Import regex from OpenBSD
Change-Id: I7ad7d907ef65e4e345f94777d730813b1270a612
diff --git a/libc/regex/utils.h b/libc/regex/utils.h
new file mode 100644
index 0000000..3e184fc
--- /dev/null
+++ b/libc/regex/utils.h
@@ -0,0 +1,55 @@
+/* $OpenBSD: utils.h,v 1.4 2003/06/02 20:18:36 millert Exp $ */
+
+/*-
+ * Copyright (c) 1992, 1993, 1994 Henry Spencer.
+ * Copyright (c) 1992, 1993, 1994
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Henry Spencer.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * @(#)utils.h 8.3 (Berkeley) 3/20/94
+ */
+
+/* utility definitions */
+#define DUPMAX 255
+#define INFINITY (DUPMAX + 1)
+#define NC (CHAR_MAX - CHAR_MIN + 1)
+typedef unsigned char uch;
+
+/* switch off assertions (if not already off) if no REDEBUG */
+#ifndef REDEBUG
+#ifndef NDEBUG
+#define NDEBUG /* no assertions please */
+#endif
+#endif
+#include <assert.h>
+
+/* for old systems with bcopy() but no memmove() */
+#ifdef USEBCOPY
+#define memmove(d, s, c) bcopy(s, d, c)
+#endif