//! HTML escaping utilities
//!
//! By default sailfish replaces the characters `&"'<>` with the equivalent html.
#![cfg_attr(
all(
any(target_arch = "x86", target_arch = "x86_64"),
not(miri),
target_feature = "avx2"
),
allow(dead_code)
)]
#[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), not(miri)))]
mod avx2;
mod fallback;
mod naive;
#[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), not(miri)))]
mod sse2;
static ESCAPE_LUT: [u8; 256] = [
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,
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,
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,
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,
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,
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,
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,
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,
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,
9, 9, 9, 9,
];
const ESCAPED: [&str; 5] = [""", "&", "'", "<", ">"];
const ESCAPED_LEN: usize = 5;
use super::buffer::Buffer;
/// write the escaped contents into `Buffer`
#[cfg(all(any(target_arch = "x86", target_arch = "x86_64"), not(miri)))]
#[cfg_attr(feature = "perf-inline", inline)]
pub fn escape_to_buf(feed: &str, buf: &mut Buffer) {
#[cfg(not(target_feature = "avx2"))]
{
use std::sync::atomic::{AtomicPtr, Ordering};
type FnRaw = *mut ();
static FN: AtomicPtr<()> = AtomicPtr::new(detect as FnRaw);
fn detect(feed: &str, buf: &mut Buffer) {
debug_assert!(feed.len() >= 16);
let fun = if is_x86_feature_detected!("avx2") {
avx2::escape
} else if is_x86_feature_detected!("sse2") {
sse2::escape
} else {
fallback::escape
};
FN.store(fun as FnRaw, Ordering::Relaxed);
unsafe { fun(feed, buf) };
}
unsafe {
if feed.len() < 16 {
buf.reserve_small(feed.len() * 6);
let l = naive::escape_small(feed, buf.as_mut_ptr().add(buf.len()));
buf.advance(l);
} else {
let fun = FN.load(Ordering::Relaxed);
std::mem::transmute::<FnRaw, fn(&str, &mut Buffer)>(fun)(feed, buf);
}
}
}
#[cfg(target_feature = "avx2")]
unsafe {
if feed.len() < 16 {
buf.reserve_small(feed.len() * 6);
let l = naive::escape_small(feed, buf.as_mut_ptr().add(buf.len()));
buf.advance(l);
} else if cfg!(target_feature = "avx2") {
avx2::escape(feed, buf);
}
}
}
/// write the escaped contents into `Buffer`
#[cfg(not(all(any(target_arch = "x86", target_arch = "x86_64"), not(miri))))]
#[cfg_attr(feature = "perf-inline", inline)]
pub fn escape_to_buf(feed: &str, buf: &mut Buffer) {
unsafe {
if cfg!(miri) {
let bp = feed.as_ptr();
naive::escape(buf, bp, bp, bp.add(feed.len()))
} else if feed.len() < 16 {
buf.reserve_small(feed.len() * 6);
let l = naive::escape_small(feed, buf.as_mut_ptr().add(buf.len()));
buf.advance(l);
} else {
fallback::escape(feed, buf)
}
}
}
/// write the escaped contents into `String`
///
/// # Examples
///
/// ```
/// use sailfish::runtime::escape::escape_to_string;
///
/// let mut buf = String::new();
/// escape_to_string("<h1>Hello, world!</h1>", &mut buf);
/// assert_eq!(buf, "<h1>Hello, world!</h1>");
/// ```
#[inline]
pub fn escape_to_string(feed: &str, s: &mut String) {
let mut s2 = String::new();
std::mem::swap(s, &mut s2);
let mut buf = Buffer::from(s2);
escape_to_buf(feed, &mut buf);
let mut s2 = buf.into_string();
std::mem::swap(s, &mut s2);
}
#[cfg(test)]
mod tests {
use super::*;
fn escape(feed: &str) -> String {
let mut s = String::new();
escape_to_string(feed, &mut s);
s
}
#[test]
fn noescape() {
assert_eq!(escape(""), "");
assert_eq!(escape("1234567890"), "1234567890");
assert_eq!(
escape("abcdefghijklmnopqrstrvwxyz"),
"abcdefghijklmnopqrstrvwxyz"
);
assert_eq!(escape("!#$%()*+,-.:;=?_^"), "!#$%()*+,-.:;=?_^");
assert_eq!(
escape("漢字はエスケープしないはずだよ"),
"漢字はエスケープしないはずだよ"
);
}
#[test]
fn escape_short() {
assert_eq!(escape("<"), "<");
assert_eq!(escape("\"&<>'"), ""&<>'");
assert_eq!(
escape("{\"title\": \"This is a JSON!\"}"),
"{"title": "This is a JSON!"}"
);
assert_eq!(
escape("<html><body><h1>Hello, world</h1></body></html>"),
"<html><body><h1>Hello, world</h1>\
</body></html>"
);
}
#[test]
#[rustfmt::skip]
fn escape_long() {
assert_eq!(
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_""###),
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$g|>e/t;o<*`~?3.jyx+h)+^cn^j4td|>)~rs)vm#]:"&\fi;54%+z~fhe|w~\q|ui={54[b9tg*?@]g+q!mq]3jg2?eoo"chyat3k#7pq1u=.l]c14twa4tg#5k_""###
);
}
#[test]
#[cfg(not(miri))]
fn random() {
const ASCII_CHARS: &'static [u8] = br##"abcdefghijklmnopqrstuvwxyz0123456789-^\@[;:],./\!"#$%&'()~=~|`{+*}<>?_"##;
let mut state = 88172645463325252u64;
let mut data = Vec::with_capacity(100);
let mut buf_naive = Buffer::new();
let mut buf = Buffer::new();
for len in 16..100 {
for _ in 0..5 {
data.clear();
for _ in 0..len {
// xorshift
state ^= state << 13;
state ^= state >> 7;
state ^= state << 17;
let idx = state as usize % ASCII_CHARS.len();
data.push(ASCII_CHARS[idx]);
}
let s = unsafe { std::str::from_utf8_unchecked(&*data) };
unsafe {
naive::escape(
&mut buf_naive,
s.as_ptr(),
s.as_ptr(),
s.as_ptr().add(s.len()),
);
fallback::escape(s, &mut buf);
assert_eq!(buf.as_str(), buf_naive.as_str());
buf.clear();
#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
{
if is_x86_feature_detected!("sse2") {
sse2::escape(s, &mut buf);
assert_eq!(buf.as_str(), buf_naive.as_str());
buf.clear();
}
if is_x86_feature_detected!("avx2") {
avx2::escape(s, &mut buf);
assert_eq!(buf.as_str(), buf_naive.as_str());
buf.clear();
}
}
}
buf_naive.clear();
}
}
}
}