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-rw-r--r--vendor/github.com/klauspost/compress/flate/token.go115
1 files changed, 115 insertions, 0 deletions
diff --git a/vendor/github.com/klauspost/compress/flate/token.go b/vendor/github.com/klauspost/compress/flate/token.go
new file mode 100644
index 000000000..4f275ea61
--- /dev/null
+++ b/vendor/github.com/klauspost/compress/flate/token.go
@@ -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
+ }
+}