Re: [libvirt] [PATCH v2 1/4] util: string: Introduce macro for automatic string lists

On Tue, Feb 26, 2019 at 04:48:23PM +0100, Peter Krempa wrote: > Similar to VIR_AUTOPTR, VIR_AUTOSTRINGLIST defines a list of strings > which will be freed if the pointer is leaving scope. > > Signed-off-by: Peter Krempa <pkrempa(a)redhat.com&gt; > --- > src/libvirt_private.syms | 1 + > src/util/virstring.c | 10 ++++++++++ > src/util/virstring.h | 10 ++++++++++ > 3 files changed, 21 insertions(+) > > diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms > index 038a744981..e68e3f3a3b 100644 > --- a/src/libvirt_private.syms > +++ b/src/libvirt_private.syms > @@ -2958,6 +2958,7 @@ virStringHasControlChars; > virStringIsEmpty; > virStringIsPrintable; > virStringListAdd; > +virStringListAutoFree; > virStringListFree; > virStringListFreeCount; > virStringListGetFirstWithPrefix; > diff --git a/src/util/virstring.c b/src/util/virstring.c > index e890dde546..8a791f96d4 100644 > --- a/src/util/virstring.c > +++ b/src/util/virstring.c > @@ -318,6 +318,16 @@ void virStringListFree(char **strings) > } > > > +void virStringListAutoFree(char ***strings) > +{ > + if (!*strings) > + return; > + > + virStringListFree(*strings); > + *strings = NULL; > +} > + > + > /** > * virStringListFreeCount: > * @strings: array of strings to free > diff --git a/src/util/virstring.h b/src/util/virstring.h > index aef82471c2..d14b7f4f49 100644 > --- a/src/util/virstring.h > +++ b/src/util/virstring.h > @@ -53,6 +53,7 @@ int virStringListCopy(char ***dst, > const char **src); > > void virStringListFree(char **strings); > +void virStringListAutoFree(char ***strings); > void virStringListFreeCount(char **strings, > size_t count); > > @@ -307,6 +308,15 @@ int virStringParsePort(const char *str, > unsigned int *port) > ATTRIBUTE_NONNULL(2) ATTRIBUTE_RETURN_CHECK; > > +/** > + * VIR_AUTOSTRINGLIST: > + * > + * Declares a NULL-terminated list of strings which will be automatically freed > + * when the pointer goes out of scope. > + */ > +# define VIR_AUTOSTRINGLIST \ > + __attribute__((cleanup(virStringListAutoFree))) char ** > + IIRC at the beginning we said that all the VIR_AUTO macros should be consistent in terms of how we use the macro, IOW: VIR_AUTOFREE(type) VIR_AUTOPTR(type) VIR_AUTOCLEAN(type) although I can't say I personally don't like your version, nevertheless, as I said we should remain consistent and use 'char **' explicitly when using the macro.