Description:
------------
WDDX cannot be used to encode certain UTF8-encoded iso-8859-1 text. Particularily those iso-8859-1 characters, which after conversion to UTF-8 generate sequence of characters with value in 128-160 range, which are recognized as control characters. Control characters are turned into <char code="XX"/> sequence by WDDX.

wddx_deserialize() expects UTF-8 encoded string, and implicitly converts the text back to iso-8859-1 before deserializing the structure. This is done _before_
the <char code="XX"/> is replaced by the character. The < is thus recognized as part of the UTF-8 sequence, two-byte sequence is recoded to single-byte character and the result contains invalid XML (fragment 'char code="XX"/>'). Deserialization thus fails silently.

I.e.:
1. iso-8859-1 is Z (ord(Z) > 128)
2. UTF-8 string is XY
3. WDDX serializes that as X<char code="ord(Y)"/>
4. deserializer converts UTF-8 input to iso-8859-1 before
   starting deserialization, result is Bchar code="ord(Y)"/>
5. deserializer detects invalid XML and aborts the decode,
   returns empty string

Fix:

Only recode ASCII control characters to <char code="XX" /> sequence:

--- wddx.c.orig 2006-05-24 00:39:34.000000000 +0200
+++ wddx.c
@@ -399,7 +399,8 @@ static void php_wddx_serialize_string(wd
                                        break;

                                default:
-                                       if (iscntrl((int)*(unsigned char *)p)) {
+                                       if (iscntrl((int)*(unsigned char *)p)
+                                           && isascii((int)*(unsigned char *)p)) {
                                                FLUSH_BUF();
                                                sprintf(control_buf, WDDX_CHAR, *p);
                                                php_wddx_add_chunk(packet, control_buf);

Note - this patch also makes problem of Bug #37569 go away, but that patch is still useful to apply for code clarity.

This bug is probably same problem as Bug #35241.


Reproduce code:
---------------
On UNIX with iso-8859-1 locale or Windows with Windows-1250 locale:

var_dump(
    wddx_deserialize(wddx_serialize_value(utf8_encode(chr(200))))
    );


Expected result:
----------------
string(1) "&#268;"

Actual result:
--------------
string(0) ""