1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171

use crate::hpack;

use bytes::Bytes;

use std::fmt;

/// A helper macro that unpacks a sequence of 4 bytes found in the buffer with
/// the given identifier, starting at the given offset, into the given integer
/// type. Obviously, the integer type should be able to support at least 4
/// bytes.
///
/// # Examples
///
/// ```ignore
/// # // We ignore this doctest because the macro is not exported.
/// let buf: [u8; 4] = [0, 0, 0, 1];
/// assert_eq!(1u32, unpack_octets_4!(buf, 0, u32));
/// ```
macro_rules! unpack_octets_4 {
    // TODO: Get rid of this macro
    ($buf:expr, $offset:expr, $tip:ty) => {
        (($buf[$offset + 0] as $tip) << 24)
            | (($buf[$offset + 1] as $tip) << 16)
            | (($buf[$offset + 2] as $tip) << 8)
            | (($buf[$offset + 3] as $tip) << 0)
    };
}

#[cfg(test)]
mod tests {
    #[test]
    fn test_unpack_octets_4() {
        let buf: [u8; 4] = [0, 0, 0, 1];
        assert_eq!(1u32, unpack_octets_4!(buf, 0, u32));
    }
}

mod data;
mod go_away;
mod head;
mod headers;
mod ping;
mod priority;
mod reason;
mod reset;
mod settings;
mod stream_id;
mod util;
mod window_update;

pub use self::data::Data;
pub use self::go_away::GoAway;
pub use self::head::{Head, Kind};
pub use self::headers::{
    parse_u64, Continuation, Headers, Pseudo, PushPromise, PushPromiseHeaderError,
};
pub use self::ping::Ping;
pub use self::priority::{Priority, StreamDependency};
pub use self::reason::Reason;
pub use self::reset::Reset;
pub use self::settings::Settings;
pub use self::stream_id::{StreamId, StreamIdOverflow};
pub use self::window_update::WindowUpdate;

#[cfg(feature = "unstable")]
pub use crate::hpack::BytesStr;

// Re-export some constants

pub use self::settings::{
    DEFAULT_INITIAL_WINDOW_SIZE, DEFAULT_MAX_FRAME_SIZE, DEFAULT_SETTINGS_HEADER_TABLE_SIZE,
    MAX_INITIAL_WINDOW_SIZE, MAX_MAX_FRAME_SIZE,
};

pub type FrameSize = u32;

pub const HEADER_LEN: usize = 9;

#[derive(Eq, PartialEq)]
pub enum Frame<T = Bytes> {
    Data(Data<T>),
    Headers(Headers),
    Priority(Priority),
    PushPromise(PushPromise),
    Settings(Settings),
    Ping(Ping),
    GoAway(GoAway),
    WindowUpdate(WindowUpdate),
    Reset(Reset),
}

impl<T> Frame<T> {
    pub fn map<F, U>(self, f: F) -> Frame<U>
    where
        F: FnOnce(T) -> U,
    {
        use self::Frame::*;

        match self {
            Data(frame) => frame.map(f).into(),
            Headers(frame) => frame.into(),
            Priority(frame) => frame.into(),
            PushPromise(frame) => frame.into(),
            Settings(frame) => frame.into(),
            Ping(frame) => frame.into(),
            GoAway(frame) => frame.into(),
            WindowUpdate(frame) => frame.into(),
            Reset(frame) => frame.into(),
        }
    }
}

impl<T> fmt::Debug for Frame<T> {
    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
        use self::Frame::*;

        match *self {
            Data(ref frame) => fmt::Debug::fmt(frame, fmt),
            Headers(ref frame) => fmt::Debug::fmt(frame, fmt),
            Priority(ref frame) => fmt::Debug::fmt(frame, fmt),
            PushPromise(ref frame) => fmt::Debug::fmt(frame, fmt),
            Settings(ref frame) => fmt::Debug::fmt(frame, fmt),
            Ping(ref frame) => fmt::Debug::fmt(frame, fmt),
            GoAway(ref frame) => fmt::Debug::fmt(frame, fmt),
            WindowUpdate(ref frame) => fmt::Debug::fmt(frame, fmt),
            Reset(ref frame) => fmt::Debug::fmt(frame, fmt),
        }
    }
}

/// Errors that can occur during parsing an HTTP/2 frame.
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum Error {
    /// A length value other than 8 was set on a PING message.
    BadFrameSize,

    /// The padding length was larger than the frame-header-specified
    /// length of the payload.
    TooMuchPadding,

    /// An invalid setting value was provided
    InvalidSettingValue,

    /// An invalid window update value
    InvalidWindowUpdateValue,

    /// The payload length specified by the frame header was not the
    /// value necessary for the specific frame type.
    InvalidPayloadLength,

    /// Received a payload with an ACK settings frame
    InvalidPayloadAckSettings,

    /// An invalid stream identifier was provided.
    ///
    /// This is returned if a SETTINGS or PING frame is received with a stream
    /// identifier other than zero.
    InvalidStreamId,

    /// A request or response is malformed.
    MalformedMessage,

    /// An invalid stream dependency ID was provided
    ///
    /// This is returned if a HEADERS or PRIORITY frame is received with an
    /// invalid stream identifier.
    InvalidDependencyId,

    /// Failed to perform HPACK decoding
    Hpack(hpack::DecoderError),
}