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

1 files changed, 131 insertions, 0 deletions

diff --git a/lib/Support/regerror.c b/lib/Support/regerror.c
new file mode 100644
index 0000000000..88d33b8862
--- /dev/null
+++ b/lib/Support/regerror.c
@@ -0,0 +1,131 @@
+/*-
+ * 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.
+ *
+ *	@(#)regerror.c	8.4 (Berkeley) 3/20/94
+ */
+
+#include <sys/types.h>
+#include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+#include <limits.h>
+#include <stdlib.h>
+#include "regex_impl.h"
+
+#include "regutils.h"
+
+static const char *regatoi(const llvm_regex_t *, char *, int);
+
+static struct rerr {
+	int code;
+	const char *name;
+	const char *explain;
+} rerrs[] = {
+	{ REG_NOMATCH,	"REG_NOMATCH",	"llvm_regexec() failed to match" },
+	{ REG_BADPAT,	"REG_BADPAT",	"invalid regular expression" },
+	{ REG_ECOLLATE,	"REG_ECOLLATE",	"invalid collating element" },
+	{ REG_ECTYPE,	"REG_ECTYPE",	"invalid character class" },
+	{ REG_EESCAPE,	"REG_EESCAPE",	"trailing backslash (\\)" },
+	{ REG_ESUBREG,	"REG_ESUBREG",	"invalid backreference number" },
+	{ REG_EBRACK,	"REG_EBRACK",	"brackets ([ ]) not balanced" },
+	{ REG_EPAREN,	"REG_EPAREN",	"parentheses not balanced" },
+	{ REG_EBRACE,	"REG_EBRACE",	"braces not balanced" },
+	{ REG_BADBR,	"REG_BADBR",	"invalid repetition count(s)" },
+	{ REG_ERANGE,	"REG_ERANGE",	"invalid character range" },
+	{ REG_ESPACE,	"REG_ESPACE",	"out of memory" },
+	{ REG_BADRPT,	"REG_BADRPT",	"repetition-operator operand invalid" },
+	{ REG_EMPTY,	"REG_EMPTY",	"empty (sub)expression" },
+	{ REG_ASSERT,	"REG_ASSERT",	"\"can't happen\" -- you found a bug" },
+	{ REG_INVARG,	"REG_INVARG",	"invalid argument to regex routine" },
+	{ 0,		"",		"*** unknown regexp error code ***" }
+};
+
+/*
+ - llvm_regerror - the interface to error numbers
+ = extern size_t llvm_regerror(int, const llvm_regex_t *, char *, size_t);
+ */
+/* ARGSUSED */
+size_t
+llvm_regerror(int errcode, const llvm_regex_t *preg, char *errbuf, size_t errbuf_size)
+{
+	struct rerr *r;
+	size_t len;
+	int target = errcode &~ REG_ITOA;
+	const char *s;
+	char convbuf[50];
+
+	if (errcode == REG_ATOI)
+		s = regatoi(preg, convbuf, sizeof convbuf);
+	else {
+		for (r = rerrs; r->code != 0; r++)
+			if (r->code == target)
+				break;
+	
+		if (errcode&REG_ITOA) {
+			if (r->code != 0) {
+				assert(strlen(r->name) < sizeof(convbuf));
+				(void) llvm_strlcpy(convbuf, r->name, sizeof convbuf);
+			} else
+				(void)snprintf(convbuf, sizeof convbuf,
+				    "REG_0x%x", target);
+			s = convbuf;
+		} else
+			s = r->explain;
+	}
+
+	len = strlen(s) + 1;
+	if (errbuf_size > 0) {
+		llvm_strlcpy(errbuf, s, errbuf_size);
+	}
+
+	return(len);
+}
+
+/*
+ - regatoi - internal routine to implement REG_ATOI
+ */
+static const char *
+regatoi(const llvm_regex_t *preg, char *localbuf, int localbufsize)
+{
+	struct rerr *r;
+
+	for (r = rerrs; r->code != 0; r++)
+		if (strcmp(r->name, preg->re_endp) == 0)
+			break;
+	if (r->code == 0)
+		return("0");
+
+	(void)snprintf(localbuf, localbufsize, "%d", r->code);
+	return(localbuf);
+}