rocksdb/test_util/mock_time_env.h

91 lines
3.4 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#pragma once
#include "rocksdb/env.h"
namespace ROCKSDB_NAMESPACE {
// NOTE: SpecialEnv offers most of this functionality, along with hooks
// for safe DB behavior under a mock time environment, so should be used
// instead of MockTimeEnv for DB tests.
class MockTimeEnv : public EnvWrapper {
public:
explicit MockTimeEnv(Env* base) : EnvWrapper(base) {}
virtual Status GetCurrentTime(int64_t* time_sec) override {
assert(time_sec != nullptr);
*time_sec = static_cast<int64_t>(current_time_us_ / kMicrosInSecond);
return Status::OK();
}
virtual uint64_t NowSeconds() { return current_time_us_ / kMicrosInSecond; }
virtual uint64_t NowMicros() override { return current_time_us_; }
virtual uint64_t NowNanos() override {
assert(current_time_us_ <= std::numeric_limits<uint64_t>::max() / 1000);
return current_time_us_ * 1000;
}
uint64_t RealNowMicros() { return target()->NowMicros(); }
void set_current_time(uint64_t time_sec) {
assert(time_sec < std::numeric_limits<uint64_t>::max() / kMicrosInSecond);
assert(time_sec * kMicrosInSecond >= current_time_us_);
current_time_us_ = time_sec * kMicrosInSecond;
}
// It's a fake sleep that just updates the Env current time, which is similar
// to `NoSleepEnv.SleepForMicroseconds()` and
// `SpecialEnv.MockSleepForMicroseconds()`.
// It's also similar to `set_current_time()`, which takes an absolute time in
// seconds, vs. this one takes the sleep in microseconds.
// Note: Not thread safe.
void MockSleepForMicroseconds(int micros) {
assert(micros >= 0);
assert(current_time_us_ + static_cast<uint64_t>(micros) >=
current_time_us_);
current_time_us_.fetch_add(micros);
}
void MockSleepForSeconds(int seconds) {
assert(seconds >= 0);
uint64_t micros = static_cast<uint64_t>(seconds) * kMicrosInSecond;
assert(current_time_us_ + micros >= current_time_us_);
current_time_us_.fetch_add(micros);
}
// TODO: this is a workaround for the different behavior on different platform
// for timedwait timeout. Ideally timedwait API should be moved to env.
// details: PR #7101.
void InstallTimedWaitFixCallback() {
SyncPoint::GetInstance()->DisableProcessing();
SyncPoint::GetInstance()->ClearAllCallBacks();
#if defined(OS_MACOSX) && !defined(NDEBUG)
// This is an alternate way (vs. SpecialEnv) of dealing with the fact
// that on some platforms, pthread_cond_timedwait does not appear to
// release the lock for other threads to operate if the deadline time
// is already passed. (TimedWait calls are currently a bad abstraction
// because the deadline parameter is usually computed from Env time,
// but is interpreted in real clock time.)
SyncPoint::GetInstance()->SetCallBack(
"InstrumentedCondVar::TimedWaitInternal", [&](void* arg) {
uint64_t time_us = *reinterpret_cast<uint64_t*>(arg);
if (time_us < this->RealNowMicros()) {
*reinterpret_cast<uint64_t*>(arg) = this->RealNowMicros() + 1000;
}
});
#endif // OS_MACOSX && !NDEBUG
SyncPoint::GetInstance()->EnableProcessing();
}
private:
std::atomic<uint64_t> current_time_us_{0};
};
} // namespace ROCKSDB_NAMESPACE