147            escape("漢字はエスケープしないはずだよ"),
148            "漢字はエスケープしないはずだよ"
149        );
150    }
151
152    #[test]
153    fn escape_short() {
154        assert_eq!(escape("<"), "&lt;");
155        assert_eq!(escape("\"&<>'"), "&quot;&amp;&lt;&gt;&#039;");
156        assert_eq!(
157            escape("{\"title\": \"This is a JSON!\"}"),
158            "{&quot;title&quot;: &quot;This is a JSON!&quot;}"
159        );
160        assert_eq!(
161            escape("<html><body><h1>Hello, world</h1></body></html>"),
162            "&lt;html&gt;&lt;body&gt;&lt;h1&gt;Hello, world&lt;/h1&gt;\
163            &lt;/body&gt;&lt;/html&gt;"
164        );
165    }
166
167    #[test]
168    #[rustfmt::skip]
169    fn escape_long() {
170        assert_eq!(
171            escape(r###"m{jml&,?6>\2~08g)\=3`,_`$1@0{i5j}.}2ki\^t}k"'@p4$~?;!;pn_l8v."ki`%/&^=\[y+qcerr`@3*|?du.\0vd#40'.>bcpf\u@m|c<2t7`hk)^?"0u{v%9}4y2hhv?%-f`<;rzwx`7}l(j2b:c\<|z&$x{+k;f`0+w3e0\m.wmdli>94e2hp\$}j0&m(*h$/lwlj#}99r';o.kj@1#}~v+;y~b[~m.eci}&l7fxt`\\{~#k*9z/d{}(.^j}[(,]:<\h]9k2+0*w60/|23~5;/!-h&ci*~e1h~+:1lhh\>y_*>:-\zzv+8uo],,a^k3_,uip]-/.-~\t51a*<{6!<(_|<#o6=\h1*`[2x_?#-/])x};};r@wqx|;/w&jrv~?\`t:^/dug3(g(ener?!t$}h4:57ptnm@71e=t>@o*"$]799r=+)t>co?rvgk%u0c@.9os;#t_*/gqv<za&~r^]"{t4by2t`<q4bfo^&!so5/~(nxk:7l\;#0w41u~w3i$g|>e/t;o<*`~?3.jyx+h)+^cn^j4td|>)~rs)vm#]:"&\fi;54%+z~fhe|w~\q|ui={54[b9tg*?@]g+q!mq]3jg2?eoo"chyat3k#7pq1u=.l]c14twa4tg#5k_""###),
172            r###"m{jml&amp;,?6&gt;\2~08g)\=3`,_`$1@0{i5j}.}2ki\^t}k&quot;&#039;@p4$~?;!;pn_l8v.&quot;ki`%/&amp;^=\[y+qcerr`@3*|?du.\0vd#40&#039;.&gt;bcpf\u@m|c&lt;2t7`hk)^?&quot;0u{v%9}4y2hhv?%-f`&lt;;rzwx`7}l(j2b:c\&lt;|z&amp;$x{+k;f`0+w3e0\m.wmdli&gt;94e2hp\$}j0&amp;m(*h$/lwlj#}99r&#039;;o.kj@1#}~v+;y~b[~m.eci}&amp;l7fxt`\\{~#k*9z/d{}(.^j}[(,]:&lt;\h]9k2+0*w60/|23~5;/!-h&amp;ci*~e1h~+:1lhh\&gt;y_*&gt;:-\zzv+8uo],,a^k3_,uip]-/.-~\t51a*&lt;{6!&lt;(_|&lt;#o6=\h1*`[2x_?#-/])x};};r@wqx|;/w&amp;jrv~?\`t:^/dug3(g(ener?!t$}h4:57ptnm@71e=t&gt;@o*&quot;$]799r=+)t&gt;co?rvgk%u0c@.9os;#t_*/gqv&lt;za&amp;~r^]&quot;{t4by2t`&lt;q4bfo^&amp;!so5/~(nxk:7l\;#0w41u~w3i$g|&gt;e/t;o&lt;*`~?3.jyx+h)+^cn^j4td|&gt;)~rs)vm#]:&quot;&amp;\fi;54%+z~fhe|w~\q|ui={54[b9tg*?@]g+q!mq]3jg2?eoo&quot;chyat3k#7pq1u=.l]c14twa4tg#5k_&quot;"###
173        );
174    }
175
176    #[test]
177    #[cfg(not(miri))]
178    fn random() {
179        const ASCII_CHARS: &'static [u8] = br##"abcdefghijklmnopqrstuvwxyz0123456789-^\@[;:],./\!"#$%&'()~=~|`{+*}<>?_"##;
180        let mut state = 88172645463325252u64;
181        let mut data = Vec::with_capacity(100);
182
183        let mut buf_naive = Buffer::new();
184        let mut buf = Buffer::new();
185
186        for len in 16..100 {
187            for _ in 0..5 {
188                data.clear();
189                for _ in 0..len {
190                    // xorshift
191                    state ^= state << 13;
192                    state ^= state >> 7;
193                    state ^= state << 17;
194
195                    let idx = state as usize % ASCII_CHARS.len();
196                    data.push(ASCII_CHARS[idx]);
197                }
198
199                let s = unsafe { std::str::from_utf8_unchecked(&*data) };
200
201                unsafe {
202                    naive::escape(
203                        &mut buf_naive,
204                        s.as_ptr(),
205                        s.as_ptr(),
206                        s.as_ptr().add(s.len()),
207                    );
208
209                    fallback::escape(s, &mut buf);
210                    assert_eq!(buf.as_str(), buf_naive.as_str());
211                    buf.clear();
212
213                    #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
214                    {
215                        if is_x86_feature_detected!("sse2") {
216                            sse2::escape(s, &mut buf);
217                            assert_eq!(buf.as_str(), buf_naive.as_str());
218                            buf.clear();
219                        }
220
221                        if is_x86_feature_detected!("avx2") {
222                            avx2::escape(s, &mut buf);
223                            assert_eq!(buf.as_str(), buf_naive.as_str());
224                            buf.clear();
225                        }
226                    }
227                }
228
229                buf_naive.clear();
230            }
231        }
232    }
233}
sailfish/runtime/escape/mod.rs

sailfish/runtime/escape/
mod.rs
