1 files changed, 88 insertions, 0 deletions
diff --git a/src/ipstr.c b/src/ipstr.c
new file mode 100644
index 0000000..5676301
--- /dev/null
+++ b/src/ipstr.c
@@ -0,0 +1,88 @@
+/* grecs - Gray's Extensible Configuration System
+   Copyright (C) 2007-2014 Sergey Poznyakoff
+
+   Grecs 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.
+
+   Grecs 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 Grecs. If not, see <http://www.gnu.org/licenses/>. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+#include <string.h>
+#include <ctype.h>
+#include "grecs.h"
+
+int 
+grecs_str_is_ipv4(const char *addr)
+{
+        int dot_count = 0;
+        int digit_count = 0;
+
+	for (; *addr; addr++) {
+		if (!isascii(*addr))
+			return 0;
+                if (*addr == '.') {
+                        if (++dot_count > 3)
+                                break;
+                        digit_count = 0;
+                } else if (!(isdigit(*addr) && ++digit_count <= 3))
+                        return 0;
+        }
+
+        return (dot_count == 3);
+}
+
+int 
+grecs_str_is_ipv6(const char *addr)
+{
+        int col_count = 0; /* Number of colons */
+	int dcol = 0;      /* Did we encounter a double-colon? */
+	int dig_count = 0; /* Number of digits in the last group */
+	
+	for (; *addr; addr++) {
+		if (!isascii(*addr))
+			return 0;
+		else if (isxdigit(*addr)) {
+			if (++dig_count > 4)
+				return 0;
+		} else if (*addr == ':') {
+			if (col_count && dig_count == 0 && ++dcol > 1)
+				return 0;
+			if (++col_count > 7)
+				return 0;
+			dig_count = 0;
+		} else
+			return 0;
+	}
+
+	return (col_count == 7 || dcol);
+}
+
+int
+grecs_str_is_num(const char *s)
+{
+	for (; *s; ++s)
+		if (!isdigit(*s))
+			return 0;
+	return 1;
+}
+
+int
+grecs_str_is_ipaddr(const char *addr)
+{
+	if (strchr (addr, '.'))
+		return grecs_str_is_ipv4(addr);
+	else if (strchr (addr, ':'))
+		return grecs_str_is_ipv6(addr);
+	return 0;
+}
+