Return smaller slices when compressing

Fixes #21
4kills · Dec 2, 2024 · 44664fd · 44664fd
1 parent be494b5
commit 44664fd
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Showing 2 changed files with 12 additions and 4 deletions.
diff --git a/native/compressor.go b/native/compressor.go
@@ -60,10 +60,14 @@ func (c *Compressor) Compress(in, out []byte, f compress) (int, []byte, error) {
 	if err == errorShortBuffer { // if still doesn't fit (shouldn't happen at all)
 		out = make([]byte, 1000+len(in)*2)
 		n, _, _ := c.compress(in, out, f)
-		return n, out[:n], errors.New("libdeflate: native: compressed data is much larger than uncompressed")
+		outSmallCap := make([]byte, len(out))
+		copy(outSmallCap, out)
+		return n, outSmallCap, errors.New("libdeflate: native: compressed data is much larger than uncompressed")
 	}
 
-	return n, out[:n], nil
+	outSmallCap := make([]byte, len(out))
+	copy(outSmallCap, out)
+	return n, outSmallCap, nil
 }
 
 func (c *Compressor) compress(in, out []byte, f compress) (int, []byte, error) {

diff --git a/v2/native/compressor.go b/v2/native/compressor.go
@@ -60,10 +60,14 @@ func (c *Compressor) Compress(in, out []byte, f compress) (int, []byte, error) {
 	if err == errorShortBuffer { // if still doesn't fit (shouldn't happen at all)
 		out = make([]byte, 1000+len(in)*2)
 		n, _, _ := c.compress(in, out, f)
-		return n, out[:n], errors.New("libdeflate: native: compressed data is much larger than uncompressed")
+		outSmallCap := make([]byte, len(out))
+		copy(outSmallCap, out)
+		return n, outSmallCap, errors.New("libdeflate: native: compressed data is much larger than uncompressed")
 	}
 
-	return n, out[:n], nil
+	outSmallCap := make([]byte, len(out))
+	copy(outSmallCap, out)
+	return n, outSmallCap, nil
 }
 
 func (c *Compressor) compress(in, out []byte, f compress) (int, []byte, error) {