Added function to do prefix wildcard comparison for filtering.

[trust_router.git] / common / tr_filter.c

diff --git a/common/tr_filter.c b/common/tr_filter.c
new file mode 100644 (file)
index 0000000..857ac5b
--- /dev/null
+++ b/common/tr_filter.c
@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 2012, 2013, JANET(UK)
+ * All rights reserved.
+ *
+ * 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 JANET(UK) 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 COPYRIGHT HOLDERS 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
+ * COPYRIGHT HOLDER 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.
+ *
+ */
+
+#include <string.h>
+#include <tr_filter.h>
+
+/* Returns TRUE (1) if the the string (str) matchs the wildcard string (wc_str), FALSE (0) if not.
+ */
+int tr_prefix_wildcard_match (char *str, char *wc_str) {
+  char *wc_post = wc_str;
+  size_t len = 0;
+  size_t wc_len = 0;
+
+  if ((!str) || (!wc_str))
+    return 0;
+
+  /* TBD -- skip leading white space? */
+  if ('*' == wc_str[0])
+    wc_post = &(wc_str[1]);
+
+  len = strlen(str);
+  /* Everything matches an empty string or "*" */
+  if (0 == (wc_len = strlen(wc_post))) 
+    return 1;
+  if (wc_len > len)
+    return 0;
+
+  if (!strcmp(&(str[len-wc_len]), wc_post)) {
+    return 1;
+  }
+  else
+    return 0;
+  }