source: arduino-1-6-7/trunk/fuentes/arduino-ide-amd64/hardware/tools/avr/lib/gcc/avr/4.8.1/plugin/include/hashtab.h @ 46

Last change on this file since 46 was 46, checked in by jrpelegrina, 4 years ago

First release to Xenial

File size: 7.2 KB
Line 
1/* An expandable hash tables datatype. 
2   Copyright (C) 1999, 2000, 2002, 2003, 2004, 2005, 2009, 2010
3   Free Software Foundation, Inc.
4   Contributed by Vladimir Makarov (vmakarov@cygnus.com).
5
6This program is free software; you can redistribute it and/or modify
7it under the terms of the GNU General Public License as published by
8the Free Software Foundation; either version 2 of the License, or
9(at your option) any later version.
10
11This program is distributed in the hope that it will be useful,
12but WITHOUT ANY WARRANTY; without even the implied warranty of
13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14GNU General Public License for more details.
15
16You should have received a copy of the GNU General Public License
17along with this program; if not, write to the Free Software
18Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
19
20/* This package implements basic hash table functionality.  It is possible
21   to search for an entry, create an entry and destroy an entry.
22
23   Elements in the table are generic pointers.
24
25   The size of the table is not fixed; if the occupancy of the table
26   grows too high the hash table will be expanded.
27
28   The abstract data implementation is based on generalized Algorithm D
29   from Knuth's book "The art of computer programming".  Hash table is
30   expanded by creation of new hash table and transferring elements from
31   the old table to the new table.  */
32
33#ifndef __HASHTAB_H__
34#define __HASHTAB_H__
35
36#ifdef __cplusplus
37extern "C" {
38#endif /* __cplusplus */
39
40#include "ansidecl.h"
41
42#ifndef GTY
43#define GTY(X)
44#endif
45
46/* The type for a hash code.  */
47typedef unsigned int hashval_t;
48
49/* Callback function pointer types.  */
50
51/* Calculate hash of a table entry.  */
52typedef hashval_t (*htab_hash) (const void *);
53
54/* Compare a table entry with a possible entry.  The entry already in
55   the table always comes first, so the second element can be of a
56   different type (but in this case htab_find and htab_find_slot
57   cannot be used; instead the variants that accept a hash value
58   must be used).  */
59typedef int (*htab_eq) (const void *, const void *);
60
61/* Cleanup function called whenever a live element is removed from
62   the hash table.  */
63typedef void (*htab_del) (void *);
64 
65/* Function called by htab_traverse for each live element.  The first
66   arg is the slot of the element (which can be passed to htab_clear_slot
67   if desired), the second arg is the auxiliary pointer handed to
68   htab_traverse.  Return 1 to continue scan, 0 to stop.  */
69typedef int (*htab_trav) (void **, void *);
70
71/* Memory-allocation function, with the same functionality as calloc().
72   Iff it returns NULL, the hash table implementation will pass an error
73   code back to the user, so if your code doesn't handle errors,
74   best if you use xcalloc instead.  */
75typedef void *(*htab_alloc) (size_t, size_t);
76
77/* We also need a free() routine.  */
78typedef void (*htab_free) (void *);
79
80/* Memory allocation and deallocation; variants which take an extra
81   argument.  */
82typedef void *(*htab_alloc_with_arg) (void *, size_t, size_t);
83typedef void (*htab_free_with_arg) (void *, void *);
84
85/* This macro defines reserved value for empty table entry.  */
86
87#define HTAB_EMPTY_ENTRY    ((PTR) 0)
88
89/* This macro defines reserved value for table entry which contained
90   a deleted element. */
91
92#define HTAB_DELETED_ENTRY  ((PTR) 1)
93
94/* Hash tables are of the following type.  The structure
95   (implementation) of this type is not needed for using the hash
96   tables.  All work with hash table should be executed only through
97   functions mentioned below.  The size of this structure is subject to
98   change.  */
99
100struct GTY(()) htab {
101  /* Pointer to hash function.  */
102  htab_hash hash_f;
103
104  /* Pointer to comparison function.  */
105  htab_eq eq_f;
106
107  /* Pointer to cleanup function.  */
108  htab_del del_f;
109
110  /* Table itself.  */
111  void ** GTY ((use_param, length ("%h.size"))) entries;
112
113  /* Current size (in entries) of the hash table.  */
114  size_t size;
115
116  /* Current number of elements including also deleted elements.  */
117  size_t n_elements;
118
119  /* Current number of deleted elements in the table.  */
120  size_t n_deleted;
121
122  /* The following member is used for debugging. Its value is number
123     of all calls of `htab_find_slot' for the hash table. */
124  unsigned int searches;
125
126  /* The following member is used for debugging.  Its value is number
127     of collisions fixed for time of work with the hash table. */
128  unsigned int collisions;
129
130  /* Pointers to allocate/free functions.  */
131  htab_alloc alloc_f;
132  htab_free free_f;
133
134  /* Alternate allocate/free functions, which take an extra argument.  */
135  void * GTY((skip)) alloc_arg;
136  htab_alloc_with_arg alloc_with_arg_f;
137  htab_free_with_arg free_with_arg_f;
138
139  /* Current size (in entries) of the hash table, as an index into the
140     table of primes.  */
141  unsigned int size_prime_index;
142};
143
144typedef struct htab *htab_t;
145
146/* An enum saying whether we insert into the hash table or not.  */
147enum insert_option {NO_INSERT, INSERT};
148
149/* The prototypes of the package functions. */
150
151extern htab_t   htab_create_alloc  (size_t, htab_hash,
152                                    htab_eq, htab_del,
153                                    htab_alloc, htab_free);
154
155extern htab_t   htab_create_alloc_ex (size_t, htab_hash,
156                                      htab_eq, htab_del,
157                                      void *, htab_alloc_with_arg,
158                                      htab_free_with_arg);
159
160extern htab_t  htab_create_typed_alloc (size_t, htab_hash, htab_eq, htab_del,
161                                        htab_alloc, htab_alloc, htab_free);
162
163/* Backward-compatibility functions.  */
164extern htab_t htab_create (size_t, htab_hash, htab_eq, htab_del);
165extern htab_t htab_try_create (size_t, htab_hash, htab_eq, htab_del);
166
167extern void     htab_set_functions_ex (htab_t, htab_hash,
168                                       htab_eq, htab_del,
169                                       void *, htab_alloc_with_arg,
170                                       htab_free_with_arg);
171
172extern void     htab_delete (htab_t);
173extern void     htab_empty (htab_t);
174
175extern void *   htab_find (htab_t, const void *);
176extern void **  htab_find_slot (htab_t, const void *, enum insert_option);
177extern void *   htab_find_with_hash (htab_t, const void *, hashval_t);
178extern void **  htab_find_slot_with_hash (htab_t, const void *,
179                                          hashval_t, enum insert_option);
180extern void     htab_clear_slot (htab_t, void **);
181extern void     htab_remove_elt (htab_t, void *);
182extern void     htab_remove_elt_with_hash (htab_t, void *, hashval_t);
183
184extern void     htab_traverse (htab_t, htab_trav, void *);
185extern void     htab_traverse_noresize (htab_t, htab_trav, void *);
186
187extern size_t   htab_size (htab_t);
188extern size_t   htab_elements (htab_t);
189extern double   htab_collisions (htab_t);
190
191/* A hash function for pointers.  */
192extern htab_hash htab_hash_pointer;
193
194/* An equality function for pointers.  */
195extern htab_eq htab_eq_pointer;
196
197/* A hash function for null-terminated strings.  */
198extern hashval_t htab_hash_string (const void *);
199
200/* An iterative hash function for arbitrary data.  */
201extern hashval_t iterative_hash (const void *, size_t, hashval_t);
202/* Shorthand for hashing something with an intrinsic size.  */
203#define iterative_hash_object(OB,INIT) iterative_hash (&OB, sizeof (OB), INIT)
204
205#ifdef __cplusplus
206}
207#endif /* __cplusplus */
208
209#endif /* __HASHTAB_H */
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