Add regular expression matching support, based on OpenBSD regexec()/regcomp()
implementation.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80493 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/regutils.h b/lib/Support/regutils.h
new file mode 100644
index 0000000..7150a3f
--- /dev/null
+++ b/lib/Support/regutils.h
@@ -0,0 +1,55 @@
+/*-
+ * This code is derived from OpenBSD's libc/regex, original license follows:
+ *
+ * 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		_POSIX2_RE_DUP_MAX	/* xxx is this right? */
+#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