include/splay-tree.h

   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
  35 extern "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.  */
  51 typedef uintptr_t splay_tree_key;
  52 typedef uintptr_t splay_tree_value;
  53
  54 /* Forward declaration for a node in the tree.  */
  55 typedef 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.  */
  59 typedef 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.  */
  63 typedef 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.  */
  67 typedef void (*splay_tree_delete_value_fn) (splay_tree_value);
  68
  69 /* The type of a function used to iterate over the tree.  */
  70 typedef 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.  */
  76 typedef 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.  */
  82 typedef void (*splay_tree_deallocate_fn) (void *, void *);
  83
  84 /* The nodes in the splay tree.  */
  85 struct 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.  */
  98 struct 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
 121 typedef struct splay_tree_s *splay_tree;
 122
 123 extern splay_tree splay_tree_new (splay_tree_compare_fn,
 124                                   splay_tree_delete_key_fn,
 125                                   splay_tree_delete_value_fn);
 126 extern 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 *);
 132 extern 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 *);
 139 extern void splay_tree_delete (splay_tree);
 140 extern splay_tree_node splay_tree_insert (splay_tree,
 141                                           splay_tree_key,
 142                                           splay_tree_value);
 143 extern void splay_tree_remove   (splay_tree, splay_tree_key);
 144 extern splay_tree_node splay_tree_lookup (splay_tree, splay_tree_key);
 145 extern splay_tree_node splay_tree_predecessor (splay_tree, splay_tree_key);
 146 extern splay_tree_node splay_tree_successor (splay_tree, splay_tree_key);
 147 extern splay_tree_node splay_tree_max (splay_tree);
 148 extern splay_tree_node splay_tree_min (splay_tree);
 149 extern int splay_tree_foreach (splay_tree, splay_tree_foreach_fn, void*);
 150 extern int splay_tree_compare_ints (splay_tree_key, splay_tree_key);
 151 extern 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 */