ChibiOS Free Embedded RTOS

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  /*------------------------------------------------------------------------*
   * chibios_rt::ObjectsPool                                                *
   *------------------------------------------------------------------------*/
  /**
   * @brief   Template class encapsulating a memory pool and its elements.
   */
  template<class T, size_t N>
  class ObjectsPool : public MemoryPool {
  private:
    /* The buffer is declared as an array of pointers to void for two
       reasons:
       1) The objects must be properly aligned to hold a pointer as
          first field.
       2) There is no need to invoke constructors for object that are
          into the pool.*/
    void *pool_buf[(N * sizeof (T)) / sizeof (void *)];

  public:
    /**
     * @brief   ObjectsPool constructor.
     *
     * @init
     */
    ObjectsPool(void) : MemoryPool(sizeof (T), NULL) {

      loadArray(pool_buf, N);
    }
  };

Code: Select all

  /*------------------------------------------------------------------------*
   * chibios_rt::ObjectsPool                                                *
   *------------------------------------------------------------------------*/
  /**
   * @brief   Template class encapsulating a memory pool and its elements.
   */
  template<class T, size_t N>
  class ObjectsPool : protected MemoryPool {
  private:
    /* The buffer is declared as an array of pointers to void for two
       reasons:
       1) The objects must be properly aligned to hold a pointer as
          first field.
       2) There is no need to invoke constructors for object that are
          in the pool.*/
    void *pool_buf[(N * sizeof (T)) / sizeof (void *)];

  public:
    /**
     * @brief   ObjectsPool constructor.
     *
     * @init
     */
    ObjectsPool(void) : MemoryPool(sizeof (T), NULL) {
      loadArray(pool_buf, N);
    }

    T *alloc(void) {
      const void *p = MemoryPool::alloc();

      // §5.3.4/13:
      // If the allocation function returns null, initialization shall not be
      // done, the deallocation function shall not be called, and the value of
      // the new-expression shall be null.
      //
      // So we might be able to skip this check...
      if (!p)
        return 0;

      return new(p) T();
    }
    
    void free(T *objp) {
      objp->~T();
      MemoryPool::free(objp);
    }

  };