1/* A splay-tree datatype.
2   Copyright 1998, 1999, 2000, 2002, 2005, 2007, 2009, 2010
3   Free Software Foundation, Inc.
4   Contributed by Mark Mitchell (mark@markmitchell.com).
5
6   This file is part of GCC.
7
8   GCC is free software; you can redistribute it and/or modify it
9   under the terms of the GNU General Public License as published by
10   the Free Software Foundation; either version 2, or (at your option)
11   any later version.
12
13   GCC is distributed in the hope that it will be useful, but
14   WITHOUT ANY WARRANTY; without even the implied warranty of
15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16   General Public License for more details.
17
18   You should have received a copy of the GNU General Public License
19   along with GCC; see the file COPYING.  If not, write to
20   the Free Software Foundation, 51 Franklin Street - Fifth Floor,
21   Boston, MA 02110-1301, USA.  */
22
23/* For an easily readable description of splay-trees, see:
24
25     Lewis, Harry R. and Denenberg, Larry.  Data Structures and Their
26     Algorithms.  Harper-Collins, Inc.  1991.
27
28   The major feature of splay trees is that all basic tree operations
29   are amortized O(log n) time for a tree with n nodes.  */
30
31#ifndef _SPLAY_TREE_H
32#define _SPLAY_TREE_H
33
34#ifdef __cplusplus
35extern "C" {
36#endif /* __cplusplus */
37
38#include "ansidecl.h"
39
40#ifdef HAVE_STDINT_H
41#include <stdint.h>
42#endif
43#ifdef HAVE_INTTYPES_H
44#include <inttypes.h>
45#endif
46
47/* Use typedefs for the key and data types to facilitate changing
48   these types, if necessary.  These types should be sufficiently wide
49   that any pointer or scalar can be cast to these types, and then
50   cast back, without loss of precision.  */
51typedef uintptr_t splay_tree_key;
52typedef uintptr_t splay_tree_value;
53
54/* Forward declaration for a node in the tree.  */
55typedef struct splay_tree_node_s *splay_tree_node;
56
57/* The type of a function which compares two splay-tree keys.  The
58   function should return values as for qsort.  */
59typedef int (*splay_tree_compare_fn) (splay_tree_key, splay_tree_key);
60
61/* The type of a function used to deallocate any resources associated
62   with the key.  */
63typedef void (*splay_tree_delete_key_fn) (splay_tree_key);
64
65/* The type of a function used to deallocate any resources associated
66   with the value.  */
67typedef void (*splay_tree_delete_value_fn) (splay_tree_value);
68
69/* The type of a function used to iterate over the tree.  */
70typedef int (*splay_tree_foreach_fn) (splay_tree_node, void*);
71
72/* The type of a function used to allocate memory for tree root and
73   node structures.  The first argument is the number of bytes needed;
74   the second is a data pointer the splay tree functions pass through
75   to the allocator.  This function must never return zero.  */
76typedef void *(*splay_tree_allocate_fn) (int, void *);
77
78/* The type of a function used to free memory allocated using the
79   corresponding splay_tree_allocate_fn.  The first argument is the
80   memory to be freed; the latter is a data pointer the splay tree
81   functions pass through to the freer.  */
82typedef void (*splay_tree_deallocate_fn) (void *, void *);
83
84/* The nodes in the splay tree.  */
85struct splay_tree_node_s {
86  /* The key.  */
87  splay_tree_key key;
88
89  /* The value.  */
90  splay_tree_value value;
91
92  /* The left and right children, respectively.  */
93  splay_tree_node left;
94  splay_tree_node right;
95};
96
97/* The splay tree itself.  */
98struct splay_tree_s {
99  /* The root of the tree.  */
100  splay_tree_node root;
101
102  /* The comparision function.  */
103  splay_tree_compare_fn comp;
104
105  /* The deallocate-key function.  NULL if no cleanup is necessary.  */
106  splay_tree_delete_key_fn delete_key;
107
108  /* The deallocate-value function.  NULL if no cleanup is necessary.  */
109  splay_tree_delete_value_fn delete_value;
110
111  /* Node allocate function.  Takes allocate_data as a parameter. */
112  splay_tree_allocate_fn allocate;
113
114  /* Free function for nodes and trees.  Takes allocate_data as a parameter.  */
115  splay_tree_deallocate_fn deallocate;
116
117  /* Parameter for allocate/free functions.  */
118  void *allocate_data;
119};
120
121typedef struct splay_tree_s *splay_tree;
122
123extern splay_tree splay_tree_new (splay_tree_compare_fn,
124				  splay_tree_delete_key_fn,
125				  splay_tree_delete_value_fn);
126extern splay_tree splay_tree_new_with_allocator (splay_tree_compare_fn,
127						 splay_tree_delete_key_fn,
128						 splay_tree_delete_value_fn,
129						 splay_tree_allocate_fn,
130						 splay_tree_deallocate_fn,
131						 void *);
132extern splay_tree splay_tree_new_typed_alloc (splay_tree_compare_fn,
133					      splay_tree_delete_key_fn,
134					      splay_tree_delete_value_fn,
135					      splay_tree_allocate_fn,
136					      splay_tree_allocate_fn,
137					      splay_tree_deallocate_fn,
138					      void *);
139extern void splay_tree_delete (splay_tree);
140extern splay_tree_node splay_tree_insert (splay_tree,
141					  splay_tree_key,
142					  splay_tree_value);
143extern void splay_tree_remove	(splay_tree, splay_tree_key);
144extern splay_tree_node splay_tree_lookup (splay_tree, splay_tree_key);
145extern splay_tree_node splay_tree_predecessor (splay_tree, splay_tree_key);
146extern splay_tree_node splay_tree_successor (splay_tree, splay_tree_key);
147extern splay_tree_node splay_tree_max (splay_tree);
148extern splay_tree_node splay_tree_min (splay_tree);
149extern int splay_tree_foreach (splay_tree, splay_tree_foreach_fn, void*);
150extern int splay_tree_compare_ints (splay_tree_key, splay_tree_key);
151extern int splay_tree_compare_pointers (splay_tree_key,	splay_tree_key);
152
153#ifdef __cplusplus
154}
155#endif /* __cplusplus */
156
157#endif /* _SPLAY_TREE_H */
158