[Xcb] [PATCH libxcb 1/1] add support for eventstruct

[Christian Linhart]

eventstruct allows to use events as part of requests.
This is, e.g., needed by xcb_input_send_extension_event.

Signed-off-by: Christian Linhart <chris at demorecorder.com>
---
 src/c_client.py | 32 +++++++++++++++++++++++++++++++-
 src/xcb.h       | 12 ++++++++++++
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/src/c_client.py b/src/c_client.py
index b0eb47c..0cbdf30 100644
--- a/src/c_client.py
+++ b/src/c_client.py
@@ -433,15 +433,19 @@ def _c_type_setup(self, name, postfix):
 
         self.c_container = 'union' if self.is_union else 'struct'
         prev_varsized_field = None
         prev_varsized_offset = 0
         first_field_after_varsized = None
 
         for field in self.fields:
-            field.c_field_type = _t(field.field_type)
+            if field.type.is_event:
+                field.c_field_type = _t(field.field_type + ('event',))
+            else:
+                field.c_field_type = _t(field.field_type)
+
             field.c_field_const_type = ('' if field.type.nmemb == 1 else 'const ') + field.c_field_type
             field.c_field_name = _cpp(field.field_name)
             field.c_subscript = '[%d]' % field.type.nmemb if (field.type.nmemb and field.type.nmemb > 1) else ''
             field.c_pointer = ' ' if field.type.nmemb == 1 else '*'
 
             # correct the c_pointer field for variable size non-list types
             if not field.type.fixed_size() and field.c_pointer == ' ':
@@ -3152,14 +3156,36 @@ def c_request(self, name):
                     _c_accessors_list(self, field)
                 elif _c_field_needs_field_accessor(field):
                     _c_accessors_field(self, field)
     # We generate the manpage afterwards because _c_type_setup has been called.
     # TODO: what about aux helpers?
     _man_request(self, name, void=not self.reply, aux=False)
 
+
+def c_eventstruct(self, name):
+    #add fields that are needed to get the event-type in a generic way
+    self.fields.append( Field( tevent, tevent.name, 'event_header', False, True, True) )
+
+    if self.contains_ge_events:
+        #TODO: add header of ge-events as an extra field
+        raise Exception( 'eventstructs with ge-events are not yet supported' )
+
+    _c_type_setup(self, name, ())
+
+    #correct the format of the field names
+    for field in self.fields:
+        field.c_field_name = _n_item(field.c_field_name).lower()
+
+    _c_complex(self)
+    _c_iterator(self, name)
+
+    if not self.fixed_size():
+        #TODO: Create sizeof function (and maybe other accessors) for var-sized eventstructs
+        raise Exception( 'var sized eventstructs are not yet supported' )
+
 def c_event(self, name):
     '''
     Exported function that handles event declarations.
     '''
 
     # The generic event structure xcb_ge_event_t has the full_sequence field
     # at the 32byte boundary. That's why we've to inject this field into GE
@@ -3249,14 +3275,15 @@ def c_error(self, name):
 output = {'open'    : c_open,
           'close'   : c_close,
           'simple'  : c_simple,
           'enum'    : c_enum,
           'struct'  : c_struct,
           'union'   : c_union,
           'request' : c_request,
+          'eventstruct' : c_eventstruct,
           'event'   : c_event,
           'error'   : c_error,
           }
 
 # Boilerplate below this point
 
 # Check for the argument that specifies path to the xcbgen python package.
@@ -3292,14 +3319,17 @@ Failed to load the xcbgen Python package!
 Make sure that xcb/proto installed it on your Python path.
 If not, you will need to create a .pth file or define $PYTHONPATH
 to extend the path.
 Refer to the README file in xcb/proto for more info.
 ''')
     raise
 
+# predefined datatype globals.
+tevent = SimpleType(('xcb_raw_generic_event_t',), 32)
+
 # Ensure the man subdirectory exists
 try:
     os.mkdir('man')
 except OSError as e:
     if e.errno != errno.EEXIST:
         raise
 
diff --git a/src/xcb.h b/src/xcb.h
index 6873e79..cbc0f2b 100644
--- a/src/xcb.h
+++ b/src/xcb.h
@@ -139,14 +139,26 @@ typedef struct {
     uint8_t  pad0;           /**< Padding */
     uint16_t sequence;       /**< Sequence number */
     uint32_t pad[7];         /**< Padding */
     uint32_t full_sequence;  /**< full sequence */
 } xcb_generic_event_t;
 
 /**
+ * @brief Raw Generic event.
+ *
+ * A generic event structure as used on the wire, i.e., without the full_sequence field
+ */
+typedef struct {
+    uint8_t   response_type;  /**< Type of the response */
+    uint8_t  pad0;           /**< Padding */
+    uint16_t sequence;       /**< Sequence number */
+    uint32_t pad[7];         /**< Padding */
+} xcb_raw_generic_event_t;
+
+/**
  * @brief GE event
  *
  * An event as sent by the XGE extension. The length field specifies the
  * number of 4-byte blocks trailing the struct.
  *
  * @deprecated Since some fields in this struct have unfortunate names, it is
  * recommended to use xcb_ge_generic_event_t instead.
-- 
2.1.4