Add xhttp transport

transport/v2rayxhttp/writer.go

@@ -0,0 +1,38 @@
+package xhttp
+
+import (
+	"github.com/sagernet/sing-box/common/xray/buf"
+	"github.com/sagernet/sing-box/common/xray/pipe"
+)
+
+// A wrapper around pipe that ensures the size limit is exactly honored.
+//
+// The MultiBuffer pipe accepts any single WriteMultiBuffer call even if that
+// single MultiBuffer exceeds the size limit, and then starts blocking on the
+// next WriteMultiBuffer call. This means that ReadMultiBuffer can return more
+// bytes than the size limit. We work around this by splitting a potentially
+// too large write up into multiple.
+type uploadWriter struct {
+	*pipe.Writer
+	maxLen int32
+}
+
+func (w uploadWriter) Write(b []byte) (int, error) {
+	/*
+		capacity := int(w.maxLen - w.Len())
+		if capacity > 0 && capacity < len(b) {
+			b = b[:capacity]
+		}
+	*/
+	buffer := buf.New()
+	n, err := buffer.Write(b)
+	if err != nil {
+		return 0, err
+	}
+
+	err = w.WriteMultiBuffer([]*buf.Buffer{buffer})
+	if err != nil {
+		return 0, err
+	}
+	return n, nil
+}