Re: Goto statements in the Kernel

[Thomas Petazzoni <thomas.petazzoni@xxxxxxxx>]

Hi,

Bob Smith a écrit :

> Why is that ? I googled up reasons like minimizing return points,
> but is that it ?

Most of the time, 'goto' is used to minimize code duplication in error
handling.

Without 'goto':

int myfunc (void)
{
   ret = dosomething1();
   if (ret < 0)
     return ret;

   ret = dosomething2();
   if (ret < 0)
   {
     undosomething1();
     return ret;
   }

   ret = dosomething3();
   if (ret < 0)
   {
     undosomething2();
     undosomething1();
     return ret;
   }

   ret = dosomething4();
   if (ret < 0)
   {
     undosomething3();
     undosomething2();
     undosomething1();
     return ret;
   }
  return 0;
}

With 'goto':

int myfunc(void)
{
   ret = dosomething1()
   if (ret < 0)
     goto ret_dosomething1;

   ret = dosomething2()
   if (ret < 0)
     goto ret_dosomething2;

   ret = dosomething3()
   if (ret < 0)
     goto ret_dosomething3;

   ret = dosomething4()
   if (ret < 0)
     goto ret_dosomething4;

ret_dosomething4:
  undosomething3();
ret_dosomething3:
  undosomething2();
ret_dosomething2:
  undosomething1();
ret_dosomething1:
  return ret;
}

Sincerly,

Thomas
-- 
PETAZZONI Thomas - thomas.petazzoni@xxxxxxxx
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