replace zxq.co/ripple/hanayo
This commit is contained in:
193
vendor/github.com/klauspost/compress/flate/asm_test.go
generated
vendored
Normal file
193
vendor/github.com/klauspost/compress/flate/asm_test.go
generated
vendored
Normal file
@@ -0,0 +1,193 @@
|
||||
// Copyright 2015, Klaus Post, see LICENSE for details.
|
||||
|
||||
//+build amd64
|
||||
|
||||
package flate
|
||||
|
||||
import (
|
||||
"math/rand"
|
||||
"testing"
|
||||
)
|
||||
|
||||
func TestCRC(t *testing.T) {
|
||||
if !useSSE42 {
|
||||
t.Skip("Skipping CRC test, no SSE 4.2 available")
|
||||
}
|
||||
for _, x := range deflateTests {
|
||||
y := x.out
|
||||
if len(y) >= minMatchLength {
|
||||
t.Logf("In: %v, Out:0x%08x", y[0:minMatchLength], crc32sse(y[0:minMatchLength]))
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestCRCBulk(t *testing.T) {
|
||||
if !useSSE42 {
|
||||
t.Skip("Skipping CRC test, no SSE 4.2 available")
|
||||
}
|
||||
for _, x := range deflateTests {
|
||||
y := x.out
|
||||
y = append(y, y...)
|
||||
y = append(y, y...)
|
||||
y = append(y, y...)
|
||||
y = append(y, y...)
|
||||
y = append(y, y...)
|
||||
y = append(y, y...)
|
||||
if !testing.Short() {
|
||||
y = append(y, y...)
|
||||
y = append(y, y...)
|
||||
}
|
||||
y = append(y, 1)
|
||||
if len(y) >= minMatchLength {
|
||||
for j := len(y) - 1; j >= 4; j-- {
|
||||
|
||||
// Create copy, so we easier detect of-of-bound reads
|
||||
test := make([]byte, j)
|
||||
test2 := make([]byte, j)
|
||||
copy(test, y[:j])
|
||||
copy(test2, y[:j])
|
||||
|
||||
// We allocate one more than we need to test for unintentional overwrites
|
||||
dst := make([]uint32, j-3+1)
|
||||
ref := make([]uint32, j-3+1)
|
||||
for i := range dst {
|
||||
dst[i] = uint32(i + 100)
|
||||
ref[i] = uint32(i + 101)
|
||||
}
|
||||
// Last entry must NOT be overwritten.
|
||||
dst[j-3] = 0x1234
|
||||
ref[j-3] = 0x1234
|
||||
|
||||
// Do two encodes we can compare
|
||||
crc32sseAll(test, dst)
|
||||
crc32sseAll(test2, ref)
|
||||
|
||||
// Check all values
|
||||
for i, got := range dst {
|
||||
if i == j-3 {
|
||||
if dst[i] != 0x1234 {
|
||||
t.Fatalf("end of expected dst overwritten, was %08x", uint32(dst[i]))
|
||||
}
|
||||
continue
|
||||
}
|
||||
expect := crc32sse(y[i : i+4])
|
||||
if got != expect && got == uint32(i)+100 {
|
||||
t.Errorf("Len:%d Index:%d, expected 0x%08x but not modified", len(y), i, uint32(expect))
|
||||
} else if got != expect {
|
||||
t.Errorf("Len:%d Index:%d, got 0x%08x expected:0x%08x", len(y), i, uint32(got), uint32(expect))
|
||||
}
|
||||
expect = ref[i]
|
||||
if got != expect {
|
||||
t.Errorf("Len:%d Index:%d, got 0x%08x expected:0x%08x", len(y), i, got, expect)
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestMatchLen(t *testing.T) {
|
||||
if !useSSE42 {
|
||||
t.Skip("Skipping Matchlen test, no SSE 4.2 available")
|
||||
}
|
||||
// Maximum length tested
|
||||
var maxLen = 512
|
||||
|
||||
// Skips per iteration
|
||||
is, js, ks := 3, 2, 1
|
||||
if testing.Short() {
|
||||
is, js, ks = 7, 5, 3
|
||||
}
|
||||
|
||||
a := make([]byte, maxLen)
|
||||
b := make([]byte, maxLen)
|
||||
bb := make([]byte, maxLen)
|
||||
rand.Seed(1)
|
||||
for i := range a {
|
||||
a[i] = byte(rand.Int63())
|
||||
b[i] = byte(rand.Int63())
|
||||
}
|
||||
|
||||
// Test different lengths
|
||||
for i := 0; i < maxLen; i += is {
|
||||
// Test different dst offsets.
|
||||
for j := 0; j < maxLen-1; j += js {
|
||||
copy(bb, b)
|
||||
// Test different src offsets
|
||||
for k := i - 1; k >= 0; k -= ks {
|
||||
copy(bb[j:], a[k:i])
|
||||
maxTest := maxLen - j
|
||||
if maxTest > maxLen-k {
|
||||
maxTest = maxLen - k
|
||||
}
|
||||
got := matchLenSSE4(a[k:], bb[j:], maxTest)
|
||||
expect := matchLenReference(a[k:], bb[j:], maxTest)
|
||||
if got > maxTest || got < 0 {
|
||||
t.Fatalf("unexpected result %d (len:%d, src offset: %d, dst offset:%d)", got, maxTest, k, j)
|
||||
}
|
||||
if got != expect {
|
||||
t.Fatalf("Mismatch, expected %d, got %d", expect, got)
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// matchLenReference is a reference matcher.
|
||||
func matchLenReference(a, b []byte, max int) int {
|
||||
for i := 0; i < max; i++ {
|
||||
if a[i] != b[i] {
|
||||
return i
|
||||
}
|
||||
}
|
||||
return max
|
||||
}
|
||||
|
||||
func TestHistogram(t *testing.T) {
|
||||
if !useSSE42 {
|
||||
t.Skip("Skipping Matchlen test, no SSE 4.2 available")
|
||||
}
|
||||
// Maximum length tested
|
||||
const maxLen = 65536
|
||||
var maxOff = 8
|
||||
|
||||
// Skips per iteration
|
||||
is, js := 5, 3
|
||||
if testing.Short() {
|
||||
is, js = 9, 1
|
||||
maxOff = 1
|
||||
}
|
||||
|
||||
a := make([]byte, maxLen+maxOff)
|
||||
rand.Seed(1)
|
||||
for i := range a {
|
||||
a[i] = byte(rand.Int63())
|
||||
}
|
||||
|
||||
// Test different lengths
|
||||
for i := 0; i <= maxLen; i += is {
|
||||
// Test different offsets
|
||||
for j := 0; j < maxOff; j += js {
|
||||
var got [256]int32
|
||||
var reference [256]int32
|
||||
|
||||
histogram(a[j:i+j], got[:])
|
||||
histogramReference(a[j:i+j], reference[:])
|
||||
for k := range got {
|
||||
if got[k] != reference[k] {
|
||||
t.Fatalf("mismatch at len:%d, offset:%d, value %d: (got) %d != %d (expected)", i, j, k, got[k], reference[k])
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// histogramReference is a reference
|
||||
func histogramReference(b []byte, h []int32) {
|
||||
if len(h) < 256 {
|
||||
panic("Histogram too small")
|
||||
}
|
||||
for _, t := range b {
|
||||
h[t]++
|
||||
}
|
||||
}
|
32
vendor/github.com/klauspost/compress/flate/copy.go
generated
vendored
Normal file
32
vendor/github.com/klauspost/compress/flate/copy.go
generated
vendored
Normal file
@@ -0,0 +1,32 @@
|
||||
// Copyright 2012 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package flate
|
||||
|
||||
// forwardCopy is like the built-in copy function except that it always goes
|
||||
// forward from the start, even if the dst and src overlap.
|
||||
// It is equivalent to:
|
||||
// for i := 0; i < n; i++ {
|
||||
// mem[dst+i] = mem[src+i]
|
||||
// }
|
||||
func forwardCopy(mem []byte, dst, src, n int) {
|
||||
if dst <= src {
|
||||
copy(mem[dst:dst+n], mem[src:src+n])
|
||||
return
|
||||
}
|
||||
for {
|
||||
if dst >= src+n {
|
||||
copy(mem[dst:dst+n], mem[src:src+n])
|
||||
return
|
||||
}
|
||||
// There is some forward overlap. The destination
|
||||
// will be filled with a repeated pattern of mem[src:src+k].
|
||||
// We copy one instance of the pattern here, then repeat.
|
||||
// Each time around this loop k will double.
|
||||
k := dst - src
|
||||
copy(mem[dst:dst+k], mem[src:src+k])
|
||||
n -= k
|
||||
dst += k
|
||||
}
|
||||
}
|
54
vendor/github.com/klauspost/compress/flate/copy_test.go
generated
vendored
Normal file
54
vendor/github.com/klauspost/compress/flate/copy_test.go
generated
vendored
Normal file
@@ -0,0 +1,54 @@
|
||||
// Copyright 2012 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package flate
|
||||
|
||||
import (
|
||||
"testing"
|
||||
)
|
||||
|
||||
func TestForwardCopy(t *testing.T) {
|
||||
testCases := []struct {
|
||||
dst0, dst1 int
|
||||
src0, src1 int
|
||||
want string
|
||||
}{
|
||||
{0, 9, 0, 9, "012345678"},
|
||||
{0, 5, 4, 9, "45678"},
|
||||
{4, 9, 0, 5, "01230"},
|
||||
{1, 6, 3, 8, "34567"},
|
||||
{3, 8, 1, 6, "12121"},
|
||||
{0, 9, 3, 6, "345"},
|
||||
{3, 6, 0, 9, "012"},
|
||||
{1, 6, 0, 9, "00000"},
|
||||
{0, 4, 7, 8, "7"},
|
||||
{0, 1, 6, 8, "6"},
|
||||
{4, 4, 6, 9, ""},
|
||||
{2, 8, 6, 6, ""},
|
||||
{0, 0, 0, 0, ""},
|
||||
}
|
||||
for _, tc := range testCases {
|
||||
b := []byte("0123456789")
|
||||
n := tc.dst1 - tc.dst0
|
||||
if tc.src1-tc.src0 < n {
|
||||
n = tc.src1 - tc.src0
|
||||
}
|
||||
forwardCopy(b, tc.dst0, tc.src0, n)
|
||||
got := string(b[tc.dst0 : tc.dst0+n])
|
||||
if got != tc.want {
|
||||
t.Errorf("dst=b[%d:%d], src=b[%d:%d]: got %q, want %q",
|
||||
tc.dst0, tc.dst1, tc.src0, tc.src1, got, tc.want)
|
||||
}
|
||||
// Check that the bytes outside of dst[:n] were not modified.
|
||||
for i, x := range b {
|
||||
if i >= tc.dst0 && i < tc.dst0+n {
|
||||
continue
|
||||
}
|
||||
if int(x) != '0'+i {
|
||||
t.Errorf("dst=b[%d:%d], src=b[%d:%d]: copy overrun at b[%d]: got '%c', want '%c'",
|
||||
tc.dst0, tc.dst1, tc.src0, tc.src1, i, x, '0'+i)
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
41
vendor/github.com/klauspost/compress/flate/crc32_amd64.go
generated
vendored
Normal file
41
vendor/github.com/klauspost/compress/flate/crc32_amd64.go
generated
vendored
Normal file
@@ -0,0 +1,41 @@
|
||||
//+build !noasm
|
||||
//+build !appengine
|
||||
|
||||
// Copyright 2015, Klaus Post, see LICENSE for details.
|
||||
|
||||
package flate
|
||||
|
||||
import (
|
||||
"github.com/klauspost/cpuid"
|
||||
)
|
||||
|
||||
// crc32sse returns a hash for the first 4 bytes of the slice
|
||||
// len(a) must be >= 4.
|
||||
//go:noescape
|
||||
func crc32sse(a []byte) uint32
|
||||
|
||||
// crc32sseAll calculates hashes for each 4-byte set in a.
|
||||
// dst must be east len(a) - 4 in size.
|
||||
// The size is not checked by the assembly.
|
||||
//go:noescape
|
||||
func crc32sseAll(a []byte, dst []uint32)
|
||||
|
||||
// matchLenSSE4 returns the number of matching bytes in a and b
|
||||
// up to length 'max'. Both slices must be at least 'max'
|
||||
// bytes in size.
|
||||
//
|
||||
// TODO: drop the "SSE4" name, since it doesn't use any SSE instructions.
|
||||
//
|
||||
//go:noescape
|
||||
func matchLenSSE4(a, b []byte, max int) int
|
||||
|
||||
// histogram accumulates a histogram of b in h.
|
||||
// h must be at least 256 entries in length,
|
||||
// and must be cleared before calling this function.
|
||||
//go:noescape
|
||||
func histogram(b []byte, h []int32)
|
||||
|
||||
// Detect SSE 4.2 feature.
|
||||
func init() {
|
||||
useSSE42 = cpuid.CPU.SSE42()
|
||||
}
|
213
vendor/github.com/klauspost/compress/flate/crc32_amd64.s
generated
vendored
Normal file
213
vendor/github.com/klauspost/compress/flate/crc32_amd64.s
generated
vendored
Normal file
@@ -0,0 +1,213 @@
|
||||
//+build !noasm
|
||||
//+build !appengine
|
||||
|
||||
// Copyright 2015, Klaus Post, see LICENSE for details.
|
||||
|
||||
// func crc32sse(a []byte) uint32
|
||||
TEXT ·crc32sse(SB), 4, $0
|
||||
MOVQ a+0(FP), R10
|
||||
XORQ BX, BX
|
||||
|
||||
// CRC32 dword (R10), EBX
|
||||
BYTE $0xF2; BYTE $0x41; BYTE $0x0f
|
||||
BYTE $0x38; BYTE $0xf1; BYTE $0x1a
|
||||
|
||||
MOVL BX, ret+24(FP)
|
||||
RET
|
||||
|
||||
// func crc32sseAll(a []byte, dst []uint32)
|
||||
TEXT ·crc32sseAll(SB), 4, $0
|
||||
MOVQ a+0(FP), R8 // R8: src
|
||||
MOVQ a_len+8(FP), R10 // input length
|
||||
MOVQ dst+24(FP), R9 // R9: dst
|
||||
SUBQ $4, R10
|
||||
JS end
|
||||
JZ one_crc
|
||||
MOVQ R10, R13
|
||||
SHRQ $2, R10 // len/4
|
||||
ANDQ $3, R13 // len&3
|
||||
XORQ BX, BX
|
||||
ADDQ $1, R13
|
||||
TESTQ R10, R10
|
||||
JZ rem_loop
|
||||
|
||||
crc_loop:
|
||||
MOVQ (R8), R11
|
||||
XORQ BX, BX
|
||||
XORQ DX, DX
|
||||
XORQ DI, DI
|
||||
MOVQ R11, R12
|
||||
SHRQ $8, R11
|
||||
MOVQ R12, AX
|
||||
MOVQ R11, CX
|
||||
SHRQ $16, R12
|
||||
SHRQ $16, R11
|
||||
MOVQ R12, SI
|
||||
|
||||
// CRC32 EAX, EBX
|
||||
BYTE $0xF2; BYTE $0x0f
|
||||
BYTE $0x38; BYTE $0xf1; BYTE $0xd8
|
||||
|
||||
// CRC32 ECX, EDX
|
||||
BYTE $0xF2; BYTE $0x0f
|
||||
BYTE $0x38; BYTE $0xf1; BYTE $0xd1
|
||||
|
||||
// CRC32 ESI, EDI
|
||||
BYTE $0xF2; BYTE $0x0f
|
||||
BYTE $0x38; BYTE $0xf1; BYTE $0xfe
|
||||
MOVL BX, (R9)
|
||||
MOVL DX, 4(R9)
|
||||
MOVL DI, 8(R9)
|
||||
|
||||
XORQ BX, BX
|
||||
MOVL R11, AX
|
||||
|
||||
// CRC32 EAX, EBX
|
||||
BYTE $0xF2; BYTE $0x0f
|
||||
BYTE $0x38; BYTE $0xf1; BYTE $0xd8
|
||||
MOVL BX, 12(R9)
|
||||
|
||||
ADDQ $16, R9
|
||||
ADDQ $4, R8
|
||||
XORQ BX, BX
|
||||
SUBQ $1, R10
|
||||
JNZ crc_loop
|
||||
|
||||
rem_loop:
|
||||
MOVL (R8), AX
|
||||
|
||||
// CRC32 EAX, EBX
|
||||
BYTE $0xF2; BYTE $0x0f
|
||||
BYTE $0x38; BYTE $0xf1; BYTE $0xd8
|
||||
|
||||
MOVL BX, (R9)
|
||||
ADDQ $4, R9
|
||||
ADDQ $1, R8
|
||||
XORQ BX, BX
|
||||
SUBQ $1, R13
|
||||
JNZ rem_loop
|
||||
|
||||
end:
|
||||
RET
|
||||
|
||||
one_crc:
|
||||
MOVQ $1, R13
|
||||
XORQ BX, BX
|
||||
JMP rem_loop
|
||||
|
||||
// func matchLenSSE4(a, b []byte, max int) int
|
||||
TEXT ·matchLenSSE4(SB), 4, $0
|
||||
MOVQ a_base+0(FP), SI
|
||||
MOVQ b_base+24(FP), DI
|
||||
MOVQ DI, DX
|
||||
MOVQ max+48(FP), CX
|
||||
|
||||
cmp8:
|
||||
// As long as we are 8 or more bytes before the end of max, we can load and
|
||||
// compare 8 bytes at a time. If those 8 bytes are equal, repeat.
|
||||
CMPQ CX, $8
|
||||
JLT cmp1
|
||||
MOVQ (SI), AX
|
||||
MOVQ (DI), BX
|
||||
CMPQ AX, BX
|
||||
JNE bsf
|
||||
ADDQ $8, SI
|
||||
ADDQ $8, DI
|
||||
SUBQ $8, CX
|
||||
JMP cmp8
|
||||
|
||||
bsf:
|
||||
// If those 8 bytes were not equal, XOR the two 8 byte values, and return
|
||||
// the index of the first byte that differs. The BSF instruction finds the
|
||||
// least significant 1 bit, the amd64 architecture is little-endian, and
|
||||
// the shift by 3 converts a bit index to a byte index.
|
||||
XORQ AX, BX
|
||||
BSFQ BX, BX
|
||||
SHRQ $3, BX
|
||||
ADDQ BX, DI
|
||||
|
||||
// Subtract off &b[0] to convert from &b[ret] to ret, and return.
|
||||
SUBQ DX, DI
|
||||
MOVQ DI, ret+56(FP)
|
||||
RET
|
||||
|
||||
cmp1:
|
||||
// In the slices' tail, compare 1 byte at a time.
|
||||
CMPQ CX, $0
|
||||
JEQ matchLenEnd
|
||||
MOVB (SI), AX
|
||||
MOVB (DI), BX
|
||||
CMPB AX, BX
|
||||
JNE matchLenEnd
|
||||
ADDQ $1, SI
|
||||
ADDQ $1, DI
|
||||
SUBQ $1, CX
|
||||
JMP cmp1
|
||||
|
||||
matchLenEnd:
|
||||
// Subtract off &b[0] to convert from &b[ret] to ret, and return.
|
||||
SUBQ DX, DI
|
||||
MOVQ DI, ret+56(FP)
|
||||
RET
|
||||
|
||||
// func histogram(b []byte, h []int32)
|
||||
TEXT ·histogram(SB), 4, $0
|
||||
MOVQ b+0(FP), SI // SI: &b
|
||||
MOVQ b_len+8(FP), R9 // R9: len(b)
|
||||
MOVQ h+24(FP), DI // DI: Histogram
|
||||
MOVQ R9, R8
|
||||
SHRQ $3, R8
|
||||
JZ hist1
|
||||
XORQ R11, R11
|
||||
|
||||
loop_hist8:
|
||||
MOVQ (SI), R10
|
||||
|
||||
MOVB R10, R11
|
||||
INCL (DI)(R11*4)
|
||||
SHRQ $8, R10
|
||||
|
||||
MOVB R10, R11
|
||||
INCL (DI)(R11*4)
|
||||
SHRQ $8, R10
|
||||
|
||||
MOVB R10, R11
|
||||
INCL (DI)(R11*4)
|
||||
SHRQ $8, R10
|
||||
|
||||
MOVB R10, R11
|
||||
INCL (DI)(R11*4)
|
||||
SHRQ $8, R10
|
||||
|
||||
MOVB R10, R11
|
||||
INCL (DI)(R11*4)
|
||||
SHRQ $8, R10
|
||||
|
||||
MOVB R10, R11
|
||||
INCL (DI)(R11*4)
|
||||
SHRQ $8, R10
|
||||
|
||||
MOVB R10, R11
|
||||
INCL (DI)(R11*4)
|
||||
SHRQ $8, R10
|
||||
|
||||
INCL (DI)(R10*4)
|
||||
|
||||
ADDQ $8, SI
|
||||
DECQ R8
|
||||
JNZ loop_hist8
|
||||
|
||||
hist1:
|
||||
ANDQ $7, R9
|
||||
JZ end_hist
|
||||
XORQ R10, R10
|
||||
|
||||
loop_hist1:
|
||||
MOVB (SI), R10
|
||||
INCL (DI)(R10*4)
|
||||
INCQ SI
|
||||
DECQ R9
|
||||
JNZ loop_hist1
|
||||
|
||||
end_hist:
|
||||
RET
|
35
vendor/github.com/klauspost/compress/flate/crc32_noasm.go
generated
vendored
Normal file
35
vendor/github.com/klauspost/compress/flate/crc32_noasm.go
generated
vendored
Normal file
@@ -0,0 +1,35 @@
|
||||
//+build !amd64 noasm appengine
|
||||
|
||||
// Copyright 2015, Klaus Post, see LICENSE for details.
|
||||
|
||||
package flate
|
||||
|
||||
func init() {
|
||||
useSSE42 = false
|
||||
}
|
||||
|
||||
// crc32sse should never be called.
|
||||
func crc32sse(a []byte) uint32 {
|
||||
panic("no assembler")
|
||||
}
|
||||
|
||||
// crc32sseAll should never be called.
|
||||
func crc32sseAll(a []byte, dst []uint32) {
|
||||
panic("no assembler")
|
||||
}
|
||||
|
||||
// matchLenSSE4 should never be called.
|
||||
func matchLenSSE4(a, b []byte, max int) int {
|
||||
panic("no assembler")
|
||||
return 0
|
||||
}
|
||||
|
||||
// histogram accumulates a histogram of b in h.
|
||||
//
|
||||
// len(h) must be >= 256, and h's elements must be all zeroes.
|
||||
func histogram(b []byte, h []int32) {
|
||||
h = h[:256]
|
||||
for _, t := range b {
|
||||
h[t]++
|
||||
}
|
||||
}
|
1353
vendor/github.com/klauspost/compress/flate/deflate.go
generated
vendored
Normal file
1353
vendor/github.com/klauspost/compress/flate/deflate.go
generated
vendored
Normal file
File diff suppressed because it is too large
Load Diff
648
vendor/github.com/klauspost/compress/flate/deflate_test.go
generated
vendored
Normal file
648
vendor/github.com/klauspost/compress/flate/deflate_test.go
generated
vendored
Normal file
@@ -0,0 +1,648 @@
|
||||
// Copyright 2009 The Go Authors. All rights reserved.
|
||||
// Copyright (c) 2015 Klaus Post
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package flate
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"fmt"
|
||||
"io"
|
||||
"io/ioutil"
|
||||
"reflect"
|
||||
"strings"
|
||||
"sync"
|
||||
"testing"
|
||||
)
|
||||
|
||||
type deflateTest struct {
|
||||
in []byte
|
||||
level int
|
||||
out []byte
|
||||
}
|
||||
|
||||
type deflateInflateTest struct {
|
||||
in []byte
|
||||
}
|
||||
|
||||
type reverseBitsTest struct {
|
||||
in uint16
|
||||
bitCount uint8
|
||||
out uint16
|
||||
}
|
||||
|
||||
var deflateTests = []*deflateTest{
|
||||
{[]byte{}, 0, []byte{1, 0, 0, 255, 255}},
|
||||
{[]byte{0x11}, BestCompression, []byte{18, 4, 4, 0, 0, 255, 255}},
|
||||
{[]byte{0x11}, BestCompression, []byte{18, 4, 4, 0, 0, 255, 255}},
|
||||
{[]byte{0x11}, BestCompression, []byte{18, 4, 4, 0, 0, 255, 255}},
|
||||
|
||||
{[]byte{0x11}, 0, []byte{0, 1, 0, 254, 255, 17, 1, 0, 0, 255, 255}},
|
||||
{[]byte{0x11, 0x12}, 0, []byte{0, 2, 0, 253, 255, 17, 18, 1, 0, 0, 255, 255}},
|
||||
{[]byte{0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11}, 0,
|
||||
[]byte{0, 8, 0, 247, 255, 17, 17, 17, 17, 17, 17, 17, 17, 1, 0, 0, 255, 255},
|
||||
},
|
||||
{[]byte{}, 1, []byte{1, 0, 0, 255, 255}},
|
||||
{[]byte{0x11}, BestCompression, []byte{18, 4, 4, 0, 0, 255, 255}},
|
||||
{[]byte{0x11, 0x12}, BestCompression, []byte{18, 20, 2, 4, 0, 0, 255, 255}},
|
||||
{[]byte{0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11}, BestCompression, []byte{18, 132, 2, 64, 0, 0, 0, 255, 255}},
|
||||
{[]byte{}, 9, []byte{1, 0, 0, 255, 255}},
|
||||
{[]byte{0x11}, 9, []byte{18, 4, 4, 0, 0, 255, 255}},
|
||||
{[]byte{0x11, 0x12}, 9, []byte{18, 20, 2, 4, 0, 0, 255, 255}},
|
||||
{[]byte{0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11}, 9, []byte{18, 132, 2, 64, 0, 0, 0, 255, 255}},
|
||||
}
|
||||
|
||||
var deflateInflateTests = []*deflateInflateTest{
|
||||
{[]byte{}},
|
||||
{[]byte{0x11}},
|
||||
{[]byte{0x11, 0x12}},
|
||||
{[]byte{0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11}},
|
||||
{[]byte{0x11, 0x10, 0x13, 0x41, 0x21, 0x21, 0x41, 0x13, 0x87, 0x78, 0x13}},
|
||||
{largeDataChunk()},
|
||||
}
|
||||
|
||||
var reverseBitsTests = []*reverseBitsTest{
|
||||
{1, 1, 1},
|
||||
{1, 2, 2},
|
||||
{1, 3, 4},
|
||||
{1, 4, 8},
|
||||
{1, 5, 16},
|
||||
{17, 5, 17},
|
||||
{257, 9, 257},
|
||||
{29, 5, 23},
|
||||
}
|
||||
|
||||
func largeDataChunk() []byte {
|
||||
result := make([]byte, 100000)
|
||||
for i := range result {
|
||||
result[i] = byte(i * i & 0xFF)
|
||||
}
|
||||
return result
|
||||
}
|
||||
|
||||
func TestCRCBulkOld(t *testing.T) {
|
||||
for _, x := range deflateTests {
|
||||
y := x.out
|
||||
if len(y) >= minMatchLength {
|
||||
y = append(y, y...)
|
||||
for j := 4; j < len(y); j++ {
|
||||
y := y[:j]
|
||||
dst := make([]uint32, len(y)-minMatchLength+1)
|
||||
for i := range dst {
|
||||
dst[i] = uint32(i + 100)
|
||||
}
|
||||
bulkHash4(y, dst)
|
||||
for i, val := range dst {
|
||||
got := val
|
||||
expect := hash4(y[i:])
|
||||
if got != expect && got == uint32(i)+100 {
|
||||
t.Errorf("Len:%d Index:%d, expected 0x%08x but not modified", len(y), i, expect)
|
||||
} else if got != expect {
|
||||
t.Errorf("Len:%d Index:%d, got 0x%08x expected:0x%08x", len(y), i, got, expect)
|
||||
} else {
|
||||
//t.Logf("Len:%d Index:%d OK (0x%08x)", len(y), i, got)
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestDeflate(t *testing.T) {
|
||||
for _, h := range deflateTests {
|
||||
var buf bytes.Buffer
|
||||
w, err := NewWriter(&buf, h.level)
|
||||
if err != nil {
|
||||
t.Errorf("NewWriter: %v", err)
|
||||
continue
|
||||
}
|
||||
w.Write(h.in)
|
||||
w.Close()
|
||||
if !bytes.Equal(buf.Bytes(), h.out) {
|
||||
t.Errorf("Deflate(%d, %x) = \n%#v, want \n%#v", h.level, h.in, buf.Bytes(), h.out)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// A sparseReader returns a stream consisting of 0s followed by 1<<16 1s.
|
||||
// This tests missing hash references in a very large input.
|
||||
type sparseReader struct {
|
||||
l int64
|
||||
cur int64
|
||||
}
|
||||
|
||||
func (r *sparseReader) Read(b []byte) (n int, err error) {
|
||||
if r.cur >= r.l {
|
||||
return 0, io.EOF
|
||||
}
|
||||
n = len(b)
|
||||
cur := r.cur + int64(n)
|
||||
if cur > r.l {
|
||||
n -= int(cur - r.l)
|
||||
cur = r.l
|
||||
}
|
||||
for i := range b[0:n] {
|
||||
if r.cur+int64(i) >= r.l-1<<16 {
|
||||
b[i] = 1
|
||||
} else {
|
||||
b[i] = 0
|
||||
}
|
||||
}
|
||||
r.cur = cur
|
||||
return
|
||||
}
|
||||
|
||||
func TestVeryLongSparseChunk(t *testing.T) {
|
||||
if testing.Short() {
|
||||
t.Skip("skipping sparse chunk during short test")
|
||||
}
|
||||
w, err := NewWriter(ioutil.Discard, 1)
|
||||
if err != nil {
|
||||
t.Errorf("NewWriter: %v", err)
|
||||
return
|
||||
}
|
||||
if _, err = io.Copy(w, &sparseReader{l: 23E8}); err != nil {
|
||||
t.Errorf("Compress failed: %v", err)
|
||||
return
|
||||
}
|
||||
}
|
||||
|
||||
type syncBuffer struct {
|
||||
buf bytes.Buffer
|
||||
mu sync.RWMutex
|
||||
closed bool
|
||||
ready chan bool
|
||||
}
|
||||
|
||||
func newSyncBuffer() *syncBuffer {
|
||||
return &syncBuffer{ready: make(chan bool, 1)}
|
||||
}
|
||||
|
||||
func (b *syncBuffer) Read(p []byte) (n int, err error) {
|
||||
for {
|
||||
b.mu.RLock()
|
||||
n, err = b.buf.Read(p)
|
||||
b.mu.RUnlock()
|
||||
if n > 0 || b.closed {
|
||||
return
|
||||
}
|
||||
<-b.ready
|
||||
}
|
||||
}
|
||||
|
||||
func (b *syncBuffer) signal() {
|
||||
select {
|
||||
case b.ready <- true:
|
||||
default:
|
||||
}
|
||||
}
|
||||
|
||||
func (b *syncBuffer) Write(p []byte) (n int, err error) {
|
||||
n, err = b.buf.Write(p)
|
||||
b.signal()
|
||||
return
|
||||
}
|
||||
|
||||
func (b *syncBuffer) WriteMode() {
|
||||
b.mu.Lock()
|
||||
}
|
||||
|
||||
func (b *syncBuffer) ReadMode() {
|
||||
b.mu.Unlock()
|
||||
b.signal()
|
||||
}
|
||||
|
||||
func (b *syncBuffer) Close() error {
|
||||
b.closed = true
|
||||
b.signal()
|
||||
return nil
|
||||
}
|
||||
|
||||
func testSync(t *testing.T, level int, input []byte, name string) {
|
||||
if len(input) == 0 {
|
||||
return
|
||||
}
|
||||
|
||||
t.Logf("--testSync %d, %d, %s", level, len(input), name)
|
||||
buf := newSyncBuffer()
|
||||
buf1 := new(bytes.Buffer)
|
||||
buf.WriteMode()
|
||||
w, err := NewWriter(io.MultiWriter(buf, buf1), level)
|
||||
if err != nil {
|
||||
t.Errorf("NewWriter: %v", err)
|
||||
return
|
||||
}
|
||||
r := NewReader(buf)
|
||||
|
||||
// Write half the input and read back.
|
||||
for i := 0; i < 2; i++ {
|
||||
var lo, hi int
|
||||
if i == 0 {
|
||||
lo, hi = 0, (len(input)+1)/2
|
||||
} else {
|
||||
lo, hi = (len(input)+1)/2, len(input)
|
||||
}
|
||||
t.Logf("#%d: write %d-%d", i, lo, hi)
|
||||
if _, err := w.Write(input[lo:hi]); err != nil {
|
||||
t.Errorf("testSync: write: %v", err)
|
||||
return
|
||||
}
|
||||
if i == 0 {
|
||||
if err := w.Flush(); err != nil {
|
||||
t.Errorf("testSync: flush: %v", err)
|
||||
return
|
||||
}
|
||||
} else {
|
||||
if err := w.Close(); err != nil {
|
||||
t.Errorf("testSync: close: %v", err)
|
||||
}
|
||||
}
|
||||
buf.ReadMode()
|
||||
out := make([]byte, hi-lo+1)
|
||||
m, err := io.ReadAtLeast(r, out, hi-lo)
|
||||
t.Logf("#%d: read %d", i, m)
|
||||
if m != hi-lo || err != nil {
|
||||
t.Errorf("testSync/%d (%d, %d, %s): read %d: %d, %v (%d left)", i, level, len(input), name, hi-lo, m, err, buf.buf.Len())
|
||||
return
|
||||
}
|
||||
if !bytes.Equal(input[lo:hi], out[:hi-lo]) {
|
||||
t.Errorf("testSync/%d: read wrong bytes: %x vs %x", i, input[lo:hi], out[:hi-lo])
|
||||
return
|
||||
}
|
||||
// This test originally checked that after reading
|
||||
// the first half of the input, there was nothing left
|
||||
// in the read buffer (buf.buf.Len() != 0) but that is
|
||||
// not necessarily the case: the write Flush may emit
|
||||
// some extra framing bits that are not necessary
|
||||
// to process to obtain the first half of the uncompressed
|
||||
// data. The test ran correctly most of the time, because
|
||||
// the background goroutine had usually read even
|
||||
// those extra bits by now, but it's not a useful thing to
|
||||
// check.
|
||||
buf.WriteMode()
|
||||
}
|
||||
buf.ReadMode()
|
||||
out := make([]byte, 10)
|
||||
if n, err := r.Read(out); n > 0 || err != io.EOF {
|
||||
t.Errorf("testSync (%d, %d, %s): final Read: %d, %v (hex: %x)", level, len(input), name, n, err, out[0:n])
|
||||
}
|
||||
if buf.buf.Len() != 0 {
|
||||
t.Errorf("testSync (%d, %d, %s): extra data at end", level, len(input), name)
|
||||
}
|
||||
r.Close()
|
||||
|
||||
// stream should work for ordinary reader too
|
||||
r = NewReader(buf1)
|
||||
out, err = ioutil.ReadAll(r)
|
||||
if err != nil {
|
||||
t.Errorf("testSync: read: %s", err)
|
||||
return
|
||||
}
|
||||
r.Close()
|
||||
if !bytes.Equal(input, out) {
|
||||
t.Errorf("testSync: decompress(compress(data)) != data: level=%d input=%s", level, name)
|
||||
}
|
||||
}
|
||||
|
||||
func testToFromWithLevelAndLimit(t *testing.T, level int, input []byte, name string, limit int) {
|
||||
var buffer bytes.Buffer
|
||||
w, err := NewWriter(&buffer, level)
|
||||
if err != nil {
|
||||
t.Errorf("NewWriter: %v", err)
|
||||
return
|
||||
}
|
||||
w.Write(input)
|
||||
w.Close()
|
||||
if limit > 0 && buffer.Len() > limit {
|
||||
t.Errorf("level: %d, len(compress(data)) = %d > limit = %d", level, buffer.Len(), limit)
|
||||
return
|
||||
}
|
||||
if limit > 0 {
|
||||
t.Logf("level: %d - Size:%.2f%%, %d b\n", level, float64(buffer.Len()*100)/float64(limit), buffer.Len())
|
||||
}
|
||||
r := NewReader(&buffer)
|
||||
out, err := ioutil.ReadAll(r)
|
||||
if err != nil {
|
||||
t.Errorf("read: %s", err)
|
||||
return
|
||||
}
|
||||
r.Close()
|
||||
if !bytes.Equal(input, out) {
|
||||
t.Errorf("decompress(compress(data)) != data: level=%d input=%s", level, name)
|
||||
return
|
||||
}
|
||||
testSync(t, level, input, name)
|
||||
}
|
||||
|
||||
func testToFromWithLimit(t *testing.T, input []byte, name string, limit [11]int) {
|
||||
for i := 0; i < 10; i++ {
|
||||
testToFromWithLevelAndLimit(t, i, input, name, limit[i])
|
||||
}
|
||||
testToFromWithLevelAndLimit(t, -2, input, name, limit[10])
|
||||
}
|
||||
|
||||
func TestDeflateInflate(t *testing.T) {
|
||||
for i, h := range deflateInflateTests {
|
||||
testToFromWithLimit(t, h.in, fmt.Sprintf("#%d", i), [11]int{})
|
||||
}
|
||||
}
|
||||
|
||||
func TestReverseBits(t *testing.T) {
|
||||
for _, h := range reverseBitsTests {
|
||||
if v := reverseBits(h.in, h.bitCount); v != h.out {
|
||||
t.Errorf("reverseBits(%v,%v) = %v, want %v",
|
||||
h.in, h.bitCount, v, h.out)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
type deflateInflateStringTest struct {
|
||||
filename string
|
||||
label string
|
||||
limit [11]int // Number 11 is ConstantCompression
|
||||
}
|
||||
|
||||
var deflateInflateStringTests = []deflateInflateStringTest{
|
||||
{
|
||||
"../testdata/e.txt",
|
||||
"2.718281828...",
|
||||
[...]int{100018, 67900, 50960, 51150, 50930, 50790, 50790, 50790, 50790, 50790, 43683 + 100},
|
||||
},
|
||||
{
|
||||
"../testdata/Mark.Twain-Tom.Sawyer.txt",
|
||||
"Mark.Twain-Tom.Sawyer",
|
||||
[...]int{387999, 185000, 182361, 179974, 174124, 168819, 162936, 160506, 160295, 160295, 233460 + 100},
|
||||
},
|
||||
}
|
||||
|
||||
func TestDeflateInflateString(t *testing.T) {
|
||||
for _, test := range deflateInflateStringTests {
|
||||
gold, err := ioutil.ReadFile(test.filename)
|
||||
if err != nil {
|
||||
t.Error(err)
|
||||
}
|
||||
// Remove returns that may be present on Windows
|
||||
neutral := strings.Map(func(r rune) rune {
|
||||
if r != '\r' {
|
||||
return r
|
||||
}
|
||||
return -1
|
||||
}, string(gold))
|
||||
|
||||
testToFromWithLimit(t, []byte(neutral), test.label, test.limit)
|
||||
|
||||
if testing.Short() {
|
||||
break
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestReaderDict(t *testing.T) {
|
||||
const (
|
||||
dict = "hello world"
|
||||
text = "hello again world"
|
||||
)
|
||||
var b bytes.Buffer
|
||||
w, err := NewWriter(&b, 5)
|
||||
if err != nil {
|
||||
t.Fatalf("NewWriter: %v", err)
|
||||
}
|
||||
w.Write([]byte(dict))
|
||||
w.Flush()
|
||||
b.Reset()
|
||||
w.Write([]byte(text))
|
||||
w.Close()
|
||||
|
||||
r := NewReaderDict(&b, []byte(dict))
|
||||
data, err := ioutil.ReadAll(r)
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
if string(data) != "hello again world" {
|
||||
t.Fatalf("read returned %q want %q", string(data), text)
|
||||
}
|
||||
}
|
||||
|
||||
func TestWriterDict(t *testing.T) {
|
||||
const (
|
||||
dict = "hello world Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua."
|
||||
text = "hello world Lorem ipsum dolor sit amet"
|
||||
)
|
||||
// This test is sensitive to algorithm changes that skip
|
||||
// data in favour of speed. Higher levels are less prone to this
|
||||
// so we test level 4-9.
|
||||
for l := 4; l < 9; l++ {
|
||||
var b bytes.Buffer
|
||||
w, err := NewWriter(&b, l)
|
||||
if err != nil {
|
||||
t.Fatalf("level %d, NewWriter: %v", l, err)
|
||||
}
|
||||
w.Write([]byte(dict))
|
||||
w.Flush()
|
||||
b.Reset()
|
||||
w.Write([]byte(text))
|
||||
w.Close()
|
||||
|
||||
var b1 bytes.Buffer
|
||||
w, _ = NewWriterDict(&b1, l, []byte(dict))
|
||||
w.Write([]byte(text))
|
||||
w.Close()
|
||||
|
||||
if !bytes.Equal(b1.Bytes(), b.Bytes()) {
|
||||
t.Errorf("level %d, writer wrote\n%v\n want\n%v", l, b1.Bytes(), b.Bytes())
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// See http://code.google.com/p/go/issues/detail?id=2508
|
||||
func TestRegression2508(t *testing.T) {
|
||||
if testing.Short() {
|
||||
t.Logf("test disabled with -short")
|
||||
return
|
||||
}
|
||||
w, err := NewWriter(ioutil.Discard, 1)
|
||||
if err != nil {
|
||||
t.Fatalf("NewWriter: %v", err)
|
||||
}
|
||||
buf := make([]byte, 1024)
|
||||
for i := 0; i < 131072; i++ {
|
||||
if _, err := w.Write(buf); err != nil {
|
||||
t.Fatalf("writer failed: %v", err)
|
||||
}
|
||||
}
|
||||
w.Close()
|
||||
}
|
||||
|
||||
func TestWriterReset(t *testing.T) {
|
||||
for level := -2; level <= 9; level++ {
|
||||
if level == -1 {
|
||||
level++
|
||||
}
|
||||
if testing.Short() && level > 1 {
|
||||
break
|
||||
}
|
||||
w, err := NewWriter(ioutil.Discard, level)
|
||||
if err != nil {
|
||||
t.Fatalf("NewWriter: %v", err)
|
||||
}
|
||||
buf := []byte("hello world")
|
||||
for i := 0; i < 1024; i++ {
|
||||
w.Write(buf)
|
||||
}
|
||||
w.Reset(ioutil.Discard)
|
||||
|
||||
wref, err := NewWriter(ioutil.Discard, level)
|
||||
if err != nil {
|
||||
t.Fatalf("NewWriter: %v", err)
|
||||
}
|
||||
|
||||
// DeepEqual doesn't compare functions.
|
||||
w.d.fill, wref.d.fill = nil, nil
|
||||
w.d.step, wref.d.step = nil, nil
|
||||
w.d.bulkHasher, wref.d.bulkHasher = nil, nil
|
||||
w.d.snap, wref.d.snap = nil, nil
|
||||
|
||||
// hashMatch is always overwritten when used.
|
||||
copy(w.d.hashMatch[:], wref.d.hashMatch[:])
|
||||
if w.d.tokens.n != 0 {
|
||||
t.Errorf("level %d Writer not reset after Reset. %d tokens were present", level, w.d.tokens.n)
|
||||
}
|
||||
// As long as the length is 0, we don't care about the content.
|
||||
w.d.tokens = wref.d.tokens
|
||||
|
||||
// We don't care if there are values in the window, as long as it is at d.index is 0
|
||||
w.d.window = wref.d.window
|
||||
if !reflect.DeepEqual(w, wref) {
|
||||
t.Errorf("level %d Writer not reset after Reset", level)
|
||||
}
|
||||
}
|
||||
testResetOutput(t, func(w io.Writer) (*Writer, error) { return NewWriter(w, NoCompression) })
|
||||
testResetOutput(t, func(w io.Writer) (*Writer, error) { return NewWriter(w, DefaultCompression) })
|
||||
testResetOutput(t, func(w io.Writer) (*Writer, error) { return NewWriter(w, BestCompression) })
|
||||
testResetOutput(t, func(w io.Writer) (*Writer, error) { return NewWriter(w, ConstantCompression) })
|
||||
dict := []byte("we are the world")
|
||||
testResetOutput(t, func(w io.Writer) (*Writer, error) { return NewWriterDict(w, NoCompression, dict) })
|
||||
testResetOutput(t, func(w io.Writer) (*Writer, error) { return NewWriterDict(w, DefaultCompression, dict) })
|
||||
testResetOutput(t, func(w io.Writer) (*Writer, error) { return NewWriterDict(w, BestCompression, dict) })
|
||||
testResetOutput(t, func(w io.Writer) (*Writer, error) { return NewWriterDict(w, ConstantCompression, dict) })
|
||||
}
|
||||
|
||||
func testResetOutput(t *testing.T, newWriter func(w io.Writer) (*Writer, error)) {
|
||||
buf := new(bytes.Buffer)
|
||||
w, err := newWriter(buf)
|
||||
if err != nil {
|
||||
t.Fatalf("NewWriter: %v", err)
|
||||
}
|
||||
b := []byte("hello world")
|
||||
for i := 0; i < 1024; i++ {
|
||||
w.Write(b)
|
||||
}
|
||||
w.Close()
|
||||
out1 := buf.Bytes()
|
||||
|
||||
buf2 := new(bytes.Buffer)
|
||||
w.Reset(buf2)
|
||||
for i := 0; i < 1024; i++ {
|
||||
w.Write(b)
|
||||
}
|
||||
w.Close()
|
||||
out2 := buf2.Bytes()
|
||||
|
||||
if len(out1) != len(out2) {
|
||||
t.Errorf("got %d, expected %d bytes", len(out2), len(out1))
|
||||
}
|
||||
if bytes.Compare(out1, out2) != 0 {
|
||||
mm := 0
|
||||
for i, b := range out1[:len(out2)] {
|
||||
if b != out2[i] {
|
||||
t.Errorf("mismatch index %d: %02x, expected %02x", i, out2[i], b)
|
||||
}
|
||||
mm++
|
||||
if mm == 10 {
|
||||
t.Fatal("Stopping")
|
||||
}
|
||||
}
|
||||
}
|
||||
t.Logf("got %d bytes", len(out1))
|
||||
}
|
||||
|
||||
// TestBestSpeed tests that round-tripping through deflate and then inflate
|
||||
// recovers the original input. The Write sizes are near the thresholds in the
|
||||
// compressor.encSpeed method (0, 16, 128), as well as near maxStoreBlockSize
|
||||
// (65535).
|
||||
func TestBestSpeed(t *testing.T) {
|
||||
abc := make([]byte, 128)
|
||||
for i := range abc {
|
||||
abc[i] = byte(i)
|
||||
}
|
||||
abcabc := bytes.Repeat(abc, 131072/len(abc))
|
||||
var want []byte
|
||||
|
||||
testCases := [][]int{
|
||||
{65536, 0},
|
||||
{65536, 1},
|
||||
{65536, 1, 256},
|
||||
{65536, 1, 65536},
|
||||
{65536, 14},
|
||||
{65536, 15},
|
||||
{65536, 16},
|
||||
{65536, 16, 256},
|
||||
{65536, 16, 65536},
|
||||
{65536, 127},
|
||||
{65536, 128},
|
||||
{65536, 128, 256},
|
||||
{65536, 128, 65536},
|
||||
{65536, 129},
|
||||
{65536, 65536, 256},
|
||||
{65536, 65536, 65536},
|
||||
}
|
||||
|
||||
for i, tc := range testCases {
|
||||
for _, firstN := range []int{1, 65534, 65535, 65536, 65537, 131072} {
|
||||
tc[0] = firstN
|
||||
outer:
|
||||
for _, flush := range []bool{false, true} {
|
||||
buf := new(bytes.Buffer)
|
||||
want = want[:0]
|
||||
|
||||
w, err := NewWriter(buf, BestSpeed)
|
||||
if err != nil {
|
||||
t.Errorf("i=%d, firstN=%d, flush=%t: NewWriter: %v", i, firstN, flush, err)
|
||||
continue
|
||||
}
|
||||
for _, n := range tc {
|
||||
want = append(want, abcabc[:n]...)
|
||||
if _, err := w.Write(abcabc[:n]); err != nil {
|
||||
t.Errorf("i=%d, firstN=%d, flush=%t: Write: %v", i, firstN, flush, err)
|
||||
continue outer
|
||||
}
|
||||
if !flush {
|
||||
continue
|
||||
}
|
||||
if err := w.Flush(); err != nil {
|
||||
t.Errorf("i=%d, firstN=%d, flush=%t: Flush: %v", i, firstN, flush, err)
|
||||
continue outer
|
||||
}
|
||||
}
|
||||
if err := w.Close(); err != nil {
|
||||
t.Errorf("i=%d, firstN=%d, flush=%t: Close: %v", i, firstN, flush, err)
|
||||
continue
|
||||
}
|
||||
|
||||
r := NewReader(buf)
|
||||
got, err := ioutil.ReadAll(r)
|
||||
if err != nil {
|
||||
t.Errorf("i=%d, firstN=%d, flush=%t: ReadAll: %v", i, firstN, flush, err)
|
||||
continue
|
||||
}
|
||||
r.Close()
|
||||
|
||||
if !bytes.Equal(got, want) {
|
||||
t.Errorf("i=%d, firstN=%d, flush=%t: corruption during deflate-then-inflate", i, firstN, flush)
|
||||
continue
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
184
vendor/github.com/klauspost/compress/flate/dict_decoder.go
generated
vendored
Normal file
184
vendor/github.com/klauspost/compress/flate/dict_decoder.go
generated
vendored
Normal file
@@ -0,0 +1,184 @@
|
||||
// Copyright 2016 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package flate
|
||||
|
||||
// dictDecoder implements the LZ77 sliding dictionary as used in decompression.
|
||||
// LZ77 decompresses data through sequences of two forms of commands:
|
||||
//
|
||||
// * Literal insertions: Runs of one or more symbols are inserted into the data
|
||||
// stream as is. This is accomplished through the writeByte method for a
|
||||
// single symbol, or combinations of writeSlice/writeMark for multiple symbols.
|
||||
// Any valid stream must start with a literal insertion if no preset dictionary
|
||||
// is used.
|
||||
//
|
||||
// * Backward copies: Runs of one or more symbols are copied from previously
|
||||
// emitted data. Backward copies come as the tuple (dist, length) where dist
|
||||
// determines how far back in the stream to copy from and length determines how
|
||||
// many bytes to copy. Note that it is valid for the length to be greater than
|
||||
// the distance. Since LZ77 uses forward copies, that situation is used to
|
||||
// perform a form of run-length encoding on repeated runs of symbols.
|
||||
// The writeCopy and tryWriteCopy are used to implement this command.
|
||||
//
|
||||
// For performance reasons, this implementation performs little to no sanity
|
||||
// checks about the arguments. As such, the invariants documented for each
|
||||
// method call must be respected.
|
||||
type dictDecoder struct {
|
||||
hist []byte // Sliding window history
|
||||
|
||||
// Invariant: 0 <= rdPos <= wrPos <= len(hist)
|
||||
wrPos int // Current output position in buffer
|
||||
rdPos int // Have emitted hist[:rdPos] already
|
||||
full bool // Has a full window length been written yet?
|
||||
}
|
||||
|
||||
// init initializes dictDecoder to have a sliding window dictionary of the given
|
||||
// size. If a preset dict is provided, it will initialize the dictionary with
|
||||
// the contents of dict.
|
||||
func (dd *dictDecoder) init(size int, dict []byte) {
|
||||
*dd = dictDecoder{hist: dd.hist}
|
||||
|
||||
if cap(dd.hist) < size {
|
||||
dd.hist = make([]byte, size)
|
||||
}
|
||||
dd.hist = dd.hist[:size]
|
||||
|
||||
if len(dict) > len(dd.hist) {
|
||||
dict = dict[len(dict)-len(dd.hist):]
|
||||
}
|
||||
dd.wrPos = copy(dd.hist, dict)
|
||||
if dd.wrPos == len(dd.hist) {
|
||||
dd.wrPos = 0
|
||||
dd.full = true
|
||||
}
|
||||
dd.rdPos = dd.wrPos
|
||||
}
|
||||
|
||||
// histSize reports the total amount of historical data in the dictionary.
|
||||
func (dd *dictDecoder) histSize() int {
|
||||
if dd.full {
|
||||
return len(dd.hist)
|
||||
}
|
||||
return dd.wrPos
|
||||
}
|
||||
|
||||
// availRead reports the number of bytes that can be flushed by readFlush.
|
||||
func (dd *dictDecoder) availRead() int {
|
||||
return dd.wrPos - dd.rdPos
|
||||
}
|
||||
|
||||
// availWrite reports the available amount of output buffer space.
|
||||
func (dd *dictDecoder) availWrite() int {
|
||||
return len(dd.hist) - dd.wrPos
|
||||
}
|
||||
|
||||
// writeSlice returns a slice of the available buffer to write data to.
|
||||
//
|
||||
// This invariant will be kept: len(s) <= availWrite()
|
||||
func (dd *dictDecoder) writeSlice() []byte {
|
||||
return dd.hist[dd.wrPos:]
|
||||
}
|
||||
|
||||
// writeMark advances the writer pointer by cnt.
|
||||
//
|
||||
// This invariant must be kept: 0 <= cnt <= availWrite()
|
||||
func (dd *dictDecoder) writeMark(cnt int) {
|
||||
dd.wrPos += cnt
|
||||
}
|
||||
|
||||
// writeByte writes a single byte to the dictionary.
|
||||
//
|
||||
// This invariant must be kept: 0 < availWrite()
|
||||
func (dd *dictDecoder) writeByte(c byte) {
|
||||
dd.hist[dd.wrPos] = c
|
||||
dd.wrPos++
|
||||
}
|
||||
|
||||
// writeCopy copies a string at a given (dist, length) to the output.
|
||||
// This returns the number of bytes copied and may be less than the requested
|
||||
// length if the available space in the output buffer is too small.
|
||||
//
|
||||
// This invariant must be kept: 0 < dist <= histSize()
|
||||
func (dd *dictDecoder) writeCopy(dist, length int) int {
|
||||
dstBase := dd.wrPos
|
||||
dstPos := dstBase
|
||||
srcPos := dstPos - dist
|
||||
endPos := dstPos + length
|
||||
if endPos > len(dd.hist) {
|
||||
endPos = len(dd.hist)
|
||||
}
|
||||
|
||||
// Copy non-overlapping section after destination position.
|
||||
//
|
||||
// This section is non-overlapping in that the copy length for this section
|
||||
// is always less than or equal to the backwards distance. This can occur
|
||||
// if a distance refers to data that wraps-around in the buffer.
|
||||
// Thus, a backwards copy is performed here; that is, the exact bytes in
|
||||
// the source prior to the copy is placed in the destination.
|
||||
if srcPos < 0 {
|
||||
srcPos += len(dd.hist)
|
||||
dstPos += copy(dd.hist[dstPos:endPos], dd.hist[srcPos:])
|
||||
srcPos = 0
|
||||
}
|
||||
|
||||
// Copy possibly overlapping section before destination position.
|
||||
//
|
||||
// This section can overlap if the copy length for this section is larger
|
||||
// than the backwards distance. This is allowed by LZ77 so that repeated
|
||||
// strings can be succinctly represented using (dist, length) pairs.
|
||||
// Thus, a forwards copy is performed here; that is, the bytes copied is
|
||||
// possibly dependent on the resulting bytes in the destination as the copy
|
||||
// progresses along. This is functionally equivalent to the following:
|
||||
//
|
||||
// for i := 0; i < endPos-dstPos; i++ {
|
||||
// dd.hist[dstPos+i] = dd.hist[srcPos+i]
|
||||
// }
|
||||
// dstPos = endPos
|
||||
//
|
||||
for dstPos < endPos {
|
||||
dstPos += copy(dd.hist[dstPos:endPos], dd.hist[srcPos:dstPos])
|
||||
}
|
||||
|
||||
dd.wrPos = dstPos
|
||||
return dstPos - dstBase
|
||||
}
|
||||
|
||||
// tryWriteCopy tries to copy a string at a given (distance, length) to the
|
||||
// output. This specialized version is optimized for short distances.
|
||||
//
|
||||
// This method is designed to be inlined for performance reasons.
|
||||
//
|
||||
// This invariant must be kept: 0 < dist <= histSize()
|
||||
func (dd *dictDecoder) tryWriteCopy(dist, length int) int {
|
||||
dstPos := dd.wrPos
|
||||
endPos := dstPos + length
|
||||
if dstPos < dist || endPos > len(dd.hist) {
|
||||
return 0
|
||||
}
|
||||
dstBase := dstPos
|
||||
srcPos := dstPos - dist
|
||||
|
||||
// Copy possibly overlapping section before destination position.
|
||||
loop:
|
||||
dstPos += copy(dd.hist[dstPos:endPos], dd.hist[srcPos:dstPos])
|
||||
if dstPos < endPos {
|
||||
goto loop // Avoid for-loop so that this function can be inlined
|
||||
}
|
||||
|
||||
dd.wrPos = dstPos
|
||||
return dstPos - dstBase
|
||||
}
|
||||
|
||||
// readFlush returns a slice of the historical buffer that is ready to be
|
||||
// emitted to the user. The data returned by readFlush must be fully consumed
|
||||
// before calling any other dictDecoder methods.
|
||||
func (dd *dictDecoder) readFlush() []byte {
|
||||
toRead := dd.hist[dd.rdPos:dd.wrPos]
|
||||
dd.rdPos = dd.wrPos
|
||||
if dd.wrPos == len(dd.hist) {
|
||||
dd.wrPos, dd.rdPos = 0, 0
|
||||
dd.full = true
|
||||
}
|
||||
return toRead
|
||||
}
|
139
vendor/github.com/klauspost/compress/flate/dict_decoder_test.go
generated
vendored
Normal file
139
vendor/github.com/klauspost/compress/flate/dict_decoder_test.go
generated
vendored
Normal file
@@ -0,0 +1,139 @@
|
||||
// Copyright 2016 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package flate
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"strings"
|
||||
"testing"
|
||||
)
|
||||
|
||||
func TestDictDecoder(t *testing.T) {
|
||||
const (
|
||||
abc = "ABC\n"
|
||||
fox = "The quick brown fox jumped over the lazy dog!\n"
|
||||
poem = "The Road Not Taken\nRobert Frost\n" +
|
||||
"\n" +
|
||||
"Two roads diverged in a yellow wood,\n" +
|
||||
"And sorry I could not travel both\n" +
|
||||
"And be one traveler, long I stood\n" +
|
||||
"And looked down one as far as I could\n" +
|
||||
"To where it bent in the undergrowth;\n" +
|
||||
"\n" +
|
||||
"Then took the other, as just as fair,\n" +
|
||||
"And having perhaps the better claim,\n" +
|
||||
"Because it was grassy and wanted wear;\n" +
|
||||
"Though as for that the passing there\n" +
|
||||
"Had worn them really about the same,\n" +
|
||||
"\n" +
|
||||
"And both that morning equally lay\n" +
|
||||
"In leaves no step had trodden black.\n" +
|
||||
"Oh, I kept the first for another day!\n" +
|
||||
"Yet knowing how way leads on to way,\n" +
|
||||
"I doubted if I should ever come back.\n" +
|
||||
"\n" +
|
||||
"I shall be telling this with a sigh\n" +
|
||||
"Somewhere ages and ages hence:\n" +
|
||||
"Two roads diverged in a wood, and I-\n" +
|
||||
"I took the one less traveled by,\n" +
|
||||
"And that has made all the difference.\n"
|
||||
)
|
||||
|
||||
var poemRefs = []struct {
|
||||
dist int // Backward distance (0 if this is an insertion)
|
||||
length int // Length of copy or insertion
|
||||
}{
|
||||
{0, 38}, {33, 3}, {0, 48}, {79, 3}, {0, 11}, {34, 5}, {0, 6}, {23, 7},
|
||||
{0, 8}, {50, 3}, {0, 2}, {69, 3}, {34, 5}, {0, 4}, {97, 3}, {0, 4},
|
||||
{43, 5}, {0, 6}, {7, 4}, {88, 7}, {0, 12}, {80, 3}, {0, 2}, {141, 4},
|
||||
{0, 1}, {196, 3}, {0, 3}, {157, 3}, {0, 6}, {181, 3}, {0, 2}, {23, 3},
|
||||
{77, 3}, {28, 5}, {128, 3}, {110, 4}, {70, 3}, {0, 4}, {85, 6}, {0, 2},
|
||||
{182, 6}, {0, 4}, {133, 3}, {0, 7}, {47, 5}, {0, 20}, {112, 5}, {0, 1},
|
||||
{58, 3}, {0, 8}, {59, 3}, {0, 4}, {173, 3}, {0, 5}, {114, 3}, {0, 4},
|
||||
{92, 5}, {0, 2}, {71, 3}, {0, 2}, {76, 5}, {0, 1}, {46, 3}, {96, 4},
|
||||
{130, 4}, {0, 3}, {360, 3}, {0, 3}, {178, 5}, {0, 7}, {75, 3}, {0, 3},
|
||||
{45, 6}, {0, 6}, {299, 6}, {180, 3}, {70, 6}, {0, 1}, {48, 3}, {66, 4},
|
||||
{0, 3}, {47, 5}, {0, 9}, {325, 3}, {0, 1}, {359, 3}, {318, 3}, {0, 2},
|
||||
{199, 3}, {0, 1}, {344, 3}, {0, 3}, {248, 3}, {0, 10}, {310, 3}, {0, 3},
|
||||
{93, 6}, {0, 3}, {252, 3}, {157, 4}, {0, 2}, {273, 5}, {0, 14}, {99, 4},
|
||||
{0, 1}, {464, 4}, {0, 2}, {92, 4}, {495, 3}, {0, 1}, {322, 4}, {16, 4},
|
||||
{0, 3}, {402, 3}, {0, 2}, {237, 4}, {0, 2}, {432, 4}, {0, 1}, {483, 5},
|
||||
{0, 2}, {294, 4}, {0, 2}, {306, 3}, {113, 5}, {0, 1}, {26, 4}, {164, 3},
|
||||
{488, 4}, {0, 1}, {542, 3}, {248, 6}, {0, 5}, {205, 3}, {0, 8}, {48, 3},
|
||||
{449, 6}, {0, 2}, {192, 3}, {328, 4}, {9, 5}, {433, 3}, {0, 3}, {622, 25},
|
||||
{615, 5}, {46, 5}, {0, 2}, {104, 3}, {475, 10}, {549, 3}, {0, 4}, {597, 8},
|
||||
{314, 3}, {0, 1}, {473, 6}, {317, 5}, {0, 1}, {400, 3}, {0, 3}, {109, 3},
|
||||
{151, 3}, {48, 4}, {0, 4}, {125, 3}, {108, 3}, {0, 2},
|
||||
}
|
||||
|
||||
var got, want bytes.Buffer
|
||||
var dd dictDecoder
|
||||
dd.init(1<<11, nil)
|
||||
|
||||
var writeCopy = func(dist, length int) {
|
||||
for length > 0 {
|
||||
cnt := dd.tryWriteCopy(dist, length)
|
||||
if cnt == 0 {
|
||||
cnt = dd.writeCopy(dist, length)
|
||||
}
|
||||
|
||||
length -= cnt
|
||||
if dd.availWrite() == 0 {
|
||||
got.Write(dd.readFlush())
|
||||
}
|
||||
}
|
||||
}
|
||||
var writeString = func(str string) {
|
||||
for len(str) > 0 {
|
||||
cnt := copy(dd.writeSlice(), str)
|
||||
str = str[cnt:]
|
||||
dd.writeMark(cnt)
|
||||
if dd.availWrite() == 0 {
|
||||
got.Write(dd.readFlush())
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
writeString(".")
|
||||
want.WriteByte('.')
|
||||
|
||||
str := poem
|
||||
for _, ref := range poemRefs {
|
||||
if ref.dist == 0 {
|
||||
writeString(str[:ref.length])
|
||||
} else {
|
||||
writeCopy(ref.dist, ref.length)
|
||||
}
|
||||
str = str[ref.length:]
|
||||
}
|
||||
want.WriteString(poem)
|
||||
|
||||
writeCopy(dd.histSize(), 33)
|
||||
want.Write(want.Bytes()[:33])
|
||||
|
||||
writeString(abc)
|
||||
writeCopy(len(abc), 59*len(abc))
|
||||
want.WriteString(strings.Repeat(abc, 60))
|
||||
|
||||
writeString(fox)
|
||||
writeCopy(len(fox), 9*len(fox))
|
||||
want.WriteString(strings.Repeat(fox, 10))
|
||||
|
||||
writeString(".")
|
||||
writeCopy(1, 9)
|
||||
want.WriteString(strings.Repeat(".", 10))
|
||||
|
||||
writeString(strings.ToUpper(poem))
|
||||
writeCopy(len(poem), 7*len(poem))
|
||||
want.WriteString(strings.Repeat(strings.ToUpper(poem), 8))
|
||||
|
||||
writeCopy(dd.histSize(), 10)
|
||||
want.Write(want.Bytes()[want.Len()-dd.histSize():][:10])
|
||||
|
||||
got.Write(dd.readFlush())
|
||||
if got.String() != want.String() {
|
||||
t.Errorf("final string mismatch:\ngot %q\nwant %q", got.String(), want.String())
|
||||
}
|
||||
}
|
260
vendor/github.com/klauspost/compress/flate/flate_test.go
generated
vendored
Normal file
260
vendor/github.com/klauspost/compress/flate/flate_test.go
generated
vendored
Normal file
@@ -0,0 +1,260 @@
|
||||
// Copyright 2009 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
// This test tests some internals of the flate package.
|
||||
// The tests in package compress/gzip serve as the
|
||||
// end-to-end test of the decompressor.
|
||||
|
||||
package flate
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"encoding/hex"
|
||||
"io/ioutil"
|
||||
"testing"
|
||||
)
|
||||
|
||||
// The following test should not panic.
|
||||
func TestIssue5915(t *testing.T) {
|
||||
bits := []int{4, 0, 0, 6, 4, 3, 2, 3, 3, 4, 4, 5, 0, 0, 0, 0, 5, 5, 6,
|
||||
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 11, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
|
||||
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, 8, 6, 0, 11, 0, 8, 0, 6, 6, 10, 8}
|
||||
var h huffmanDecoder
|
||||
if h.init(bits) {
|
||||
t.Fatalf("Given sequence of bits is bad, and should not succeed.")
|
||||
}
|
||||
}
|
||||
|
||||
// The following test should not panic.
|
||||
func TestIssue5962(t *testing.T) {
|
||||
bits := []int{4, 0, 0, 6, 4, 3, 2, 3, 3, 4, 4, 5, 0, 0, 0, 0,
|
||||
5, 5, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 11}
|
||||
var h huffmanDecoder
|
||||
if h.init(bits) {
|
||||
t.Fatalf("Given sequence of bits is bad, and should not succeed.")
|
||||
}
|
||||
}
|
||||
|
||||
// The following test should not panic.
|
||||
func TestIssue6255(t *testing.T) {
|
||||
bits1 := []int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 11}
|
||||
bits2 := []int{11, 13}
|
||||
var h huffmanDecoder
|
||||
if !h.init(bits1) {
|
||||
t.Fatalf("Given sequence of bits is good and should succeed.")
|
||||
}
|
||||
if h.init(bits2) {
|
||||
t.Fatalf("Given sequence of bits is bad and should not succeed.")
|
||||
}
|
||||
}
|
||||
|
||||
func TestInvalidEncoding(t *testing.T) {
|
||||
// Initialize Huffman decoder to recognize "0".
|
||||
var h huffmanDecoder
|
||||
if !h.init([]int{1}) {
|
||||
t.Fatal("Failed to initialize Huffman decoder")
|
||||
}
|
||||
|
||||
// Initialize decompressor with invalid Huffman coding.
|
||||
var f decompressor
|
||||
f.r = bytes.NewReader([]byte{0xff})
|
||||
|
||||
_, err := f.huffSym(&h)
|
||||
if err == nil {
|
||||
t.Fatal("Should have rejected invalid bit sequence")
|
||||
}
|
||||
}
|
||||
|
||||
func TestInvalidBits(t *testing.T) {
|
||||
oversubscribed := []int{1, 2, 3, 4, 4, 5}
|
||||
incomplete := []int{1, 2, 4, 4}
|
||||
var h huffmanDecoder
|
||||
if h.init(oversubscribed) {
|
||||
t.Fatal("Should reject oversubscribed bit-length set")
|
||||
}
|
||||
if h.init(incomplete) {
|
||||
t.Fatal("Should reject incomplete bit-length set")
|
||||
}
|
||||
}
|
||||
|
||||
func TestStreams(t *testing.T) {
|
||||
// To verify any of these hexstrings as valid or invalid flate streams
|
||||
// according to the C zlib library, you can use the Python wrapper library:
|
||||
// >>> hex_string = "010100feff11"
|
||||
// >>> import zlib
|
||||
// >>> zlib.decompress(hex_string.decode("hex"), -15) # Negative means raw DEFLATE
|
||||
// '\x11'
|
||||
|
||||
testCases := []struct {
|
||||
desc string // Description of the stream
|
||||
stream string // Hexstring of the input DEFLATE stream
|
||||
want string // Expected result. Use "fail" to expect failure
|
||||
}{{
|
||||
"degenerate HCLenTree",
|
||||
"05e0010000000000100000000000000000000000000000000000000000000000" +
|
||||
"00000000000000000004",
|
||||
"fail",
|
||||
}, {
|
||||
"complete HCLenTree, empty HLitTree, empty HDistTree",
|
||||
"05e0010400000000000000000000000000000000000000000000000000000000" +
|
||||
"00000000000000000010",
|
||||
"fail",
|
||||
}, {
|
||||
"empty HCLenTree",
|
||||
"05e0010000000000000000000000000000000000000000000000000000000000" +
|
||||
"00000000000000000010",
|
||||
"fail",
|
||||
}, {
|
||||
"complete HCLenTree, complete HLitTree, empty HDistTree, use missing HDist symbol",
|
||||
"000100feff000de0010400000000100000000000000000000000000000000000" +
|
||||
"0000000000000000000000000000002c",
|
||||
"fail",
|
||||
}, {
|
||||
"complete HCLenTree, complete HLitTree, degenerate HDistTree, use missing HDist symbol",
|
||||
"000100feff000de0010000000000000000000000000000000000000000000000" +
|
||||
"00000000000000000610000000004070",
|
||||
"fail",
|
||||
}, {
|
||||
"complete HCLenTree, empty HLitTree, empty HDistTree",
|
||||
"05e0010400000000100400000000000000000000000000000000000000000000" +
|
||||
"0000000000000000000000000008",
|
||||
"fail",
|
||||
}, {
|
||||
"complete HCLenTree, empty HLitTree, degenerate HDistTree",
|
||||
"05e0010400000000100400000000000000000000000000000000000000000000" +
|
||||
"0000000000000000000800000008",
|
||||
"fail",
|
||||
}, {
|
||||
"complete HCLenTree, degenerate HLitTree, degenerate HDistTree, use missing HLit symbol",
|
||||
"05e0010400000000100000000000000000000000000000000000000000000000" +
|
||||
"0000000000000000001c",
|
||||
"fail",
|
||||
}, {
|
||||
"complete HCLenTree, complete HLitTree, too large HDistTree",
|
||||
"edff870500000000200400000000000000000000000000000000000000000000" +
|
||||
"000000000000000000080000000000000004",
|
||||
"fail",
|
||||
}, {
|
||||
"complete HCLenTree, complete HLitTree, empty HDistTree, excessive repeater code",
|
||||
"edfd870500000000200400000000000000000000000000000000000000000000" +
|
||||
"000000000000000000e8b100",
|
||||
"fail",
|
||||
}, {
|
||||
"complete HCLenTree, complete HLitTree, empty HDistTree of normal length 30",
|
||||
"05fd01240000000000f8ffffffffffffffffffffffffffffffffffffffffffff" +
|
||||
"ffffffffffffffffff07000000fe01",
|
||||
"",
|
||||
}, {
|
||||
"complete HCLenTree, complete HLitTree, empty HDistTree of excessive length 31",
|
||||
"05fe01240000000000f8ffffffffffffffffffffffffffffffffffffffffffff" +
|
||||
"ffffffffffffffffff07000000fc03",
|
||||
"fail",
|
||||
}, {
|
||||
"complete HCLenTree, over-subscribed HLitTree, empty HDistTree",
|
||||
"05e001240000000000fcffffffffffffffffffffffffffffffffffffffffffff" +
|
||||
"ffffffffffffffffff07f00f",
|
||||
"fail",
|
||||
}, {
|
||||
"complete HCLenTree, under-subscribed HLitTree, empty HDistTree",
|
||||
"05e001240000000000fcffffffffffffffffffffffffffffffffffffffffffff" +
|
||||
"fffffffffcffffffff07f00f",
|
||||
"fail",
|
||||
}, {
|
||||
"complete HCLenTree, complete HLitTree with single code, empty HDistTree",
|
||||
"05e001240000000000f8ffffffffffffffffffffffffffffffffffffffffffff" +
|
||||
"ffffffffffffffffff07f00f",
|
||||
"01",
|
||||
}, {
|
||||
"complete HCLenTree, complete HLitTree with multiple codes, empty HDistTree",
|
||||
"05e301240000000000f8ffffffffffffffffffffffffffffffffffffffffffff" +
|
||||
"ffffffffffffffffff07807f",
|
||||
"01",
|
||||
}, {
|
||||
"complete HCLenTree, complete HLitTree, degenerate HDistTree, use valid HDist symbol",
|
||||
"000100feff000de0010400000000100000000000000000000000000000000000" +
|
||||
"0000000000000000000000000000003c",
|
||||
"00000000",
|
||||
}, {
|
||||
"complete HCLenTree, degenerate HLitTree, degenerate HDistTree",
|
||||
"05e0010400000000100000000000000000000000000000000000000000000000" +
|
||||
"0000000000000000000c",
|
||||
"",
|
||||
}, {
|
||||
"complete HCLenTree, degenerate HLitTree, empty HDistTree",
|
||||
"05e0010400000000100000000000000000000000000000000000000000000000" +
|
||||
"00000000000000000004",
|
||||
"",
|
||||
}, {
|
||||
"complete HCLenTree, complete HLitTree, empty HDistTree, spanning repeater code",
|
||||
"edfd870500000000200400000000000000000000000000000000000000000000" +
|
||||
"000000000000000000e8b000",
|
||||
"",
|
||||
}, {
|
||||
"complete HCLenTree with length codes, complete HLitTree, empty HDistTree",
|
||||
"ede0010400000000100000000000000000000000000000000000000000000000" +
|
||||
"0000000000000000000400004000",
|
||||
"",
|
||||
}, {
|
||||
"complete HCLenTree, complete HLitTree, degenerate HDistTree, use valid HLit symbol 284 with count 31",
|
||||
"000100feff00ede0010400000000100000000000000000000000000000000000" +
|
||||
"000000000000000000000000000000040000407f00",
|
||||
"0000000000000000000000000000000000000000000000000000000000000000" +
|
||||
"0000000000000000000000000000000000000000000000000000000000000000" +
|
||||
"0000000000000000000000000000000000000000000000000000000000000000" +
|
||||
"0000000000000000000000000000000000000000000000000000000000000000" +
|
||||
"0000000000000000000000000000000000000000000000000000000000000000" +
|
||||
"0000000000000000000000000000000000000000000000000000000000000000" +
|
||||
"0000000000000000000000000000000000000000000000000000000000000000" +
|
||||
"0000000000000000000000000000000000000000000000000000000000000000" +
|
||||
"000000",
|
||||
}, {
|
||||
"complete HCLenTree, complete HLitTree, degenerate HDistTree, use valid HLit and HDist symbols",
|
||||
"0cc2010d00000082b0ac4aff0eb07d27060000ffff",
|
||||
"616263616263",
|
||||
}, {
|
||||
"fixed block, use reserved symbol 287",
|
||||
"33180700",
|
||||
"fail",
|
||||
}, {
|
||||
"raw block",
|
||||
"010100feff11",
|
||||
"11",
|
||||
}, {
|
||||
"issue 10426 - over-subscribed HCLenTree causes a hang",
|
||||
"344c4a4e494d4b070000ff2e2eff2e2e2e2e2eff",
|
||||
"fail",
|
||||
}, {
|
||||
"issue 11030 - empty HDistTree unexpectedly leads to error",
|
||||
"05c0070600000080400fff37a0ca",
|
||||
"",
|
||||
}, {
|
||||
"issue 11033 - empty HDistTree unexpectedly leads to error",
|
||||
"050fb109c020cca5d017dcbca044881ee1034ec149c8980bbc413c2ab35be9dc" +
|
||||
"b1473449922449922411202306ee97b0383a521b4ffdcf3217f9f7d3adb701",
|
||||
"3130303634342068652e706870005d05355f7ed957ff084a90925d19e3ebc6d0" +
|
||||
"c6d7",
|
||||
}}
|
||||
|
||||
for i, tc := range testCases {
|
||||
data, err := hex.DecodeString(tc.stream)
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
data, err = ioutil.ReadAll(NewReader(bytes.NewReader(data)))
|
||||
if tc.want == "fail" {
|
||||
if err == nil {
|
||||
t.Errorf("#%d (%s): got nil error, want non-nil", i, tc.desc)
|
||||
}
|
||||
} else {
|
||||
if err != nil {
|
||||
t.Errorf("#%d (%s): %v", i, tc.desc, err)
|
||||
continue
|
||||
}
|
||||
if got := hex.EncodeToString(data); got != tc.want {
|
||||
t.Errorf("#%d (%s):\ngot %q\nwant %q", i, tc.desc, got, tc.want)
|
||||
}
|
||||
|
||||
}
|
||||
}
|
||||
}
|
265
vendor/github.com/klauspost/compress/flate/gen.go
generated
vendored
Normal file
265
vendor/github.com/klauspost/compress/flate/gen.go
generated
vendored
Normal file
@@ -0,0 +1,265 @@
|
||||
// Copyright 2012 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
// +build ignore
|
||||
|
||||
// This program generates fixedhuff.go
|
||||
// Invoke as
|
||||
//
|
||||
// go run gen.go -output fixedhuff.go
|
||||
|
||||
package main
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"flag"
|
||||
"fmt"
|
||||
"go/format"
|
||||
"io/ioutil"
|
||||
"log"
|
||||
)
|
||||
|
||||
var filename = flag.String("output", "fixedhuff.go", "output file name")
|
||||
|
||||
const maxCodeLen = 16
|
||||
|
||||
// Note: the definition of the huffmanDecoder struct is copied from
|
||||
// inflate.go, as it is private to the implementation.
|
||||
|
||||
// chunk & 15 is number of bits
|
||||
// chunk >> 4 is value, including table link
|
||||
|
||||
const (
|
||||
huffmanChunkBits = 9
|
||||
huffmanNumChunks = 1 << huffmanChunkBits
|
||||
huffmanCountMask = 15
|
||||
huffmanValueShift = 4
|
||||
)
|
||||
|
||||
type huffmanDecoder struct {
|
||||
min int // the minimum code length
|
||||
chunks [huffmanNumChunks]uint32 // chunks as described above
|
||||
links [][]uint32 // overflow links
|
||||
linkMask uint32 // mask the width of the link table
|
||||
}
|
||||
|
||||
// Initialize Huffman decoding tables from array of code lengths.
|
||||
// Following this function, h is guaranteed to be initialized into a complete
|
||||
// tree (i.e., neither over-subscribed nor under-subscribed). The exception is a
|
||||
// degenerate case where the tree has only a single symbol with length 1. Empty
|
||||
// trees are permitted.
|
||||
func (h *huffmanDecoder) init(bits []int) bool {
|
||||
// Sanity enables additional runtime tests during Huffman
|
||||
// table construction. It's intended to be used during
|
||||
// development to supplement the currently ad-hoc unit tests.
|
||||
const sanity = false
|
||||
|
||||
if h.min != 0 {
|
||||
*h = huffmanDecoder{}
|
||||
}
|
||||
|
||||
// Count number of codes of each length,
|
||||
// compute min and max length.
|
||||
var count [maxCodeLen]int
|
||||
var min, max int
|
||||
for _, n := range bits {
|
||||
if n == 0 {
|
||||
continue
|
||||
}
|
||||
if min == 0 || n < min {
|
||||
min = n
|
||||
}
|
||||
if n > max {
|
||||
max = n
|
||||
}
|
||||
count[n]++
|
||||
}
|
||||
|
||||
// Empty tree. The decompressor.huffSym function will fail later if the tree
|
||||
// is used. Technically, an empty tree is only valid for the HDIST tree and
|
||||
// not the HCLEN and HLIT tree. However, a stream with an empty HCLEN tree
|
||||
// is guaranteed to fail since it will attempt to use the tree to decode the
|
||||
// codes for the HLIT and HDIST trees. Similarly, an empty HLIT tree is
|
||||
// guaranteed to fail later since the compressed data section must be
|
||||
// composed of at least one symbol (the end-of-block marker).
|
||||
if max == 0 {
|
||||
return true
|
||||
}
|
||||
|
||||
code := 0
|
||||
var nextcode [maxCodeLen]int
|
||||
for i := min; i <= max; i++ {
|
||||
code <<= 1
|
||||
nextcode[i] = code
|
||||
code += count[i]
|
||||
}
|
||||
|
||||
// Check that the coding is complete (i.e., that we've
|
||||
// assigned all 2-to-the-max possible bit sequences).
|
||||
// Exception: To be compatible with zlib, we also need to
|
||||
// accept degenerate single-code codings. See also
|
||||
// TestDegenerateHuffmanCoding.
|
||||
if code != 1<<uint(max) && !(code == 1 && max == 1) {
|
||||
return false
|
||||
}
|
||||
|
||||
h.min = min
|
||||
if max > huffmanChunkBits {
|
||||
numLinks := 1 << (uint(max) - huffmanChunkBits)
|
||||
h.linkMask = uint32(numLinks - 1)
|
||||
|
||||
// create link tables
|
||||
link := nextcode[huffmanChunkBits+1] >> 1
|
||||
h.links = make([][]uint32, huffmanNumChunks-link)
|
||||
for j := uint(link); j < huffmanNumChunks; j++ {
|
||||
reverse := int(reverseByte[j>>8]) | int(reverseByte[j&0xff])<<8
|
||||
reverse >>= uint(16 - huffmanChunkBits)
|
||||
off := j - uint(link)
|
||||
if sanity && h.chunks[reverse] != 0 {
|
||||
panic("impossible: overwriting existing chunk")
|
||||
}
|
||||
h.chunks[reverse] = uint32(off<<huffmanValueShift | (huffmanChunkBits + 1))
|
||||
h.links[off] = make([]uint32, numLinks)
|
||||
}
|
||||
}
|
||||
|
||||
for i, n := range bits {
|
||||
if n == 0 {
|
||||
continue
|
||||
}
|
||||
code := nextcode[n]
|
||||
nextcode[n]++
|
||||
chunk := uint32(i<<huffmanValueShift | n)
|
||||
reverse := int(reverseByte[code>>8]) | int(reverseByte[code&0xff])<<8
|
||||
reverse >>= uint(16 - n)
|
||||
if n <= huffmanChunkBits {
|
||||
for off := reverse; off < len(h.chunks); off += 1 << uint(n) {
|
||||
// We should never need to overwrite
|
||||
// an existing chunk. Also, 0 is
|
||||
// never a valid chunk, because the
|
||||
// lower 4 "count" bits should be
|
||||
// between 1 and 15.
|
||||
if sanity && h.chunks[off] != 0 {
|
||||
panic("impossible: overwriting existing chunk")
|
||||
}
|
||||
h.chunks[off] = chunk
|
||||
}
|
||||
} else {
|
||||
j := reverse & (huffmanNumChunks - 1)
|
||||
if sanity && h.chunks[j]&huffmanCountMask != huffmanChunkBits+1 {
|
||||
// Longer codes should have been
|
||||
// associated with a link table above.
|
||||
panic("impossible: not an indirect chunk")
|
||||
}
|
||||
value := h.chunks[j] >> huffmanValueShift
|
||||
linktab := h.links[value]
|
||||
reverse >>= huffmanChunkBits
|
||||
for off := reverse; off < len(linktab); off += 1 << uint(n-huffmanChunkBits) {
|
||||
if sanity && linktab[off] != 0 {
|
||||
panic("impossible: overwriting existing chunk")
|
||||
}
|
||||
linktab[off] = chunk
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if sanity {
|
||||
// Above we've sanity checked that we never overwrote
|
||||
// an existing entry. Here we additionally check that
|
||||
// we filled the tables completely.
|
||||
for i, chunk := range h.chunks {
|
||||
if chunk == 0 {
|
||||
// As an exception, in the degenerate
|
||||
// single-code case, we allow odd
|
||||
// chunks to be missing.
|
||||
if code == 1 && i%2 == 1 {
|
||||
continue
|
||||
}
|
||||
panic("impossible: missing chunk")
|
||||
}
|
||||
}
|
||||
for _, linktab := range h.links {
|
||||
for _, chunk := range linktab {
|
||||
if chunk == 0 {
|
||||
panic("impossible: missing chunk")
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return true
|
||||
}
|
||||
|
||||
func main() {
|
||||
flag.Parse()
|
||||
|
||||
var h huffmanDecoder
|
||||
var bits [288]int
|
||||
initReverseByte()
|
||||
for i := 0; i < 144; i++ {
|
||||
bits[i] = 8
|
||||
}
|
||||
for i := 144; i < 256; i++ {
|
||||
bits[i] = 9
|
||||
}
|
||||
for i := 256; i < 280; i++ {
|
||||
bits[i] = 7
|
||||
}
|
||||
for i := 280; i < 288; i++ {
|
||||
bits[i] = 8
|
||||
}
|
||||
h.init(bits[:])
|
||||
if h.links != nil {
|
||||
log.Fatal("Unexpected links table in fixed Huffman decoder")
|
||||
}
|
||||
|
||||
var buf bytes.Buffer
|
||||
|
||||
fmt.Fprintf(&buf, `// Copyright 2013 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.`+"\n\n")
|
||||
|
||||
fmt.Fprintln(&buf, "package flate")
|
||||
fmt.Fprintln(&buf)
|
||||
fmt.Fprintln(&buf, "// autogenerated by go run gen.go -output fixedhuff.go, DO NOT EDIT")
|
||||
fmt.Fprintln(&buf)
|
||||
fmt.Fprintln(&buf, "var fixedHuffmanDecoder = huffmanDecoder{")
|
||||
fmt.Fprintf(&buf, "\t%d,\n", h.min)
|
||||
fmt.Fprintln(&buf, "\t[huffmanNumChunks]uint32{")
|
||||
for i := 0; i < huffmanNumChunks; i++ {
|
||||
if i&7 == 0 {
|
||||
fmt.Fprintf(&buf, "\t\t")
|
||||
} else {
|
||||
fmt.Fprintf(&buf, " ")
|
||||
}
|
||||
fmt.Fprintf(&buf, "0x%04x,", h.chunks[i])
|
||||
if i&7 == 7 {
|
||||
fmt.Fprintln(&buf)
|
||||
}
|
||||
}
|
||||
fmt.Fprintln(&buf, "\t},")
|
||||
fmt.Fprintln(&buf, "\tnil, 0,")
|
||||
fmt.Fprintln(&buf, "}")
|
||||
|
||||
data, err := format.Source(buf.Bytes())
|
||||
if err != nil {
|
||||
log.Fatal(err)
|
||||
}
|
||||
err = ioutil.WriteFile(*filename, data, 0644)
|
||||
if err != nil {
|
||||
log.Fatal(err)
|
||||
}
|
||||
}
|
||||
|
||||
var reverseByte [256]byte
|
||||
|
||||
func initReverseByte() {
|
||||
for x := 0; x < 256; x++ {
|
||||
var result byte
|
||||
for i := uint(0); i < 8; i++ {
|
||||
result |= byte(((x >> i) & 1) << (7 - i))
|
||||
}
|
||||
reverseByte[x] = result
|
||||
}
|
||||
}
|
701
vendor/github.com/klauspost/compress/flate/huffman_bit_writer.go
generated
vendored
Normal file
701
vendor/github.com/klauspost/compress/flate/huffman_bit_writer.go
generated
vendored
Normal file
@@ -0,0 +1,701 @@
|
||||
// Copyright 2009 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package flate
|
||||
|
||||
import (
|
||||
"io"
|
||||
)
|
||||
|
||||
const (
|
||||
// The largest offset code.
|
||||
offsetCodeCount = 30
|
||||
|
||||
// The special code used to mark the end of a block.
|
||||
endBlockMarker = 256
|
||||
|
||||
// The first length code.
|
||||
lengthCodesStart = 257
|
||||
|
||||
// The number of codegen codes.
|
||||
codegenCodeCount = 19
|
||||
badCode = 255
|
||||
|
||||
// bufferFlushSize indicates the buffer size
|
||||
// after which bytes are flushed to the writer.
|
||||
// Should preferably be a multiple of 6, since
|
||||
// we accumulate 6 bytes between writes to the buffer.
|
||||
bufferFlushSize = 240
|
||||
|
||||
// bufferSize is the actual output byte buffer size.
|
||||
// It must have additional headroom for a flush
|
||||
// which can contain up to 8 bytes.
|
||||
bufferSize = bufferFlushSize + 8
|
||||
)
|
||||
|
||||
// The number of extra bits needed by length code X - LENGTH_CODES_START.
|
||||
var lengthExtraBits = []int8{
|
||||
/* 257 */ 0, 0, 0,
|
||||
/* 260 */ 0, 0, 0, 0, 0, 1, 1, 1, 1, 2,
|
||||
/* 270 */ 2, 2, 2, 3, 3, 3, 3, 4, 4, 4,
|
||||
/* 280 */ 4, 5, 5, 5, 5, 0,
|
||||
}
|
||||
|
||||
// The length indicated by length code X - LENGTH_CODES_START.
|
||||
var lengthBase = []uint32{
|
||||
0, 1, 2, 3, 4, 5, 6, 7, 8, 10,
|
||||
12, 14, 16, 20, 24, 28, 32, 40, 48, 56,
|
||||
64, 80, 96, 112, 128, 160, 192, 224, 255,
|
||||
}
|
||||
|
||||
// offset code word extra bits.
|
||||
var offsetExtraBits = []int8{
|
||||
0, 0, 0, 0, 1, 1, 2, 2, 3, 3,
|
||||
4, 4, 5, 5, 6, 6, 7, 7, 8, 8,
|
||||
9, 9, 10, 10, 11, 11, 12, 12, 13, 13,
|
||||
/* extended window */
|
||||
14, 14, 15, 15, 16, 16, 17, 17, 18, 18, 19, 19, 20, 20,
|
||||
}
|
||||
|
||||
var offsetBase = []uint32{
|
||||
/* normal deflate */
|
||||
0x000000, 0x000001, 0x000002, 0x000003, 0x000004,
|
||||
0x000006, 0x000008, 0x00000c, 0x000010, 0x000018,
|
||||
0x000020, 0x000030, 0x000040, 0x000060, 0x000080,
|
||||
0x0000c0, 0x000100, 0x000180, 0x000200, 0x000300,
|
||||
0x000400, 0x000600, 0x000800, 0x000c00, 0x001000,
|
||||
0x001800, 0x002000, 0x003000, 0x004000, 0x006000,
|
||||
|
||||
/* extended window */
|
||||
0x008000, 0x00c000, 0x010000, 0x018000, 0x020000,
|
||||
0x030000, 0x040000, 0x060000, 0x080000, 0x0c0000,
|
||||
0x100000, 0x180000, 0x200000, 0x300000,
|
||||
}
|
||||
|
||||
// The odd order in which the codegen code sizes are written.
|
||||
var codegenOrder = []uint32{16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}
|
||||
|
||||
type huffmanBitWriter struct {
|
||||
// writer is the underlying writer.
|
||||
// Do not use it directly; use the write method, which ensures
|
||||
// that Write errors are sticky.
|
||||
writer io.Writer
|
||||
|
||||
// Data waiting to be written is bytes[0:nbytes]
|
||||
// and then the low nbits of bits.
|
||||
bits uint64
|
||||
nbits uint
|
||||
bytes [bufferSize]byte
|
||||
codegenFreq [codegenCodeCount]int32
|
||||
nbytes int
|
||||
literalFreq []int32
|
||||
offsetFreq []int32
|
||||
codegen []uint8
|
||||
literalEncoding *huffmanEncoder
|
||||
offsetEncoding *huffmanEncoder
|
||||
codegenEncoding *huffmanEncoder
|
||||
err error
|
||||
}
|
||||
|
||||
func newHuffmanBitWriter(w io.Writer) *huffmanBitWriter {
|
||||
return &huffmanBitWriter{
|
||||
writer: w,
|
||||
literalFreq: make([]int32, maxNumLit),
|
||||
offsetFreq: make([]int32, offsetCodeCount),
|
||||
codegen: make([]uint8, maxNumLit+offsetCodeCount+1),
|
||||
literalEncoding: newHuffmanEncoder(maxNumLit),
|
||||
codegenEncoding: newHuffmanEncoder(codegenCodeCount),
|
||||
offsetEncoding: newHuffmanEncoder(offsetCodeCount),
|
||||
}
|
||||
}
|
||||
|
||||
func (w *huffmanBitWriter) reset(writer io.Writer) {
|
||||
w.writer = writer
|
||||
w.bits, w.nbits, w.nbytes, w.err = 0, 0, 0, nil
|
||||
w.bytes = [bufferSize]byte{}
|
||||
}
|
||||
|
||||
func (w *huffmanBitWriter) flush() {
|
||||
if w.err != nil {
|
||||
w.nbits = 0
|
||||
return
|
||||
}
|
||||
n := w.nbytes
|
||||
for w.nbits != 0 {
|
||||
w.bytes[n] = byte(w.bits)
|
||||
w.bits >>= 8
|
||||
if w.nbits > 8 { // Avoid underflow
|
||||
w.nbits -= 8
|
||||
} else {
|
||||
w.nbits = 0
|
||||
}
|
||||
n++
|
||||
}
|
||||
w.bits = 0
|
||||
w.write(w.bytes[:n])
|
||||
w.nbytes = 0
|
||||
}
|
||||
|
||||
func (w *huffmanBitWriter) write(b []byte) {
|
||||
if w.err != nil {
|
||||
return
|
||||
}
|
||||
_, w.err = w.writer.Write(b)
|
||||
}
|
||||
|
||||
func (w *huffmanBitWriter) writeBits(b int32, nb uint) {
|
||||
if w.err != nil {
|
||||
return
|
||||
}
|
||||
w.bits |= uint64(b) << w.nbits
|
||||
w.nbits += nb
|
||||
if w.nbits >= 48 {
|
||||
bits := w.bits
|
||||
w.bits >>= 48
|
||||
w.nbits -= 48
|
||||
n := w.nbytes
|
||||
bytes := w.bytes[n : n+6]
|
||||
bytes[0] = byte(bits)
|
||||
bytes[1] = byte(bits >> 8)
|
||||
bytes[2] = byte(bits >> 16)
|
||||
bytes[3] = byte(bits >> 24)
|
||||
bytes[4] = byte(bits >> 32)
|
||||
bytes[5] = byte(bits >> 40)
|
||||
n += 6
|
||||
if n >= bufferFlushSize {
|
||||
w.write(w.bytes[:n])
|
||||
n = 0
|
||||
}
|
||||
w.nbytes = n
|
||||
}
|
||||
}
|
||||
|
||||
func (w *huffmanBitWriter) writeBytes(bytes []byte) {
|
||||
if w.err != nil {
|
||||
return
|
||||
}
|
||||
n := w.nbytes
|
||||
if w.nbits&7 != 0 {
|
||||
w.err = InternalError("writeBytes with unfinished bits")
|
||||
return
|
||||
}
|
||||
for w.nbits != 0 {
|
||||
w.bytes[n] = byte(w.bits)
|
||||
w.bits >>= 8
|
||||
w.nbits -= 8
|
||||
n++
|
||||
}
|
||||
if n != 0 {
|
||||
w.write(w.bytes[:n])
|
||||
}
|
||||
w.nbytes = 0
|
||||
w.write(bytes)
|
||||
}
|
||||
|
||||
// RFC 1951 3.2.7 specifies a special run-length encoding for specifying
|
||||
// the literal and offset lengths arrays (which are concatenated into a single
|
||||
// array). This method generates that run-length encoding.
|
||||
//
|
||||
// The result is written into the codegen array, and the frequencies
|
||||
// of each code is written into the codegenFreq array.
|
||||
// Codes 0-15 are single byte codes. Codes 16-18 are followed by additional
|
||||
// information. Code badCode is an end marker
|
||||
//
|
||||
// numLiterals The number of literals in literalEncoding
|
||||
// numOffsets The number of offsets in offsetEncoding
|
||||
// litenc, offenc The literal and offset encoder to use
|
||||
func (w *huffmanBitWriter) generateCodegen(numLiterals int, numOffsets int, litEnc, offEnc *huffmanEncoder) {
|
||||
for i := range w.codegenFreq {
|
||||
w.codegenFreq[i] = 0
|
||||
}
|
||||
// Note that we are using codegen both as a temporary variable for holding
|
||||
// a copy of the frequencies, and as the place where we put the result.
|
||||
// This is fine because the output is always shorter than the input used
|
||||
// so far.
|
||||
codegen := w.codegen // cache
|
||||
// Copy the concatenated code sizes to codegen. Put a marker at the end.
|
||||
cgnl := codegen[:numLiterals]
|
||||
for i := range cgnl {
|
||||
cgnl[i] = uint8(litEnc.codes[i].len)
|
||||
}
|
||||
|
||||
cgnl = codegen[numLiterals : numLiterals+numOffsets]
|
||||
for i := range cgnl {
|
||||
cgnl[i] = uint8(offEnc.codes[i].len)
|
||||
}
|
||||
codegen[numLiterals+numOffsets] = badCode
|
||||
|
||||
size := codegen[0]
|
||||
count := 1
|
||||
outIndex := 0
|
||||
for inIndex := 1; size != badCode; inIndex++ {
|
||||
// INVARIANT: We have seen "count" copies of size that have not yet
|
||||
// had output generated for them.
|
||||
nextSize := codegen[inIndex]
|
||||
if nextSize == size {
|
||||
count++
|
||||
continue
|
||||
}
|
||||
// We need to generate codegen indicating "count" of size.
|
||||
if size != 0 {
|
||||
codegen[outIndex] = size
|
||||
outIndex++
|
||||
w.codegenFreq[size]++
|
||||
count--
|
||||
for count >= 3 {
|
||||
n := 6
|
||||
if n > count {
|
||||
n = count
|
||||
}
|
||||
codegen[outIndex] = 16
|
||||
outIndex++
|
||||
codegen[outIndex] = uint8(n - 3)
|
||||
outIndex++
|
||||
w.codegenFreq[16]++
|
||||
count -= n
|
||||
}
|
||||
} else {
|
||||
for count >= 11 {
|
||||
n := 138
|
||||
if n > count {
|
||||
n = count
|
||||
}
|
||||
codegen[outIndex] = 18
|
||||
outIndex++
|
||||
codegen[outIndex] = uint8(n - 11)
|
||||
outIndex++
|
||||
w.codegenFreq[18]++
|
||||
count -= n
|
||||
}
|
||||
if count >= 3 {
|
||||
// count >= 3 && count <= 10
|
||||
codegen[outIndex] = 17
|
||||
outIndex++
|
||||
codegen[outIndex] = uint8(count - 3)
|
||||
outIndex++
|
||||
w.codegenFreq[17]++
|
||||
count = 0
|
||||
}
|
||||
}
|
||||
count--
|
||||
for ; count >= 0; count-- {
|
||||
codegen[outIndex] = size
|
||||
outIndex++
|
||||
w.codegenFreq[size]++
|
||||
}
|
||||
// Set up invariant for next time through the loop.
|
||||
size = nextSize
|
||||
count = 1
|
||||
}
|
||||
// Marker indicating the end of the codegen.
|
||||
codegen[outIndex] = badCode
|
||||
}
|
||||
|
||||
// dynamicSize returns the size of dynamically encoded data in bits.
|
||||
func (w *huffmanBitWriter) dynamicSize(litEnc, offEnc *huffmanEncoder, extraBits int) (size, numCodegens int) {
|
||||
numCodegens = len(w.codegenFreq)
|
||||
for numCodegens > 4 && w.codegenFreq[codegenOrder[numCodegens-1]] == 0 {
|
||||
numCodegens--
|
||||
}
|
||||
header := 3 + 5 + 5 + 4 + (3 * numCodegens) +
|
||||
w.codegenEncoding.bitLength(w.codegenFreq[:]) +
|
||||
int(w.codegenFreq[16])*2 +
|
||||
int(w.codegenFreq[17])*3 +
|
||||
int(w.codegenFreq[18])*7
|
||||
size = header +
|
||||
litEnc.bitLength(w.literalFreq) +
|
||||
offEnc.bitLength(w.offsetFreq) +
|
||||
extraBits
|
||||
|
||||
return size, numCodegens
|
||||
}
|
||||
|
||||
// fixedSize returns the size of dynamically encoded data in bits.
|
||||
func (w *huffmanBitWriter) fixedSize(extraBits int) int {
|
||||
return 3 +
|
||||
fixedLiteralEncoding.bitLength(w.literalFreq) +
|
||||
fixedOffsetEncoding.bitLength(w.offsetFreq) +
|
||||
extraBits
|
||||
}
|
||||
|
||||
// storedSize calculates the stored size, including header.
|
||||
// The function returns the size in bits and whether the block
|
||||
// fits inside a single block.
|
||||
func (w *huffmanBitWriter) storedSize(in []byte) (int, bool) {
|
||||
if in == nil {
|
||||
return 0, false
|
||||
}
|
||||
if len(in) <= maxStoreBlockSize {
|
||||
return (len(in) + 5) * 8, true
|
||||
}
|
||||
return 0, false
|
||||
}
|
||||
|
||||
func (w *huffmanBitWriter) writeCode(c hcode) {
|
||||
if w.err != nil {
|
||||
return
|
||||
}
|
||||
w.bits |= uint64(c.code) << w.nbits
|
||||
w.nbits += uint(c.len)
|
||||
if w.nbits >= 48 {
|
||||
bits := w.bits
|
||||
w.bits >>= 48
|
||||
w.nbits -= 48
|
||||
n := w.nbytes
|
||||
bytes := w.bytes[n : n+6]
|
||||
bytes[0] = byte(bits)
|
||||
bytes[1] = byte(bits >> 8)
|
||||
bytes[2] = byte(bits >> 16)
|
||||
bytes[3] = byte(bits >> 24)
|
||||
bytes[4] = byte(bits >> 32)
|
||||
bytes[5] = byte(bits >> 40)
|
||||
n += 6
|
||||
if n >= bufferFlushSize {
|
||||
w.write(w.bytes[:n])
|
||||
n = 0
|
||||
}
|
||||
w.nbytes = n
|
||||
}
|
||||
}
|
||||
|
||||
// Write the header of a dynamic Huffman block to the output stream.
|
||||
//
|
||||
// numLiterals The number of literals specified in codegen
|
||||
// numOffsets The number of offsets specified in codegen
|
||||
// numCodegens The number of codegens used in codegen
|
||||
func (w *huffmanBitWriter) writeDynamicHeader(numLiterals int, numOffsets int, numCodegens int, isEof bool) {
|
||||
if w.err != nil {
|
||||
return
|
||||
}
|
||||
var firstBits int32 = 4
|
||||
if isEof {
|
||||
firstBits = 5
|
||||
}
|
||||
w.writeBits(firstBits, 3)
|
||||
w.writeBits(int32(numLiterals-257), 5)
|
||||
w.writeBits(int32(numOffsets-1), 5)
|
||||
w.writeBits(int32(numCodegens-4), 4)
|
||||
|
||||
for i := 0; i < numCodegens; i++ {
|
||||
value := uint(w.codegenEncoding.codes[codegenOrder[i]].len)
|
||||
w.writeBits(int32(value), 3)
|
||||
}
|
||||
|
||||
i := 0
|
||||
for {
|
||||
var codeWord int = int(w.codegen[i])
|
||||
i++
|
||||
if codeWord == badCode {
|
||||
break
|
||||
}
|
||||
w.writeCode(w.codegenEncoding.codes[uint32(codeWord)])
|
||||
|
||||
switch codeWord {
|
||||
case 16:
|
||||
w.writeBits(int32(w.codegen[i]), 2)
|
||||
i++
|
||||
break
|
||||
case 17:
|
||||
w.writeBits(int32(w.codegen[i]), 3)
|
||||
i++
|
||||
break
|
||||
case 18:
|
||||
w.writeBits(int32(w.codegen[i]), 7)
|
||||
i++
|
||||
break
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func (w *huffmanBitWriter) writeStoredHeader(length int, isEof bool) {
|
||||
if w.err != nil {
|
||||
return
|
||||
}
|
||||
var flag int32
|
||||
if isEof {
|
||||
flag = 1
|
||||
}
|
||||
w.writeBits(flag, 3)
|
||||
w.flush()
|
||||
w.writeBits(int32(length), 16)
|
||||
w.writeBits(int32(^uint16(length)), 16)
|
||||
}
|
||||
|
||||
func (w *huffmanBitWriter) writeFixedHeader(isEof bool) {
|
||||
if w.err != nil {
|
||||
return
|
||||
}
|
||||
// Indicate that we are a fixed Huffman block
|
||||
var value int32 = 2
|
||||
if isEof {
|
||||
value = 3
|
||||
}
|
||||
w.writeBits(value, 3)
|
||||
}
|
||||
|
||||
// writeBlock will write a block of tokens with the smallest encoding.
|
||||
// The original input can be supplied, and if the huffman encoded data
|
||||
// is larger than the original bytes, the data will be written as a
|
||||
// stored block.
|
||||
// If the input is nil, the tokens will always be Huffman encoded.
|
||||
func (w *huffmanBitWriter) writeBlock(tokens []token, eof bool, input []byte) {
|
||||
if w.err != nil {
|
||||
return
|
||||
}
|
||||
|
||||
tokens = append(tokens, endBlockMarker)
|
||||
numLiterals, numOffsets := w.indexTokens(tokens)
|
||||
|
||||
var extraBits int
|
||||
storedSize, storable := w.storedSize(input)
|
||||
if storable {
|
||||
// We only bother calculating the costs of the extra bits required by
|
||||
// the length of offset fields (which will be the same for both fixed
|
||||
// and dynamic encoding), if we need to compare those two encodings
|
||||
// against stored encoding.
|
||||
for lengthCode := lengthCodesStart + 8; lengthCode < numLiterals; lengthCode++ {
|
||||
// First eight length codes have extra size = 0.
|
||||
extraBits += int(w.literalFreq[lengthCode]) * int(lengthExtraBits[lengthCode-lengthCodesStart])
|
||||
}
|
||||
for offsetCode := 4; offsetCode < numOffsets; offsetCode++ {
|
||||
// First four offset codes have extra size = 0.
|
||||
extraBits += int(w.offsetFreq[offsetCode]) * int(offsetExtraBits[offsetCode])
|
||||
}
|
||||
}
|
||||
|
||||
// Figure out smallest code.
|
||||
// Fixed Huffman baseline.
|
||||
var literalEncoding = fixedLiteralEncoding
|
||||
var offsetEncoding = fixedOffsetEncoding
|
||||
var size = w.fixedSize(extraBits)
|
||||
|
||||
// Dynamic Huffman?
|
||||
var numCodegens int
|
||||
|
||||
// Generate codegen and codegenFrequencies, which indicates how to encode
|
||||
// the literalEncoding and the offsetEncoding.
|
||||
w.generateCodegen(numLiterals, numOffsets, w.literalEncoding, w.offsetEncoding)
|
||||
w.codegenEncoding.generate(w.codegenFreq[:], 7)
|
||||
dynamicSize, numCodegens := w.dynamicSize(w.literalEncoding, w.offsetEncoding, extraBits)
|
||||
|
||||
if dynamicSize < size {
|
||||
size = dynamicSize
|
||||
literalEncoding = w.literalEncoding
|
||||
offsetEncoding = w.offsetEncoding
|
||||
}
|
||||
|
||||
// Stored bytes?
|
||||
if storable && storedSize < size {
|
||||
w.writeStoredHeader(len(input), eof)
|
||||
w.writeBytes(input)
|
||||
return
|
||||
}
|
||||
|
||||
// Huffman.
|
||||
if literalEncoding == fixedLiteralEncoding {
|
||||
w.writeFixedHeader(eof)
|
||||
} else {
|
||||
w.writeDynamicHeader(numLiterals, numOffsets, numCodegens, eof)
|
||||
}
|
||||
|
||||
// Write the tokens.
|
||||
w.writeTokens(tokens, literalEncoding.codes, offsetEncoding.codes)
|
||||
}
|
||||
|
||||
// writeBlockDynamic encodes a block using a dynamic Huffman table.
|
||||
// This should be used if the symbols used have a disproportionate
|
||||
// histogram distribution.
|
||||
// If input is supplied and the compression savings are below 1/16th of the
|
||||
// input size the block is stored.
|
||||
func (w *huffmanBitWriter) writeBlockDynamic(tokens []token, eof bool, input []byte) {
|
||||
if w.err != nil {
|
||||
return
|
||||
}
|
||||
|
||||
tokens = append(tokens, endBlockMarker)
|
||||
numLiterals, numOffsets := w.indexTokens(tokens)
|
||||
|
||||
// Generate codegen and codegenFrequencies, which indicates how to encode
|
||||
// the literalEncoding and the offsetEncoding.
|
||||
w.generateCodegen(numLiterals, numOffsets, w.literalEncoding, w.offsetEncoding)
|
||||
w.codegenEncoding.generate(w.codegenFreq[:], 7)
|
||||
size, numCodegens := w.dynamicSize(w.literalEncoding, w.offsetEncoding, 0)
|
||||
|
||||
// Store bytes, if we don't get a reasonable improvement.
|
||||
if ssize, storable := w.storedSize(input); storable && ssize < (size+size>>4) {
|
||||
w.writeStoredHeader(len(input), eof)
|
||||
w.writeBytes(input)
|
||||
return
|
||||
}
|
||||
|
||||
// Write Huffman table.
|
||||
w.writeDynamicHeader(numLiterals, numOffsets, numCodegens, eof)
|
||||
|
||||
// Write the tokens.
|
||||
w.writeTokens(tokens, w.literalEncoding.codes, w.offsetEncoding.codes)
|
||||
}
|
||||
|
||||
// indexTokens indexes a slice of tokens, and updates
|
||||
// literalFreq and offsetFreq, and generates literalEncoding
|
||||
// and offsetEncoding.
|
||||
// The number of literal and offset tokens is returned.
|
||||
func (w *huffmanBitWriter) indexTokens(tokens []token) (numLiterals, numOffsets int) {
|
||||
for i := range w.literalFreq {
|
||||
w.literalFreq[i] = 0
|
||||
}
|
||||
for i := range w.offsetFreq {
|
||||
w.offsetFreq[i] = 0
|
||||
}
|
||||
|
||||
for _, t := range tokens {
|
||||
if t < matchType {
|
||||
w.literalFreq[t.literal()]++
|
||||
continue
|
||||
}
|
||||
length := t.length()
|
||||
offset := t.offset()
|
||||
w.literalFreq[lengthCodesStart+lengthCode(length)]++
|
||||
w.offsetFreq[offsetCode(offset)]++
|
||||
}
|
||||
|
||||
// get the number of literals
|
||||
numLiterals = len(w.literalFreq)
|
||||
for w.literalFreq[numLiterals-1] == 0 {
|
||||
numLiterals--
|
||||
}
|
||||
// get the number of offsets
|
||||
numOffsets = len(w.offsetFreq)
|
||||
for numOffsets > 0 && w.offsetFreq[numOffsets-1] == 0 {
|
||||
numOffsets--
|
||||
}
|
||||
if numOffsets == 0 {
|
||||
// We haven't found a single match. If we want to go with the dynamic encoding,
|
||||
// we should count at least one offset to be sure that the offset huffman tree could be encoded.
|
||||
w.offsetFreq[0] = 1
|
||||
numOffsets = 1
|
||||
}
|
||||
w.literalEncoding.generate(w.literalFreq, 15)
|
||||
w.offsetEncoding.generate(w.offsetFreq, 15)
|
||||
return
|
||||
}
|
||||
|
||||
// writeTokens writes a slice of tokens to the output.
|
||||
// codes for literal and offset encoding must be supplied.
|
||||
func (w *huffmanBitWriter) writeTokens(tokens []token, leCodes, oeCodes []hcode) {
|
||||
if w.err != nil {
|
||||
return
|
||||
}
|
||||
for _, t := range tokens {
|
||||
if t < matchType {
|
||||
w.writeCode(leCodes[t.literal()])
|
||||
continue
|
||||
}
|
||||
// Write the length
|
||||
length := t.length()
|
||||
lengthCode := lengthCode(length)
|
||||
w.writeCode(leCodes[lengthCode+lengthCodesStart])
|
||||
extraLengthBits := uint(lengthExtraBits[lengthCode])
|
||||
if extraLengthBits > 0 {
|
||||
extraLength := int32(length - lengthBase[lengthCode])
|
||||
w.writeBits(extraLength, extraLengthBits)
|
||||
}
|
||||
// Write the offset
|
||||
offset := t.offset()
|
||||
offsetCode := offsetCode(offset)
|
||||
w.writeCode(oeCodes[offsetCode])
|
||||
extraOffsetBits := uint(offsetExtraBits[offsetCode])
|
||||
if extraOffsetBits > 0 {
|
||||
extraOffset := int32(offset - offsetBase[offsetCode])
|
||||
w.writeBits(extraOffset, extraOffsetBits)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// huffOffset is a static offset encoder used for huffman only encoding.
|
||||
// It can be reused since we will not be encoding offset values.
|
||||
var huffOffset *huffmanEncoder
|
||||
|
||||
func init() {
|
||||
w := newHuffmanBitWriter(nil)
|
||||
w.offsetFreq[0] = 1
|
||||
huffOffset = newHuffmanEncoder(offsetCodeCount)
|
||||
huffOffset.generate(w.offsetFreq, 15)
|
||||
}
|
||||
|
||||
// writeBlockHuff encodes a block of bytes as either
|
||||
// Huffman encoded literals or uncompressed bytes if the
|
||||
// results only gains very little from compression.
|
||||
func (w *huffmanBitWriter) writeBlockHuff(eof bool, input []byte) {
|
||||
if w.err != nil {
|
||||
return
|
||||
}
|
||||
|
||||
// Clear histogram
|
||||
for i := range w.literalFreq {
|
||||
w.literalFreq[i] = 0
|
||||
}
|
||||
|
||||
// Add everything as literals
|
||||
histogram(input, w.literalFreq)
|
||||
|
||||
w.literalFreq[endBlockMarker] = 1
|
||||
|
||||
const numLiterals = endBlockMarker + 1
|
||||
const numOffsets = 1
|
||||
|
||||
w.literalEncoding.generate(w.literalFreq, 15)
|
||||
|
||||
// Figure out smallest code.
|
||||
// Always use dynamic Huffman or Store
|
||||
var numCodegens int
|
||||
|
||||
// Generate codegen and codegenFrequencies, which indicates how to encode
|
||||
// the literalEncoding and the offsetEncoding.
|
||||
w.generateCodegen(numLiterals, numOffsets, w.literalEncoding, huffOffset)
|
||||
w.codegenEncoding.generate(w.codegenFreq[:], 7)
|
||||
size, numCodegens := w.dynamicSize(w.literalEncoding, huffOffset, 0)
|
||||
|
||||
// Store bytes, if we don't get a reasonable improvement.
|
||||
if ssize, storable := w.storedSize(input); storable && ssize < (size+size>>4) {
|
||||
w.writeStoredHeader(len(input), eof)
|
||||
w.writeBytes(input)
|
||||
return
|
||||
}
|
||||
|
||||
// Huffman.
|
||||
w.writeDynamicHeader(numLiterals, numOffsets, numCodegens, eof)
|
||||
encoding := w.literalEncoding.codes[:257]
|
||||
n := w.nbytes
|
||||
for _, t := range input {
|
||||
// Bitwriting inlined, ~30% speedup
|
||||
c := encoding[t]
|
||||
w.bits |= uint64(c.code) << w.nbits
|
||||
w.nbits += uint(c.len)
|
||||
if w.nbits < 48 {
|
||||
continue
|
||||
}
|
||||
// Store 6 bytes
|
||||
bits := w.bits
|
||||
w.bits >>= 48
|
||||
w.nbits -= 48
|
||||
bytes := w.bytes[n : n+6]
|
||||
bytes[0] = byte(bits)
|
||||
bytes[1] = byte(bits >> 8)
|
||||
bytes[2] = byte(bits >> 16)
|
||||
bytes[3] = byte(bits >> 24)
|
||||
bytes[4] = byte(bits >> 32)
|
||||
bytes[5] = byte(bits >> 40)
|
||||
n += 6
|
||||
if n < bufferFlushSize {
|
||||
continue
|
||||
}
|
||||
w.write(w.bytes[:n])
|
||||
if w.err != nil {
|
||||
return // Return early in the event of write failures
|
||||
}
|
||||
n = 0
|
||||
}
|
||||
w.nbytes = n
|
||||
w.writeCode(encoding[endBlockMarker])
|
||||
}
|
366
vendor/github.com/klauspost/compress/flate/huffman_bit_writer_test.go
generated
vendored
Normal file
366
vendor/github.com/klauspost/compress/flate/huffman_bit_writer_test.go
generated
vendored
Normal file
File diff suppressed because one or more lines are too long
344
vendor/github.com/klauspost/compress/flate/huffman_code.go
generated
vendored
Normal file
344
vendor/github.com/klauspost/compress/flate/huffman_code.go
generated
vendored
Normal file
@@ -0,0 +1,344 @@
|
||||
// Copyright 2009 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package flate
|
||||
|
||||
import (
|
||||
"math"
|
||||
"sort"
|
||||
)
|
||||
|
||||
// hcode is a huffman code with a bit code and bit length.
|
||||
type hcode struct {
|
||||
code, len uint16
|
||||
}
|
||||
|
||||
type huffmanEncoder struct {
|
||||
codes []hcode
|
||||
freqcache []literalNode
|
||||
bitCount [17]int32
|
||||
lns byLiteral // stored to avoid repeated allocation in generate
|
||||
lfs byFreq // stored to avoid repeated allocation in generate
|
||||
}
|
||||
|
||||
type literalNode struct {
|
||||
literal uint16
|
||||
freq int32
|
||||
}
|
||||
|
||||
// A levelInfo describes the state of the constructed tree for a given depth.
|
||||
type levelInfo struct {
|
||||
// Our level. for better printing
|
||||
level int32
|
||||
|
||||
// The frequency of the last node at this level
|
||||
lastFreq int32
|
||||
|
||||
// The frequency of the next character to add to this level
|
||||
nextCharFreq int32
|
||||
|
||||
// The frequency of the next pair (from level below) to add to this level.
|
||||
// Only valid if the "needed" value of the next lower level is 0.
|
||||
nextPairFreq int32
|
||||
|
||||
// The number of chains remaining to generate for this level before moving
|
||||
// up to the next level
|
||||
needed int32
|
||||
}
|
||||
|
||||
// set sets the code and length of an hcode.
|
||||
func (h *hcode) set(code uint16, length uint16) {
|
||||
h.len = length
|
||||
h.code = code
|
||||
}
|
||||
|
||||
func maxNode() literalNode { return literalNode{math.MaxUint16, math.MaxInt32} }
|
||||
|
||||
func newHuffmanEncoder(size int) *huffmanEncoder {
|
||||
return &huffmanEncoder{codes: make([]hcode, size)}
|
||||
}
|
||||
|
||||
// Generates a HuffmanCode corresponding to the fixed literal table
|
||||
func generateFixedLiteralEncoding() *huffmanEncoder {
|
||||
h := newHuffmanEncoder(maxNumLit)
|
||||
codes := h.codes
|
||||
var ch uint16
|
||||
for ch = 0; ch < maxNumLit; ch++ {
|
||||
var bits uint16
|
||||
var size uint16
|
||||
switch {
|
||||
case ch < 144:
|
||||
// size 8, 000110000 .. 10111111
|
||||
bits = ch + 48
|
||||
size = 8
|
||||
break
|
||||
case ch < 256:
|
||||
// size 9, 110010000 .. 111111111
|
||||
bits = ch + 400 - 144
|
||||
size = 9
|
||||
break
|
||||
case ch < 280:
|
||||
// size 7, 0000000 .. 0010111
|
||||
bits = ch - 256
|
||||
size = 7
|
||||
break
|
||||
default:
|
||||
// size 8, 11000000 .. 11000111
|
||||
bits = ch + 192 - 280
|
||||
size = 8
|
||||
}
|
||||
codes[ch] = hcode{code: reverseBits(bits, byte(size)), len: size}
|
||||
}
|
||||
return h
|
||||
}
|
||||
|
||||
func generateFixedOffsetEncoding() *huffmanEncoder {
|
||||
h := newHuffmanEncoder(30)
|
||||
codes := h.codes
|
||||
for ch := range codes {
|
||||
codes[ch] = hcode{code: reverseBits(uint16(ch), 5), len: 5}
|
||||
}
|
||||
return h
|
||||
}
|
||||
|
||||
var fixedLiteralEncoding *huffmanEncoder = generateFixedLiteralEncoding()
|
||||
var fixedOffsetEncoding *huffmanEncoder = generateFixedOffsetEncoding()
|
||||
|
||||
func (h *huffmanEncoder) bitLength(freq []int32) int {
|
||||
var total int
|
||||
for i, f := range freq {
|
||||
if f != 0 {
|
||||
total += int(f) * int(h.codes[i].len)
|
||||
}
|
||||
}
|
||||
return total
|
||||
}
|
||||
|
||||
const maxBitsLimit = 16
|
||||
|
||||
// Return the number of literals assigned to each bit size in the Huffman encoding
|
||||
//
|
||||
// This method is only called when list.length >= 3
|
||||
// The cases of 0, 1, and 2 literals are handled by special case code.
|
||||
//
|
||||
// list An array of the literals with non-zero frequencies
|
||||
// and their associated frequencies. The array is in order of increasing
|
||||
// frequency, and has as its last element a special element with frequency
|
||||
// MaxInt32
|
||||
// maxBits The maximum number of bits that should be used to encode any literal.
|
||||
// Must be less than 16.
|
||||
// return An integer array in which array[i] indicates the number of literals
|
||||
// that should be encoded in i bits.
|
||||
func (h *huffmanEncoder) bitCounts(list []literalNode, maxBits int32) []int32 {
|
||||
if maxBits >= maxBitsLimit {
|
||||
panic("flate: maxBits too large")
|
||||
}
|
||||
n := int32(len(list))
|
||||
list = list[0 : n+1]
|
||||
list[n] = maxNode()
|
||||
|
||||
// The tree can't have greater depth than n - 1, no matter what. This
|
||||
// saves a little bit of work in some small cases
|
||||
if maxBits > n-1 {
|
||||
maxBits = n - 1
|
||||
}
|
||||
|
||||
// Create information about each of the levels.
|
||||
// A bogus "Level 0" whose sole purpose is so that
|
||||
// level1.prev.needed==0. This makes level1.nextPairFreq
|
||||
// be a legitimate value that never gets chosen.
|
||||
var levels [maxBitsLimit]levelInfo
|
||||
// leafCounts[i] counts the number of literals at the left
|
||||
// of ancestors of the rightmost node at level i.
|
||||
// leafCounts[i][j] is the number of literals at the left
|
||||
// of the level j ancestor.
|
||||
var leafCounts [maxBitsLimit][maxBitsLimit]int32
|
||||
|
||||
for level := int32(1); level <= maxBits; level++ {
|
||||
// For every level, the first two items are the first two characters.
|
||||
// We initialize the levels as if we had already figured this out.
|
||||
levels[level] = levelInfo{
|
||||
level: level,
|
||||
lastFreq: list[1].freq,
|
||||
nextCharFreq: list[2].freq,
|
||||
nextPairFreq: list[0].freq + list[1].freq,
|
||||
}
|
||||
leafCounts[level][level] = 2
|
||||
if level == 1 {
|
||||
levels[level].nextPairFreq = math.MaxInt32
|
||||
}
|
||||
}
|
||||
|
||||
// We need a total of 2*n - 2 items at top level and have already generated 2.
|
||||
levels[maxBits].needed = 2*n - 4
|
||||
|
||||
level := maxBits
|
||||
for {
|
||||
l := &levels[level]
|
||||
if l.nextPairFreq == math.MaxInt32 && l.nextCharFreq == math.MaxInt32 {
|
||||
// We've run out of both leafs and pairs.
|
||||
// End all calculations for this level.
|
||||
// To make sure we never come back to this level or any lower level,
|
||||
// set nextPairFreq impossibly large.
|
||||
l.needed = 0
|
||||
levels[level+1].nextPairFreq = math.MaxInt32
|
||||
level++
|
||||
continue
|
||||
}
|
||||
|
||||
prevFreq := l.lastFreq
|
||||
if l.nextCharFreq < l.nextPairFreq {
|
||||
// The next item on this row is a leaf node.
|
||||
n := leafCounts[level][level] + 1
|
||||
l.lastFreq = l.nextCharFreq
|
||||
// Lower leafCounts are the same of the previous node.
|
||||
leafCounts[level][level] = n
|
||||
l.nextCharFreq = list[n].freq
|
||||
} else {
|
||||
// The next item on this row is a pair from the previous row.
|
||||
// nextPairFreq isn't valid until we generate two
|
||||
// more values in the level below
|
||||
l.lastFreq = l.nextPairFreq
|
||||
// Take leaf counts from the lower level, except counts[level] remains the same.
|
||||
copy(leafCounts[level][:level], leafCounts[level-1][:level])
|
||||
levels[l.level-1].needed = 2
|
||||
}
|
||||
|
||||
if l.needed--; l.needed == 0 {
|
||||
// We've done everything we need to do for this level.
|
||||
// Continue calculating one level up. Fill in nextPairFreq
|
||||
// of that level with the sum of the two nodes we've just calculated on
|
||||
// this level.
|
||||
if l.level == maxBits {
|
||||
// All done!
|
||||
break
|
||||
}
|
||||
levels[l.level+1].nextPairFreq = prevFreq + l.lastFreq
|
||||
level++
|
||||
} else {
|
||||
// If we stole from below, move down temporarily to replenish it.
|
||||
for levels[level-1].needed > 0 {
|
||||
level--
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Somethings is wrong if at the end, the top level is null or hasn't used
|
||||
// all of the leaves.
|
||||
if leafCounts[maxBits][maxBits] != n {
|
||||
panic("leafCounts[maxBits][maxBits] != n")
|
||||
}
|
||||
|
||||
bitCount := h.bitCount[:maxBits+1]
|
||||
bits := 1
|
||||
counts := &leafCounts[maxBits]
|
||||
for level := maxBits; level > 0; level-- {
|
||||
// chain.leafCount gives the number of literals requiring at least "bits"
|
||||
// bits to encode.
|
||||
bitCount[bits] = counts[level] - counts[level-1]
|
||||
bits++
|
||||
}
|
||||
return bitCount
|
||||
}
|
||||
|
||||
// Look at the leaves and assign them a bit count and an encoding as specified
|
||||
// in RFC 1951 3.2.2
|
||||
func (h *huffmanEncoder) assignEncodingAndSize(bitCount []int32, list []literalNode) {
|
||||
code := uint16(0)
|
||||
for n, bits := range bitCount {
|
||||
code <<= 1
|
||||
if n == 0 || bits == 0 {
|
||||
continue
|
||||
}
|
||||
// The literals list[len(list)-bits] .. list[len(list)-bits]
|
||||
// are encoded using "bits" bits, and get the values
|
||||
// code, code + 1, .... The code values are
|
||||
// assigned in literal order (not frequency order).
|
||||
chunk := list[len(list)-int(bits):]
|
||||
|
||||
h.lns.sort(chunk)
|
||||
for _, node := range chunk {
|
||||
h.codes[node.literal] = hcode{code: reverseBits(code, uint8(n)), len: uint16(n)}
|
||||
code++
|
||||
}
|
||||
list = list[0 : len(list)-int(bits)]
|
||||
}
|
||||
}
|
||||
|
||||
// Update this Huffman Code object to be the minimum code for the specified frequency count.
|
||||
//
|
||||
// freq An array of frequencies, in which frequency[i] gives the frequency of literal i.
|
||||
// maxBits The maximum number of bits to use for any literal.
|
||||
func (h *huffmanEncoder) generate(freq []int32, maxBits int32) {
|
||||
if h.freqcache == nil {
|
||||
// Allocate a reusable buffer with the longest possible frequency table.
|
||||
// Possible lengths are codegenCodeCount, offsetCodeCount and maxNumLit.
|
||||
// The largest of these is maxNumLit, so we allocate for that case.
|
||||
h.freqcache = make([]literalNode, maxNumLit+1)
|
||||
}
|
||||
list := h.freqcache[:len(freq)+1]
|
||||
// Number of non-zero literals
|
||||
count := 0
|
||||
// Set list to be the set of all non-zero literals and their frequencies
|
||||
for i, f := range freq {
|
||||
if f != 0 {
|
||||
list[count] = literalNode{uint16(i), f}
|
||||
count++
|
||||
} else {
|
||||
list[count] = literalNode{}
|
||||
h.codes[i].len = 0
|
||||
}
|
||||
}
|
||||
list[len(freq)] = literalNode{}
|
||||
|
||||
list = list[:count]
|
||||
if count <= 2 {
|
||||
// Handle the small cases here, because they are awkward for the general case code. With
|
||||
// two or fewer literals, everything has bit length 1.
|
||||
for i, node := range list {
|
||||
// "list" is in order of increasing literal value.
|
||||
h.codes[node.literal].set(uint16(i), 1)
|
||||
}
|
||||
return
|
||||
}
|
||||
h.lfs.sort(list)
|
||||
|
||||
// Get the number of literals for each bit count
|
||||
bitCount := h.bitCounts(list, maxBits)
|
||||
// And do the assignment
|
||||
h.assignEncodingAndSize(bitCount, list)
|
||||
}
|
||||
|
||||
type byLiteral []literalNode
|
||||
|
||||
func (s *byLiteral) sort(a []literalNode) {
|
||||
*s = byLiteral(a)
|
||||
sort.Sort(s)
|
||||
}
|
||||
|
||||
func (s byLiteral) Len() int { return len(s) }
|
||||
|
||||
func (s byLiteral) Less(i, j int) bool {
|
||||
return s[i].literal < s[j].literal
|
||||
}
|
||||
|
||||
func (s byLiteral) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
|
||||
|
||||
type byFreq []literalNode
|
||||
|
||||
func (s *byFreq) sort(a []literalNode) {
|
||||
*s = byFreq(a)
|
||||
sort.Sort(s)
|
||||
}
|
||||
|
||||
func (s byFreq) Len() int { return len(s) }
|
||||
|
||||
func (s byFreq) Less(i, j int) bool {
|
||||
if s[i].freq == s[j].freq {
|
||||
return s[i].literal < s[j].literal
|
||||
}
|
||||
return s[i].freq < s[j].freq
|
||||
}
|
||||
|
||||
func (s byFreq) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
|
846
vendor/github.com/klauspost/compress/flate/inflate.go
generated
vendored
Normal file
846
vendor/github.com/klauspost/compress/flate/inflate.go
generated
vendored
Normal file
@@ -0,0 +1,846 @@
|
||||
// Copyright 2009 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
// Package flate implements the DEFLATE compressed data format, described in
|
||||
// RFC 1951. The gzip and zlib packages implement access to DEFLATE-based file
|
||||
// formats.
|
||||
package flate
|
||||
|
||||
import (
|
||||
"bufio"
|
||||
"io"
|
||||
"strconv"
|
||||
"sync"
|
||||
)
|
||||
|
||||
const (
|
||||
maxCodeLen = 16 // max length of Huffman code
|
||||
// The next three numbers come from the RFC section 3.2.7, with the
|
||||
// additional proviso in section 3.2.5 which implies that distance codes
|
||||
// 30 and 31 should never occur in compressed data.
|
||||
maxNumLit = 286
|
||||
maxNumDist = 30
|
||||
numCodes = 19 // number of codes in Huffman meta-code
|
||||
)
|
||||
|
||||
// Initialize the fixedHuffmanDecoder only once upon first use.
|
||||
var fixedOnce sync.Once
|
||||
var fixedHuffmanDecoder huffmanDecoder
|
||||
|
||||
// A CorruptInputError reports the presence of corrupt input at a given offset.
|
||||
type CorruptInputError int64
|
||||
|
||||
func (e CorruptInputError) Error() string {
|
||||
return "flate: corrupt input before offset " + strconv.FormatInt(int64(e), 10)
|
||||
}
|
||||
|
||||
// An InternalError reports an error in the flate code itself.
|
||||
type InternalError string
|
||||
|
||||
func (e InternalError) Error() string { return "flate: internal error: " + string(e) }
|
||||
|
||||
// A ReadError reports an error encountered while reading input.
|
||||
//
|
||||
// Deprecated: No longer returned.
|
||||
type ReadError struct {
|
||||
Offset int64 // byte offset where error occurred
|
||||
Err error // error returned by underlying Read
|
||||
}
|
||||
|
||||
func (e *ReadError) Error() string {
|
||||
return "flate: read error at offset " + strconv.FormatInt(e.Offset, 10) + ": " + e.Err.Error()
|
||||
}
|
||||
|
||||
// A WriteError reports an error encountered while writing output.
|
||||
//
|
||||
// Deprecated: No longer returned.
|
||||
type WriteError struct {
|
||||
Offset int64 // byte offset where error occurred
|
||||
Err error // error returned by underlying Write
|
||||
}
|
||||
|
||||
func (e *WriteError) Error() string {
|
||||
return "flate: write error at offset " + strconv.FormatInt(e.Offset, 10) + ": " + e.Err.Error()
|
||||
}
|
||||
|
||||
// Resetter resets a ReadCloser returned by NewReader or NewReaderDict to
|
||||
// to switch to a new underlying Reader. This permits reusing a ReadCloser
|
||||
// instead of allocating a new one.
|
||||
type Resetter interface {
|
||||
// Reset discards any buffered data and resets the Resetter as if it was
|
||||
// newly initialized with the given reader.
|
||||
Reset(r io.Reader, dict []byte) error
|
||||
}
|
||||
|
||||
// The data structure for decoding Huffman tables is based on that of
|
||||
// zlib. There is a lookup table of a fixed bit width (huffmanChunkBits),
|
||||
// For codes smaller than the table width, there are multiple entries
|
||||
// (each combination of trailing bits has the same value). For codes
|
||||
// larger than the table width, the table contains a link to an overflow
|
||||
// table. The width of each entry in the link table is the maximum code
|
||||
// size minus the chunk width.
|
||||
//
|
||||
// Note that you can do a lookup in the table even without all bits
|
||||
// filled. Since the extra bits are zero, and the DEFLATE Huffman codes
|
||||
// have the property that shorter codes come before longer ones, the
|
||||
// bit length estimate in the result is a lower bound on the actual
|
||||
// number of bits.
|
||||
//
|
||||
// See the following:
|
||||
// http://www.gzip.org/algorithm.txt
|
||||
|
||||
// chunk & 15 is number of bits
|
||||
// chunk >> 4 is value, including table link
|
||||
|
||||
const (
|
||||
huffmanChunkBits = 9
|
||||
huffmanNumChunks = 1 << huffmanChunkBits
|
||||
huffmanCountMask = 15
|
||||
huffmanValueShift = 4
|
||||
)
|
||||
|
||||
type huffmanDecoder struct {
|
||||
min int // the minimum code length
|
||||
chunks [huffmanNumChunks]uint32 // chunks as described above
|
||||
links [][]uint32 // overflow links
|
||||
linkMask uint32 // mask the width of the link table
|
||||
}
|
||||
|
||||
// Initialize Huffman decoding tables from array of code lengths.
|
||||
// Following this function, h is guaranteed to be initialized into a complete
|
||||
// tree (i.e., neither over-subscribed nor under-subscribed). The exception is a
|
||||
// degenerate case where the tree has only a single symbol with length 1. Empty
|
||||
// trees are permitted.
|
||||
func (h *huffmanDecoder) init(bits []int) bool {
|
||||
// Sanity enables additional runtime tests during Huffman
|
||||
// table construction. It's intended to be used during
|
||||
// development to supplement the currently ad-hoc unit tests.
|
||||
const sanity = false
|
||||
|
||||
if h.min != 0 {
|
||||
*h = huffmanDecoder{}
|
||||
}
|
||||
|
||||
// Count number of codes of each length,
|
||||
// compute min and max length.
|
||||
var count [maxCodeLen]int
|
||||
var min, max int
|
||||
for _, n := range bits {
|
||||
if n == 0 {
|
||||
continue
|
||||
}
|
||||
if min == 0 || n < min {
|
||||
min = n
|
||||
}
|
||||
if n > max {
|
||||
max = n
|
||||
}
|
||||
count[n]++
|
||||
}
|
||||
|
||||
// Empty tree. The decompressor.huffSym function will fail later if the tree
|
||||
// is used. Technically, an empty tree is only valid for the HDIST tree and
|
||||
// not the HCLEN and HLIT tree. However, a stream with an empty HCLEN tree
|
||||
// is guaranteed to fail since it will attempt to use the tree to decode the
|
||||
// codes for the HLIT and HDIST trees. Similarly, an empty HLIT tree is
|
||||
// guaranteed to fail later since the compressed data section must be
|
||||
// composed of at least one symbol (the end-of-block marker).
|
||||
if max == 0 {
|
||||
return true
|
||||
}
|
||||
|
||||
code := 0
|
||||
var nextcode [maxCodeLen]int
|
||||
for i := min; i <= max; i++ {
|
||||
code <<= 1
|
||||
nextcode[i] = code
|
||||
code += count[i]
|
||||
}
|
||||
|
||||
// Check that the coding is complete (i.e., that we've
|
||||
// assigned all 2-to-the-max possible bit sequences).
|
||||
// Exception: To be compatible with zlib, we also need to
|
||||
// accept degenerate single-code codings. See also
|
||||
// TestDegenerateHuffmanCoding.
|
||||
if code != 1<<uint(max) && !(code == 1 && max == 1) {
|
||||
return false
|
||||
}
|
||||
|
||||
h.min = min
|
||||
if max > huffmanChunkBits {
|
||||
numLinks := 1 << (uint(max) - huffmanChunkBits)
|
||||
h.linkMask = uint32(numLinks - 1)
|
||||
|
||||
// create link tables
|
||||
link := nextcode[huffmanChunkBits+1] >> 1
|
||||
h.links = make([][]uint32, huffmanNumChunks-link)
|
||||
for j := uint(link); j < huffmanNumChunks; j++ {
|
||||
reverse := int(reverseByte[j>>8]) | int(reverseByte[j&0xff])<<8
|
||||
reverse >>= uint(16 - huffmanChunkBits)
|
||||
off := j - uint(link)
|
||||
if sanity && h.chunks[reverse] != 0 {
|
||||
panic("impossible: overwriting existing chunk")
|
||||
}
|
||||
h.chunks[reverse] = uint32(off<<huffmanValueShift | (huffmanChunkBits + 1))
|
||||
h.links[off] = make([]uint32, numLinks)
|
||||
}
|
||||
}
|
||||
|
||||
for i, n := range bits {
|
||||
if n == 0 {
|
||||
continue
|
||||
}
|
||||
code := nextcode[n]
|
||||
nextcode[n]++
|
||||
chunk := uint32(i<<huffmanValueShift | n)
|
||||
reverse := int(reverseByte[code>>8]) | int(reverseByte[code&0xff])<<8
|
||||
reverse >>= uint(16 - n)
|
||||
if n <= huffmanChunkBits {
|
||||
for off := reverse; off < len(h.chunks); off += 1 << uint(n) {
|
||||
// We should never need to overwrite
|
||||
// an existing chunk. Also, 0 is
|
||||
// never a valid chunk, because the
|
||||
// lower 4 "count" bits should be
|
||||
// between 1 and 15.
|
||||
if sanity && h.chunks[off] != 0 {
|
||||
panic("impossible: overwriting existing chunk")
|
||||
}
|
||||
h.chunks[off] = chunk
|
||||
}
|
||||
} else {
|
||||
j := reverse & (huffmanNumChunks - 1)
|
||||
if sanity && h.chunks[j]&huffmanCountMask != huffmanChunkBits+1 {
|
||||
// Longer codes should have been
|
||||
// associated with a link table above.
|
||||
panic("impossible: not an indirect chunk")
|
||||
}
|
||||
value := h.chunks[j] >> huffmanValueShift
|
||||
linktab := h.links[value]
|
||||
reverse >>= huffmanChunkBits
|
||||
for off := reverse; off < len(linktab); off += 1 << uint(n-huffmanChunkBits) {
|
||||
if sanity && linktab[off] != 0 {
|
||||
panic("impossible: overwriting existing chunk")
|
||||
}
|
||||
linktab[off] = chunk
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if sanity {
|
||||
// Above we've sanity checked that we never overwrote
|
||||
// an existing entry. Here we additionally check that
|
||||
// we filled the tables completely.
|
||||
for i, chunk := range h.chunks {
|
||||
if chunk == 0 {
|
||||
// As an exception, in the degenerate
|
||||
// single-code case, we allow odd
|
||||
// chunks to be missing.
|
||||
if code == 1 && i%2 == 1 {
|
||||
continue
|
||||
}
|
||||
panic("impossible: missing chunk")
|
||||
}
|
||||
}
|
||||
for _, linktab := range h.links {
|
||||
for _, chunk := range linktab {
|
||||
if chunk == 0 {
|
||||
panic("impossible: missing chunk")
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return true
|
||||
}
|
||||
|
||||
// The actual read interface needed by NewReader.
|
||||
// If the passed in io.Reader does not also have ReadByte,
|
||||
// the NewReader will introduce its own buffering.
|
||||
type Reader interface {
|
||||
io.Reader
|
||||
io.ByteReader
|
||||
}
|
||||
|
||||
// Decompress state.
|
||||
type decompressor struct {
|
||||
// Input source.
|
||||
r Reader
|
||||
roffset int64
|
||||
|
||||
// Input bits, in top of b.
|
||||
b uint32
|
||||
nb uint
|
||||
|
||||
// Huffman decoders for literal/length, distance.
|
||||
h1, h2 huffmanDecoder
|
||||
|
||||
// Length arrays used to define Huffman codes.
|
||||
bits *[maxNumLit + maxNumDist]int
|
||||
codebits *[numCodes]int
|
||||
|
||||
// Output history, buffer.
|
||||
dict dictDecoder
|
||||
|
||||
// Temporary buffer (avoids repeated allocation).
|
||||
buf [4]byte
|
||||
|
||||
// Next step in the decompression,
|
||||
// and decompression state.
|
||||
step func(*decompressor)
|
||||
stepState int
|
||||
final bool
|
||||
err error
|
||||
toRead []byte
|
||||
hl, hd *huffmanDecoder
|
||||
copyLen int
|
||||
copyDist int
|
||||
}
|
||||
|
||||
func (f *decompressor) nextBlock() {
|
||||
for f.nb < 1+2 {
|
||||
if f.err = f.moreBits(); f.err != nil {
|
||||
return
|
||||
}
|
||||
}
|
||||
f.final = f.b&1 == 1
|
||||
f.b >>= 1
|
||||
typ := f.b & 3
|
||||
f.b >>= 2
|
||||
f.nb -= 1 + 2
|
||||
switch typ {
|
||||
case 0:
|
||||
f.dataBlock()
|
||||
case 1:
|
||||
// compressed, fixed Huffman tables
|
||||
f.hl = &fixedHuffmanDecoder
|
||||
f.hd = nil
|
||||
f.huffmanBlock()
|
||||
case 2:
|
||||
// compressed, dynamic Huffman tables
|
||||
if f.err = f.readHuffman(); f.err != nil {
|
||||
break
|
||||
}
|
||||
f.hl = &f.h1
|
||||
f.hd = &f.h2
|
||||
f.huffmanBlock()
|
||||
default:
|
||||
// 3 is reserved.
|
||||
f.err = CorruptInputError(f.roffset)
|
||||
}
|
||||
}
|
||||
|
||||
func (f *decompressor) Read(b []byte) (int, error) {
|
||||
for {
|
||||
if len(f.toRead) > 0 {
|
||||
n := copy(b, f.toRead)
|
||||
f.toRead = f.toRead[n:]
|
||||
if len(f.toRead) == 0 {
|
||||
return n, f.err
|
||||
}
|
||||
return n, nil
|
||||
}
|
||||
if f.err != nil {
|
||||
return 0, f.err
|
||||
}
|
||||
f.step(f)
|
||||
if f.err != nil && len(f.toRead) == 0 {
|
||||
f.toRead = f.dict.readFlush() // Flush what's left in case of error
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Support the io.WriteTo interface for io.Copy and friends.
|
||||
func (f *decompressor) WriteTo(w io.Writer) (int64, error) {
|
||||
total := int64(0)
|
||||
flushed := false
|
||||
for {
|
||||
if len(f.toRead) > 0 {
|
||||
n, err := w.Write(f.toRead)
|
||||
total += int64(n)
|
||||
if err != nil {
|
||||
f.err = err
|
||||
return total, err
|
||||
}
|
||||
if n != len(f.toRead) {
|
||||
return total, io.ErrShortWrite
|
||||
}
|
||||
f.toRead = f.toRead[:0]
|
||||
}
|
||||
if f.err != nil && flushed {
|
||||
if f.err == io.EOF {
|
||||
return total, nil
|
||||
}
|
||||
return total, f.err
|
||||
}
|
||||
if f.err == nil {
|
||||
f.step(f)
|
||||
}
|
||||
if len(f.toRead) == 0 && f.err != nil && !flushed {
|
||||
f.toRead = f.dict.readFlush() // Flush what's left in case of error
|
||||
flushed = true
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func (f *decompressor) Close() error {
|
||||
if f.err == io.EOF {
|
||||
return nil
|
||||
}
|
||||
return f.err
|
||||
}
|
||||
|
||||
// RFC 1951 section 3.2.7.
|
||||
// Compression with dynamic Huffman codes
|
||||
|
||||
var codeOrder = [...]int{16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}
|
||||
|
||||
func (f *decompressor) readHuffman() error {
|
||||
// HLIT[5], HDIST[5], HCLEN[4].
|
||||
for f.nb < 5+5+4 {
|
||||
if err := f.moreBits(); err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
nlit := int(f.b&0x1F) + 257
|
||||
if nlit > maxNumLit {
|
||||
return CorruptInputError(f.roffset)
|
||||
}
|
||||
f.b >>= 5
|
||||
ndist := int(f.b&0x1F) + 1
|
||||
if ndist > maxNumDist {
|
||||
return CorruptInputError(f.roffset)
|
||||
}
|
||||
f.b >>= 5
|
||||
nclen := int(f.b&0xF) + 4
|
||||
// numCodes is 19, so nclen is always valid.
|
||||
f.b >>= 4
|
||||
f.nb -= 5 + 5 + 4
|
||||
|
||||
// (HCLEN+4)*3 bits: code lengths in the magic codeOrder order.
|
||||
for i := 0; i < nclen; i++ {
|
||||
for f.nb < 3 {
|
||||
if err := f.moreBits(); err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
f.codebits[codeOrder[i]] = int(f.b & 0x7)
|
||||
f.b >>= 3
|
||||
f.nb -= 3
|
||||
}
|
||||
for i := nclen; i < len(codeOrder); i++ {
|
||||
f.codebits[codeOrder[i]] = 0
|
||||
}
|
||||
if !f.h1.init(f.codebits[0:]) {
|
||||
return CorruptInputError(f.roffset)
|
||||
}
|
||||
|
||||
// HLIT + 257 code lengths, HDIST + 1 code lengths,
|
||||
// using the code length Huffman code.
|
||||
for i, n := 0, nlit+ndist; i < n; {
|
||||
x, err := f.huffSym(&f.h1)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
if x < 16 {
|
||||
// Actual length.
|
||||
f.bits[i] = x
|
||||
i++
|
||||
continue
|
||||
}
|
||||
// Repeat previous length or zero.
|
||||
var rep int
|
||||
var nb uint
|
||||
var b int
|
||||
switch x {
|
||||
default:
|
||||
return InternalError("unexpected length code")
|
||||
case 16:
|
||||
rep = 3
|
||||
nb = 2
|
||||
if i == 0 {
|
||||
return CorruptInputError(f.roffset)
|
||||
}
|
||||
b = f.bits[i-1]
|
||||
case 17:
|
||||
rep = 3
|
||||
nb = 3
|
||||
b = 0
|
||||
case 18:
|
||||
rep = 11
|
||||
nb = 7
|
||||
b = 0
|
||||
}
|
||||
for f.nb < nb {
|
||||
if err := f.moreBits(); err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
rep += int(f.b & uint32(1<<nb-1))
|
||||
f.b >>= nb
|
||||
f.nb -= nb
|
||||
if i+rep > n {
|
||||
return CorruptInputError(f.roffset)
|
||||
}
|
||||
for j := 0; j < rep; j++ {
|
||||
f.bits[i] = b
|
||||
i++
|
||||
}
|
||||
}
|
||||
|
||||
if !f.h1.init(f.bits[0:nlit]) || !f.h2.init(f.bits[nlit:nlit+ndist]) {
|
||||
return CorruptInputError(f.roffset)
|
||||
}
|
||||
|
||||
// As an optimization, we can initialize the min bits to read at a time
|
||||
// for the HLIT tree to the length of the EOB marker since we know that
|
||||
// every block must terminate with one. This preserves the property that
|
||||
// we never read any extra bytes after the end of the DEFLATE stream.
|
||||
if f.h1.min < f.bits[endBlockMarker] {
|
||||
f.h1.min = f.bits[endBlockMarker]
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// Decode a single Huffman block from f.
|
||||
// hl and hd are the Huffman states for the lit/length values
|
||||
// and the distance values, respectively. If hd == nil, using the
|
||||
// fixed distance encoding associated with fixed Huffman blocks.
|
||||
func (f *decompressor) huffmanBlock() {
|
||||
const (
|
||||
stateInit = iota // Zero value must be stateInit
|
||||
stateDict
|
||||
)
|
||||
|
||||
switch f.stepState {
|
||||
case stateInit:
|
||||
goto readLiteral
|
||||
case stateDict:
|
||||
goto copyHistory
|
||||
}
|
||||
|
||||
readLiteral:
|
||||
// Read literal and/or (length, distance) according to RFC section 3.2.3.
|
||||
{
|
||||
v, err := f.huffSym(f.hl)
|
||||
if err != nil {
|
||||
f.err = err
|
||||
return
|
||||
}
|
||||
var n uint // number of bits extra
|
||||
var length int
|
||||
switch {
|
||||
case v < 256:
|
||||
f.dict.writeByte(byte(v))
|
||||
if f.dict.availWrite() == 0 {
|
||||
f.toRead = f.dict.readFlush()
|
||||
f.step = (*decompressor).huffmanBlock
|
||||
f.stepState = stateInit
|
||||
return
|
||||
}
|
||||
goto readLiteral
|
||||
case v == 256:
|
||||
f.finishBlock()
|
||||
return
|
||||
// otherwise, reference to older data
|
||||
case v < 265:
|
||||
length = v - (257 - 3)
|
||||
n = 0
|
||||
case v < 269:
|
||||
length = v*2 - (265*2 - 11)
|
||||
n = 1
|
||||
case v < 273:
|
||||
length = v*4 - (269*4 - 19)
|
||||
n = 2
|
||||
case v < 277:
|
||||
length = v*8 - (273*8 - 35)
|
||||
n = 3
|
||||
case v < 281:
|
||||
length = v*16 - (277*16 - 67)
|
||||
n = 4
|
||||
case v < 285:
|
||||
length = v*32 - (281*32 - 131)
|
||||
n = 5
|
||||
case v < maxNumLit:
|
||||
length = 258
|
||||
n = 0
|
||||
default:
|
||||
f.err = CorruptInputError(f.roffset)
|
||||
return
|
||||
}
|
||||
if n > 0 {
|
||||
for f.nb < n {
|
||||
if err = f.moreBits(); err != nil {
|
||||
f.err = err
|
||||
return
|
||||
}
|
||||
}
|
||||
length += int(f.b & uint32(1<<n-1))
|
||||
f.b >>= n
|
||||
f.nb -= n
|
||||
}
|
||||
|
||||
var dist int
|
||||
if f.hd == nil {
|
||||
for f.nb < 5 {
|
||||
if err = f.moreBits(); err != nil {
|
||||
f.err = err
|
||||
return
|
||||
}
|
||||
}
|
||||
dist = int(reverseByte[(f.b&0x1F)<<3])
|
||||
f.b >>= 5
|
||||
f.nb -= 5
|
||||
} else {
|
||||
if dist, err = f.huffSym(f.hd); err != nil {
|
||||
f.err = err
|
||||
return
|
||||
}
|
||||
}
|
||||
|
||||
switch {
|
||||
case dist < 4:
|
||||
dist++
|
||||
case dist < maxNumDist:
|
||||
nb := uint(dist-2) >> 1
|
||||
// have 1 bit in bottom of dist, need nb more.
|
||||
extra := (dist & 1) << nb
|
||||
for f.nb < nb {
|
||||
if err = f.moreBits(); err != nil {
|
||||
f.err = err
|
||||
return
|
||||
}
|
||||
}
|
||||
extra |= int(f.b & uint32(1<<nb-1))
|
||||
f.b >>= nb
|
||||
f.nb -= nb
|
||||
dist = 1<<(nb+1) + 1 + extra
|
||||
default:
|
||||
f.err = CorruptInputError(f.roffset)
|
||||
return
|
||||
}
|
||||
|
||||
// No check on length; encoding can be prescient.
|
||||
if dist > f.dict.histSize() {
|
||||
f.err = CorruptInputError(f.roffset)
|
||||
return
|
||||
}
|
||||
|
||||
f.copyLen, f.copyDist = length, dist
|
||||
goto copyHistory
|
||||
}
|
||||
|
||||
copyHistory:
|
||||
// Perform a backwards copy according to RFC section 3.2.3.
|
||||
{
|
||||
cnt := f.dict.tryWriteCopy(f.copyDist, f.copyLen)
|
||||
if cnt == 0 {
|
||||
cnt = f.dict.writeCopy(f.copyDist, f.copyLen)
|
||||
}
|
||||
f.copyLen -= cnt
|
||||
|
||||
if f.dict.availWrite() == 0 || f.copyLen > 0 {
|
||||
f.toRead = f.dict.readFlush()
|
||||
f.step = (*decompressor).huffmanBlock // We need to continue this work
|
||||
f.stepState = stateDict
|
||||
return
|
||||
}
|
||||
goto readLiteral
|
||||
}
|
||||
}
|
||||
|
||||
// Copy a single uncompressed data block from input to output.
|
||||
func (f *decompressor) dataBlock() {
|
||||
// Uncompressed.
|
||||
// Discard current half-byte.
|
||||
f.nb = 0
|
||||
f.b = 0
|
||||
|
||||
// Length then ones-complement of length.
|
||||
nr, err := io.ReadFull(f.r, f.buf[0:4])
|
||||
f.roffset += int64(nr)
|
||||
if err != nil {
|
||||
if err == io.EOF {
|
||||
err = io.ErrUnexpectedEOF
|
||||
}
|
||||
f.err = err
|
||||
return
|
||||
}
|
||||
n := int(f.buf[0]) | int(f.buf[1])<<8
|
||||
nn := int(f.buf[2]) | int(f.buf[3])<<8
|
||||
if uint16(nn) != uint16(^n) {
|
||||
f.err = CorruptInputError(f.roffset)
|
||||
return
|
||||
}
|
||||
|
||||
if n == 0 {
|
||||
f.toRead = f.dict.readFlush()
|
||||
f.finishBlock()
|
||||
return
|
||||
}
|
||||
|
||||
f.copyLen = n
|
||||
f.copyData()
|
||||
}
|
||||
|
||||
// copyData copies f.copyLen bytes from the underlying reader into f.hist.
|
||||
// It pauses for reads when f.hist is full.
|
||||
func (f *decompressor) copyData() {
|
||||
buf := f.dict.writeSlice()
|
||||
if len(buf) > f.copyLen {
|
||||
buf = buf[:f.copyLen]
|
||||
}
|
||||
|
||||
cnt, err := io.ReadFull(f.r, buf)
|
||||
f.roffset += int64(cnt)
|
||||
f.copyLen -= cnt
|
||||
f.dict.writeMark(cnt)
|
||||
if err != nil {
|
||||
if err == io.EOF {
|
||||
err = io.ErrUnexpectedEOF
|
||||
}
|
||||
f.err = err
|
||||
return
|
||||
}
|
||||
|
||||
if f.dict.availWrite() == 0 || f.copyLen > 0 {
|
||||
f.toRead = f.dict.readFlush()
|
||||
f.step = (*decompressor).copyData
|
||||
return
|
||||
}
|
||||
f.finishBlock()
|
||||
}
|
||||
|
||||
func (f *decompressor) finishBlock() {
|
||||
if f.final {
|
||||
if f.dict.availRead() > 0 {
|
||||
f.toRead = f.dict.readFlush()
|
||||
}
|
||||
f.err = io.EOF
|
||||
}
|
||||
f.step = (*decompressor).nextBlock
|
||||
}
|
||||
|
||||
func (f *decompressor) moreBits() error {
|
||||
c, err := f.r.ReadByte()
|
||||
if err != nil {
|
||||
if err == io.EOF {
|
||||
err = io.ErrUnexpectedEOF
|
||||
}
|
||||
return err
|
||||
}
|
||||
f.roffset++
|
||||
f.b |= uint32(c) << f.nb
|
||||
f.nb += 8
|
||||
return nil
|
||||
}
|
||||
|
||||
// Read the next Huffman-encoded symbol from f according to h.
|
||||
func (f *decompressor) huffSym(h *huffmanDecoder) (int, error) {
|
||||
// Since a huffmanDecoder can be empty or be composed of a degenerate tree
|
||||
// with single element, huffSym must error on these two edge cases. In both
|
||||
// cases, the chunks slice will be 0 for the invalid sequence, leading it
|
||||
// satisfy the n == 0 check below.
|
||||
n := uint(h.min)
|
||||
for {
|
||||
for f.nb < n {
|
||||
if err := f.moreBits(); err != nil {
|
||||
return 0, err
|
||||
}
|
||||
}
|
||||
chunk := h.chunks[f.b&(huffmanNumChunks-1)]
|
||||
n = uint(chunk & huffmanCountMask)
|
||||
if n > huffmanChunkBits {
|
||||
chunk = h.links[chunk>>huffmanValueShift][(f.b>>huffmanChunkBits)&h.linkMask]
|
||||
n = uint(chunk & huffmanCountMask)
|
||||
}
|
||||
if n <= f.nb {
|
||||
if n == 0 {
|
||||
f.err = CorruptInputError(f.roffset)
|
||||
return 0, f.err
|
||||
}
|
||||
f.b >>= n
|
||||
f.nb -= n
|
||||
return int(chunk >> huffmanValueShift), nil
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func makeReader(r io.Reader) Reader {
|
||||
if rr, ok := r.(Reader); ok {
|
||||
return rr
|
||||
}
|
||||
return bufio.NewReader(r)
|
||||
}
|
||||
|
||||
func fixedHuffmanDecoderInit() {
|
||||
fixedOnce.Do(func() {
|
||||
// These come from the RFC section 3.2.6.
|
||||
var bits [288]int
|
||||
for i := 0; i < 144; i++ {
|
||||
bits[i] = 8
|
||||
}
|
||||
for i := 144; i < 256; i++ {
|
||||
bits[i] = 9
|
||||
}
|
||||
for i := 256; i < 280; i++ {
|
||||
bits[i] = 7
|
||||
}
|
||||
for i := 280; i < 288; i++ {
|
||||
bits[i] = 8
|
||||
}
|
||||
fixedHuffmanDecoder.init(bits[:])
|
||||
})
|
||||
}
|
||||
|
||||
func (f *decompressor) Reset(r io.Reader, dict []byte) error {
|
||||
*f = decompressor{
|
||||
r: makeReader(r),
|
||||
bits: f.bits,
|
||||
codebits: f.codebits,
|
||||
dict: f.dict,
|
||||
step: (*decompressor).nextBlock,
|
||||
}
|
||||
f.dict.init(maxMatchOffset, dict)
|
||||
return nil
|
||||
}
|
||||
|
||||
// NewReader returns a new ReadCloser that can be used
|
||||
// to read the uncompressed version of r.
|
||||
// If r does not also implement io.ByteReader,
|
||||
// the decompressor may read more data than necessary from r.
|
||||
// It is the caller's responsibility to call Close on the ReadCloser
|
||||
// when finished reading.
|
||||
//
|
||||
// The ReadCloser returned by NewReader also implements Resetter.
|
||||
func NewReader(r io.Reader) io.ReadCloser {
|
||||
fixedHuffmanDecoderInit()
|
||||
|
||||
var f decompressor
|
||||
f.r = makeReader(r)
|
||||
f.bits = new([maxNumLit + maxNumDist]int)
|
||||
f.codebits = new([numCodes]int)
|
||||
f.step = (*decompressor).nextBlock
|
||||
f.dict.init(maxMatchOffset, nil)
|
||||
return &f
|
||||
}
|
||||
|
||||
// NewReaderDict is like NewReader but initializes the reader
|
||||
// with a preset dictionary. The returned Reader behaves as if
|
||||
// the uncompressed data stream started with the given dictionary,
|
||||
// which has already been read. NewReaderDict is typically used
|
||||
// to read data compressed by NewWriterDict.
|
||||
//
|
||||
// The ReadCloser returned by NewReader also implements Resetter.
|
||||
func NewReaderDict(r io.Reader, dict []byte) io.ReadCloser {
|
||||
fixedHuffmanDecoderInit()
|
||||
|
||||
var f decompressor
|
||||
f.r = makeReader(r)
|
||||
f.bits = new([maxNumLit + maxNumDist]int)
|
||||
f.codebits = new([numCodes]int)
|
||||
f.step = (*decompressor).nextBlock
|
||||
f.dict.init(maxMatchOffset, dict)
|
||||
return &f
|
||||
}
|
282
vendor/github.com/klauspost/compress/flate/inflate_test.go
generated
vendored
Normal file
282
vendor/github.com/klauspost/compress/flate/inflate_test.go
generated
vendored
Normal file
@@ -0,0 +1,282 @@
|
||||
// Copyright 2014 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package flate
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"crypto/rand"
|
||||
"io"
|
||||
"io/ioutil"
|
||||
"strconv"
|
||||
"strings"
|
||||
"testing"
|
||||
)
|
||||
|
||||
func TestReset(t *testing.T) {
|
||||
ss := []string{
|
||||
"lorem ipsum izzle fo rizzle",
|
||||
"the quick brown fox jumped over",
|
||||
}
|
||||
|
||||
deflated := make([]bytes.Buffer, 2)
|
||||
for i, s := range ss {
|
||||
w, _ := NewWriter(&deflated[i], 1)
|
||||
w.Write([]byte(s))
|
||||
w.Close()
|
||||
}
|
||||
|
||||
inflated := make([]bytes.Buffer, 2)
|
||||
|
||||
f := NewReader(&deflated[0])
|
||||
io.Copy(&inflated[0], f)
|
||||
f.(Resetter).Reset(&deflated[1], nil)
|
||||
io.Copy(&inflated[1], f)
|
||||
f.Close()
|
||||
|
||||
for i, s := range ss {
|
||||
if s != inflated[i].String() {
|
||||
t.Errorf("inflated[%d]:\ngot %q\nwant %q", i, inflated[i], s)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestReaderTruncated(t *testing.T) {
|
||||
vectors := []struct{ input, output string }{
|
||||
{"\x00", ""},
|
||||
{"\x00\f", ""},
|
||||
{"\x00\f\x00", ""},
|
||||
{"\x00\f\x00\xf3\xff", ""},
|
||||
{"\x00\f\x00\xf3\xffhello", "hello"},
|
||||
{"\x00\f\x00\xf3\xffhello, world", "hello, world"},
|
||||
{"\x02", ""},
|
||||
{"\xf2H\xcd", "He"},
|
||||
{"\xf2H͙0a\u0084\t", "Hel\x90\x90\x90\x90\x90"},
|
||||
{"\xf2H͙0a\u0084\t\x00", "Hel\x90\x90\x90\x90\x90"},
|
||||
}
|
||||
|
||||
for i, v := range vectors {
|
||||
r := strings.NewReader(v.input)
|
||||
zr := NewReader(r)
|
||||
b, err := ioutil.ReadAll(zr)
|
||||
if err != io.ErrUnexpectedEOF {
|
||||
t.Errorf("test %d, error mismatch: got %v, want io.ErrUnexpectedEOF", i, err)
|
||||
}
|
||||
if string(b) != v.output {
|
||||
t.Errorf("test %d, output mismatch: got %q, want %q", i, b, v.output)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestResetDict(t *testing.T) {
|
||||
dict := []byte("the lorem fox")
|
||||
ss := []string{
|
||||
"lorem ipsum izzle fo rizzle",
|
||||
"the quick brown fox jumped over",
|
||||
}
|
||||
|
||||
deflated := make([]bytes.Buffer, len(ss))
|
||||
for i, s := range ss {
|
||||
w, _ := NewWriterDict(&deflated[i], DefaultCompression, dict)
|
||||
w.Write([]byte(s))
|
||||
w.Close()
|
||||
}
|
||||
|
||||
inflated := make([]bytes.Buffer, len(ss))
|
||||
|
||||
f := NewReader(nil)
|
||||
for i := range inflated {
|
||||
f.(Resetter).Reset(&deflated[i], dict)
|
||||
io.Copy(&inflated[i], f)
|
||||
}
|
||||
f.Close()
|
||||
|
||||
for i, s := range ss {
|
||||
if s != inflated[i].String() {
|
||||
t.Errorf("inflated[%d]:\ngot %q\nwant %q", i, inflated[i], s)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Tests ported from zlib/test/infcover.c
|
||||
type infTest struct {
|
||||
hex string
|
||||
id string
|
||||
n int
|
||||
}
|
||||
|
||||
var infTests = []infTest{
|
||||
{"0 0 0 0 0", "invalid stored block lengths", 1},
|
||||
{"3 0", "fixed", 0},
|
||||
{"6", "invalid block type", 1},
|
||||
{"1 1 0 fe ff 0", "stored", 0},
|
||||
{"fc 0 0", "too many length or distance symbols", 1},
|
||||
{"4 0 fe ff", "invalid code lengths set", 1},
|
||||
{"4 0 24 49 0", "invalid bit length repeat", 1},
|
||||
{"4 0 24 e9 ff ff", "invalid bit length repeat", 1},
|
||||
{"4 0 24 e9 ff 6d", "invalid code -- missing end-of-block", 1},
|
||||
{"4 80 49 92 24 49 92 24 71 ff ff 93 11 0", "invalid literal/lengths set", 1},
|
||||
{"4 80 49 92 24 49 92 24 f b4 ff ff c3 84", "invalid distances set", 1},
|
||||
{"4 c0 81 8 0 0 0 0 20 7f eb b 0 0", "invalid literal/length code", 1},
|
||||
{"2 7e ff ff", "invalid distance code", 1},
|
||||
{"c c0 81 0 0 0 0 0 90 ff 6b 4 0", "invalid distance too far back", 1},
|
||||
|
||||
// also trailer mismatch just in inflate()
|
||||
{"1f 8b 8 0 0 0 0 0 0 0 3 0 0 0 0 1", "incorrect data check", -1},
|
||||
{"1f 8b 8 0 0 0 0 0 0 0 3 0 0 0 0 0 0 0 0 1", "incorrect length check", -1},
|
||||
{"5 c0 21 d 0 0 0 80 b0 fe 6d 2f 91 6c", "pull 17", 0},
|
||||
{"5 e0 81 91 24 cb b2 2c 49 e2 f 2e 8b 9a 47 56 9f fb fe ec d2 ff 1f", "long code", 0},
|
||||
{"ed c0 1 1 0 0 0 40 20 ff 57 1b 42 2c 4f", "length extra", 0},
|
||||
{"ed cf c1 b1 2c 47 10 c4 30 fa 6f 35 1d 1 82 59 3d fb be 2e 2a fc f c", "long distance and extra", 0},
|
||||
{"ed c0 81 0 0 0 0 80 a0 fd a9 17 a9 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 6", "window end", 0},
|
||||
}
|
||||
|
||||
func TestInflate(t *testing.T) {
|
||||
for _, test := range infTests {
|
||||
hex := strings.Split(test.hex, " ")
|
||||
data := make([]byte, len(hex))
|
||||
for i, h := range hex {
|
||||
b, _ := strconv.ParseInt(h, 16, 32)
|
||||
data[i] = byte(b)
|
||||
}
|
||||
buf := bytes.NewReader(data)
|
||||
r := NewReader(buf)
|
||||
|
||||
_, err := io.Copy(ioutil.Discard, r)
|
||||
if (test.n == 0 && err == nil) || (test.n != 0 && err != nil) {
|
||||
t.Logf("%q: OK:", test.id)
|
||||
t.Logf(" - got %v", err)
|
||||
continue
|
||||
}
|
||||
|
||||
if test.n == 0 && err != nil {
|
||||
t.Errorf("%q: Expected no error, but got %v", test.id, err)
|
||||
continue
|
||||
}
|
||||
|
||||
if test.n != 0 && err == nil {
|
||||
t.Errorf("%q:Expected an error, but got none", test.id)
|
||||
continue
|
||||
}
|
||||
t.Fatal(test.n, err)
|
||||
}
|
||||
|
||||
for _, test := range infOutTests {
|
||||
hex := strings.Split(test.hex, " ")
|
||||
data := make([]byte, len(hex))
|
||||
for i, h := range hex {
|
||||
b, _ := strconv.ParseInt(h, 16, 32)
|
||||
data[i] = byte(b)
|
||||
}
|
||||
buf := bytes.NewReader(data)
|
||||
r := NewReader(buf)
|
||||
|
||||
_, err := io.Copy(ioutil.Discard, r)
|
||||
if test.err == (err != nil) {
|
||||
t.Logf("%q: OK:", test.id)
|
||||
t.Logf(" - got %v", err)
|
||||
continue
|
||||
}
|
||||
|
||||
if test.err == false && err != nil {
|
||||
t.Errorf("%q: Expected no error, but got %v", test.id, err)
|
||||
continue
|
||||
}
|
||||
|
||||
if test.err && err == nil {
|
||||
t.Errorf("%q: Expected an error, but got none", test.id)
|
||||
continue
|
||||
}
|
||||
t.Fatal(test.err, err)
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
// Tests ported from zlib/test/infcover.c
|
||||
// Since zlib inflate is push (writer) instead of pull (reader)
|
||||
// some of the window size tests have been removed, since they
|
||||
// are irrelevant.
|
||||
type infOutTest struct {
|
||||
hex string
|
||||
id string
|
||||
step int
|
||||
win int
|
||||
length int
|
||||
err bool
|
||||
}
|
||||
|
||||
var infOutTests = []infOutTest{
|
||||
{"2 8 20 80 0 3 0", "inflate_fast TYPE return", 0, -15, 258, false},
|
||||
{"63 18 5 40 c 0", "window wrap", 3, -8, 300, false},
|
||||
{"e5 e0 81 ad 6d cb b2 2c c9 01 1e 59 63 ae 7d ee fb 4d fd b5 35 41 68 ff 7f 0f 0 0 0", "fast length extra bits", 0, -8, 258, true},
|
||||
{"25 fd 81 b5 6d 59 b6 6a 49 ea af 35 6 34 eb 8c b9 f6 b9 1e ef 67 49 50 fe ff ff 3f 0 0", "fast distance extra bits", 0, -8, 258, true},
|
||||
{"3 7e 0 0 0 0 0", "fast invalid distance code", 0, -8, 258, true},
|
||||
{"1b 7 0 0 0 0 0", "fast invalid literal/length code", 0, -8, 258, true},
|
||||
{"d c7 1 ae eb 38 c 4 41 a0 87 72 de df fb 1f b8 36 b1 38 5d ff ff 0", "fast 2nd level codes and too far back", 0, -8, 258, true},
|
||||
{"63 18 5 8c 10 8 0 0 0 0", "very common case", 0, -8, 259, false},
|
||||
{"63 60 60 18 c9 0 8 18 18 18 26 c0 28 0 29 0 0 0", "contiguous and wrap around window", 6, -8, 259, false},
|
||||
{"63 0 3 0 0 0 0 0", "copy direct from output", 0, -8, 259, false},
|
||||
{"1f 8b 0 0", "bad gzip method", 0, 31, 0, true},
|
||||
{"1f 8b 8 80", "bad gzip flags", 0, 31, 0, true},
|
||||
{"77 85", "bad zlib method", 0, 15, 0, true},
|
||||
{"78 9c", "bad zlib window size", 0, 8, 0, true},
|
||||
{"1f 8b 8 1e 0 0 0 0 0 0 1 0 0 0 0 0 0", "bad header crc", 0, 47, 1, true},
|
||||
{"1f 8b 8 2 0 0 0 0 0 0 1d 26 3 0 0 0 0 0 0 0 0 0", "check gzip length", 0, 47, 0, true},
|
||||
{"78 90", "bad zlib header check", 0, 47, 0, true},
|
||||
{"8 b8 0 0 0 1", "need dictionary", 0, 8, 0, true},
|
||||
{"63 18 68 30 d0 0 0", "force split window update", 4, -8, 259, false},
|
||||
{"3 0", "use fixed blocks", 0, -15, 1, false},
|
||||
{"", "bad window size", 0, 1, 0, true},
|
||||
}
|
||||
|
||||
func TestWriteTo(t *testing.T) {
|
||||
input := make([]byte, 100000)
|
||||
n, err := rand.Read(input)
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
if n != len(input) {
|
||||
t.Fatal("did not fill buffer")
|
||||
}
|
||||
compressed := &bytes.Buffer{}
|
||||
w, err := NewWriter(compressed, -2)
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
n, err = w.Write(input)
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
if n != len(input) {
|
||||
t.Fatal("did not fill buffer")
|
||||
}
|
||||
w.Close()
|
||||
buf := compressed.Bytes()
|
||||
|
||||
dec := NewReader(bytes.NewBuffer(buf))
|
||||
// ReadAll does not use WriteTo, but we wrap it in a NopCloser to be sure.
|
||||
readall, err := ioutil.ReadAll(ioutil.NopCloser(dec))
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
if len(readall) != len(input) {
|
||||
t.Fatal("did not decompress everything")
|
||||
}
|
||||
|
||||
dec = NewReader(bytes.NewBuffer(buf))
|
||||
wtbuf := &bytes.Buffer{}
|
||||
written, err := dec.(io.WriterTo).WriteTo(wtbuf)
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
if written != int64(len(input)) {
|
||||
t.Error("Returned length did not match, expected", len(input), "got", written)
|
||||
}
|
||||
if wtbuf.Len() != len(input) {
|
||||
t.Error("Actual Length did not match, expected", len(input), "got", wtbuf.Len())
|
||||
}
|
||||
if bytes.Compare(wtbuf.Bytes(), input) != 0 {
|
||||
t.Fatal("output did not match input")
|
||||
}
|
||||
}
|
97
vendor/github.com/klauspost/compress/flate/reader_test.go
generated
vendored
Normal file
97
vendor/github.com/klauspost/compress/flate/reader_test.go
generated
vendored
Normal file
@@ -0,0 +1,97 @@
|
||||
// Copyright 2012 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package flate
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"io"
|
||||
"io/ioutil"
|
||||
"runtime"
|
||||
"strings"
|
||||
"testing"
|
||||
)
|
||||
|
||||
func TestNlitOutOfRange(t *testing.T) {
|
||||
// Trying to decode this bogus flate data, which has a Huffman table
|
||||
// with nlit=288, should not panic.
|
||||
io.Copy(ioutil.Discard, NewReader(strings.NewReader(
|
||||
"\xfc\xfe\x36\xe7\x5e\x1c\xef\xb3\x55\x58\x77\xb6\x56\xb5\x43\xf4"+
|
||||
"\x6f\xf2\xd2\xe6\x3d\x99\xa0\x85\x8c\x48\xeb\xf8\xda\x83\x04\x2a"+
|
||||
"\x75\xc4\xf8\x0f\x12\x11\xb9\xb4\x4b\x09\xa0\xbe\x8b\x91\x4c")))
|
||||
}
|
||||
|
||||
const (
|
||||
digits = iota
|
||||
twain
|
||||
)
|
||||
|
||||
var testfiles = []string{
|
||||
// Digits is the digits of the irrational number e. Its decimal representation
|
||||
// does not repeat, but there are only 10 possible digits, so it should be
|
||||
// reasonably compressible.
|
||||
digits: "../testdata/e.txt",
|
||||
// Twain is Project Gutenberg's edition of Mark Twain's classic English novel.
|
||||
twain: "../testdata/Mark.Twain-Tom.Sawyer.txt",
|
||||
}
|
||||
|
||||
func benchmarkDecode(b *testing.B, testfile, level, n int) {
|
||||
b.ReportAllocs()
|
||||
b.StopTimer()
|
||||
b.SetBytes(int64(n))
|
||||
buf0, err := ioutil.ReadFile(testfiles[testfile])
|
||||
if err != nil {
|
||||
b.Fatal(err)
|
||||
}
|
||||
if len(buf0) == 0 {
|
||||
b.Fatalf("test file %q has no data", testfiles[testfile])
|
||||
}
|
||||
compressed := new(bytes.Buffer)
|
||||
w, err := NewWriter(compressed, level)
|
||||
if err != nil {
|
||||
b.Fatal(err)
|
||||
}
|
||||
for i := 0; i < n; i += len(buf0) {
|
||||
if len(buf0) > n-i {
|
||||
buf0 = buf0[:n-i]
|
||||
}
|
||||
io.Copy(w, bytes.NewReader(buf0))
|
||||
}
|
||||
w.Close()
|
||||
buf1 := compressed.Bytes()
|
||||
buf0, compressed, w = nil, nil, nil
|
||||
runtime.GC()
|
||||
b.StartTimer()
|
||||
for i := 0; i < b.N; i++ {
|
||||
io.Copy(ioutil.Discard, NewReader(bytes.NewReader(buf1)))
|
||||
}
|
||||
}
|
||||
|
||||
// These short names are so that gofmt doesn't break the BenchmarkXxx function
|
||||
// bodies below over multiple lines.
|
||||
const (
|
||||
constant = ConstantCompression
|
||||
speed = BestSpeed
|
||||
default_ = DefaultCompression
|
||||
compress = BestCompression
|
||||
)
|
||||
|
||||
func BenchmarkDecodeDigitsSpeed1e4(b *testing.B) { benchmarkDecode(b, digits, speed, 1e4) }
|
||||
func BenchmarkDecodeDigitsSpeed1e5(b *testing.B) { benchmarkDecode(b, digits, speed, 1e5) }
|
||||
func BenchmarkDecodeDigitsSpeed1e6(b *testing.B) { benchmarkDecode(b, digits, speed, 1e6) }
|
||||
func BenchmarkDecodeDigitsDefault1e4(b *testing.B) { benchmarkDecode(b, digits, default_, 1e4) }
|
||||
func BenchmarkDecodeDigitsDefault1e5(b *testing.B) { benchmarkDecode(b, digits, default_, 1e5) }
|
||||
func BenchmarkDecodeDigitsDefault1e6(b *testing.B) { benchmarkDecode(b, digits, default_, 1e6) }
|
||||
func BenchmarkDecodeDigitsCompress1e4(b *testing.B) { benchmarkDecode(b, digits, compress, 1e4) }
|
||||
func BenchmarkDecodeDigitsCompress1e5(b *testing.B) { benchmarkDecode(b, digits, compress, 1e5) }
|
||||
func BenchmarkDecodeDigitsCompress1e6(b *testing.B) { benchmarkDecode(b, digits, compress, 1e6) }
|
||||
func BenchmarkDecodeTwainSpeed1e4(b *testing.B) { benchmarkDecode(b, twain, speed, 1e4) }
|
||||
func BenchmarkDecodeTwainSpeed1e5(b *testing.B) { benchmarkDecode(b, twain, speed, 1e5) }
|
||||
func BenchmarkDecodeTwainSpeed1e6(b *testing.B) { benchmarkDecode(b, twain, speed, 1e6) }
|
||||
func BenchmarkDecodeTwainDefault1e4(b *testing.B) { benchmarkDecode(b, twain, default_, 1e4) }
|
||||
func BenchmarkDecodeTwainDefault1e5(b *testing.B) { benchmarkDecode(b, twain, default_, 1e5) }
|
||||
func BenchmarkDecodeTwainDefault1e6(b *testing.B) { benchmarkDecode(b, twain, default_, 1e6) }
|
||||
func BenchmarkDecodeTwainCompress1e4(b *testing.B) { benchmarkDecode(b, twain, compress, 1e4) }
|
||||
func BenchmarkDecodeTwainCompress1e5(b *testing.B) { benchmarkDecode(b, twain, compress, 1e5) }
|
||||
func BenchmarkDecodeTwainCompress1e6(b *testing.B) { benchmarkDecode(b, twain, compress, 1e6) }
|
48
vendor/github.com/klauspost/compress/flate/reverse_bits.go
generated
vendored
Normal file
48
vendor/github.com/klauspost/compress/flate/reverse_bits.go
generated
vendored
Normal file
@@ -0,0 +1,48 @@
|
||||
// Copyright 2009 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package flate
|
||||
|
||||
var reverseByte = [256]byte{
|
||||
0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0,
|
||||
0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
|
||||
0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8,
|
||||
0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
|
||||
0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4,
|
||||
0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
|
||||
0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec,
|
||||
0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
|
||||
0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2,
|
||||
0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
|
||||
0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea,
|
||||
0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
|
||||
0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6,
|
||||
0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
|
||||
0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee,
|
||||
0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
|
||||
0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1,
|
||||
0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
|
||||
0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9,
|
||||
0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
|
||||
0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5,
|
||||
0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
|
||||
0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed,
|
||||
0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
|
||||
0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3,
|
||||
0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
|
||||
0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb,
|
||||
0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
|
||||
0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7,
|
||||
0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
|
||||
0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef,
|
||||
0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff,
|
||||
}
|
||||
|
||||
func reverseUint16(v uint16) uint16 {
|
||||
return uint16(reverseByte[v>>8]) | uint16(reverseByte[v&0xFF])<<8
|
||||
}
|
||||
|
||||
func reverseBits(number uint16, bitLength byte) uint16 {
|
||||
return reverseUint16(number << uint8(16-bitLength))
|
||||
}
|
900
vendor/github.com/klauspost/compress/flate/snappy.go
generated
vendored
Normal file
900
vendor/github.com/klauspost/compress/flate/snappy.go
generated
vendored
Normal file
@@ -0,0 +1,900 @@
|
||||
// Copyright 2011 The Snappy-Go Authors. All rights reserved.
|
||||
// Modified for deflate by Klaus Post (c) 2015.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package flate
|
||||
|
||||
// emitLiteral writes a literal chunk and returns the number of bytes written.
|
||||
func emitLiteral(dst *tokens, lit []byte) {
|
||||
ol := int(dst.n)
|
||||
for i, v := range lit {
|
||||
dst.tokens[(i+ol)&maxStoreBlockSize] = token(v)
|
||||
}
|
||||
dst.n += uint16(len(lit))
|
||||
}
|
||||
|
||||
// emitCopy writes a copy chunk and returns the number of bytes written.
|
||||
func emitCopy(dst *tokens, offset, length int) {
|
||||
dst.tokens[dst.n] = matchToken(uint32(length-3), uint32(offset-minOffsetSize))
|
||||
dst.n++
|
||||
}
|
||||
|
||||
type snappyEnc interface {
|
||||
Encode(dst *tokens, src []byte)
|
||||
Reset()
|
||||
}
|
||||
|
||||
func newSnappy(level int) snappyEnc {
|
||||
switch level {
|
||||
case 1:
|
||||
return &snappyL1{}
|
||||
case 2:
|
||||
return &snappyL2{snappyGen: snappyGen{cur: maxStoreBlockSize, prev: make([]byte, 0, maxStoreBlockSize)}}
|
||||
case 3:
|
||||
return &snappyL3{snappyGen: snappyGen{cur: maxStoreBlockSize, prev: make([]byte, 0, maxStoreBlockSize)}}
|
||||
case 4:
|
||||
return &snappyL4{snappyL3{snappyGen: snappyGen{cur: maxStoreBlockSize, prev: make([]byte, 0, maxStoreBlockSize)}}}
|
||||
default:
|
||||
panic("invalid level specified")
|
||||
}
|
||||
}
|
||||
|
||||
const (
|
||||
tableBits = 14 // Bits used in the table
|
||||
tableSize = 1 << tableBits // Size of the table
|
||||
tableMask = tableSize - 1 // Mask for table indices. Redundant, but can eliminate bounds checks.
|
||||
tableShift = 32 - tableBits // Right-shift to get the tableBits most significant bits of a uint32.
|
||||
baseMatchOffset = 1 // The smallest match offset
|
||||
baseMatchLength = 3 // The smallest match length per the RFC section 3.2.5
|
||||
maxMatchOffset = 1 << 15 // The largest match offset
|
||||
)
|
||||
|
||||
func load32(b []byte, i int) uint32 {
|
||||
b = b[i : i+4 : len(b)] // Help the compiler eliminate bounds checks on the next line.
|
||||
return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
|
||||
}
|
||||
|
||||
func load64(b []byte, i int) uint64 {
|
||||
b = b[i : i+8 : len(b)] // Help the compiler eliminate bounds checks on the next line.
|
||||
return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
|
||||
uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
|
||||
}
|
||||
|
||||
func hash(u uint32) uint32 {
|
||||
return (u * 0x1e35a7bd) >> tableShift
|
||||
}
|
||||
|
||||
// snappyL1 encapsulates level 1 compression
|
||||
type snappyL1 struct{}
|
||||
|
||||
func (e *snappyL1) Reset() {}
|
||||
|
||||
func (e *snappyL1) Encode(dst *tokens, src []byte) {
|
||||
const (
|
||||
inputMargin = 16 - 1
|
||||
minNonLiteralBlockSize = 1 + 1 + inputMargin
|
||||
)
|
||||
|
||||
// This check isn't in the Snappy implementation, but there, the caller
|
||||
// instead of the callee handles this case.
|
||||
if len(src) < minNonLiteralBlockSize {
|
||||
// We do not fill the token table.
|
||||
// This will be picked up by caller.
|
||||
dst.n = uint16(len(src))
|
||||
return
|
||||
}
|
||||
|
||||
// Initialize the hash table.
|
||||
//
|
||||
// The table element type is uint16, as s < sLimit and sLimit < len(src)
|
||||
// and len(src) <= maxStoreBlockSize and maxStoreBlockSize == 65535.
|
||||
var table [tableSize]uint16
|
||||
|
||||
// sLimit is when to stop looking for offset/length copies. The inputMargin
|
||||
// lets us use a fast path for emitLiteral in the main loop, while we are
|
||||
// looking for copies.
|
||||
sLimit := len(src) - inputMargin
|
||||
|
||||
// nextEmit is where in src the next emitLiteral should start from.
|
||||
nextEmit := 0
|
||||
|
||||
// The encoded form must start with a literal, as there are no previous
|
||||
// bytes to copy, so we start looking for hash matches at s == 1.
|
||||
s := 1
|
||||
nextHash := hash(load32(src, s))
|
||||
|
||||
for {
|
||||
// Copied from the C++ snappy implementation:
|
||||
//
|
||||
// Heuristic match skipping: If 32 bytes are scanned with no matches
|
||||
// found, start looking only at every other byte. If 32 more bytes are
|
||||
// scanned (or skipped), look at every third byte, etc.. When a match
|
||||
// is found, immediately go back to looking at every byte. This is a
|
||||
// small loss (~5% performance, ~0.1% density) for compressible data
|
||||
// due to more bookkeeping, but for non-compressible data (such as
|
||||
// JPEG) it's a huge win since the compressor quickly "realizes" the
|
||||
// data is incompressible and doesn't bother looking for matches
|
||||
// everywhere.
|
||||
//
|
||||
// The "skip" variable keeps track of how many bytes there are since
|
||||
// the last match; dividing it by 32 (ie. right-shifting by five) gives
|
||||
// the number of bytes to move ahead for each iteration.
|
||||
skip := 32
|
||||
|
||||
nextS := s
|
||||
candidate := 0
|
||||
for {
|
||||
s = nextS
|
||||
bytesBetweenHashLookups := skip >> 5
|
||||
nextS = s + bytesBetweenHashLookups
|
||||
skip += bytesBetweenHashLookups
|
||||
if nextS > sLimit {
|
||||
goto emitRemainder
|
||||
}
|
||||
candidate = int(table[nextHash&tableMask])
|
||||
table[nextHash&tableMask] = uint16(s)
|
||||
nextHash = hash(load32(src, nextS))
|
||||
if s-candidate <= maxMatchOffset && load32(src, s) == load32(src, candidate) {
|
||||
break
|
||||
}
|
||||
}
|
||||
|
||||
// A 4-byte match has been found. We'll later see if more than 4 bytes
|
||||
// match. But, prior to the match, src[nextEmit:s] are unmatched. Emit
|
||||
// them as literal bytes.
|
||||
emitLiteral(dst, src[nextEmit:s])
|
||||
|
||||
// Call emitCopy, and then see if another emitCopy could be our next
|
||||
// move. Repeat until we find no match for the input immediately after
|
||||
// what was consumed by the last emitCopy call.
|
||||
//
|
||||
// If we exit this loop normally then we need to call emitLiteral next,
|
||||
// though we don't yet know how big the literal will be. We handle that
|
||||
// by proceeding to the next iteration of the main loop. We also can
|
||||
// exit this loop via goto if we get close to exhausting the input.
|
||||
for {
|
||||
// Invariant: we have a 4-byte match at s, and no need to emit any
|
||||
// literal bytes prior to s.
|
||||
base := s
|
||||
|
||||
// Extend the 4-byte match as long as possible.
|
||||
//
|
||||
// This is an inlined version of Snappy's:
|
||||
// s = extendMatch(src, candidate+4, s+4)
|
||||
s += 4
|
||||
s1 := base + maxMatchLength
|
||||
if s1 > len(src) {
|
||||
s1 = len(src)
|
||||
}
|
||||
a := src[s:s1]
|
||||
b := src[candidate+4:]
|
||||
b = b[:len(a)]
|
||||
l := len(a)
|
||||
for i := range a {
|
||||
if a[i] != b[i] {
|
||||
l = i
|
||||
break
|
||||
}
|
||||
}
|
||||
s += l
|
||||
|
||||
// matchToken is flate's equivalent of Snappy's emitCopy.
|
||||
dst.tokens[dst.n] = matchToken(uint32(s-base-baseMatchLength), uint32(base-candidate-baseMatchOffset))
|
||||
dst.n++
|
||||
nextEmit = s
|
||||
if s >= sLimit {
|
||||
goto emitRemainder
|
||||
}
|
||||
|
||||
// We could immediately start working at s now, but to improve
|
||||
// compression we first update the hash table at s-1 and at s. If
|
||||
// another emitCopy is not our next move, also calculate nextHash
|
||||
// at s+1. At least on GOARCH=amd64, these three hash calculations
|
||||
// are faster as one load64 call (with some shifts) instead of
|
||||
// three load32 calls.
|
||||
x := load64(src, s-1)
|
||||
prevHash := hash(uint32(x >> 0))
|
||||
table[prevHash&tableMask] = uint16(s - 1)
|
||||
currHash := hash(uint32(x >> 8))
|
||||
candidate = int(table[currHash&tableMask])
|
||||
table[currHash&tableMask] = uint16(s)
|
||||
if s-candidate > maxMatchOffset || uint32(x>>8) != load32(src, candidate) {
|
||||
nextHash = hash(uint32(x >> 16))
|
||||
s++
|
||||
break
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
emitRemainder:
|
||||
if nextEmit < len(src) {
|
||||
emitLiteral(dst, src[nextEmit:])
|
||||
}
|
||||
}
|
||||
|
||||
type tableEntry struct {
|
||||
val uint32
|
||||
offset int32
|
||||
}
|
||||
|
||||
func load3232(b []byte, i int32) uint32 {
|
||||
b = b[i : i+4 : len(b)] // Help the compiler eliminate bounds checks on the next line.
|
||||
return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
|
||||
}
|
||||
|
||||
func load6432(b []byte, i int32) uint64 {
|
||||
b = b[i : i+8 : len(b)] // Help the compiler eliminate bounds checks on the next line.
|
||||
return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
|
||||
uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
|
||||
}
|
||||
|
||||
// snappyGen maintains the table for matches,
|
||||
// and the previous byte block for level 2.
|
||||
// This is the generic implementation.
|
||||
type snappyGen struct {
|
||||
prev []byte
|
||||
cur int32
|
||||
}
|
||||
|
||||
// snappyGen maintains the table for matches,
|
||||
// and the previous byte block for level 2.
|
||||
// This is the generic implementation.
|
||||
type snappyL2 struct {
|
||||
snappyGen
|
||||
table [tableSize]tableEntry
|
||||
}
|
||||
|
||||
// EncodeL2 uses a similar algorithm to level 1, but is capable
|
||||
// of matching across blocks giving better compression at a small slowdown.
|
||||
func (e *snappyL2) Encode(dst *tokens, src []byte) {
|
||||
const (
|
||||
inputMargin = 8 - 1
|
||||
minNonLiteralBlockSize = 1 + 1 + inputMargin
|
||||
)
|
||||
|
||||
// Protect against e.cur wraparound.
|
||||
if e.cur > 1<<30 {
|
||||
for i := range e.table[:] {
|
||||
e.table[i] = tableEntry{}
|
||||
}
|
||||
e.cur = maxStoreBlockSize
|
||||
}
|
||||
|
||||
// This check isn't in the Snappy implementation, but there, the caller
|
||||
// instead of the callee handles this case.
|
||||
if len(src) < minNonLiteralBlockSize {
|
||||
// We do not fill the token table.
|
||||
// This will be picked up by caller.
|
||||
dst.n = uint16(len(src))
|
||||
e.cur += maxStoreBlockSize
|
||||
e.prev = e.prev[:0]
|
||||
return
|
||||
}
|
||||
|
||||
// sLimit is when to stop looking for offset/length copies. The inputMargin
|
||||
// lets us use a fast path for emitLiteral in the main loop, while we are
|
||||
// looking for copies.
|
||||
sLimit := int32(len(src) - inputMargin)
|
||||
|
||||
// nextEmit is where in src the next emitLiteral should start from.
|
||||
nextEmit := int32(0)
|
||||
s := int32(0)
|
||||
cv := load3232(src, s)
|
||||
nextHash := hash(cv)
|
||||
|
||||
for {
|
||||
// Copied from the C++ snappy implementation:
|
||||
//
|
||||
// Heuristic match skipping: If 32 bytes are scanned with no matches
|
||||
// found, start looking only at every other byte. If 32 more bytes are
|
||||
// scanned (or skipped), look at every third byte, etc.. When a match
|
||||
// is found, immediately go back to looking at every byte. This is a
|
||||
// small loss (~5% performance, ~0.1% density) for compressible data
|
||||
// due to more bookkeeping, but for non-compressible data (such as
|
||||
// JPEG) it's a huge win since the compressor quickly "realizes" the
|
||||
// data is incompressible and doesn't bother looking for matches
|
||||
// everywhere.
|
||||
//
|
||||
// The "skip" variable keeps track of how many bytes there are since
|
||||
// the last match; dividing it by 32 (ie. right-shifting by five) gives
|
||||
// the number of bytes to move ahead for each iteration.
|
||||
skip := int32(32)
|
||||
|
||||
nextS := s
|
||||
var candidate tableEntry
|
||||
for {
|
||||
s = nextS
|
||||
bytesBetweenHashLookups := skip >> 5
|
||||
nextS = s + bytesBetweenHashLookups
|
||||
skip += bytesBetweenHashLookups
|
||||
if nextS > sLimit {
|
||||
goto emitRemainder
|
||||
}
|
||||
candidate = e.table[nextHash&tableMask]
|
||||
now := load3232(src, nextS)
|
||||
e.table[nextHash&tableMask] = tableEntry{offset: s + e.cur, val: cv}
|
||||
nextHash = hash(now)
|
||||
|
||||
offset := s - (candidate.offset - e.cur)
|
||||
if offset > maxMatchOffset || cv != candidate.val {
|
||||
// Out of range or not matched.
|
||||
cv = now
|
||||
continue
|
||||
}
|
||||
break
|
||||
}
|
||||
|
||||
// A 4-byte match has been found. We'll later see if more than 4 bytes
|
||||
// match. But, prior to the match, src[nextEmit:s] are unmatched. Emit
|
||||
// them as literal bytes.
|
||||
emitLiteral(dst, src[nextEmit:s])
|
||||
|
||||
// Call emitCopy, and then see if another emitCopy could be our next
|
||||
// move. Repeat until we find no match for the input immediately after
|
||||
// what was consumed by the last emitCopy call.
|
||||
//
|
||||
// If we exit this loop normally then we need to call emitLiteral next,
|
||||
// though we don't yet know how big the literal will be. We handle that
|
||||
// by proceeding to the next iteration of the main loop. We also can
|
||||
// exit this loop via goto if we get close to exhausting the input.
|
||||
for {
|
||||
// Invariant: we have a 4-byte match at s, and no need to emit any
|
||||
// literal bytes prior to s.
|
||||
|
||||
// Extend the 4-byte match as long as possible.
|
||||
//
|
||||
s += 4
|
||||
t := candidate.offset - e.cur + 4
|
||||
l := e.matchlen(s, t, src)
|
||||
|
||||
// matchToken is flate's equivalent of Snappy's emitCopy. (length,offset)
|
||||
dst.tokens[dst.n] = matchToken(uint32(l+4-baseMatchLength), uint32(s-t-baseMatchOffset))
|
||||
dst.n++
|
||||
s += l
|
||||
nextEmit = s
|
||||
if s >= sLimit {
|
||||
t += l
|
||||
// Index first pair after match end.
|
||||
if int(t+4) < len(src) && t > 0 {
|
||||
cv := load3232(src, t)
|
||||
e.table[hash(cv)&tableMask] = tableEntry{offset: t + e.cur, val: cv}
|
||||
}
|
||||
goto emitRemainder
|
||||
}
|
||||
|
||||
// We could immediately start working at s now, but to improve
|
||||
// compression we first update the hash table at s-1 and at s. If
|
||||
// another emitCopy is not our next move, also calculate nextHash
|
||||
// at s+1. At least on GOARCH=amd64, these three hash calculations
|
||||
// are faster as one load64 call (with some shifts) instead of
|
||||
// three load32 calls.
|
||||
x := load6432(src, s-1)
|
||||
prevHash := hash(uint32(x))
|
||||
e.table[prevHash&tableMask] = tableEntry{offset: e.cur + s - 1, val: uint32(x)}
|
||||
x >>= 8
|
||||
currHash := hash(uint32(x))
|
||||
candidate = e.table[currHash&tableMask]
|
||||
e.table[currHash&tableMask] = tableEntry{offset: e.cur + s, val: uint32(x)}
|
||||
|
||||
offset := s - (candidate.offset - e.cur)
|
||||
if offset > maxMatchOffset || uint32(x) != candidate.val {
|
||||
cv = uint32(x >> 8)
|
||||
nextHash = hash(cv)
|
||||
s++
|
||||
break
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
emitRemainder:
|
||||
if int(nextEmit) < len(src) {
|
||||
emitLiteral(dst, src[nextEmit:])
|
||||
}
|
||||
e.cur += int32(len(src))
|
||||
e.prev = e.prev[:len(src)]
|
||||
copy(e.prev, src)
|
||||
}
|
||||
|
||||
type tableEntryPrev struct {
|
||||
Cur tableEntry
|
||||
Prev tableEntry
|
||||
}
|
||||
|
||||
// snappyL3
|
||||
type snappyL3 struct {
|
||||
snappyGen
|
||||
table [tableSize]tableEntryPrev
|
||||
}
|
||||
|
||||
// Encode uses a similar algorithm to level 2, will check up to two candidates.
|
||||
func (e *snappyL3) Encode(dst *tokens, src []byte) {
|
||||
const (
|
||||
inputMargin = 8 - 1
|
||||
minNonLiteralBlockSize = 1 + 1 + inputMargin
|
||||
)
|
||||
|
||||
// Protect against e.cur wraparound.
|
||||
if e.cur > 1<<30 {
|
||||
for i := range e.table[:] {
|
||||
e.table[i] = tableEntryPrev{}
|
||||
}
|
||||
e.snappyGen = snappyGen{cur: maxStoreBlockSize, prev: e.prev[:0]}
|
||||
}
|
||||
|
||||
// This check isn't in the Snappy implementation, but there, the caller
|
||||
// instead of the callee handles this case.
|
||||
if len(src) < minNonLiteralBlockSize {
|
||||
// We do not fill the token table.
|
||||
// This will be picked up by caller.
|
||||
dst.n = uint16(len(src))
|
||||
e.cur += maxStoreBlockSize
|
||||
e.prev = e.prev[:0]
|
||||
return
|
||||
}
|
||||
|
||||
// sLimit is when to stop looking for offset/length copies. The inputMargin
|
||||
// lets us use a fast path for emitLiteral in the main loop, while we are
|
||||
// looking for copies.
|
||||
sLimit := int32(len(src) - inputMargin)
|
||||
|
||||
// nextEmit is where in src the next emitLiteral should start from.
|
||||
nextEmit := int32(0)
|
||||
s := int32(0)
|
||||
cv := load3232(src, s)
|
||||
nextHash := hash(cv)
|
||||
|
||||
for {
|
||||
// Copied from the C++ snappy implementation:
|
||||
//
|
||||
// Heuristic match skipping: If 32 bytes are scanned with no matches
|
||||
// found, start looking only at every other byte. If 32 more bytes are
|
||||
// scanned (or skipped), look at every third byte, etc.. When a match
|
||||
// is found, immediately go back to looking at every byte. This is a
|
||||
// small loss (~5% performance, ~0.1% density) for compressible data
|
||||
// due to more bookkeeping, but for non-compressible data (such as
|
||||
// JPEG) it's a huge win since the compressor quickly "realizes" the
|
||||
// data is incompressible and doesn't bother looking for matches
|
||||
// everywhere.
|
||||
//
|
||||
// The "skip" variable keeps track of how many bytes there are since
|
||||
// the last match; dividing it by 32 (ie. right-shifting by five) gives
|
||||
// the number of bytes to move ahead for each iteration.
|
||||
skip := int32(32)
|
||||
|
||||
nextS := s
|
||||
var candidate tableEntry
|
||||
for {
|
||||
s = nextS
|
||||
bytesBetweenHashLookups := skip >> 5
|
||||
nextS = s + bytesBetweenHashLookups
|
||||
skip += bytesBetweenHashLookups
|
||||
if nextS > sLimit {
|
||||
goto emitRemainder
|
||||
}
|
||||
candidates := e.table[nextHash&tableMask]
|
||||
now := load3232(src, nextS)
|
||||
e.table[nextHash&tableMask] = tableEntryPrev{Prev: candidates.Cur, Cur: tableEntry{offset: s + e.cur, val: cv}}
|
||||
nextHash = hash(now)
|
||||
|
||||
// Check both candidates
|
||||
candidate = candidates.Cur
|
||||
if cv == candidate.val {
|
||||
offset := s - (candidate.offset - e.cur)
|
||||
if offset <= maxMatchOffset {
|
||||
break
|
||||
}
|
||||
} else {
|
||||
// We only check if value mismatches.
|
||||
// Offset will always be invalid in other cases.
|
||||
candidate = candidates.Prev
|
||||
if cv == candidate.val {
|
||||
offset := s - (candidate.offset - e.cur)
|
||||
if offset <= maxMatchOffset {
|
||||
break
|
||||
}
|
||||
}
|
||||
}
|
||||
cv = now
|
||||
}
|
||||
|
||||
// A 4-byte match has been found. We'll later see if more than 4 bytes
|
||||
// match. But, prior to the match, src[nextEmit:s] are unmatched. Emit
|
||||
// them as literal bytes.
|
||||
emitLiteral(dst, src[nextEmit:s])
|
||||
|
||||
// Call emitCopy, and then see if another emitCopy could be our next
|
||||
// move. Repeat until we find no match for the input immediately after
|
||||
// what was consumed by the last emitCopy call.
|
||||
//
|
||||
// If we exit this loop normally then we need to call emitLiteral next,
|
||||
// though we don't yet know how big the literal will be. We handle that
|
||||
// by proceeding to the next iteration of the main loop. We also can
|
||||
// exit this loop via goto if we get close to exhausting the input.
|
||||
for {
|
||||
// Invariant: we have a 4-byte match at s, and no need to emit any
|
||||
// literal bytes prior to s.
|
||||
|
||||
// Extend the 4-byte match as long as possible.
|
||||
//
|
||||
s += 4
|
||||
t := candidate.offset - e.cur + 4
|
||||
l := e.matchlen(s, t, src)
|
||||
|
||||
// matchToken is flate's equivalent of Snappy's emitCopy. (length,offset)
|
||||
dst.tokens[dst.n] = matchToken(uint32(l+4-baseMatchLength), uint32(s-t-baseMatchOffset))
|
||||
dst.n++
|
||||
s += l
|
||||
nextEmit = s
|
||||
if s >= sLimit {
|
||||
t += l
|
||||
// Index first pair after match end.
|
||||
if int(t+4) < len(src) && t > 0 {
|
||||
cv := load3232(src, t)
|
||||
nextHash = hash(cv)
|
||||
e.table[nextHash&tableMask] = tableEntryPrev{
|
||||
Prev: e.table[nextHash&tableMask].Cur,
|
||||
Cur: tableEntry{offset: e.cur + t, val: cv},
|
||||
}
|
||||
}
|
||||
goto emitRemainder
|
||||
}
|
||||
|
||||
// We could immediately start working at s now, but to improve
|
||||
// compression we first update the hash table at s-3 to s. If
|
||||
// another emitCopy is not our next move, also calculate nextHash
|
||||
// at s+1. At least on GOARCH=amd64, these three hash calculations
|
||||
// are faster as one load64 call (with some shifts) instead of
|
||||
// three load32 calls.
|
||||
x := load6432(src, s-3)
|
||||
prevHash := hash(uint32(x))
|
||||
e.table[prevHash&tableMask] = tableEntryPrev{
|
||||
Prev: e.table[prevHash&tableMask].Cur,
|
||||
Cur: tableEntry{offset: e.cur + s - 3, val: uint32(x)},
|
||||
}
|
||||
x >>= 8
|
||||
prevHash = hash(uint32(x))
|
||||
|
||||
e.table[prevHash&tableMask] = tableEntryPrev{
|
||||
Prev: e.table[prevHash&tableMask].Cur,
|
||||
Cur: tableEntry{offset: e.cur + s - 2, val: uint32(x)},
|
||||
}
|
||||
x >>= 8
|
||||
prevHash = hash(uint32(x))
|
||||
|
||||
e.table[prevHash&tableMask] = tableEntryPrev{
|
||||
Prev: e.table[prevHash&tableMask].Cur,
|
||||
Cur: tableEntry{offset: e.cur + s - 1, val: uint32(x)},
|
||||
}
|
||||
x >>= 8
|
||||
currHash := hash(uint32(x))
|
||||
candidates := e.table[currHash&tableMask]
|
||||
cv = uint32(x)
|
||||
e.table[currHash&tableMask] = tableEntryPrev{
|
||||
Prev: candidates.Cur,
|
||||
Cur: tableEntry{offset: s + e.cur, val: cv},
|
||||
}
|
||||
|
||||
// Check both candidates
|
||||
candidate = candidates.Cur
|
||||
if cv == candidate.val {
|
||||
offset := s - (candidate.offset - e.cur)
|
||||
if offset <= maxMatchOffset {
|
||||
continue
|
||||
}
|
||||
} else {
|
||||
// We only check if value mismatches.
|
||||
// Offset will always be invalid in other cases.
|
||||
candidate = candidates.Prev
|
||||
if cv == candidate.val {
|
||||
offset := s - (candidate.offset - e.cur)
|
||||
if offset <= maxMatchOffset {
|
||||
continue
|
||||
}
|
||||
}
|
||||
}
|
||||
cv = uint32(x >> 8)
|
||||
nextHash = hash(cv)
|
||||
s++
|
||||
break
|
||||
}
|
||||
}
|
||||
|
||||
emitRemainder:
|
||||
if int(nextEmit) < len(src) {
|
||||
emitLiteral(dst, src[nextEmit:])
|
||||
}
|
||||
e.cur += int32(len(src))
|
||||
e.prev = e.prev[:len(src)]
|
||||
copy(e.prev, src)
|
||||
}
|
||||
|
||||
// snappyL4
|
||||
type snappyL4 struct {
|
||||
snappyL3
|
||||
}
|
||||
|
||||
// Encode uses a similar algorithm to level 3,
|
||||
// but will check up to two candidates if first isn't long enough.
|
||||
func (e *snappyL4) Encode(dst *tokens, src []byte) {
|
||||
const (
|
||||
inputMargin = 8 - 3
|
||||
minNonLiteralBlockSize = 1 + 1 + inputMargin
|
||||
matchLenGood = 12
|
||||
)
|
||||
|
||||
// Protect against e.cur wraparound.
|
||||
if e.cur > 1<<30 {
|
||||
for i := range e.table[:] {
|
||||
e.table[i] = tableEntryPrev{}
|
||||
}
|
||||
e.snappyGen = snappyGen{cur: maxStoreBlockSize, prev: e.prev[:0]}
|
||||
}
|
||||
|
||||
// This check isn't in the Snappy implementation, but there, the caller
|
||||
// instead of the callee handles this case.
|
||||
if len(src) < minNonLiteralBlockSize {
|
||||
// We do not fill the token table.
|
||||
// This will be picked up by caller.
|
||||
dst.n = uint16(len(src))
|
||||
e.cur += maxStoreBlockSize
|
||||
e.prev = e.prev[:0]
|
||||
return
|
||||
}
|
||||
|
||||
// sLimit is when to stop looking for offset/length copies. The inputMargin
|
||||
// lets us use a fast path for emitLiteral in the main loop, while we are
|
||||
// looking for copies.
|
||||
sLimit := int32(len(src) - inputMargin)
|
||||
|
||||
// nextEmit is where in src the next emitLiteral should start from.
|
||||
nextEmit := int32(0)
|
||||
s := int32(0)
|
||||
cv := load3232(src, s)
|
||||
nextHash := hash(cv)
|
||||
|
||||
for {
|
||||
// Copied from the C++ snappy implementation:
|
||||
//
|
||||
// Heuristic match skipping: If 32 bytes are scanned with no matches
|
||||
// found, start looking only at every other byte. If 32 more bytes are
|
||||
// scanned (or skipped), look at every third byte, etc.. When a match
|
||||
// is found, immediately go back to looking at every byte. This is a
|
||||
// small loss (~5% performance, ~0.1% density) for compressible data
|
||||
// due to more bookkeeping, but for non-compressible data (such as
|
||||
// JPEG) it's a huge win since the compressor quickly "realizes" the
|
||||
// data is incompressible and doesn't bother looking for matches
|
||||
// everywhere.
|
||||
//
|
||||
// The "skip" variable keeps track of how many bytes there are since
|
||||
// the last match; dividing it by 32 (ie. right-shifting by five) gives
|
||||
// the number of bytes to move ahead for each iteration.
|
||||
skip := int32(32)
|
||||
|
||||
nextS := s
|
||||
var candidate tableEntry
|
||||
var candidateAlt tableEntry
|
||||
for {
|
||||
s = nextS
|
||||
bytesBetweenHashLookups := skip >> 5
|
||||
nextS = s + bytesBetweenHashLookups
|
||||
skip += bytesBetweenHashLookups
|
||||
if nextS > sLimit {
|
||||
goto emitRemainder
|
||||
}
|
||||
candidates := e.table[nextHash&tableMask]
|
||||
now := load3232(src, nextS)
|
||||
e.table[nextHash&tableMask] = tableEntryPrev{Prev: candidates.Cur, Cur: tableEntry{offset: s + e.cur, val: cv}}
|
||||
nextHash = hash(now)
|
||||
|
||||
// Check both candidates
|
||||
candidate = candidates.Cur
|
||||
if cv == candidate.val {
|
||||
offset := s - (candidate.offset - e.cur)
|
||||
if offset < maxMatchOffset {
|
||||
offset = s - (candidates.Prev.offset - e.cur)
|
||||
if cv == candidates.Prev.val && offset < maxMatchOffset {
|
||||
candidateAlt = candidates.Prev
|
||||
}
|
||||
break
|
||||
}
|
||||
} else {
|
||||
// We only check if value mismatches.
|
||||
// Offset will always be invalid in other cases.
|
||||
candidate = candidates.Prev
|
||||
if cv == candidate.val {
|
||||
offset := s - (candidate.offset - e.cur)
|
||||
if offset < maxMatchOffset {
|
||||
break
|
||||
}
|
||||
}
|
||||
}
|
||||
cv = now
|
||||
}
|
||||
|
||||
// A 4-byte match has been found. We'll later see if more than 4 bytes
|
||||
// match. But, prior to the match, src[nextEmit:s] are unmatched. Emit
|
||||
// them as literal bytes.
|
||||
emitLiteral(dst, src[nextEmit:s])
|
||||
|
||||
// Call emitCopy, and then see if another emitCopy could be our next
|
||||
// move. Repeat until we find no match for the input immediately after
|
||||
// what was consumed by the last emitCopy call.
|
||||
//
|
||||
// If we exit this loop normally then we need to call emitLiteral next,
|
||||
// though we don't yet know how big the literal will be. We handle that
|
||||
// by proceeding to the next iteration of the main loop. We also can
|
||||
// exit this loop via goto if we get close to exhausting the input.
|
||||
for {
|
||||
// Invariant: we have a 4-byte match at s, and no need to emit any
|
||||
// literal bytes prior to s.
|
||||
|
||||
// Extend the 4-byte match as long as possible.
|
||||
//
|
||||
s += 4
|
||||
t := candidate.offset - e.cur + 4
|
||||
l := e.matchlen(s, t, src)
|
||||
// Try alternative candidate if match length < matchLenGood.
|
||||
if l < matchLenGood-4 && candidateAlt.offset != 0 {
|
||||
t2 := candidateAlt.offset - e.cur + 4
|
||||
l2 := e.matchlen(s, t2, src)
|
||||
if l2 > l {
|
||||
l = l2
|
||||
t = t2
|
||||
}
|
||||
}
|
||||
// matchToken is flate's equivalent of Snappy's emitCopy. (length,offset)
|
||||
dst.tokens[dst.n] = matchToken(uint32(l+4-baseMatchLength), uint32(s-t-baseMatchOffset))
|
||||
dst.n++
|
||||
s += l
|
||||
nextEmit = s
|
||||
if s >= sLimit {
|
||||
t += l
|
||||
// Index first pair after match end.
|
||||
if int(t+4) < len(src) && t > 0 {
|
||||
cv := load3232(src, t)
|
||||
nextHash = hash(cv)
|
||||
e.table[nextHash&tableMask] = tableEntryPrev{
|
||||
Prev: e.table[nextHash&tableMask].Cur,
|
||||
Cur: tableEntry{offset: e.cur + t, val: cv},
|
||||
}
|
||||
}
|
||||
goto emitRemainder
|
||||
}
|
||||
|
||||
// We could immediately start working at s now, but to improve
|
||||
// compression we first update the hash table at s-3 to s. If
|
||||
// another emitCopy is not our next move, also calculate nextHash
|
||||
// at s+1. At least on GOARCH=amd64, these three hash calculations
|
||||
// are faster as one load64 call (with some shifts) instead of
|
||||
// three load32 calls.
|
||||
x := load6432(src, s-3)
|
||||
prevHash := hash(uint32(x))
|
||||
e.table[prevHash&tableMask] = tableEntryPrev{
|
||||
Prev: e.table[prevHash&tableMask].Cur,
|
||||
Cur: tableEntry{offset: e.cur + s - 3, val: uint32(x)},
|
||||
}
|
||||
x >>= 8
|
||||
prevHash = hash(uint32(x))
|
||||
|
||||
e.table[prevHash&tableMask] = tableEntryPrev{
|
||||
Prev: e.table[prevHash&tableMask].Cur,
|
||||
Cur: tableEntry{offset: e.cur + s - 2, val: uint32(x)},
|
||||
}
|
||||
x >>= 8
|
||||
prevHash = hash(uint32(x))
|
||||
|
||||
e.table[prevHash&tableMask] = tableEntryPrev{
|
||||
Prev: e.table[prevHash&tableMask].Cur,
|
||||
Cur: tableEntry{offset: e.cur + s - 1, val: uint32(x)},
|
||||
}
|
||||
x >>= 8
|
||||
currHash := hash(uint32(x))
|
||||
candidates := e.table[currHash&tableMask]
|
||||
cv = uint32(x)
|
||||
e.table[currHash&tableMask] = tableEntryPrev{
|
||||
Prev: candidates.Cur,
|
||||
Cur: tableEntry{offset: s + e.cur, val: cv},
|
||||
}
|
||||
|
||||
// Check both candidates
|
||||
candidate = candidates.Cur
|
||||
candidateAlt = tableEntry{}
|
||||
if cv == candidate.val {
|
||||
offset := s - (candidate.offset - e.cur)
|
||||
if offset <= maxMatchOffset {
|
||||
offset = s - (candidates.Prev.offset - e.cur)
|
||||
if cv == candidates.Prev.val && offset <= maxMatchOffset {
|
||||
candidateAlt = candidates.Prev
|
||||
}
|
||||
continue
|
||||
}
|
||||
} else {
|
||||
// We only check if value mismatches.
|
||||
// Offset will always be invalid in other cases.
|
||||
candidate = candidates.Prev
|
||||
if cv == candidate.val {
|
||||
offset := s - (candidate.offset - e.cur)
|
||||
if offset <= maxMatchOffset {
|
||||
continue
|
||||
}
|
||||
}
|
||||
}
|
||||
cv = uint32(x >> 8)
|
||||
nextHash = hash(cv)
|
||||
s++
|
||||
break
|
||||
}
|
||||
}
|
||||
|
||||
emitRemainder:
|
||||
if int(nextEmit) < len(src) {
|
||||
emitLiteral(dst, src[nextEmit:])
|
||||
}
|
||||
e.cur += int32(len(src))
|
||||
e.prev = e.prev[:len(src)]
|
||||
copy(e.prev, src)
|
||||
}
|
||||
|
||||
func (e *snappyGen) matchlen(s, t int32, src []byte) int32 {
|
||||
s1 := int(s) + maxMatchLength - 4
|
||||
if s1 > len(src) {
|
||||
s1 = len(src)
|
||||
}
|
||||
|
||||
// If we are inside the current block
|
||||
if t >= 0 {
|
||||
b := src[t:]
|
||||
a := src[s:s1]
|
||||
b = b[:len(a)]
|
||||
// Extend the match to be as long as possible.
|
||||
for i := range a {
|
||||
if a[i] != b[i] {
|
||||
return int32(i)
|
||||
}
|
||||
}
|
||||
return int32(len(a))
|
||||
}
|
||||
|
||||
// We found a match in the previous block.
|
||||
tp := int32(len(e.prev)) + t
|
||||
if tp < 0 {
|
||||
return 0
|
||||
}
|
||||
|
||||
// Extend the match to be as long as possible.
|
||||
a := src[s:s1]
|
||||
b := e.prev[tp:]
|
||||
if len(b) > len(a) {
|
||||
b = b[:len(a)]
|
||||
}
|
||||
a = a[:len(b)]
|
||||
for i := range b {
|
||||
if a[i] != b[i] {
|
||||
return int32(i)
|
||||
}
|
||||
}
|
||||
|
||||
// If we reached our limit, we matched everything we are
|
||||
// allowed to in the previous block and we return.
|
||||
n := int32(len(b))
|
||||
if int(s+n) == s1 {
|
||||
return n
|
||||
}
|
||||
|
||||
// Continue looking for more matches in the current block.
|
||||
a = src[s+n : s1]
|
||||
b = src[:len(a)]
|
||||
for i := range a {
|
||||
if a[i] != b[i] {
|
||||
return int32(i) + n
|
||||
}
|
||||
}
|
||||
return int32(len(a)) + n
|
||||
}
|
||||
|
||||
// Reset the encoding table.
|
||||
func (e *snappyGen) Reset() {
|
||||
e.prev = e.prev[:0]
|
||||
e.cur += maxMatchOffset
|
||||
}
|
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-null-max.dyn.expect
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-null-max.dyn.expect
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-null-max.dyn.expect-noinput
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-null-max.dyn.expect-noinput
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-null-max.golden
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-null-max.golden
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-null-max.in
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-null-max.in
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-null-max.wb.expect
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-null-max.wb.expect
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-null-max.wb.expect-noinput
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-null-max.wb.expect-noinput
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-pi.dyn.expect
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-pi.dyn.expect
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-pi.dyn.expect-noinput
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-pi.dyn.expect-noinput
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-pi.golden
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-pi.golden
generated
vendored
Normal file
Binary file not shown.
1
vendor/github.com/klauspost/compress/flate/testdata/huffman-pi.in
generated
vendored
Normal file
1
vendor/github.com/klauspost/compress/flate/testdata/huffman-pi.in
generated
vendored
Normal file
@@ -0,0 +1 @@
|
||||
3.141592653589793238462643383279502884197169399375105820974944592307816406286208998628034825342117067982148086513282306647093844609550582231725359408128481117450284102701938521105559644622948954930381964428810975665933446128475648233786783165271201909145648566923460348610454326648213393607260249141273724587006606315588174881520920962829254091715364367892590360011330530548820466521384146951941511609433057270365759591953092186117381932611793105118548074462379962749567351885752724891227938183011949129833673362440656643086021394946395224737190702179860943702770539217176293176752384674818467669405132000568127145263560827785771342757789609173637178721468440901224953430146549585371050792279689258923542019956112129021960864034418159813629774771309960518707211349999998372978049951059731732816096318595024459455346908302642522308253344685035261931188171010003137838752886587533208381420617177669147303598253490428755468731159562863882353787593751957781857780532171226806613001927876611195909216420198938095257201065485863278865936153381827968230301952035301852968995773622599413891249721775283479131515574857242454150695950829533116861727855889075098381754637464939319255060400927701671139009848824012858361603563707660104710181942955596198946767837449448255379774726847104047534646208046684259069491293313677028989152104752162056966024058038150193511253382430035587640247496473263914199272604269922796782354781636009341721641219924586315030286182974555706749838505494588586926995690927210797509302955321165344987202755960236480665499119881834797753566369807426542527862551818417574672890977772793800081647060016145249192173217214772350141441973568548161361157352552133475741849468438523323907394143334547762416862518983569485562099219222184272550254256887671790494601653466804988627232791786085784383827967976681454100953883786360950680064225125205117392984896084128488626945604241965285022210661186306744278622039194945047123713786960956364371917287467764657573962413890865832645995813390478027590099465764078951269468398352595709825822620522489407726719478268482601476990902640136394437455305068203496252451749399651431429809190659250937221696461515709858387410597885959772975498930161753928468138268683868942774155991855925245953959431049972524680845987273644695848653836736222626099124608051243884390451244136549762780797715691435997700129616089441694868555848406353422072225828488648158456028506016842739452267467678895252138522549954666727823986456596116354886230577456498035593634568174324112515076069479451096596094025228879710893145669136867228748940560101503308617928680920874760917824938589009714909675985261365549781893129784821682998948722658804857564014270477555132379641451523746234364542858444795265867821051141354735739523113427166102135969536231442952484937187110145765403590279934403742007310578539062198387447808478489683321445713868751943506430218453191048481005370614680674919278191197939952061419663428754440643745123718192179998391015919561814675142691239748940907186494231961567945208095146550225231603881930142093762137855956638937787083039069792077346722182562599661501421503068038447734549202605414665925201497442850732518666002132434088190710486331734649651453905796268561005508106658796998163574736384052571459102897064140110971206280439039759515677157700420337869936007230558763176359421873125147120532928191826186125867321579198414848829164470609575270695722091756711672291098169091528017350671274858322287183520935396572512108357915136988209144421006751033467110314126711136990865851639831501970165151168517143765761835155650884909989859982387345528331635507647918535893226185489632132933089857064204675259070915481416549859461637180
|
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-pi.wb.expect
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-pi.wb.expect
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-pi.wb.expect-noinput
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-pi.wb.expect-noinput
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-1k.dyn.expect
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-1k.dyn.expect
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-1k.dyn.expect-noinput
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-1k.dyn.expect-noinput
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-1k.golden
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-1k.golden
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-1k.in
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-1k.in
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-1k.wb.expect
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-1k.wb.expect
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-1k.wb.expect-noinput
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-1k.wb.expect-noinput
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-limit.dyn.expect
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-limit.dyn.expect
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-limit.dyn.expect-noinput
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-limit.dyn.expect-noinput
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-limit.golden
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-limit.golden
generated
vendored
Normal file
Binary file not shown.
4
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-limit.in
generated
vendored
Normal file
4
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-limit.in
generated
vendored
Normal file
@@ -0,0 +1,4 @@
|
||||
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
|
||||
<EFBFBD><EFBFBD><EFBFBD>vH
|
||||
<EFBFBD><EFBFBD>%<25><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><17>ɷ<EFBFBD><C9B7><06>}<18><>><07><><EFBFBD>ls<6C><73><EFBFBD>m<EFBFBD>IGH<15><><EFBFBD><EFBFBD>1Y<31>4<EFBFBD>[<5B><> 0[|]o#<23>
|
||||
<EFBFBD>-#<23><><EFBFBD>ul<><6C><EFBFBD>pf<70><66>ٱ<EFBFBD>n<EFBFBD>Y<EFBFBD>ԀY<D480>w<EFBFBD>C8ɯ02<30> F=gn<67>r<EFBFBD>N!O<><4F><EFBFBD>{<04><><03><05>k<EFBFBD>*<2A>w(<28><>b<EFBFBD> <20><1F>kQC9/<2F><>lu><3E>5<EFBFBD>C.<2E><>u<EFBFBD><75><EFBFBD>
|
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-limit.wb.expect
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-limit.wb.expect
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-limit.wb.expect-noinput
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-limit.wb.expect-noinput
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-max.golden
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-max.golden
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-max.in
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-rand-max.in
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-shifts.dyn.expect
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-shifts.dyn.expect
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-shifts.dyn.expect-noinput
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-shifts.dyn.expect-noinput
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-shifts.golden
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-shifts.golden
generated
vendored
Normal file
Binary file not shown.
2
vendor/github.com/klauspost/compress/flate/testdata/huffman-shifts.in
generated
vendored
Normal file
2
vendor/github.com/klauspost/compress/flate/testdata/huffman-shifts.in
generated
vendored
Normal file
@@ -0,0 +1,2 @@
|
||||
101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010
|
||||
232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323232323
|
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-shifts.wb.expect
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-shifts.wb.expect
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-shifts.wb.expect-noinput
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-shifts.wb.expect-noinput
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-text-shift.dyn.expect
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-text-shift.dyn.expect
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-text-shift.dyn.expect-noinput
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-text-shift.dyn.expect-noinput
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-text-shift.golden
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-text-shift.golden
generated
vendored
Normal file
Binary file not shown.
14
vendor/github.com/klauspost/compress/flate/testdata/huffman-text-shift.in
generated
vendored
Normal file
14
vendor/github.com/klauspost/compress/flate/testdata/huffman-text-shift.in
generated
vendored
Normal file
@@ -0,0 +1,14 @@
|
||||
//Copyright2009ThGoAuthor.Allrightrrvd.
|
||||
//UofthiourccodigovrndbyBSD-tyl
|
||||
//licnthtcnbfoundinthLICENSEfil.
|
||||
|
||||
pckgmin
|
||||
|
||||
import"o"
|
||||
|
||||
funcmin(){
|
||||
vrb=mk([]byt,65535)
|
||||
f,_:=o.Crt("huffmn-null-mx.in")
|
||||
f.Writ(b)
|
||||
}
|
||||
ABCDEFGHIJKLMNOPQRSTUVXxyz!"#¤%&/?"
|
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-text-shift.wb.expect
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-text-shift.wb.expect
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-text-shift.wb.expect-noinput
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-text-shift.wb.expect-noinput
generated
vendored
Normal file
Binary file not shown.
1
vendor/github.com/klauspost/compress/flate/testdata/huffman-text.dyn.expect
generated
vendored
Normal file
1
vendor/github.com/klauspost/compress/flate/testdata/huffman-text.dyn.expect
generated
vendored
Normal file
@@ -0,0 +1 @@
|
||||
<1C>_K<5F>0<1C><><EFBFBD><05><0E><>`K<><4B>0Aasě)^<5E>H<EFBFBD><48><EFBFBD><EFBFBD><EFBFBD>Iɟb<><DFBB>_><3E>4
|
1
vendor/github.com/klauspost/compress/flate/testdata/huffman-text.dyn.expect-noinput
generated
vendored
Normal file
1
vendor/github.com/klauspost/compress/flate/testdata/huffman-text.dyn.expect-noinput
generated
vendored
Normal file
@@ -0,0 +1 @@
|
||||
<1C>_K<5F>0<1C><><EFBFBD><05><0E><>`K<><4B>0Aasě)^<5E>H<EFBFBD><48><EFBFBD><EFBFBD><EFBFBD>Iɟb<><DFBB>_><3E>4
|
3
vendor/github.com/klauspost/compress/flate/testdata/huffman-text.golden
generated
vendored
Normal file
3
vendor/github.com/klauspost/compress/flate/testdata/huffman-text.golden
generated
vendored
Normal file
@@ -0,0 +1,3 @@
|
||||
<04>AK<41>0<07><>x<>ß<EFBFBD>Z<EFBFBD><5A><EFBFBD><EFBFBD>LP<4C>a<EFBFBD>!<21>x<EFBFBD><78>AD<41><44>I<13>&#I<>E<EFBFBD><45><EFBFBD><EFBFBD><06>p]<5D>Lƿ<4C><C6BF><16>F<EFBFBD>p<><70> 1<>88<38>h<07><13>$<24><><EFBFBD>5S<35><53>- <09>F66!<21>)v<>.<2E><02>0<EFBFBD>Y<EFBFBD><59><1E><02><><EFBFBD><EFBFBD>&<26><> S<><53><EFBFBD>N|d<>2:<3A><>
|
||||
t<EFBFBD>|둍<><EB918D><EFBFBD>xz9<7A><39><EFBFBD><EFBFBD><EFBFBD><EFBFBD>骺<EFBFBD><04><><EFBFBD><EFBFBD>Ɏ<EFBFBD>3<><33>
|
||||
&&=<3D><0E><><EFBFBD><EFBFBD><EFBFBD>ô<EFBFBD>UD<55>=Fu<46><75><EFBFBD><EFBFBD>]<5D><>q<EFBFBD><71><EFBFBD><EFBFBD>UL+<2B><><17><><08>>FQY<51><59>LZ<4C><5A>o<EFBFBD><6F><EFBFBD>fTߵ<54>EŴ<45><C5B4>{<7B>Yʶb<CAB6>e<EFBFBD>
|
13
vendor/github.com/klauspost/compress/flate/testdata/huffman-text.in
generated
vendored
Normal file
13
vendor/github.com/klauspost/compress/flate/testdata/huffman-text.in
generated
vendored
Normal file
@@ -0,0 +1,13 @@
|
||||
// Copyright 2009 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package main
|
||||
|
||||
import "os"
|
||||
|
||||
func main() {
|
||||
var b = make([]byte, 65535)
|
||||
f, _ := os.Create("huffman-null-max.in")
|
||||
f.Write(b)
|
||||
}
|
1
vendor/github.com/klauspost/compress/flate/testdata/huffman-text.wb.expect
generated
vendored
Normal file
1
vendor/github.com/klauspost/compress/flate/testdata/huffman-text.wb.expect
generated
vendored
Normal file
@@ -0,0 +1 @@
|
||||
<1C>_K<5F>0<1C><><EFBFBD><05><0E><>`K<><4B>0Aasě)^<5E>H<EFBFBD><48><EFBFBD><EFBFBD><EFBFBD>Iɟb<><DFBB>_><3E>4
|
1
vendor/github.com/klauspost/compress/flate/testdata/huffman-text.wb.expect-noinput
generated
vendored
Normal file
1
vendor/github.com/klauspost/compress/flate/testdata/huffman-text.wb.expect-noinput
generated
vendored
Normal file
@@ -0,0 +1 @@
|
||||
<1C>_K<5F>0<1C><><EFBFBD><05><0E><>`K<><4B>0Aasě)^<5E>H<EFBFBD><48><EFBFBD><EFBFBD><EFBFBD>Iɟb<><DFBB>_><3E>4
|
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-zero.dyn.expect
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-zero.dyn.expect
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-zero.dyn.expect-noinput
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-zero.dyn.expect-noinput
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-zero.golden
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-zero.golden
generated
vendored
Normal file
Binary file not shown.
1
vendor/github.com/klauspost/compress/flate/testdata/huffman-zero.in
generated
vendored
Normal file
1
vendor/github.com/klauspost/compress/flate/testdata/huffman-zero.in
generated
vendored
Normal file
@@ -0,0 +1 @@
|
||||
00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
|
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-zero.wb.expect
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-zero.wb.expect
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-zero.wb.expect-noinput
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/huffman-zero.wb.expect-noinput
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/null-long-match.dyn.expect-noinput
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/null-long-match.dyn.expect-noinput
generated
vendored
Normal file
Binary file not shown.
BIN
vendor/github.com/klauspost/compress/flate/testdata/null-long-match.wb.expect-noinput
generated
vendored
Normal file
BIN
vendor/github.com/klauspost/compress/flate/testdata/null-long-match.wb.expect-noinput
generated
vendored
Normal file
Binary file not shown.
115
vendor/github.com/klauspost/compress/flate/token.go
generated
vendored
Normal file
115
vendor/github.com/klauspost/compress/flate/token.go
generated
vendored
Normal file
@@ -0,0 +1,115 @@
|
||||
// Copyright 2009 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package flate
|
||||
|
||||
import "fmt"
|
||||
|
||||
const (
|
||||
// 2 bits: type 0 = literal 1=EOF 2=Match 3=Unused
|
||||
// 8 bits: xlength = length - MIN_MATCH_LENGTH
|
||||
// 22 bits xoffset = offset - MIN_OFFSET_SIZE, or literal
|
||||
lengthShift = 22
|
||||
offsetMask = 1<<lengthShift - 1
|
||||
typeMask = 3 << 30
|
||||
literalType = 0 << 30
|
||||
matchType = 1 << 30
|
||||
)
|
||||
|
||||
// The length code for length X (MIN_MATCH_LENGTH <= X <= MAX_MATCH_LENGTH)
|
||||
// is lengthCodes[length - MIN_MATCH_LENGTH]
|
||||
var lengthCodes = [...]uint32{
|
||||
0, 1, 2, 3, 4, 5, 6, 7, 8, 8,
|
||||
9, 9, 10, 10, 11, 11, 12, 12, 12, 12,
|
||||
13, 13, 13, 13, 14, 14, 14, 14, 15, 15,
|
||||
15, 15, 16, 16, 16, 16, 16, 16, 16, 16,
|
||||
17, 17, 17, 17, 17, 17, 17, 17, 18, 18,
|
||||
18, 18, 18, 18, 18, 18, 19, 19, 19, 19,
|
||||
19, 19, 19, 19, 20, 20, 20, 20, 20, 20,
|
||||
20, 20, 20, 20, 20, 20, 20, 20, 20, 20,
|
||||
21, 21, 21, 21, 21, 21, 21, 21, 21, 21,
|
||||
21, 21, 21, 21, 21, 21, 22, 22, 22, 22,
|
||||
22, 22, 22, 22, 22, 22, 22, 22, 22, 22,
|
||||
22, 22, 23, 23, 23, 23, 23, 23, 23, 23,
|
||||
23, 23, 23, 23, 23, 23, 23, 23, 24, 24,
|
||||
24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
|
||||
24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
|
||||
24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
|
||||
25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
|
||||
25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
|
||||
25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
|
||||
25, 25, 26, 26, 26, 26, 26, 26, 26, 26,
|
||||
26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
|
||||
26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
|
||||
26, 26, 26, 26, 27, 27, 27, 27, 27, 27,
|
||||
27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
|
||||
27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
|
||||
27, 27, 27, 27, 27, 28,
|
||||
}
|
||||
|
||||
var offsetCodes = [...]uint32{
|
||||
0, 1, 2, 3, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7,
|
||||
8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9,
|
||||
10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
|
||||
11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
|
||||
12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
|
||||
12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
|
||||
13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,
|
||||
13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,
|
||||
14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
|
||||
14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
|
||||
14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
|
||||
14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
|
||||
15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
|
||||
15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
|
||||
15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
|
||||
15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
|
||||
}
|
||||
|
||||
type token uint32
|
||||
|
||||
type tokens struct {
|
||||
tokens [maxStoreBlockSize + 1]token
|
||||
n uint16 // Must be able to contain maxStoreBlockSize
|
||||
}
|
||||
|
||||
// Convert a literal into a literal token.
|
||||
func literalToken(literal uint32) token { return token(literalType + literal) }
|
||||
|
||||
// Convert a < xlength, xoffset > pair into a match token.
|
||||
func matchToken(xlength uint32, xoffset uint32) token {
|
||||
return token(matchType + xlength<<lengthShift + xoffset)
|
||||
}
|
||||
|
||||
func matchTokend(xlength uint32, xoffset uint32) token {
|
||||
if xlength > maxMatchLength || xoffset > maxMatchOffset {
|
||||
panic(fmt.Sprintf("Invalid match: len: %d, offset: %d\n", xlength, xoffset))
|
||||
return token(matchType)
|
||||
}
|
||||
return token(matchType + xlength<<lengthShift + xoffset)
|
||||
}
|
||||
|
||||
// Returns the type of a token
|
||||
func (t token) typ() uint32 { return uint32(t) & typeMask }
|
||||
|
||||
// Returns the literal of a literal token
|
||||
func (t token) literal() uint32 { return uint32(t - literalType) }
|
||||
|
||||
// Returns the extra offset of a match token
|
||||
func (t token) offset() uint32 { return uint32(t) & offsetMask }
|
||||
|
||||
func (t token) length() uint32 { return uint32((t - matchType) >> lengthShift) }
|
||||
|
||||
func lengthCode(len uint32) uint32 { return lengthCodes[len] }
|
||||
|
||||
// Returns the offset code corresponding to a specific offset
|
||||
func offsetCode(off uint32) uint32 {
|
||||
if off < uint32(len(offsetCodes)) {
|
||||
return offsetCodes[off]
|
||||
} else if off>>7 < uint32(len(offsetCodes)) {
|
||||
return offsetCodes[off>>7] + 14
|
||||
} else {
|
||||
return offsetCodes[off>>14] + 28
|
||||
}
|
||||
}
|
258
vendor/github.com/klauspost/compress/flate/writer_test.go
generated
vendored
Normal file
258
vendor/github.com/klauspost/compress/flate/writer_test.go
generated
vendored
Normal file
@@ -0,0 +1,258 @@
|
||||
// Copyright 2012 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package flate
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"fmt"
|
||||
"io"
|
||||
"io/ioutil"
|
||||
"math/rand"
|
||||
"runtime"
|
||||
"testing"
|
||||
)
|
||||
|
||||
func benchmarkEncoder(b *testing.B, testfile, level, n int) {
|
||||
b.StopTimer()
|
||||
b.SetBytes(int64(n))
|
||||
buf0, err := ioutil.ReadFile(testfiles[testfile])
|
||||
if err != nil {
|
||||
b.Fatal(err)
|
||||
}
|
||||
if len(buf0) == 0 {
|
||||
b.Fatalf("test file %q has no data", testfiles[testfile])
|
||||
}
|
||||
buf1 := make([]byte, n)
|
||||
for i := 0; i < n; i += len(buf0) {
|
||||
if len(buf0) > n-i {
|
||||
buf0 = buf0[:n-i]
|
||||
}
|
||||
copy(buf1[i:], buf0)
|
||||
}
|
||||
buf0 = nil
|
||||
runtime.GC()
|
||||
w, err := NewWriter(ioutil.Discard, level)
|
||||
b.StartTimer()
|
||||
for i := 0; i < b.N; i++ {
|
||||
w.Reset(ioutil.Discard)
|
||||
_, err = w.Write(buf1)
|
||||
if err != nil {
|
||||
b.Fatal(err)
|
||||
}
|
||||
err = w.Close()
|
||||
if err != nil {
|
||||
b.Fatal(err)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func BenchmarkEncodeDigitsConstant1e4(b *testing.B) { benchmarkEncoder(b, digits, constant, 1e4) }
|
||||
func BenchmarkEncodeDigitsConstant1e5(b *testing.B) { benchmarkEncoder(b, digits, constant, 1e5) }
|
||||
func BenchmarkEncodeDigitsConstant1e6(b *testing.B) { benchmarkEncoder(b, digits, constant, 1e6) }
|
||||
func BenchmarkEncodeDigitsSpeed1e4(b *testing.B) { benchmarkEncoder(b, digits, speed, 1e4) }
|
||||
func BenchmarkEncodeDigitsSpeed1e5(b *testing.B) { benchmarkEncoder(b, digits, speed, 1e5) }
|
||||
func BenchmarkEncodeDigitsSpeed1e6(b *testing.B) { benchmarkEncoder(b, digits, speed, 1e6) }
|
||||
func BenchmarkEncodeDigitsDefault1e4(b *testing.B) { benchmarkEncoder(b, digits, default_, 1e4) }
|
||||
func BenchmarkEncodeDigitsDefault1e5(b *testing.B) { benchmarkEncoder(b, digits, default_, 1e5) }
|
||||
func BenchmarkEncodeDigitsDefault1e6(b *testing.B) { benchmarkEncoder(b, digits, default_, 1e6) }
|
||||
func BenchmarkEncodeDigitsCompress1e4(b *testing.B) { benchmarkEncoder(b, digits, compress, 1e4) }
|
||||
func BenchmarkEncodeDigitsCompress1e5(b *testing.B) { benchmarkEncoder(b, digits, compress, 1e5) }
|
||||
func BenchmarkEncodeDigitsCompress1e6(b *testing.B) { benchmarkEncoder(b, digits, compress, 1e6) }
|
||||
func BenchmarkEncodeTwainConstant1e4(b *testing.B) { benchmarkEncoder(b, twain, constant, 1e4) }
|
||||
func BenchmarkEncodeTwainConstant1e5(b *testing.B) { benchmarkEncoder(b, twain, constant, 1e5) }
|
||||
func BenchmarkEncodeTwainConstant1e6(b *testing.B) { benchmarkEncoder(b, twain, constant, 1e6) }
|
||||
func BenchmarkEncodeTwainSpeed1e4(b *testing.B) { benchmarkEncoder(b, twain, speed, 1e4) }
|
||||
func BenchmarkEncodeTwainSpeed1e5(b *testing.B) { benchmarkEncoder(b, twain, speed, 1e5) }
|
||||
func BenchmarkEncodeTwainSpeed1e6(b *testing.B) { benchmarkEncoder(b, twain, speed, 1e6) }
|
||||
func BenchmarkEncodeTwainDefault1e4(b *testing.B) { benchmarkEncoder(b, twain, default_, 1e4) }
|
||||
func BenchmarkEncodeTwainDefault1e5(b *testing.B) { benchmarkEncoder(b, twain, default_, 1e5) }
|
||||
func BenchmarkEncodeTwainDefault1e6(b *testing.B) { benchmarkEncoder(b, twain, default_, 1e6) }
|
||||
func BenchmarkEncodeTwainCompress1e4(b *testing.B) { benchmarkEncoder(b, twain, compress, 1e4) }
|
||||
func BenchmarkEncodeTwainCompress1e5(b *testing.B) { benchmarkEncoder(b, twain, compress, 1e5) }
|
||||
func BenchmarkEncodeTwainCompress1e6(b *testing.B) { benchmarkEncoder(b, twain, compress, 1e6) }
|
||||
|
||||
// A writer that fails after N writes.
|
||||
type errorWriter struct {
|
||||
N int
|
||||
}
|
||||
|
||||
func (e *errorWriter) Write(b []byte) (int, error) {
|
||||
if e.N <= 0 {
|
||||
return 0, io.ErrClosedPipe
|
||||
}
|
||||
e.N--
|
||||
return len(b), nil
|
||||
}
|
||||
|
||||
// Test if errors from the underlying writer is passed upwards.
|
||||
func TestWriteError(t *testing.T) {
|
||||
buf := new(bytes.Buffer)
|
||||
n := 65536
|
||||
if !testing.Short() {
|
||||
n *= 4
|
||||
}
|
||||
for i := 0; i < n; i++ {
|
||||
fmt.Fprintf(buf, "asdasfasf%d%dfghfgujyut%dyutyu\n", i, i, i)
|
||||
}
|
||||
in := buf.Bytes()
|
||||
// We create our own buffer to control number of writes.
|
||||
copyBuf := make([]byte, 128)
|
||||
for l := 0; l < 10; l++ {
|
||||
for fail := 1; fail <= 256; fail *= 2 {
|
||||
// Fail after 'fail' writes
|
||||
ew := &errorWriter{N: fail}
|
||||
w, err := NewWriter(ew, l)
|
||||
if err != nil {
|
||||
t.Fatalf("NewWriter: level %d: %v", l, err)
|
||||
}
|
||||
n, err := copyBuffer(w, bytes.NewBuffer(in), copyBuf)
|
||||
if err == nil {
|
||||
t.Fatalf("Level %d: Expected an error, writer was %#v", l, ew)
|
||||
}
|
||||
n2, err := w.Write([]byte{1, 2, 2, 3, 4, 5})
|
||||
if n2 != 0 {
|
||||
t.Fatal("Level", l, "Expected 0 length write, got", n)
|
||||
}
|
||||
if err == nil {
|
||||
t.Fatal("Level", l, "Expected an error")
|
||||
}
|
||||
err = w.Flush()
|
||||
if err == nil {
|
||||
t.Fatal("Level", l, "Expected an error on flush")
|
||||
}
|
||||
err = w.Close()
|
||||
if err == nil {
|
||||
t.Fatal("Level", l, "Expected an error on close")
|
||||
}
|
||||
|
||||
w.Reset(ioutil.Discard)
|
||||
n2, err = w.Write([]byte{1, 2, 3, 4, 5, 6})
|
||||
if err != nil {
|
||||
t.Fatal("Level", l, "Got unexpected error after reset:", err)
|
||||
}
|
||||
if n2 == 0 {
|
||||
t.Fatal("Level", l, "Got 0 length write, expected > 0")
|
||||
}
|
||||
if testing.Short() {
|
||||
return
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestDeterministicL1(t *testing.T) { testDeterministic(1, t) }
|
||||
func TestDeterministicL2(t *testing.T) { testDeterministic(2, t) }
|
||||
func TestDeterministicL3(t *testing.T) { testDeterministic(3, t) }
|
||||
func TestDeterministicL4(t *testing.T) { testDeterministic(4, t) }
|
||||
func TestDeterministicL5(t *testing.T) { testDeterministic(5, t) }
|
||||
func TestDeterministicL6(t *testing.T) { testDeterministic(6, t) }
|
||||
func TestDeterministicL7(t *testing.T) { testDeterministic(7, t) }
|
||||
func TestDeterministicL8(t *testing.T) { testDeterministic(8, t) }
|
||||
func TestDeterministicL9(t *testing.T) { testDeterministic(9, t) }
|
||||
func TestDeterministicL0(t *testing.T) { testDeterministic(0, t) }
|
||||
func TestDeterministicLM2(t *testing.T) { testDeterministic(-2, t) }
|
||||
|
||||
func testDeterministic(i int, t *testing.T) {
|
||||
// Test so much we cross a good number of block boundaries.
|
||||
var length = maxStoreBlockSize*30 + 500
|
||||
if testing.Short() {
|
||||
length /= 10
|
||||
}
|
||||
|
||||
// Create a random, but compressible stream.
|
||||
rng := rand.New(rand.NewSource(1))
|
||||
t1 := make([]byte, length)
|
||||
for i := range t1 {
|
||||
t1[i] = byte(rng.Int63() & 7)
|
||||
}
|
||||
|
||||
// Do our first encode.
|
||||
var b1 bytes.Buffer
|
||||
br := bytes.NewBuffer(t1)
|
||||
w, err := NewWriter(&b1, i)
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
// Use a very small prime sized buffer.
|
||||
cbuf := make([]byte, 787)
|
||||
_, err = copyBuffer(w, br, cbuf)
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
w.Close()
|
||||
|
||||
// We choose a different buffer size,
|
||||
// bigger than a maximum block, and also a prime.
|
||||
var b2 bytes.Buffer
|
||||
cbuf = make([]byte, 81761)
|
||||
br2 := bytes.NewBuffer(t1)
|
||||
w2, err := NewWriter(&b2, i)
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
_, err = copyBuffer(w2, br2, cbuf)
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
w2.Close()
|
||||
|
||||
b1b := b1.Bytes()
|
||||
b2b := b2.Bytes()
|
||||
|
||||
if !bytes.Equal(b1b, b2b) {
|
||||
t.Errorf("level %d did not produce deterministic result, result mismatch, len(a) = %d, len(b) = %d", i, len(b1b), len(b2b))
|
||||
}
|
||||
|
||||
// Test using io.WriterTo interface.
|
||||
var b3 bytes.Buffer
|
||||
br = bytes.NewBuffer(t1)
|
||||
w, err = NewWriter(&b3, i)
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
_, err = br.WriteTo(w)
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
w.Close()
|
||||
|
||||
b3b := b3.Bytes()
|
||||
if !bytes.Equal(b1b, b3b) {
|
||||
t.Errorf("level %d (io.WriterTo) did not produce deterministic result, result mismatch, len(a) = %d, len(b) = %d", i, len(b1b), len(b3b))
|
||||
}
|
||||
}
|
||||
|
||||
// copyBuffer is a copy of io.CopyBuffer, since we want to support older go versions.
|
||||
// This is modified to never use io.WriterTo or io.ReaderFrom interfaces.
|
||||
func copyBuffer(dst io.Writer, src io.Reader, buf []byte) (written int64, err error) {
|
||||
if buf == nil {
|
||||
buf = make([]byte, 32*1024)
|
||||
}
|
||||
for {
|
||||
nr, er := src.Read(buf)
|
||||
if nr > 0 {
|
||||
nw, ew := dst.Write(buf[0:nr])
|
||||
if nw > 0 {
|
||||
written += int64(nw)
|
||||
}
|
||||
if ew != nil {
|
||||
err = ew
|
||||
break
|
||||
}
|
||||
if nr != nw {
|
||||
err = io.ErrShortWrite
|
||||
break
|
||||
}
|
||||
}
|
||||
if er == io.EOF {
|
||||
break
|
||||
}
|
||||
if er != nil {
|
||||
err = er
|
||||
break
|
||||
}
|
||||
}
|
||||
return written, err
|
||||
}
|
Reference in New Issue
Block a user