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-rw-r--r--vendor/github.com/golang/snappy/decode_other.go101
1 files changed, 101 insertions, 0 deletions
diff --git a/vendor/github.com/golang/snappy/decode_other.go b/vendor/github.com/golang/snappy/decode_other.go
new file mode 100644
index 0000000..8c9f204
--- /dev/null
+++ b/vendor/github.com/golang/snappy/decode_other.go
@@ -0,0 +1,101 @@
+// Copyright 2016 The Snappy-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 !amd64 appengine !gc noasm
+
+package snappy
+
+// decode writes the decoding of src to dst. It assumes that the varint-encoded
+// length of the decompressed bytes has already been read, and that len(dst)
+// equals that length.
+//
+// It returns 0 on success or a decodeErrCodeXxx error code on failure.
+func decode(dst, src []byte) int {
+ var d, s, offset, length int
+ for s < len(src) {
+ switch src[s] & 0x03 {
+ case tagLiteral:
+ x := uint32(src[s] >> 2)
+ switch {
+ case x < 60:
+ s++
+ case x == 60:
+ s += 2
+ if uint(s) > uint(len(src)) { // The uint conversions catch overflow from the previous line.
+ return decodeErrCodeCorrupt
+ }
+ x = uint32(src[s-1])
+ case x == 61:
+ s += 3
+ if uint(s) > uint(len(src)) { // The uint conversions catch overflow from the previous line.
+ return decodeErrCodeCorrupt
+ }
+ x = uint32(src[s-2]) | uint32(src[s-1])<<8
+ case x == 62:
+ s += 4
+ if uint(s) > uint(len(src)) { // The uint conversions catch overflow from the previous line.
+ return decodeErrCodeCorrupt
+ }
+ x = uint32(src[s-3]) | uint32(src[s-2])<<8 | uint32(src[s-1])<<16
+ case x == 63:
+ s += 5
+ if uint(s) > uint(len(src)) { // The uint conversions catch overflow from the previous line.
+ return decodeErrCodeCorrupt
+ }
+ x = uint32(src[s-4]) | uint32(src[s-3])<<8 | uint32(src[s-2])<<16 | uint32(src[s-1])<<24
+ }
+ length = int(x) + 1
+ if length <= 0 {
+ return decodeErrCodeUnsupportedLiteralLength
+ }
+ if length > len(dst)-d || length > len(src)-s {
+ return decodeErrCodeCorrupt
+ }
+ copy(dst[d:], src[s:s+length])
+ d += length
+ s += length
+ continue
+
+ case tagCopy1:
+ s += 2
+ if uint(s) > uint(len(src)) { // The uint conversions catch overflow from the previous line.
+ return decodeErrCodeCorrupt
+ }
+ length = 4 + int(src[s-2])>>2&0x7
+ offset = int(uint32(src[s-2])&0xe0<<3 | uint32(src[s-1]))
+
+ case tagCopy2:
+ s += 3
+ if uint(s) > uint(len(src)) { // The uint conversions catch overflow from the previous line.
+ return decodeErrCodeCorrupt
+ }
+ length = 1 + int(src[s-3])>>2
+ offset = int(uint32(src[s-2]) | uint32(src[s-1])<<8)
+
+ case tagCopy4:
+ s += 5
+ if uint(s) > uint(len(src)) { // The uint conversions catch overflow from the previous line.
+ return decodeErrCodeCorrupt
+ }
+ length = 1 + int(src[s-5])>>2
+ offset = int(uint32(src[s-4]) | uint32(src[s-3])<<8 | uint32(src[s-2])<<16 | uint32(src[s-1])<<24)
+ }
+
+ if offset <= 0 || d < offset || length > len(dst)-d {
+ return decodeErrCodeCorrupt
+ }
+ // Copy from an earlier sub-slice of dst to a later sub-slice. Unlike
+ // the built-in copy function, this byte-by-byte copy always runs
+ // forwards, even if the slices overlap. Conceptually, this is:
+ //
+ // d += forwardCopy(dst[d:d+length], dst[d-offset:])
+ for end := d + length; d != end; d++ {
+ dst[d] = dst[d-offset]
+ }
+ }
+ if d != len(dst) {
+ return decodeErrCodeCorrupt
+ }
+ return 0
+}