text: /**
   * Copyright (c) 2016 - 2018 Nordic Semiconductor ASA and Luxoft Global Operations Gmbh.
   *
   * All Rights Reserved.
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   * Redistribution and use in source and binary forms, with or without modification,
   * are permitted provided that the following conditions are met:
   *
   * 
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   *    Semiconductor ASA integrated circuit in a product or a software update for
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   *
   * 3. Neither the name of Nordic Semiconductor ASA nor the names of its
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   * 4. This software, with or without modification, must only be used with a
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  #ifndef SYS_TASK_SCHEDULER_H_INCLUDED
  #define SYS_TASK_SCHEDULER_H_INCLUDED
  
  #include <stdint.h>
  #include <stdbool.h>
  #include "sys_utils.h"
  #include "hal_atomic.h"
  #include "sys_events.h"
  
  /** @file
   * @defgroup sys_task_scheduler Task scheduler
   * @ingroup sys_15_4
   * @{
   * @brief Module for task scheduling.
   */
  
  /**@brief Identificators for registered handlers.
   *
   * Handlers will be called from the task scheduler.
   */
  typedef enum
  {
      PHY_TASK_ID,
      HAL_TASK_ID,
  #if (CONFIG_HIGHEST_LAYER_PHY == 0)
      MAC_TASK_ID,
  #endif
      APP_TASK_ID,
      SYS_TASK_ID,
      SYS_TASKS_AMOUNT
  } sys_task_ids_t;
  
  /**@brief Prototype of a task handler.
   *
   * @details Handler which will be called by the scheduler.
   */
  typedef void (* sys_task_handler_t)(void);
  
  /**@brief Pending tasks.
   *
   * @details Variable which includes markers of pending tasks.
   */
  extern volatile uint_fast16_t g_tasks;
  
  /**@brief       Notify task scheduler to add a task for execution.
   *
   * @details     The function sets a marker for the task for execution.
   *              The task handler implements a tree architecture.
   *              Task handler of each layer includes handlers of the layer's components.
   *
   * @param[in]   task_id  Task identificator.
   */
  static inline void sys_task_post(sys_task_ids_t task_id)
  {
      atomic_t atomic = 0;
  
      hal_atomic_start(&atomic);
      g_tasks |= BIT(task_id);
  #if (CONFIG_USE_SYS_TASK_NOTIFIER == 1)
      sys_event_post(SYS_EVENT_NEW_TASK, NULL);
  #endif
      hal_atomic_end(&atomic);
  }
  
  /**@brief Returns true, if there are any event flags awaiting in the system scheduler.
   */
  static inline bool sys_tasks_pending(void)
  {
      return g_tasks != 0;
  }
  
  /**@brief Handle tasks in the main function.
   *
   * @details   Handle tasks in the main function.
   */
  void sys_task_run(void);
  
  /** @} */
  
  #endif // SYS_TASK_SCHEDULER_H_INCLUDED
  