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authorPeter S. Mazinger <ps.m@gmx.net>2006-01-03 14:50:18 +0000
committerPeter S. Mazinger <ps.m@gmx.net>2006-01-03 14:50:18 +0000
commit167d5e33fcb821e51e2f9dcf460591737c3c7972 (patch)
tree79acefdd8c9781098adbf77278415eda6365fd3d /libc/string/ffs.c
parentfe68563b9a070fedf117c8738652587945427bb3 (diff)
Complete split of all the string functions. Hope haven't broken too much. wcscoll/strcoll needs some love ...
Diffstat (limited to 'libc/string/ffs.c')
-rw-r--r--libc/string/ffs.c54
1 files changed, 54 insertions, 0 deletions
diff --git a/libc/string/ffs.c b/libc/string/ffs.c
new file mode 100644
index 000000000..fc76e6c70
--- /dev/null
+++ b/libc/string/ffs.c
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2002 Manuel Novoa III
+ * Copyright (C) 2000-2005 Erik Andersen <andersen@uclibc.org>
+ *
+ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+ */
+
+/* ffsl,ffsll */
+
+#include "_string.h"
+
+int attribute_hidden __ffs(int i)
+{
+#if 1
+ /* inlined binary search method */
+ char n = 1;
+#if UINT_MAX == 0xffffU
+ /* nothing to do here -- just trying to avoiding possible problems */
+#elif UINT_MAX == 0xffffffffU
+ if (!(i & 0xffff)) {
+ n += 16;
+ i >>= 16;
+ }
+#else
+#error ffs needs rewriting!
+#endif
+
+ if (!(i & 0xff)) {
+ n += 8;
+ i >>= 8;
+ }
+ if (!(i & 0x0f)) {
+ n += 4;
+ i >>= 4;
+ }
+ if (!(i & 0x03)) {
+ n += 2;
+ i >>= 2;
+ }
+ return (i) ? (n + ((i+1) & 0x01)) : 0;
+
+#else
+ /* linear search -- slow, but small */
+ int n;
+
+ for (n = 0 ; i ; ++n) {
+ i >>= 1;
+ }
+
+ return n;
+#endif
+}
+
+strong_alias(__ffs,ffs)