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use super::{util, StreamDependency, StreamId};
use crate::ext::Protocol;
use crate::frame::{Error, Frame, Head, Kind};
use crate::hpack::{self, BytesStr};
use http::header::{self, HeaderName, HeaderValue};
use http::{uri, HeaderMap, Method, Request, StatusCode, Uri};
use bytes::{BufMut, Bytes, BytesMut};
use std::fmt;
use std::io::Cursor;
type EncodeBuf<'a> = bytes::buf::Limit<&'a mut BytesMut>;
/// Header frame
///
/// This could be either a request or a response.
#[derive(Eq, PartialEq)]
pub struct Headers {
/// The ID of the stream with which this frame is associated.
stream_id: StreamId,
/// The stream dependency information, if any.
stream_dep: Option<StreamDependency>,
/// The header block fragment
header_block: HeaderBlock,
/// The associated flags
flags: HeadersFlag,
}
#[derive(Copy, Clone, Eq, PartialEq)]
pub struct HeadersFlag(u8);
#[derive(Eq, PartialEq)]
pub struct PushPromise {
/// The ID of the stream with which this frame is associated.
stream_id: StreamId,
/// The ID of the stream being reserved by this PushPromise.
promised_id: StreamId,
/// The header block fragment
header_block: HeaderBlock,
/// The associated flags
flags: PushPromiseFlag,
}
#[derive(Copy, Clone, Eq, PartialEq)]
pub struct PushPromiseFlag(u8);
#[derive(Debug)]
pub struct Continuation {
/// Stream ID of continuation frame
stream_id: StreamId,
header_block: EncodingHeaderBlock,
}
// TODO: These fields shouldn't be `pub`
#[derive(Debug, Default, Eq, PartialEq)]
pub struct Pseudo {
// Request
pub method: Option<Method>,
pub scheme: Option<BytesStr>,
pub authority: Option<BytesStr>,
pub path: Option<BytesStr>,
pub protocol: Option<Protocol>,
// Response
pub status: Option<StatusCode>,
}
#[derive(Debug)]
pub struct Iter {
/// Pseudo headers
pseudo: Option<Pseudo>,
/// Header fields
fields: header::IntoIter<HeaderValue>,
}
#[derive(Debug, PartialEq, Eq)]
struct HeaderBlock {
/// The decoded header fields
fields: HeaderMap,
/// Set to true if decoding went over the max header list size.
is_over_size: bool,
/// Pseudo headers, these are broken out as they must be sent as part of the
/// headers frame.
pseudo: Pseudo,
}
#[derive(Debug)]
struct EncodingHeaderBlock {
hpack: Bytes,
}
const END_STREAM: u8 = 0x1;
const END_HEADERS: u8 = 0x4;
const PADDED: u8 = 0x8;
const PRIORITY: u8 = 0x20;
const ALL: u8 = END_STREAM | END_HEADERS | PADDED | PRIORITY;
// ===== impl Headers =====
impl Headers {
/// Create a new HEADERS frame
pub fn new(stream_id: StreamId, pseudo: Pseudo, fields: HeaderMap) -> Self {
Headers {
stream_id,
stream_dep: None,
header_block: HeaderBlock {
fields,
is_over_size: false,
pseudo,
},
flags: HeadersFlag::default(),
}
}
pub fn trailers(stream_id: StreamId, fields: HeaderMap) -> Self {
let mut flags = HeadersFlag::default();
flags.set_end_stream();
Headers {
stream_id,
stream_dep: None,
header_block: HeaderBlock {
fields,
is_over_size: false,
pseudo: Pseudo::default(),
},
flags,
}
}
/// Loads the header frame but doesn't actually do HPACK decoding.
///
/// HPACK decoding is done in the `load_hpack` step.
pub fn load(head: Head, mut src: BytesMut) -> Result<(Self, BytesMut), Error> {
let flags = HeadersFlag(head.flag());
let mut pad = 0;
tracing::trace!("loading headers; flags={:?}", flags);
if head.stream_id().is_zero() {
return Err(Error::InvalidStreamId);
}
// Read the padding length
if flags.is_padded() {
if src.is_empty() {
return Err(Error::MalformedMessage);
}
pad = src[0] as usize;
// Drop the padding
let _ = src.split_to(1);
}
// Read the stream dependency
let stream_dep = if flags.is_priority() {
if src.len() < 5 {
return Err(Error::MalformedMessage);
}
let stream_dep = StreamDependency::load(&src[..5])?;
if stream_dep.dependency_id() == head.stream_id() {
return Err(Error::InvalidDependencyId);
}
// Drop the next 5 bytes
let _ = src.split_to(5);
Some(stream_dep)
} else {
None
};
if pad > 0 {
if pad > src.len() {
return Err(Error::TooMuchPadding);
}
let len = src.len() - pad;
src.truncate(len);
}
let headers = Headers {
stream_id: head.stream_id(),
stream_dep,
header_block: HeaderBlock {
fields: HeaderMap::new(),
is_over_size: false,
pseudo: Pseudo::default(),
},
flags,
};
Ok((headers, src))
}
pub fn load_hpack(
&mut self,
src: &mut BytesMut,
max_header_list_size: usize,
decoder: &mut hpack::Decoder,
) -> Result<(), Error> {
self.header_block.load(src, max_header_list_size, decoder)
}
pub fn stream_id(&self) -> StreamId {
self.stream_id
}
pub fn is_end_headers(&self) -> bool {
self.flags.is_end_headers()
}
pub fn set_end_headers(&mut self) {
self.flags.set_end_headers();
}
pub fn is_end_stream(&self) -> bool {
self.flags.is_end_stream()
}
pub fn set_end_stream(&mut self) {
self.flags.set_end_stream()
}
pub fn is_over_size(&self) -> bool {
self.header_block.is_over_size
}
pub fn into_parts(self) -> (Pseudo, HeaderMap) {
(self.header_block.pseudo, self.header_block.fields)
}
#[cfg(feature = "unstable")]
pub fn pseudo_mut(&mut self) -> &mut Pseudo {
&mut self.header_block.pseudo
}
/// Whether it has status 1xx
pub(crate) fn is_informational(&self) -> bool {
self.header_block.pseudo.is_informational()
}
pub fn fields(&self) -> &HeaderMap {
&self.header_block.fields
}
pub fn into_fields(self) -> HeaderMap {
self.header_block.fields
}
pub fn encode(
self,
encoder: &mut hpack::Encoder,
dst: &mut EncodeBuf<'_>,
) -> Option<Continuation> {
// At this point, the `is_end_headers` flag should always be set
debug_assert!(self.flags.is_end_headers());
// Get the HEADERS frame head
let head = self.head();
self.header_block
.into_encoding(encoder)
.encode(&head, dst, |_| {})
}
fn head(&self) -> Head {
Head::new(Kind::Headers, self.flags.into(), self.stream_id)
}
}
impl<T> From<Headers> for Frame<T> {
fn from(src: Headers) -> Self {
Frame::Headers(src)
}
}
impl fmt::Debug for Headers {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let mut builder = f.debug_struct("Headers");
builder
.field("stream_id", &self.stream_id)
.field("flags", &self.flags);
if let Some(ref protocol) = self.header_block.pseudo.protocol {
builder.field("protocol", protocol);
}
if let Some(ref dep) = self.stream_dep {
builder.field("stream_dep", dep);
}
// `fields` and `pseudo` purposefully not included
builder.finish()
}
}
// ===== util =====
#[derive(Debug, PartialEq, Eq)]
pub struct ParseU64Error;
pub fn parse_u64(src: &[u8]) -> Result<u64, ParseU64Error> {
if src.len() > 19 {
// At danger for overflow...
return Err(ParseU64Error);
}
let mut ret = 0;
for &d in src {
if d < b'0' || d > b'9' {
return Err(ParseU64Error);
}
ret *= 10;
ret += (d - b'0') as u64;
}
Ok(ret)
}
// ===== impl PushPromise =====
#[derive(Debug)]
pub enum PushPromiseHeaderError {
InvalidContentLength(Result<u64, ParseU64Error>),
NotSafeAndCacheable,
}
impl PushPromise {
pub fn new(
stream_id: StreamId,
promised_id: StreamId,
pseudo: Pseudo,
fields: HeaderMap,
) -> Self {
PushPromise {
flags: PushPromiseFlag::default(),
header_block: HeaderBlock {
fields,
is_over_size: false,
pseudo,
},
promised_id,
stream_id,
}
}
pub fn validate_request(req: &Request<()>) -> Result<(), PushPromiseHeaderError> {
use PushPromiseHeaderError::*;
// The spec has some requirements for promised request headers
// A promised request "that indicates the presence of a request body
// MUST reset the promised stream with a stream error"
if let Some(content_length) = req.headers().get(header::CONTENT_LENGTH) {
let parsed_length = parse_u64(content_length.as_bytes());
if parsed_length != Ok(0) {
return Err(InvalidContentLength(parsed_length));
}
}
// "The server MUST include a method in the :method pseudo-header field
// that is safe and cacheable"
if !Self::safe_and_cacheable(req.method()) {
return Err(NotSafeAndCacheable);
}
Ok(())
}
fn safe_and_cacheable(method: &Method) -> bool {
method == Method::GET || method == Method::HEAD
}
pub fn fields(&self) -> &HeaderMap {
&self.header_block.fields
}
#[cfg(feature = "unstable")]
pub fn into_fields(self) -> HeaderMap {
self.header_block.fields
}
/// Loads the push promise frame but doesn't actually do HPACK decoding.
///
/// HPACK decoding is done in the `load_hpack` step.
pub fn load(head: Head, mut src: BytesMut) -> Result<(Self, BytesMut), Error> {
let flags = PushPromiseFlag(head.flag());
let mut pad = 0;
if head.stream_id().is_zero() {
return Err(Error::InvalidStreamId);
}
// Read the padding length
if flags.is_padded() {
if src.is_empty() {
return Err(Error::MalformedMessage);
}
// TODO: Ensure payload is sized correctly
pad = src[0] as usize;
// Drop the padding
let _ = src.split_to(1);
}
if src.len() < 5 {
return Err(Error::MalformedMessage);
}
let (promised_id, _) = StreamId::parse(&src[..4]);
// Drop promised_id bytes
let _ = src.split_to(4);
if pad > 0 {
if pad > src.len() {
return Err(Error::TooMuchPadding);
}
let len = src.len() - pad;
src.truncate(len);
}
let frame = PushPromise {
flags,
header_block: HeaderBlock {
fields: HeaderMap::new(),
is_over_size: false,
pseudo: Pseudo::default(),
},
promised_id,
stream_id: head.stream_id(),
};
Ok((frame, src))
}
pub fn load_hpack(
&mut self,
src: &mut BytesMut,
max_header_list_size: usize,
decoder: &mut hpack::Decoder,
) -> Result<(), Error> {
self.header_block.load(src, max_header_list_size, decoder)
}
pub fn stream_id(&self) -> StreamId {
self.stream_id
}
pub fn promised_id(&self) -> StreamId {
self.promised_id
}
pub fn is_end_headers(&self) -> bool {
self.flags.is_end_headers()
}
pub fn set_end_headers(&mut self) {
self.flags.set_end_headers();
}
pub fn is_over_size(&self) -> bool {
self.header_block.is_over_size
}
pub fn encode(
self,
encoder: &mut hpack::Encoder,
dst: &mut EncodeBuf<'_>,
) -> Option<Continuation> {
// At this point, the `is_end_headers` flag should always be set
debug_assert!(self.flags.is_end_headers());
let head = self.head();
let promised_id = self.promised_id;
self.header_block
.into_encoding(encoder)
.encode(&head, dst, |dst| {
dst.put_u32(promised_id.into());
})
}
fn head(&self) -> Head {
Head::new(Kind::PushPromise, self.flags.into(), self.stream_id)
}
/// Consume `self`, returning the parts of the frame
pub fn into_parts(self) -> (Pseudo, HeaderMap) {
(self.header_block.pseudo, self.header_block.fields)
}
}
impl<T> From<PushPromise> for Frame<T> {
fn from(src: PushPromise) -> Self {
Frame::PushPromise(src)
}
}
impl fmt::Debug for PushPromise {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_struct("PushPromise")
.field("stream_id", &self.stream_id)
.field("promised_id", &self.promised_id)
.field("flags", &self.flags)
// `fields` and `pseudo` purposefully not included
.finish()
}
}
// ===== impl Continuation =====
impl Continuation {
fn head(&self) -> Head {
Head::new(Kind::Continuation, END_HEADERS, self.stream_id)
}
pub fn encode(self, dst: &mut EncodeBuf<'_>) -> Option<Continuation> {
// Get the CONTINUATION frame head
let head = self.head();
self.header_block.encode(&head, dst, |_| {})
}
}
// ===== impl Pseudo =====
impl Pseudo {
pub fn request(method: Method, uri: Uri, protocol: Option<Protocol>) -> Self {
let parts = uri::Parts::from(uri);
let mut path = parts
.path_and_query
.map(|v| BytesStr::from(v.as_str()))
.unwrap_or(BytesStr::from_static(""));
match method {
Method::OPTIONS | Method::CONNECT => {}
_ if path.is_empty() => {
path = BytesStr::from_static("/");
}
_ => {}
}
let mut pseudo = Pseudo {
method: Some(method),
scheme: None,
authority: None,
path: Some(path).filter(|p| !p.is_empty()),
protocol,
status: None,
};
// If the URI includes a scheme component, add it to the pseudo headers
//
// TODO: Scheme must be set...
if let Some(scheme) = parts.scheme {
pseudo.set_scheme(scheme);
}
// If the URI includes an authority component, add it to the pseudo
// headers
if let Some(authority) = parts.authority {
pseudo.set_authority(BytesStr::from(authority.as_str()));
}
pseudo
}
pub fn response(status: StatusCode) -> Self {
Pseudo {
method: None,
scheme: None,
authority: None,
path: None,
protocol: None,
status: Some(status),
}
}
#[cfg(feature = "unstable")]
pub fn set_status(&mut self, value: StatusCode) {
self.status = Some(value);
}
pub fn set_scheme(&mut self, scheme: uri::Scheme) {
let bytes_str = match scheme.as_str() {
"http" => BytesStr::from_static("http"),
"https" => BytesStr::from_static("https"),
s => BytesStr::from(s),
};
self.scheme = Some(bytes_str);
}
#[cfg(feature = "unstable")]
pub fn set_protocol(&mut self, protocol: Protocol) {
self.protocol = Some(protocol);
}
pub fn set_authority(&mut self, authority: BytesStr) {
self.authority = Some(authority);
}
/// Whether it has status 1xx
pub(crate) fn is_informational(&self) -> bool {
self.status
.map_or(false, |status| status.is_informational())
}
}
// ===== impl EncodingHeaderBlock =====
impl EncodingHeaderBlock {
fn encode<F>(mut self, head: &Head, dst: &mut EncodeBuf<'_>, f: F) -> Option<Continuation>
where
F: FnOnce(&mut EncodeBuf<'_>),
{
let head_pos = dst.get_ref().len();
// At this point, we don't know how big the h2 frame will be.
// So, we write the head with length 0, then write the body, and
// finally write the length once we know the size.
head.encode(0, dst);
let payload_pos = dst.get_ref().len();
f(dst);
// Now, encode the header payload
let continuation = if self.hpack.len() > dst.remaining_mut() {
dst.put_slice(&self.hpack.split_to(dst.remaining_mut()));
Some(Continuation {
stream_id: head.stream_id(),
header_block: self,
})
} else {
dst.put_slice(&self.hpack);
None
};
// Compute the header block length
let payload_len = (dst.get_ref().len() - payload_pos) as u64;
// Write the frame length
let payload_len_be = payload_len.to_be_bytes();
assert!(payload_len_be[0..5].iter().all(|b| *b == 0));
(dst.get_mut()[head_pos..head_pos + 3]).copy_from_slice(&payload_len_be[5..]);
if continuation.is_some() {
// There will be continuation frames, so the `is_end_headers` flag
// must be unset
debug_assert!(dst.get_ref()[head_pos + 4] & END_HEADERS == END_HEADERS);
dst.get_mut()[head_pos + 4] -= END_HEADERS;
}
continuation
}
}
// ===== impl Iter =====
impl Iterator for Iter {
type Item = hpack::Header<Option<HeaderName>>;
fn next(&mut self) -> Option<Self::Item> {
use crate::hpack::Header::*;
if let Some(ref mut pseudo) = self.pseudo {
if let Some(method) = pseudo.method.take() {
return Some(Method(method));
}
if let Some(scheme) = pseudo.scheme.take() {
return Some(Scheme(scheme));
}
if let Some(authority) = pseudo.authority.take() {
return Some(Authority(authority));
}
if let Some(path) = pseudo.path.take() {
return Some(Path(path));
}
if let Some(protocol) = pseudo.protocol.take() {
return Some(Protocol(protocol));
}
if let Some(status) = pseudo.status.take() {
return Some(Status(status));
}
}
self.pseudo = None;
self.fields
.next()
.map(|(name, value)| Field { name, value })
}
}
// ===== impl HeadersFlag =====
impl HeadersFlag {
pub fn empty() -> HeadersFlag {
HeadersFlag(0)
}
pub fn load(bits: u8) -> HeadersFlag {
HeadersFlag(bits & ALL)
}
pub fn is_end_stream(&self) -> bool {
self.0 & END_STREAM == END_STREAM
}
pub fn set_end_stream(&mut self) {
self.0 |= END_STREAM;
}
pub fn is_end_headers(&self) -> bool {
self.0 & END_HEADERS == END_HEADERS
}
pub fn set_end_headers(&mut self) {
self.0 |= END_HEADERS;
}
pub fn is_padded(&self) -> bool {
self.0 & PADDED == PADDED
}
pub fn is_priority(&self) -> bool {
self.0 & PRIORITY == PRIORITY
}
}
impl Default for HeadersFlag {
/// Returns a `HeadersFlag` value with `END_HEADERS` set.
fn default() -> Self {
HeadersFlag(END_HEADERS)
}
}
impl From<HeadersFlag> for u8 {
fn from(src: HeadersFlag) -> u8 {
src.0
}
}
impl fmt::Debug for HeadersFlag {
fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
util::debug_flags(fmt, self.0)
.flag_if(self.is_end_headers(), "END_HEADERS")
.flag_if(self.is_end_stream(), "END_STREAM")
.flag_if(self.is_padded(), "PADDED")
.flag_if(self.is_priority(), "PRIORITY")
.finish()
}
}
// ===== impl PushPromiseFlag =====
impl PushPromiseFlag {
pub fn empty() -> PushPromiseFlag {
PushPromiseFlag(0)
}
pub fn load(bits: u8) -> PushPromiseFlag {
PushPromiseFlag(bits & ALL)
}
pub fn is_end_headers(&self) -> bool {
self.0 & END_HEADERS == END_HEADERS
}
pub fn set_end_headers(&mut self) {
self.0 |= END_HEADERS;
}
pub fn is_padded(&self) -> bool {
self.0 & PADDED == PADDED
}
}
impl Default for PushPromiseFlag {
/// Returns a `PushPromiseFlag` value with `END_HEADERS` set.
fn default() -> Self {
PushPromiseFlag(END_HEADERS)
}
}
impl From<PushPromiseFlag> for u8 {
fn from(src: PushPromiseFlag) -> u8 {
src.0
}
}
impl fmt::Debug for PushPromiseFlag {
fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
util::debug_flags(fmt, self.0)
.flag_if(self.is_end_headers(), "END_HEADERS")
.flag_if(self.is_padded(), "PADDED")
.finish()
}
}
// ===== HeaderBlock =====
impl HeaderBlock {
fn load(
&mut self,
src: &mut BytesMut,
max_header_list_size: usize,
decoder: &mut hpack::Decoder,
) -> Result<(), Error> {
let mut reg = !self.fields.is_empty();
let mut malformed = false;
let mut headers_size = self.calculate_header_list_size();
macro_rules! set_pseudo {
($field:ident, $val:expr) => {{
if reg {
tracing::trace!("load_hpack; header malformed -- pseudo not at head of block");
malformed = true;
} else if self.pseudo.$field.is_some() {
tracing::trace!("load_hpack; header malformed -- repeated pseudo");
malformed = true;
} else {
let __val = $val;
headers_size +=
decoded_header_size(stringify!($field).len() + 1, __val.as_str().len());
if headers_size < max_header_list_size {
self.pseudo.$field = Some(__val);
} else if !self.is_over_size {
tracing::trace!("load_hpack; header list size over max");
self.is_over_size = true;
}
}
}};
}
let mut cursor = Cursor::new(src);
// If the header frame is malformed, we still have to continue decoding
// the headers. A malformed header frame is a stream level error, but
// the hpack state is connection level. In order to maintain correct
// state for other streams, the hpack decoding process must complete.
let res = decoder.decode(&mut cursor, |header| {
use crate::hpack::Header::*;
match header {
Field { name, value } => {
// Connection level header fields are not supported and must
// result in a protocol error.
if name == header::CONNECTION
|| name == header::TRANSFER_ENCODING
|| name == header::UPGRADE
|| name == "keep-alive"
|| name == "proxy-connection"
{
tracing::trace!("load_hpack; connection level header");
malformed = true;
} else if name == header::TE && value != "trailers" {
tracing::trace!(
"load_hpack; TE header not set to trailers; val={:?}",
value
);
malformed = true;
} else {
reg = true;
headers_size += decoded_header_size(name.as_str().len(), value.len());
if headers_size < max_header_list_size {
self.fields.append(name, value);
} else if !self.is_over_size {
tracing::trace!("load_hpack; header list size over max");
self.is_over_size = true;
}
}
}
Authority(v) => set_pseudo!(authority, v),
Method(v) => set_pseudo!(method, v),
Scheme(v) => set_pseudo!(scheme, v),
Path(v) => set_pseudo!(path, v),
Protocol(v) => set_pseudo!(protocol, v),
Status(v) => set_pseudo!(status, v),
}
});
if let Err(e) = res {
tracing::trace!("hpack decoding error; err={:?}", e);
return Err(e.into());
}
if malformed {
tracing::trace!("malformed message");
return Err(Error::MalformedMessage);
}
Ok(())
}
fn into_encoding(self, encoder: &mut hpack::Encoder) -> EncodingHeaderBlock {
let mut hpack = BytesMut::new();
let headers = Iter {
pseudo: Some(self.pseudo),
fields: self.fields.into_iter(),
};
encoder.encode(headers, &mut hpack);
EncodingHeaderBlock {
hpack: hpack.freeze(),
}
}
/// Calculates the size of the currently decoded header list.
///
///
/// > The value is based on the uncompressed size of header fields,
/// > including the length of the name and value in octets plus an
/// > overhead of 32 octets for each header field.
fn calculate_header_list_size(&self) -> usize {
macro_rules! pseudo_size {
($name:ident) => {{
self.pseudo
.$name
.as_ref()
.map(|m| decoded_header_size(stringify!($name).len() + 1, m.as_str().len()))
.unwrap_or(0)
}};
}
pseudo_size!(method)
+ pseudo_size!(scheme)
+ pseudo_size!(status)
+ pseudo_size!(authority)
+ pseudo_size!(path)
+ self
.fields
.iter()
.map(|(name, value)| decoded_header_size(name.as_str().len(), value.len()))
.sum::<usize>()
}
}
fn decoded_header_size(name: usize, value: usize) -> usize {
name + value + 32
}
#[cfg(test)]
mod test {
use std::iter::FromIterator;
use http::HeaderValue;
use super::*;
use crate::frame;
use crate::hpack::{huffman, Encoder};
#[test]
fn test_nameless_header_at_resume() {
let mut encoder = Encoder::default();
let mut dst = BytesMut::new();
let headers = Headers::new(
StreamId::ZERO,
Default::default(),
HeaderMap::from_iter(vec![
(
HeaderName::from_static("hello"),
HeaderValue::from_static("world"),
),
(
HeaderName::from_static("hello"),
HeaderValue::from_static("zomg"),
),
(
HeaderName::from_static("hello"),
HeaderValue::from_static("sup"),
),
]),
);
let continuation = headers
.encode(&mut encoder, &mut (&mut dst).limit(frame::HEADER_LEN + 8))
.unwrap();
assert_eq!(17, dst.len());
assert_eq!([0, 0, 8, 1, 0, 0, 0, 0, 0], &dst[0..9]);
assert_eq!(&[0x40, 0x80 | 4], &dst[9..11]);
assert_eq!("hello", huff_decode(&dst[11..15]));
assert_eq!(0x80 | 4, dst[15]);
let mut world = dst[16..17].to_owned();
dst.clear();
assert!(continuation
.encode(&mut (&mut dst).limit(frame::HEADER_LEN + 16))
.is_none());
world.extend_from_slice(&dst[9..12]);
assert_eq!("world", huff_decode(&world));
assert_eq!(24, dst.len());
assert_eq!([0, 0, 15, 9, 4, 0, 0, 0, 0], &dst[0..9]);
// // Next is not indexed
assert_eq!(&[15, 47, 0x80 | 3], &dst[12..15]);
assert_eq!("zomg", huff_decode(&dst[15..18]));
assert_eq!(&[15, 47, 0x80 | 3], &dst[18..21]);
assert_eq!("sup", huff_decode(&dst[21..]));
}
fn huff_decode(src: &[u8]) -> BytesMut {
let mut buf = BytesMut::new();
huffman::decode(src, &mut buf).unwrap()
}
}