libgo/go/hash/crc32/crc32_test.go

   1 // Copyright 2009 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 package crc32
   6
   7 import (
   8         "io"
   9         "testing"
  10 )
  11
  12 type test struct {
  13         ieee, castagnoli uint32
  14         in               string
  15 }
  16
  17 var golden = []test{
  18         {0x0, 0x0, ""},
  19         {0xe8b7be43, 0xc1d04330, "a"},
  20         {0x9e83486d, 0xe2a22936, "ab"},
  21         {0x352441c2, 0x364b3fb7, "abc"},
  22         {0xed82cd11, 0x92c80a31, "abcd"},
  23         {0x8587d865, 0xc450d697, "abcde"},
  24         {0x4b8e39ef, 0x53bceff1, "abcdef"},
  25         {0x312a6aa6, 0xe627f441, "abcdefg"},
  26         {0xaeef2a50, 0xa9421b7, "abcdefgh"},
  27         {0x8da988af, 0x2ddc99fc, "abcdefghi"},
  28         {0x3981703a, 0xe6599437, "abcdefghij"},
  29         {0x6b9cdfe7, 0xb2cc01fe, "Discard medicine more than two years old."},
  30         {0xc90ef73f, 0xe28207f, "He who has a shady past knows that nice guys finish last."},
  31         {0xb902341f, 0xbe93f964, "I wouldn't marry him with a ten foot pole."},
  32         {0x42080e8, 0x9e3be0c3, "Free! Free!/A trip/to Mars/for 900/empty jars/Burma Shave"},
  33         {0x154c6d11, 0xf505ef04, "The days of the digital watch are numbered.  -Tom Stoppard"},
  34         {0x4c418325, 0x85d3dc82, "Nepal premier won't resign."},
  35         {0x33955150, 0xc5142380, "For every action there is an equal and opposite government program."},
  36         {0x26216a4b, 0x75eb77dd, "His money is twice tainted: 'taint yours and 'taint mine."},
  37         {0x1abbe45e, 0x91ebe9f7, "There is no reason for any individual to have a computer in their home. -Ken Olsen, 1977"},
  38         {0xc89a94f7, 0xf0b1168e, "It's a tiny change to the code and not completely disgusting. - Bob Manchek"},
  39         {0xab3abe14, 0x572b74e2, "size:  a.out:  bad magic"},
  40         {0xbab102b6, 0x8a58a6d5, "The major problem is with sendmail.  -Mark Horton"},
  41         {0x999149d7, 0x9c426c50, "Give me a rock, paper and scissors and I will move the world.  CCFestoon"},
  42         {0x6d52a33c, 0x735400a4, "If the enemy is within range, then so are you."},
  43         {0x90631e8d, 0xbec49c95, "It's well we cannot hear the screams/That we create in others' dreams."},
  44         {0x78309130, 0xa95a2079, "You remind me of a TV show, but that's all right: I watch it anyway."},
  45         {0x7d0a377f, 0xde2e65c5, "C is as portable as Stonehedge!!"},
  46         {0x8c79fd79, 0x297a88ed, "Even if I could be Shakespeare, I think I should still choose to be Faraday. - A. Huxley"},
  47         {0xa20b7167, 0x66ed1d8b, "The fugacity of a constituent in a mixture of gases at a given temperature is proportional to its mole fraction.  Lewis-Randall Rule"},
  48         {0x8e0bb443, 0xdcded527, "How can you write a big system without C++?  -Paul Glick"},
  49 }
  50
  51 func TestGolden(t *testing.T) {
  52         castagnoliTab := MakeTable(Castagnoli)
  53
  54         for _, g := range golden {
  55                 ieee := NewIEEE()
  56                 io.WriteString(ieee, g.in)
  57                 s := ieee.Sum32()
  58                 if s != g.ieee {
  59                         t.Errorf("IEEE(%s) = 0x%x want 0x%x", g.in, s, g.ieee)
  60                 }
  61
  62                 castagnoli := New(castagnoliTab)
  63                 io.WriteString(castagnoli, g.in)
  64                 s = castagnoli.Sum32()
  65                 if s != g.castagnoli {
  66                         t.Errorf("Castagnoli(%s) = 0x%x want 0x%x", g.in, s, g.castagnoli)
  67                 }
  68
  69                 if len(g.in) > 0 {
  70                         // The SSE4.2 implementation of this has code to deal
  71                         // with misaligned data so we ensure that we test that
  72                         // too.
  73                         castagnoli = New(castagnoliTab)
  74                         io.WriteString(castagnoli, g.in[:1])
  75                         io.WriteString(castagnoli, g.in[1:])
  76                         s = castagnoli.Sum32()
  77                         if s != g.castagnoli {
  78                                 t.Errorf("Castagnoli[misaligned](%s) = 0x%x want 0x%x", g.in, s, g.castagnoli)
  79                         }
  80                 }
  81         }
  82 }
  83
  84 func BenchmarkCrc32KB(b *testing.B) {
  85         b.SetBytes(1024)
  86         data := make([]byte, 1024)
  87         for i := range data {
  88                 data[i] = byte(i)
  89         }
  90         h := NewIEEE()
  91         in := make([]byte, 0, h.Size())
  92
  93         b.ResetTimer()
  94         for i := 0; i < b.N; i++ {
  95                 h.Reset()
  96                 h.Write(data)
  97                 h.Sum(in)
  98         }
  99 }