From ae2a15bc14bc448e625ad93fd044bc077ede4b3f Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Thu, 22 Mar 2018 16:53:26 +0100 Subject: macro: introduce TAKE_PTR() macro This macro will read a pointer of any type, return it, and set the pointer to NULL. This is useful as an explicit concept of passing ownership of a memory area between pointers. This takes inspiration from Rust: https://doc.rust-lang.org/std/option/enum.Option.html#method.take and was suggested by Alan Jenkins (@sourcejedi). It drops ~160 lines of code from our codebase, which makes me like it. Also, I think it clarifies passing of ownership, and thus helps readability a bit (at least for the initiated who know the new macro) --- src/shared/fdset.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'src/shared/fdset.c') diff --git a/src/shared/fdset.c b/src/shared/fdset.c index 9ce1295223..845c19b1cf 100644 --- a/src/shared/fdset.c +++ b/src/shared/fdset.c @@ -25,6 +25,7 @@ #include "sd-daemon.h" +#include "alloc-util.h" #include "dirent-util.h" #include "fd-util.h" #include "fdset.h" @@ -168,8 +169,7 @@ int fdset_new_fill(FDSet **_s) { } r = 0; - *_s = s; - s = NULL; + *_s = TAKE_PTR(s); finish: /* We won't close the fds here! */ -- cgit v1.2.1