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
172
173
174
175
176
177
//! Fixed-size hashes

use std::{fmt, ops, cmp, str};
use hex::{ToHex, FromHex, FromHexError};
use std::hash::{Hash, Hasher};

macro_rules! impl_hash {
	($name: ident, $size: expr) => {
		#[repr(C)]
		pub struct $name([u8; $size]);

		impl Default for $name {
			fn default() -> Self {
				$name([0u8; $size])
			}
		}

		impl AsRef<$name> for $name {
			fn as_ref(&self) -> &$name {
				self
			}
		}

		impl Clone for $name {
			fn clone(&self) -> Self {
				let mut result = Self::default();
				result.copy_from_slice(&self.0);
				result
			}
		}

		impl From<[u8; $size]> for $name {
			fn from(h: [u8; $size]) -> Self {
				$name(h)
			}
		}

		impl From<$name> for [u8; $size] {
			fn from(h: $name) -> Self {
				h.0
			}
		}

		impl<'a> From<&'a [u8]> for $name {
			fn from(slc: &[u8]) -> Self {
				let mut inner = [0u8; $size];
				inner[..].clone_from_slice(&slc[0..$size]);
				$name(inner)
			}
		}

		impl From<&'static str> for $name {
			fn from(s: &'static str) -> Self {
				s.parse().unwrap()
			}
		}

		impl From<u8> for $name {
			fn from(v: u8) -> Self {
				let mut result = Self::default();
				result.0[0] = v;
				result
			}
		}

		impl str::FromStr for $name {
			type Err = FromHexError;

			fn from_str(s: &str) -> Result<Self, Self::Err> {
				let vec: Vec<u8> = try!(s.from_hex());
				match vec.len() {
					$size => {
						let mut result = [0u8; $size];
						result.copy_from_slice(&vec);
						Ok($name(result))
					},
					_ => Err(FromHexError::InvalidHexLength)
				}
			}
		}

		impl fmt::Debug for $name {
			fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
				f.write_str(&self.0.to_hex::<String>())
			}
		}

		impl fmt::Display for $name {
			fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
				f.write_str(&self.0.to_hex::<String>())
			}
		}

		impl ops::Deref for $name {
			type Target = [u8; $size];

			fn deref(&self) -> &Self::Target {
				&self.0
			}
		}

		impl ops::DerefMut for $name {
			fn deref_mut(&mut self) -> &mut Self::Target {
				&mut self.0
			}
		}

		impl cmp::PartialEq for $name {
			fn eq(&self, other: &Self) -> bool {
				let self_ref: &[u8] = &self.0;
				let other_ref: &[u8] = &other.0;
				self_ref == other_ref
			}
		}

		impl cmp::PartialOrd for $name {
			fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> {
				let self_ref: &[u8] = &self.0;
				let other_ref: &[u8] = &other.0;
				self_ref.partial_cmp(other_ref)
			}
		}


		impl Hash for $name {
			fn hash<H>(&self, state: &mut H) where H: Hasher {
				state.write(&self.0);
				state.finish();
			}
		}

		impl Eq for $name { }

		impl $name {
			pub fn take(self) -> [u8; $size] {
				self.0
			}

			pub fn reversed(&self) -> Self {
				let mut result = self.clone();
				result.reverse();
				result
			}

			pub fn size() -> usize {
				$size
			}

			pub fn is_zero(&self) -> bool {
				self.0.iter().all(|b| *b == 0)
			}
		}
	}
}

impl_hash!(H32, 4);
impl_hash!(H48, 6);
impl_hash!(H96, 12);
impl_hash!(H160, 20);
impl_hash!(H256, 32);
impl_hash!(H264, 33);
impl_hash!(H512, 64);
impl_hash!(H520, 65);

known_heap_size!(0, H32, H48, H96, H160, H256, H264, H512, H520);

impl H256 {
	#[inline]
	pub fn from_reversed_str(s: &'static str) -> Self {
		H256::from(s).reversed()
	}

	#[inline]
	pub fn to_reversed_str(&self) -> String {
		self.reversed().to_string()
	}
}