| ... | @@ -9,17 +9,18 @@ const std = @import("../std.zig"); | ... | @@ -9,17 +9,18 @@ const std = @import("../std.zig"); |
| 9 | const debug = std.debug; | 9 | const debug = std.debug; |
| 10 | const testing = std.testing; | 10 | const testing = std.testing; |
| 11 | | 11 | |
| 12 | pub const Polynomial = struct { | 12 | pub const Polynomial = enum(u32) { |
| 13 | pub const IEEE = 0xedb88320; | 13 | IEEE = 0xedb88320, |
| 14 | pub const Castagnoli = 0x82f63b78; | 14 | Castagnoli = 0x82f63b78, |
| 15 | pub const Koopman = 0xeb31d82e; | 15 | Koopman = 0xeb31d82e, |
| | 16 | _, |
| 16 | }; | 17 | }; |
| 17 | | 18 | |
| 18 | // IEEE is by far the most common CRC and so is aliased by default. | 19 | // IEEE is by far the most common CRC and so is aliased by default. |
| 19 | pub const Crc32 = Crc32WithPoly(Polynomial.IEEE); | 20 | pub const Crc32 = Crc32WithPoly(.IEEE); |
| 20 | | 21 | |
| 21 | // slicing-by-8 crc32 implementation. | 22 | // slicing-by-8 crc32 implementation. |
| 22 | pub fn Crc32WithPoly(comptime poly: u32) type { | 23 | pub fn Crc32WithPoly(comptime poly: Polynomial) type { |
| 23 | return struct { | 24 | return struct { |
| 24 | const Self = @This(); | 25 | const Self = @This(); |
| 25 | const lookup_tables = comptime block: { | 26 | const lookup_tables = comptime block: { |
| ... | @@ -31,7 +32,7 @@ pub fn Crc32WithPoly(comptime poly: u32) type { | ... | @@ -31,7 +32,7 @@ pub fn Crc32WithPoly(comptime poly: u32) type { |
| 31 | var j: usize = 0; | 32 | var j: usize = 0; |
| 32 | while (j < 8) : (j += 1) { | 33 | while (j < 8) : (j += 1) { |
| 33 | if (crc & 1 == 1) { | 34 | if (crc & 1 == 1) { |
| 34 | crc = (crc >> 1) ^ poly; | 35 | crc = (crc >> 1) ^ @enumToInt(poly); |
| 35 | } else { | 36 | } else { |
| 36 | crc = (crc >> 1); | 37 | crc = (crc >> 1); |
| 37 | } | 38 | } |
| ... | @@ -100,7 +101,7 @@ pub fn Crc32WithPoly(comptime poly: u32) type { | ... | @@ -100,7 +101,7 @@ pub fn Crc32WithPoly(comptime poly: u32) type { |
| 100 | } | 101 | } |
| 101 | | 102 | |
| 102 | test "crc32 ieee" { | 103 | test "crc32 ieee" { |
| 103 | const Crc32Ieee = Crc32WithPoly(Polynomial.IEEE); | 104 | const Crc32Ieee = Crc32WithPoly(.IEEE); |
| 104 | | 105 | |
| 105 | testing.expect(Crc32Ieee.hash("") == 0x00000000); | 106 | testing.expect(Crc32Ieee.hash("") == 0x00000000); |
| 106 | testing.expect(Crc32Ieee.hash("a") == 0xe8b7be43); | 107 | testing.expect(Crc32Ieee.hash("a") == 0xe8b7be43); |
| ... | @@ -108,7 +109,7 @@ test "crc32 ieee" { | ... | @@ -108,7 +109,7 @@ test "crc32 ieee" { |
| 108 | } | 109 | } |
| 109 | | 110 | |
| 110 | test "crc32 castagnoli" { | 111 | test "crc32 castagnoli" { |
| 111 | const Crc32Castagnoli = Crc32WithPoly(Polynomial.Castagnoli); | 112 | const Crc32Castagnoli = Crc32WithPoly(.Castagnoli); |
| 112 | | 113 | |
| 113 | testing.expect(Crc32Castagnoli.hash("") == 0x00000000); | 114 | testing.expect(Crc32Castagnoli.hash("") == 0x00000000); |
| 114 | testing.expect(Crc32Castagnoli.hash("a") == 0xc1d04330); | 115 | testing.expect(Crc32Castagnoli.hash("a") == 0xc1d04330); |
| ... | @@ -116,7 +117,7 @@ test "crc32 castagnoli" { | ... | @@ -116,7 +117,7 @@ test "crc32 castagnoli" { |
| 116 | } | 117 | } |
| 117 | | 118 | |
| 118 | // half-byte lookup table implementation. | 119 | // half-byte lookup table implementation. |
| 119 | pub fn Crc32SmallWithPoly(comptime poly: u32) type { | 120 | pub fn Crc32SmallWithPoly(comptime poly: Polynomial) type { |
| 120 | return struct { | 121 | return struct { |
| 121 | const Self = @This(); | 122 | const Self = @This(); |
| 122 | const lookup_table = comptime block: { | 123 | const lookup_table = comptime block: { |
| ... | @@ -127,7 +128,7 @@ pub fn Crc32SmallWithPoly(comptime poly: u32) type { | ... | @@ -127,7 +128,7 @@ pub fn Crc32SmallWithPoly(comptime poly: u32) type { |
| 127 | var j: usize = 0; | 128 | var j: usize = 0; |
| 128 | while (j < 8) : (j += 1) { | 129 | while (j < 8) : (j += 1) { |
| 129 | if (crc & 1 == 1) { | 130 | if (crc & 1 == 1) { |
| 130 | crc = (crc >> 1) ^ poly; | 131 | crc = (crc >> 1) ^ @enumToInt(poly); |
| 131 | } else { | 132 | } else { |
| 132 | crc = (crc >> 1); | 133 | crc = (crc >> 1); |
| 133 | } | 134 | } |
| ... | @@ -164,7 +165,7 @@ pub fn Crc32SmallWithPoly(comptime poly: u32) type { | ... | @@ -164,7 +165,7 @@ pub fn Crc32SmallWithPoly(comptime poly: u32) type { |
| 164 | } | 165 | } |
| 165 | | 166 | |
| 166 | test "small crc32 ieee" { | 167 | test "small crc32 ieee" { |
| 167 | const Crc32Ieee = Crc32SmallWithPoly(Polynomial.IEEE); | 168 | const Crc32Ieee = Crc32SmallWithPoly(.IEEE); |
| 168 | | 169 | |
| 169 | testing.expect(Crc32Ieee.hash("") == 0x00000000); | 170 | testing.expect(Crc32Ieee.hash("") == 0x00000000); |
| 170 | testing.expect(Crc32Ieee.hash("a") == 0xe8b7be43); | 171 | testing.expect(Crc32Ieee.hash("a") == 0xe8b7be43); |
| ... | @@ -172,7 +173,7 @@ test "small crc32 ieee" { | ... | @@ -172,7 +173,7 @@ test "small crc32 ieee" { |
| 172 | } | 173 | } |
| 173 | | 174 | |
| 174 | test "small crc32 castagnoli" { | 175 | test "small crc32 castagnoli" { |
| 175 | const Crc32Castagnoli = Crc32SmallWithPoly(Polynomial.Castagnoli); | 176 | const Crc32Castagnoli = Crc32SmallWithPoly(.Castagnoli); |
| 176 | | 177 | |
| 177 | testing.expect(Crc32Castagnoli.hash("") == 0x00000000); | 178 | testing.expect(Crc32Castagnoli.hash("") == 0x00000000); |
| 178 | testing.expect(Crc32Castagnoli.hash("a") == 0xc1d04330); | 179 | testing.expect(Crc32Castagnoli.hash("a") == 0xc1d04330); |