Re: v5 [PATCH 6/6] nsswitch: use new internal API (callers)

[DJ Delorie <dj@redhat.com>]

Andreas Schwab <schwab@linux-m68k.org> writes:
> On Feb 17 2021, DJ Delorie wrote:
>
>> Andreas Schwab <schwab@linux-m68k.org> writes:
>>
>>> On Feb 17 2021, DJ Delorie wrote:
>>>
>>>> +  /* Neither found, use default config.  */
>>>> +  *ni = __nss_action_parse (defconfig);
>>>> +  if (*ni != NULL)
>>>> +    return 0;
>>>> +
>>>> +  /* Failure.  */
>>>> +  return -1;
>>>
>>> How can that ever be reached?
>>
>> Passing a syntactically incorrect string as defconfig, or memory
>> allocation failure.
>
> defconfig isn't used before that point.

*ni = __nss_action_parse (defconfig);

If defconfig is syntactically invalid, __nss_action_parse can't parse
it, and returns NULL.

If parsing defconfig requires allocating memory, and the allocation
fails, __nss_action_parse returns NULL.

If either of these cases happens, we report failure by returning -1.

Either that or I'm totally misunderstanding what you're asking.  Which
"that" are you asking how it can be reached?

If you're refering to the "Neither found" comment, it reaches that if
nsswitch.conf mentions neither the primary nor alternate service name.