saving extra cb info in savegames

src/bitstream.cpp

@@ -0,0 +1,58 @@
+#include "bitstream.h"
+
+// Returns 8 higher bits of s-bit integer x
+#define FIRST8(x, s) (((x) >> ((s) - 8)) & 0xFF)
+
+void BitOStream::WriteBytes(uint32 value, int amount)
+{
+	do {
+		v = (v << 8) | FIRST8(value, amount << 3);
+		f.push_back(FIRST8(v, c + 8));
+	} while (--amount);
+}
+
+void BitOStream::WriteBytes64(uint64 value, int amount)
+{
+	do {
+		v = (v << 8) | FIRST8(value, amount << 3);
+		f.push_back(FIRST8(v, c + 8));
+	} while (--amount);
+}
+
+/**
+ * Reserves memory for encoded data. Use to avoid reallocation of vector.
+ */
+void BitOStream::Reserve(int bytes)
+{
+	f.reserve(bytes);
+}
+
+/**
+ * Returns encoded data
+ */
+const u8vector &BitOStream::GetVector()
+{
+	return f;
+}
+
+/**
+ * Size of encoded data in bytes
+ */
+uint BitOStream::GetByteSize() const
+{
+	return f.size() + (c ? 1 : 0);
+}
+
+BitIStreamUnexpectedEnd _bit_i_stream_unexpected_end;
+
+uint32 BitIStream::ReadBytes(uint amount)
+{
+	uint32 res = 0;
+	while (amount--) {
+		if (i >= f.size()) {
+			throw _bit_i_stream_unexpected_end;
+		}
+		res = (res << 8) | f[i++];
+	}
+	return res;
+}