base: add quick_exit emulation.

Bug: http://b/31468413
Change-Id: Ie15fcb8ff0613d01a0eb7437a2cb37283aa52bab
Test: mma, libbase_test on Linux/Windows
diff --git a/base/quick_exit.cpp b/base/quick_exit.cpp
new file mode 100644
index 0000000..d9fba03
--- /dev/null
+++ b/base/quick_exit.cpp
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2016 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 "android-base/quick_exit.h"
+
+#if !defined(__linux__)
+
+#include <mutex>
+#include <vector>
+
+#include "android-base/mutex.h"
+
+namespace android {
+namespace base {
+
+static std::mutex quick_exit_mutex;
+static std::vector<void(*)()> quick_exit_handlers;
+
+void quick_exit(int exit_code) {
+  std::lock_guard<std::mutex> lock(quick_exit_mutex);
+  for (auto it = quick_exit_handlers.rbegin(); it != quick_exit_handlers.rend(); ++it) {
+    (*it)();
+  }
+  _Exit(exit_code);
+}
+
+int at_quick_exit(void (*func)()) {
+  std::lock_guard<std::mutex> lock(quick_exit_mutex);
+  quick_exit_handlers.push_back(func);
+  return 0;
+}
+
+}  // namespace base
+}  // namespace android
+#endif