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Diffstat (limited to 'lib/libc/strings/ffs.c')
-rw-r--r--lib/libc/strings/ffs.c14
1 files changed, 14 insertions, 0 deletions
diff --git a/lib/libc/strings/ffs.c b/lib/libc/strings/ffs.c
new file mode 100644
index 00000000..3b836021
--- /dev/null
+++ b/lib/libc/strings/ffs.c
@@ -0,0 +1,14 @@
+int ffs(int i)
+{
+ if (i == 0)
+ return 0;
+
+ int pos = 1;
+ unsigned int u = (unsigned int)i;
+
+ while ((u & 1U) == 0U) {
+ u >>= 1;
+ pos++;
+ }
+ return pos;
+}