From 7592f9afd5bf1b794c125db14762707f969c0635 Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Thu, 20 Feb 2020 13:18:42 +0100
Subject: [PATCH] AK: Use size_t for CircularQueue and CircularDeque

---
 AK/CircularDeque.h                         |  2 +-
 AK/CircularQueue.h                         | 20 ++++++++++----------
 AK/Forward.h                               |  6 ++++--
 Applications/SystemMonitor/GraphWidget.cpp |  2 +-
 Kernel/TTY/TTY.cpp                         |  4 +++-
 5 files changed, 19 insertions(+), 15 deletions(-)

diff --git a/AK/CircularDeque.h b/AK/CircularDeque.h
index 319106e249d..445abe46aaa 100644
--- a/AK/CircularDeque.h
+++ b/AK/CircularDeque.h
@@ -32,7 +32,7 @@
 
 namespace AK {
 
-template<typename T, int Capacity>
+template<typename T, size_t Capacity>
 class CircularDeque : public CircularQueue<T, Capacity> {
 public:
     T dequeue_end()
diff --git a/AK/CircularQueue.h b/AK/CircularQueue.h
index 2941958bdec..69f641aa28f 100644
--- a/AK/CircularQueue.h
+++ b/AK/CircularQueue.h
@@ -32,7 +32,7 @@
 
 namespace AK {
 
-template<typename T, int Capacity>
+template<typename T, size_t Capacity>
 class CircularQueue {
 public:
     CircularQueue()
@@ -46,7 +46,7 @@ public:
 
     void clear()
     {
-        for (int i = 0; i < m_size; ++i)
+        for (size_t i = 0; i < m_size; ++i)
             elements()[(m_head + i) % Capacity].~T();
 
         m_head = 0;
@@ -54,9 +54,9 @@ public:
     }
 
     bool is_empty() const { return !m_size; }
-    int size() const { return m_size; }
+    size_t size() const { return m_size; }
 
-    int capacity() const { return Capacity; }
+    size_t capacity() const { return Capacity; }
 
     void enqueue(T&& value)
     {
@@ -87,7 +87,7 @@ public:
         return value;
     }
 
-    const T& at(int index) const { return elements()[(m_head + index) % Capacity]; }
+    const T& at(size_t index) const { return elements()[(m_head + index) % Capacity]; }
 
     const T& first() const { return at(0); }
     const T& last() const { return at(size() - 1); }
@@ -107,19 +107,19 @@ public:
 
     private:
         friend class CircularQueue;
-        ConstIterator(const CircularQueue& queue, const int index)
+        ConstIterator(const CircularQueue& queue, const size_t index)
             : m_queue(queue)
             , m_index(index)
         {
         }
         const CircularQueue& m_queue;
-        int m_index { 0 };
+        size_t m_index { 0 };
     };
 
     ConstIterator begin() const { return ConstIterator(*this, m_head); }
     ConstIterator end() const { return ConstIterator(*this, size()); }
 
-    int head_index() const { return m_head; }
+    size_t head_index() const { return m_head; }
 
 protected:
     T* elements() { return reinterpret_cast<T*>(m_storage); }
@@ -127,8 +127,8 @@ protected:
 
     friend class ConstIterator;
     alignas(T) u8 m_storage[sizeof(T) * Capacity];
-    int m_size { 0 };
-    int m_head { 0 };
+    size_t m_size { 0 };
+    size_t m_head { 0 };
 };
 
 }
diff --git a/AK/Forward.h b/AK/Forward.h
index ae6758b41b3..f69794d860a 100644
--- a/AK/Forward.h
+++ b/AK/Forward.h
@@ -26,6 +26,8 @@
 
 #pragma once
 
+#include <AK/Types.h>
+
 namespace AK {
 
 class Bitmap;
@@ -57,7 +59,7 @@ class DoublyLinkedList;
 template<typename T>
 class InlineLinkedList;
 
-template<typename T, int capacity>
+template<typename T, size_t capacity>
 class CircularQueue;
 
 template<typename T>
@@ -116,8 +118,8 @@ using AK::FixedArray;
 using AK::Function;
 using AK::HashMap;
 using AK::HashTable;
-using AK::IPv4Address;
 using AK::InlineLinkedList;
+using AK::IPv4Address;
 using AK::JsonArray;
 using AK::JsonObject;
 using AK::JsonValue;
diff --git a/Applications/SystemMonitor/GraphWidget.cpp b/Applications/SystemMonitor/GraphWidget.cpp
index 9023b55768a..70d6175b7ea 100644
--- a/Applications/SystemMonitor/GraphWidget.cpp
+++ b/Applications/SystemMonitor/GraphWidget.cpp
@@ -58,7 +58,7 @@ void GraphWidget::paint_event(GUI::PaintEvent& event)
     float scale = (float)inner_rect.height() / (float)m_max;
 
     Gfx::Point prev_point;
-    for (int i = 0; i < m_values.size(); ++i) {
+    for (size_t i = 0; i < m_values.size(); ++i) {
         int x = inner_rect.right() - (i * 2) + 1;
         if (x < 0)
             break;
diff --git a/Kernel/TTY/TTY.cpp b/Kernel/TTY/TTY.cpp
index 8a092579712..debf0f6a6e4 100644
--- a/Kernel/TTY/TTY.cpp
+++ b/Kernel/TTY/TTY.cpp
@@ -54,7 +54,9 @@ void TTY::set_default_termios()
 
 ssize_t TTY::read(FileDescription&, u8* buffer, ssize_t size)
 {
-    if (m_input_buffer.size() < size)
+    ASSERT(size >= 0);
+
+    if (m_input_buffer.size() < static_cast<size_t>(size))
         size = m_input_buffer.size();
 
     if (in_canonical_mode()) {