1 files changed, 43 insertions, 0 deletions
diff --git a/appl/lib/encoding/base16.b b/appl/lib/encoding/base16.b
new file mode 100644
index 00000000..6c91c200
--- /dev/null
+++ b/appl/lib/encoding/base16.b
@@ -0,0 +1,43 @@
+implement Encoding;
+
+include "encoding.m";
+
+hex: con "0123456789ABCDEF";
+
+enc(a: array of byte): string
+{
+	o: string;
+	for(i := 0; i < len a; i++){
+		n := int a[i];
+		o[len o] = hex[n>>4];
+		o[len o] = hex[n & 16rF];
+	}
+	return o;
+}
+
+dec(s: string): array of byte
+{
+	a := array[(len s+1)/2] of byte;	# upper bound
+	o := 0;
+	j := 0;
+	n := 0;
+	for(i := 0; i < len s; i++){
+		c := s[i];
+		n <<= 4;
+		case c {
+		'0' to '9' =>
+			n |= c-'0';
+		'A' to 'F' =>
+			n |= c-'A'+10;
+		'a' to 'f' =>
+			n |= c-'a'+10;
+		* =>
+			continue;
+		}
+		if(++j == 2){
+			a[o++] = byte n;
+			j = n = 0;
+		}
+	}
+	return a[0:o];
+}