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

use super::{read_marker, RmpRead, ValueReadError};
use crate::Marker;

/// Attempts to read exactly 3 bytes from the given reader and interpret them as a fixext1 type
/// with data attached.
///
/// According to the MessagePack specification, a fixext1 stores an integer and a byte array whose
/// length is 1 byte. Its marker byte is `0xd4`.
///
/// Note, that this function copies a byte array from the reader to the output `u8` variable.
///
/// # Errors
///
/// This function will return `ValueReadError` on any I/O error while reading either the marker or
/// the data.
///
/// # Note
///
/// This function will silently retry on every EINTR received from the underlying `Read` until
/// successful read.
pub fn read_fixext1<R: RmpRead>(rd: &mut R) -> Result<(i8, u8), ValueReadError<R::Error>> {
    match read_marker(rd)? {
        Marker::FixExt1 => {
            let ty = rd.read_data_i8()?;
            let data = rd.read_data_u8()?;
            Ok((ty, data))
        }
        marker => Err(ValueReadError::TypeMismatch(marker)),
    }
}

/// Attempts to read exactly 4 bytes from the given reader and interpret them as a fixext2 type
/// with data attached.
///
/// According to the MessagePack specification, a fixext2 stores an integer and a byte array whose
/// length is 2 bytes. Its marker byte is `0xd5`.
///
/// Note, that this function copies a byte array from the reader to the output buffer, which is
/// unlikely if you want zero-copy functionality.
///
/// # Errors
///
/// This function will return `ValueReadError` on any I/O error while reading either the marker or
/// the data.
pub fn read_fixext2<R: RmpRead>(rd: &mut R) -> Result<(i8, [u8; 2]), ValueReadError<R::Error>> {
    match read_marker(rd)? {
        Marker::FixExt2 => {
            let mut buf = [0; 2];
            read_fixext_data(rd, &mut buf).map(|ty| (ty, buf))
        }
        marker => Err(ValueReadError::TypeMismatch(marker)),
    }
}

/// Attempts to read exactly 6 bytes from the given reader and interpret them as a fixext4 type
/// with data attached.
///
/// According to the MessagePack specification, a fixext4 stores an integer and a byte array whose
/// length is 4 bytes. Its marker byte is `0xd6`.
///
/// Note, that this function copies a byte array from the reader to the output buffer, which is
/// unlikely if you want zero-copy functionality.
///
/// # Errors
///
/// This function will return `ValueReadError` on any I/O error while reading either the marker or
/// the data.
pub fn read_fixext4<R: RmpRead>(rd: &mut R) -> Result<(i8, [u8; 4]), ValueReadError<R::Error>> {
    match read_marker(rd)? {
        Marker::FixExt4 => {
            let mut buf = [0; 4];
            read_fixext_data(rd, &mut buf).map(|ty| (ty, buf))
        }
        marker => Err(ValueReadError::TypeMismatch(marker)),
    }
}

/// Attempts to read exactly 10 bytes from the given reader and interpret them as a fixext8 type
/// with data attached.
///
/// According to the MessagePack specification, a fixext8 stores an integer and a byte array whose
/// length is 8 bytes. Its marker byte is `0xd7`.
///
/// Note, that this function copies a byte array from the reader to the output buffer, which is
/// unlikely if you want zero-copy functionality.
///
/// # Errors
///
/// This function will return `ValueReadError` on any I/O error while reading either the marker or
/// the data.
pub fn read_fixext8<R: RmpRead>(rd: &mut R) -> Result<(i8, [u8; 8]), ValueReadError<R::Error>> {
    match read_marker(rd)? {
        Marker::FixExt8 => {
            let mut buf = [0; 8];
            read_fixext_data(rd, &mut buf).map(|ty| (ty, buf))
        }
        marker => Err(ValueReadError::TypeMismatch(marker)),
    }
}

/// Attempts to read exactly 18 bytes from the given reader and interpret them as a fixext16 type
/// with data attached.
///
/// According to the MessagePack specification, a fixext16 stores an integer and a byte array whose
/// length is 16 bytes. Its marker byte is `0xd8`.
///
/// Note, that this function copies a byte array from the reader to the output buffer, which is
/// unlikely if you want zero-copy functionality.
///
/// # Errors
///
/// This function will return `ValueReadError` on any I/O error while reading either the marker or
/// the data.
pub fn read_fixext16<R: RmpRead>(rd: &mut R) -> Result<(i8, [u8; 16]), ValueReadError<R::Error>> {
    match read_marker(rd)? {
        Marker::FixExt16 => {
            let mut buf = [0; 16];
            read_fixext_data(rd, &mut buf).map(|ty| (ty, buf))
        }
        marker => Err(ValueReadError::TypeMismatch(marker)),
    }
}

fn read_fixext_data<R: RmpRead>(rd: &mut R, buf: &mut [u8]) -> Result<i8, ValueReadError<R::Error>> {
    let id = rd.read_data_i8()?;
    match rd.read_exact_buf(buf) {
        Ok(()) => Ok(id),
        Err(err) => Err(ValueReadError::InvalidDataRead(err)),
    }
}

/// Extension type meta information.
///
/// Extension represents a tuple of type information and a byte array where type information is an
/// integer whose meaning is defined by applications.
///
/// Applications can assign 0 to 127 to store application-specific type information.
///
/// # Note
///
/// MessagePack reserves -1 to -128 for future extension to add predefined types which will be
/// described in separated documents.
#[derive(Debug, PartialEq)]
pub struct ExtMeta {
    /// Type information.
    pub typeid: i8,
    /// Byte array size.
    pub size: u32,
}

pub fn read_ext_meta<R: RmpRead>(rd: &mut R) -> Result<ExtMeta, ValueReadError<R::Error>> {
    let size = match read_marker(rd)? {
        Marker::FixExt1 => 1,
        Marker::FixExt2 => 2,
        Marker::FixExt4 => 4,
        Marker::FixExt8 => 8,
        Marker::FixExt16 => 16,
        Marker::Ext8 => u32::from(rd.read_data_u8()?),
        Marker::Ext16 => u32::from(rd.read_data_u16()?),
        Marker::Ext32 => rd.read_data_u32()?,
        marker => return Err(ValueReadError::TypeMismatch(marker)),
    };

    let ty = rd.read_data_i8()?;
    let meta = ExtMeta { typeid: ty, size };

    Ok(meta)
}