text: /*
   * Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The OpenAirInterface Software Alliance licenses this file to You under
   * the OAI Public License, Version 1.1  (the "License"); you may not use this file
   * except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.openairinterface.org/?page_id=698
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   *-------------------------------------------------------------------------------
   * For more information about the OpenAirInterface (OAI) Software Alliance:
   *      contact@openairinterface.org
   */
  
  /*
                                  enb_app.c
                               -------------------
    AUTHOR  : Laurent Winckel, Sebastien ROUX, Lionel GAUTHIER, Navid Nikaein
    COMPANY : EURECOM
    EMAIL   : Lionel.Gauthier@eurecom.fr and Navid Nikaein
  */
  
  #include <string.h>
  #include <stdio.h>
  
  #include "enb_app.h"
  #include "enb_config.h"
  #include "assertions.h"
  #include "common/ran_context.h"
  
  #include "common/utils/LOG/log.h"
  
  #if defined(ENABLE_ITTI)
  # include "intertask_interface.h"
  # if defined(ENABLE_USE_MME)
  #   include "s1ap_eNB.h"
  #   include "sctp_eNB_task.h"
  #   include "gtpv1u_eNB_task.h"
  /* temporary warning removale while implementing noS1 */
  /* as config option                                   */
  #   else
  #     ifdef EPC_MODE_ENABLED
  #       undef  EPC_MODE_ENABLED
  #     endif
  #     define EPC_MODE_ENABLED 0
  #   endif
  #   include "x2ap_eNB.h"
  #   include "x2ap_messages_types.h"
  #   define X2AP_ENB_REGISTER_RETRY_DELAY   10
  
  #include "openair1/PHY/INIT/phy_init.h"
  extern unsigned char NB_eNB_INST;
  #endif
  
  extern RAN_CONTEXT_t RC;
  
  #if defined(ENABLE_ITTI)
  
  /*------------------------------------------------------------------------------*/
  # if defined(ENABLE_USE_MME)
  #   define ENB_REGISTER_RETRY_DELAY 10
  # endif
  
  #include "targets/RT/USER/lte-softmodem.h"
  
  /*------------------------------------------------------------------------------*/
  
  /*
  static void configure_phy(module_id_t enb_id, const Enb_properties_array_t* enb_properties)
  {
    MessageDef *msg_p;
    int CC_id;
  
    msg_p = itti_alloc_new_message (TASK_ENB_APP, PHY_CONFIGURATION_REQ);
  
    for (CC_id=0; CC_id<MAX_NUM_CCs; CC_id++) {
      PHY_CONFIGURATION_REQ (msg_p).frame_type[CC_id]              = enb_properties->properties[enb_id]->frame_type[CC_id];
      PHY_CONFIGURATION_REQ (msg_p).prefix_type[CC_id]             = enb_properties->properties[enb_id]->prefix_type[CC_id];
      PHY_CONFIGURATION_REQ (msg_p).downlink_frequency[CC_id]      = enb_properties->properties[enb_id]->downlink_frequency[CC_id];
      PHY_CONFIGURATION_REQ (msg_p).uplink_frequency_offset[CC_id] = enb_properties->properties[enb_id]->uplink_frequency_offset[CC_id];
      PHY_CONFIGURATION_REQ (msg_p).nb_antennas_tx[CC_id]          = enb_properties->properties[enb_id]->nb_antennas_tx[CC_id];
      PHY_CONFIGURATION_REQ (msg_p).nb_antennas_rx[CC_id]          = enb_properties->properties[enb_id]->nb_antennas_rx[CC_id];
      PHY_CONFIGURATION_REQ (msg_p).tx_gain[CC_id]                 = enb_properties->properties[enb_id]->tx_gain[CC_id];
      PHY_CONFIGURATION_REQ (msg_p).rx_gain[CC_id]                 = enb_properties->properties[enb_id]->rx_gain[CC_id];
    }
  
    itti_send_msg_to_task (TASK_PHY_ENB, ENB_MODULE_ID_TO_INSTANCE(enb_id), msg_p);
  }
  */
  
  /*------------------------------------------------------------------------------*/
  static void configure_rrc(uint32_t enb_id)
  {
    MessageDef *msg_p = NULL;
    //  int CC_id;
  
    msg_p = itti_alloc_new_message (TASK_ENB_APP, RRC_CONFIGURATION_REQ);
  
    if (RC.rrc[enb_id]) {
      RCconfig_RRC(msg_p,enb_id, RC.rrc[enb_id]);
      
  
      LOG_I(ENB_APP,"Sending configuration message to RRC task\n");
      itti_send_msg_to_task (TASK_RRC_ENB, ENB_MODULE_ID_TO_INSTANCE(enb_id), msg_p);
  
    }
    else AssertFatal(0,"RRC context for eNB %d not allocated\n",enb_id);
  }
  
  /*------------------------------------------------------------------------------*/
  # if defined(ENABLE_USE_MME)
  static uint32_t eNB_app_register(uint32_t enb_id_start, uint32_t enb_id_end)//, const Enb_properties_array_t *enb_properties)
  {
    uint32_t         enb_id;
    MessageDef      *msg_p;
    uint32_t         register_enb_pending = 0;
  
    for (enb_id = enb_id_start; (enb_id < enb_id_end) ; enb_id++) {
      {
        /* note:  there is an implicit relationship between the data structure and the message name */
        msg_p = itti_alloc_new_message (TASK_ENB_APP, S1AP_REGISTER_ENB_REQ);
  
        RCconfig_S1(msg_p, enb_id);
  
        if (enb_id == 0) RCconfig_gtpu();
  
        LOG_I(ENB_APP,"default drx %d\n",((S1AP_REGISTER_ENB_REQ(msg_p)).default_drx));
  
        LOG_I(ENB_APP,"[eNB %d] eNB_app_register for instance %d\n", enb_id, ENB_MODULE_ID_TO_INSTANCE(enb_id));
  
        itti_send_msg_to_task (TASK_S1AP, ENB_MODULE_ID_TO_INSTANCE(enb_id), msg_p);
  
        register_enb_pending++;
      }
    }
  
    return register_enb_pending;
  }
  # endif
  #endif
  
  /*------------------------------------------------------------------------------*/
  static uint32_t eNB_app_register_x2(uint32_t enb_id_start, uint32_t enb_id_end)
  {
    uint32_t         enb_id;
    MessageDef      *msg_p;
    uint32_t         register_enb_x2_pending = 0;
  
    for (enb_id = enb_id_start; (enb_id < enb_id_end) ; enb_id++) {
  
      {
  
        msg_p = itti_alloc_new_message (TASK_ENB_APP, X2AP_REGISTER_ENB_REQ);
  
        RCconfig_X2(msg_p, enb_id);
  
        itti_send_msg_to_task (TASK_X2AP, ENB_MODULE_ID_TO_INSTANCE(enb_id), msg_p);
  
        register_enb_x2_pending++;
      }
    }
  
    return register_enb_x2_pending;
  }
  
  /*------------------------------------------------------------------------------*/
  void *eNB_app_task(void *args_p)
  {
  #if defined(ENABLE_ITTI)
    uint32_t                        enb_nb = RC.nb_inst; 
    uint32_t                        enb_id_start = 0;
    uint32_t                        enb_id_end = enb_id_start + enb_nb;
  # if defined(ENABLE_USE_MME)
    uint32_t                        register_enb_pending=0;
    uint32_t                        registered_enb;
    long                            enb_register_retry_timer_id;
  # endif
    uint32_t                        x2_register_enb_pending;
    uint32_t                        x2_registered_enb;
    long                            x2_enb_register_retry_timer_id;
    uint32_t                        enb_id;
    MessageDef                     *msg_p           = NULL;
    instance_t                      instance;
    int                             result;
    /* for no gcc warnings */
    (void)instance;
  
    itti_mark_task_ready (TASK_ENB_APP);
  
    LOG_I(PHY, "%s() Task ready initialise structures\n", __FUNCTION__);
  
    RCconfig_L1();
  
    RCconfig_macrlc();
  
    LOG_I(PHY, "%s() RC.nb_L1_inst:%d\n", __FUNCTION__, RC.nb_L1_inst);
  
    if (RC.nb_L1_inst>0) AssertFatal(l1_north_init_eNB()==0,"could not initialize L1 north interface\n");
  
    AssertFatal (enb_nb <= RC.nb_inst,
                 "Number of eNB is greater than eNB defined in configuration file (%d/%d)!",
                 enb_nb, RC.nb_inst);
  
    LOG_I(ENB_APP,"Allocating eNB_RRC_INST for %d instances\n",RC.nb_inst);
  
    RC.rrc = (eNB_RRC_INST **)malloc(RC.nb_inst*sizeof(eNB_RRC_INST *));
    LOG_I(PHY, "%s() RC.nb_inst:%d RC.rrc:%p\n", __FUNCTION__, RC.nb_inst, RC.rrc);
  
    for (enb_id = enb_id_start; (enb_id < enb_id_end) ; enb_id++) {
      RC.rrc[enb_id] = (eNB_RRC_INST*)malloc(sizeof(eNB_RRC_INST));
      LOG_I(PHY, "%s() Creating RRC instance RC.rrc[%d]:%p (%d of %d)\n", __FUNCTION__, enb_id, RC.rrc[enb_id], enb_id+1, enb_id_end);
      memset((void *)RC.rrc[enb_id],0,sizeof(eNB_RRC_INST));
      configure_rrc(enb_id);
    }
  
  # if defined(ENABLE_USE_MME)
    /* Try to register each eNB */
      registered_enb = 0;
      register_enb_pending = eNB_app_register (enb_id_start, enb_id_end);//, enb_properties_p);
  #else
    /* Start L2L1 task */
      msg_p = itti_alloc_new_message(TASK_ENB_APP, INITIALIZE_MESSAGE);
      itti_send_msg_to_task(TASK_L2L1, INSTANCE_DEFAULT, msg_p);
  #endif
  
    /* Try to register each eNB with each other */
    x2_registered_enb = 0;
    x2_register_enb_pending = eNB_app_register_x2 (enb_id_start, enb_id_end);
  
    do {
      // Wait for a message
      itti_receive_msg (TASK_ENB_APP, &msg_p);
  
      instance = ITTI_MSG_INSTANCE (msg_p);
  
      switch (ITTI_MSG_ID(msg_p)) {
      case TERMINATE_MESSAGE:
        LOG_W(ENB_APP, " *** Exiting ENB_APP thread\n");
        itti_exit_task ();
        break;
  
      case MESSAGE_TEST:
        LOG_I(ENB_APP, "Received %s\n", ITTI_MSG_NAME(msg_p));
        break;
  
      case SOFT_RESTART_MESSAGE:
        handle_reconfiguration(instance);
        break;
  
      case S1AP_REGISTER_ENB_CNF:
  # if defined(ENABLE_USE_MME)
    	LOG_I(ENB_APP, "[eNB %d] Received %s: associated MME %d\n", instance, ITTI_MSG_NAME (msg_p),
    	      S1AP_REGISTER_ENB_CNF(msg_p).nb_mme);
  
    	DevAssert(register_enb_pending > 0);
    	register_enb_pending--;
  
    	/* Check if at least eNB is registered with one MME */
    	if (S1AP_REGISTER_ENB_CNF(msg_p).nb_mme > 0) {
    	  registered_enb++;
    	}
  
    	/* Check if all register eNB requests have been processed */
    	if (register_enb_pending == 0) {
    	  if (registered_enb == enb_nb) {
    	    /* If all eNB are registered, start L2L1 task */
    	    MessageDef *msg_init_p;
  
    	    msg_init_p = itti_alloc_new_message (TASK_ENB_APP, INITIALIZE_MESSAGE);
    	    itti_send_msg_to_task (TASK_L2L1, INSTANCE_DEFAULT, msg_init_p);
  
    	  } else {
    	    LOG_W(ENB_APP, " %d eNB not associated with a MME, retrying registration in %d seconds ...\n",
    		  enb_nb - registered_enb,  ENB_REGISTER_RETRY_DELAY);
  
    	    /* Restart the eNB registration process in ENB_REGISTER_RETRY_DELAY seconds */
    	    if (timer_setup (ENB_REGISTER_RETRY_DELAY, 0, TASK_ENB_APP, INSTANCE_DEFAULT, TIMER_ONE_SHOT,
    			     NULL, &enb_register_retry_timer_id) < 0) {
    	      LOG_E(ENB_APP, " Can not start eNB register retry timer, use \"sleep\" instead!\n");
  
    	      sleep(ENB_REGISTER_RETRY_DELAY);
    	      /* Restart the registration process */
    	      registered_enb = 0;
    	      register_enb_pending = eNB_app_register (enb_id_start, enb_id_end);//, enb_properties_p);
    	    }
    	  }
    	}
  #endif
        break;
  
      case S1AP_DEREGISTERED_ENB_IND:
        if (EPC_MODE_ENABLED) {
    	LOG_W(ENB_APP, "[eNB %d] Received %s: associated MME %d\n", instance, ITTI_MSG_NAME (msg_p),
    	      S1AP_DEREGISTERED_ENB_IND(msg_p).nb_mme);
  
    	/* TODO handle recovering of registration */
        }
        break;
  
      case TIMER_HAS_EXPIRED:
  # if defined(ENABLE_USE_MME)
        LOG_I(ENB_APP, " Received %s: timer_id %ld\n", ITTI_MSG_NAME (msg_p), TIMER_HAS_EXPIRED(msg_p).timer_id);
  
        if (TIMER_HAS_EXPIRED (msg_p).timer_id == enb_register_retry_timer_id) {
          /* Restart the registration process */
          registered_enb = 0;
          register_enb_pending = eNB_app_register (enb_id_start, enb_id_end);//, enb_properties_p);
        }
  
        if (TIMER_HAS_EXPIRED (msg_p).timer_id == x2_enb_register_retry_timer_id) {
          /* Restart the registration process */
  	x2_registered_enb = 0;
          x2_register_enb_pending = eNB_app_register_x2 (enb_id_start, enb_id_end);
        }
  # endif
        break;
  
      case X2AP_DEREGISTERED_ENB_IND:
        LOG_W(ENB_APP, "[eNB %d] Received %s: associated eNB %d\n", instance, ITTI_MSG_NAME (msg_p),
              X2AP_DEREGISTERED_ENB_IND(msg_p).nb_x2);
  
        /* TODO handle recovering of registration */
        break;
  
      case X2AP_REGISTER_ENB_CNF:
        LOG_I(ENB_APP, "[eNB %d] Received %s: associated eNB %d\n", instance, ITTI_MSG_NAME (msg_p),
              X2AP_REGISTER_ENB_CNF(msg_p).nb_x2);
  
        DevAssert(x2_register_enb_pending > 0);
        x2_register_enb_pending--;
  
        /* Check if at least eNB is registered with one target eNB */
        if (X2AP_REGISTER_ENB_CNF(msg_p).nb_x2 > 0) {
          x2_registered_enb++;
        }
  
        /* Check if all register eNB requests have been processed */
        if (x2_register_enb_pending == 0) {
          if (x2_registered_enb == enb_nb) {
            /* If all eNB are registered, start RRC HO task */
  
  	}else {
            uint32_t x2_not_associated = enb_nb - x2_registered_enb;
  
            LOG_W(ENB_APP, " %d eNB %s not associated with the target\n",
                  x2_not_associated, x2_not_associated > 1 ? "are" : "is");
  	  // timer to retry
  	  /* Restart the eNB registration process in ENB_REGISTER_RETRY_DELAY seconds */
            if (timer_setup (X2AP_ENB_REGISTER_RETRY_DELAY, 0, TASK_ENB_APP,
  			   INSTANCE_DEFAULT, TIMER_ONE_SHOT, NULL,
  			   &x2_enb_register_retry_timer_id) < 0) {
              LOG_E(ENB_APP, " Can not start eNB X2AP register: retry timer, use \"sleep\" instead!\n");
  
              sleep(X2AP_ENB_REGISTER_RETRY_DELAY);
              /* Restart the registration process */
              x2_registered_enb = 0;
              x2_register_enb_pending = eNB_app_register_x2 (enb_id_start, enb_id_end);
            }
          }
        }
  
        break;
  
      default:
        LOG_E(ENB_APP, "Received unexpected message %s\n", ITTI_MSG_NAME (msg_p));
        break;
      }
  
      result = itti_free (ITTI_MSG_ORIGIN_ID(msg_p), msg_p);
      AssertFatal (result == EXIT_SUCCESS, "Failed to free memory (%d)!\n", result);
    } while (1);
  
  #endif
  
  
    return NULL;
  }
  
  void handle_reconfiguration(module_id_t mod_id)
  {
    struct timespec start, end;
    clock_gettime(CLOCK_MONOTONIC, &start);
    flexran_agent_info_t *flexran = RC.flexran[mod_id];
  
    LOG_I(ENB_APP, "lte-softmodem soft-restart requested\n");
  
    if (ENB_WAIT == flexran->node_ctrl_state) {
      /* this is already waiting, just release */
      pthread_mutex_lock(&flexran->mutex_node_ctrl);
      flexran->node_ctrl_state = ENB_NORMAL_OPERATION;
      pthread_mutex_unlock(&flexran->mutex_node_ctrl);
      pthread_cond_signal(&flexran->cond_node_ctrl);
      return;
    }
  
    if (stop_L1L2(mod_id) < 0) {
      LOG_E(ENB_APP, "can not stop lte-softmodem, aborting restart\n");
      return;
    }
  
    /* node_ctrl_state should have value ENB_MAKE_WAIT only if this method is not
     * executed by the FlexRAN thread */
    if (ENB_MAKE_WAIT == flexran->node_ctrl_state) {
      LOG_I(ENB_APP, " * eNB %d: Waiting for FlexRAN RTController command *\n", mod_id);
      pthread_mutex_lock(&flexran->mutex_node_ctrl);
      flexran->node_ctrl_state = ENB_WAIT;
      while (ENB_NORMAL_OPERATION != flexran->node_ctrl_state)
        pthread_cond_wait(&flexran->cond_node_ctrl, &flexran->mutex_node_ctrl);
      pthread_mutex_unlock(&flexran->mutex_node_ctrl);
    }
  
    if (restart_L1L2(mod_id) < 0) {
      LOG_E(ENB_APP, "can not restart, killing lte-softmodem\n");
      exit_fun("can not restart L1L2, killing lte-softmodem");
      return;
    }
  
    clock_gettime(CLOCK_MONOTONIC, &end);
    end.tv_sec -= start.tv_sec;
    if (end.tv_nsec >= start.tv_nsec) {
      end.tv_nsec -= start.tv_nsec;
    } else {
      end.tv_sec -= 1;
      end.tv_nsec = end.tv_nsec - start.tv_nsec + 1000000000;
    }
    LOG_I(ENB_APP, "lte-softmodem restart succeeded in %ld.%ld s\n", end.tv_sec, end.tv_nsec / 1000000);
  }
  