On Mon, Mar 07, 2022 at 11:43:05AM +0100, Martin Kletzander wrote: > On Mon, Mar 07, 2022 at 10:01:40AM +0000, Daniel P. Berrangé wrote: > > On Mon, Mar 07, 2022 at 10:04:06AM +0100, Martin Kletzander wrote: > > > When libc uses a define to rewrite stat64 to stat our mocks do not work if they > > > are chained because the symbol that we are looking up is being stringified and > > > therefore preventing the stat64->stat expansion per C-preprocessor rules. One > > > stringification macro is just enough to make it work. > > > > This doesn't sound right to me. > > > > If we're implementing a mock for 'stat64', we should not be looking > > up 'stat'. We should be implmenting a mock for 'stat' instead. > > > > It sounds more like we got MOCK_STAT and MOCK_STAT64 incorrectly > > defined surely. > > > > I spent three days trying to figure this out. But with this fix we are > actually doing what you are suggesting. All the (l)stat64 are being > replaced by (l)stat, so even: > > int lstat64(const char *path, struct stat64 *statbuf) > > is actually rewritten to > > int lstat(const char *path, struct stat *statbuf) > > because the define applies to the struct name as well. The only > difference is that internally it will use the real_lstat64 function > pointer, but the function declaration is correct. And if you enable > debugging it will say that lstat64 is being redirected, but that's a > pretty minor issue, if it is one at all. > > What we could do is rewrite the macros so that all of the above is > properly expanded/substituted, but I do not think that is the way we > want to do things as it looked a bit messy (I probably still have that > commit somewhere. Ok, thanks for the explanation. Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
