src/paimon/testing/utils/timezone_guard.h

/*
 * Copyright 2024-present Alibaba Inc.
 *
 * 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.
 */

#pragma once

#include <cstdlib>
#include <ctime>
#include <string>

namespace paimon::test {
class TimezoneGuard {
 public:
    explicit TimezoneGuard(const std::string& tz) {
        const char* original = std::getenv("TZ");
        if (original) {
            original_tz_ = original;
        } else {
            original_tz_.clear();
        }

        setenv("TZ", tz.c_str(), /*replace=*/1);
        tzset();
    }

    ~TimezoneGuard() {
        if (original_tz_.empty()) {
            unsetenv("TZ");
        } else {
            setenv("TZ", original_tz_.c_str(), /*replace=*/1);
        }
        tzset();
    }

 private:
    std::string original_tz_;
};

}  // namespace paimon::test