1  /*
       2   * Copyright (C) 2009-2014 Karel Zak <kzak@redhat.com>
       3   * Copyright (C) 2014 Ondrej Oprala <ooprala@redhat.com>
       4   *
       5   * This file may be redistributed under the terms of the
       6   * GNU Lesser General Public License.
       7   */
       8  
       9  /**
      10   * SECTION: iter
      11   * @title: Iterator
      12   * @short_description: unified iterator
      13   *
      14   * The iterator keeps the direction and the last position
      15   * for access to the internal library tables/lists.
      16   */
      17  
      18  #include <string.h>
      19  #include <stdlib.h>
      20  
      21  #include "smartcolsP.h"
      22  
      23  /**
      24   * scols_new_iter:
      25   * @direction: SCOLS_INTER_{FOR,BACK}WARD direction
      26   *
      27   * Returns: newly allocated generic libmount iterator.
      28   */
      29  struct libscols_iter *scols_new_iter(int direction)
      30  {
      31  	struct libscols_iter *itr = calloc(1, sizeof(*itr));
      32  	if (!itr)
      33  		return NULL;
      34  	itr->direction = direction;
      35  	return itr;
      36  }
      37  
      38  /**
      39   * scols_free_iter:
      40   * @itr: iterator pointer
      41   *
      42   * Deallocates the iterator.
      43   */
      44  void scols_free_iter(struct libscols_iter *itr)
      45  {
      46  	free(itr);
      47  }
      48  
      49  /**
      50   * scols_reset_iter:
      51   * @itr: iterator pointer
      52   * @direction: SCOLS_INTER_{FOR,BACK}WARD or -1 to keep the direction unchanged
      53   *
      54   * Resets the iterator.
      55   */
      56  void scols_reset_iter(struct libscols_iter *itr, int direction)
      57  {
      58  	if (direction == -1)
      59  		direction = itr->direction;
      60  
      61  	memset(itr, 0, sizeof(*itr));
      62  	itr->direction = direction;
      63  }
      64  
      65  /**
      66   * scols_iter_get_direction:
      67   * @itr: iterator pointer
      68   *
      69   * Returns: SCOLS_INTER_{FOR,BACK}WARD
      70   */
      71  int scols_iter_get_direction(const struct libscols_iter *itr)
      72  {
      73  	return itr->direction;
      74  }