Enable detectable autorepeat

https://www.x.org/releases/current/doc/kbproto/xkbproto.html#Detectable_Autorepeat

Detectable autorepeat should only affect --release bindings. Currently,
when a user keeps a key pressed, we get multiple KeyPress and KeyRelease
events. With this change, we still get multiple KeyPress events, which
means that you can still keep a key pressed to repeatedly execute a
normal binding, but only one KeyRelease event when the key is physically
released.

Unfortunately, this change is not currently testable because detectable
autorepeat doesn't seem to work under Xephyr. AwesomeWM experienced the
same problem:
https://github.com/awesomeWM/awesome/commit/6f2424e90170be4acaa1d140f966ab6bb8a4d217

Fixes #3306

diff --git a/src/main.c b/src/main.c
index eb60bc8be853c934e8040e117e5f752b2ec21db8..eeeb3419c366b959feb01d5f7a9fefd27c540eda 100644 (file)
--- a/src/main.c
+++ b/src/main.c
@@ -642,7 +642,15 @@ int main(int argc, char *argv[]) {
          * XCB_XKB_PER_CLIENT_FLAG_LOOKUP_STATE_WHEN_GRABBED, will lead to the
          * X server sending us the full XKB state in KeyPress and KeyRelease:
          * https://cgit.freedesktop.org/xorg/xserver/tree/xkb/xkbEvents.c?h=xorg-server-1.20.0#n927
+         *
+         * XCB_XKB_PER_CLIENT_FLAG_DETECTABLE_AUTO_REPEAT enable detectable autorepeat:
+         * https://www.x.org/releases/current/doc/kbproto/xkbproto.html#Detectable_Autorepeat
+         * This affects bindings using the --release flag: instead of getting multiple KeyRelease
+         * events we get only one event when the key is physically released by the user.
          */
+        const uint32_t mask = XCB_XKB_PER_CLIENT_FLAG_GRABS_USE_XKB_STATE |
+                              XCB_XKB_PER_CLIENT_FLAG_LOOKUP_STATE_WHEN_GRABBED |
+                              XCB_XKB_PER_CLIENT_FLAG_DETECTABLE_AUTO_REPEAT;
         xcb_xkb_per_client_flags_reply_t *pcf_reply;
         /* The last three parameters are unset because they are only relevant
          * when using a feature called “automatic reset of boolean controls”:
@@ -653,20 +661,24 @@ int main(int argc, char *argv[]) {
             xcb_xkb_per_client_flags(
                 conn,
                 XCB_XKB_ID_USE_CORE_KBD,
-                XCB_XKB_PER_CLIENT_FLAG_GRABS_USE_XKB_STATE | XCB_XKB_PER_CLIENT_FLAG_LOOKUP_STATE_WHEN_GRABBED,
-                XCB_XKB_PER_CLIENT_FLAG_GRABS_USE_XKB_STATE | XCB_XKB_PER_CLIENT_FLAG_LOOKUP_STATE_WHEN_GRABBED,
+                mask,
+                mask,
                 0 /* uint32_t ctrlsToChange */,
                 0 /* uint32_t autoCtrls */,
                 0 /* uint32_t autoCtrlsValues */),
             NULL);
-        if (pcf_reply == NULL ||
-            !(pcf_reply->value & XCB_XKB_PER_CLIENT_FLAG_GRABS_USE_XKB_STATE)) {
-            ELOG("Could not set XCB_XKB_PER_CLIENT_FLAG_GRABS_USE_XKB_STATE\n");
-        }
-        if (pcf_reply == NULL ||
-            !(pcf_reply->value & XCB_XKB_PER_CLIENT_FLAG_LOOKUP_STATE_WHEN_GRABBED)) {
-            ELOG("Could not set XCB_XKB_PER_CLIENT_FLAG_LOOKUP_STATE_WHEN_GRABBED\n");
-        }
+
+#define PCF_REPLY_ERROR(_value)                                    \
+    do {                                                           \
+        if (pcf_reply == NULL || !(pcf_reply->value & (_value))) { \
+            ELOG("Could not set " #_value "\n");                   \
+        }                                                          \
+    } while (0)
+
+        PCF_REPLY_ERROR(XCB_XKB_PER_CLIENT_FLAG_GRABS_USE_XKB_STATE);
+        PCF_REPLY_ERROR(XCB_XKB_PER_CLIENT_FLAG_LOOKUP_STATE_WHEN_GRABBED);
+        PCF_REPLY_ERROR(XCB_XKB_PER_CLIENT_FLAG_DETECTABLE_AUTO_REPEAT);
+
         free(pcf_reply);
         xkb_base = extreply->first_event;
     }