Handle stored files with general purpose bit 3 set

Signed-off-by: Sam Coward <scoward@pivotal.io>

lib/zip/entry.rb

@@ -500,7 +500,7 @@ module Zip
         end
       else
         zis = ::Zip::InputStream.new(@zipfile, local_header_offset)
-        zis.instance_variable_set(:@internal, true)
+        zis.instance_variable_set(:@complete_entry, self)
         zis.get_next_entry
         if block_given?
           begin

lib/zip/input_stream.rb

@@ -129,7 +129,7 @@ module Zip
       end
       if @current_entry && @current_entry.gp_flags & 8 == 8 && @current_entry.crc == 0 \
         && @current_entry.compressed_size == 0 \
-        && @current_entry.size == 0 && !@internal
+        && @current_entry.size == 0 && !@complete_entry
         raise GPFBit3Error,
               'General purpose flag Bit 3 is set so not possible to get proper info from local header.' \
               'Please use ::Zip::File instead of ::Zip::InputStream'
@@ -143,7 +143,11 @@ module Zip
       if @current_entry.nil?
         ::Zip::NullDecompressor
       elsif @current_entry.compression_method == ::Zip::Entry::STORED
-        ::Zip::PassThruDecompressor.new(@archive_io, @current_entry.size)
+        if @current_entry.gp_flags & 8 == 8 && @current_entry.crc == 0 && @current_entry.size == 0 && @complete_entry
+          ::Zip::PassThruDecompressor.new(@archive_io, @complete_entry.size)
+        else
+          ::Zip::PassThruDecompressor.new(@archive_io, @current_entry.size)
+        end
       elsif @current_entry.compression_method == ::Zip::Entry::DEFLATED
         header = @archive_io.read(@decrypter.header_bytesize)
         @decrypter.reset!(header)

test/file_test.rb

@@ -55,6 +55,12 @@ class ZipFileTest < MiniTest::Test
     assert_equal(2, zfRead.entries.length)
   end
 
+  def test_get_input_stream_stored_with_gpflag_bit3
+    ::Zip::File.open('test/data/gpbit3stored.zip') do |zf|
+      assert_equal("foo\n", zf.read("foo.txt"))
+    end
+  end
+
   def test_get_output_stream
     entryCount = nil
     ::Zip::File.open(TEST_ZIP.zip_name) do |zf|