#pragma once

/*

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; either version 2 of the License, or

 *  (at your option) any later version.

 *

 *  This program is distributed in the hope that it will be useful,

 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *  GNU General Public License for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with this program; if not, write to the Free Software

 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA

 */

/** Structures and prototypes for leftmost skeleton trees (LSTs)

 *

 * @file src/lib/util/lst.h

 *

 * @copyright 2021  Network RADIUS SAS (legal@networkradius.com)

 */

RCSIDH(lst_h, "$Id: 820bdb0f6c461937d236d6fa304d698e7f37eb5b $")

#ifdef __cplusplus

extern "C" {

#endif

#include <freeradius-devel/build.h>

#include <freeradius-devel/util/misc.h>

#include <freeradius-devel/util/talloc.h>

#include <stdint.h>

typedef struct fr_lst_s fr_lst_t;

/*

 * The type of LST indexes.

 * The type passed to fr_lst_alloc() and fr_lst_talloc_alloc() in _type must be the

 * type of a structure with a member of type fr_lst_index_t. That member's name must be

 * passed as the _field argument.

 */

typedef unsigned int fr_lst_index_t;

typedef fr_lst_index_t  fr_lst_iter_t;

/** Creates an LST that can be used with non-talloced elements

 *

 * @param[in] _ctx    Talloc ctx to allocate LST in.

 * @param[in] _cmp    Comparator used to compare elements.

 * @param[in] _type   Of elements.

 * @param[in] _field    to store LST indexes in.

 * @param[in] _init   initial capacity (0 for default initial size);

 *        the capacity will be rounded up to a power of two.

 * @return

 *  - A pointer to the new LST.

 *  - NULL on error

 */

#define fr_lst_alloc(_ctx, _cmp, _type, _field, _init) \

  _fr_lst_alloc(_ctx, _cmp, NULL, (size_t)offsetof(_type, _field), _init)

/** Creates an LST that verifies elements are of a specific talloc type

 *

 * @param[in] _ctx    Talloc ctx to allocate LST in.

 * @param[in] _cmp    Comparator used to compare elements.

 * @param[in] _talloc_type  of elements.

 * @param[in] _field    to store heap indexes in.

 * @param[in] _init   initial capacity (0 for default initial size);

 *        the capacity will be rounded up to a power of two.

 * @return

 *  - A pointer to the new LST.

 *  - NULL on error.

 */

#define fr_lst_talloc_alloc(_ctx, _cmp, _talloc_type, _field, _init) \

  _fr_lst_alloc(_ctx, _cmp, #_talloc_type, (size_t)offsetof(_talloc_type, _field), _init)

fr_lst_t *_fr_lst_alloc(TALLOC_CTX *ctx, fr_cmp_t cmp, char const *type, size_t offset, fr_lst_index_t init) CC_HINT(nonnull(2));

/** Check if an entry is inserted into an LST.

 *

 * @param[in] lst_id    An fr_lst_index_t value *as stored in an item*

 *

 * Thus one should only pass this function an index as retrieved directly from

 * the item, *not* the value returned by item_index() (q.v.).

 *

 * This checks a necessary condition for a fr_lst_index_t value to be

 * that of an inserted entry. A more complete check would need the entry

 * itself and a pointer to the fr_lst_t it may be inserted in.

 * Provided here to let heap users move to LSTs.

 */

static inline bool fr_lst_entry_inserted(fr_lst_index_t lst_id)

{

  return (lst_id > 0);

}

Unexecuted instantiation: timer.c:fr_lst_entry_inserted

Unexecuted instantiation: lst.c:fr_lst_entry_inserted

void  *fr_lst_peek(fr_lst_t *lst) CC_HINT(nonnull);

void  *fr_lst_pop(fr_lst_t *lst) CC_HINT(nonnull);

int   fr_lst_insert(fr_lst_t *lst, void *data) CC_HINT(nonnull);

int fr_lst_extract(fr_lst_t *lst, void *data) CC_HINT(nonnull);

unsigned int  fr_lst_num_elements(fr_lst_t *lst) CC_HINT(nonnull);

void    *fr_lst_iter_init(fr_lst_t *lst, fr_lst_iter_t *iter) CC_HINT(nonnull);

void    *fr_lst_iter_next(fr_lst_t *lst, fr_lst_iter_t *iter) CC_HINT(nonnull);

#ifndef TALLOC_GET_TYPE_ABORT_NOOP

void fr_lst_verify(char const *file, int line, fr_lst_t const *lst);

#define FR_LST_VERIFY(_lst) fr_lst_verify(__FILE__, __LINE__, _lst)

#elif !defined(NDEBUG)

#define FR_LST_VERIFY(_lst) fr_assert(_lst)

#else

#define FR_LST_VERIFY(_lst)

#endif

/** Iterate over the contents of an LST

 *

 * @note The initializer section of a for loop can't declare variables with distinct

 *   base types, so we require a containing block, and can't follow the standard

 *   do {...} while(0) dodge. The code to be run for each item in the LST should

 *   thus start with one open brace and end with two close braces, and shouldn't

 *   be followed with a semicolon.

 *   This may fake out code formatting programs and code-aware editors.

 *

 * @param[in] _lst    to iterate over.

 * @param[in] _type   of item the heap contains.

 * @param[in] _data   Name of variable holding a pointer to the LST element.

 *        Will be declared in the scope of the loop.

 */

#define fr_lst_foreach(_lst, _type, _data) \

{ \

  fr_lst_iter_t _iter; \

  for (_type *_data = fr_lst_iter_init(_lst, &_iter); _data; _data = fr_lst_iter_next(_lst, &_iter))

#ifdef __cplusplus

}

#endif