Close open file descriptors when calling Process.spawn

kernel/common/io.rb

@@ -454,13 +454,27 @@ def self.setup(io, fd, mode=nil, sync=false)
       end
     end
 
+    update_max_open_fd(fd)
+
     io.descriptor = fd
     io.mode       = mode || cur_mode
     io.sync       = !!sync
     io.sync     ||= STDOUT.fileno == fd if STDOUT.respond_to?(:fileno)
     io.sync     ||= STDERR.fileno == fd if STDERR.respond_to?(:fileno)
   end
 
+  @max_open_fd = 2
+
+  def self.update_max_open_fd(*fds)
+    fds.each do |fd|
+      @max_open_fd = fd if fd > @max_open_fd
+    end
+  end
+
+  def self.max_open_fd
+    @max_open_fd
+  end
+
   ##
   # Obtains a new duplicate descriptor for the current one.
   def initialize_copy(original) # :nodoc:

kernel/common/io18.rb

@@ -233,9 +233,11 @@ def self.pipe
 
     begin
       connect_pipe(lhs, rhs)
+      ::IO.update_max_open_fd(lhs.fileno, rhs.fileno)
     rescue Errno::EMFILE
       GC.run(true)
       connect_pipe(lhs, rhs)
+      ::IO.update_max_open_fd(lhs.fileno, rhs.fileno)
     end
 
     lhs.sync = true

kernel/common/io19.rb

@@ -673,9 +673,11 @@ def self.pipe(external_encoding=nil, internal_encoding=nil)
 
     begin
       connect_pipe(lhs, rhs)
+      ::IO.update_max_open_fd(lhs.fileno, rhs.fileno)
     rescue Errno::EMFILE
       GC.run(true)
       connect_pipe(lhs, rhs)
+      ::IO.update_max_open_fd(lhs.fileno, rhs.fileno)
     end
 
     external_encoding ||= Encoding.default_external

kernel/common/process19.rb

@@ -288,6 +288,15 @@ def self.exec(*args)
   def self.spawn(*args)
     env, prog, argv, redirects, options = Rubinius::Spawn.extract_arguments(*args)
 
+    unless options[:close_others] == false
+      3.upto(IO.max_open_fd).each do |fd|
+        begin
+          IO.for_fd(fd, :autoclose => false).close_on_exec = true
+        rescue Errno::EBADF
+        end
+      end
+    end
+
     IO.pipe do |read, write|
       pid = Process.fork do
         read.close

lib/19/open3.rb

@@ -199,7 +199,6 @@ def popen2e(*cmd, &block)
   module_function :popen2e
 
   def popen_run(cmd, opts, child_io, parent_io) # :nodoc:
-    parent_io.each {|io| io.close_on_exec = true }
     pid = spawn(*cmd, opts)
     wait_thr = Process.detach(pid)
     child_io.each {|io| io.close }