Re: [PATCH 0/1] bitbake-whatchanged: print what is about to happen

[Robert Yang <liezhi.yang@windriver.com>]

On 08/08/2012 05:12 PM, Paul Eggleton wrote:
> On Wednesday 08 August 2012 11:40:14 Robert Yang wrote:
>> On 08/08/2012 05:01 AM, Richard Purdie wrote:
>>> On Tue, 2012-08-07 at 18:12 +0100, Paul Eggleton wrote:
>>>> A couple of other things:
>>>>
>>>> 1) We ought to be able to assume that TMPDIR is the same regardless of
>>>> the recipe specified; this avoids having to parse all of the recipes just
>>>> to get the value of this variable.
>>
>> I'm sorry, I don't understand what did you mean here. it seems that what
>> I did is the same as you said: Use "bitbake -e" to figure out the TMPDIR at
>> the beginning, then use it elsewhere.
>
> Sorry, I wasn't being very clear. If you specify the recipe with bitbake -e,
> bitbake has to go through a parse of the recipes (retrieving from the cache if
> available of course, but even that still takes a few seconds). I'm suggesting
> you don't specify the recipe as TMPDIR shouldn't be recipe-specific, and save
> quite a bit of time.
>
>>>> 2) I'm a little concerned with the general approach - is there no way of
>>>> avoiding having to copy and move around the stamps directory? It seems
>>>> a little risky if nothing else.
>>>
>>> I think adding a parameter to -S would be a good move for this, its
>>> something people likely want in conjunction with that.
>>
>> Yes, add a parameter to "bitbake -S recipe" would be the correct way, but
>> as far as I know, the "-S" is a bool option currently, it doesn't accept
>> an argument, I think that we have the following 2 solutions:
>>

Got it, thanks.

>> 1) Modify the "-S" to accept an argument, but this may break the the usage
>>      of the "bitbake -S", the currently usage is:
>>
>>      bitbake -S <recipe>
>>
>>      We may change it to:
>>
>>      bitbake -S <tmpdir>(or stampsdir) <recipe>
>>
>>      But it seems that it's not easy differentiate the argument behind "-S".
>
> I have to admit I'm not sure what -S is currently being used for; so it's hard
> for me to comment on what might get broken if we change this. I suspect it's
> not being used very much at all though.
>
>> 2) Use "TMPDIR(or STAMP)=<path> bitbake -S recipe", but we don't support it
>>      currently, but we can add an os.getenv("TMPDIR") in bitbake to achieve
>> it, the BB_TMPDIR or BB_STAMP would be better, but I'm not sure whether it
>> will cause other problems.
>>
>> I'd like to send a patch for 2) if you are OK with it.
>
> We already have a mechanism to allow through variables from the environment -
> BB_ENV_WHITELIST / BB_ENV_EXTRAWHITE, and we should make use of that in
> preference to os.getenv(). I think we would not want this change in stamp
> writing behaviour to take effect unless -S is being used though, which suggests
> it ought to be a new variable that is not checked unless -S has been specified.
>

Thank you very much, I will add a BB_DUMP_STAMP.

// Robert

> Cheers,
> Paul
>