1 files changed, 50 insertions, 0 deletions
diff --git a/potrace/bitops.h b/potrace/bitops.h
new file mode 100644
index 0000000..89f4cb0
--- /dev/null
+++ b/potrace/bitops.h
@@ -0,0 +1,50 @@
+/* Copyright (C) 2001-2007 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+/* $Id: bitops.h 147 2007-04-09 00:44:09Z selinger $ */
+
+/* bits.h: this file defines some macros for bit manipulations. We
+   provide a generic implementation */
+
+/* lobit: return the position of the rightmost "1" bit of an int, or
+   32 if none. hibit: return 1 + the position of the leftmost "1" bit
+   of an int, or 0 if none. Note: these functions work on 32-bit
+   integers. */
+
+#ifndef BITOPS_H
+#define BITOPS_H
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+/* generic macros */
+
+static inline unsigned int lobit(unsigned int x) {
+  unsigned int res = 32;
+  while (x & 0xffffff) {
+    x <<= 8;
+    res -= 8;
+  }
+  while (x) {
+    x <<= 1;
+    res -= 1;
+  }
+  return res;
+}
+
+static inline unsigned int hibit(unsigned int x) {
+  unsigned int res = 0;
+  while (x > 0xff) {
+    x >>= 8;
+    res += 8;
+  }
+  while (x) {
+    x >>= 1;
+    res += 1;
+  }
+  return res;
+}
+
+#endif /* BITOPS_H */