1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
3 * Copyright (C) 1999 The Free Software Foundation
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Library General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Library General Public License for more details.
15 * You should have received a copy of the GNU Library General Public
16 * License along with this library; if not, write to the
17 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 * Boston, MA 02111-1307, USA.
22 * Modified by the GLib Team and others 1997-1999. See the AUTHORS
23 * file for a list of people on the GLib Team. See the ChangeLog
24 * files for a list of changes. These files are distributed with
25 * GLib at ftp://ftp.gtk.org/pub/gtk/.
49 my_hash_callback_remove (gpointer key
,
62 my_hash_callback_remove_test (gpointer key
,
69 g_assert_not_reached ();
73 my_hash_callback (gpointer key
,
82 my_hash (gconstpointer key
)
84 return (guint
) *((const gint
*) key
);
88 my_hash_compare (gconstpointer a
,
91 return *((const gint
*) a
) == *((const gint
*) b
);
97 * This is a simplified version of the pathalias hashing function.
98 * Thanks to Steve Belovin and Peter Honeyman
100 * hash a string into a long int. 31 bit crc (from andrew appel).
101 * the crc table is computed at run time by crcinit() -- we could
102 * precompute, but it takes 1 clock tick on a 750.
104 * This fast table calculation works only if POLY is a prime polynomial
105 * in the field of integers modulo 2. Since the coefficients of a
106 * 32-bit polynomial won't fit in a 32-bit word, the high-order bit is
107 * implicit. IT MUST ALSO BE THE CASE that the coefficients of orders
108 * 31 down to 25 are zero. Happily, we have candidates, from
109 * E. J. Watson, "Primitive Polynomials (Mod 2)", Math. Comp. 16 (1962):
110 * x^32 + x^7 + x^5 + x^3 + x^2 + x^1 + x^0
113 * We reverse the bits to get:
114 * 111101010000000000000000000000001 but drop the last 1
116 * 010010000000000000000000000000001 ditto, for 31-bit crc
120 #define POLY 0x48000000L /* 31-bit polynomial (avoids sign problems) */
122 static guint CrcTable
[128];
125 - crcinit - initialize tables for hash function
127 static void crcinit(void)
132 for (i
= 0; i
< 128; ++i
) {
134 for (j
= 7 - 1; j
>= 0; --j
)
142 - hash - Honeyman's nice hashing function
144 static guint
honeyman_hash(gconstpointer key
)
146 const gchar
*name
= (const gchar
*) key
;
150 g_assert (name
!= NULL
);
151 g_assert (*name
!= 0);
156 sum
= (sum
>> 7) ^ CrcTable
[(sum
^ (*name
++)) & 0x7f];
163 static gint
second_hash_cmp (gconstpointer a
, gconstpointer b
)
165 gint rc
= (strcmp (a
, b
) == 0);
172 static guint
one_hash(gconstpointer key
)
178 static void not_even_foreach (gpointer key
,
182 const char *_key
= (const char *) key
;
183 const char *_value
= (const char *) value
;
187 g_assert (_key
!= NULL
);
188 g_assert (*_key
!= 0);
189 g_assert (_value
!= NULL
);
190 g_assert (*_value
!= 0);
193 g_assert (atoi (_key
) > 0);
195 sprintf (val
, "%d value", i
);
196 g_assert (strcmp (_value
, val
) == 0);
198 g_assert ((i
% 2) != 0);
203 static gboolean
remove_even_foreach (gpointer key
,
207 const char *_key
= (const char *) key
;
208 const char *_value
= (const char *) value
;
212 g_assert (_key
!= NULL
);
213 g_assert (*_key
!= 0);
214 g_assert (_value
!= NULL
);
215 g_assert (*_value
!= 0);
220 sprintf (val
, "%d value", i
);
221 g_assert (strcmp (_value
, val
) == 0);
223 return ((i
% 2) == 0) ? TRUE
: FALSE
;
229 static void second_hash_test (gboolean simple_hash
)
232 char key
[20] = "", val
[20]="", *v
, *orig_key
, *orig_val
;
238 h
= g_hash_table_new (simple_hash
? one_hash
: honeyman_hash
,
240 g_assert (h
!= NULL
);
243 sprintf (key
, "%d", i
);
244 g_assert (atoi (key
) == i
);
246 sprintf (val
, "%d value", i
);
247 g_assert (atoi (val
) == i
);
249 g_hash_table_insert (h
, g_strdup (key
), g_strdup (val
));
252 g_assert (g_hash_table_size (h
) == 20);
256 sprintf (key
, "%d", i
);
257 g_assert (atoi(key
) == i
);
259 v
= (char *) g_hash_table_lookup (h
, key
);
261 g_assert (v
!= NULL
);
263 g_assert (atoi (v
) == i
);
266 /**** future test stuff, yet to be debugged
267 sprintf (key, "%d", 3);
268 g_hash_table_remove (h, key);
269 g_hash_table_foreach_remove (h, remove_even_foreach, NULL);
270 g_hash_table_foreach (h, not_even_foreach, NULL);
275 if (((i
% 2) == 0) || (i
== 3))
278 sprintf (key
, "%d", i
);
279 g_assert (atoi(key
) == i
);
281 sprintf (val
, "%d value", i
);
282 g_assert (atoi (val
) == i
);
284 orig_key
= orig_val
= NULL
;
285 found
= g_hash_table_lookup_extended (h
, key
,
287 (gpointer
)&orig_val
);
290 g_assert (orig_key
!= NULL
);
291 g_assert (strcmp (key
, orig_key
) == 0);
294 g_assert (orig_val
!= NULL
);
295 g_assert (strcmp (val
, orig_val
) == 0);
299 g_hash_table_destroy (h
);
303 static void direct_hash_test (void)
308 h
= g_hash_table_new (NULL
, NULL
);
309 g_assert (h
!= NULL
);
310 for (i
=1; i
<=20; i
++)
312 g_hash_table_insert (h
, GINT_TO_POINTER (i
),
313 GINT_TO_POINTER (i
+ 42));
316 g_assert (g_hash_table_size (h
) == 20);
318 for (i
=1; i
<=20; i
++)
320 rc
= GPOINTER_TO_INT (
321 g_hash_table_lookup (h
, GINT_TO_POINTER (i
)));
324 g_assert ((rc
- 42) == i
);
327 g_hash_table_destroy (h
);
336 GHashTable
*hash_table
;
339 hash_table
= g_hash_table_new (my_hash
, my_hash_compare
);
340 for (i
= 0; i
< 10000; i
++)
343 g_hash_table_insert (hash_table
, &array
[i
], &array
[i
]);
345 g_hash_table_foreach (hash_table
, my_hash_callback
, NULL
);
347 for (i
= 0; i
< 10000; i
++)
349 g_assert_not_reached();
351 for (i
= 0; i
< 10000; i
++)
352 g_hash_table_remove (hash_table
, &array
[i
]);
354 for (i
= 0; i
< 10000; i
++)
357 g_hash_table_insert (hash_table
, &array
[i
], &array
[i
]);
360 if (g_hash_table_foreach_remove (hash_table
, my_hash_callback_remove
, NULL
) != 5000 ||
361 g_hash_table_size (hash_table
) != 5000)
362 g_assert_not_reached();
364 g_hash_table_foreach (hash_table
, my_hash_callback_remove_test
, NULL
);
367 g_hash_table_destroy (hash_table
);
369 second_hash_test (TRUE
);
370 second_hash_test (FALSE
);