Re: [cocci] Searching for lock calls without unlocking (with SmPL)?

[Markus Elfring <Markus.Elfring@web.de>]

>>>>>      The one in the if is matching with the call closest to it,
>>>>
>>>> I interpret this hit as a false positive.
>>>> (The first lock call in the if branch is not the relevant companion call
>>>> from the function implementation.)
>>>>
>>>>
>>>>>                                                                 not the
>>>>> call at the beginning of the function.
>>>>
>>>> This is an essential requirement for the discussed source code search pattern,
>>>> isn't it?
>>>
>>> No.
>>
>> I hope still that a better common understanding can be achieved.
>>
>>
>>>      I don't understand why you think that.
>>
>> The source code search pattern tries to find a pair of lock calls.
>> Is the passed expression determined for the metavariable “y” after the second
>> lock call was found at the beginning of the function implementation?
> 
> I don't understand this at all.

Does this feedback indicate another communication problem?


>                                  Coccinelle doesn't care about the
> beginning of the function, unless you start the pattern with a function
> header or a ...

Where does the statement “action_lock(&blockage1);” appear in the implementation
of the function “my_action_test”?


> In all cases, Coccinelle looks at every node of the control-flow graph and
> tries to match the pattern there.  It doesn't care about beginning middle
> or end.

But should the analysis tool care more for selected function call combinations?

Would it be possible to determine that special control flow from an if branch
would be inappropriate according to the mentioned SmPL code?

Regards,
Markus