Re: [edk2-devel] [PATCH v1 2/2] MdeModulePkg/Bus/Usb/UsbMouseDxe: Fix MISSING_BREAK Coverity issues

["Leif Lindholm" <quic_llindhol@quicinc.com>]

On Wed, Oct 04, 2023 at 18:46:58 +0000, Michael D Kinney wrote:
> I do not prefer special comments for one static analyzer.
> 
> Is there an alternative design/implementation of this code
> to make it more readable and not trigger any static analysis
> false positives?

Not the tidiest, but could rewrite as:

    case 1:
    case 2:
    	 if (HidItem->Size == 1) {
	   <1 block>
	 }
	 <2 block>

That way we're making the code more expressive rather than keeping it
convoluted and adding a comment saying "code is convoluted".

Regards,

Leif

> > -----Original Message-----
> > From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Ranbir
> > Singh
> > Sent: Tuesday, October 3, 2023 10:48 PM
> > To: devel@edk2.groups.io; rsingh@ventanamicro.com
> > Cc: Wu, Hao A <hao.a.wu@intel.com>; Ni, Ray <ray.ni@intel.com>;
> > Veeresh Sangolli <veeresh.sangolli@dellteam.com>
> > Subject: [edk2-devel] [PATCH v1 2/2] MdeModulePkg/Bus/Usb/UsbMouseDxe:
> > Fix MISSING_BREAK Coverity issues
> > 
> > From: Ranbir Singh <Ranbir.Singh3@Dell.com>
> > 
> > The function GetNextHidItem has a switch-case code in which the
> > case 1: falls through to case 2: and then case 2: falls through
> > to case 3: in the block.
> > 
> > While this may be intentional, it is not evident to any general
> > code reader as well as any static analyzer tool. Just adding
> > 
> >     // No break; here as this is an intentional fallthrough.
> > 
> > as comment in between makes a reader as well as Coverity happy.
> > 
> > REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4222
> > 
> > Cc: Hao A Wu <hao.a.wu@intel.com>
> > Cc: Ray Ni <ray.ni@intel.com>
> > Co-authored-by: Veeresh Sangolli <veeresh.sangolli@dellteam.com>
> > Signed-off-by: Ranbir Singh <Ranbir.Singh3@Dell.com>
> > Signed-off-by: Ranbir Singh <rsingh@ventanamicro.com>
> > ---
> >  MdeModulePkg/Bus/Usb/UsbMouseDxe/MouseHid.c | 8 ++++++++
> >  1 file changed, 8 insertions(+)
> > 
> > diff --git a/MdeModulePkg/Bus/Usb/UsbMouseDxe/MouseHid.c
> > b/MdeModulePkg/Bus/Usb/UsbMouseDxe/MouseHid.c
> > index acc19acd98e0..bc9a4824208b 100644
> > --- a/MdeModulePkg/Bus/Usb/UsbMouseDxe/MouseHid.c
> > +++ b/MdeModulePkg/Bus/Usb/UsbMouseDxe/MouseHid.c
> > @@ -89,6 +89,10 @@ GetNextHidItem (
> >            return StartPos;
> > 
> >          }
> > 
> > 
> > 
> > +        //
> > 
> > +        // No break; here as this is an intentional fallthrough
> > 
> > +        //
> > 
> > +
> > 
> >        case 2:
> > 
> >          //
> > 
> >          // 2-byte data
> > 
> > @@ -99,6 +103,10 @@ GetNextHidItem (
> >            return StartPos;
> > 
> >          }
> > 
> > 
> > 
> > +        //
> > 
> > +        // No break; here as this is an intentional fallthrough
> > 
> > +        //
> > 
> > +
> > 
> >        case 3:
> > 
> >          //
> > 
> >          // 4-byte data, adjust size
> > 
> > --
> > 2.34.1
> > 
> > 
> > 
> > -=-=-=-=-=-=
> > Groups.io Links: You receive all messages sent to this group.
> > View/Reply Online (#109309):
> > https://edk2.groups.io/g/devel/message/109309
> > Mute This Topic: https://groups.io/mt/101750274/1643496
> > Group Owner: devel+owner@edk2.groups.io
> > Unsubscribe: https://edk2.groups.io/g/devel/unsub
> > [michael.d.kinney@intel.com]
> > -=-=-=-=-=-=
> > 
> 
> 
> 
> 
> 
> 


-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#109350): https://edk2.groups.io/g/devel/message/109350
Mute This Topic: https://groups.io/mt/101750274/7686176
Group Owner: devel+owner@edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/leave/12367111/7686176/1913456212/xyzzy [rebecca@openfw.io]
-=-=-=-=-=-=-=-=-=-=-=-