avoid excessive garbage on uploads with Ruby 2.2+

This is a workaround for <https://bugs.ruby-lang.org/issues/13085>
since we use non-blocking sockets anyways.

1 files changed, 13 insertions, 0 deletions

diff --git a/lib/mogilefs/socket_common.rb b/lib/mogilefs/socket_common.rb
index 5ba8c10..9383731 100644
--- a/lib/mogilefs/socket_common.rb
+++ b/lib/mogilefs/socket_common.rb
@@ -56,4 +56,17 @@ module MogileFS::SocketCommon
   def readpartial(size, buf = "", timeout = 5)
     timed_read(size, buf, timeout) or raise EOFError, "end of file reached"
   end
+
+  # workaround for https://bugs.ruby-lang.org/issues/13085
+  # (excessive garbage from IO#write)
+  # XXX maybe this can be fixed for Ruby 2.5 final, but maybe not:
+  # Update this when Ruby 2.5 is released on 2017-12-25
+  if defined?(RUBY_ENGINE) && RUBY_ENGINE == 'ruby' &&
+     RUBY_VERSION.to_f >= 2.2 && RUBY_VERSION.to_f <= 2.5
+    def write(buf)
+      # Blocking TCP writes would error out long before one day,
+      # and MogileFS won't allow file creations which take over a day.
+      timed_write(buf, 86400)
+    end
+  end
 end