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 #ifndef GTY
  48 #define GTY(X)
  49 #endif
  50
  51 /* Use typedefs for the key and data types to facilitate changing
  52    these types, if necessary.  These types should be sufficiently wide
  53    that any pointer or scalar can be cast to these types, and then
  54    cast back, without loss of precision.  */
  55 typedef uintptr_t splay_tree_key;
  56 typedef uintptr_t splay_tree_value;
  57
  58 /* Forward declaration for a node in the tree.  */
  59 typedef struct splay_tree_node_s *splay_tree_node;
  60
  61 /* The type of a function which compares two splay-tree keys.  The
  62    function should return values as for qsort.  */
  63 typedef int (*splay_tree_compare_fn) (splay_tree_key, splay_tree_key);
  64
  65 /* The type of a function used to deallocate any resources associated
  66    with the key.  */
  67 typedef void (*splay_tree_delete_key_fn) (splay_tree_key);
  68
  69 /* The type of a function used to deallocate any resources associated
  70    with the value.  */
  71 typedef void (*splay_tree_delete_value_fn) (splay_tree_value);
  72
  73 /* The type of a function used to iterate over the tree.  */
  74 typedef int (*splay_tree_foreach_fn) (splay_tree_node, void*);
  75
  76 /* The type of a function used to allocate memory for tree root and
  77    node structures.  The first argument is the number of bytes needed;
  78    the second is a data pointer the splay tree functions pass through
  79    to the allocator.  This function must never return zero.  */
  80 typedef void *(*splay_tree_allocate_fn) (int, void *);
  81
  82 /* The type of a function used to free memory allocated using the
  83    corresponding splay_tree_allocate_fn.  The first argument is the
  84    memory to be freed; the latter is a data pointer the splay tree
  85    functions pass through to the freer.  */
  86 typedef void (*splay_tree_deallocate_fn) (void *, void *);
  87
  88 /* The nodes in the splay tree.  */
  89 struct GTY(()) splay_tree_node_s {
  90   /* The key.  */
  91   splay_tree_key GTY ((use_param1)) key;
  92
  93   /* The value.  */
  94   splay_tree_value GTY ((use_param2)) value;
  95
  96   /* The left and right children, respectively.  */
  97   splay_tree_node GTY ((use_params)) left;
  98   splay_tree_node GTY ((use_params)) right;
  99 };
 100
 101 /* The splay tree itself.  */
 102 struct GTY(()) splay_tree_s {
 103   /* The root of the tree.  */
 104   splay_tree_node GTY ((use_params)) root;
 105
 106   /* The comparision function.  */
 107   splay_tree_compare_fn comp;
 108
 109   /* The deallocate-key function.  NULL if no cleanup is necessary.  */
 110   splay_tree_delete_key_fn delete_key;
 111
 112   /* The deallocate-value function.  NULL if no cleanup is necessary.  */
 113   splay_tree_delete_value_fn delete_value;
 114
 115   /* Node allocate function.  Takes allocate_data as a parameter. */
 116   splay_tree_allocate_fn allocate;
 117
 118   /* Free function for nodes and trees.  Takes allocate_data as a parameter.  */
 119   splay_tree_deallocate_fn deallocate;
 120
 121   /* Parameter for allocate/free functions.  */
 122   void * GTY((skip)) allocate_data;
 123 };
 124
 125 typedef struct splay_tree_s *splay_tree;
 126
 127 extern splay_tree splay_tree_new (splay_tree_compare_fn,
 128                                   splay_tree_delete_key_fn,
 129                                   splay_tree_delete_value_fn);
 130 extern splay_tree splay_tree_new_with_allocator (splay_tree_compare_fn,
 131                                                  splay_tree_delete_key_fn,
 132                                                  splay_tree_delete_value_fn,
 133                                                  splay_tree_allocate_fn,
 134                                                  splay_tree_deallocate_fn,
 135                                                  void *);
 136 extern splay_tree splay_tree_new_typed_alloc (splay_tree_compare_fn,
 137                                               splay_tree_delete_key_fn,
 138                                               splay_tree_delete_value_fn,
 139                                               splay_tree_allocate_fn,
 140                                               splay_tree_allocate_fn,
 141                                               splay_tree_deallocate_fn,
 142                                               void *);
 143 extern void splay_tree_delete (splay_tree);
 144 extern splay_tree_node splay_tree_insert (splay_tree,
 145                                           splay_tree_key,
 146                                           splay_tree_value);
 147 extern void splay_tree_remove   (splay_tree, splay_tree_key);
 148 extern splay_tree_node splay_tree_lookup (splay_tree, splay_tree_key);
 149 extern splay_tree_node splay_tree_predecessor (splay_tree, splay_tree_key);
 150 extern splay_tree_node splay_tree_successor (splay_tree, splay_tree_key);
 151 extern splay_tree_node splay_tree_max (splay_tree);
 152 extern splay_tree_node splay_tree_min (splay_tree);
 153 extern int splay_tree_foreach (splay_tree, splay_tree_foreach_fn, void*);
 154 extern int splay_tree_compare_ints (splay_tree_key, splay_tree_key);
 155 extern int splay_tree_compare_pointers (splay_tree_key, splay_tree_key);
 156
 157 #ifdef __cplusplus
 158 }
 159 #endif /* __cplusplus */
 160
 161 #endif /* _SPLAY_TREE_H */