strperm.c revision 7c2fbfb345896881c631598ee3852ce9ce33fb07
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin/***********************************************************************
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* This software is part of the ast package *
7c2fbfb345896881c631598ee3852ce9ce33fb07April Chin* Copyright (c) 1985-2008 AT&T Intellectual Property *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* and is licensed under the *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* Common Public License, Version 1.0 *
7c2fbfb345896881c631598ee3852ce9ce33fb07April Chin* by AT&T Intellectual Property *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* A copy of the License is available at *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* Information and Software Systems Research *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* AT&T Research *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* Florham Park NJ *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* Glenn Fowler <gsf@research.att.com> *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* David Korn <dgk@research.att.com> *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin* Phong Vo <kpv@research.att.com> *
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin***********************************************************************/
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * Glenn Fowler
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * AT&T Research
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * apply file permission expression expr to perm
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * each expression term must match
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * [ugoa]*[-&+|^=]?[rwxst0-7]*
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * terms may be combined using ,
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * if non-null, e points to the first unrecognized char in expr
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin register int c;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin register int typ;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin register int who;
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin switch (c = *expr++)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin /*FALLTHROUGH*/
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin /*FALLTHROUGH*/
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin switch (c = *expr++)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin if (!S_ISDIR(perm) && !(perm & (S_IXUSR|S_IXGRP|S_IXOTH)))
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin /*FALLTHROUGH*/
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin /*FALLTHROUGH*/
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * propagate least restrictive to most restrictive
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin * if any execute then read => execute
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin switch (c)
da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968chin /*FALLTHROUGH*/