On 2/1/21 4:51 AM, Peter Krempa wrote:
On Mon, Feb 01, 2021 at 10:47:47 +0100, Peter Krempa wrote:
> On Mon, Feb 01, 2021 at 10:18:52 +0100, Michal Privoznik wrote:
>> On 2/1/21 7:27 AM, Laine Stump wrote:
>>> virHashFree() just calls g_hash_table_unref(), and it's more common
>>> for libvirt code to call virHashFree() rather than the convoluted
>>> calling of g_hash_table_unref() via g_clear_pointer().
>>>
>>> Since the object containing the hashes is g_freed immediately after
>>> the hashes are freed, there is no functional difference.
>>>
>>> Signed-off-by: Laine Stump <laine(a)redhat.com>
>>> ---
>>> src/conf/domain_addr.c | 4 ++--
>>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/src/conf/domain_addr.c b/src/conf/domain_addr.c
>>> index 37dad20ade..a8648d5858 100644
>>> --- a/src/conf/domain_addr.c
>>> +++ b/src/conf/domain_addr.c
>>> @@ -949,8 +949,8 @@
virDomainPCIAddressSetExtensionFree(virDomainPCIAddressSetPtr addrs)
>>> if (!addrs || !addrs->zpciIds)
>>> return;
>>> - g_clear_pointer(&addrs->zpciIds->uids, g_hash_table_unref);
>>> - g_clear_pointer(&addrs->zpciIds->fids, g_hash_table_unref);
>>> + virHashFree(addrs->zpciIds->uids);
>>> + virHashFree(addrs->zpciIds->fids);
>>> VIR_FREE(addrs->zpciIds);
>>> }
>>>
>> virHashFree documents itself as being deprecated in favor of
>> g_hash_table_unref().
>>
>> While I like our virSomething wrappers (mostly because I'm used to them more
>> than to their glib counterparts; but then you also have glib functions when
>> one thinks that glib implementation is interchangeable with ours but it
>> isn't - devil's in the details), I think our intent is to drop
>> virHashFree().
>>
>> But then again - we didn't, instead we replaced virHash* internals with
>> glib, so I can argue that being consistent is more important than being
>> progressive.
>>
>> Your call, but since you build next patch on this one, I'm inclined to say
>> it's okay to merge it.
> It's a NACK from me. That was deliberate. Especially virHashFree doesn't
> clear the pointer, the code which we have does.
Oh, and one more reason. Those hash tables are allocated directly by the
glib function since they don't use strings as keys which is the only
wrapper that virHash provides, thus they should not be freed by the
wrappers.
Yeah, I was looking too narrow and didn't notice that. (once again
proving the utility of peer reviews!)
I do still think that we shouldn't be unnecessarily using
g_clear_pointer(), but I'll just drop the patch for now, and maybe
revisit the next time I pass this way.
(NB: If we really think that virHash should be deprecated, then we
should start converting. And if we instead think that its new
g_hash_table-based implementation is a useful value-add on top of the
straight glib API, then we should remove the "deprecated" notes from
virhash.c, and change this usage to (fully, not half-assed like I did)
use virHash like everyone else. No, I'm not volunteering!)