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
178
179
180
181
182
183
184
185
186
187
188
//! `generic-array` integration with `UInt`.
// TODO(tarcieri): completely phase out `generic-array` when const generics are powerful enough

use crate::{ArrayDecoding, ArrayEncoding, ByteArray};
use generic_array::{typenum, GenericArray};

macro_rules! impl_uint_array_encoding {
    ($(($uint:ident, $bytes:path)),+) => {
        $(
            #[cfg_attr(docsrs, doc(cfg(feature = "generic-array")))]
            impl ArrayEncoding for super::$uint {
                type ByteSize = $bytes;

                #[inline]
                fn from_be_byte_array(bytes: ByteArray<Self>) -> Self {
                    Self::from_be_slice(&bytes)
                }

                #[inline]
                fn from_le_byte_array(bytes: ByteArray<Self>) -> Self {
                    Self::from_le_slice(&bytes)
                }

                #[inline]
                fn to_be_byte_array(&self) -> ByteArray<Self> {
                    let mut result = GenericArray::default();
                    self.write_be_bytes(&mut result);
                    result
                }

                #[inline]
                fn to_le_byte_array(&self) -> ByteArray<Self> {
                    let mut result = GenericArray::default();
                    self.write_le_bytes(&mut result);
                    result
                }
            }

            #[cfg_attr(docsrs, doc(cfg(feature = "generic-array")))]
            impl ArrayDecoding for GenericArray<u8, $bytes> {
                type Output = super::$uint;

                fn into_uint_be(self) -> Self::Output {
                    Self::Output::from_be_byte_array(self)
                }

                fn into_uint_le(self) -> Self::Output {
                    Self::Output::from_le_byte_array(self)
                }
            }
        )+
     };
}

// TODO(tarcieri): use `const_evaluatable_checked` when stable to make generic around bits.
impl_uint_array_encoding! {
    (U64, typenum::U8),
    (U128, typenum::U16),
    (U192, typenum::U24),
    (U256, typenum::U32),
    (U384, typenum::U48),
    (U448, typenum::U56),
    (U512, typenum::U64),
    (U768, typenum::U96),
    (U896, typenum::U112),
    (U1024, typenum::U128),
    (U1536, typenum::U192),
    (U1792, typenum::U224),
    (U2048, typenum::U256),
    (U3072, typenum::U384),
    (U3584, typenum::U448),
    (U4096, typenum::U512),
    (U6144, typenum::U768),
    (U8192, typenum::U1024)
}

#[cfg(test)]
mod tests {
    use crate::{ArrayDecoding, ArrayEncoding, Limb};
    use hex_literal::hex;

    #[cfg(target_pointer_width = "32")]
    use crate::U64 as UIntEx;

    #[cfg(target_pointer_width = "64")]
    use crate::U128 as UIntEx;

    /// Byte array that corresponds to `UIntEx`
    type ByteArray = crate::ByteArray<UIntEx>;

    #[test]
    #[cfg(target_pointer_width = "32")]
    fn from_be_byte_array() {
        let n = UIntEx::from_be_byte_array(hex!("0011223344556677").into());
        assert_eq!(n.limbs(), &[Limb(0x44556677), Limb(0x00112233)]);
    }

    #[test]
    #[cfg(target_pointer_width = "64")]
    fn from_be_byte_array() {
        let n = UIntEx::from_be_byte_array(hex!("00112233445566778899aabbccddeeff").into());
        assert_eq!(
            n.limbs(),
            &[Limb(0x8899aabbccddeeff), Limb(0x0011223344556677)]
        );
    }

    #[test]
    #[cfg(target_pointer_width = "32")]
    fn from_le_byte_array() {
        let n = UIntEx::from_le_byte_array(hex!("7766554433221100").into());
        assert_eq!(n.limbs(), &[Limb(0x44556677), Limb(0x00112233)]);
    }

    #[test]
    #[cfg(target_pointer_width = "64")]
    fn from_le_byte_array() {
        let n = UIntEx::from_le_byte_array(hex!("ffeeddccbbaa99887766554433221100").into());
        assert_eq!(
            n.limbs(),
            &[Limb(0x8899aabbccddeeff), Limb(0x0011223344556677)]
        );
    }

    #[test]
    #[cfg(target_pointer_width = "32")]
    fn to_be_byte_array() {
        let expected_bytes = ByteArray::from(hex!("0011223344556677"));
        let actual_bytes = UIntEx::from_be_byte_array(expected_bytes).to_be_byte_array();
        assert_eq!(expected_bytes, actual_bytes);
    }

    #[test]
    #[cfg(target_pointer_width = "64")]
    fn to_be_byte_array() {
        let expected_bytes = ByteArray::from(hex!("00112233445566778899aabbccddeeff"));
        let actual_bytes = UIntEx::from_be_byte_array(expected_bytes).to_be_byte_array();
        assert_eq!(expected_bytes, actual_bytes);
    }

    #[test]
    #[cfg(target_pointer_width = "32")]
    fn to_le_byte_array() {
        let expected_bytes = ByteArray::from(hex!("7766554433221100"));
        let actual_bytes = UIntEx::from_le_byte_array(expected_bytes).to_le_byte_array();
        assert_eq!(expected_bytes, actual_bytes);
    }

    #[test]
    #[cfg(target_pointer_width = "64")]
    fn to_le_byte_array() {
        let expected_bytes = ByteArray::from(hex!("ffeeddccbbaa99887766554433221100"));
        let actual_bytes = UIntEx::from_le_byte_array(expected_bytes).to_le_byte_array();
        assert_eq!(expected_bytes, actual_bytes);
    }

    #[test]
    #[cfg(target_pointer_width = "32")]
    fn into_uint_be() {
        let expected_bytes = ByteArray::from(hex!("0011223344556677"));
        let actual_bytes = expected_bytes.into_uint_be().to_be_byte_array();
        assert_eq!(expected_bytes, actual_bytes);
    }

    #[test]
    #[cfg(target_pointer_width = "64")]
    fn into_uint_be() {
        let expected_bytes = ByteArray::from(hex!("00112233445566778899aabbccddeeff"));
        let actual_bytes = expected_bytes.into_uint_be().to_be_byte_array();
        assert_eq!(expected_bytes, actual_bytes);
    }

    #[test]
    #[cfg(target_pointer_width = "32")]
    fn into_uint_le() {
        let expected_bytes = ByteArray::from(hex!("7766554433221100"));
        let actual_bytes = expected_bytes.into_uint_le().to_le_byte_array();
        assert_eq!(expected_bytes, actual_bytes);
    }

    #[test]
    #[cfg(target_pointer_width = "64")]
    fn into_uint_le() {
        let expected_bytes = ByteArray::from(hex!("ffeeddccbbaa99887766554433221100"));
        let actual_bytes = expected_bytes.into_uint_le().to_le_byte_array();
        assert_eq!(expected_bytes, actual_bytes);
    }
}