const int GZIP_HEADER_ID1 = 31;
const int GZIP_HEADER_ID2 = 139;
const int GZIP_HEADER_METHOD_DEFLATE = 8;
-const int GZIP_HEADER_SIZE = 10;
+const unsigned int GZIP_HEADER_SIZE = 10;
const int GZIP_HEADER_FEXTRA = 1 << 2;
const int GZIP_HEADER_FNAME = 1 << 3;
const int GZIP_HEADER_COMMENT = 1 << 4;