Fork command (unless windows) (#42)

lib/kontena/plugin/shell/session.rb

@@ -27,6 +27,18 @@ def run_command(buf)
         tokens = buf.split(/\s(?=(?:[^"]|"[^"]*")*$)/).map(&:strip)
         runner = Shell.command(tokens.first) || Shell.command(context.first) || Kontena::Plugin::Shell::KontenaCommand
         command = runner.new(context, tokens, self)
+        if fork_supported?
+          execute_with_fork(command)
+        else
+          execute_with_thread(command)
+        end
+      end
+
+      def fork_supported?
+        Process.respond_to?(:fork)
+      end
+
+      def execute_with_thread(command)
         old_trap = trap('INT', Proc.new { Thread.main[:command_thread] && Thread.main[:command_thread].kill })
         Thread.main[:command_thread] = Thread.new do
           command.run
@@ -35,6 +47,33 @@ def run_command(buf)
         trap('INT', old_trap)
       end
 
+      def execute_with_fork(command)
+        start = Time.now
+        pid = fork do
+          Process.setproctitle("kosh-runner")
+          command.run
+        end
+        trap('INT') {
+          begin
+            Process.kill('TERM', pid)
+          rescue Errno::ESRCH
+            raise SignalException, 'SIGINT'
+          end
+        }
+        Process.waitpid(pid)
+        if config_file_modified_since?(start)
+          puts ""
+          puts pastel.yellow("Config file has been modified, reloading configuration")
+          puts ""
+          config.reset_instance
+        end
+      end
+
+      def config_file_modified_since?(time)
+        return false unless config.config_file_available?
+        return true if File.mtime(config.config_filename) >= time
+      end
+
       def run
         puts File.read(__FILE__)[/__END__$(.*)/m, 1]
         puts "Kontena Shell v#{Kontena::Plugin::Shell::VERSION} (c) 2017 Kontena"

spec/kontena/plugin/shell/session_spec.rb

@@ -8,6 +8,7 @@
   let(:subject) { described_class.new(context) }
 
   it 'runs commands' do
+    allow(subject).to receive(:fork_supported?).and_return(false)
     expect(Readline).to receive(:readline).and_return('exit')
     expect{subject.run}.to output(/Bye/).to_stdout.and raise_error(SystemExit)
   end