[PATCH 21/23] Switch away from virHashFree

[Peter Krempa]

On Tue, Nov 30, 2021 at 15:14:14 +0000, Daniel P. Berrangé wrote:
> On Tue, Nov 30, 2021 at 03:32:05PM +0100, Peter Krempa wrote:
> > Use 'g_clear_pointer(&ptr, g_hash_table_unref)' instead.
> > 
> > In few instances it allows us to also remove explicit clearing of
> > pointers.
> > 
> > Signed-off-by: Peter Krempa <pkrempa at redhat.com>
> > ---
> >  src/conf/domain_addr.c                 |  2 +-
> >  src/conf/domain_conf.c                 |  2 +-
> >  src/conf/nwfilter_conf.c               |  2 +-
> >  src/conf/nwfilter_ipaddrmap.c          |  3 +--
> >  src/conf/virchrdev.c                   |  2 +-
> >  src/conf/virdomainmomentobjlist.c      |  2 +-
> >  src/conf/virdomainobjlist.c            |  4 ++--
> >  src/conf/virinterfaceobj.c             |  2 +-
> >  src/conf/virnetworkobj.c               |  4 ++--
> >  src/conf/virnodedeviceobj.c            |  2 +-
> >  src/conf/virnwfilterbindingdef.c       |  2 +-
> >  src/conf/virnwfilterbindingobjlist.c   |  2 +-
> >  src/conf/virsecretobj.c                |  2 +-
> >  src/conf/virstorageobj.c               | 10 +++++-----
> >  src/hyperv/hyperv_wmi.c                |  2 +-
> >  src/hypervisor/virclosecallbacks.c     |  2 +-
> >  src/libxl/libxl_logger.c               |  2 +-
> >  src/locking/lock_daemon.c              |  2 +-
> >  src/nwfilter/nwfilter_dhcpsnoop.c      |  6 +++---
> >  src/nwfilter/nwfilter_gentech_driver.c |  2 +-
> >  src/nwfilter/nwfilter_learnipaddr.c    |  7 ++-----
> >  src/qemu/qemu_domain.c                 |  2 +-
> >  src/qemu/qemu_driver.c                 |  2 +-
> >  src/rpc/virnetdaemon.c                 |  2 +-
> >  src/security/security_selinux.c        |  6 +++---
> >  src/util/virfilecache.c                |  2 +-
> >  src/util/virhash.c                     |  2 +-
> >  src/util/virlockspace.c                |  2 +-
> >  src/util/virmacmap.c                   |  2 +-
> >  src/util/virsystemd.c                  |  2 +-
> >  tests/nwfilterxml2firewalltest.c       |  2 +-
> >  tests/qemusecuritymock.c               |  7 +++----
> >  32 files changed, 45 insertions(+), 50 deletions(-)
> > 
> > diff --git a/src/conf/domain_addr.c b/src/conf/domain_addr.c
> > index a06721c35d..49745ba881 100644
> > --- a/src/conf/domain_addr.c
> > +++ b/src/conf/domain_addr.c
> > @@ -1377,7 +1377,7 @@ void virDomainCCWAddressSetFree(virDomainCCWAddressSet *addrs)
> >      if (!addrs)
> >          return;
> > 
> > -    virHashFree(addrs->defined);
> > +    g_clear_pointer(&addrs->defined, g_hash_table_unref);
> 
> This is in a Free() method, so we should just be calling
> g_hash_table_unref directly.  Likewise for all the other

g_hash_table_unref requires a valid GHashTable pointer to be passed.

g_clear_pointer ensures that we don't call it while the freed table
would be NULL.

Most Free* methods are also used on cleanup paths when the insides of
the struct may still be NULL and IMO it's not worth analyzing the code
and neither converting to:

 if (htptr)
    g_hash_table_unref(htptr);

for the instances where setting the variable to NULL is pointless.