Pack requests using standard size and no alignment.

By default, Python's struct module automatically adds alignment padding
between successive structure members. We need precise control over the
layout of requests, so it's important that we not let it do that.

Signed-off-by: Julien Danjou <julien@danjou.info>

tools/py_client.py

@@ -476,24 +476,24 @@ def _py_request_helper(self, name, void, regular):
 
         (format, size, list) = _py_flush_format()
         if size > 0:
-            _py('        buf.write(pack(\'%s\', %s))', format, list)
+            _py('        buf.write(pack(\'=%s\', %s))', format, list)
 
         if field.type.is_expr:
-            _py('        buf.write(pack(\'%s\', %s))', field.type.py_format_str, _py_get_expr(field.type.expr))
+            _py('        buf.write(pack(\'=%s\', %s))', field.type.py_format_str, _py_get_expr(field.type.expr))
         elif field.type.is_pad:
             _py('        buf.write(pack(\'%sx\'))', field.type.nmemb)
         elif field.type.is_container:
             _py('        for elt in xcb.Iterator(%s, %d, \'%s\', False):', _n(field.field_name), field.type.py_format_len, _n(field.field_name))
-            _py('            buf.write(pack(\'%s\', *elt))', field.type.py_format_str)
+            _py('            buf.write(pack(\'=%s\', *elt))', field.type.py_format_str)
         elif field.type.is_list and field.type.member.is_simple:
             _py('        buf.write(str(buffer(array(\'%s\', %s))))', field.type.member.py_format_str, _n(field.field_name))
         else:
             _py('        for elt in xcb.Iterator(%s, %d, \'%s\', True):', _n(field.field_name), field.type.member.py_format_len, _n(field.field_name))
-            _py('            buf.write(pack(\'%s\', *elt))', field.type.member.py_format_str)
+            _py('            buf.write(pack(\'=%s\', *elt))', field.type.member.py_format_str)
 
     (format, size, list) = _py_flush_format()
     if size > 0:
-        _py('        buf.write(pack(\'%s\', %s))', format, list)
+        _py('        buf.write(pack(\'=%s\', %s))', format, list)
 
     _py('        return self.send_request(xcb.Request(buf.getvalue(), %s, %s, %s),', self.opcode, _b(void), _b(func_flags))
     _py('                                 %s()%s', func_cookie, ')' if void else ',')