hyper/
headers.rs

1#[cfg(all(feature = "client", feature = "http1"))]
2use bytes::BytesMut;
3use http::header::HeaderValue;
4#[cfg(all(feature = "http2", feature = "client"))]
5use http::Method;
6#[cfg(any(feature = "client", all(feature = "server", feature = "http2")))]
7use http::{
8    header::{ValueIter, CONTENT_LENGTH},
9    HeaderMap,
10};
11
12#[cfg(feature = "http1")]
13pub(super) fn connection_keep_alive(value: &HeaderValue) -> bool {
14    connection_has(value, "keep-alive")
15}
16
17#[cfg(feature = "http1")]
18pub(super) fn connection_close(value: &HeaderValue) -> bool {
19    connection_has(value, "close")
20}
21
22#[cfg(feature = "http1")]
23fn connection_has(value: &HeaderValue, needle: &str) -> bool {
24    if let Ok(s) = value.to_str() {
25        for val in s.split(',') {
26            if val.trim().eq_ignore_ascii_case(needle) {
27                return true;
28            }
29        }
30    }
31    false
32}
33
34#[cfg(all(feature = "http1", feature = "server"))]
35pub(super) fn content_length_parse(value: &HeaderValue) -> Option<u64> {
36    from_digits(value.as_bytes())
37}
38
39#[cfg(any(feature = "client", all(feature = "server", feature = "http2")))]
40pub(super) fn content_length_parse_all(headers: &HeaderMap) -> Option<u64> {
41    content_length_parse_all_values(headers.get_all(CONTENT_LENGTH).into_iter())
42}
43
44#[cfg(any(feature = "client", all(feature = "server", feature = "http2")))]
45pub(super) fn content_length_parse_all_values(values: ValueIter<'_, HeaderValue>) -> Option<u64> {
46    // If multiple Content-Length headers were sent, everything can still
47    // be alright if they all contain the same value, and all parse
48    // correctly. If not, then it's an error.
49
50    let mut content_length: Option<u64> = None;
51    for h in values {
52        if let Ok(line) = h.to_str() {
53            for v in line.split(',') {
54                if let Some(n) = from_digits(v.trim().as_bytes()) {
55                    if content_length.is_none() {
56                        content_length = Some(n)
57                    } else if content_length != Some(n) {
58                        return None;
59                    }
60                } else {
61                    return None;
62                }
63            }
64        } else {
65            return None;
66        }
67    }
68
69    content_length
70}
71
72fn from_digits(bytes: &[u8]) -> Option<u64> {
73    // cannot use FromStr for u64, since it allows a signed prefix
74    let mut result = 0u64;
75    const RADIX: u64 = 10;
76
77    if bytes.is_empty() {
78        return None;
79    }
80
81    for &b in bytes {
82        // can't use char::to_digit, since we haven't verified these bytes
83        // are utf-8.
84        match b {
85            b'0'..=b'9' => {
86                result = result.checked_mul(RADIX)?;
87                result = result.checked_add((b - b'0') as u64)?;
88            }
89            _ => {
90                // not a DIGIT, get outta here!
91                return None;
92            }
93        }
94    }
95
96    Some(result)
97}
98
99#[cfg(all(feature = "http2", feature = "client"))]
100pub(super) fn method_has_defined_payload_semantics(method: &Method) -> bool {
101    !matches!(
102        *method,
103        Method::GET | Method::HEAD | Method::DELETE | Method::CONNECT
104    )
105}
106
107#[cfg(feature = "http2")]
108pub(super) fn set_content_length_if_missing(headers: &mut HeaderMap, len: u64) {
109    headers
110        .entry(CONTENT_LENGTH)
111        .or_insert_with(|| HeaderValue::from(len));
112}
113
114#[cfg(all(feature = "client", feature = "http1"))]
115pub(super) fn transfer_encoding_is_chunked(headers: &HeaderMap) -> bool {
116    is_chunked(headers.get_all(http::header::TRANSFER_ENCODING).into_iter())
117}
118
119#[cfg(all(feature = "client", feature = "http1"))]
120pub(super) fn is_chunked(mut encodings: ValueIter<'_, HeaderValue>) -> bool {
121    // chunked must always be the last encoding, according to spec
122    if let Some(line) = encodings.next_back() {
123        return is_chunked_(line);
124    }
125
126    false
127}
128
129#[cfg(feature = "http1")]
130pub(super) fn is_chunked_(value: &HeaderValue) -> bool {
131    // chunked must always be the last encoding, according to spec
132    if let Ok(s) = value.to_str() {
133        if let Some(encoding) = s.rsplit(',').next() {
134            return encoding.trim().eq_ignore_ascii_case("chunked");
135        }
136    }
137
138    false
139}
140
141#[cfg(all(feature = "client", feature = "http1"))]
142pub(super) fn add_chunked(mut entry: http::header::OccupiedEntry<'_, HeaderValue>) {
143    const CHUNKED: &str = "chunked";
144
145    if let Some(line) = entry.iter_mut().next_back() {
146        // + 2 for ", "
147        let new_cap = line.as_bytes().len() + CHUNKED.len() + 2;
148        let mut buf = BytesMut::with_capacity(new_cap);
149        buf.extend_from_slice(line.as_bytes());
150        buf.extend_from_slice(b", ");
151        buf.extend_from_slice(CHUNKED.as_bytes());
152
153        *line = HeaderValue::from_maybe_shared(buf.freeze())
154            .expect("original header value plus ascii is valid");
155        return;
156    }
157
158    entry.insert(HeaderValue::from_static(CHUNKED));
159}
hyper/headers.rs

hyper/
headers.rs
