use std::mem;
use bytes::BytesMut;
use http::HeaderMap;
use http::header::{CONTENT_LENGTH, TRANSFER_ENCODING};
use http::header::{HeaderValue, OccupiedEntry, ValueIter};
const MAX_DECIMAL_U64_BYTES: usize = 20;
pub fn connection_keep_alive(value: &HeaderValue) -> bool {
connection_has(value, "keep-alive")
}
pub fn connection_close(value: &HeaderValue) -> bool {
connection_has(value, "close")
}
fn connection_has(value: &HeaderValue, needle: &str) -> bool {
if let Ok(s) = value.to_str() {
for val in s.split(',') {
if eq_ascii(val.trim(), needle) {
return true;
}
}
}
false
}
pub fn content_length_parse(value: &HeaderValue) -> Option<u64> {
value
.to_str()
.ok()
.and_then(|s| s.parse().ok())
}
pub fn content_length_parse_all(headers: &HeaderMap) -> Option<u64> {
content_length_parse_all_values(headers.get_all(CONTENT_LENGTH).into_iter())
}
pub fn content_length_parse_all_values(values: ValueIter<HeaderValue>) -> Option<u64> {
let folded = values
.fold(None, |prev, line| match prev {
Some(Ok(prev)) => {
Some(line
.to_str()
.map_err(|_| ())
.and_then(|s| s.parse().map_err(|_| ()))
.and_then(|n| if prev == n { Ok(n) } else { Err(()) }))
},
None => {
Some(line
.to_str()
.map_err(|_| ())
.and_then(|s| s.parse().map_err(|_| ())))
},
Some(Err(())) => Some(Err(())),
});
if let Some(Ok(n)) = folded {
Some(n)
} else {
None
}
}
pub fn content_length_value(len: u64) -> HeaderValue {
let mut len_buf = if mem::size_of::<BytesMut>() - 1 < MAX_DECIMAL_U64_BYTES {
const MAX_DECIMAL_INLINE: u64 = 999_999_999_999_999;
if len <= MAX_DECIMAL_INLINE {
BytesMut::new()
} else {
BytesMut::with_capacity(MAX_DECIMAL_U64_BYTES)
}
} else {
BytesMut::with_capacity(MAX_DECIMAL_U64_BYTES)
};
::itoa::fmt(&mut len_buf, len)
.expect("BytesMut can hold a decimal u64");
unsafe {
HeaderValue::from_shared_unchecked(len_buf.freeze())
}
}
pub fn set_content_length_if_missing(headers: &mut HeaderMap, len: u64) {
headers
.entry(CONTENT_LENGTH)
.unwrap()
.or_insert(content_length_value(len));
}
pub fn transfer_encoding_is_chunked(headers: &HeaderMap) -> bool {
is_chunked(headers.get_all(TRANSFER_ENCODING).into_iter())
}
pub fn is_chunked(mut encodings: ValueIter<HeaderValue>) -> bool {
if let Some(line) = encodings.next_back() {
return is_chunked_(line);
}
false
}
pub fn is_chunked_(value: &HeaderValue) -> bool {
if let Ok(s) = value.to_str() {
if let Some(encoding) = s.rsplit(',').next() {
return eq_ascii(encoding.trim(), "chunked");
}
}
false
}
pub fn add_chunked(mut entry: OccupiedEntry<HeaderValue>) {
const CHUNKED: &'static str = "chunked";
if let Some(line) = entry.iter_mut().next_back() {
let new_cap = line.as_bytes().len() + CHUNKED.len() + 2;
let mut buf = BytesMut::with_capacity(new_cap);
buf.copy_from_slice(line.as_bytes());
buf.copy_from_slice(b", ");
buf.copy_from_slice(CHUNKED.as_bytes());
*line = HeaderValue::from_shared(buf.freeze())
.expect("original header value plus ascii is valid");
return;
}
entry.insert(HeaderValue::from_static(CHUNKED));
}
fn eq_ascii(left: &str, right: &str) -> bool {
#[allow(unused, deprecated)]
use std::ascii::AsciiExt;
left.eq_ignore_ascii_case(right)
}
#[cfg(test)]
mod tests {
#[cfg(feature = "nightly")]
use test::Bencher;
#[test]
fn assert_max_decimal_u64_bytes() {
assert_eq!(
super::MAX_DECIMAL_U64_BYTES,
::std::u64::MAX.to_string().len()
);
}
#[cfg(feature = "nightly")]
#[bench]
fn bench_content_length_fmt_small(b: &mut Bencher) {
let n = 13;
let s = n.to_string();
b.bytes = s.len() as u64;
b.iter(|| {
let val = super::content_length_value(n);
debug_assert_eq!(val, s);
::test::black_box(&val);
})
}
#[cfg(feature = "nightly")]
#[bench]
fn bench_content_length_fmt_big(b: &mut Bencher) {
let n = 326_893_010;
let s = n.to_string();
b.bytes = s.len() as u64;
b.iter(|| {
let val = super::content_length_value(n);
debug_assert_eq!(val, s);
::test::black_box(&val);
})
}
}