fix file traversal bug in file utilities (on windows, not sure others)
fix file traversal bug in file utilities (on windows, not sure others)

glglwty/rDSN,qinzuoyan/rDSN,pandaworrior/rDSN,imzhenyu/rDSN,imzhenyu/rDSN,ykwd/rDSN,glglwty/rDSN,glglwty/rDSN,shengofsun/rDSN,lshmouse/rDSN,pandaworrior/rDSN,shengofsun/rDSN,ykwd/rDSN,pandaworrior/rDSN,pandaworrior/rDSN,lshmouse/rDSN,Microsoft/rDSN,ykwd/rDSN,Microsoft/rDSN,imzhenyu/rDSN,shengofsun/rDSN,Microsoft/rDSN,lshmouse/rDSN,shengofsun/rDSN,mcfatealan/rDSN,imzhenyu/rDSN,lshmouse/rDSN,ykwd/rDSN,qinzuoyan/rDSN,qinzuoyan/rDSN,imzhenyu/rDSN,glglwty/rDSN,mcfatealan/rDSN,goksyli/rDSN,qinzuoyan/rDSN,mcfatealan/rDSN,imzhenyu/rDSN,shengofsun/rDSN,glglwty/rDSN,goksyli/rDSN,goksyli/rDSN,pandaworrior/rDSN,lshmouse/rDSN,qinzuoyan/rDSN,Microsoft/rDSN,imzhenyu/rDSN,lshmouse/rDSN,qinzuoyan/rDSN,imzhenyu/rDSN,qinzuoyan/rDSN,shengofsun/rDSN,qinzuoyan/rDSN,Microsoft/rDSN,shengofsun/rDSN,ykwd/rDSN,mcfatealan/rDSN,lshmouse/rDSN,goksyli/rDSN,Microsoft/rDSN,Microsoft/rDSN,shengofsun/rDSN,Microsoft/rDSN,lshmouse/rDSN