// Licensed to the Apache Software Foundation (ASF) under one

// or more contributor license agreements.  See the NOTICE file

// distributed with this work for additional information

// regarding copyright ownership.  The ASF licenses this file

// to you 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.

// This file is copied from

// https://github.com/apache/impala/blob/branch-2.9.0/be/src/util/os-util.h

// and modified by Doris

#pragma once

#include <cstdint>

#include <string>

#include "common/status.h"

namespace doris {

// Utility methods to read interesting values from /proc.

// TODO: Get stats for parent process.

// Container struct for statistics read from the /proc filesystem for a thread.

struct ThreadStats {

    int64_t user_ns;

    int64_t kernel_ns;

    int64_t iowait_ns;

    // Default constructor zeroes all members in case structure can't be filled by

    // GetThreadStats.

    ThreadStats() : user_ns(0), kernel_ns(0), iowait_ns(0) {}

};

// Populates ThreadStats object using a given buffer. The buffer is expected to

// conform to /proc/<pid>/task/<tid>/stat layout; an error will be returned otherwise.

//

// If 'name' is supplied, the extracted thread name will be written to it.

Status parse_stat(const std::string& buffer, std::string* name, ThreadStats* stats);

// Populates ThreadStats object for a given thread by reading from

// /proc/<pid>/task/<tid>/stat. Returns OK unless the file cannot be read or is in an

// unrecognised format, or if the kernel version is not modern enough.

Status get_thread_stats(int64_t tid, ThreadStats* stats);

// Disable core dumps for this process.

//

// This is useful particularly in tests where we have injected failures and don't

// want to generate a core dump from an "expected" crash.

void disable_core_dumps();

} // namespace doris