Do not crash when server channel has closed

If the publisher has been destroyed (or, equivalently, if the server
channel was closed), the consumer should not crash. Instead, we should
allow consumer to exit gracefully.

In this CL, we specifically check for DEAD_OBJECT and drain the queue,
printing all of the events that will never be delivered to the publisher
for useful debugging purposes.

Bug: 305165753
Test: TEST=libinput_tests; m $TEST && $ANDROID_HOST_OUT/nativetest64/$TEST/$TEST
Flag: EXEMPT bugfix

Change-Id: I00973ebb87e0f59bfd3c0f58edf7355b28988c15

1 files changed, 15 insertions, 0 deletions

diff --git a/libs/input/InputConsumerNoResampling.cpp b/libs/input/InputConsumerNoResampling.cpp
index 2c0f77a814..cd8582182a 100644
--- a/libs/input/InputConsumerNoResampling.cpp
+++ b/libs/input/InputConsumerNoResampling.cpp
@@ -169,6 +169,12 @@ InputMessage createTimelineMessage(int32_t inputEventId, nsecs_t gpuCompletedTim
     msg.body.timeline.graphicsTimeline[GraphicsTimeline::PRESENT_TIME] = presentTime;
     return msg;
 }
+
+std::ostream& operator<<(std::ostream& out, const InputMessage& msg) {
+    out << ftl::enum_string(msg.header.type);
+    return out;
+}
+
 } // namespace
 
 // --- InputConsumerNoResampling ---
@@ -272,6 +278,15 @@ void InputConsumerNoResampling::processOutboundEvents() {
             return; // try again later
         }
 
+        if (result == DEAD_OBJECT) {
+            // If there's no one to receive events in the channel, there's no point in sending them.
+            // Drop all outbound events.
+            LOG(INFO) << "Channel " << mChannel->getName() << " died. Dropping outbound event "
+                      << outboundMsg;
+            mOutboundQueue.pop();
+            setFdEvents(0);
+            continue;
+        }
         // Some other error. Give up
         LOG(FATAL) << "Failed to send outbound event on channel '" << mChannel->getName()
                    << "'.  status=" << statusToString(result) << "(" << result << ")";