From 7a0cd6793e33a04187c2a6eafa6eaf8aea32b938 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?kleines=20Filmr=C3=B6llchen?= <filmroellchen@serenityos.org>
Date: Sun, 3 Apr 2022 17:41:21 +0200
Subject: [PATCH] AK: Add non-const iterator for CircularQueue

---
 AK/CircularQueue.h | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/AK/CircularQueue.h b/AK/CircularQueue.h
index d4ab79d9b3f..979989aa2fd 100644
--- a/AK/CircularQueue.h
+++ b/AK/CircularQueue.h
@@ -64,6 +64,7 @@ public:
     }
 
     const T& at(size_t index) const { return elements()[(m_head + index) % Capacity]; }
+    T& at(size_t index) { return elements()[(m_head + index) % Capacity]; }
 
     const T& first() const { return at(0); }
     const T& last() const { return at(size() - 1); }
@@ -90,9 +91,34 @@ public:
         size_t m_index { 0 };
     };
 
+    class Iterator {
+    public:
+        bool operator!=(Iterator const& other) { return m_index != other.m_index; }
+        Iterator& operator++()
+        {
+            ++m_index;
+            return *this;
+        }
+
+        T& operator*() const { return m_queue.at(m_index); }
+
+    private:
+        friend class CircularQueue;
+        Iterator(CircularQueue& queue, size_t const index)
+            : m_queue(queue)
+            , m_index(index)
+        {
+        }
+        CircularQueue& m_queue;
+        size_t m_index { 0 };
+    };
+
     ConstIterator begin() const { return ConstIterator(*this, 0); }
     ConstIterator end() const { return ConstIterator(*this, size()); }
 
+    Iterator begin() { return Iterator(*this, 0); }
+    Iterator end() { return Iterator(*this, size()); }
+
     size_t head_index() const { return m_head; }
 
 protected: