git/iterator.h

#ifndef ITERATOR_H
#define ITERATOR_H

/*
 * Generic constants related to iterators.
 */

/*
 * The attempt to advance the iterator was successful; the iterator
 * reflects the new current entry.
 */
#define ITER_OK …

/*
 * The iterator is exhausted and has been freed.
 */
#define ITER_DONE …

/*
 * The iterator experienced an error. The iteration has been aborted
 * and the iterator has been freed.
 */
#define ITER_ERROR …

/*
 * Return values for selector functions for merge iterators. The
 * numerical values of these constants are important and must be
 * compatible with ITER_DONE and ITER_ERROR.
 */
enum iterator_selection { … };

#endif /* ITERATOR_H */