Set HAL response functions after framework sets all of theirs.

Bug: 207695009
Test: Build with ag/16322062 and a handful of patches from b/207695009,
      try to use telephony stack
Change-Id: I74afe105a22a24efa0c38de20c75beffc58b144f
diff --git a/radio/aidl/compat/libradiocompat/CallbackManager.cpp b/radio/aidl/compat/libradiocompat/CallbackManager.cpp
new file mode 100644
index 0000000..c2eaed1
--- /dev/null
+++ b/radio/aidl/compat/libradiocompat/CallbackManager.cpp
@@ -0,0 +1,84 @@
+/*
+ * Copyright (C) 2021 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.
+ */
+
+#include <libradiocompat/CallbackManager.h>
+
+#include <android-base/logging.h>
+
+using namespace std::literals::chrono_literals;
+
+namespace android::hardware::radio::compat {
+
+/**
+ * How much setter thread will wait with setting response functions after the last
+ * setResponseFunctions call from the framework. Subsequent calls from the framework reset the
+ * clock, so this number should be larger than the longest time between setResponseFunctions calls
+ * from the framework.
+ *
+ * Real world measurements with Cuttlefish give <10ms delay between Modem and Data and <2ms delays
+ * between all others.
+ */
+static constexpr auto kDelayedSetterDelay = 100ms;
+
+CallbackManager::CallbackManager(std::shared_ptr<DriverContext> context, sp<V1_5::IRadio> hidlHal)
+    : mHidlHal(hidlHal),
+      mRadioResponse(sp<compat::RadioResponse>::make(context)),
+      mRadioIndication(sp<compat::RadioIndication>::make(context)),
+      mDelayedSetterThread(&CallbackManager::delayedSetterThread, this) {}
+
+CallbackManager::~CallbackManager() {
+    {
+        std::unique_lock<std::mutex> lock(mDelayedSetterGuard);
+        mDelayedSetterDeadline = std::nullopt;
+        mDestroy = true;
+        mDelayedSetterCv.notify_all();
+    }
+    mDelayedSetterThread.join();
+}
+
+RadioResponse& CallbackManager::response() const {
+    return *mRadioResponse;
+}
+
+void CallbackManager::setResponseFunctionsDelayed() {
+    std::unique_lock<std::mutex> lock(mDelayedSetterGuard);
+    mDelayedSetterDeadline = std::chrono::steady_clock::now() + kDelayedSetterDelay;
+    mDelayedSetterCv.notify_all();
+}
+
+void CallbackManager::delayedSetterThread() {
+    while (!mDestroy) {
+        std::unique_lock<std::mutex> lock(mDelayedSetterGuard);
+        auto deadline = mDelayedSetterDeadline;
+
+        // not waiting to set response functions
+        if (!deadline) {
+            mDelayedSetterCv.wait(lock);
+            continue;
+        }
+
+        // waiting to set response functions, but not yet
+        if (*deadline > std::chrono::steady_clock::now()) {
+            mDelayedSetterCv.wait_until(lock, *deadline);
+            continue;
+        }
+
+        mHidlHal->setResponseFunctions(mRadioResponse, mRadioIndication).assertOk();
+        mDelayedSetterDeadline = std::nullopt;
+    }
+}
+
+}  // namespace android::hardware::radio::compat