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-rw-r--r--vendor/github.com/klauspost/compress/internal/snapref/encode_other.go28
1 files changed, 27 insertions, 1 deletions
diff --git a/vendor/github.com/klauspost/compress/internal/snapref/encode_other.go b/vendor/github.com/klauspost/compress/internal/snapref/encode_other.go
index 511bba65..05db94d3 100644
--- a/vendor/github.com/klauspost/compress/internal/snapref/encode_other.go
+++ b/vendor/github.com/klauspost/compress/internal/snapref/encode_other.go
@@ -18,6 +18,7 @@ func load64(b []byte, i int) uint64 {
// emitLiteral writes a literal chunk and returns the number of bytes written.
//
// It assumes that:
+//
// dst is long enough to hold the encoded bytes
// 1 <= len(lit) && len(lit) <= 65536
func emitLiteral(dst, lit []byte) int {
@@ -42,6 +43,7 @@ func emitLiteral(dst, lit []byte) int {
// emitCopy writes a copy chunk and returns the number of bytes written.
//
// It assumes that:
+//
// dst is long enough to hold the encoded bytes
// 1 <= offset && offset <= 65535
// 4 <= length && length <= 65535
@@ -89,6 +91,7 @@ func emitCopy(dst []byte, offset, length int) int {
// src[i:i+k-j] and src[j:k] have the same contents.
//
// It assumes that:
+//
// 0 <= i && i < j && j <= len(src)
func extendMatch(src []byte, i, j int) int {
for ; j < len(src) && src[i] == src[j]; i, j = i+1, j+1 {
@@ -100,13 +103,36 @@ func hash(u, shift uint32) uint32 {
return (u * 0x1e35a7bd) >> shift
}
+// EncodeBlockInto exposes encodeBlock but checks dst size.
+func EncodeBlockInto(dst, src []byte) (d int) {
+ if MaxEncodedLen(len(src)) > len(dst) {
+ return 0
+ }
+
+ // encodeBlock breaks on too big blocks, so split.
+ for len(src) > 0 {
+ p := src
+ src = nil
+ if len(p) > maxBlockSize {
+ p, src = p[:maxBlockSize], p[maxBlockSize:]
+ }
+ if len(p) < minNonLiteralBlockSize {
+ d += emitLiteral(dst[d:], p)
+ } else {
+ d += encodeBlock(dst[d:], p)
+ }
+ }
+ return d
+}
+
// encodeBlock encodes a non-empty src to a guaranteed-large-enough dst. It
// assumes that the varint-encoded length of the decompressed bytes has already
// been written.
//
// It also assumes that:
+//
// len(dst) >= MaxEncodedLen(len(src)) &&
-// minNonLiteralBlockSize <= len(src) && len(src) <= maxBlockSize
+// minNonLiteralBlockSize <= len(src) && len(src) <= maxBlockSize
func encodeBlock(dst, src []byte) (d int) {
// Initialize the hash table. Its size ranges from 1<<8 to 1<<14 inclusive.
// The table element type is uint16, as s < sLimit and sLimit < len(src)