sys/bitfield: add support for bitfield operations

sys/include/bitfield.h

@@ -89,6 +89,65 @@ static inline bool bf_isset(uint8_t field[], size_t idx)
     return (field[idx / 8] & (1u << (7 - (idx % 8))));
 }
 
+/**
+ * @brief  Perform a bitwise OR operation on two bitfields
+ *         `out = a | b`
+ *
+ * @param[out]    out   The resulting bitfield
+ * @param[in]     a     The first bitfield
+ * @param[in]     b     The second bitfield
+ */
+static inline void bf_or(uint8_t out[], const uint8_t a[], const uint8_t b[], size_t len)
+{
+    while (len--) {
+        out[len] = a[len] | b[len];
+    }
+}
+
+/**
+ * @brief  Perform a bitwise AND operation on two bitfields
+ *         `out = a & b`
+ *
+ * @param[out]    out   The resulting bitfield
+ * @param[in]     a     The first bitfield
+ * @param[in]     b     The second bitfield
+ */
+static inline void bf_and(uint8_t out[], const uint8_t a[], const uint8_t b[], size_t len)
+{
+    while (len--) {
+        out[len] = a[len] & b[len];
+    }
+}
+
+/**
+ * @brief  Perform a bitwise XOR operation on two bitfields
+ *         `out = a ^ b`
+ *
+ * @param[out]    out   The resulting bitfield
+ * @param[in]     a     The first bitfield
+ * @param[in]     b     The second bitfield
+ */
+static inline void bf_xor(uint8_t out[], const uint8_t a[], const uint8_t b[], size_t len)
+{
+    while (len--) {
+        out[len] = a[len] ^ b[len];
+    }
+}
+
+/**
+ * @brief  Perform a bitwise NOT operation on a bitfield
+ *         `out = ~a`
+ *
+ * @param[out]    out   The resulting bitfield
+ * @param[in]     a     The bitfield to invert
+ */
+static inline void bf_inv(uint8_t out[], const uint8_t a[], size_t len)
+{
+    while (len--) {
+        out[len] = ~a[len];
+    }
+}
+
 /**
  * @brief  Atomically get the number of an unset bit and set it
  *