Shoeing

Signed-off-by: Shivansh Vij <shivanshvij@loopholelabs.io>

buffer.go

@@ -32,6 +32,13 @@ func NewBuffer() *Buffer {
 	}
 }
 
+func NewBufferSize(size int) *Buffer {
+	return &Buffer{
+		b:      make([]byte, size),
+		offset: 0,
+	}
+}
+
 func (buf *Buffer) Reset() {
 	buf.offset = 0
 }

decode.go

@@ -86,25 +86,44 @@ func decodeSlice(b []byte, kind Kind) ([]byte, uint32, error) {
 }
 
 func decodeBytes(b []byte, ret []byte) ([]byte, []byte, error) {
-	if len(b) > 0 && b[0] == BytesRawKind {
-		var size uint32
-		var err error
-		b, size, err = decodeUint32(b[1:])
-		if err != nil {
-			return b, nil, InvalidBytes
-		}
-		if len(b) > int(size)-1 {
-			if len(ret) < int(size) {
-				if ret == nil {
-					ret = make([]byte, size)
-					copy(ret, b[:size])
+	if len(b) > 3 && b[0] == BytesRawKind && b[1] == Uint32RawKind {
+		var size int
+		var offset int
+		cb := uint32(b[2])
+		if cb < continuation {
+			size = int(cb)
+			offset = 3
+		} else {
+			x := cb & (continuation - 1)
+			cb = uint32(b[3])
+			if cb < continuation {
+				size = int(x | (cb << 7))
+				offset = 4
+			} else {
+				x |= (cb & (continuation - 1)) << 7
+				cb = uint32(b[4])
+				if cb < continuation {
+					size = int(x | (cb << 14))
+					offset = 5
 				} else {
-					ret = append(ret[:0], b[:size]...)
+					x |= (cb & (continuation - 1)) << 14
+					cb = uint32(b[5])
+					if cb < continuation {
+						size = int(x | (cb << 21))
+						offset = 6
+					} else {
+						x |= (cb & (continuation - 1)) << 21
+						cb = uint32(b[6])
+						if cb < continuation {
+							size = int(x | (cb << 28))
+							offset = 7
+						}
+					}
 				}
-			} else {
-				copy(ret[0:], b[:size])
 			}
-			return b[size:], ret, nil
+		}
+		if len(b)-offset > size-1 {
+			return b[size+offset:], append(ret[:0], b[offset:size+offset]...), nil
 		}
 	}
 	return b, nil, InvalidBytes

encode.go

@@ -139,10 +139,53 @@ func EncodeBytes(b *Buffer, value []byte) {
 }
 
 func RawEncodeBytes(b *Buffer, value []byte) {
-	b.b[b.offset] = BytesRawKind
-	b.offset++
-	RawEncodeUint32(b, uint32(len(value)))
-	b.offset += copy(b.b[b.offset:], value)
+	castValue := uint32(len(value))
+	offset := b.offset
+	b.b[offset] = BytesRawKind
+	offset++
+	b.b[offset] = Uint32RawKind
+	offset++
+	if castValue < continuation {
+		b.b[offset] = byte(castValue)
+		offset++
+	} else {
+		b.b[offset] = byte(castValue&(continuation-1)) | continuation
+		offset++
+		castValue >>= 7
+		if castValue < continuation {
+			b.b[offset] = byte(castValue)
+			offset++
+		} else {
+			b.b[offset] = byte(castValue&(continuation-1)) | continuation
+			offset++
+			castValue >>= 7
+			if castValue < continuation {
+				b.b[offset] = byte(castValue)
+				offset++
+			} else {
+				b.b[offset] = byte(castValue&(continuation-1)) | continuation
+				offset++
+				castValue >>= 7
+				if castValue < continuation {
+					b.b[offset] = byte(castValue)
+					offset++
+				} else {
+					b.b[offset] = byte(castValue&(continuation-1)) | continuation
+					offset++
+					castValue >>= 7
+					if castValue < continuation {
+						b.b[offset] = byte(castValue)
+					} else {
+						b.b[offset] = byte(castValue&(continuation-1)) | continuation
+						offset++
+						b.b[offset] = byte(castValue >> 7)
+						offset++
+					}
+				}
+			}
+		}
+	}
+	b.offset = offset + copy(b.b[offset:], value)
 }
 
 func EncodeString(b *Buffer, value string) {