added small regex check tool to repository

This is intended for debugging and considered worth preserving.
However, it has not (yet) been added to the build diag tools
as it is not considered important enough.

1 files changed, 72 insertions, 0 deletions

diff --git a/tools/regexp.c b/tools/regexp.c
new file mode 100644
index 00000000..c8e4c681
--- /dev/null
+++ b/tools/regexp.c
@@ -0,0 +1,72 @@
+/* A simple regular expression checker for rsyslog test and debug.
+ * Regular expressions have shown to turn out to be a hot support topic. 
+ * While I have done an online tool at http://www.rsyslog.com/tool-regex
+ * there are still some situations where one wants to check against the
+ * actual clib api calls. This is what this small test program does,
+ * it takes its command line arguments (re first, then sample data) and
+ * pushes them into the API and then shows the result. This should be
+ * considered the ultimate reference for any questions arising.
+ *
+ * Copyright 2008 Rainer Gerhards and Adiscon GmbH.
+ *
+ * This file is part of rsyslog.
+ *
+ * Rsyslog is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Rsyslog is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Rsyslog.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * A copy of the GPL can be found in the file "COPYING" in this distribution.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <regex.h>
+
+int main(int argc, char *argv[])
+{
+	regex_t preg;
+	size_t nmatch = 10;
+	regmatch_t pmatch[10];
+	char *pstr;
+	int i;
+
+	if(argc != 3) {
+		fprintf(stderr, "usage: regex regexp sample-data\n");
+		exit(1);
+	}
+
+	pstr = strdup(argv[2]); /* get working copy */
+
+	i = regcomp(&preg, argv[1], REG_EXTENDED);
+	printf("regcomp returns %d\n", i);
+	i = regexec(&preg, pstr, nmatch, pmatch, 0);
+	printf("regexec returns %d\n", i);
+	if(i == REG_NOMATCH) {
+		printf("found no match!\n");
+		return 1;
+	}
+
+	printf("returned substrings:\n");
+	for(i = 0 ; i < 10 ; i++) {
+		printf("%d: so %d, eo %d", i, pmatch[i].rm_so, pmatch[i].rm_eo);
+		if(pmatch[i].rm_so != -1) {
+			int j;
+			printf(", text: '");
+			for(j = pmatch[i].rm_so ; j < pmatch[i].rm_eo ; ++j)
+				putchar(pstr[j]);
+			putchar('\'');
+		}
+		putchar('\n');
+	}
+	return 0;
+}