1 files changed, 29 insertions, 0 deletions
diff --git a/common/bbs/string.c b/common/bbs/string.c
index 60b03b37..22c93abb 100644
--- a/common/bbs/string.c
+++ b/common/bbs/string.c
@@ -1,6 +1,8 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <assert.h>
+#include <ctype.h>
 #include "cmbbs.h"
 
 void obfuscate_ipstr(char *s)
@@ -12,3 +14,30 @@ void obfuscate_ipstr(char *s)
     *s++ = '*';
     *s = 0;
 }
+
+bool
+is_valid_brdname(const char *brdname)
+{
+    int i;
+    char ch;
+    int len;
+
+    assert(brdname);
+
+    len = strlen(brdname);
+    if (len < 2 || len > IDLEN)
+	return false;
+
+    for (i = 0; i < len; i++) {
+	char ch = brdname[i];
+	if (i == 0) {
+	    if (!isalpha((int)ch))
+		return false;
+	} else {
+	    if (!isalnum(ch) && ch != '_' && ch != '-' && ch != '.')
+		return false;
+	}
+    }
+    return true;
+}
+