On Jun 15, 2007, at 1:45 PM, Ralf S. Engelschall wrote:
On Fri, Jun 15, 2007, Jeff Johnson wrote:Yes, I've seen that _free is spreaded in the sources in a ratherredundant way. What about the following in system.h and then replace all"foo = _free(foo);" with just "xfree(foo)"? #define xfree(p) \ do { \ if ((p) != NULL) { \ free((void *)(p)); \ (p) = NULL; \ } \ } while (0)This way the free is not even inside a sub-function (helps in debugging)and you don't have to add a _free function to such a lot of source files. But perhaps I'm just overlooking something here...The reason I did not do that is because of the (p) = NULL; side effect.[...]Can you be more specific, Jeff? What side-effect are you talking about?Are you talking about the fact that the macro argument is evaluated multiple times? That's right, but I hope you just plan to do plain xfree(foo) calls where "foo" is a simple variable name and not things like xfree(array[counter++]) or such obvious side-effect troubling things. IMHO this drawback of potential side-effects is less horrible than having dozend of _free definitions floating around, isn't it?
Sorry for imprecise use of "side-effect". I did not mean the
classic "side effect" usage of macro defines such as
xfree(p++)
which, duh, breaks your xfree define. I'm perfectly willing to be
punished
if I choose to code "xfree(p++)" or equivalent.Perhaps "hidden" is the more accurate term to express why I did not choose
an xfree() #define. I could have designed around void destructor() of which xfree() is an example. Instead for idiosyncratic reasons I chose foo = destructor(foo); and tried to follow that paradigm. Meanwhile, most, at least the important, objects in rpm are refcounted which is an entirely different usage case than malloc/free anyways.No matter what, I'd love to stamp out the multiple static inline _free () crapola.
system.h is per-rpm-build only, not installed or distributed. rpmlib.h has a _free() definition, but as code spread to rpmdb -> rpmio, I had to invent new locations for _free() One of the rpmio/*.h files is likely best place to instantiate _free._free is just another fetish, likely fear of public embarassment is what stopped me from doing years ago. I'll figger a place and get rid of the multiple copies
of _free() this weekend. 73 de Jeff ______________________________________________________________________ RPM Package Manager http://rpm5.org Developer Communication List rpm-devel@rpm5.org
