Work in progress on writable encodingqstring-writable-encoding

Would help using adapt(unicode) to quote strings without a connection,
see ticket #331.

Currently in heisenbug state: if test_connection_wins_anyway and
test_encoding_default run (in this order), the latter fail because the
returned value is "'\xe8 '", with an extra space. Skipping the first
test, the second succeed.

The bad value is returned by the libpq:

    ql = PQescapeString(to+eq+1, from, len);

just returns len = 2 and an extra space in the string... meh.

1 files changed, 3 insertions, 0 deletions

diff --git a/psycopg/adapter_qstring.h b/psycopg/adapter_qstring.h
index b7b086f..8abdc5f 100644
--- a/psycopg/adapter_qstring.h
+++ b/psycopg/adapter_qstring.h
@@ -39,6 +39,9 @@ typedef struct {
     PyObject *buffer;
 
     connectionObject *conn;
+
+    const char *encoding;
+
 } qstringObject;
 
 #ifdef __cplusplus