commit 2984b7af4f7969cdc02dea6a1722635cc9a432dd
author Robert Carr <racarr@google.com> Mon Apr 13 17:06:45 2020 -0700
committer Rob Carr <racarr@google.com> Thu Apr 16 22:59:37 2020 +0000
tree 57fb768a9f2ed4d00209c7c060b44d5e66df8462
parent 8c0eb7fdbefb37f18b504bec3b0b2fc7cafd7872

InputDispatcher: Fix support for INPUT_FEATURE_NO_INPUT_CHANNEL

In preparation for an occlusion detection fix, we are going to begin
sending windows with NO_INPUT_CHANNEL to InputFlinger. There are 3
obstacles we address here:
   1. InputDispatcher ignores windows with no InputChannel when updating
      input windows. We modify the code to allow such windows if they have
      INPUT_FEATURE_NO_INPUT_CHANNEL.
   2. The parcelling code currently has an optimization to avoid sending the rest
      of the fields if token is null. We rebase this optimization on
      whether or not a name is set.
   3. InputWindowHandle::getName checks if there is a token to consider the window
      invalid. We instead check if a name is set.

Bug: 152064592
Test: Existing tests pass
Change-Id: I8a85f46b6c44866c7f73daafa5e8ff4c9251c366

include/input/InputWindow.h

diff --git a/include/input/InputWindow.h b/include/input/InputWindow.h
index edaf8f5..a695a8f 100644
--- a/include/input/InputWindow.h
+++ b/include/input/InputWindow.h
@@ -213,7 +213,7 @@
     }
 
     inline std::string getName() const {
-        return mInfo.token ? mInfo.name : "<invalid>";
+        return !mInfo.name.empty() ? mInfo.name : "<invalid>";
     }
 
     inline nsecs_t getDispatchingTimeout(nsecs_t defaultValue) const {

libs/input/InputWindow.cpp

diff --git a/libs/input/InputWindow.cpp b/libs/input/InputWindow.cpp
index 03ca459..6e4c97d 100644
--- a/libs/input/InputWindow.cpp
+++ b/libs/input/InputWindow.cpp
@@ -65,7 +65,7 @@
 }
 
 status_t InputWindowInfo::write(Parcel& output) const {
-    if (token == nullptr) {
+    if (name.empty()) {
         output.writeInt32(0);
         return OK;
     }
@@ -110,12 +110,7 @@
         return ret;
     }
 
-    sp<IBinder> token = from.readStrongBinder();
-    if (token == nullptr) {
-        return ret;
-    }
-
-    ret.token = token;
+    ret.token = from.readStrongBinder();
     ret.id = from.readInt32();
     ret.name = from.readString8().c_str();
     ret.layoutParamsFlags = from.readInt32();

services/inputflinger/dispatcher/InputDispatcher.cpp

diff --git a/services/inputflinger/dispatcher/InputDispatcher.cpp b/services/inputflinger/dispatcher/InputDispatcher.cpp
index 4ec61b0..403e21d 100644
--- a/services/inputflinger/dispatcher/InputDispatcher.cpp
+++ b/services/inputflinger/dispatcher/InputDispatcher.cpp
@@ -3598,8 +3598,8 @@
             if (canReceiveInput && !noInputChannel) {
                 ALOGV("Window handle %s has no registered input channel",
                       handle->getName().c_str());
+                continue;
             }
-            continue;
         }
 
         if (info->displayId != displayId) {