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-rw-r--r--flow/gsl/gslglibhash.cc151
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diff --git a/flow/gsl/gslglibhash.cc b/flow/gsl/gslglibhash.cc
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+/* GSL Glib Hashtable implementation
+ * Copyright (C) 2001 Stefan Westerfeld
+ *
+ * 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.
+ */
+#include "gslglib.h"
+#include <list>
+#include <map>
+
+using std::list;
+using std::pair;
+using std::map;
+
+/*
+ * this uses a map of list to emulate somewhat hashtable like behaviour - note
+ * that insert and remove are O(log N) due to the use of a map, instead of
+ * ~ O(1) which they would be for a "real" hashtable
+ */
+struct _GHashTable
+{
+ GHashFunc hashFunc;
+ GEqualFunc equalFunc;
+ map<guint /*hashvalue for key*/, list< pair<gpointer,gpointer> > /*(key,value) pairs*/> nodes;
+
+ /*Con*/ _GHashTable (GHashFunc hf, GEqualFunc ef) :
+ hashFunc(hf), equalFunc(ef) { }
+};
+
+
+GHashTable* g_hash_table_new (GHashFunc hash_func,
+ GEqualFunc key_equal_func)
+{
+ return new GHashTable (hash_func?hash_func:g_direct_hash, key_equal_func?key_equal_func:g_direct_equal);
+}
+void g_hash_table_destroy (GHashTable *hash_table)
+{
+ g_return_if_fail (hash_table != NULL);
+
+ delete hash_table;
+}
+void g_hash_table_insert (GHashTable *hash_table,
+ gpointer key,
+ gpointer value)
+{
+ g_return_if_fail (hash_table != NULL);
+ guint hashvalue = hash_table->hashFunc (key);
+
+ list< pair<gpointer,gpointer> >& bucket = hash_table->nodes[hashvalue];
+ list< pair<gpointer,gpointer> >::iterator i;
+
+ for (i = bucket.begin(); i != bucket.end(); i++)
+ {
+ if (hash_table->equalFunc(i->first, key))
+ {
+ if (value || TRUE)
+ {
+ i->second = value; /* overwrite old hash value */
+ return;
+ }
+ else
+ {
+ bucket.erase(i); /* remove value */
+
+ if (bucket.empty()) /* remove bucket if this was the only value */
+ hash_table->nodes.erase (hashvalue);
+ return;
+ }
+ }
+ }
+
+ if (value)
+ hash_table->nodes[hashvalue].push_back(std::make_pair (key, value));
+}
+
+gpointer g_hash_table_lookup (GHashTable *hash_table,
+ gconstpointer key)
+{
+ g_return_val_if_fail (hash_table != NULL, NULL);
+
+ guint hashvalue = hash_table->hashFunc (key);
+
+ list< pair<gpointer,gpointer> >& bucket = hash_table->nodes[hashvalue];
+ list< pair<gpointer,gpointer> >::iterator i;
+
+ for (i = bucket.begin(); i != bucket.end(); i++)
+ {
+ if (hash_table->equalFunc(i->first, key))
+ return i->second;
+ }
+
+ return 0;
+}
+gboolean g_hash_table_remove (GHashTable *hash_table,
+ gconstpointer key)
+{
+ g_return_val_if_fail (hash_table != NULL, FALSE);
+
+ guint hashvalue = hash_table->hashFunc (key);
+
+ list< pair<gpointer,gpointer> >& bucket = hash_table->nodes[hashvalue];
+ list< pair<gpointer,gpointer> >::iterator i;
+
+ for (i = bucket.begin(); i != bucket.end(); i++)
+ {
+ if (hash_table->equalFunc(i->first, key))
+ {
+ bucket.erase (i);
+
+ if (bucket.empty()) /* remove bucket if this was the only value */
+ hash_table->nodes.erase (hashvalue);
+ return true;
+ }
+ }
+
+ return false;
+}
+
+void g_hash_table_foreach (GHashTable *hash_table,
+ GHFunc func,
+ gpointer user_data)
+{
+ map<guint, list< pair<gpointer,gpointer> > >::iterator bi;
+
+ g_return_if_fail (hash_table != NULL);
+
+ /* for all buckets */
+ for (bi = hash_table->nodes.begin (); bi != hash_table->nodes.end (); bi++)
+ {
+ list< pair<gpointer,gpointer> >& bucket = bi->second;
+ list< pair<gpointer,gpointer> >::iterator i;
+
+ /* for each element in the current bucket */
+ for (i = bucket.begin(); i != bucket.end(); i++)
+ func ((void*) i->first, (void*) i->second, user_data);
+ }
+}
+
+/* vim:set ts=8 sw=2 sts=2: */