From 16bf75dedffbc768dca2c94e55babff8d7a18111 Mon Sep 17 00:00:00 2001
From: Volo Zyko <volo.zyko@gmail.com>
Date: Thu, 31 Jul 2014 15:45:05 +0300
Subject: [PATCH] Extended the fix for issue #109 and added a test.

---
 include/cereal/archives/xml.hpp | 75 +++++++++++++++++++++++++++++++--
 unittests/basic_string.cpp      | 40 ++++++++++++++++++
 2 files changed, 112 insertions(+), 3 deletions(-)

diff --git a/include/cereal/archives/xml.hpp b/include/cereal/archives/xml.hpp
index 8f97e7c0..1c2ae6f5 100644
--- a/include/cereal/archives/xml.hpp
+++ b/include/cereal/archives/xml.hpp
@@ -238,8 +238,11 @@ namespace cereal
         itsOS.clear(); itsOS.seekp( 0, std::ios::beg );
         itsOS << value << std::ends;
 
+        // workaround rapidxml restriction on whitespace handling.
+        auto encoded = encode_cdata( itsOS.str() );
+
         // allocate strings for all of the data in the XML object
-        auto dataPtr = itsXML.allocate_string( itsOS.str().c_str() );
+        auto dataPtr = itsXML.allocate_string( encoded.c_str() );
 
         // allocate cdata and set its value
         auto cdata = itsXML.allocate_node( rapidxml::node_cdata );
@@ -317,6 +320,34 @@ namespace cereal
         }
       }; // NodeInfo
 
+      //! Encode only & and > in cdata text
+      /* Normally CDATA when saved to XML should not be changed in any way
+         but since rapidxml doesn't handle xml:space attribute in XML elements then
+         we use CDATA and do escaping of non-allowed characters manually. */
+      std::string encode_cdata( std::string const & text )
+      {
+        std::string res;
+        res.reserve( text.size() );
+
+        for( auto c : text )
+        {
+          if( c == '&' )
+          {
+            res.append( "&amp;" );
+          }
+          else if( c == '>' )
+          {
+            res.append( "&gt;" );
+          }
+          else
+          {
+            res.append( 1, c );
+          }
+        }
+
+        return res;
+      }
+
       //! @}
 
     private:
@@ -594,8 +625,8 @@ namespace cereal
 
         std::basic_istringstream<CharT, Traits> is( first_node->value() );
 
-        str.assign( std::istreambuf_iterator<CharT, Traits>( is ),
-                    std::istreambuf_iterator<CharT, Traits>() );
+        str = decode_cdata<CharT, Traits, Alloc>( std::istreambuf_iterator<CharT, Traits>( is ),
+                                                  std::istreambuf_iterator<CharT, Traits>() );
       }
 
       //! Loads the size of the current top node
@@ -676,6 +707,44 @@ namespace cereal
         const char * name;            //!< The NVP name for next next child node
       }; // NodeInfo
 
+      //! Decode & and > characters in cdata
+      /*  For details see explanation for XMLOutputArchive::encode_cdata(). */
+      template<class CharT, class Traits, class Alloc>
+      std::basic_string<CharT, Traits, Alloc> decode_cdata( std::istreambuf_iterator<CharT, Traits> start,
+                                                            const std::istreambuf_iterator<CharT, Traits>& end )
+      {
+        std::basic_string<CharT, Traits, Alloc> res;
+
+        for( ; start != end; ++start )
+        {
+          if( *start == '&' )
+          {
+            const auto first = *( ++start );
+            const auto second = *( ++start );
+            const auto third = *( ++start );
+
+            if( first == 'g' && second == 't' && third == ';' )
+            {
+              res.append( 1, '>' );
+            }
+            else if( first == 'a' && second == 'm' && third == 'p' && *( ++start ) == ';' )
+            {
+              res.append( 1, '&' );
+            }
+            else
+            {
+              throw Exception("Cannot decode cdata value");
+            }
+          }
+          else
+          {
+            res.append( 1, *start );
+          }
+        }
+
+        return res;
+      }
+
       //! @}
 
     private:
diff --git a/unittests/basic_string.cpp b/unittests/basic_string.cpp
index 25ec20b5..20ca9fab 100644
--- a/unittests/basic_string.cpp
+++ b/unittests/basic_string.cpp
@@ -125,3 +125,43 @@ BOOST_AUTO_TEST_CASE( json_string_basic )
   test_string_basic<cereal::JSONInputArchive, cereal::JSONOutputArchive>();
 }
 
+template <class IArchive, class OArchive, class T, size_t N, size_t M>
+void test_string_for_array(T (&strings)[N][M])
+{
+  for(size_t i=0; i<N; ++i)
+  {
+    std::basic_string<T> o_string = strings[i];
+
+    std::ostringstream os;
+    {
+      OArchive oar(os);
+      oar(o_string);
+    }
+
+    std::basic_string<T> i_string;
+
+    std::istringstream is(os.str());
+    {
+      IArchive iar(is);
+      iar(i_string);
+    }
+
+    BOOST_CHECK_EQUAL(i_string, o_string);
+  }
+}
+
+BOOST_AUTO_TEST_CASE( xml_string_issue109 )
+{
+  char strings[][20] = {
+    "some text",
+    " some text ",
+    "  ",
+    "    text    ",
+    " ]]> ",
+    " &gt; > ]]> ",
+    " < <]>] &lt; ",
+    " &amp; &   "
+  };
+
+  test_string_for_array<cereal::XMLInputArchive, cereal::XMLOutputArchive>(strings);
+}