4 files changed, 54 insertions, 3 deletions
diff --git a/ChangeLog b/ChangeLog
index e391d54656..9093b02937 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+Fri Nov 28 16:05:09 2014  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* io.c (copy_stream_body): should write in binary mode.  based on a
+	  patch by godfat (Lin Jen-Shin) at [ruby-core:56556].
+	  [ruby-core:56518] [Bug #8767]
+
+Fri Nov 28 16:05:09 2014  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* io.c (copy_stream_body): move common open flags.
+
 Fri Nov 28 16:01:44 2014  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* lib/rubygems/ssl_certs/AddTrustExternalCARoot{-2048,}.pem: add newer
diff --git a/io.c b/io.c
index 4757331f17..786b8883a8 100644
--- a/io.c
+++ b/io.c
@@ -10208,9 +10208,9 @@ copy_stream_body(VALUE arg)
 #ifdef O_BINARY
     if (src_fptr)
 	SET_BINARY_MODE_WITH_SEEK_CUR(src_fptr);
-    if (dst_fptr)
-	setmode(dst_fd, O_BINARY);
 #endif
+    if (dst_fptr)
+	rb_io_ascii8bit_binmode(dst_io);
 
     if (stp->src_offset == (off_t)-1 && src_fptr && src_fptr->rbuf.len) {
         size_t len = src_fptr->rbuf.len;
diff --git a/test/ruby/test_io.rb b/test/ruby/test_io.rb
index 89e347d2b3..acd7e654d4 100644
--- a/test/ruby/test_io.rb
+++ b/test/ruby/test_io.rb
@@ -770,6 +770,47 @@ class TestIO < Test::Unit::TestCase
     }
   end
 
+  def test_copy_stream_write_in_binmode
+    bug8767 = '[ruby-core:56518] [Bug #8767]'
+    mkcdtmpdir {
+      EnvUtil.with_default_internal(Encoding::UTF_8) do
+        # StringIO to object with to_path
+        bytes = "\xDE\xAD\xBE\xEF".force_encoding(Encoding::ASCII_8BIT)
+        src = StringIO.new(bytes)
+        dst = Object.new
+        def dst.to_path
+          "qux"
+        end
+        assert_nothing_raised(bug8767) {
+          IO.copy_stream(src, dst)
+        }
+        assert_equal(bytes, File.binread("qux"), bug8767)
+        assert_equal(4, src.pos, bug8767)
+      end
+    }
+  end
+
+  def test_copy_stream_read_in_binmode
+    bug8767 = '[ruby-core:56518] [Bug #8767]'
+    mkcdtmpdir {
+      EnvUtil.with_default_internal(Encoding::UTF_8) do
+        # StringIO to object with to_path
+        bytes = "\xDE\xAD\xBE\xEF".force_encoding(Encoding::ASCII_8BIT)
+        File.binwrite("qux", bytes)
+        dst = StringIO.new
+        src = Object.new
+        def src.to_path
+          "qux"
+        end
+        assert_nothing_raised(bug8767) {
+          IO.copy_stream(src, dst)
+        }
+        assert_equal(bytes, dst.string.b, bug8767)
+        assert_equal(4, dst.pos, bug8767)
+      end
+    }
+  end
+
   class Rot13IO
     def initialize(io)
       @io = io
diff --git a/version.h b/version.h
index 20e4531358..a89be87f6d 100644
--- a/version.h
+++ b/version.h
@@ -1,6 +1,6 @@
 #define RUBY_VERSION "2.0.0"
 #define RUBY_RELEASE_DATE "2014-11-28"
-#define RUBY_PATCHLEVEL 600
+#define RUBY_PATCHLEVEL 601
 
 #define RUBY_RELEASE_YEAR 2014
 #define RUBY_RELEASE_MONTH 11