telepathygabble/src/gintset.c
changeset 0 d0f3a028347a
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/telepathygabble/src/gintset.c	Tue Feb 02 01:10:06 2010 +0200
@@ -0,0 +1,450 @@
+/* gintset.c - Source for a Glib-link set of integers
+ * Copyright (C) 2006 Collabora Ltd.
+ * 
+ * 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 2.1 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., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#include <string.h>
+#include <glib.h>
+#include "gintset.h"
+
+#define DEFAULT_SIZE 16
+#define DEFAULT_INCREMENT 8
+#define DEFAULT_INCREMENT_LOG2 3
+
+struct _GIntSet
+{
+  guint32 *bits;
+  guint size;
+};
+
+static GIntSet *
+_g_intset_new_with_size (guint size)
+{
+  GIntSet *set = g_new (GIntSet, 1);
+  set->size = MAX (size, DEFAULT_SIZE);
+  set->bits = g_new0 (guint32, set->size);
+  return set;
+}
+
+
+GIntSet *
+g_intset_new ()
+{
+  return _g_intset_new_with_size (DEFAULT_SIZE);
+}
+
+/**
+ * g_intset_destroy:
+ * @set: set
+ *
+ * delete the set
+ */
+
+void
+g_intset_destroy (GIntSet *set)
+{
+  g_return_if_fail (set != NULL);
+
+  g_free (set->bits);
+  g_free (set);
+}
+
+/**
+ * g_intset_clear:
+ * @set : set
+ *
+ * Unset every integer in the set.
+ */
+void
+g_intset_clear (GIntSet *set)
+{
+  g_return_if_fail (set != NULL);
+
+  memset (set->bits, 0, set->size * sizeof (guint32));
+}
+
+/**
+ * g_intset_add:
+ * @set: set
+ * @element: integer to add
+ *
+ * Add an integer into a GIntSet
+ */
+
+void
+g_intset_add (GIntSet *set, guint element)
+{
+  guint offset;
+  guint newsize;
+
+  g_return_if_fail (set != NULL);
+
+  offset = element >> 5;
+
+  if (offset >= set->size)
+  {
+    newsize = ((offset>>DEFAULT_INCREMENT_LOG2) +1 ) << DEFAULT_INCREMENT_LOG2;
+    set->bits = g_renew(guint32, set->bits, newsize);
+    memset (set->bits + set->size, 0, sizeof(guint32) * (newsize - set->size));
+    set->size = newsize;
+    g_assert(offset<newsize);
+  }
+  set->bits[offset] = set->bits[offset] | (1<<(element & 0x1f));
+}
+
+/**
+ * g_intset_remove:
+ * @set: set
+ * @element: integer to add
+ *
+ * Remove an integer from a GIntSet
+ * Returns: TRUE if element was in set
+ */
+ 
+gboolean
+g_intset_remove (GIntSet *set, guint element)
+{
+  guint offset;
+  guint mask;
+
+  g_return_val_if_fail (set != NULL, FALSE);
+
+  offset = element >> 5;
+  mask = 1 << (element & 0x1f);
+  if (offset >= set->size)
+    return FALSE;
+  else if (!(set->bits[offset] & mask))
+    return FALSE;
+  else
+    {
+      set->bits[offset] &= ~mask;
+      return TRUE;
+    }
+}
+
+/**
+ * g_intset_is_member:
+ * @set: set
+ * @element: integer to test
+ *
+ * Tests if @element is a member of @set
+ * Returns: TRUE if element was in set
+ */
+ 
+gboolean
+g_intset_is_member (const GIntSet *set, guint element)
+{
+  guint offset;
+
+  g_return_val_if_fail (set != NULL, FALSE);
+
+  offset = element >> 5;
+  if (offset >= set->size)
+    return FALSE;
+  else
+    return (set->bits[offset] & (1 << (element & 0x1f)));
+}
+
+/**
+ * g_intset_foreach:
+ * @set: set
+ * @func: @GIntFunc to use to iterate the set
+ * @userdata: user data to pass to each call of @func
+ *
+ * Iterates every member of the set calling @func
+ */
+
+void
+g_intset_foreach (const GIntSet *set, GIntFunc func, gpointer userdata)
+{
+  guint i, j;
+
+  g_return_if_fail (set != NULL);
+  g_return_if_fail (func != NULL);
+
+  for (i = 0; i < set->size; i++)
+    {
+      if (set->bits[i])
+        for (j = 0; j < 32; j++)
+          {
+            if (set->bits[i] & 1 << j)
+              func (i * 32 + j, userdata);
+          }
+    }
+}
+
+
+static void
+addint (guint32 i, gpointer data)
+{
+  GArray *array = (GArray *) data;
+  g_array_append_val (array, i);
+}
+
+/**
+ * g_intset_to_array:
+ * @set: set to convert
+ * Convert a gintset to an array, allocates the array for you, hence you
+ * must free it after use.
+ */
+
+GArray *
+g_intset_to_array (GIntSet *set)
+{
+  GArray *array;
+
+  g_return_val_if_fail (set != NULL, NULL);
+
+  array = g_array_new (FALSE, TRUE, sizeof (guint32));
+
+  g_intset_foreach (set, addint, array);
+
+  return array;
+}
+
+
+GIntSet *
+g_intset_from_array (GArray *array)
+{
+  GIntSet *set;
+  guint32 max, i;
+
+  g_return_val_if_fail (array != NULL, NULL);
+
+  /* look at the 1st, last and middle values in the array to get an
+   * approximation of the largest */
+  max = 0;
+  if (array->len > 0)
+    max = g_array_index (array, guint32, 0);
+  if (array->len > 1)
+    max = MAX (max, g_array_index (array, guint32, array->len - 1));
+  if (array->len > 2)
+    max = MAX (max, g_array_index (array, guint32, (array->len - 1) >> 1));
+  set = _g_intset_new_with_size (1 + (max >> 5));
+
+  for (i = 0; i < array->len; i++)
+    {
+      g_intset_add (set, g_array_index (array, guint32, i));
+    }
+
+  return set;
+}
+
+
+guint
+g_intset_size (const GIntSet *set)
+{
+  guint i, count = 0;
+  guint32 n;
+
+  g_return_val_if_fail (set != NULL, 0);
+
+  for (i = 0; i < set->size; i++)
+    {
+      n = set->bits[i];
+      n = n - ((n >> 1) & 033333333333) - ((n >> 2) & 011111111111);
+      count += ((n + (n >> 3)) & 030707070707) % 63;
+    }
+
+  return count;
+}
+
+
+gboolean
+g_intset_is_equal (const GIntSet *left, const GIntSet *right)
+{
+  const GIntSet *large, *small;
+  guint i;
+
+  g_return_val_if_fail (left != NULL, FALSE);
+  g_return_val_if_fail (right != NULL, FALSE);
+
+  if (left->size > right->size)
+    {
+      large = left;
+      small = right;
+    }
+  else
+    {
+      large = right;
+      small = left;
+    }
+
+  for (i = 0; i < small->size; i++)
+    {
+      if (large->bits[i] != small->bits[i])
+        return FALSE;
+    }
+
+  for (i = small->size; i < large->size; i++)
+    {
+      if (large->bits[i] != 0)
+        return FALSE;
+    }
+
+  return TRUE;
+}
+
+GIntSet *
+g_intset_copy (const GIntSet *orig)
+{
+  GIntSet *ret;
+
+  g_return_val_if_fail (orig != NULL, NULL);
+
+  ret = _g_intset_new_with_size (orig->size);
+  memcpy (ret->bits, orig->bits, (ret->size * sizeof (guint32)));
+
+  return ret;
+}
+
+
+GIntSet *
+g_intset_intersection (const GIntSet *left, const GIntSet *right)
+{
+  const GIntSet *large, *small;
+  GIntSet *ret;
+  guint i;
+
+  g_return_val_if_fail (left != NULL, NULL);
+  g_return_val_if_fail (right != NULL, NULL);
+
+  if (left->size > right->size)
+    {
+      large = left;
+      small = right;
+    }
+  else
+    {
+      large = right;
+      small = left;
+    }
+
+  ret = g_intset_copy (small);
+
+  for (i = 0; i < ret->size; i++)
+    {
+      ret->bits[i] &= large->bits[i];
+    }
+
+  return ret;
+}
+
+
+GIntSet *
+g_intset_union (const GIntSet *left, const GIntSet *right)
+{
+  const GIntSet *large, *small;
+  GIntSet *ret;
+  guint i;
+
+  g_return_val_if_fail (left != NULL, NULL);
+  g_return_val_if_fail (right != NULL, NULL);
+
+  if (left->size > right->size)
+    {
+      large = left;
+      small = right;
+    }
+  else
+    {
+      large = right;
+      small = left;
+    }
+
+  ret = g_intset_copy (large);
+
+  for (i = 0; i < small->size; i++)
+    {
+      ret->bits[i] |= small->bits[i];
+    }
+
+  return ret;
+}
+
+
+GIntSet *
+g_intset_difference (const GIntSet *left, const GIntSet *right)
+{
+  GIntSet *ret;
+  guint i;
+
+  g_return_val_if_fail (left != NULL, NULL);
+  g_return_val_if_fail (right != NULL, NULL);
+
+  ret = g_intset_copy (left);
+
+  for (i = 0; i < MIN (right->size, left->size); i++)
+    {
+      ret->bits[i] &= ~right->bits[i];
+    }
+
+  return ret;
+}
+
+
+GIntSet *
+g_intset_symmetric_difference (const GIntSet *left, const GIntSet *right)
+{
+  const GIntSet *large, *small;
+  GIntSet *ret;
+  guint i;
+
+  g_return_val_if_fail (left != NULL, NULL);
+  g_return_val_if_fail (right != NULL, NULL);
+
+  if (left->size > right->size)
+    {
+      large = left;
+      small = right;
+    }
+  else
+    {
+      large = right;
+      small = left;
+    }
+
+  ret = g_intset_copy (large);
+
+  for (i = 0; i < small->size; i++)
+    {
+      ret->bits[i] ^= small->bits[i];
+    }
+
+  return ret;
+}
+
+static void
+_dump_foreach (guint i, gpointer data)
+{
+   GString *tmp = (GString *) data;
+
+  if (tmp->len == 0)
+    g_string_append_printf (tmp, "%d", i);
+  else
+    g_string_append_printf (tmp, " %d", i);
+}
+
+gchar *
+g_intset_dump (const GIntSet *set)
+{
+  GString *tmp = g_string_new ("");
+
+  g_intset_foreach (set, _dump_foreach, tmp);
+  return g_string_free (tmp, FALSE);
+}