Xi: add versioning support.

Remember the version the client sent to us, so we can adjust our replies
accordingly. This requires the client to use the {major|minor}Version fields
in the GetExtensionVersion request. However, they were padding before, so we
must assume they are garbage if nbytes is non-zero. If nbytes is zero, the
client is probably a new client and we can handle it correctly.

1 files changed, 17 insertions, 0 deletions

diff --git a/Xi/getvers.c b/Xi/getvers.c
index 1e17eea5a..43a1a4d26 100644
--- a/Xi/getvers.c
+++ b/Xi/getvers.c
@@ -59,6 +59,7 @@ SOFTWARE.
 #include "inputstr.h"	/* DeviceIntPtr      */
 #include <X11/extensions/XI.h>
 #include <X11/extensions/XIproto.h>
+#include "exevents.h"
 #include "exglobals.h"
 
 #include "getvers.h"
@@ -93,6 +94,7 @@ int
 ProcXGetExtensionVersion(ClientPtr client)
 {
     xGetExtensionVersionReply rep;
+    XIClientPtr pXIClient;
 
     REQUEST(xGetExtensionVersionReq);
     REQUEST_AT_LEAST_SIZE(xGetExtensionVersionReq);
@@ -101,6 +103,21 @@ ProcXGetExtensionVersion(ClientPtr client)
 			  stuff->nbytes + 3) >> 2)
 	return BadLength;
 
+    pXIClient = dixLookupPrivate(&client->devPrivates, XIClientPrivateKey);
+
+    /* GetExtensionVersionReq before XI 2 didn't supply the client's
+     * major/minor. So we don't actually have a clue what they support.
+     * {major|minor}Version was added as part of XI, so if they are set, we
+     * know we can trust it. In this case the client must set nbytes to 0
+     * though, otherwise we have to assume that the version are padding
+     * garbage.
+     */
+    if (!stuff->nbytes) /* Client using XQueryInputVersion(). */
+    {
+        pXIClient->major_version = stuff->majorVersion;
+        pXIClient->minor_version = stuff->minorVersion;
+    } /* else version unknown, leave it at 0.0 */
+
     rep.repType = X_Reply;
     rep.RepType = X_GetExtensionVersion;
     rep.length = 0;