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

use crate::codec::encoder::Encoder;
use crate::codec::framed_impl::{FramedImpl, WriteFrame};

use futures_core::Stream;
use tokio::io::AsyncWrite;

use bytes::BytesMut;
use futures_sink::Sink;
use pin_project_lite::pin_project;
use std::fmt;
use std::io;
use std::pin::Pin;
use std::task::{Context, Poll};

pin_project! {
    /// A [`Sink`] of frames encoded to an `AsyncWrite`.
    ///
    /// [`Sink`]: futures_sink::Sink
    pub struct FramedWrite<T, E> {
        #[pin]
        inner: FramedImpl<T, E, WriteFrame>,
    }
}

impl<T, E> FramedWrite<T, E>
where
    T: AsyncWrite,
{
    /// Creates a new `FramedWrite` with the given `encoder`.
    pub fn new(inner: T, encoder: E) -> FramedWrite<T, E> {
        FramedWrite {
            inner: FramedImpl {
                inner,
                codec: encoder,
                state: WriteFrame::default(),
            },
        }
    }
}

impl<T, E> FramedWrite<T, E> {
    /// Returns a reference to the underlying I/O stream wrapped by
    /// `FramedWrite`.
    ///
    /// Note that care should be taken to not tamper with the underlying stream
    /// of data coming in as it may corrupt the stream of frames otherwise
    /// being worked with.
    pub fn get_ref(&self) -> &T {
        &self.inner.inner
    }

    /// Returns a mutable reference to the underlying I/O stream wrapped by
    /// `FramedWrite`.
    ///
    /// Note that care should be taken to not tamper with the underlying stream
    /// of data coming in as it may corrupt the stream of frames otherwise
    /// being worked with.
    pub fn get_mut(&mut self) -> &mut T {
        &mut self.inner.inner
    }

    /// Returns a pinned mutable reference to the underlying I/O stream wrapped by
    /// `FramedWrite`.
    ///
    /// Note that care should be taken to not tamper with the underlying stream
    /// of data coming in as it may corrupt the stream of frames otherwise
    /// being worked with.
    pub fn get_pin_mut(self: Pin<&mut Self>) -> Pin<&mut T> {
        self.project().inner.project().inner
    }

    /// Consumes the `FramedWrite`, returning its underlying I/O stream.
    ///
    /// Note that care should be taken to not tamper with the underlying stream
    /// of data coming in as it may corrupt the stream of frames otherwise
    /// being worked with.
    pub fn into_inner(self) -> T {
        self.inner.inner
    }

    /// Returns a reference to the underlying encoder.
    pub fn encoder(&self) -> &E {
        &self.inner.codec
    }

    /// Returns a mutable reference to the underlying encoder.
    pub fn encoder_mut(&mut self) -> &mut E {
        &mut self.inner.codec
    }

    /// Returns a reference to the write buffer.
    pub fn write_buffer(&self) -> &BytesMut {
        &self.inner.state.buffer
    }

    /// Returns a mutable reference to the write buffer.
    pub fn write_buffer_mut(&mut self) -> &mut BytesMut {
        &mut self.inner.state.buffer
    }
}

// This impl just defers to the underlying FramedImpl
impl<T, I, E> Sink<I> for FramedWrite<T, E>
where
    T: AsyncWrite,
    E: Encoder<I>,
    E::Error: From<io::Error>,
{
    type Error = E::Error;

    fn poll_ready(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
        self.project().inner.poll_ready(cx)
    }

    fn start_send(self: Pin<&mut Self>, item: I) -> Result<(), Self::Error> {
        self.project().inner.start_send(item)
    }

    fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
        self.project().inner.poll_flush(cx)
    }

    fn poll_close(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
        self.project().inner.poll_close(cx)
    }
}

// This impl just defers to the underlying T: Stream
impl<T, D> Stream for FramedWrite<T, D>
where
    T: Stream,
{
    type Item = T::Item;

    fn poll_next(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
        self.project().inner.project().inner.poll_next(cx)
    }
}

impl<T, U> fmt::Debug for FramedWrite<T, U>
where
    T: fmt::Debug,
    U: fmt::Debug,
{
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("FramedWrite")
            .field("inner", &self.get_ref())
            .field("encoder", &self.encoder())
            .field("buffer", &self.inner.state.buffer)
            .finish()
    }
}