Re: [RFC]__sock_create() change

Razvan Deaconescu <razvan@xxxxxxxxxxxxxxxxxx> · Mon, 14 May 2007 10:59:53 +0300

pradeep singh wrote:
Hi All,

the __sock_create in net/socket.c has the following code snippet.

if (family == PF_INET && type == SOCK_PACKET) {
     static int warned;
     if (!warned) {
          warned = 1;
          printk(KERN_INFO "%s uses obsolete (PF_INET,SOCK_PACKET)\n", 
current->comm);
     }
     family = PF_PACKET;
}

this may be in place to emit a harmless warning , but why not change it 
to -
if (family == PF_INET && type == SOCK_PACKET) {

     printk(KERN_INFO "%s uses obsolete (PF_INET,SOCK_PACKET)\n", 
current->comm);

     family = PF_PACKET;
}

Because anyway if(!warning) is going to result in true everytime we 
enter the function, as static int warning has scope limited to the outer 
if block.

Not quite so. The warning variable may only have scope within its block 
,but (being static) is stored in a reserved memory area (I think this is 
called linkage ... not sure though). The second time someone would try 
creating a socket using PF_INET and SOCK_PACKET, he/she would not get 
that warning as 'warning' is already set (warning = 1, that is).

Razvan

--
To unsubscribe from this list: send an email with
"unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx
Please read the FAQ at http://kernelnewbies.org/FAQ