diff --git a/src/saveload/saveload.cpp b/src/saveload/saveload.cpp
index dc611adf26..c7abaf50dc 100644
--- a/src/saveload/saveload.cpp
+++ b/src/saveload/saveload.cpp
@@ -649,51 +649,24 @@ void SlWriteByte(byte b)
 	_sl.dumper->WriteByte(b);
 }
 
-static inline int SlReadUint16()
+/**
+ * Returns number of bytes read so far
+ * May only be called during a load/load check action
+ */
+size_t SlGetBytesRead()
 {
-	int x = SlReadByte() << 8;
-	return x | SlReadByte();
-}
-
-static inline uint32 SlReadUint32()
-{
-	uint32 x = SlReadUint16() << 16;
-	return x | SlReadUint16();
-}
-
-static inline uint64 SlReadUint64()
-{
-	uint32 x = SlReadUint32();
-	uint32 y = SlReadUint32();
-	return (uint64)x << 32 | y;
-}
-
-static inline void SlWriteUint16(uint16 v)
-{
-	SlWriteByte(GB(v, 8, 8));
-	SlWriteByte(GB(v, 0, 8));
-}
-
-static inline void SlWriteUint32(uint32 v)
-{
-	SlWriteUint16(GB(v, 16, 16));
-	SlWriteUint16(GB(v,  0, 16));
-}
-
-static inline void SlWriteUint64(uint64 x)
-{
-	SlWriteUint32((uint32)(x >> 32));
-	SlWriteUint32((uint32)x);
+	assert(_sl.action == SLA_LOAD || _sl.action == SLA_LOAD_CHECK);
+	return _sl.reader->GetSize();
 }
 
 /**
- * Read in bytes from the file/data structure but don't do
- * anything with them, discarding them in effect
- * @param length The amount of bytes that is being treated this way
+ * Returns number of bytes written so far
+ * May only be called during a save action
  */
-static inline void SlSkipBytes(size_t length)
+size_t SlGetBytesWritten()
 {
-	for (; length != 0; length--) SlReadByte();
+	assert(_sl.action == SLA_SAVE);
+	return _sl.dumper->GetSize();
 }
 
 /**
diff --git a/src/saveload/saveload.h b/src/saveload/saveload.h
index 9c1d9615f5..b0da631d97 100644
--- a/src/saveload/saveload.h
+++ b/src/saveload/saveload.h
@@ -568,6 +568,56 @@ size_t SlCalcObjLength(const void *object, const SaveLoad *sld);
 byte SlReadByte();
 void SlWriteByte(byte b);
 
+static inline int SlReadUint16()
+{
+	int x = SlReadByte() << 8;
+	return x | SlReadByte();
+}
+
+static inline uint32 SlReadUint32()
+{
+	uint32 x = SlReadUint16() << 16;
+	return x | SlReadUint16();
+}
+
+static inline uint64 SlReadUint64()
+{
+	uint32 x = SlReadUint32();
+	uint32 y = SlReadUint32();
+	return (uint64)x << 32 | y;
+}
+
+static inline void SlWriteUint16(uint16 v)
+{
+	SlWriteByte(GB(v, 8, 8));
+	SlWriteByte(GB(v, 0, 8));
+}
+
+static inline void SlWriteUint32(uint32 v)
+{
+	SlWriteUint16(GB(v, 16, 16));
+	SlWriteUint16(GB(v,  0, 16));
+}
+
+static inline void SlWriteUint64(uint64 x)
+{
+	SlWriteUint32((uint32)(x >> 32));
+	SlWriteUint32((uint32)x);
+}
+
+/**
+ * Read in bytes from the file/data structure but don't do
+ * anything with them, discarding them in effect
+ * @param length The amount of bytes that is being treated this way
+ */
+static inline void SlSkipBytes(size_t length)
+{
+	for (; length != 0; length--) SlReadByte();
+}
+
+size_t SlGetBytesRead();
+size_t SlGetBytesWritten();
+
 void SlGlobList(const SaveLoadGlobVarList *sldg);
 void SlArray(void *array, size_t length, VarType conv);
 void SlObject(void *object, const SaveLoad *sld);