LibIPC: Move AutoCloseFileDescriptor to its own header

Author: https://github.com/stasoid
Commit: ccf303eefc
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/5010
Reviewed-by: https://github.com/ADKaster ✅

Libraries/LibIPC/AutoCloseFileDescriptor.h

@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2025, the Ladybird developers.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/RefCounted.h>
+#include <LibCore/System.h>
+
+namespace IPC {
+
+class AutoCloseFileDescriptor : public RefCounted<AutoCloseFileDescriptor> {
+public:
+    AutoCloseFileDescriptor(int fd)
+        : m_fd(fd)
+    {
+    }
+
+    ~AutoCloseFileDescriptor()
+    {
+        if (m_fd != -1)
+            (void)Core::System::close(m_fd);
+    }
+
+    int value() const { return m_fd; }
+
+    int take_fd()
+    {
+        int fd = m_fd;
+        m_fd = -1;
+        return fd;
+    }
+
+private:
+    int m_fd;
+};
+
+}

Libraries/LibIPC/Message.h

@@ -9,6 +9,7 @@
 
 #include <AK/Error.h>
 #include <AK/Vector.h>
+#include <LibIPC/AutoCloseFileDescriptor.h>
 #include <LibIPC/Transport.h>
 
 namespace IPC {

Libraries/LibIPC/TransportSocket.cpp

@@ -12,17 +12,6 @@
 
 namespace IPC {
 
-AutoCloseFileDescriptor::AutoCloseFileDescriptor(int fd)
-    : m_fd(fd)
-{
-}
-
-AutoCloseFileDescriptor::~AutoCloseFileDescriptor()
-{
-    if (m_fd != -1)
-        (void)Core::System::close(m_fd);
-}
-
 void SendQueue::enqueue_message(Vector<u8>&& bytes, Vector<int>&& fds)
 {
     Threading::MutexLocker locker(m_mutex);

Libraries/LibIPC/TransportSocket.h

@@ -10,6 +10,7 @@
 #include <AK/MemoryStream.h>
 #include <AK/Queue.h>
 #include <LibCore/Socket.h>
+#include <LibIPC/AutoCloseFileDescriptor.h>
 #include <LibIPC/File.h>
 #include <LibThreading/ConditionVariable.h>
 #include <LibThreading/MutexProtected.h>
@@ -18,24 +19,6 @@
 
 namespace IPC {
 
-class AutoCloseFileDescriptor : public RefCounted<AutoCloseFileDescriptor> {
-public:
-    AutoCloseFileDescriptor(int fd);
-    ~AutoCloseFileDescriptor();
-
-    int value() const { return m_fd; }
-
-    int take_fd()
-    {
-        int fd = m_fd;
-        m_fd = -1;
-        return fd;
-    }
-
-private:
-    int m_fd;
-};
-
 class SendQueue : public AtomicRefCounted<SendQueue> {
 public:
     enum class Running {