From cb080346a437fee4f8ad2a887d45fc82d9f4873c Mon Sep 17 00:00:00 2001
From: Samuel Williams <samuel.williams@oriontransfer.co.nz>
Date: Fri, 17 Sep 2021 04:54:14 +1200
Subject: [PATCH] More elaborate exception handling. (#2700)

* More elaborate exception handling. Fixes #2699.

* Add TestIntegrationSingle#test_closed_listener

Co-authored-by: MSP-Greg <Greg.mpls@gmail.com>
---
 lib/puma/server.rb              |  5 ++++-
 test/helpers/integration.rb     |  8 ++++++--
 test/rackup/close_listeners.ru  |  6 ++++++
 test/test_integration_single.rb | 25 +++++++++++++++++++++++++
 4 files changed, 41 insertions(+), 3 deletions(-)
 create mode 100644 test/rackup/close_listeners.ru

diff --git a/lib/puma/server.rb b/lib/puma/server.rb
index 1309eb84..00429496 100644
--- a/lib/puma/server.rb
+++ b/lib/puma/server.rb
@@ -356,7 +356,10 @@ module Puma
                 pool << client
               end
             end
-          rescue Object => e
+          rescue IOError, Errno::EBADF
+            # In the case that any of the sockets are unexpectedly close.
+            raise
+          rescue StandardError => e
             @events.unknown_error e, nil, "Listen loop"
           end
         end
diff --git a/test/helpers/integration.rb b/test/helpers/integration.rb
index c013c7de..49a48e31 100644
--- a/test/helpers/integration.rb
+++ b/test/helpers/integration.rb
@@ -50,7 +50,7 @@ class TestIntegration < Minitest::Test
     assert(system(*args, out: File::NULL, err: File::NULL))
   end
 
-  def cli_server(argv, unix: false, config: nil)
+  def cli_server(argv, unix: false, config: nil, merge_err: false)
     if config
       config_file = Tempfile.new(%w(config .rb))
       config_file.write config
@@ -64,7 +64,11 @@ class TestIntegration < Minitest::Test
       @tcp_port = UniquePort.call
       cmd = "#{BASE} #{puma_path} #{config} -b tcp://#{HOST}:#{@tcp_port} #{argv}"
     end
-    @server = IO.popen(cmd, "r")
+    if merge_err
+      @server = IO.popen(cmd, "r", :err=>[:child, :out])
+    else
+      @server = IO.popen(cmd, "r")
+    end
     wait_for_server_to_boot
     @pid = @server.pid
     @server
diff --git a/test/rackup/close_listeners.ru b/test/rackup/close_listeners.ru
new file mode 100644
index 00000000..d7d37225
--- /dev/null
+++ b/test/rackup/close_listeners.ru
@@ -0,0 +1,6 @@
+require 'objspace'
+
+run lambda { |env|
+  ios = ObjectSpace.each_object(::TCPServer).to_a.tap { |a| a.each(&:close) }
+  [200, [], ["#{ios.inspect}\n"]]
+}
diff --git a/test/test_integration_single.rb b/test/test_integration_single.rb
index 09e28c79..f931e1a3 100644
--- a/test/test_integration_single.rb
+++ b/test/test_integration_single.rb
@@ -178,4 +178,29 @@ class TestIntegrationSingle < TestIntegration
     @server.close unless @server.closed?
     @server = nil
   end
+
+  # listener is closed 'externally' while Puma is in the IO.select statement
+  def test_closed_listener
+    skip_unless_signal_exist? :TERM
+
+    cli_server "test/rackup/close_listeners.ru", merge_err: true
+    read_body connect
+
+    begin
+      Timeout.timeout(5) do
+        begin
+          Process.kill :SIGTERM, @pid
+        rescue Errno::ESRCH
+        end
+        begin
+          Process.wait2 @pid
+        rescue Errno::ECHILD
+        end
+      end
+    rescue Timeout::Error
+      Process.kill :SIGKILL, @pid
+      assert false, "Process froze"
+    end
+    assert true
+  end
 end