net: added generic network interface header format

sys/include/net/ng_netif/hdr.h

@@ -0,0 +1,141 @@
+/*
+ * Copyright (C) 2015 Freie Universität Berlin
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @defgroup    net_netif_hdr Generic network interface header
+ * @ingroup     net_netif
+ * @{
+ *
+ * @file
+ * @brief       Generic network interface header
+ *
+ * @author      Hauke Petersen <hauke.petersen@fu-berlin.de>
+ */
+
+#ifndef NETIF_HDR_H_
+#define NETIF_HDR_H_
+
+#include <string.h>
+#include <stdint.h>
+
+#include "kernel.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief   Generic network interface header
+ *
+ * The link layer addresses included in this header are put in memory directly
+ * following this struct.
+ */
+typedef struct __attribute__((packed)) {
+    uint8_t src_l2addr_len;     /**< length of l2 source address in byte */
+    uint8_t dst_l2addr_len;     /**< length of l2 destination address in byte */
+    kernel_pid_t if_pid;        /**< PID of network interface */
+    uint8_t rssi;               /**< rssi of received packet (optional) */
+    uint8_t lqi;                /**< lqi of received packet (optional) */
+} ng_netif_hdr_t;
+
+/**
+ * @brief   Initialize the given generic network interface header
+ *
+ * @param[in] hdr               header to initialize
+ * @param[in] src_l2addr_len    link layer source address length
+ * @param[in] dst_l2addr_len    link layer destination address length
+ */
+inline void ng_netif_hdr_init(ng_netif_hdr_t *hdr, uint8_t src_l2addr_len,
+                          uint8_t dst_l2addr_len)
+{
+    hdr->src_l2addr_len = src_l2addr_len;
+    hdr->dst_l2addr_len = dst_l2addr_len;
+    hdr->if_pid = KERNEL_PID_UNDEF;
+    hdr->rssi = 0;
+    hdr->lqi = 0;
+}
+
+/**
+ * @brief   Get the size of the given generic network interface header
+ *
+ * @param[in] hdr           header to get the size of
+ *
+ * @return                  the size of the given header, including link layer
+ *                          addresses
+ */
+inline size_t ng_netif_hdr_sizeof(ng_netif_hdr_t *hdr)
+{
+    return sizeof(ng_netif_hdr_t) + hdr->src_l2addr_len + hdr->dst_l2addr_len;
+}
+
+/**
+ * @brief   Get the source address from the given header
+ *
+ * @param[in] hdr           header to read from
+ *
+ * @return                  pointer to source address on success
+ * @return                  NULL on error
+ */
+inline uint8_t *ng_netif_hdr_get_src_addr(ng_netif_hdr_t *hdr)
+{
+    return ((uint8_t *)hdr) + sizeof(ng_netif_hdr_t);
+}
+
+/**
+ * @brief   Set the source address in the given header
+ *
+ * @param[in] hdr           header to write to
+ * @param[in] addr          new source address
+ * @param[in] addr_len      *addr* length
+ */
+inline void ng_netif_hdr_set_src_addr(ng_netif_hdr_t *hdr, uint8_t *addr,
+                                  uint8_t addr_len)
+{
+    if (addr_len != hdr->src_l2addr_len) {
+        return;
+    }
+    memcpy(((uint8_t *)hdr) + sizeof(ng_netif_hdr_t), addr, addr_len);
+}
+
+
+/**
+ * @brief   Get the destination address from the given header
+ *
+ * @param[in] hdr           header to read from
+ *
+ * @return                  pointer to destination address on success
+ * @return                  NULL on error
+ */
+inline uint8_t *ng_netif_hdr_get_dst_addr(ng_netif_hdr_t *hdr)
+{
+    return ((uint8_t *)hdr) + sizeof(ng_netif_hdr_t) + hdr->src_l2addr_len;
+}
+
+/**
+ * @brief   Set the destination address in the given header
+ *
+ * @param[in] hdr           header to write to
+ * @param[in] addr          new destination address
+ * @param[in] addr_len      *addr* length
+ */
+inline void ng_netif_hdr_set_dst_addr(ng_netif_hdr_t *hdr, uint8_t *addr,
+                                  uint8_t addr_len)
+{
+    if (addr_len != hdr->dst_l2addr_len) {
+        return;
+    }
+    memcpy(((uint8_t *)hdr) + sizeof(ng_netif_hdr_t) + hdr->dst_l2addr_len,
+           addr, addr_len);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* NETIF_HDR_H_ */
+/** @} */