From d9dbbb9a455f6bfc4e09d9f5f6c6c633f1b03c52 Mon Sep 17 00:00:00 2001 From: Jim Meyering Date: Sat, 7 Nov 2009 08:09:12 +0100 Subject: chcon, chgrp, chmod and chown now diagnose a directory cycle * lib/xfts.c (cycle_warning_required): New function. * lib/xfts.h: Declare it. * src/chown-core.c (change_file_owner): Diagnose a cycle. * src/chmod.c (process_file): Likewise. * src/chcon.c (process_file): Likewise. * NEWS (Bug fixes): Mention this. --- lib/xfts.c | 19 +++++++++++++++++++ lib/xfts.h | 4 ++++ 2 files changed, 23 insertions(+) (limited to 'lib') diff --git a/lib/xfts.c b/lib/xfts.c index 5994a5fef..9c46f6af5 100644 --- a/lib/xfts.c +++ b/lib/xfts.c @@ -61,3 +61,22 @@ xfts_open (char * const *argv, int options, return fts; } + +/* When fts_read returns FTS_DC to indicate a directory cycle, + it may or may not indicate a real problem. When a program like + chgrp performs a recursive traversal that requires traversing + symbolic links, it is *not* a problem. However, when invoked + with "-P -R", it deserves a warning. The fts_options member + records the options that control this aspect of fts's behavior, + so test that. */ +bool +cycle_warning_required (FTS const *fts, FTSENT const *ent) +{ +#define ISSET(Fts,Opt) ((Fts)->fts_options & (Opt)) + /* When dereferencing no symlinks, or when dereferencing only + those listed on the command line and we're not processing + a command-line argument, then a cycle is a serious problem. */ + return ((ISSET (fts, FTS_PHYSICAL) && !ISSET (fts, FTS_COMFOLLOW)) + || (ISSET (fts, FTS_PHYSICAL) && ISSET (fts, FTS_COMFOLLOW) + && ent->fts_level != FTS_ROOTLEVEL)); +} diff --git a/lib/xfts.h b/lib/xfts.h index 27ddb5d48..fc3ba9010 100644 --- a/lib/xfts.h +++ b/lib/xfts.h @@ -1,5 +1,9 @@ +#include #include "fts_.h" FTS * xfts_open (char * const *, int options, int (*) (const FTSENT **, const FTSENT **)); + +bool +cycle_warning_required (FTS const *fts, FTSENT const *ent); -- cgit v1.2.3-70-g09d2