typedef struct extent_hooks_s extent_hooks_t;

/*
 * void *
 * extent_alloc(extent_hooks_t *extent_hooks, void *new_addr, size_t size,
 *     size_t alignment, bool *zero, bool *commit, unsigned arena_ind);
 */
typedef void *(extent_alloc_t)(extent_hooks_t *, void *, size_t, size_t, bool *,
    bool *, unsigned);

/*
 * bool
 * extent_dalloc(extent_hooks_t *extent_hooks, void *addr, size_t size,
 *     bool committed, unsigned arena_ind);
 */
typedef bool (extent_dalloc_t)(extent_hooks_t *, void *, size_t, bool,
    unsigned);

/*
 * void
 * extent_destroy(extent_hooks_t *extent_hooks, void *addr, size_t size,
 *     bool committed, unsigned arena_ind);
 */
typedef void (extent_destroy_t)(extent_hooks_t *, void *, size_t, bool,
    unsigned);

/*
 * bool
 * extent_commit(extent_hooks_t *extent_hooks, void *addr, size_t size,
 *     size_t offset, size_t length, unsigned arena_ind);
 */
typedef bool (extent_commit_t)(extent_hooks_t *, void *, size_t, size_t, size_t,
    unsigned);

/*
 * bool
 * extent_decommit(extent_hooks_t *extent_hooks, void *addr, size_t size,
 *     size_t offset, size_t length, unsigned arena_ind);
 */
typedef bool (extent_decommit_t)(extent_hooks_t *, void *, size_t, size_t,
    size_t, unsigned);

/*
 * bool
 * extent_purge(extent_hooks_t *extent_hooks, void *addr, size_t size,
 *     size_t offset, size_t length, unsigned arena_ind);
 */
typedef bool (extent_purge_t)(extent_hooks_t *, void *, size_t, size_t, size_t,
    unsigned);

/*
 * bool
 * extent_split(extent_hooks_t *extent_hooks, void *addr, size_t size,
 *     size_t size_a, size_t size_b, bool committed, unsigned arena_ind);
 */
typedef bool (extent_split_t)(extent_hooks_t *, void *, size_t, size_t, size_t,
    bool, unsigned);

/*
 * bool
 * extent_merge(extent_hooks_t *extent_hooks, void *addr_a, size_t size_a,
 *     void *addr_b, size_t size_b, bool committed, unsigned arena_ind);
 */
typedef bool (extent_merge_t)(extent_hooks_t *, void *, size_t, void *, size_t,
    bool, unsigned);

struct extent_hooks_s {
        extent_alloc_t          *alloc;
        extent_dalloc_t         *dalloc;
        extent_destroy_t        *destroy;
        extent_commit_t         *commit;
        extent_decommit_t       *decommit;
        extent_purge_t          *purge_lazy;
        extent_purge_t          *purge_forced;
        extent_split_t          *split;
        extent_merge_t          *merge;
};