[Xcb] [PATCH proto 08/12] xinput: GetDeviceProperty-reply: add align-pad at end

Christian Linhart chris at demorecorder.com
Fri Aug 15 11:36:16 PDT 2014

* all X11-replies must have a length which is a multiple of 4 bytes
* bitcases "8Bits" and "16bits" may have a length
  which is not a multiple of 4-bytes
  but they start on a 4-byte aligned position.
  Therefore the unpadded end of the request may not be 4-byte aligned
* Therefore this requires a 4-byte align-pad.

* The align pad had to be added in each relevant bitcase
  because adding it after the switch would cause the generator
  to abort. (which is OK because a <switch> has to be the last item
  of a struct, request or reply, according to the xcb-xml-spec)
 src/xinput.xml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/xinput.xml b/src/xinput.xml
index e0d887a..d6932ba 100644
--- a/src/xinput.xml
+++ b/src/xinput.xml
@@ -1082,20 +1082,22 @@ <request name="GetDeviceProperty" opcode="39">
                      distinguished exactly as their values don't have equal bits.
                     <enumref ref="PropertyFormat">8Bits</enumref>
                     <list type="CARD8" name="data8">
+                    <pad align="4" />
                     <enumref ref="PropertyFormat">16Bits</enumref>
                     <list type="CARD16" name="data16">
+                    <pad align="4" />
                     <enumref ref="PropertyFormat">32Bits</enumref>
                     <list type="CARD32" name="data32">

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