7.0 - ifconfig create is not working as expected?

[Sam Leffler]

Sam Leffler wrote:
> Eugene Grosbein wrote:
>> On Sun, Mar 30, 2008 at 01:14:36PM +0200, Remko Lodder wrote:
>>
>>  
>>> Given that the idea is that we dont expect to get to this anytime  
>>> soon, we welcome the person who does the analysis for us so that we  
>>> might be able to fix this quicker (if possible with all the changes  
>>> involved).
>>>     
>>
>> Here is a patch for RELENG_7. I ask Miroslav Lachman to test it.
>> Apply:
>>
>> cd /usr/src/sbin/ifconfig
>> patch < /path/to/patchfile
>> make
>>
>> Test:
>>
>> ./ifconfig lo1 create inet 5.5.5.5 netmask 255.255.255.0
>>
>> Or full-blown syntax:
>>
>> ./ifconfig gif0 create inet 6.6.6.6 7.7.7.7 tunnel 1.1.1.1 2.2.2.2 \
>> netmask 255.255.255.255 mtu 1500 link2
>>
>> Index: ifclone.c
>> ===================================================================
>> RCS file: /home/ncvs/src/sbin/ifconfig/ifclone.c,v
>> retrieving revision 1.3
>> diff -u -r1.3 ifclone.c
>> --- ifclone.c    12 Aug 2006 18:07:17 -0000    1.3
>> +++ ifclone.c    30 Mar 2008 14:19:08 -0000
>> @@ -131,7 +131,9 @@
>>  static
>>  DECL_CMD_FUNC(clone_create, arg, d)
>>  {
>> -    callback_register(ifclonecreate, NULL);
>> +    if (strstr(name, "vlan") == name)
>> +        callback_register(ifclonecreate, NULL);
>> +    else ifclonecreate(s, NULL);
>>   
>
> This breaks other cloning operations (e.g. wlan vaps that are about to 
> show up in HEAD).  In general it is wrong to embed knowledge about one 
> type of cloning op in the common clone code.  If you want to add the 
> notion of cloning operations that should be done immediately vs. ones 
> that should be deferred then do it generically; not by hacks like 
> this.  Understand however that now !vlan clone operations behave 
> differently than vlans and many people will be utterly confused by the 
> inconsistency.
>
>>  }
>>  
>>  static
>> Index: ifconfig.c
>> ===================================================================
>> RCS file: /home/ncvs/src/sbin/ifconfig/ifconfig.c,v
>> retrieving revision 1.134
>> diff -u -r1.134 ifconfig.c
>> --- ifconfig.c    4 Oct 2007 09:45:41 -0000    1.134
>> +++ ifconfig.c    30 Mar 2008 14:22:00 -0000
>> @@ -247,7 +247,12 @@
>>                  if (iflen >= sizeof(name))
>>                      errx(1, "%s: cloning name too long",
>>                          ifname);
>> -                ifconfig(argc, argv, NULL);
>> +                if (argc > 1) {
>> +                    afp = af_getbyname(argv[1]);
>> +                    if (afp != NULL)
>> +                        argv[1] = NULL;
>> +                }
>> +                ifconfig(argc, argv, afp);
>>                  exit(0);
>>              }
>>              errx(1, "interface %s does not exist", ifname);
>> @@ -451,6 +456,9 @@
>>      while (argc > 0) {
>>          const struct cmd *p;
>>  
>> +        if(*argv == NULL)
>> +            goto next;
>> +                     p = cmd_lookup(*argv);
>>          if (p == NULL) {
>>              /*
>> @@ -479,6 +487,7 @@
>>              } else
>>                  p->c_u.c_func(*argv, p->c_parameter, s, afp);
>>          }
>> +    next:
>>          argc--, argv++;
>>      }
>>   
>
> Aside from not maintaining prevailing style and breaking cloning of 
> other devices you seem to understand the issue.  How to handle it is 
> however unclear.  I considered making 2 passes over the arguments to 
> collect those required for a clone operation but never got to it.  
> That still seems like the correct approach.

It might be simpler to just do 1 pass over the args and push the clone 
callback on the first non-clone parameter.  Right now however there's no 
way to tell what is clone-related and what is not.

    Sam