Re: [PATCH 0/6] Add support for interface binding

On 1/22/19 12:40 PM, Bill Fenner wrote:
> On Wed, Nov 7, 2018 at 1:26 AM Bart Van Assche <[email protected] 
> <mailto:[email protected]>> wrote:
> 
>     On 11/6/18 8:03 AM, Bill Fenner wrote:
>      > Given your proposed code structure, I imagine that we could add
>     network
>      > namespaces to netsnmp_ep too - this basically ends up using
>     "socketat(
>      > /* magic */, family, type, protocol )" instead of socket() to
>     create the
>      > socket, and the magic can be derived from what we store in ep.
> 
>     That sounds like a good idea to me.
> 
> 
> I've finally done this, and would like to request some eyes on it before 
> I push it to 5-8-patches.
> 
> https://github.com/fenner/net-snmp/compare/V5-8-patches...fenner:linux-namespace

Hi Bill,

The following new code in netsnmp_parse_ep_str() looks a bit fragile to me:

             cp = strchr(iface, '@');
             if (!cp)
                 cp = strchr(iface, ':');

Wouldn't it be better to backtrack to the previous value of 'cp' if no 
second '@' sign is found? That will avoid that this code fails if 
support for a new delimiter between '@' and ':' would be added.

The following code looks unusual to me:

#ifdef HAVE_SETNS
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <unistd.h>
#include <signal.h>
#include <sched.h>
#include <net-snmp/library/snmp_assert.h>
#endif

I'm not aware of any other Net-SNMP code that guards include directives 
with the result of a test for a system call.

Otherwise the code looks fine to me. But please keep in mind that I only 
had a quick look at it.

Bart.