From: Lennart Poettering <lennart@poettering.net>
Date: Thu, 30 Jan 2014 15:46:48 +0000 (+0100)
Subject: util: add u32ctz() call for determining ctz of uint32_t
X-Git-Tag: v209~280
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=commitdiff_plain;h=ec417ccc276f245382e1dc3c7b0599a878160193

util: add u32ctz() call for determining ctz of uint32_t
---

diff --git a/src/shared/util.h b/src/shared/util.h
index 117855de8..e4de4728b 100644
--- a/src/shared/util.h
+++ b/src/shared/util.h
@@ -743,7 +743,19 @@ static inline void _reset_umask_(struct _umask_struct_ *s) {
              _saved_umask_.quit = true)
 
 static inline unsigned u64log2(uint64_t n) {
+#if __SIZEOF_LONG_LONG__ == 8
         return (n > 1) ? (unsigned) __builtin_clzll(n) ^ 63U : 0;
+#else
+#error "Wut?"
+#endif
+}
+
+static inline unsigned u32ctz(uint32_t n) {
+#if __SIZEOF_INT__ == 4
+        return __builtin_ctz(n);
+#else
+#error "Wut?"
+#endif
 }
 
 static inline bool logind_running(void) {