1 files changed, 50 insertions, 0 deletions
diff --git a/util.c b/util.c
new file mode 100644
index 0000000..8ab720f
--- /dev/null
+++ b/util.c
@@ -0,0 +1,50 @@
+/*
+ * Copyright 2012 (C) Christian Franke <nobody at nowhere dot ws>
+ *
+ * This program 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.
+ *
+ * This program 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 This program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "util.h"
+
+uint8_t parse_hex_char(char input)
+{
+	if (input >= '0' && input <= '9')
+		return input - '0';
+
+	if (input >= 'A' && input <= 'F')
+		return 10 + input - 'A';
+
+	if (input >= 'a' && input <= 'f')
+		return 10 + input - 'a';
+
+	return -1;
+}
+
+uint8_t parse_hex_number(char *buffer, uint8_t *target)
+{
+	uint8_t rv;
+
+	rv = parse_hex_char(buffer[0]);
+	if (rv == -1)
+		return 1;
+	*target = rv << 4;
+
+	rv = parse_hex_char(buffer[1]);
+	if (rv == -1)
+		return 1;
+	*target += rv;
+
+	return 0;
+}