On Sun, Mar 24, 2024 at 12:37:53AM +0300, Vitaly Chikunov wrote: > On Sat, Mar 23, 2024 at 02:56:43PM +0100, Phil Sutter wrote: > > On Sat, Mar 23, 2024 at 06:06:41AM +0300, Vitaly Chikunov wrote: > > > Frequently when addr/mask is printed xtables_ipaddr_to_numeric and > > > xtables_ipmask_to_numeric are called together in one printf call but > > > xtables_ipmask_to_numeric internally calls xtables_ipaddr_to_numeric > > > which prints into the same static buffer causing buffer to be > > > overwritten and addr/mask incorrectly printed in such call scenarios. > > > > > > Make xtables_ipaddr_to_numeric to use two static buffers rotating their > > > use. This simplistic approach will leave ABI not changed and cover all > > > such use cases. > > > > I don't quite like the cat'n'mouse game this opens, although it's > > unlikely someone calls it a third time before copying the buffer. > > > > What do you think about the attached solution? > > Your approach is indeed much better. But why double underscore prefix > to a function name, this sounds like reserved identifiers. Well, for once it was just a quick sketch. Also, when refactoring into an inner function it is not uncommon to prefix it this way, at least if it's an internal-only function. Another option I could think of is _r suffix, typically used for reentrant variants. Cheers, Phil
