avoid StringIO#binmode for the next few years

Apparently, StringIO#binmode has been totally broken in 1.9+ and
I've always hidden this bug with the combination of an explicit
string and magic "encoding: binary" comments :x

ref: https://bugs.ruby-lang.org/issues/11945

2 files changed, 11 insertions, 8 deletions

diff --git a/lib/yahns/http_client.rb b/lib/yahns/http_client.rb
index 109b545..c300742 100644
--- a/lib/yahns/http_client.rb
+++ b/lib/yahns/http_client.rb
@@ -3,7 +3,7 @@
 # License: GPL-3.0+ (https://www.gnu.org/licenses/gpl-3.0.txt)
 # frozen_string_literal: true
 class Yahns::HttpClient < Kgio::Socket # :nodoc:
-  NULL_IO = StringIO.new.binmode # :nodoc:
+  NULL_IO = StringIO.new(''.dup) # :nodoc:
 
   include Yahns::HttpResponse
   QEV_FLAGS = Yahns::Queue::QEV_RD # used by acceptor
diff --git a/lib/yahns/http_context.rb b/lib/yahns/http_context.rb
index c7258ad..10be062 100644
--- a/lib/yahns/http_context.rb
+++ b/lib/yahns/http_context.rb
@@ -80,13 +80,16 @@ module Yahns::HttpContext # :nodoc:
 
   def tmpio_for(len, env)
     # short requests are most common
-    return StringIO.new.binmode if len && len <= @client_body_buffer_size;
-
-    # too big or chunked, unknown length
-    tmp = @input_buffer_tmpdir
-    mbs = @client_max_body_size
-    tmp = mbs ? Yahns::CapInput.new(mbs, tmp) : Yahns::TmpIO.new(tmp)
-    (env['rack.tempfiles'] ||= []) << tmp
+    if len && len <= @client_body_buffer_size;
+      # Can't use binmode, yet: https://bugs.ruby-lang.org/issues/11945
+      tmp = StringIO.new
+      tmp.set_encoding(Encoding::ASCII_8BIT)
+    else # too big or chunked, unknown length
+      tmp = @input_buffer_tmpdir
+      mbs = @client_max_body_size
+      tmp = mbs ? Yahns::CapInput.new(mbs, tmp) : Yahns::TmpIO.new(tmp)
+      (env['rack.tempfiles'] ||= []) << tmp
+    end
     tmp
   end
 end