[libcamera-devel] [PATCH] utils: ipc: Initialise ThreadProxy

[Laurent Pinchart]

Hi Kieran,

Thank you for the patch.

On Wed, Aug 04, 2021 at 11:21:56AM +0100, Kieran Bingham wrote:
> The ThreadProxy IPA template does not implement a constructor and the
> default compiler generated constructor does not initialise the private
> ipa_ pointer.
> 
> Whilst this should not be expected to be used while uninitialised, it
> does get caught by static analysis for every IPA module constructed, so
> lets be clean and fix it.
> 
> Reported-by: Coverity CID=350116
> Reported-by: Coverity CID=350123
> Reported-by: Coverity CID=350140
> Reported-by: Coverity CID=350147
> Fixes: 7832e19a599e ("utils: ipc: add templates for code generation for IPC mechanism")
> Signed-off-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> ---
>  .../generators/libcamera_templates/module_ipa_proxy.h.tmpl   | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/utils/ipc/generators/libcamera_templates/module_ipa_proxy.h.tmpl b/utils/ipc/generators/libcamera_templates/module_ipa_proxy.h.tmpl
> index ae168548492c..c222f5f204df 100644
> --- a/utils/ipc/generators/libcamera_templates/module_ipa_proxy.h.tmpl
> +++ b/utils/ipc/generators/libcamera_templates/module_ipa_proxy.h.tmpl
> @@ -72,6 +72,11 @@ private:
>  	class ThreadProxy : public Object
>  	{
>  	public:
> +		ThreadProxy()
> +			: ipa_(nullptr)
> +		{
> +		}
> +
>  		void setIPA({{interface_name}} *ipa)
>  		{
>  			ipa_ = ipa;

Note that this doesn't fix a bug, as we always call setIPA() before
using ipa_. As it's easy to please coverity and there's no drawback
(this is clearly not a hot path), it's good to keep the warnings count
low.

Another option would be

diff --git a/utils/ipc/generators/libcamera_templates/module_ipa_proxy.h.tmpl b/utils/ipc/generators/libcamera_templates/module_ipa_proxy.h.tmpl
index ae168548492c..d535e0417433 100644
--- a/utils/ipc/generators/libcamera_templates/module_ipa_proxy.h.tmpl
+++ b/utils/ipc/generators/libcamera_templates/module_ipa_proxy.h.tmpl
@@ -102,7 +102,7 @@ private:
 {%- endfor %}

 	private:
-		{{interface_name}} *ipa_;
+		{{interface_name}} *ipa_ = nullptr;
 	};

 	Thread thread_;

I wonder if the constructor would still be inline in that case. It
likely doesn't matter much as it's very simple anyway. Either way,

Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

-- 
Regards,

Laurent Pinchart