[libvirt] [PATCH 15/15] util: Introduce VIR_DEFINE_AUTOPTR_FUNC for virStorageSource

[John Ferlan]

On 2/8/19 3:07 AM, Erik Skultety wrote:
> On Wed, Feb 06, 2019 at 08:41:47AM -0500, John Ferlan wrote:
>> Let's make use of the auto __cleanup capabilities cleaning up any
>> now unnecessary goto paths. A few methods were modified to use a
>> more common methodology of defining/using @def and then stealing
>> the pointer to @ret to return allowing @def to be autofree'd if
>> the swap didn't occur on various return NULL; error paths.
>>
>> Signed-off-by: John Ferlan <jferlan at redhat.com>
> 
> This patch fails to compile with MinGW:
> https://travis-ci.org/eskultety/libvirt/jobs/490018031
> ...although I don't understand why
> 

Strange... Although I do have a recollection of seeing that inline error
message though.  Still I'll rework this one to extract out some stuff
and repost as a v2 once I walk through all the changes I have made to
date from code review to ensure I've covered all the comments raised.

Thanks -

John

>>
>> @@ -4977,10 +4955,9 @@ int
>>  virStorageFileGetBackingStoreStr(virStorageSourcePtr src,
>>                                   char **backing)
>>  {
>> -    virStorageSourcePtr tmp = NULL;
>> +    VIR_AUTOPTR(virStorageSource) tmp = NULL;
>>      VIR_AUTOFREE(char *) buf = NULL;
>>      ssize_t headerLen;
>> -    int ret = -1;
>>      int rv;
>>
>>      *backing = NULL;
>> @@ -5005,17 +4982,12 @@ virStorageFileGetBackingStoreStr(virStorageSourcePtr src,
>>      }
>>
>>      if (!(tmp = virStorageSourceCopy(src, false)))
>> -        goto cleanup;
>> +        return -1;
>>
>>      if (virStorageFileGetMetadataInternal(tmp, buf, headerLen, NULL) < 0)
>> -        goto cleanup;
>> +        return -1;
>>
>>      VIR_STEAL_PTR(*backing, tmp->backingStoreRaw);
>>
>> -    ret = 0;
>> -
>> - cleanup:
>> -    virStorageSourceFree(tmp);
>> -
>> -    return ret;
>> +    return 0;
>>  }
> 
> ... for example in ^this function, I don't quite understand why it thinks that
> the call is unlikely, is it because virStorageFileGetBackingStoreStr is only
> being called from qemuDomainSnapshotDiskDataCollect?
> 
> Erik
>