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Date: Fri, 21 Aug 2009 12:06:25 -0700
From: Rafael Laufer <rlaufer@cs.ucla.edu>
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Subject: Re: [PATCH] Implementation of the IEEE80211_RADIOTAP_RATE option
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Gábor Stefanik wrote:
> 2009/8/21 Rafael Laufer <rlaufer@cs.ucla.edu>:
>   
>> Gábor Stefanik wrote:
>>     
>>> Maybe a new IEEE80211_TX_CTL_ or IEEE80211_TX_RC_ flag will also be
>>> needed, so Radiotap can indicate whether rate_control_get_rate needs
>>> to be called.
>>>       
>> ok, I am resending the patch. I included a new flag called
>> IEEE80211_TX_CTL_RATE_RADIOTAP to indicate if the rate has
>> been set in the radiotap header. If not, then the rate control
>> algorithm is called.
>>     
>
> Isn't it easier to check whether we already have a rate configured?
> (info->control.rates[0].idx is set to an invalid value before the
> rate_control_get_rate call AFAIK, unless you set it in the radiotap
> decoding function before.)
>   

I guess it is also possible, but in that case you rely on the assumption
that the rate is invalid before rate_control_get_rate(). If in the
future this assumption does not hold, the code will break. If, however,
this is always gonna be true, I can change the code to use your
suggestion. Personally, I prefer to use another flag so that future
changes do not affect this code, but let me know what is best.

Rafael