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authormarha <marha@users.sourceforge.net>2011-10-05 17:37:34 +0200
committermarha <marha@users.sourceforge.net>2011-10-05 17:37:34 +0200
commitf7025b4baa1ba35ee796785641f04eac5bedb0a6 (patch)
tree3df62b7b501a478e212397883657a8a8be4db7a3 /mesalib/src/mesa/main/hash.c
parent60adbfdea1ee754341d64454274e7aa83bae8971 (diff)
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mkfontscale pixman xserver xtrans libX11 libXdmcp libxcb libXmu mesa git update 5 oct 2011
Diffstat (limited to 'mesalib/src/mesa/main/hash.c')
-rw-r--r--mesalib/src/mesa/main/hash.c1094
1 files changed, 547 insertions, 547 deletions
diff --git a/mesalib/src/mesa/main/hash.c b/mesalib/src/mesa/main/hash.c
index 63f5c90fa..4b250ad54 100644
--- a/mesalib/src/mesa/main/hash.c
+++ b/mesalib/src/mesa/main/hash.c
@@ -1,547 +1,547 @@
-/**
- * \file hash.c
- * Generic hash table.
- *
- * Used for display lists, texture objects, vertex/fragment programs,
- * buffer objects, etc. The hash functions are thread-safe.
- *
- * \note key=0 is illegal.
- *
- * \author Brian Paul
- */
-
-/*
- * Mesa 3-D graphics library
- * Version: 6.5.1
- *
- * Copyright (C) 1999-2006 Brian Paul All Rights Reserved.
- *
- * Permission is hereby granted, free of charge, to any person obtaining a
- * copy of this software and associated documentation files (the "Software"),
- * to deal in the Software without restriction, including without limitation
- * the rights to use, copy, modify, merge, publish, distribute, sublicense,
- * and/or sell copies of the Software, and to permit persons to whom the
- * Software is furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included
- * in all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
- * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
- * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
- * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
- * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- */
-
-
-#include "glheader.h"
-#include "imports.h"
-#include "glapi/glthread.h"
-#include "hash.h"
-
-
-#define TABLE_SIZE 1023 /**< Size of lookup table/array */
-
-#define HASH_FUNC(K) ((K) % TABLE_SIZE)
-
-
-/**
- * An entry in the hash table.
- */
-struct HashEntry {
- GLuint Key; /**< the entry's key */
- void *Data; /**< the entry's data */
- struct HashEntry *Next; /**< pointer to next entry */
-};
-
-
-/**
- * The hash table data structure.
- */
-struct _mesa_HashTable {
- struct HashEntry *Table[TABLE_SIZE]; /**< the lookup table */
- GLuint MaxKey; /**< highest key inserted so far */
- _glthread_Mutex Mutex; /**< mutual exclusion lock */
- _glthread_Mutex WalkMutex; /**< for _mesa_HashWalk() */
- GLboolean InDeleteAll; /**< Debug check */
-};
-
-
-
-/**
- * Create a new hash table.
- *
- * \return pointer to a new, empty hash table.
- */
-struct _mesa_HashTable *
-_mesa_NewHashTable(void)
-{
- struct _mesa_HashTable *table = CALLOC_STRUCT(_mesa_HashTable);
- if (table) {
- _glthread_INIT_MUTEX(table->Mutex);
- _glthread_INIT_MUTEX(table->WalkMutex);
- }
- return table;
-}
-
-
-
-/**
- * Delete a hash table.
- * Frees each entry on the hash table and then the hash table structure itself.
- * Note that the caller should have already traversed the table and deleted
- * the objects in the table (i.e. We don't free the entries' data pointer).
- *
- * \param table the hash table to delete.
- */
-void
-_mesa_DeleteHashTable(struct _mesa_HashTable *table)
-{
- GLuint pos;
- assert(table);
- for (pos = 0; pos < TABLE_SIZE; pos++) {
- struct HashEntry *entry = table->Table[pos];
- while (entry) {
- struct HashEntry *next = entry->Next;
- if (entry->Data) {
- _mesa_problem(NULL,
- "In _mesa_DeleteHashTable, found non-freed data");
- }
- free(entry);
- entry = next;
- }
- }
- _glthread_DESTROY_MUTEX(table->Mutex);
- _glthread_DESTROY_MUTEX(table->WalkMutex);
- free(table);
-}
-
-
-
-/**
- * Lookup an entry in the hash table, without locking.
- * \sa _mesa_HashLookup
- */
-static INLINE void *
-_mesa_HashLookup_unlocked(struct _mesa_HashTable *table, GLuint key)
-{
- GLuint pos;
- const struct HashEntry *entry;
-
- assert(table);
- assert(key);
-
- pos = HASH_FUNC(key);
- entry = table->Table[pos];
- while (entry) {
- if (entry->Key == key) {
- return entry->Data;
- }
- entry = entry->Next;
- }
- return NULL;
-}
-
-
-/**
- * Lookup an entry in the hash table.
- *
- * \param table the hash table.
- * \param key the key.
- *
- * \return pointer to user's data or NULL if key not in table
- */
-void *
-_mesa_HashLookup(struct _mesa_HashTable *table, GLuint key)
-{
- void *res;
- assert(table);
- _glthread_LOCK_MUTEX(table->Mutex);
- res = _mesa_HashLookup_unlocked(table, key);
- _glthread_UNLOCK_MUTEX(table->Mutex);
- return res;
-}
-
-
-/**
- * Insert a key/pointer pair into the hash table.
- * If an entry with this key already exists we'll replace the existing entry.
- *
- * \param table the hash table.
- * \param key the key (not zero).
- * \param data pointer to user data.
- */
-void
-_mesa_HashInsert(struct _mesa_HashTable *table, GLuint key, void *data)
-{
- /* search for existing entry with this key */
- GLuint pos;
- struct HashEntry *entry;
-
- assert(table);
- assert(key);
-
- _glthread_LOCK_MUTEX(table->Mutex);
-
- if (key > table->MaxKey)
- table->MaxKey = key;
-
- pos = HASH_FUNC(key);
-
- /* check if replacing an existing entry with same key */
- for (entry = table->Table[pos]; entry; entry = entry->Next) {
- if (entry->Key == key) {
- /* replace entry's data */
-#if 0 /* not sure this check is always valid */
- if (entry->Data) {
- _mesa_problem(NULL, "Memory leak detected in _mesa_HashInsert");
- }
-#endif
- entry->Data = data;
- _glthread_UNLOCK_MUTEX(table->Mutex);
- return;
- }
- }
-
- /* alloc and insert new table entry */
- entry = MALLOC_STRUCT(HashEntry);
- if (entry) {
- entry->Key = key;
- entry->Data = data;
- entry->Next = table->Table[pos];
- table->Table[pos] = entry;
- }
-
- _glthread_UNLOCK_MUTEX(table->Mutex);
-}
-
-
-
-/**
- * Remove an entry from the hash table.
- *
- * \param table the hash table.
- * \param key key of entry to remove.
- *
- * While holding the hash table's lock, searches the entry with the matching
- * key and unlinks it.
- */
-void
-_mesa_HashRemove(struct _mesa_HashTable *table, GLuint key)
-{
- GLuint pos;
- struct HashEntry *entry, *prev;
-
- assert(table);
- assert(key);
-
- /* have to check this outside of mutex lock */
- if (table->InDeleteAll) {
- _mesa_problem(NULL, "_mesa_HashRemove illegally called from "
- "_mesa_HashDeleteAll callback function");
- return;
- }
-
- _glthread_LOCK_MUTEX(table->Mutex);
-
- pos = HASH_FUNC(key);
- prev = NULL;
- entry = table->Table[pos];
- while (entry) {
- if (entry->Key == key) {
- /* found it! */
- if (prev) {
- prev->Next = entry->Next;
- }
- else {
- table->Table[pos] = entry->Next;
- }
- free(entry);
- _glthread_UNLOCK_MUTEX(table->Mutex);
- return;
- }
- prev = entry;
- entry = entry->Next;
- }
-
- _glthread_UNLOCK_MUTEX(table->Mutex);
-}
-
-
-
-/**
- * Delete all entries in a hash table, but don't delete the table itself.
- * Invoke the given callback function for each table entry.
- *
- * \param table the hash table to delete
- * \param callback the callback function
- * \param userData arbitrary pointer to pass along to the callback
- * (this is typically a struct gl_context pointer)
- */
-void
-_mesa_HashDeleteAll(struct _mesa_HashTable *table,
- void (*callback)(GLuint key, void *data, void *userData),
- void *userData)
-{
- GLuint pos;
- ASSERT(table);
- ASSERT(callback);
- _glthread_LOCK_MUTEX(table->Mutex);
- table->InDeleteAll = GL_TRUE;
- for (pos = 0; pos < TABLE_SIZE; pos++) {
- struct HashEntry *entry, *next;
- for (entry = table->Table[pos]; entry; entry = next) {
- callback(entry->Key, entry->Data, userData);
- next = entry->Next;
- free(entry);
- }
- table->Table[pos] = NULL;
- }
- table->InDeleteAll = GL_FALSE;
- _glthread_UNLOCK_MUTEX(table->Mutex);
-}
-
-
-/**
- * Walk over all entries in a hash table, calling callback function for each.
- * Note: we use a separate mutex in this function to avoid a recursive
- * locking deadlock (in case the callback calls _mesa_HashRemove()) and to
- * prevent multiple threads/contexts from getting tangled up.
- * A lock-less version of this function could be used when the table will
- * not be modified.
- * \param table the hash table to walk
- * \param callback the callback function
- * \param userData arbitrary pointer to pass along to the callback
- * (this is typically a struct gl_context pointer)
- */
-void
-_mesa_HashWalk(const struct _mesa_HashTable *table,
- void (*callback)(GLuint key, void *data, void *userData),
- void *userData)
-{
- /* cast-away const */
- struct _mesa_HashTable *table2 = (struct _mesa_HashTable *) table;
- GLuint pos;
- ASSERT(table);
- ASSERT(callback);
- _glthread_LOCK_MUTEX(table2->WalkMutex);
- for (pos = 0; pos < TABLE_SIZE; pos++) {
- struct HashEntry *entry, *next;
- for (entry = table->Table[pos]; entry; entry = next) {
- /* save 'next' pointer now in case the callback deletes the entry */
- next = entry->Next;
- callback(entry->Key, entry->Data, userData);
- }
- }
- _glthread_UNLOCK_MUTEX(table2->WalkMutex);
-}
-
-
-/**
- * Return the key of the "first" entry in the hash table.
- * While holding the lock, walks through all table positions until finding
- * the first entry of the first non-empty one.
- *
- * \param table the hash table
- * \return key for the "first" entry in the hash table.
- */
-GLuint
-_mesa_HashFirstEntry(struct _mesa_HashTable *table)
-{
- GLuint pos;
- assert(table);
- _glthread_LOCK_MUTEX(table->Mutex);
- for (pos = 0; pos < TABLE_SIZE; pos++) {
- if (table->Table[pos]) {
- _glthread_UNLOCK_MUTEX(table->Mutex);
- return table->Table[pos]->Key;
- }
- }
- _glthread_UNLOCK_MUTEX(table->Mutex);
- return 0;
-}
-
-
-/**
- * Given a hash table key, return the next key. This is used to walk
- * over all entries in the table. Note that the keys returned during
- * walking won't be in any particular order.
- * \return next hash key or 0 if end of table.
- */
-GLuint
-_mesa_HashNextEntry(const struct _mesa_HashTable *table, GLuint key)
-{
- const struct HashEntry *entry;
- GLuint pos;
-
- assert(table);
- assert(key);
-
- /* Find the entry with given key */
- pos = HASH_FUNC(key);
- for (entry = table->Table[pos]; entry ; entry = entry->Next) {
- if (entry->Key == key) {
- break;
- }
- }
-
- if (!entry) {
- /* the given key was not found, so we can't find the next entry */
- return 0;
- }
-
- if (entry->Next) {
- /* return next in linked list */
- return entry->Next->Key;
- }
- else {
- /* look for next non-empty table slot */
- pos++;
- while (pos < TABLE_SIZE) {
- if (table->Table[pos]) {
- return table->Table[pos]->Key;
- }
- pos++;
- }
- return 0;
- }
-}
-
-
-/**
- * Dump contents of hash table for debugging.
- *
- * \param table the hash table.
- */
-void
-_mesa_HashPrint(const struct _mesa_HashTable *table)
-{
- GLuint pos;
- assert(table);
- for (pos = 0; pos < TABLE_SIZE; pos++) {
- const struct HashEntry *entry = table->Table[pos];
- while (entry) {
- _mesa_debug(NULL, "%u %p\n", entry->Key, entry->Data);
- entry = entry->Next;
- }
- }
-}
-
-
-
-/**
- * Find a block of adjacent unused hash keys.
- *
- * \param table the hash table.
- * \param numKeys number of keys needed.
- *
- * \return Starting key of free block or 0 if failure.
- *
- * If there are enough free keys between the maximum key existing in the table
- * (_mesa_HashTable::MaxKey) and the maximum key possible, then simply return
- * the adjacent key. Otherwise do a full search for a free key block in the
- * allowable key range.
- */
-GLuint
-_mesa_HashFindFreeKeyBlock(struct _mesa_HashTable *table, GLuint numKeys)
-{
- const GLuint maxKey = ~((GLuint) 0);
- _glthread_LOCK_MUTEX(table->Mutex);
- if (maxKey - numKeys > table->MaxKey) {
- /* the quick solution */
- _glthread_UNLOCK_MUTEX(table->Mutex);
- return table->MaxKey + 1;
- }
- else {
- /* the slow solution */
- GLuint freeCount = 0;
- GLuint freeStart = 1;
- GLuint key;
- for (key = 1; key != maxKey; key++) {
- if (_mesa_HashLookup_unlocked(table, key)) {
- /* darn, this key is already in use */
- freeCount = 0;
- freeStart = key+1;
- }
- else {
- /* this key not in use, check if we've found enough */
- freeCount++;
- if (freeCount == numKeys) {
- _glthread_UNLOCK_MUTEX(table->Mutex);
- return freeStart;
- }
- }
- }
- /* cannot allocate a block of numKeys consecutive keys */
- _glthread_UNLOCK_MUTEX(table->Mutex);
- return 0;
- }
-}
-
-
-#if 0 /* debug only */
-
-/**
- * Test walking over all the entries in a hash table.
- */
-static void
-test_hash_walking(void)
-{
- struct _mesa_HashTable *t = _mesa_NewHashTable();
- const GLuint limit = 50000;
- GLuint i;
-
- /* create some entries */
- for (i = 0; i < limit; i++) {
- GLuint dummy;
- GLuint k = (rand() % (limit * 10)) + 1;
- while (_mesa_HashLookup(t, k)) {
- /* id already in use, try another */
- k = (rand() % (limit * 10)) + 1;
- }
- _mesa_HashInsert(t, k, &dummy);
- }
-
- /* walk over all entries */
- {
- GLuint k = _mesa_HashFirstEntry(t);
- GLuint count = 0;
- while (k) {
- GLuint knext = _mesa_HashNextEntry(t, k);
- assert(knext != k);
- _mesa_HashRemove(t, k);
- count++;
- k = knext;
- }
- assert(count == limit);
- k = _mesa_HashFirstEntry(t);
- assert(k==0);
- }
-
- _mesa_DeleteHashTable(t);
-}
-
-
-void
-_mesa_test_hash_functions(void)
-{
- int a, b, c;
- struct _mesa_HashTable *t;
-
- t = _mesa_NewHashTable();
- _mesa_HashInsert(t, 501, &a);
- _mesa_HashInsert(t, 10, &c);
- _mesa_HashInsert(t, 0xfffffff8, &b);
- /*_mesa_HashPrint(t);*/
-
- assert(_mesa_HashLookup(t,501));
- assert(!_mesa_HashLookup(t,1313));
- assert(_mesa_HashFindFreeKeyBlock(t, 100));
-
- _mesa_DeleteHashTable(t);
-
- test_hash_walking();
-}
-
-#endif
+/**
+ * \file hash.c
+ * Generic hash table.
+ *
+ * Used for display lists, texture objects, vertex/fragment programs,
+ * buffer objects, etc. The hash functions are thread-safe.
+ *
+ * \note key=0 is illegal.
+ *
+ * \author Brian Paul
+ */
+
+/*
+ * Mesa 3-D graphics library
+ * Version: 6.5.1
+ *
+ * Copyright (C) 1999-2006 Brian Paul All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+
+#include "glheader.h"
+#include "imports.h"
+#include "glapi/glthread.h"
+#include "hash.h"
+
+
+#define TABLE_SIZE 1023 /**< Size of lookup table/array */
+
+#define HASH_FUNC(K) ((K) % TABLE_SIZE)
+
+
+/**
+ * An entry in the hash table.
+ */
+struct HashEntry {
+ GLuint Key; /**< the entry's key */
+ void *Data; /**< the entry's data */
+ struct HashEntry *Next; /**< pointer to next entry */
+};
+
+
+/**
+ * The hash table data structure.
+ */
+struct _mesa_HashTable {
+ struct HashEntry *Table[TABLE_SIZE]; /**< the lookup table */
+ GLuint MaxKey; /**< highest key inserted so far */
+ _glthread_Mutex Mutex; /**< mutual exclusion lock */
+ _glthread_Mutex WalkMutex; /**< for _mesa_HashWalk() */
+ GLboolean InDeleteAll; /**< Debug check */
+};
+
+
+
+/**
+ * Create a new hash table.
+ *
+ * \return pointer to a new, empty hash table.
+ */
+struct _mesa_HashTable *
+_mesa_NewHashTable(void)
+{
+ struct _mesa_HashTable *table = CALLOC_STRUCT(_mesa_HashTable);
+ if (table) {
+ _glthread_INIT_MUTEX(table->Mutex);
+ _glthread_INIT_MUTEX(table->WalkMutex);
+ }
+ return table;
+}
+
+
+
+/**
+ * Delete a hash table.
+ * Frees each entry on the hash table and then the hash table structure itself.
+ * Note that the caller should have already traversed the table and deleted
+ * the objects in the table (i.e. We don't free the entries' data pointer).
+ *
+ * \param table the hash table to delete.
+ */
+void
+_mesa_DeleteHashTable(struct _mesa_HashTable *table)
+{
+ GLuint pos;
+ assert(table);
+ for (pos = 0; pos < TABLE_SIZE; pos++) {
+ struct HashEntry *entry = table->Table[pos];
+ while (entry) {
+ struct HashEntry *next = entry->Next;
+ if (entry->Data) {
+ _mesa_problem(NULL,
+ "In _mesa_DeleteHashTable, found non-freed data");
+ }
+ free(entry);
+ entry = next;
+ }
+ }
+ _glthread_DESTROY_MUTEX(table->Mutex);
+ _glthread_DESTROY_MUTEX(table->WalkMutex);
+ free(table);
+}
+
+
+
+/**
+ * Lookup an entry in the hash table, without locking.
+ * \sa _mesa_HashLookup
+ */
+static inline void *
+_mesa_HashLookup_unlocked(struct _mesa_HashTable *table, GLuint key)
+{
+ GLuint pos;
+ const struct HashEntry *entry;
+
+ assert(table);
+ assert(key);
+
+ pos = HASH_FUNC(key);
+ entry = table->Table[pos];
+ while (entry) {
+ if (entry->Key == key) {
+ return entry->Data;
+ }
+ entry = entry->Next;
+ }
+ return NULL;
+}
+
+
+/**
+ * Lookup an entry in the hash table.
+ *
+ * \param table the hash table.
+ * \param key the key.
+ *
+ * \return pointer to user's data or NULL if key not in table
+ */
+void *
+_mesa_HashLookup(struct _mesa_HashTable *table, GLuint key)
+{
+ void *res;
+ assert(table);
+ _glthread_LOCK_MUTEX(table->Mutex);
+ res = _mesa_HashLookup_unlocked(table, key);
+ _glthread_UNLOCK_MUTEX(table->Mutex);
+ return res;
+}
+
+
+/**
+ * Insert a key/pointer pair into the hash table.
+ * If an entry with this key already exists we'll replace the existing entry.
+ *
+ * \param table the hash table.
+ * \param key the key (not zero).
+ * \param data pointer to user data.
+ */
+void
+_mesa_HashInsert(struct _mesa_HashTable *table, GLuint key, void *data)
+{
+ /* search for existing entry with this key */
+ GLuint pos;
+ struct HashEntry *entry;
+
+ assert(table);
+ assert(key);
+
+ _glthread_LOCK_MUTEX(table->Mutex);
+
+ if (key > table->MaxKey)
+ table->MaxKey = key;
+
+ pos = HASH_FUNC(key);
+
+ /* check if replacing an existing entry with same key */
+ for (entry = table->Table[pos]; entry; entry = entry->Next) {
+ if (entry->Key == key) {
+ /* replace entry's data */
+#if 0 /* not sure this check is always valid */
+ if (entry->Data) {
+ _mesa_problem(NULL, "Memory leak detected in _mesa_HashInsert");
+ }
+#endif
+ entry->Data = data;
+ _glthread_UNLOCK_MUTEX(table->Mutex);
+ return;
+ }
+ }
+
+ /* alloc and insert new table entry */
+ entry = MALLOC_STRUCT(HashEntry);
+ if (entry) {
+ entry->Key = key;
+ entry->Data = data;
+ entry->Next = table->Table[pos];
+ table->Table[pos] = entry;
+ }
+
+ _glthread_UNLOCK_MUTEX(table->Mutex);
+}
+
+
+
+/**
+ * Remove an entry from the hash table.
+ *
+ * \param table the hash table.
+ * \param key key of entry to remove.
+ *
+ * While holding the hash table's lock, searches the entry with the matching
+ * key and unlinks it.
+ */
+void
+_mesa_HashRemove(struct _mesa_HashTable *table, GLuint key)
+{
+ GLuint pos;
+ struct HashEntry *entry, *prev;
+
+ assert(table);
+ assert(key);
+
+ /* have to check this outside of mutex lock */
+ if (table->InDeleteAll) {
+ _mesa_problem(NULL, "_mesa_HashRemove illegally called from "
+ "_mesa_HashDeleteAll callback function");
+ return;
+ }
+
+ _glthread_LOCK_MUTEX(table->Mutex);
+
+ pos = HASH_FUNC(key);
+ prev = NULL;
+ entry = table->Table[pos];
+ while (entry) {
+ if (entry->Key == key) {
+ /* found it! */
+ if (prev) {
+ prev->Next = entry->Next;
+ }
+ else {
+ table->Table[pos] = entry->Next;
+ }
+ free(entry);
+ _glthread_UNLOCK_MUTEX(table->Mutex);
+ return;
+ }
+ prev = entry;
+ entry = entry->Next;
+ }
+
+ _glthread_UNLOCK_MUTEX(table->Mutex);
+}
+
+
+
+/**
+ * Delete all entries in a hash table, but don't delete the table itself.
+ * Invoke the given callback function for each table entry.
+ *
+ * \param table the hash table to delete
+ * \param callback the callback function
+ * \param userData arbitrary pointer to pass along to the callback
+ * (this is typically a struct gl_context pointer)
+ */
+void
+_mesa_HashDeleteAll(struct _mesa_HashTable *table,
+ void (*callback)(GLuint key, void *data, void *userData),
+ void *userData)
+{
+ GLuint pos;
+ ASSERT(table);
+ ASSERT(callback);
+ _glthread_LOCK_MUTEX(table->Mutex);
+ table->InDeleteAll = GL_TRUE;
+ for (pos = 0; pos < TABLE_SIZE; pos++) {
+ struct HashEntry *entry, *next;
+ for (entry = table->Table[pos]; entry; entry = next) {
+ callback(entry->Key, entry->Data, userData);
+ next = entry->Next;
+ free(entry);
+ }
+ table->Table[pos] = NULL;
+ }
+ table->InDeleteAll = GL_FALSE;
+ _glthread_UNLOCK_MUTEX(table->Mutex);
+}
+
+
+/**
+ * Walk over all entries in a hash table, calling callback function for each.
+ * Note: we use a separate mutex in this function to avoid a recursive
+ * locking deadlock (in case the callback calls _mesa_HashRemove()) and to
+ * prevent multiple threads/contexts from getting tangled up.
+ * A lock-less version of this function could be used when the table will
+ * not be modified.
+ * \param table the hash table to walk
+ * \param callback the callback function
+ * \param userData arbitrary pointer to pass along to the callback
+ * (this is typically a struct gl_context pointer)
+ */
+void
+_mesa_HashWalk(const struct _mesa_HashTable *table,
+ void (*callback)(GLuint key, void *data, void *userData),
+ void *userData)
+{
+ /* cast-away const */
+ struct _mesa_HashTable *table2 = (struct _mesa_HashTable *) table;
+ GLuint pos;
+ ASSERT(table);
+ ASSERT(callback);
+ _glthread_LOCK_MUTEX(table2->WalkMutex);
+ for (pos = 0; pos < TABLE_SIZE; pos++) {
+ struct HashEntry *entry, *next;
+ for (entry = table->Table[pos]; entry; entry = next) {
+ /* save 'next' pointer now in case the callback deletes the entry */
+ next = entry->Next;
+ callback(entry->Key, entry->Data, userData);
+ }
+ }
+ _glthread_UNLOCK_MUTEX(table2->WalkMutex);
+}
+
+
+/**
+ * Return the key of the "first" entry in the hash table.
+ * While holding the lock, walks through all table positions until finding
+ * the first entry of the first non-empty one.
+ *
+ * \param table the hash table
+ * \return key for the "first" entry in the hash table.
+ */
+GLuint
+_mesa_HashFirstEntry(struct _mesa_HashTable *table)
+{
+ GLuint pos;
+ assert(table);
+ _glthread_LOCK_MUTEX(table->Mutex);
+ for (pos = 0; pos < TABLE_SIZE; pos++) {
+ if (table->Table[pos]) {
+ _glthread_UNLOCK_MUTEX(table->Mutex);
+ return table->Table[pos]->Key;
+ }
+ }
+ _glthread_UNLOCK_MUTEX(table->Mutex);
+ return 0;
+}
+
+
+/**
+ * Given a hash table key, return the next key. This is used to walk
+ * over all entries in the table. Note that the keys returned during
+ * walking won't be in any particular order.
+ * \return next hash key or 0 if end of table.
+ */
+GLuint
+_mesa_HashNextEntry(const struct _mesa_HashTable *table, GLuint key)
+{
+ const struct HashEntry *entry;
+ GLuint pos;
+
+ assert(table);
+ assert(key);
+
+ /* Find the entry with given key */
+ pos = HASH_FUNC(key);
+ for (entry = table->Table[pos]; entry ; entry = entry->Next) {
+ if (entry->Key == key) {
+ break;
+ }
+ }
+
+ if (!entry) {
+ /* the given key was not found, so we can't find the next entry */
+ return 0;
+ }
+
+ if (entry->Next) {
+ /* return next in linked list */
+ return entry->Next->Key;
+ }
+ else {
+ /* look for next non-empty table slot */
+ pos++;
+ while (pos < TABLE_SIZE) {
+ if (table->Table[pos]) {
+ return table->Table[pos]->Key;
+ }
+ pos++;
+ }
+ return 0;
+ }
+}
+
+
+/**
+ * Dump contents of hash table for debugging.
+ *
+ * \param table the hash table.
+ */
+void
+_mesa_HashPrint(const struct _mesa_HashTable *table)
+{
+ GLuint pos;
+ assert(table);
+ for (pos = 0; pos < TABLE_SIZE; pos++) {
+ const struct HashEntry *entry = table->Table[pos];
+ while (entry) {
+ _mesa_debug(NULL, "%u %p\n", entry->Key, entry->Data);
+ entry = entry->Next;
+ }
+ }
+}
+
+
+
+/**
+ * Find a block of adjacent unused hash keys.
+ *
+ * \param table the hash table.
+ * \param numKeys number of keys needed.
+ *
+ * \return Starting key of free block or 0 if failure.
+ *
+ * If there are enough free keys between the maximum key existing in the table
+ * (_mesa_HashTable::MaxKey) and the maximum key possible, then simply return
+ * the adjacent key. Otherwise do a full search for a free key block in the
+ * allowable key range.
+ */
+GLuint
+_mesa_HashFindFreeKeyBlock(struct _mesa_HashTable *table, GLuint numKeys)
+{
+ const GLuint maxKey = ~((GLuint) 0);
+ _glthread_LOCK_MUTEX(table->Mutex);
+ if (maxKey - numKeys > table->MaxKey) {
+ /* the quick solution */
+ _glthread_UNLOCK_MUTEX(table->Mutex);
+ return table->MaxKey + 1;
+ }
+ else {
+ /* the slow solution */
+ GLuint freeCount = 0;
+ GLuint freeStart = 1;
+ GLuint key;
+ for (key = 1; key != maxKey; key++) {
+ if (_mesa_HashLookup_unlocked(table, key)) {
+ /* darn, this key is already in use */
+ freeCount = 0;
+ freeStart = key+1;
+ }
+ else {
+ /* this key not in use, check if we've found enough */
+ freeCount++;
+ if (freeCount == numKeys) {
+ _glthread_UNLOCK_MUTEX(table->Mutex);
+ return freeStart;
+ }
+ }
+ }
+ /* cannot allocate a block of numKeys consecutive keys */
+ _glthread_UNLOCK_MUTEX(table->Mutex);
+ return 0;
+ }
+}
+
+
+#if 0 /* debug only */
+
+/**
+ * Test walking over all the entries in a hash table.
+ */
+static void
+test_hash_walking(void)
+{
+ struct _mesa_HashTable *t = _mesa_NewHashTable();
+ const GLuint limit = 50000;
+ GLuint i;
+
+ /* create some entries */
+ for (i = 0; i < limit; i++) {
+ GLuint dummy;
+ GLuint k = (rand() % (limit * 10)) + 1;
+ while (_mesa_HashLookup(t, k)) {
+ /* id already in use, try another */
+ k = (rand() % (limit * 10)) + 1;
+ }
+ _mesa_HashInsert(t, k, &dummy);
+ }
+
+ /* walk over all entries */
+ {
+ GLuint k = _mesa_HashFirstEntry(t);
+ GLuint count = 0;
+ while (k) {
+ GLuint knext = _mesa_HashNextEntry(t, k);
+ assert(knext != k);
+ _mesa_HashRemove(t, k);
+ count++;
+ k = knext;
+ }
+ assert(count == limit);
+ k = _mesa_HashFirstEntry(t);
+ assert(k==0);
+ }
+
+ _mesa_DeleteHashTable(t);
+}
+
+
+void
+_mesa_test_hash_functions(void)
+{
+ int a, b, c;
+ struct _mesa_HashTable *t;
+
+ t = _mesa_NewHashTable();
+ _mesa_HashInsert(t, 501, &a);
+ _mesa_HashInsert(t, 10, &c);
+ _mesa_HashInsert(t, 0xfffffff8, &b);
+ /*_mesa_HashPrint(t);*/
+
+ assert(_mesa_HashLookup(t,501));
+ assert(!_mesa_HashLookup(t,1313));
+ assert(_mesa_HashFindFreeKeyBlock(t, 100));
+
+ _mesa_DeleteHashTable(t);
+
+ test_hash_walking();
+}
+
+#endif