text: /*
   * Copyright (c) 2010, Swedish Institute of Computer Science.
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. Neither the name of the Institute nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   *
   * This file is part of the Contiki operating system.
   *
   * \file
   *	Public API declarations for ContikiRPL.
   * \author
   *	Joakim Eriksson <joakime@sics.se> & Nicolas Tsiftes <nvt@sics.se>
   *
   */
  
  #ifndef RPL_H
  #define RPL_H
  
  #include "rpl-conf.h"
  
  #include "lib/list.h"
  #include "net/uip.h"
  #include "net/uip-ds6.h"
  #include "sys/ctimer.h"
  
  /*---------------------------------------------------------------------------*/
  /* The amount of parents that this node has in a particular DAG. */
  #define RPL_PARENT_COUNT(dag)   list_length((dag)->parents)
  /*---------------------------------------------------------------------------*/
  typedef uint16_t rpl_rank_t;
  typedef uint16_t rpl_ocp_t;
  /*---------------------------------------------------------------------------*/
  /* DAG Metric Container Object Types, to be confirmed by IANA. */
  #define RPL_DAG_MC_NONE			0 /* Local identifier for empty MC */
  #define RPL_DAG_MC_NSA                  1 /* Node State and Attributes */
  #define RPL_DAG_MC_ENERGY               2 /* Node Energy */
  #define RPL_DAG_MC_HOPCOUNT             3 /* Hop Count */
  #define RPL_DAG_MC_THROUGHPUT           4 /* Throughput */
  #define RPL_DAG_MC_LATENCY              5 /* Latency */
  #define RPL_DAG_MC_LQL                  6 /* Link Quality Level */
  #define RPL_DAG_MC_ETX                  7 /* Expected Transmission Count */
  #define RPL_DAG_MC_LC                   8 /* Link Color */
  
  /* DAG Metric Container flags. */
  #define RPL_DAG_MC_FLAG_P               0x8
  #define RPL_DAG_MC_FLAG_C               0x4
  #define RPL_DAG_MC_FLAG_O               0x2
  #define RPL_DAG_MC_FLAG_R               0x1
  
  /* DAG Metric Container aggregation mode. */
  #define RPL_DAG_MC_AGGR_ADDITIVE        0
  #define RPL_DAG_MC_AGGR_MAXIMUM         1
  #define RPL_DAG_MC_AGGR_MINIMUM         2
  #define RPL_DAG_MC_AGGR_MULTIPLICATIVE  3
  
  /* The bit index within the flags field of
     the rpl_metric_object_energy structure. */
  #define RPL_DAG_MC_ENERGY_INCLUDED	3
  #define RPL_DAG_MC_ENERGY_TYPE		1
  #define RPL_DAG_MC_ENERGY_ESTIMATION	0
  
  #define RPL_DAG_MC_ENERGY_TYPE_MAINS		0
  #define RPL_DAG_MC_ENERGY_TYPE_BATTERY		1
  #define RPL_DAG_MC_ENERGY_TYPE_SCAVENGING	2
  
  struct rpl_metric_object_energy {
    uint8_t flags;
    uint8_t energy_est;
  };
  
  /* Logical representation of a DAG Metric Container. */
  struct rpl_metric_container {
    uint8_t type;
    uint8_t flags;
    uint8_t aggr;
    uint8_t prec;
    uint8_t length;
    union metric_object {
      struct rpl_metric_object_energy energy;
      uint16_t etx;
    } obj;
  };
  typedef struct rpl_metric_container rpl_metric_container_t;
  /*---------------------------------------------------------------------------*/
  struct rpl_instance;
  struct rpl_dag;
  /*---------------------------------------------------------------------------*/
  struct rpl_parent {
    struct rpl_parent *next;
    struct rpl_dag *dag;
    rpl_metric_container_t mc;
    uip_ipaddr_t addr;
    rpl_rank_t rank;
    uint8_t link_metric;
    uint8_t dtsn;
    uint8_t updated;
  };
  typedef struct rpl_parent rpl_parent_t;
  /*---------------------------------------------------------------------------*/
  /* RPL DIO prefix suboption */
  struct rpl_prefix {
    uip_ipaddr_t prefix;
    uint32_t lifetime;
    uint8_t length;
    uint8_t flags;
  };
  typedef struct rpl_prefix rpl_prefix_t;
  /*---------------------------------------------------------------------------*/
  /* Directed Acyclic Graph */
  struct rpl_dag {
    uip_ipaddr_t dag_id;
    rpl_rank_t min_rank; /* should be reset per DAG iteration! */
    uint8_t version;
    uint8_t grounded;
    uint8_t preference;
    uint8_t used;
    /* live data for the DAG */
    uint8_t joined;
    rpl_parent_t *preferred_parent;
    rpl_rank_t rank;
    struct rpl_instance *instance;
    LIST_STRUCT(parents);
    rpl_prefix_t prefix_info;
  };
  typedef struct rpl_dag rpl_dag_t;
  typedef struct rpl_instance rpl_instance_t;
  /*---------------------------------------------------------------------------*/
  /*
   * API for RPL objective functions (OF)
   *
   * reset(dag)
   *
   *  Resets the objective function state for a specific DAG. This function is
   *  called when doing a global repair on the DAG.
   *
   * parent_state_callback(parent, known, etx)
   *
   *  Receives link-layer neighbor information. The parameter "known" is set
   *  either to 0 or 1. The "etx" parameter specifies the current
   *  ETX(estimated transmissions) for the neighbor.
   *
   * best_parent(parent1, parent2)
   *
   *  Compares two parents and returns the best one, according to the OF.
   *
   * best_dag(dag1, dag2)
   *
   *  Compares two DAGs and returns the best one, according to the OF.
   *
   * calculate_rank(parent, base_rank)
   *
   *  Calculates a rank value using the parent rank and a base rank.
   *  If "parent" is NULL, the objective function selects a default increment
   *  that is adds to the "base_rank". Otherwise, the OF uses information known
   *  about "parent" to select an increment to the "base_rank".
   *
   * update_metric_container(dag)
   *
   *  Updates the metric container for outgoing DIOs in a certain DAG.
   *  If the objective function of the DAG does not use metric containers, 
   *  the function should set the object type to RPL_DAG_MC_NONE.
   */
  struct rpl_of {
    void (*reset)(struct rpl_dag *);
    void (*parent_state_callback)(rpl_parent_t *, int, int);
    rpl_parent_t *(*best_parent)(rpl_parent_t *, rpl_parent_t *);
    rpl_dag_t *(*best_dag)(rpl_dag_t *, rpl_dag_t *);
    rpl_rank_t (*calculate_rank)(rpl_parent_t *, rpl_rank_t);
    void (*update_metric_container)( rpl_instance_t *);
    rpl_ocp_t ocp;
  };
  typedef struct rpl_of rpl_of_t;
  /*---------------------------------------------------------------------------*/
  /* Instance */
  struct rpl_instance {
    /* DAG configuration */
    rpl_metric_container_t mc;
    rpl_of_t *of;
    rpl_dag_t *current_dag;
    rpl_dag_t dag_table[RPL_MAX_DAG_PER_INSTANCE];
    /* The current default router - used for routing "upwards" */
    uip_ds6_defrt_t *def_route;
    uint8_t instance_id;
    uint8_t used;
    uint8_t dtsn_out;
    uint8_t mop;
    uint8_t dio_intdoubl;
    uint8_t dio_intmin;
    uint8_t dio_redundancy;
    uint8_t default_lifetime;
    uint8_t dio_intcurrent;
    uint8_t dio_send; /* for keeping track of which mode the timer is in */
    uint8_t dio_counter;
    rpl_rank_t max_rankinc;
    rpl_rank_t min_hoprankinc;
    uint16_t lifetime_unit; /* lifetime in seconds = l_u * d_l */
  #if RPL_CONF_STATS
    uint16_t dio_totint;
    uint16_t dio_totsend;
    uint16_t dio_totrecv;
  #endif /* RPL_CONF_STATS */
    clock_time_t dio_next_delay; /* delay for completion of dio interval */
    struct ctimer dio_timer;
    struct ctimer dao_timer;
  };
  
  /*---------------------------------------------------------------------------*/
  /* Public RPL functions. */
  void rpl_init(void);
  void uip_rpl_input(void);
  rpl_dag_t *rpl_set_root(uint8_t instance_id, uip_ipaddr_t * dag_id);
  int rpl_set_prefix(rpl_dag_t *dag, uip_ipaddr_t *prefix, unsigned len);
  int rpl_repair_root(uint8_t instance_id);
  int rpl_set_default_route(rpl_instance_t *instance, uip_ipaddr_t *from);
  rpl_dag_t *rpl_get_any_dag(void);
  rpl_instance_t *rpl_get_instance(uint8_t instance_id);
  void rpl_update_header_empty(void);
  int rpl_update_header_final(uip_ipaddr_t *addr);
  int rpl_verify_header(int);
  void rpl_remove_header(void);
  uint8_t rpl_invert_header(void);
  /*---------------------------------------------------------------------------*/
  #endif /* RPL_H */
  