commit 0faaa0bd7aa5dadea7c365fbb1f186da6eb097ef
author Dmitry Torokhov <dtor@google.com> Thu Sep 24 13:13:55 2015 -0700
committer Dmitry Torokhov <dtor@google.com> Tue Sep 29 13:27:16 2015 -0700
tree 2dc2ff68804e4cb736dd5348d2a755e5ca8a6b71
parent 115f93eeebf7f33b56ed090de70d6e8c733e5d88

Inputflinger: hook up key event replacement processing

Add handling of "replacement" key events in InputReader and EventHub by
consulting device's character key map (if exists) for presence of
replacement key code for given get code and meta state combination,
before passing it to InputDispatcher.

This enables defining special keys, such as ESC, on keyboards lacking
enough physical keys, via combination of normal keys and modifiers, for
example AltR + 1 => ESC.

Bug: 24504154

Change-Id: I7e36104808bedcf724436c1fbb63d37c35cca8af

services/inputflinger/EventHub.cpp

diff --git a/services/inputflinger/EventHub.cpp b/services/inputflinger/EventHub.cpp
index 6b60c7c..5859606 100644
--- a/services/inputflinger/EventHub.cpp
+++ b/services/inputflinger/EventHub.cpp
@@ -438,10 +438,12 @@
     return false;
 }
 
-status_t EventHub::mapKey(int32_t deviceId, int32_t scanCode, int32_t usageCode,
-        int32_t* outKeycode, uint32_t* outFlags) const {
+status_t EventHub::mapKey(int32_t deviceId,
+        int32_t scanCode, int32_t usageCode, int32_t metaState,
+        int32_t* outKeycode, int32_t* outMetaState, uint32_t* outFlags) const {
     AutoMutex _l(mLock);
     Device* device = getDeviceLocked(deviceId);
+    status_t status = NAME_NOT_FOUND;
 
     if (device) {
         // Check the key character map first.
@@ -449,22 +451,34 @@
         if (kcm != NULL) {
             if (!kcm->mapKey(scanCode, usageCode, outKeycode)) {
                 *outFlags = 0;
-                return NO_ERROR;
+                status = NO_ERROR;
             }
         }
 
         // Check the key layout next.
-        if (device->keyMap.haveKeyLayout()) {
+        if (status != NO_ERROR && device->keyMap.haveKeyLayout()) {
             if (!device->keyMap.keyLayoutMap->mapKey(
                     scanCode, usageCode, outKeycode, outFlags)) {
-                return NO_ERROR;
+                status = NO_ERROR;
+            }
+        }
+
+        if (status == NO_ERROR) {
+            if (kcm != NULL) {
+                kcm->tryRemapKey(*outKeycode, metaState, outKeycode, outMetaState);
+            } else {
+                *outMetaState = metaState;
             }
         }
     }
 
-    *outKeycode = 0;
-    *outFlags = 0;
-    return NAME_NOT_FOUND;
+    if (status != NO_ERROR) {
+        *outKeycode = 0;
+        *outFlags = 0;
+        *outMetaState = metaState;
+    }
+
+    return status;
 }
 
 status_t EventHub::mapAxis(int32_t deviceId, int32_t scanCode, AxisInfo* outAxisInfo) const {