JSON issues

Hi,

I found few issues with the current ext/json during jsond testing:

1. The surrogate pairs for escaped Unicode characters are not handled
   correctly. For example JSON string "\uD811\uD811" (lead surrogate followed
   by lead surrogate) is accepted by the current implementation and converted
   to two ill-formatted UTF-8 characters. I would like to return NULL for such
   cases and set the new last json error code. I'm already using name
   JSON_ERROR_UTF16 for such case in jsond. If anyone thinks about better
   name, please let me know. This is apparently a bug but its fix require a
   new constant. I'm not sure about the version though. 5.6 only?

2. This is a valid JSON str: '{ "\u0000 key starting with zero": "value"
   }' . The problem is that it won't work when converted to stdClass as
   property name started with '\0' are used for mangled names.
   If you pass such string to json_decode, you will get a fatal error (the
   script is terminated). I would like to add a check to the JSON_Parser and
   return NULL from json_decode. It will requirea a new error code (new
   constant). Not sure about the name (any ideas welcomed) but it could be
   something like JSON_ERROR_MANGLED_PROPERTY_NAME. If user get such error,
   they can use assoc array (set second param for jsond_decode to true) and it
   will work. This should go to 5.6 as it's just an improvement that adds a
   new constant.

3. There is a small bug with number of digits when checking if it's a big
   number. The minus character is not considered for negative values which
   means that some really low numbers are considered as low even if they could
   be converted to long. It's a quick fix which should go to 5.4+

Any thoughts, comments or objections?

Jakub

Oops. The issue number 3 is fine. Got a bit confused as I was fixing such
case in jsond but the implementation is slightly different... The result is
correct on both.

So the real issues are just 1. and 2. :)

Thanks

Jakub