Crash the process when midi extraction times out
This is intended to recover from cases when the MIDI extractor gets
stuck in an infinite (or very long) loop.
The extractor code is 3rd party and hard to harden - this gives us
at least an eventual recovery.
Change-Id: I8d2fd85f91d1d2749c5620cf8518583076d2f6d7
Bug: 127313764
Bug: 127313537
Bug: 127313223
Bug: 127312550
Bug: 127310810
Bug: 126380818
diff --git a/media/libwatchdog/Android.bp b/media/libwatchdog/Android.bp
new file mode 100644
index 0000000..849623a
--- /dev/null
+++ b/media/libwatchdog/Android.bp
@@ -0,0 +1,36 @@
+// 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.
+
+cc_library {
+ name: "libwatchdog",
+ srcs: [
+ "Watchdog.cpp",
+ ],
+ export_include_dirs: ["include"],
+ shared_libs: [
+ "liblog",
+ ],
+ static_libs: [
+ "libbase",
+ ],
+ target: {
+ windows: {
+ enabled: false,
+ },
+ darwin: {
+ enabled: false,
+ },
+ },
+ apex_available: ["com.android.media"],
+}
diff --git a/media/libwatchdog/Watchdog.cpp b/media/libwatchdog/Watchdog.cpp
new file mode 100644
index 0000000..bb012b9
--- /dev/null
+++ b/media/libwatchdog/Watchdog.cpp
@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 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.
+ */
+
+#define LOG_TAG "Watchdog"
+
+#include <watchdog/Watchdog.h>
+
+#include <android-base/logging.h>
+#include <android-base/threads.h>
+#include <signal.h>
+#include <time.h>
+#include <cstring>
+#include <utils/Log.h>
+
+namespace android {
+
+Watchdog::Watchdog(::std::chrono::steady_clock::duration timeout) {
+ // Create the timer.
+ struct sigevent sev;
+ sev.sigev_notify = SIGEV_THREAD_ID;
+ sev.sigev_notify_thread_id = base::GetThreadId();
+ sev.sigev_signo = SIGABRT;
+ sev.sigev_value.sival_ptr = &mTimerId;
+ int err = timer_create(CLOCK_MONOTONIC, &sev, &mTimerId);
+ if (err != 0) {
+ PLOG(FATAL) << "Failed to create timer";
+ }
+
+ // Start the timer.
+ struct itimerspec spec;
+ memset(&spec, 0, sizeof(spec));
+ auto ns = std::chrono::duration_cast<std::chrono::nanoseconds>(timeout);
+ LOG_ALWAYS_FATAL_IF(timeout.count() <= 0, "Duration must be positive");
+ spec.it_value.tv_sec = ns.count() / 1000000000;
+ spec.it_value.tv_nsec = ns.count() % 1000000000;
+ err = timer_settime(mTimerId, 0, &spec, nullptr);
+ if (err != 0) {
+ PLOG(FATAL) << "Failed to start timer";
+ }
+}
+
+Watchdog::~Watchdog() {
+ // Delete the timer.
+ int err = timer_delete(mTimerId);
+ if (err != 0) {
+ PLOG(FATAL) << "Failed to delete timer";
+ }
+}
+
+} // namespace android
diff --git a/media/libwatchdog/include/watchdog/Watchdog.h b/media/libwatchdog/include/watchdog/Watchdog.h
new file mode 100644
index 0000000..2819f8a
--- /dev/null
+++ b/media/libwatchdog/include/watchdog/Watchdog.h
@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 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.
+ */
+
+#ifndef ANDROID_WATCHDOG_H
+#define ANDROID_WATCHDOG_H
+
+#include <chrono>
+#include <time.h>
+
+namespace android {
+
+/*
+ * An RAII-style object, which would crash the process if a timeout expires
+ * before the object is destroyed.
+ * The calling thread would be sent a SIGABORT, which would typically result in
+ * a stack trace.
+ *
+ * Sample usage:
+ * {
+ * Watchdog watchdog(std::chrono::milliseconds(10));
+ * DoSomething();
+ * }
+ * // If we got here, the function completed in time.
+ */
+class Watchdog final {
+public:
+ Watchdog(std::chrono::steady_clock::duration timeout);
+ ~Watchdog();
+
+private:
+ timer_t mTimerId;
+};
+
+} // namespace android
+
+#endif // ANDROID_WATCHDOG_H