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/* GLIB - Library of useful routines for C programming
* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/*
* Modified by the GLib Team and others 1997-2000. See the AUTHORS
* file for a list of people on the GLib Team. See the ChangeLog
* files for a list of changes. These files are distributed with
* GLib at ftp://ftp.gtk.org/pub/gtk/.
*/
/*
* MT safe
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "glib.h"
#define HASH_TABLE_MIN_SIZE 11
#define HASH_TABLE_MAX_SIZE 13845163
typedef struct _GHashNode GHashNode;
struct _GHashNode
{
gpointer key;
gpointer value;
GHashNode *next;
};
struct _GHashTable
{
gint size;
gint nnodes;
GHashNode **nodes;
GHashFunc hash_func;
GEqualFunc key_equal_func;
GDestroyNotify key_destroy_func;
GDestroyNotify value_destroy_func;
};
static void g_hash_table_resize (GHashTable *hash_table);
static GHashNode** g_hash_table_lookup_node (GHashTable *hash_table,
gconstpointer key);
static GHashNode* g_hash_node_new (gpointer key,
gpointer value);
static void g_hash_node_destroy (GHashNode *hash_node,
GDestroyNotify key_destroy_func,
GDestroyNotify value_destroy_func);
static void g_hash_nodes_destroy (GHashNode *hash_node,
GDestroyNotify key_destroy_func,
GDestroyNotify value_destroy_func);
static guint g_hash_table_foreach_remove_or_steal (GHashTable *hash_table,
GHRFunc func,
gpointer user_data,
gboolean notify);
G_LOCK_DEFINE_STATIC (g_hash_global);
static GMemChunk *node_mem_chunk = NULL;
static GHashNode *node_free_list = NULL;
/**
* g_hash_table_new:
* @hash_func: a function to create a hash value from a key.
* Hash values are used to determine where keys are stored within the
* #GHashTable data structure. The g_direct_hash(), g_int_hash() and
* g_str_hash() functions are provided for some common types of keys.
* If hash_func is NULL, g_direct_hash() is used.
* @key_equal_func: a function to check two keys for equality. This is
* used when looking up keys in the #GHashTable. The g_direct_equal(),
* g_int_equal() and g_str_equal() functions are provided for the most
* common types of keys. If @key_equal_func is NULL, keys are compared
* directly in a similar fashion to g_direct_equal(), but without the
* overhead of a function call.
*
* Creates a new #GHashTable.
*
* Return value: a new #GHashTable.
**/
GHashTable*
g_hash_table_new (GHashFunc hash_func,
GEqualFunc key_equal_func)
{
return g_hash_table_new_full (hash_func, key_equal_func, NULL, NULL);
}
/**
* g_hash_table_new_full:
* @hash_func: a function to create a hash value from a key.
* @key_equal_func: a function to check two keys for equality.
* @key_destroy_func: a function to free the memory allocated for the key
* used when removing the entry from the #GHashTable or #NULL if you
* you don't want to supply such a function.
* @value_destroy_func: a function to free the memory allocated for the
* value used when removing the entry from the #GHashTable or #NULL if
* you don't want to supply such a function.
*
* Creates a new #GHashTable like g_hash_table_new() and allows to specify
* functions to free the memory allocated for the key and value that get
* called when removing the entry from the #GHashTable.
*
* Return value: a new #GHashTable.
**/
GHashTable*
g_hash_table_new_full (GHashFunc hash_func,
GEqualFunc key_equal_func,
GDestroyNotify key_destroy_func,
GDestroyNotify value_destroy_func)
{
GHashTable *hash_table;
guint i;
hash_table = g_new (GHashTable, 1);
hash_table->size = HASH_TABLE_MIN_SIZE;
hash_table->nnodes = 0;
hash_table->hash_func = hash_func ? hash_func : g_direct_hash;
hash_table->key_equal_func = key_equal_func;
hash_table->key_destroy_func = key_destroy_func;
hash_table->value_destroy_func = value_destroy_func;
hash_table->nodes = g_new (GHashNode*, hash_table->size);
for (i = 0; i < hash_table->size; i++)
hash_table->nodes[i] = NULL;
return hash_table;
}
/**
* g_hash_table_destroy:
* @hash_table: a #GHashTable.
*
* Destroys the #GHashTable. If keys and/or values are dynamically
* allocated, you should either free them first or create the #GHashTable
* using g_hash_table_new_full(). In the latter case the destroy functions
* you supplied will be called on all keys and values before destroying
* the #GHashTable.
**/
void
g_hash_table_destroy (GHashTable *hash_table)
{
guint i;
g_return_if_fail (hash_table != NULL);
for (i = 0; i < hash_table->size; i++)
g_hash_nodes_destroy (hash_table->nodes[i],
hash_table->key_destroy_func,
hash_table->value_destroy_func);
g_free (hash_table->nodes);
g_free (hash_table);
}
static inline GHashNode**
g_hash_table_lookup_node (GHashTable *hash_table,
gconstpointer key)
{
GHashNode **node;
node = &hash_table->nodes
[(* hash_table->hash_func) (key) % hash_table->size];
/* Hash table lookup needs to be fast.
* We therefore remove the extra conditional of testing
* whether to call the key_equal_func or not from
* the inner loop.
*/
if (hash_table->key_equal_func)
while (*node && !(*hash_table->key_equal_func) ((*node)->key, key))
node = &(*node)->next;
else
while (*node && (*node)->key != key)
node = &(*node)->next;
return node;
}
/**
* g_hash_table_lookup:
* @hash_table: a #GHashTable.
* @key: the key to look up.
*
* Looks up a key in a #GHashTable.
*
* Return value: the associated value, or NULL if the key is not found.
**/
gpointer
g_hash_table_lookup (GHashTable *hash_table,
gconstpointer key)
{
GHashNode *node;
g_return_val_if_fail (hash_table != NULL, NULL);
node = *g_hash_table_lookup_node (hash_table, key);
return node ? node->value : NULL;
}
/**
* g_hash_table_lookup_extended:
* @hash_table: a #GHashTable.
* @lookup_key: the key to look up.
* @orig_key: returns the original key.
* @value: returns the value associated with the key.
*
* Looks up a key in the #GHashTable, returning the original key and the
* associated value and a gboolean which is TRUE if the key was found. This
* is useful if you need to free the memory allocated for the original key,
* for example before calling g_hash_table_remove().
*
* Return value: #TRUE if the key was found in the #GHashTable.
**/
gboolean
g_hash_table_lookup_extended (GHashTable *hash_table,
gconstpointer lookup_key,
gpointer *orig_key,
gpointer *value)
{
GHashNode *node;
g_return_val_if_fail (hash_table != NULL, FALSE);
node = *g_hash_table_lookup_node (hash_table, lookup_key);
if (node)
{
if (orig_key)
*orig_key = node->key;
if (value)
*value = node->value;
return TRUE;
}
else
return FALSE;
}
/**
* g_hash_table_insert:
* @hash_table: a #GHashTable.
* @key: a key to insert.
* @value: the value to associate with the key.
*
* Inserts a new key and value into a #GHashTable.
*
* If the key already exists in the #GHashTable its current value is replaced
* with the new value. If you supplied a value_destroy_func when creating the
* #GHashTable, the old value is freed using that function. If you supplied
* a key_destroy_func when creating the #GHashTable, the passed key is freed
* using that function.
**/
void
g_hash_table_insert (GHashTable *hash_table,
gpointer key,
gpointer value)
{
GHashNode **node;
g_return_if_fail (hash_table != NULL);
node = g_hash_table_lookup_node (hash_table, key);
if (*node)
{
/* do not reset node->key in this place, keeping
* the old key is the intended behaviour.
* g_hash_table_replace() can be used instead.
*/
/* free the passed key */
if (hash_table->key_destroy_func)
hash_table->key_destroy_func (key);
if (hash_table->value_destroy_func)
hash_table->value_destroy_func ((*node)->value);
(*node)->value = value;
}
else
{
*node = g_hash_node_new (key, value);
hash_table->nnodes++;
g_hash_table_resize (hash_table);
}
}
/**
* g_hash_table_replace:
* @hash_table: a #GHashTable.
* @key: a key to insert.
* @value: the value to associate with the key.
*
* Inserts a new key and value into a #GHashTable similar to
* g_hash_table_insert(). The difference is that if the key already exists
* in the #GHashTable, it gets replaced by the new key. If you supplied a
* value_destroy_func when creating the #GHashTable, the old value is freed
* using that function. If you supplied a key_destroy_func when creating the
* #GHashTable, the old key is freed using that function.
**/
void
g_hash_table_replace (GHashTable *hash_table,
gpointer key,
gpointer value)
{
GHashNode **node;
g_return_if_fail (hash_table != NULL);
node = g_hash_table_lookup_node (hash_table, key);
if (*node)
{
if (hash_table->key_destroy_func)
hash_table->key_destroy_func ((*node)->key);
if (hash_table->value_destroy_func)
hash_table->value_destroy_func ((*node)->value);
(*node)->key = key;
(*node)->value = value;
}
else
{
*node = g_hash_node_new (key, value);
hash_table->nnodes++;
g_hash_table_resize (hash_table);
}
}
/**
* g_hash_table_remove:
* @hash_table: a #GHashTable.
* @key: the key to remove.
*
* Removes a key and its associated value from a #GHashTable.
*
* If the #GHashTable was created using g_hash_table_new_full(), the
* key and value are freed using the supplied destroy_functions, otherwise
* you have to make sure that any dynamically allocated values are freed
* yourself.
*
* Return value: #TRUE if the key was found and removed from the #GHashTable.
**/
gboolean
g_hash_table_remove (GHashTable *hash_table,
gconstpointer key)
{
GHashNode **node, *dest;
g_return_val_if_fail (hash_table != NULL, FALSE);
node = g_hash_table_lookup_node (hash_table, key);
if (*node)
{
dest = *node;
(*node) = dest->next;
g_hash_node_destroy (dest,
hash_table->key_destroy_func,
hash_table->value_destroy_func);
hash_table->nnodes--;
g_hash_table_resize (hash_table);
return TRUE;
}
return FALSE;
}
/**
* g_hash_table_steal:
* @hash_table: a #GHashTable.
* @key: the key to remove.
*
* Removes a key and its associated value from a #GHashTable without
* calling the key and value destroy functions.
*
* Return value: #TRUE if the key was found and removed from the #GHashTable.
**/
gboolean
g_hash_table_steal (GHashTable *hash_table,
gconstpointer key)
{
GHashNode **node, *dest;
g_return_val_if_fail (hash_table != NULL, FALSE);
node = g_hash_table_lookup_node (hash_table, key);
if (*node)
{
dest = *node;
(*node) = dest->next;
g_hash_node_destroy (dest, NULL, NULL);
hash_table->nnodes--;
g_hash_table_resize (hash_table);
return TRUE;
}
return FALSE;
}
/**
* g_hash_table_foreach_remove:
* @hash_table: a #GHashTable.
* @func: the function to call for each key/value pair.
* @user_data: user data to pass to the function.
*
* Calls the given function for each key/value pair in the #GHashTable.
* If the function returns TRUE, then the key/value pair is removed from the
* #GHashTable. If you supplied key or value destroy functions when creating
* the #GHashTable, they are used to free the memory allocated for the removed
* keys and values.
*
* Return value: the number of key/value pairs removed.
**/
guint
g_hash_table_foreach_remove (GHashTable *hash_table,
GHRFunc func,
gpointer user_data)
{
g_return_val_if_fail (hash_table != NULL, 0);
g_return_val_if_fail (func != NULL, 0);
return g_hash_table_foreach_remove_or_steal (hash_table, func, user_data, TRUE);
}
/**
* g_hash_table_foreach_steal:
* @hash_table: a #GHashTable.
* @func: the function to call for each key/value pair.
* @user_data: user data to pass to the function.
*
* Calls the given function for each key/value pair in the #GHashTable.
* If the function returns TRUE, then the key/value pair is removed from the
* #GHashTable, but no key or value destroy functions are called.
*
* Return value: the number of key/value pairs removed.
**/
guint
g_hash_table_foreach_steal (GHashTable *hash_table,
GHRFunc func,
gpointer user_data)
{
g_return_val_if_fail (hash_table != NULL, 0);
g_return_val_if_fail (func != NULL, 0);
return g_hash_table_foreach_remove_or_steal (hash_table, func, user_data, FALSE);
}
static guint
g_hash_table_foreach_remove_or_steal (GHashTable *hash_table,
GHRFunc func,
gpointer user_data,
gboolean notify)
{
GHashNode *node, *prev;
guint i;
guint deleted = 0;
for (i = 0; i < hash_table->size; i++)
{
restart:
prev = NULL;
for (node = hash_table->nodes[i]; node; prev = node, node = node->next)
{
if ((* func) (node->key, node->value, user_data))
{
deleted += 1;
hash_table->nnodes -= 1;
if (prev)
{
prev->next = node->next;
g_hash_node_destroy (node,
notify ? hash_table->value_destroy_func : NULL,
notify ? hash_table->key_destroy_func : NULL);
node = prev;
}
else
{
hash_table->nodes[i] = node->next;
g_hash_node_destroy (node,
notify ? hash_table->value_destroy_func : NULL,
notify ? hash_table->key_destroy_func : NULL);
goto restart;
}
}
}
}
g_hash_table_resize (hash_table);
return deleted;
}
/**
* g_hash_table_foreach:
* @hash_table: a #GHashTable.
* @func: the function to call for each key/value pair.
* @user_data: user data to pass to the function.
*
* Calls the given function for each of the key/value pairs in the #GHashTable.
* The function is passed the key and value of each pair, and the given
* @user_data parameter.
**/
void
g_hash_table_foreach (GHashTable *hash_table,
GHFunc func,
gpointer user_data)
{
GHashNode *node;
gint i;
g_return_if_fail (hash_table != NULL);
g_return_if_fail (func != NULL);
for (i = 0; i < hash_table->size; i++)
for (node = hash_table->nodes[i]; node; node = node->next)
(* func) (node->key, node->value, user_data);
}
/**
* g_hash_table_size:
* @hash_table: a #GHashTable.
*
* Returns the number of elements contained in the #GHashTable.
*
* Return value: the number of key/value pairs in the #GHashTable.
**/
guint
g_hash_table_size (GHashTable *hash_table)
{
g_return_val_if_fail (hash_table != NULL, 0);
return hash_table->nnodes;
}
/**
* g_hash_table_freeze:
* @hash_table: a #GHashTable.
*
* This function is deprecated and will be removed in the next major
* release of GLib. It does nothing.
**/
void
g_hash_table_freeze (GHashTable *hash_table)
{
#ifdef G_ENABLE_DEBUG
static gboolean first_call = TRUE;
if (first_call)
{
g_warning("g_hash_table_freeze and g_hash_table_thaw are deprecated.");
first_call = FALSE;
}
#endif /* G_ENABLE_DEBUG */
}
/**
* g_hash_table_thaw:
* @hash_table: a #GHashTable.
*
* This function is deprecated and will be removed in the next major
* release of GLib. It does nothing.
**/
void
g_hash_table_thaw (GHashTable *hash_table)
{
}
static void
g_hash_table_resize (GHashTable *hash_table)
{
GHashNode **new_nodes;
GHashNode *node;
GHashNode *next;
gfloat nodes_per_list;
guint hash_val;
gint new_size;
gint i;
nodes_per_list = (gfloat) hash_table->nnodes / (gfloat) hash_table->size;
if ((nodes_per_list > 0.3 || hash_table->size <= HASH_TABLE_MIN_SIZE) &&
(nodes_per_list < 3.0 || hash_table->size >= HASH_TABLE_MAX_SIZE))
return;
new_size = CLAMP(g_spaced_primes_closest (hash_table->nnodes),
HASH_TABLE_MIN_SIZE,
HASH_TABLE_MAX_SIZE);
new_nodes = g_new0 (GHashNode*, new_size);
for (i = 0; i < hash_table->size; i++)
for (node = hash_table->nodes[i]; node; node = next)
{
next = node->next;
hash_val = (* hash_table->hash_func) (node->key) % new_size;
node->next = new_nodes[hash_val];
new_nodes[hash_val] = node;
}
g_free (hash_table->nodes);
hash_table->nodes = new_nodes;
hash_table->size = new_size;
}
static GHashNode*
g_hash_node_new (gpointer key,
gpointer value)
{
GHashNode *hash_node;
G_LOCK (g_hash_global);
if (node_free_list)
{
hash_node = node_free_list;
node_free_list = node_free_list->next;
}
else
{
if (!node_mem_chunk)
node_mem_chunk = g_mem_chunk_new ("hash node mem chunk",
sizeof (GHashNode),
1024, G_ALLOC_ONLY);
hash_node = g_chunk_new (GHashNode, node_mem_chunk);
}
G_UNLOCK (g_hash_global);
hash_node->key = key;
hash_node->value = value;
hash_node->next = NULL;
return hash_node;
}
static void
g_hash_node_destroy (GHashNode *hash_node,
GDestroyNotify key_destroy_func,
GDestroyNotify value_destroy_func)
{
if (key_destroy_func)
key_destroy_func (hash_node->key);
if (value_destroy_func)
value_destroy_func (hash_node->value);
#ifdef ENABLE_GC_FRIENDLY
hash_node->key = NULL;
hash_node->value = NULL;
#endif /* ENABLE_GC_FRIENDLY */
G_LOCK (g_hash_global);
hash_node->next = node_free_list;
node_free_list = hash_node;
G_UNLOCK (g_hash_global);
}
static void
g_hash_nodes_destroy (GHashNode *hash_node,
GFreeFunc key_destroy_func,
GFreeFunc value_destroy_func)
{
if (hash_node)
{
GHashNode *node = hash_node;
while (node->next)
{
if (key_destroy_func)
key_destroy_func (node->key);
if (value_destroy_func)
value_destroy_func (node->value);
#ifdef ENABLE_GC_FRIENDLY
node->key = NULL;
node->value = NULL;
#endif /* ENABLE_GC_FRIENDLY */
node = node->next;
}
if (key_destroy_func)
key_destroy_func (node->key);
if (value_destroy_func)
value_destroy_func (node->value);
#ifdef ENABLE_GC_FRIENDLY
node->key = NULL;
node->value = NULL;
#endif /* ENABLE_GC_FRIENDLY */
G_LOCK (g_hash_global);
node->next = node_free_list;
node_free_list = hash_node;
G_UNLOCK (g_hash_global);
}
}