Fix: make Crystal::EventLoop#remove(io) a class method

src/crystal/event_loop.cr

@@ -1,26 +1,30 @@
 abstract class Crystal::EventLoop
-  # Creates an event loop instance
-  def self.create : self
+  def self.backend_class
     {% if flag?(:wasi) %}
-      Crystal::EventLoop::Wasi.new
+      Crystal::EventLoop::Wasi
     {% elsif flag?(:unix) %}
       # TODO: enable more targets by default (need manual tests or fixes)
       {% if flag?("evloop=libevent") %}
-        Crystal::EventLoop::LibEvent.new
+        Crystal::EventLoop::LibEvent
       {% elsif flag?("evloop=epoll") || flag?(:android) || flag?(:linux) %}
-        Crystal::EventLoop::Epoll.new
+        Crystal::EventLoop::Epoll
       {% elsif flag?("evloop=kqueue") || flag?(:darwin) || flag?(:freebsd) %}
-        Crystal::EventLoop::Kqueue.new
+        Crystal::EventLoop::Kqueue
       {% else %}
-        Crystal::EventLoop::LibEvent.new
+        Crystal::EventLoop::LibEvent
       {% end %}
     {% elsif flag?(:win32) %}
-      Crystal::EventLoop::IOCP.new
+      Crystal::EventLoop::IOCP
     {% else %}
       {% raise "Event loop not supported" %}
     {% end %}
   end
 
+  # Creates an event loop instance
+  def self.create : self
+    backend_class.new
+  end
+
   @[AlwaysInline]
   def self.current : self
     Crystal::Scheduler.event_loop

src/crystal/event_loop/file_descriptor.cr

@@ -19,13 +19,20 @@ abstract class Crystal::EventLoop
 
     # Closes the file descriptor resource.
     abstract def close(file_descriptor : Crystal::System::FileDescriptor) : Nil
+  end
 
-    # Removes the file descriptor from the event loop. Can be used to free up
-    # memory resources associated with the file descriptor, as well as removing
-    # the file descriptor from kernel data structures.
-    #
-    # Called by `::IO::FileDescriptor#finalize` before closing the file
-    # descriptor. Errors shall be silently ignored.
-    abstract def remove(file_descriptor : Crystal::System::FileDescriptor) : Nil
+  # Removes the file descriptor from the event loop. Can be used to free up
+  # memory resources associated with the file descriptor, as well as removing
+  # the file descriptor from kernel data structures.
+  #
+  # Called by `::IO::FileDescriptor#finalize` before closing the file
+  # descriptor. Errors shall be silently ignored.
+  def self.remove(file_descriptor : Crystal::System::FileDescriptor) : Nil
+    backend_class.remove_impl(file_descriptor)
+  end
+
+  # Actual implementation for `.remove`. Must be implemented on a subclass of
+  # `Crystal::EventLoop` when needed.
+  protected def self.remove_impl(file_descriptor : Crystal::System::FileDescriptor) : Nil
   end
 end

src/crystal/event_loop/iocp.cr

@@ -201,9 +201,6 @@ class Crystal::EventLoop::IOCP < Crystal::EventLoop
     LibC.CancelIoEx(file_descriptor.windows_handle, nil) unless file_descriptor.system_blocking?
   end
 
-  def remove(file_descriptor : Crystal::System::FileDescriptor) : Nil
-  end
-
   private def wsa_buffer(bytes)
     wsabuf = LibC::WSABUF.new
     wsabuf.len = bytes.size
@@ -314,7 +311,4 @@ class Crystal::EventLoop::IOCP < Crystal::EventLoop
 
   def close(socket : ::Socket) : Nil
   end
-
-  def remove(socket : ::Socket) : Nil
-  end
 end

src/crystal/event_loop/libevent.cr

@@ -98,9 +98,6 @@ class Crystal::EventLoop::LibEvent < Crystal::EventLoop
     file_descriptor.evented_close
   end
 
-  def remove(file_descriptor : Crystal::System::FileDescriptor) : Nil
-  end
-
   def read(socket : ::Socket, slice : Bytes) : Int32
     evented_read(socket, "Error reading socket") do
       LibC.recv(socket.fd, slice, slice.size, 0).to_i32
@@ -194,9 +191,6 @@ class Crystal::EventLoop::LibEvent < Crystal::EventLoop
     socket.evented_close
   end
 
-  def remove(socket : ::Socket) : Nil
-  end
-
   def evented_read(target, errno_msg : String, &) : Int32
     loop do
       bytes_read = yield

src/crystal/event_loop/polling.cr

@@ -164,7 +164,7 @@ abstract class Crystal::EventLoop::Polling < Crystal::EventLoop
     evented_close(file_descriptor)
   end
 
-  def remove(file_descriptor : System::FileDescriptor) : Nil
+  protected def self.remove_impl(file_descriptor : System::FileDescriptor) : Nil
     internal_remove(file_descriptor)
   end
 
@@ -267,7 +267,7 @@ abstract class Crystal::EventLoop::Polling < Crystal::EventLoop
     evented_close(socket)
   end
 
-  def remove(socket : ::Socket) : Nil
+  protected def self.remove_impl(socket : ::Socket) : Nil
     internal_remove(socket)
   end
 
@@ -317,7 +317,7 @@ abstract class Crystal::EventLoop::Polling < Crystal::EventLoop
     end
   end
 
-  private def internal_remove(io)
+  private def self.internal_remove(io)
     return unless (index = io.__evloop_data).valid?
 
     Polling.arena.free(index) do |pd|

src/crystal/event_loop/socket.cr

@@ -62,13 +62,20 @@ abstract class Crystal::EventLoop
 
     # Closes the socket.
     abstract def close(socket : ::Socket) : Nil
+  end
 
-    # Removes the socket from the event loop. Can be used to free up memory
-    # resources associated with the socket, as well as removing the socket from
-    # kernel data structures.
-    #
-    # Called by `::Socket#finalize` before closing the socket. Errors shall be
-    # silently ignored.
-    abstract def remove(socket : ::Socket) : Nil
+  # Removes the socket from the event loop. Can be used to free up memory
+  # resources associated with the socket, as well as removing the socket from
+  # kernel data structures.
+  #
+  # Called by `::Socket#finalize` before closing the socket. Errors shall be
+  # silently ignored.
+  def self.remove(socket : ::Socket) : Nil
+    backend_class.remove_impl(socket)
+  end
+
+  # Actual implementation for `.remove`. Must be implemented on a subclass of
+  # `Crystal::EventLoop` when needed.
+  protected def self.remove_impl(socket : ::Socket) : Nil
   end
 end

src/crystal/event_loop/wasi.cr

@@ -53,9 +53,6 @@ class Crystal::EventLoop::Wasi < Crystal::EventLoop
     file_descriptor.evented_close
   end
 
-  def remove(file_descriptor : Crystal::System::FileDescriptor) : Nil
-  end
-
   def read(socket : ::Socket, slice : Bytes) : Int32
     evented_read(socket, "Error reading socket") do
       LibC.recv(socket.fd, slice, slice.size, 0).to_i32
@@ -88,9 +85,6 @@ class Crystal::EventLoop::Wasi < Crystal::EventLoop
     socket.evented_close
   end
 
-  def remove(socket : ::Socket) : Nil
-  end
-
   def evented_read(target, errno_msg : String, &) : Int32
     loop do
       bytes_read = yield

src/crystal/system/unix/process.cr

@@ -352,7 +352,7 @@ struct Crystal::System::Process
 
   private def self.reopen_io(src_io : IO::FileDescriptor, dst_io : IO::FileDescriptor)
     if src_io.closed?
-      Crystal::EventLoop.current.remove(dst_io)
+      Crystal::EventLoop.remove(dst_io)
       dst_io.file_descriptor_close
     else
       src_io = to_real_fd(src_io)

src/crystal/system/unix/signal.cr

@@ -111,7 +111,7 @@ module Crystal::System::Signal
   # descriptors of the parent process and send it received signals.
   def self.after_fork
     @@pipe.each do |pipe_io|
-      Crystal::EventLoop.current.remove(pipe_io)
+      Crystal::EventLoop.remove(pipe_io)
       pipe_io.file_descriptor_close { }
     end
   ensure

src/io/file_descriptor.cr

@@ -255,7 +255,7 @@ class IO::FileDescriptor < IO
   def finalize
     return if closed? || !close_on_finalize?
 
-    event_loop?.try(&.remove(self))
+    Crystal::EventLoop.remove(self)
     file_descriptor_close { } # ignore error
   end
 

src/socket.cr

@@ -430,7 +430,7 @@ class Socket < IO
   def finalize
     return if closed?
 
-    event_loop?.try(&.remove(self))
+    Crystal::EventLoop.remove(self)
     socket_close { } # ignore error
   end