Make callback scheduling success/failure more explicit.

This CL introduces a new AsyncResult type which is yielded
from functions which may or may not schedule callbacks. Functions
of this type are changed to use AsyncResult rather than raw bools.

We also ensure that qsri callbacks are always fired, even if they
are not properly scheduled. This fixes a deadlock when VkImage
unboxing fails.

Bug: 238334576
Bug: 238333419
Test: Freeze detailed in 238334576 no longer occurs.

Change-Id: I4a3a752960d9900f674fa637f483c8b2100da068

1 files changed, 36 insertions, 0 deletions

diff --git a/base/include/base/AsyncResult.h b/base/include/base/AsyncResult.h
new file mode 100644
index 0000000..61843fa
--- /dev/null
+++ b/base/include/base/AsyncResult.h
@@ -0,0 +1,36 @@
+// Copyright 2022 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+class AsyncResult {
+   public:
+    // Describes the status of functions that may asynchronously schedule
+    // callbacks for execution.
+    enum ResultValue {
+        OK_AND_CALLBACK_SCHEDULED,
+        OK_AND_CALLBACK_NOT_SCHEDULED,
+        OK_AND_CALLBACK_FIRED,
+        FAIL_AND_CALLBACK_NOT_SCHEDULED,
+    };
+
+    AsyncResult() = default;
+    constexpr AsyncResult(ResultValue val) : value(val) {}
+    constexpr bool Succeeded() { return value != ResultValue::FAIL_AND_CALLBACK_NOT_SCHEDULED; }
+    constexpr bool CallbackScheduledOrFired() {
+        return value == OK_AND_CALLBACK_SCHEDULED || value == OK_AND_CALLBACK_FIRED;
+    }
+  private:
+    ResultValue value;
+
+};