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

//! Error and Result module.
use std::error::Error as StdError;
use std::fmt;
use std::str::Utf8Error;
use std::string::FromUtf8Error;

use httparse;

use self::Error::{
    Method,
    Version,
    Header,
    Status,
    TooLarge,
    Utf8
};

/// Result type often returned from methods that can have hyper `Error`s.
pub type Result<T> = ::std::result::Result<T, Error>;

/// Errors while parsing headers and associated types.
#[derive(Debug)]
pub enum Error {
    /// An invalid `Method`, such as `GE,T`.
    Method,
    /// An invalid `HttpVersion`, such as `HTP/1.1`
    Version,
    /// An invalid `Header`.
    Header,
    /// A message head is too large to be reasonable.
    TooLarge,
    /// An invalid `Status`, such as `1337 ELITE`.
    Status,
    /// Parsing a field as string failed.
    Utf8(Utf8Error),

    #[doc(hidden)]
    __Nonexhaustive(Void)
}

#[doc(hidden)]
pub struct Void(());

impl fmt::Debug for Void {
    fn fmt(&self, _: &mut fmt::Formatter) -> fmt::Result {
        unreachable!()
    }
}

impl fmt::Display for Error {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        match *self {
            Utf8(ref e) => fmt::Display::fmt(e, f),
            ref e => f.write_str(e.description()),
        }
    }
}

impl StdError for Error {
    fn description(&self) -> &str {
        match *self {
            Method => "invalid Method specified",
            Version => "invalid HTTP version specified",
            Header => "invalid Header provided",
            TooLarge => "message head is too large",
            Status => "invalid Status provided",
            Utf8(ref e) => e.description(),
            Error::__Nonexhaustive(..) =>  unreachable!(),
        }
    }

    fn cause(&self) -> Option<&dyn StdError> {
        match *self {
            Utf8(ref error) => Some(error),
            Error::__Nonexhaustive(..) =>  unreachable!(),
            _ => None,
        }
    }
}

impl From<Utf8Error> for Error {
    fn from(err: Utf8Error) -> Error {
        Utf8(err)
    }
}

impl From<FromUtf8Error> for Error {
    fn from(err: FromUtf8Error) -> Error {
        Utf8(err.utf8_error())
    }
}

impl From<httparse::Error> for Error {
    fn from(err: httparse::Error) -> Error {
        match err {
            httparse::Error::HeaderName |
            httparse::Error::HeaderValue |
            httparse::Error::NewLine |
            httparse::Error::Token => Header,
            httparse::Error::Status => Status,
            httparse::Error::TooManyHeaders => TooLarge,
            httparse::Error::Version => Version,
        }
    }
}

#[doc(hidden)]
trait AssertSendSync: Send + Sync + 'static {}
#[doc(hidden)]
impl AssertSendSync for Error {}

#[cfg(test)]
mod tests {
    use std::error::Error as StdError;
    use httparse;
    use super::Error;
    use super::Error::*;

    macro_rules! from {
        ($from:expr => $error:pat) => {
            match Error::from($from) {
                e @ $error => {
                    assert!(e.description().len() >= 5);
                } ,
                e => panic!("{:?}", e)
            }
        }
    }

    #[test]
    fn test_from() {
        from!(httparse::Error::HeaderName => Header);
        from!(httparse::Error::HeaderName => Header);
        from!(httparse::Error::HeaderValue => Header);
        from!(httparse::Error::NewLine => Header);
        from!(httparse::Error::Status => Status);
        from!(httparse::Error::Token => Header);
        from!(httparse::Error::TooManyHeaders => TooLarge);
        from!(httparse::Error::Version => Version);
    }
}