pkt: Initial import

This data type is bound to replace the `(netdev_hlist_t *ulh, void
*data)` tuples in netapi and netdev.

sys/Makefile

@@ -1,3 +1,6 @@
+ifneq (,$(filter pkt,$(USEMODULE)))
+    DIRS += net/crosslayer/pkt
+endif
 ifneq (,$(filter pktbuf,$(USEMODULE)))
     DIRS += net/crosslayer/pktbuf
 endif

sys/include/pkt.h

@@ -0,0 +1,268 @@
+/*
+ * Copyright (C) 2014 Martin Lenders <mlenders@inf.fu-berlin.de>
+ *
+ * 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    pkt Packet
+ * @ingroup     net
+ * @{
+ *
+ * @file    pkt.h
+ * @brief   General definitions for network packets
+ *
+ * @note    This file resides in the `sys` module's include path since it is
+ *          needed for network device drivers and the `sys/net` module's include
+ *          path is not always included (and netdev does not necessarily needs
+ *          to a compiled `pkt`).
+ *
+ * @author  Martine Lenders <mlenders@inf.fu-berlin.de>
+ */
+#ifndef __PKT_H_
+#define __PKT_H_
+
+#include <inttypes.h>
+
+#include "clist.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief   Definition of protocol families to determine the type of the packet
+ *          or which protocols a network device (see @ref netdev) or protocol
+ *          layer (see @ref netapi) can handle
+ *
+ * @note    XXX: The concrete definition of the values is necessary to work
+ *          with super-flexible devices as e.g. @ref native_net. It was also
+ *          decided not to use ethertype since protocols not supplied by it
+ *          might be supported
+ */
+typedef enum {
+    PKT_PROTO_UNKNOWN       = 0x0000,   /**< Type was not specified */
+
+    /**
+     * @brief   Radio frame protocol
+     *
+     * @details Sends frames as defined by radio_packet_t.
+     */
+    PKT_PROTO_RADIO         = 0x0001,
+
+    PKT_PROTO_ETHERNET      = 0x0002,   /**< Ethernet */
+    PKT_PROTO_802154_BEACON = 0x0003,   /**< IEEE 802.15.4 beacon frame */
+    PKT_PROTO_802154_DATA   = 0x0004,   /**< IEEE 802.15.4 data frame */
+    PKT_PROTO_802154_ACK    = 0x0005,   /**< IEEE 802.15.4 acknowledgment frame */
+    PKT_PROTO_802154_MACCMD = 0x0006,   /**< IEEE 802.15.4 MAC command frame */
+    PKT_PROTO_BTLE          = 0x0007,   /**< Bluetooth Low-Energy */
+
+    /**
+     * @brief   CC110x frame format protocol
+     *
+     * @details Sends frames as defined by cc110x_packet_t.
+     */
+    PKT_PROTO_CC110X        = 0x0008,
+    PKT_PROTO_6LOWPAN       = 0x0009,   /**< 6LoWPAN. */
+    PKT_PROTO_IPV4          = 0x000a,   /**< IPv4. */
+    PKT_PROTO_IPV6          = 0x000b,   /**< IPv6. */
+    PKT_PROTO_UDP           = 0x000c,   /**< UDP. */
+    PKT_PROTO_TCP           = 0x000d,   /**< TCP. */
+    PKT_PROTO_CCNL          = 0x000e,   /**< CCN lite. */
+} pkt_proto_t;
+
+/**
+ * @brief   Type to define payload size of a packet
+ */
+typedef uint16_t pktsize_t;
+
+/**
+ * @brief   Macro for pktsize_t printing formatter
+ */
+#define PRIpktsize  PRIu16
+
+/**
+ * @brief   Maximum value for packet size
+ */
+#define PKTSIZE_MAX (UINT16_MAX)
+
+/**
+ * @brief   Circular list type to store a number of protocol headers of
+ *          unspecified type to work with @ref clist.h.
+ *
+ * @note    This type implements its own list implementation because of the way
+ *          it is stored in the packet buffer.
+ */
+typedef struct __attribute__((packed)) pkt_hlist_t {    /* packed to be aligned
+                                                         * correctly in static
+                                                         * packet buffer */
+    struct pkt_hlist_t *next;   /**< next element in list. */
+    void *header_data;          /**< the data of the header */
+    pktsize_t header_len;       /**< the length of the header in byte. */
+    pkt_proto_t header_proto;   /**< protocol of the header. */
+} pkt_hlist_t;
+
+/**
+ * @brief   Type to represent a network packet
+ *
+ * @note    This type has not an initializer on purpose. Please use @ref pktbuf
+ *          as factory.
+ */
+typedef struct __attribute__((packed)) {    /* packed to be aligned correctly
+                                             * in static packet buffer */
+    pkt_hlist_t *headers;       /**< network protocol headers of the packet. */
+    void *payload_data;              /**< payload of the packet. */
+    pktsize_t payload_len;      /**< length of pkt_t::payload. */
+    pkt_proto_t payload_proto;  /**< protocol of pkt_t::payload, if any */
+} pkt_t;
+
+/**
+ * @brief Calculates total length of a list of headers.
+ *
+ * @param[in] list  list of headers.
+ *
+ * @note    The pkt_hlist_t type implements its own list implementation because
+ *          of the way it is stored in the packet buffer.
+ *
+ * @return  length of the list of headers.
+ */
+pktsize_t pkt_hlist_len(pkt_hlist_t *list);
+
+/**
+ * @brief Advance the header list
+ *
+ * @param[in,out] list  The list to work upon.
+ *
+ * @return  The next element in @p list
+ * @return  NULL if list reached its end
+ */
+static inline pkt_hlist_t *pkt_hlist_advance(pkt_hlist_t **list)
+{
+    if (list != NULL && *list != NULL) {
+        *list = (*list)->next;
+        return *list;
+    }
+
+    return NULL;
+}
+
+/**
+ * @brief Adds a new header to a header list.
+ *
+ * @param[in,out] list  The list add the @p header to.
+ * @param[in] header    The header to add to @p list.
+ */
+static inline void pkt_hlist_add(pkt_hlist_t **list, pkt_hlist_t *header)
+{
+    if (header == NULL || list == NULL) {
+        return;
+    }
+
+    header->next = (*list);
+    *list = header;
+}
+
+/**
+ * @brief Removes and return first header from a header list.
+ *
+ * @param[in,out] list  The list remove the @p header from.
+ *
+ * @return The previously first header in @p list.
+ * @return NULL if @p list is empty (aka `== NULL`)
+ */
+pkt_hlist_t *pkt_hlist_remove_first(pkt_hlist_t **list);
+
+/**
+ * @brief Removes a header from a header list.
+ *
+ * @param[in,out] list  The list remove the @p header from.
+ * @param[in] header    The header to remove from @p list.
+ */
+void pkt_hlist_remove(pkt_hlist_t **list, pkt_hlist_t *header);
+
+/**
+ * @brief   Helper function to calculate the total length of the headers of
+ *          @p pkt.
+ *
+ * @note    Wrapper function for @ref pkt_hlist_len()
+ *
+ * @param[in]   pkt   A network packet.
+ *
+ * @return  Length in number of bytes of all headers in pkt::headers.
+ */
+static inline pktsize_t pkt_total_header_len(const pkt_t *pkt)
+{
+    return pkt_hlist_len(pkt->headers);
+}
+
+/**
+ * @brief   Calculate total length of the packet.
+ *
+ * @return  Total length of the packet in number of bytes
+ */
+static inline pktsize_t pkt_total_len(const pkt_t *pkt)
+{
+    return pkt_total_header_len(pkt) + pkt->payload_len;
+}
+
+/**
+ * @brief Adds @p header to packet @p pkt.
+ *
+ * @note    Wrapper function for @ref pkt_hlist_add()
+ *
+ * @param[in,out] pkt   The packet to add @p header to
+ * @param[in] header    The header to add to the list of headers of @p pkt.
+ */
+static inline void pkt_add_header(pkt_t *pkt, pkt_hlist_t *header)
+{
+    if (pkt == NULL) {
+        return;
+    }
+
+    pkt_hlist_add(&(pkt->headers), header);
+}
+
+/**
+ * @brief Removes @p header from packet @p pkt.
+ *
+ * @note    Wrapper function for @ref pkt_hlist_remove()
+ *
+ * @param[in,out] pkt   The packet to remove @p header from. May not be NULL.
+ * @param[in] header    The header to remove from the list of headers of @p pkt.
+ */
+static inline void pkt_remove_header(pkt_t *pkt, pkt_hlist_t *header)
+{
+    if (pkt == NULL) {
+        return;
+    }
+
+    pkt_hlist_remove(&(pkt->headers), header);
+}
+
+/**
+ * @brief Removes first (lowest layer) header from packet @p pkt and returns it.
+ *
+ * @note    Wrapper function for @ref pkt_hlist_remove_first()
+ *
+ * @param[in,out] pkt   The packet to remove @p header from.
+ *
+ * @return The previously first header of @p pkt.
+ * @return NULL if  @p pkt is empty (aka `== NULL`)
+ */
+static inline pkt_hlist_t *pkt_remove_first_header(pkt_t *pkt)
+{
+    if (pkt == NULL) {
+        return NULL;
+    }
+
+    return pkt_hlist_remove_first(&(pkt->headers));
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __PKT_H_ */
+/** @} */

sys/net/crosslayer/pkt/Makefile

@@ -0,0 +1 @@
+include $(RIOTBASE)/Makefile.base

sys/net/crosslayer/pkt/pkt.c

@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2014 Martin Lenders <mlenders@inf.fu-berlin.de>
+ *
+ * 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.
+ */
+
+/**
+ * @{
+ *
+ * @file    pkt.c
+ */
+
+#include "pkt.h"
+
+pktsize_t pkt_hlist_len(pkt_hlist_t *list)
+{
+    pktsize_t len = 0;
+
+    while (list) {
+        len += list->header_len;
+        pkt_hlist_advance(&list);
+    }
+
+    return len;
+}
+
+pkt_hlist_t *pkt_hlist_remove_first(pkt_hlist_t **list)
+{
+    pkt_hlist_t *res;
+
+    if (list == NULL || *list == NULL) {
+        return NULL;
+    }
+
+    res = *list;
+    *list = res->next;
+    res->next = NULL;
+
+    return res;
+}
+
+void pkt_hlist_remove(pkt_hlist_t **list, pkt_hlist_t *header)
+{
+    if (list == NULL || *list == NULL || header == NULL) {
+        return;
+    }
+
+    if ((*list) == header) {
+        pkt_hlist_remove_first(list);
+    }
+    else {
+        pkt_hlist_t *ptr = (*list)->next, *prev = *list;
+
+        while (ptr != NULL) {
+            if (ptr == header) {
+                prev->next = ptr->next;
+                ptr->next = NULL;
+            }
+
+            pkt_hlist_advance(&ptr);
+            pkt_hlist_advance(&prev);
+        }
+    }
+
+}
+
+/** @} */