[gtk/selection-filter: 1/2] bitset: Add APIs needed for a filterlistmodel

[Matthias Clasen <matthiasc src gnome org>]

commit 09666368036df6afe49ec0dc3b71202417263997
Author: Benjamin Otte <otte redhat com>
Date:   Mon Jun 29 19:04:07 2020 +0200

    bitset: Add APIs needed for a filterlistmodel

 docs/reference/gtk/gtk4-sections.txt |  3 ++
 gtk/gtkbitset.c                      | 70 ++++++++++++++++++++++++++++++++++++
 gtk/gtkbitset.h                      |  9 +++++
 3 files changed, 82 insertions(+)
---
diff --git a/docs/reference/gtk/gtk4-sections.txt b/docs/reference/gtk/gtk4-sections.txt
index 5fefc4d1da..8ec00d44e6 100644
--- a/docs/reference/gtk/gtk4-sections.txt
+++ b/docs/reference/gtk/gtk4-sections.txt
@@ -355,6 +355,9 @@ gtk_bitset_is_empty
 gtk_bitset_equals
 gtk_bitset_get_minimum
 gtk_bitset_get_maximum
+gtk_bitset_get_size
+gtk_bitset_get_size_in_range
+gtk_bitset_get_nth
 <SUBSECTION>
 gtk_bitset_remove_all
 gtk_bitset_add
diff --git a/gtk/gtkbitset.c b/gtk/gtkbitset.c
index f2cf9ff446..c69efd0cf7 100644
--- a/gtk/gtkbitset.c
+++ b/gtk/gtkbitset.c
@@ -193,6 +193,76 @@ gtk_bitset_get_maximum (const GtkBitset *self)
   return roaring_bitmap_maximum (&self->roaring);
 }
 
+/**
+ * gtk_bitset_get_size:
+ * @self: a #GtkBitSet
+ *
+ * Gets the number of values that were added to the set.  
+ * For example, if the set is empty, 0 is returned.
+ *
+ * Note that this function returns a #guint64, because when all values are
+ * set, the return value is #G_MAXUINT + 1. Unless you are sure this cannot
+ * happen (it can't with #GListModel), be sure to use a 64bit type.
+ *
+ * Returns: The number of values in the set.
+ **/
+guint64
+gtk_bitset_get_size (const GtkBitset *self)
+{
+  g_return_val_if_fail (self != NULL, 0);
+
+  return roaring_bitmap_get_cardinality (&self->roaring);
+}
+
+/**
+ * gtk_bitset_get_size_in_range:
+ * @self: a #GtkBitSet
+ * @first: the first element to include
+ * @last: the last element to include
+ *
+ * Gets the number of values that are part of the set from @first to @last
+ * (inclusive).
+ *
+ * Note that this function returns a #guint64, because when all values are
+ * set, the return value is #G_MAXUINT + 1. Unless you are sure this cannot
+ * happen (it can't with #GListModel), be sure to use a 64bit type.
+ *
+ * Returns: The number of values in the set from @first to @last.
+ **/
+guint64
+gtk_bitset_get_size_in_range (const GtkBitset *self,
+                              guint            first,
+                              guint            last)
+{
+  g_return_val_if_fail (self != NULL, 0);
+  g_return_val_if_fail (last >= first, 0);
+
+  return roaring_bitmap_range_cardinality (&self->roaring, first, ((uint64_t) last) + 1);
+}
+
+/**
+ * gtk_bitset_get_nth:
+ * @self: a #GtkBitset
+ * @nth: index of the item to get
+ *
+ * Returns the value of the @nth item in self.
+ *
+ * If @nth is >= the size of @self, 0 is returned.
+ *
+ * Returns: the value of the @nth item in @self
+ **/
+guint
+gtk_bitset_get_nth (const GtkBitset *self,
+                    guint            nth)
+{
+  uint32_t result;
+
+  if (!roaring_bitmap_select (&self->roaring, nth, &result))
+    return 0;
+
+  return result;
+}
+
 /**
  * gtk_bitset_new_empty:
  *
diff --git a/gtk/gtkbitset.h b/gtk/gtkbitset.h
index fc26e0d7de..1fcbf6faeb 100644
--- a/gtk/gtkbitset.h
+++ b/gtk/gtkbitset.h
@@ -48,6 +48,15 @@ GDK_AVAILABLE_IN_ALL
 gboolean                gtk_bitset_equals                       (const GtkBitset        *self,
                                                                  const GtkBitset        *other);
 GDK_AVAILABLE_IN_ALL
+guint64                 gtk_bitset_get_size                     (const GtkBitset        *self);
+GDK_AVAILABLE_IN_ALL
+guint64                 gtk_bitset_get_size_in_range            (const GtkBitset        *self,
+                                                                 guint                   first,
+                                                                 guint                   last);
+GDK_AVAILABLE_IN_ALL
+guint                   gtk_bitset_get_nth                      (const GtkBitset        *self,
+                                                                 guint                   nth);
+GDK_AVAILABLE_IN_ALL
 guint                   gtk_bitset_get_minimum                  (const GtkBitset        *self);
 GDK_AVAILABLE_IN_ALL
 guint                   gtk_bitset_get_maximum                  (const GtkBitset        *self);