begin work on server

1 files changed, 232 insertions, 0 deletions

diff --git a/src/hex.rs b/src/hex.rs
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+++ b/src/hex.rs
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+// Copyright 2013-2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+//! Hex binary-to-text encoding
+
+pub use self::FromHexError::*;
+
+use std::fmt;
+use std::error;
+
+/// A trait for converting a value to hexadecimal encoding
+pub trait ToHex {
+    /// Converts the value of `self` to a hex value, returning the owned
+    /// string.
+    fn to_hex(&self) -> String;
+}
+
+const CHARS: &'static [u8] = b"0123456789abcdef";
+
+impl ToHex for [u8] {
+    /// Turn a vector of `u8` bytes into a hexadecimal string.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(rustc_private)]
+    ///
+    /// extern crate serialize;
+    /// use serialize::hex::ToHex;
+    ///
+    /// fn main () {
+    ///     let str = [52,32].to_hex();
+    ///     println!("{}", str);
+    /// }
+    /// ```
+    fn to_hex(&self) -> String {
+        let mut v = Vec::with_capacity(self.len() * 2);
+        for &byte in self {
+            v.push(CHARS[(byte >> 4) as usize]);
+            v.push(CHARS[(byte & 0xf) as usize]);
+        }
+
+        unsafe {
+            String::from_utf8_unchecked(v)
+        }
+    }
+}
+
+/// A trait for converting hexadecimal encoded values
+pub trait FromHex {
+    /// Converts the value of `self`, interpreted as hexadecimal encoded data,
+    /// into an owned vector of bytes, returning the vector.
+    fn from_hex(&self) -> Result<Vec<u8>, FromHexError>;
+}
+
+/// Errors that can occur when decoding a hex encoded string
+#[derive(Copy, Clone, Debug)]
+pub enum FromHexError {
+    /// The input contained a character not part of the hex format
+    InvalidHexCharacter(char, usize),
+    /// The input had an invalid length
+    InvalidHexLength,
+}
+
+impl fmt::Display for FromHexError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match *self {
+            InvalidHexCharacter(ch, idx) =>
+                write!(f, "Invalid character '{}' at position {}", ch, idx),
+            InvalidHexLength => write!(f, "Invalid input length"),
+        }
+    }
+}
+
+impl error::Error for FromHexError {
+    fn description(&self) -> &str {
+        match *self {
+            InvalidHexCharacter(..) => "invalid character",
+            InvalidHexLength => "invalid length",
+        }
+    }
+}
+
+
+impl FromHex for str {
+    /// Convert any hexadecimal encoded string (literal, `@`, `&`, or `~`)
+    /// to the byte values it encodes.
+    ///
+    /// You can use the `String::from_utf8` function to turn a
+    /// `Vec<u8>` into a string with characters corresponding to those values.
+    ///
+    /// # Examples
+    ///
+    /// This converts a string literal to hexadecimal and back.
+    ///
+    /// ```
+    /// #![feature(rustc_private)]
+    ///
+    /// extern crate serialize;
+    /// use serialize::hex::{FromHex, ToHex};
+    ///
+    /// fn main () {
+    ///     let hello_str = "Hello, World".as_bytes().to_hex();
+    ///     println!("{}", hello_str);
+    ///     let bytes = hello_str.from_hex().unwrap();
+    ///     println!("{:?}", bytes);
+    ///     let result_str = String::from_utf8(bytes).unwrap();
+    ///     println!("{}", result_str);
+    /// }
+    /// ```
+    fn from_hex(&self) -> Result<Vec<u8>, FromHexError> {
+        // This may be an overestimate if there is any whitespace
+        let mut b = Vec::with_capacity(self.len() / 2);
+        let mut modulus = 0;
+        let mut buf = 0;
+
+        for (idx, byte) in self.bytes().enumerate() {
+            buf <<= 4;
+
+            match byte {
+                b'A'...b'F' => buf |= byte - b'A' + 10,
+                b'a'...b'f' => buf |= byte - b'a' + 10,
+                b'0'...b'9' => buf |= byte - b'0',
+                b' '|b'\r'|b'\n'|b'\t' => {
+                    buf >>= 4;
+                    continue
+                }
+                _ => {
+                    let ch = self[idx..].chars().next().unwrap();
+                    return Err(InvalidHexCharacter(ch, idx))
+                }
+            }
+
+            modulus += 1;
+            if modulus == 2 {
+                modulus = 0;
+                b.push(buf);
+            }
+        }
+
+        match modulus {
+            0 => Ok(b.into_iter().collect()),
+            _ => Err(InvalidHexLength),
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    extern crate test;
+    use self::test::Bencher;
+    use hex::{FromHex, ToHex};
+
+    #[test]
+    pub fn test_to_hex() {
+        assert_eq!("foobar".as_bytes().to_hex(), "666f6f626172");
+    }
+
+    #[test]
+    pub fn test_from_hex_okay() {
+        assert_eq!("666f6f626172".from_hex().unwrap(),
+                b"foobar");
+        assert_eq!("666F6F626172".from_hex().unwrap(),
+                b"foobar");
+    }
+
+    #[test]
+    pub fn test_from_hex_odd_len() {
+        assert!("666".from_hex().is_err());
+        assert!("66 6".from_hex().is_err());
+    }
+
+    #[test]
+    pub fn test_from_hex_invalid_char() {
+        assert!("66y6".from_hex().is_err());
+    }
+
+    #[test]
+    pub fn test_from_hex_ignores_whitespace() {
+        assert_eq!("666f 6f6\r\n26172 ".from_hex().unwrap(),
+                b"foobar");
+    }
+
+    #[test]
+    pub fn test_to_hex_all_bytes() {
+        for i in 0..256 {
+            assert_eq!([i as u8].to_hex(), format!("{:02x}", i as usize));
+        }
+    }
+
+    #[test]
+    pub fn test_from_hex_all_bytes() {
+        for i in 0..256 {
+            let ii: &[u8] = &[i as u8];
+            assert_eq!(format!("{:02x}", i as usize).from_hex()
+                                                .unwrap(),
+                    ii);
+            assert_eq!(format!("{:02X}", i as usize).from_hex()
+                                                .unwrap(),
+                    ii);
+        }
+    }
+
+    #[bench]
+    pub fn bench_to_hex(b: &mut Bencher) {
+        let s = "イロハニホヘト チリヌルヲ ワカヨタレソ ツネナラム \
+                ウヰノオクヤマ ケフコエテ アサキユメミシ ヱヒモセスン";
+        b.iter(|| {
+            s.as_bytes().to_hex();
+        });
+        b.bytes = s.len() as u64;
+    }
+
+    #[bench]
+    pub fn bench_from_hex(b: &mut Bencher) {
+        let s = "イロハニホヘト チリヌルヲ ワカヨタレソ ツネナラム \
+                ウヰノオクヤマ ケフコエテ アサキユメミシ ヱヒモセスン";
+        let sb = s.as_bytes().to_hex();
+        b.iter(|| {
+            sb.from_hex().unwrap();
+        });
+        b.bytes = sb.len() as u64;
+    }
+}
+