[libvirt] [PATCHv2] build: use gnulib passfd for simpler SCM_RIGHTS code

[Laine Stump]

On 04/25/2011 10:21 AM, Eric Blake wrote:
> On 04/25/2011 01:17 AM, Laine Stump wrote:
>>> @@ -1529,26 +1513,20 @@ virFileOpenAs(const char *path, int openflags,
>>> mode_t mode,
>>>            VIR_FORCE_CLOSE(pair[1]);
>>>
>>>            do {
>>> -            ret = recvmsg(pair[0],&msg, 0);
>>> +            ret = recvfd(pair[0], 0);
>>>            } while (ret<   0&&   errno == EINTR);
> ret == -1 and errno == EACCES on failure to transfer fd...
>
>>> -        if (ret<   0) {
>>> +        if (ret<   0&&   errno != EACCES) {
>>>                ret = -errno;
>>>                VIR_FORCE_CLOSE(pair[0]);
>>>                while ((waitret = waitpid(pid, NULL, 0) == -1)
>>>                       &&   (errno == EINTR));
>>>                goto parenterror;
>>> +        } else {
>>> +            fd = ret;
>>>            }
> so now fd == -1...
>
>
>>          if (!WIFEXITED(status) || (ret = -WEXITSTATUS(status)) == -EACCES ||
>>              fd == -1) {
>>              /* fall back to the simpler method, which works better in
>>               * some cases */
>>              return virFileOpenAsNoFork(path, openflags, mode, uid, gid, flags);
>>          }
> so this uses the fallback code, regardless of child exit status, and we
> also ensured that the child got reaped.
>
>> What if errno == EACCES? Will we be getting all the error recovery we
>> need in the caller?
> Yes.

Okay. In that case, ACK.