Add second batch of fuzzers for libutils

This adds fuzzers for:
- CallStack
- Looper
- LruCache
- Printer
- ProcessCallStack
- PropertyMap
- RWLock
- RefBase
- StopWatch.
Test: Ran each fuzzer for 10 minutes. Rough coverage est. (likely far below actual value): 10.97%

Signed-off-by: Dylan Katz <dylan.katz@leviathansecurity.com>
Change-Id: I2f9f35c18b13338c282fb7f9c3ea4099ecb2c56f
diff --git a/libutils/Looper_fuzz.cpp b/libutils/Looper_fuzz.cpp
new file mode 100644
index 0000000..c3ae54e
--- /dev/null
+++ b/libutils/Looper_fuzz.cpp
@@ -0,0 +1,84 @@
+/*
+ * Copyright 2020 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 <sys/select.h>
+
+#include <iostream>
+
+#include <utils/Looper.h>
+
+#include "Looper_test_pipe.h"
+#include "fuzzer/FuzzedDataProvider.h"
+
+using android::Looper;
+using android::sp;
+
+// We don't want this to bog down fuzzing
+static constexpr int MAX_POLL_DELAY = 50;
+static constexpr int MAX_OPERATIONS = 500;
+
+void doNothing() {}
+void* doNothingPointer = reinterpret_cast<void*>(doNothing);
+
+static int noopCallback(int, int, void*) {
+    return 0;
+}
+
+std::vector<std::function<void(FuzzedDataProvider*, sp<Looper>, Pipe)>> operations = {
+        [](FuzzedDataProvider* dataProvider, sp<Looper> looper, Pipe) -> void {
+            looper->pollOnce(dataProvider->ConsumeIntegralInRange<int>(0, MAX_POLL_DELAY));
+        },
+        [](FuzzedDataProvider* dataProvider, sp<Looper> looper, Pipe) -> void {
+            looper->pollAll(dataProvider->ConsumeIntegralInRange<int>(0, MAX_POLL_DELAY));
+        },
+        // events and callback are nullptr
+        [](FuzzedDataProvider* dataProvider, sp<Looper> looper, Pipe pipeObj) -> void {
+            looper->addFd(pipeObj.receiveFd, dataProvider->ConsumeIntegral<int>(),
+                          dataProvider->ConsumeIntegral<int>(), nullptr, nullptr);
+        },
+        // Events is nullptr
+        [](FuzzedDataProvider* dataProvider, sp<Looper> looper, Pipe pipeObj) -> void {
+            looper->addFd(pipeObj.receiveFd, dataProvider->ConsumeIntegral<int>(),
+                          dataProvider->ConsumeIntegral<int>(), noopCallback, nullptr);
+        },
+        // callback is nullptr
+        [](FuzzedDataProvider* dataProvider, sp<Looper> looper, Pipe pipeObj) -> void {
+            looper->addFd(pipeObj.receiveFd, dataProvider->ConsumeIntegral<int>(),
+                          dataProvider->ConsumeIntegral<int>(), nullptr, doNothingPointer);
+        },
+        // callback and events both set
+        [](FuzzedDataProvider* dataProvider, sp<Looper> looper, Pipe pipeObj) -> void {
+            looper->addFd(pipeObj.receiveFd, dataProvider->ConsumeIntegral<int>(),
+                          dataProvider->ConsumeIntegral<int>(), noopCallback, doNothingPointer);
+        },
+
+        [](FuzzedDataProvider*, sp<Looper> looper, Pipe) -> void { looper->wake(); },
+        [](FuzzedDataProvider*, sp<Looper>, Pipe pipeObj) -> void { pipeObj.writeSignal(); }};
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+    Pipe pipeObj;
+    FuzzedDataProvider dataProvider(data, size);
+    sp<Looper> looper = new Looper(dataProvider.ConsumeBool());
+
+    size_t opsRun = 0;
+    while (dataProvider.remaining_bytes() > 0 && opsRun++ < MAX_OPERATIONS) {
+        uint8_t op = dataProvider.ConsumeIntegralInRange<uint8_t>(0, operations.size() - 1);
+        operations[op](&dataProvider, looper, pipeObj);
+    }
+    // Clear our pointer
+    looper.clear();
+    return 0;
+}