|
Message-ID: <Ye8Dqm6lBUfCgAWf@pirotess> Date: Mon, 24 Jan 2022 20:53:14 +0100 From: Ismael Luceno <ismael@...ev.co.uk> To: musl@...ts.openwall.com Cc: Rich Felker <dalias@...c.org> Subject: Re: [PATCH v3 2/2] nftw: implement FTW_ACTIONRETVAL (GNU extension) On 24/Jan/2022 09:47, Dominique MARTINET wrote: > This didn't get much traction when I submitted one last year: > https://www.openwall.com/lists/musl/2021/03/26/1 > (and there were at least a couple other occurences I could find at the > time) Thanks for reviewing. I was unaware of your submission. > But given it keeps getting resubmitted I assume we can say that confirms > there's demand for it? <...> > > @@ -72,12 +72,19 @@ static int do_nftw(char *path, int (*fn)(const char *, const struct stat *, int, > > if (!fd_limit) close(dfd); > > } > > > > - if (!(flags & FTW_DEPTH) && (r=fn(path, &st, type, &lev))) > > - return r; > > + r = 0; > > + if (!(flags & FTW_DEPTH) && (r=fn(path, &st, type, &lev))) { > > + if ((flags & FTW_ACTIONRETVAL)) { > > + if (r == FTW_STOP) return FTW_STOP; > > + if (r == FTW_SKIP_SUBTREE) return 0; > > + /* other values are saved for when returning */ > > Hm, I'd naively think you would want to return immediately the other > values as well, so the else below is wrong? > But I didn't take long enough to check what e.g. a SKIP_SIBLINGS would > mean here, the construction just looks a bit odd to me. SKIP_SIBLINGS doesn't imply SKIP_SUBTREE, so must be saved and returned when finishing. > > @@ -120,10 +130,13 @@ static int do_nftw(char *path, int (*fn)(const char *, const struct stat *, int, > > } > > > > path[l] = 0; > > - if ((flags & FTW_DEPTH) && (r=fn(path, &st, type, &lev))) > > - return r; > > - > > - return 0; > > + if (flags & FTW_DEPTH) { > > + r = fn(path, &st, type, &lev); > > + /* ignore FTW_SKIP_SUBTREE (too late), the caller is broken */ > > + if ((flags & FTW_ACTIONRETVAL) && r == FTW_SKIP_SUBTREE) > > + return 0; > > IIRC the glibc implementation also ignores FTW_SKIP_SIBLINGS in that > case (nftw returns 0), I'm not sure how much of a 1-to-1 implementation > we want -- I had implemented my version through a black-box approach > with a client exercising all kind of different code paths as for a gnu > extension I'd assume glibc to be the reference. FTW_SKIP_SUBTREE makes no sense with FTW_DEPTH, but FTW_SKIP_SIBLINGS works with both.
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.