Adding modding folder with a hacked build.

modding/hacked/ss1/serial/PositioningEncoder.go

@@ -0,0 +1,57 @@
+package serial
+
+import (
+	"io"
+
+	"github.com/inkyblackness/hacked/ss1"
+)
+
+// PositioningEncoder is an Encoder with positioning capabilities.
+type PositioningEncoder struct {
+	Encoder
+
+	seeker io.Seeker
+}
+
+// NewPositioningEncoder returns an Encoder that also implements the Positioner interface.
+// The new Encoder starts with its zero position at the current position in the writer.
+func NewPositioningEncoder(target io.WriteSeeker) *PositioningEncoder {
+	return &PositioningEncoder{Encoder: Encoder{target: target}, seeker: target}
+}
+
+// SetCurPos changes the encoding position to the specified absolute offset.
+func (coder *PositioningEncoder) SetCurPos(offset uint32) {
+	if coder.firstError != nil {
+		return
+	}
+	_, coder.firstError = coder.seeker.Seek(int64(offset)-int64(coder.offset), io.SeekCurrent)
+	if coder.firstError != nil {
+		return
+	}
+	coder.offset = offset
+}
+
+const (
+	errInvalidWhence   ss1.StringError = "seek: invalid whence"
+	errSeekBeforeStart ss1.StringError = "seek: seeking before start"
+)
+
+// Seek repositions the current encoding offset.
+// This implementation does not support a whence value of io.SeekEnd.
+func (coder *PositioningEncoder) Seek(offset int64, whence int) (int64, error) {
+	var newPosition int64
+	switch whence {
+	default:
+		return int64(coder.offset), errInvalidWhence
+	case io.SeekStart:
+		newPosition = offset
+	case io.SeekCurrent:
+		newPosition = int64(coder.offset) + offset
+	}
+	if newPosition < 0 {
+		return int64(coder.offset), errSeekBeforeStart
+	}
+
+	coder.SetCurPos(uint32(newPosition))
+	return int64(coder.offset), coder.firstError
+}