1 files changed, 33 insertions, 0 deletions
diff --git a/test/test_cmogstored.rb b/test/test_cmogstored.rb
index 586000b..0dd920a 100644
--- a/test/test_cmogstored.rb
+++ b/test/test_cmogstored.rb
@@ -27,6 +27,25 @@ class Test_cmogstored < Test::Unit::TestCase
      assert_equal "a\nb\nc\nd\ne\n", client.get_file_data("puts")
    end
  
+  def test_garbage
+    add_host_device_domain
+    client = MogileFS::MogileFS.new :hosts => @hosts, :domain => @domain,
+                                    :timeout => 60
+    nr = 1024 * 1024 * 1024
+    client.new_file('giant', :largefile => :stream,
+                    :content_length => nr) do |io|
+      assert_instance_of MogileFS::NewFile::Stream, io
+      zero = Zero.new
+      before = GC.count
+      wr = IO.copy_stream(zero, io, nr)
+      after = GC.count
+      assert_equal nr, wr
+      assert_in_delta before, after, 1
+    end
+  end if IO.respond_to?(:copy_stream) && defined?(Zero) &&
+         GC.respond_to?(:count) && defined?(RUBY_ENGINE) &&
+         RUBY_ENGINE == 'ruby' && ENV['TEST_EXPENSIVE'].to_i != 0
+
    def test_stream_new_file
      add_host_device_domain
      client = MogileFS::MogileFS.new :hosts => @hosts, :domain => @domain
@@ -146,3 +165,17 @@ class Test_cmogstored < Test::Unit::TestCase
      end
    end
  end if `which cmogstored`.chomp.size > 0
+
+# The goal of this is to use a synthetic (non-IO) reader
+# to trigger the read/write loop of IO.copy_stream,
+# bypassing in-kernel mechanisms like sendfile for zero copy,
+# so we wrap the /dev/zero IO object:
+class Zero
+  def initialize
+    @in = File.open('/dev/zero', 'rb')
+  end
+
+  def read(len, buf)
+    @in.read(len, buf)
+  end
+end if File.readable?('/dev/zero')