libgomp/splay-tree.h

/* A splay-tree datatype.
   Copyright (C) 1998-2025 Free Software Foundation, Inc.
   Contributed by Mark Mitchell (mark@markmitchell.com).

   This file is part of the GNU Offloading and Multi Processing Library
   (libgomp).

   Libgomp 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 3, or (at your option)
   any later version.

   Libgomp 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.

   Under Section 7 of GPL version 3, you are granted additional
   permissions described in the GCC Runtime Library Exception, version
   3.1, as published by the Free Software Foundation.

   You should have received a copy of the GNU General Public License and
   a copy of the GCC Runtime Library Exception along with this program;
   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
   <http://www.gnu.org/licenses/>.  */

/* The splay tree code copied from include/splay-tree.h and adjusted,
   so that all the data lives directly in splay_tree_node_s structure
   and no extra allocations are needed.

   Files including this header should before including it add:
typedef struct splay_tree_node_s *splay_tree_node;
typedef struct splay_tree_s *splay_tree;
typedef struct splay_tree_key_s *splay_tree_key;
   define splay_tree_key_s structure, and define
   splay_compare inline function.

   Define splay_tree_static to mark all functions as static.

   Alternatively, they can define splay_tree_prefix macro before
   including this header and then all the above types, the
   splay_compare function and the splay_tree_{lookup,insert_remove}
   function will be prefixed by that prefix.  If splay_tree_prefix
   macro is defined, this header must be included twice: once where
   you need the header file definitions, and once where you need the
   .c implementation routines.  In the latter case, you must also
   define the macro splay_tree_c.  See the include of splay-tree.h in
   priority_queue.[hc] for an example.  */

/* For an easily readable description of splay-trees, see:

     Lewis, Harry R. and Denenberg, Larry.  Data Structures and Their
     Algorithms.  Harper-Collins, Inc.  1991.

   The major feature of splay trees is that all basic tree operations
   are amortized O(log n) time for a tree with n nodes.  */

#ifdef splay_tree_prefix
# define splay_tree_name_1(prefix, name) prefix ## _ ## name
# define splay_tree_name(prefix, name) splay_tree_name_1 (prefix, name)
# define splay_tree_node_s	\
    splay_tree_name (splay_tree_prefix, splay_tree_node_s)
# define splay_tree_s		\
    splay_tree_name (splay_tree_prefix, splay_tree_s)
# define splay_tree_key_s	\
    splay_tree_name (splay_tree_prefix, splay_tree_key_s)
# define splay_tree_node	\
    splay_tree_name (splay_tree_prefix, splay_tree_node)
# define splay_tree		\
    splay_tree_name (splay_tree_prefix, splay_tree)
# define splay_tree_key		\
    splay_tree_name (splay_tree_prefix, splay_tree_key)
# define splay_compare		\
    splay_tree_name (splay_tree_prefix, splay_compare)
# define splay_tree_lookup	\
    splay_tree_name (splay_tree_prefix, splay_tree_lookup)
# define splay_tree_lookup_node	\
    splay_tree_name (splay_tree_prefix, splay_tree_lookup_node)
# define splay_tree_insert	\
    splay_tree_name (splay_tree_prefix, splay_tree_insert)
# define splay_tree_remove	\
    splay_tree_name (splay_tree_prefix, splay_tree_remove)
# define splay_tree_foreach	\
    splay_tree_name (splay_tree_prefix, splay_tree_foreach)
# define splay_tree_foreach_lazy \
    splay_tree_name (splay_tree_prefix, splay_tree_foreach_lazy)
# define splay_tree_callback	\
    splay_tree_name (splay_tree_prefix, splay_tree_callback)
# define splay_tree_callback_stop	\
    splay_tree_name (splay_tree_prefix, splay_tree_callback_stop)
#endif

#ifndef splay_tree_c
/* Header file definitions and prototypes.  */

/* The nodes in the splay tree.  */
struct splay_tree_node_s {
  struct splay_tree_key_s key;
  /* The left and right children, respectively.  */
  splay_tree_node left;
  splay_tree_node right;
};

/* The splay tree.  */
struct splay_tree_s {
  splay_tree_node root;
};

typedef void (*splay_tree_callback) (splay_tree_key, void *);
typedef int (*splay_tree_callback_stop) (splay_tree_key, void *);

#ifndef splay_tree_static
extern splay_tree_key splay_tree_lookup (splay_tree, splay_tree_key);
extern splay_tree_node splay_tree_lookup_node (splay_tree, splay_tree_key);
extern void splay_tree_insert (splay_tree, splay_tree_node);
extern void splay_tree_remove (splay_tree, splay_tree_key);
extern void splay_tree_foreach (splay_tree, splay_tree_callback, void *);
extern void splay_tree_foreach_lazy (splay_tree, splay_tree_callback_stop, void *);
#endif

#ifdef splay_tree_static_unused_attr
#  undef splay_tree_static_unused_attr
#endif

#else  /* splay_tree_c */
#  ifdef splay_tree_prefix
#    include "splay-tree.c"
#  endif
#  undef splay_tree_c
#endif /* #ifndef splay_tree_c */

#ifdef splay_tree_static
#  undef splay_tree_static
#endif

#ifdef splay_tree_prefix
#  undef splay_tree_name_1
#  undef splay_tree_name
#  undef splay_tree_node_s
#  undef splay_tree_s
#  undef splay_tree_key_s
#  undef splay_tree_node
#  undef splay_tree
#  undef splay_tree_key
#  undef splay_compare
#  undef splay_tree_lookup
#  undef splay_tree_lookup_node
#  undef splay_tree_insert
#  undef splay_tree_remove
#  undef splay_tree_foreach
#  undef splay_tree_foreach_lazy
#  undef splay_tree_callback
#  undef splay_tree_callback_stop
#  undef splay_tree_prefix
#endif