1 files changed, 154 insertions, 0 deletions
diff --git a/third_party/rust/hyper/src/headers.rs b/third_party/rust/hyper/src/headers.rs
new file mode 100644
index 0000000000..8407be185f
--- /dev/null
+++ b/third_party/rust/hyper/src/headers.rs
@@ -0,0 +1,154 @@
+#[cfg(feature = "http1")]
+use bytes::BytesMut;
+use http::header::CONTENT_LENGTH;
+use http::header::{HeaderValue, ValueIter};
+use http::HeaderMap;
+#[cfg(all(feature = "http2", feature = "client"))]
+use http::Method;
+
+#[cfg(feature = "http1")]
+pub(super) fn connection_keep_alive(value: &HeaderValue) -> bool {
+    connection_has(value, "keep-alive")
+}
+
+#[cfg(feature = "http1")]
+pub(super) fn connection_close(value: &HeaderValue) -> bool {
+    connection_has(value, "close")
+}
+
+#[cfg(feature = "http1")]
+fn connection_has(value: &HeaderValue, needle: &str) -> bool {
+    if let Ok(s) = value.to_str() {
+        for val in s.split(',') {
+            if val.trim().eq_ignore_ascii_case(needle) {
+                return true;
+            }
+        }
+    }
+    false
+}
+
+#[cfg(all(feature = "http1", feature = "server"))]
+pub(super) fn content_length_parse(value: &HeaderValue) -> Option<u64> {
+    from_digits(value.as_bytes())
+}
+
+pub(super) fn content_length_parse_all(headers: &HeaderMap) -> Option<u64> {
+    content_length_parse_all_values(headers.get_all(CONTENT_LENGTH).into_iter())
+}
+
+pub(super) fn content_length_parse_all_values(values: ValueIter<'_, HeaderValue>) -> Option<u64> {
+    // If multiple Content-Length headers were sent, everything can still
+    // be alright if they all contain the same value, and all parse
+    // correctly. If not, then it's an error.
+
+    let mut content_length: Option<u64> = None;
+    for h in values {
+        if let Ok(line) = h.to_str() {
+            for v in line.split(',') {
+                if let Some(n) = from_digits(v.trim().as_bytes()) {
+                    if content_length.is_none() {
+                        content_length = Some(n)
+                    } else if content_length != Some(n) {
+                        return None;
+                    }
+                } else {
+                    return None
+                }
+            }
+        } else {
+            return None
+        }
+    }
+
+    return content_length
+}
+
+fn from_digits(bytes: &[u8]) -> Option<u64> {
+    // cannot use FromStr for u64, since it allows a signed prefix
+    let mut result = 0u64;
+    const RADIX: u64 = 10;
+
+    if bytes.is_empty() {
+        return None;
+    }
+
+    for &b in bytes {
+        // can't use char::to_digit, since we haven't verified these bytes
+        // are utf-8.
+        match b {
+            b'0'..=b'9' => {
+                result = result.checked_mul(RADIX)?;
+                result = result.checked_add((b - b'0') as u64)?;
+            },
+            _ => {
+                // not a DIGIT, get outta here!
+                return None;
+            }
+        }
+    }
+
+    Some(result)
+}
+
+#[cfg(all(feature = "http2", feature = "client"))]
+pub(super) fn method_has_defined_payload_semantics(method: &Method) -> bool {
+    match *method {
+        Method::GET | Method::HEAD | Method::DELETE | Method::CONNECT => false,
+        _ => true,
+    }
+}
+
+#[cfg(feature = "http2")]
+pub(super) fn set_content_length_if_missing(headers: &mut HeaderMap, len: u64) {
+    headers
+        .entry(CONTENT_LENGTH)
+        .or_insert_with(|| HeaderValue::from(len));
+}
+
+#[cfg(feature = "http1")]
+pub(super) fn transfer_encoding_is_chunked(headers: &HeaderMap) -> bool {
+    is_chunked(headers.get_all(http::header::TRANSFER_ENCODING).into_iter())
+}
+
+#[cfg(feature = "http1")]
+pub(super) fn is_chunked(mut encodings: ValueIter<'_, HeaderValue>) -> bool {
+    // chunked must always be the last encoding, according to spec
+    if let Some(line) = encodings.next_back() {
+        return is_chunked_(line);
+    }
+
+    false
+}
+
+#[cfg(feature = "http1")]
+pub(super) fn is_chunked_(value: &HeaderValue) -> bool {
+    // chunked must always be the last encoding, according to spec
+    if let Ok(s) = value.to_str() {
+        if let Some(encoding) = s.rsplit(',').next() {
+            return encoding.trim().eq_ignore_ascii_case("chunked");
+        }
+    }
+
+    false
+}
+
+#[cfg(feature = "http1")]
+pub(super) fn add_chunked(mut entry: http::header::OccupiedEntry<'_, HeaderValue>) {
+    const CHUNKED: &str = "chunked";
+
+    if let Some(line) = entry.iter_mut().next_back() {
+        // + 2 for ", "
+        let new_cap = line.as_bytes().len() + CHUNKED.len() + 2;
+        let mut buf = BytesMut::with_capacity(new_cap);
+        buf.extend_from_slice(line.as_bytes());
+        buf.extend_from_slice(b", ");
+        buf.extend_from_slice(CHUNKED.as_bytes());
+
+        *line = HeaderValue::from_maybe_shared(buf.freeze())
+            .expect("original header value plus ascii is valid");
+        return;
+    }
+
+    entry.insert(HeaderValue::from_static(CHUNKED));
+}