5 * Used for display lists, texture objects, vertex/fragment programs,
6 * buffer objects, etc. The hash functions are thread-safe.
8 * \note key=0 is illegal.
14 * Mesa 3-D graphics library
16 * Copyright (C) 1999-2006 Brian Paul All Rights Reserved.
18 * Permission is hereby granted, free of charge, to any person obtaining a
19 * copy of this software and associated documentation files (the "Software"),
20 * to deal in the Software without restriction, including without limitation
21 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
22 * and/or sell copies of the Software, and to permit persons to whom the
23 * Software is furnished to do so, subject to the following conditions:
25 * The above copyright notice and this permission notice shall be included
26 * in all copies or substantial portions of the Software.
28 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
29 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
30 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
31 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
32 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
33 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
34 * OTHER DEALINGS IN THE SOFTWARE.
40 #include "util/hash_table.h"
44 * Create a new hash table.
46 * \return pointer to a new, empty hash table.
48 struct _mesa_HashTable
*
49 _mesa_NewHashTable(void)
51 struct _mesa_HashTable
*table
= CALLOC_STRUCT(_mesa_HashTable
);
54 table
->ht
= _mesa_hash_table_create(NULL
, uint_key_hash
,
56 if (table
->ht
== NULL
) {
58 _mesa_error_no_memory(__func__
);
62 _mesa_hash_table_set_deleted_key(table
->ht
, uint_key(DELETED_KEY_VALUE
));
64 * Needs to be recursive, since the callback in _mesa_HashWalk()
65 * is allowed to call _mesa_HashRemove().
67 mtx_init(&table
->Mutex
, mtx_recursive
);
70 _mesa_error_no_memory(__func__
);
79 * Delete a hash table.
80 * Frees each entry on the hash table and then the hash table structure itself.
81 * Note that the caller should have already traversed the table and deleted
82 * the objects in the table (i.e. We don't free the entries' data pointer).
84 * \param table the hash table to delete.
87 _mesa_DeleteHashTable(struct _mesa_HashTable
*table
)
91 if (_mesa_hash_table_next_entry(table
->ht
, NULL
) != NULL
) {
92 _mesa_problem(NULL
, "In _mesa_DeleteHashTable, found non-freed data");
95 _mesa_hash_table_destroy(table
->ht
, NULL
);
97 mtx_destroy(&table
->Mutex
);
104 * Lookup an entry in the hash table, without locking.
105 * \sa _mesa_HashLookup
108 _mesa_HashLookup_unlocked(struct _mesa_HashTable
*table
, GLuint key
)
110 const struct hash_entry
*entry
;
115 if (key
== DELETED_KEY_VALUE
)
116 return table
->deleted_key_data
;
118 entry
= _mesa_hash_table_search_pre_hashed(table
->ht
,
129 * Lookup an entry in the hash table.
131 * \param table the hash table.
132 * \param key the key.
134 * \return pointer to user's data or NULL if key not in table
137 _mesa_HashLookup(struct _mesa_HashTable
*table
, GLuint key
)
140 _mesa_HashLockMutex(table
);
141 res
= _mesa_HashLookup_unlocked(table
, key
);
142 _mesa_HashUnlockMutex(table
);
148 * Lookup an entry in the hash table without locking the mutex.
150 * The hash table mutex must be locked manually by calling
151 * _mesa_HashLockMutex() before calling this function.
153 * \param table the hash table.
154 * \param key the key.
156 * \return pointer to user's data or NULL if key not in table
159 _mesa_HashLookupLocked(struct _mesa_HashTable
*table
, GLuint key
)
161 return _mesa_HashLookup_unlocked(table
, key
);
166 _mesa_HashInsert_unlocked(struct _mesa_HashTable
*table
, GLuint key
, void *data
)
168 uint32_t hash
= uint_hash(key
);
169 struct hash_entry
*entry
;
174 if (key
> table
->MaxKey
)
177 if (key
== DELETED_KEY_VALUE
) {
178 table
->deleted_key_data
= data
;
180 entry
= _mesa_hash_table_search_pre_hashed(table
->ht
, hash
, uint_key(key
));
184 _mesa_hash_table_insert_pre_hashed(table
->ht
, hash
, uint_key(key
), data
);
191 * Insert a key/pointer pair into the hash table without locking the mutex.
192 * If an entry with this key already exists we'll replace the existing entry.
194 * The hash table mutex must be locked manually by calling
195 * _mesa_HashLockMutex() before calling this function.
197 * \param table the hash table.
198 * \param key the key (not zero).
199 * \param data pointer to user data.
202 _mesa_HashInsertLocked(struct _mesa_HashTable
*table
, GLuint key
, void *data
)
204 _mesa_HashInsert_unlocked(table
, key
, data
);
209 * Insert a key/pointer pair into the hash table.
210 * If an entry with this key already exists we'll replace the existing entry.
212 * \param table the hash table.
213 * \param key the key (not zero).
214 * \param data pointer to user data.
217 _mesa_HashInsert(struct _mesa_HashTable
*table
, GLuint key
, void *data
)
219 _mesa_HashLockMutex(table
);
220 _mesa_HashInsert_unlocked(table
, key
, data
);
221 _mesa_HashUnlockMutex(table
);
226 * Remove an entry from the hash table.
228 * \param table the hash table.
229 * \param key key of entry to remove.
231 * While holding the hash table's lock, searches the entry with the matching
232 * key and unlinks it.
235 _mesa_HashRemove_unlocked(struct _mesa_HashTable
*table
, GLuint key
)
237 struct hash_entry
*entry
;
242 /* assert if _mesa_HashRemove illegally called from _mesa_HashDeleteAll
243 * callback function. Have to check this outside of mutex lock.
245 assert(!table
->InDeleteAll
);
247 if (key
== DELETED_KEY_VALUE
) {
248 table
->deleted_key_data
= NULL
;
250 entry
= _mesa_hash_table_search_pre_hashed(table
->ht
,
253 _mesa_hash_table_remove(table
->ht
, entry
);
259 _mesa_HashRemoveLocked(struct _mesa_HashTable
*table
, GLuint key
)
261 _mesa_HashRemove_unlocked(table
, key
);
265 _mesa_HashRemove(struct _mesa_HashTable
*table
, GLuint key
)
267 _mesa_HashLockMutex(table
);
268 _mesa_HashRemove_unlocked(table
, key
);
269 _mesa_HashUnlockMutex(table
);
273 * Delete all entries in a hash table, but don't delete the table itself.
274 * Invoke the given callback function for each table entry.
276 * \param table the hash table to delete
277 * \param callback the callback function
278 * \param userData arbitrary pointer to pass along to the callback
279 * (this is typically a struct gl_context pointer)
282 _mesa_HashDeleteAll(struct _mesa_HashTable
*table
,
283 void (*callback
)(GLuint key
, void *data
, void *userData
),
287 _mesa_HashLockMutex(table
);
288 table
->InDeleteAll
= GL_TRUE
;
289 hash_table_foreach(table
->ht
, entry
) {
290 callback((uintptr_t)entry
->key
, entry
->data
, userData
);
291 _mesa_hash_table_remove(table
->ht
, entry
);
293 if (table
->deleted_key_data
) {
294 callback(DELETED_KEY_VALUE
, table
->deleted_key_data
, userData
);
295 table
->deleted_key_data
= NULL
;
297 table
->InDeleteAll
= GL_FALSE
;
298 _mesa_HashUnlockMutex(table
);
303 * Walk over all entries in a hash table, calling callback function for each.
304 * \param table the hash table to walk
305 * \param callback the callback function
306 * \param userData arbitrary pointer to pass along to the callback
307 * (this is typically a struct gl_context pointer)
310 hash_walk_unlocked(const struct _mesa_HashTable
*table
,
311 void (*callback
)(GLuint key
, void *data
, void *userData
),
317 hash_table_foreach(table
->ht
, entry
) {
318 callback((uintptr_t)entry
->key
, entry
->data
, userData
);
320 if (table
->deleted_key_data
)
321 callback(DELETED_KEY_VALUE
, table
->deleted_key_data
, userData
);
326 _mesa_HashWalk(const struct _mesa_HashTable
*table
,
327 void (*callback
)(GLuint key
, void *data
, void *userData
),
330 /* cast-away const */
331 struct _mesa_HashTable
*table2
= (struct _mesa_HashTable
*) table
;
333 _mesa_HashLockMutex(table2
);
334 hash_walk_unlocked(table
, callback
, userData
);
335 _mesa_HashUnlockMutex(table2
);
339 _mesa_HashWalkLocked(const struct _mesa_HashTable
*table
,
340 void (*callback
)(GLuint key
, void *data
, void *userData
),
343 hash_walk_unlocked(table
, callback
, userData
);
347 debug_print_entry(GLuint key
, void *data
, void *userData
)
349 _mesa_debug(NULL
, "%u %p\n", key
, data
);
353 * Dump contents of hash table for debugging.
355 * \param table the hash table.
358 _mesa_HashPrint(const struct _mesa_HashTable
*table
)
360 if (table
->deleted_key_data
)
361 debug_print_entry(DELETED_KEY_VALUE
, table
->deleted_key_data
, NULL
);
362 _mesa_HashWalk(table
, debug_print_entry
, NULL
);
367 * Find a block of adjacent unused hash keys.
369 * \param table the hash table.
370 * \param numKeys number of keys needed.
372 * \return Starting key of free block or 0 if failure.
374 * If there are enough free keys between the maximum key existing in the table
375 * (_mesa_HashTable::MaxKey) and the maximum key possible, then simply return
376 * the adjacent key. Otherwise do a full search for a free key block in the
377 * allowable key range.
380 _mesa_HashFindFreeKeyBlock(struct _mesa_HashTable
*table
, GLuint numKeys
)
382 const GLuint maxKey
= ~((GLuint
) 0) - 1;
383 if (maxKey
- numKeys
> table
->MaxKey
) {
384 /* the quick solution */
385 return table
->MaxKey
+ 1;
388 /* the slow solution */
389 GLuint freeCount
= 0;
390 GLuint freeStart
= 1;
392 for (key
= 1; key
!= maxKey
; key
++) {
393 if (_mesa_HashLookup_unlocked(table
, key
)) {
394 /* darn, this key is already in use */
399 /* this key not in use, check if we've found enough */
401 if (freeCount
== numKeys
) {
406 /* cannot allocate a block of numKeys consecutive keys */
413 * Return the number of entries in the hash table.
416 _mesa_HashNumEntries(const struct _mesa_HashTable
*table
)
420 if (table
->deleted_key_data
)
423 count
+= _mesa_hash_table_num_entries(table
->ht
);