<pre>
Hi Laurent, Kieran,

Thank you.
I will add another patch to check the isValid() condition in ::create() itself.

Suhrid.


-----Original Message-----
From: Kieran Bingham <kieran.bingham@ideasonboard.com>
Sent: Monday, February 27, 2023 3:25 AM
To: Laurent Pinchart <laurent.pinchart@ideasonboard.com>; Laurent Pinchart via libcamera-devel <libcamera-devel@lists.libcamera.org>; Umang Jain <umang.jain@ideasonboard.com>
Cc: Suhrid Subramaniam <Suhrid.Subramaniam@mediatek.com>; libcamera-devel@lists.libcamera.org
Subject: Re: [libcamera-devel] libcamera: pipeline: simple: Check if converter_ is a nullptr

Quoting Laurent Pinchart via libcamera-devel (2023-02-26 15:41:36)
> On Fri, Feb 24, 2023 at 11:52:35AM +0530, Umang Jain via libcamera-devel wrote:
> > Hi Suhrid,
> >
> > Thank you for the patch.
> >
> > On 2/24/23 2:17 AM, Suhrid Subramaniam via libcamera-devel wrote:
> > > - If no converter is found, converter_ becomes a nullptr and
> > > !converter_->isValid() causes a segmentation fault.
> > > - Avoid this by checking if converter_ is a nullptr.
> > >
> > > Signed-off-by: Suhrid Subramaniam
> > > <suhrid.subramaniam@mediatek.com>
> > > ---
> > > src/libcamera/pipeline/simple/simple.cpp | 2 +-
> > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/src/libcamera/pipeline/simple/simple.cpp
> > > b/src/libcamera/pipeline/simple/simple.cpp
> > > index 24ded4db..2423ec10 100644
> > > --- a/src/libcamera/pipeline/simple/simple.cpp
> > > +++ b/src/libcamera/pipeline/simple/simple.cpp
> > > @@ -493,7 +493,7 @@ int SimpleCameraData::init()
> > > MediaDevice *converter = pipe->converter();
> > > if (converter) {
> > > converter_ = ConverterFactoryBase::create(converter);
> > > - if (!converter_->isValid()) {
> > > + if (!converter_) {
> >
> > it seems this change will drop the validity check so maybe :
> >         if (!converter_ && converter_->isValid()) {
> >
> > The error message below might be need to get tweaked a bit.
> >
> > On the other hand, I wonder if ConverterFactoryBase::create() should
> > be allowed? to return a non-valid converter pointer or not.
>
> I don't see a use case for that, so I'd rather check for !valid in
> ::create() and return nullptr in that case.

Yup - that answers my question. If we don't use isValid() it should be dropped.

But if it's removed here, but should be kept, please add it into ::create(). Probably as a patch preceeding this one.

--
Kieran


>
> > > LOG(SimplePipeline, Warning)
> > > << "Failed to create converter, disabling format conversion";
> > > converter_.reset();
>
> --
> Regards,
>
> Laurent Pinchart

</pre><!--type:text--><!--{--><pre>************* MEDIATEK Confidentiality Notice ********************
The information contained in this e-mail message (including any 
attachments) may be confidential, proprietary, privileged, or otherwise
exempt from disclosure under applicable laws. It is intended to be 
conveyed only to the designated recipient(s). Any use, dissemination, 
distribution, printing, retaining or copying of this e-mail (including its 
attachments) by unintended recipient(s) is strictly prohibited and may 
be unlawful. If you are not an intended recipient of this e-mail, or believe 
that you have received this e-mail in error, please notify the sender 
immediately (by replying to this e-mail), delete any and all copies of 
this e-mail (including any attachments) from your system, and do not
disclose the content of this e-mail to any other person. Thank you!
</pre><!--}-->