From: Rich Felker <dalias@aerifal.cx>
Date: Sat, 24 Feb 2018 17:33:06 +0000 (-0500)
Subject: use idiomatic safe form for FUNLOCK macro
X-Git-Tag: v1.1.20~145
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=455bd824457b3e6cc3998817aac4e500b027cc50;p=oweals%2Fmusl.git

use idiomatic safe form for FUNLOCK macro

previously this macro used an odd if/else form instead of the more
idiomatic do/while(0), making it unsafe against omission of trailing
semicolon. the omission would make the following statement conditional
instead of producing an error.
---

diff --git a/src/internal/stdio_impl.h b/src/internal/stdio_impl.h
index 7cdf729d..1127a492 100644
--- a/src/internal/stdio_impl.h
+++ b/src/internal/stdio_impl.h
@@ -9,7 +9,7 @@
 
 #define FFINALLOCK(f) ((f)->lock>=0 ? __lockfile((f)) : 0)
 #define FLOCK(f) int __need_unlock = ((f)->lock>=0 ? __lockfile((f)) : 0)
-#define FUNLOCK(f) if (__need_unlock) __unlockfile((f)); else
+#define FUNLOCK(f) do { if (__need_unlock) __unlockfile((f)); } while (0)
 
 #define F_PERM 1
 #define F_NORD 4