From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lee Hambley Subject: Re: Fwd: ieee80211_radiotap_iterator_next return values Date: Fri, 10 May 2013 17:22:48 +0200 Message-ID: References: <1368192729.8390.17.camel@jlt4.sipsolutions.net> Mime-Version: 1.0 Content-Type: multipart/alternative; boundary=047d7b414c2e528a2804dc5ebda4 Return-path: In-Reply-To: Sender: radiotap-owner-sUITvd46vNxg9hUCZPvPmw@public.gmane.org To: radiotap-S783fYmB3Ccdnm+yROfE0A@public.gmane.org List-Id: radiotap@radiotap.org --047d7b414c2e528a2804dc5ebda4 Content-Type: text/plain; charset=UTF-8 To clarify, I'm using (at present) the implementation from http://airscan.googlecode.com/svn-history/r2/trunk/radiotap-parser.c - not being an expert in such things it looks like the use of le32_to_cpu is an indication that this is designed to be used in userspace, but still - the iteration function is still returning `1'. Lee Hambley -- http://lee.hambley.name/+49 (0) 170 298 5667 On 10 May 2013 16:40, Lee Hambley wrote: > > Hi Johannes, > > I hadn't even considered that, I'll have to go and have a look for the userspace implementation of those functions, I'd suppose that the ones I have pulled in are probably from the kernel if they are returning `1`. > > Are these functions included with any of the radiotap (tcpdump, libpcap in particular) codebases? Or something similar. > > Thanks, good to know I did manage to register myself for the list correctly! > > Lee Hambley > -- > http://lee.hambley.name/ > +49 (0) 170 298 5667 > > > On 10 May 2013 15:32, Johannes Berg wrote: >> >> On Fri, 2013-05-10 at 14:55 +0200, Lee Hambley wrote: >> >> > int ret = ieee80211_radiotap_iterator_init(&rti, rth, rth->it_len); >> > while(!ret) { >> > printf("Itteration: %d\n", count++); >> > ret = ieee80211_radiotap_iterator_next(&rti); >> >> > >> > There's limited scope for having screwed something up in that code, I >> > think, I'm confused by the `1' being returned from >> > `ieee80211_radiotap_iterator_init' which according to the >> > implenentation doesn't seem like an error condition in the >> > implementation http://lxr.free-electrons.com/source/net/wireless/radiotap.c#L95 >> >> I think you're confusing the userspace and Linux kernel implementation, >> though they're very similar. In any case, >> ieee80211_radiotap_iterator_next() cannot return 1, unless one of the >> error values is defined to -1 (it returns -EINVAL and a few others) >> >> johannes >> >> > --047d7b414c2e528a2804dc5ebda4 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable

To clarify, I'm using (at present) the implementation = from http://airscan.googlecode.com/svn-history/r2/trunk/radiotap-pars= er.c - not being an expert in such things it looks like the use of le32= _to_cpu is an indication that this is designed to be used in userspace, but= still - the iteration function is still returning `1'.

Lee Hambley
--
http://lee.ha= mbley.name/+49 (0) 170 298 5667

On 10 May 2013 16:40, Lee Ha= mbley <lee.hambley-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
> Hi Johannes,
>
> I hadn't even considered that= , I'll have to go and have a look for the userspace implementation of t= hose functions, I'd suppose that the ones I have pulled in are probably= from the kernel if they are returning `1`.
>
> Are these functions included with any of the radiotap (tcpdump= , libpcap in particular) codebases? Or something similar.
>
> T= hanks, good to know I did manage to register myself for the list correctly!=
>
> Lee Hambley
> --
> http://lee.hambley.name/
> +49 (0) 170 298 5667
>
= >
> On 10 May 2013 15:32, Johannes Berg <johannes-cdvu00un1VgdHxzADdlk8Q@public.gmane.org> wrote:
>>
>> On Fri, 2013-05-10 at 14:55 +0200, Lee Hambley wrote:<= br>>>
>> > int ret =3D ieee80211_radiotap_iterator_init(&= amp;rti, rth, rth->it_len);
>> > while(!ret) {
>> &= gt; =C2=A0 printf("Itteration: %d\n", count++);
>> > =C2=A0 ret =3D ieee80211_radiotap_iterator_next(&rti);>>
>> >
>> > There's limited scope for h= aving screwed something up in that code, I
>> > think, I'm = confused by the `1' being returned from
>> > `ieee80211_radiotap_iterator_init' which according to the=
>> > implenentation doesn't seem like an error condition i= n the
>> > implementation http://lxr.free-electrons.com/sourc= e/net/wireless/radiotap.c#L95
>>
>> I think you're confusing the userspace and Linux k= ernel implementation,
>> though they're very similar. In any c= ase,
>> ieee80211_radiotap_iterator_next() cannot return 1, unless= one of the
>> error values is defined to -1 (it returns -EINVAL and a few others= )
>>
>> johannes
>>
>>
>
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