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Diffstat (limited to 'vendor/github.com/klauspost/compress/flate/token.go')
-rw-r--r--vendor/github.com/klauspost/compress/flate/token.go27
1 files changed, 9 insertions, 18 deletions
diff --git a/vendor/github.com/klauspost/compress/flate/token.go b/vendor/github.com/klauspost/compress/flate/token.go
index 4f275ea61..141299b97 100644
--- a/vendor/github.com/klauspost/compress/flate/token.go
+++ b/vendor/github.com/klauspost/compress/flate/token.go
@@ -4,8 +4,6 @@
package flate
-import "fmt"
-
const (
// 2 bits: type 0 = literal 1=EOF 2=Match 3=Unused
// 8 bits: xlength = length - MIN_MATCH_LENGTH
@@ -19,7 +17,7 @@ const (
// The length code for length X (MIN_MATCH_LENGTH <= X <= MAX_MATCH_LENGTH)
// is lengthCodes[length - MIN_MATCH_LENGTH]
-var lengthCodes = [...]uint32{
+var lengthCodes = [256]uint8{
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,
@@ -48,7 +46,7 @@ var lengthCodes = [...]uint32{
27, 27, 27, 27, 27, 28,
}
-var offsetCodes = [...]uint32{
+var offsetCodes = [256]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,
@@ -82,34 +80,27 @@ 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) }
+func (t token) literal() uint8 { return uint8(t) }
// 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 (t token) length() uint8 { return uint8(t >> lengthShift) }
-func lengthCode(len uint32) uint32 { return lengthCodes[len] }
+// The code is never more than 8 bits, but is returned as uint32 for convenience.
+func lengthCode(len uint8) uint32 { return uint32(lengthCodes[len]) }
// Returns the offset code corresponding to a specific offset
func offsetCode(off uint32) uint32 {
if off < uint32(len(offsetCodes)) {
- return offsetCodes[off]
+ return offsetCodes[off&255]
} else if off>>7 < uint32(len(offsetCodes)) {
- return offsetCodes[off>>7] + 14
+ return offsetCodes[(off>>7)&255] + 14
} else {
- return offsetCodes[off>>14] + 28
+ return offsetCodes[(off>>14)&255] + 28
}
}