Date: Mon, 02 Aug 1999 12:38:40 -0700 From: Mike Smith <mike@smith.net.au> To: Alfred Perlstein <bright@rush.net> Cc: hackers@freebsd.org Subject: Re: confusion about nfsm_srvmtofh bad behavior? Message-ID: <199908021938.MAA00862@dingo.cdrom.com> In-Reply-To: Your message of "Mon, 02 Aug 1999 07:18:36 EDT." <Pine.BSF.3.96.990802064748.20420k-100000@cygnus.rush.net>
next in thread | previous in thread | raw e-mail | index | archive | help
>
> ok:
>
> #define nfsm_srvmtofh(f) \
> { int fhlen = NFSX_V3FH; \
> if (nfsd->nd_flag & ND_NFSV3) { \
> nfsm_dissect(tl, u_int32_t *, NFSX_UNSIGNED); \
> fhlen = fxdr_unsigned(int, *tl); \
> if (fhlen == 0) { \
> bzero((caddr_t)(f), NFSX_V3FH); \
> } else if (fhlen != NFSX_V3FH) { \
> error = EBADRPC; \
> nfsm_reply(0); \
> } \
> } \
> if (fhlen != 0) { \
> nfsm_dissect(tl, u_int32_t *, NFSX_V3FH); \
> bcopy((caddr_t)tl, (caddr_t)(f), NFSX_V3FH); \
> if ((nfsd->nd_flag & ND_NFSV3) == 0) \
> nfsm_adv(NFSX_V2FH - NFSX_V3FH); \
> } \
> }
>
> notice the bcopy? i don't really understand why we always
> seem to copy 64 bytes (NFSX_V3FH), isn't this a bug?
Yeah, you could probably rewrite as:
#define nfsm_srvmtofh(f) \
{ int fhlen; \
if (nfsd->nd_flag & ND_NFSV3) { \
nfsm_dissect(tl, u_int32_t *, NFSX_UNSIGNED); \
fhlen = fxdr_unsigned(int, *tl); \
if (fhlen == 0) { \
bzero((caddr_t)(f), NFSX_V3FH); \
} else if (fhlen != NFSX_V3FH) { \
error = EBADRPC; \
nfsm_reply(0); \
} else { \
nfsm_dissect(tl, u_int32_t *, NFSX_V3FH); \
bcopy((caddr_t)tl, (caddr_t)(f), NFSX_V3FH); \
}\
} else {
nfsm_dissect(tl, u_int32_t *, NFSX_V2FH); \
bcopy((caddr_t)tl, (caddr_t)(f), NFSX_V2FH); \
} \
}
which avoids using fhlen as an argument to anything (speed) and limits
the bcopy size appropriately by protocol.
--
\\ The mind's the standard \\ Mike Smith
\\ of the man. \\ msmith@freebsd.org
\\ -- Joseph Merrick \\ msmith@cdrom.com
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199908021938.MAA00862>