/**
 * 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.
 */

#ifndef __PROCESS_UTILS_HPP__
#define __PROCESS_UTILS_HPP__

#include <iostream>
#include <sstream>

#include <stout/os.hpp>
#include <stout/strings.hpp>

namespace mesos {
namespace internal {
namespace utils {
namespace process {

inline Try<int> killtree(
    pid_t pid,
    int signal,
    bool killgroups,
    bool killsess,
    bool verbose)
{
  std::string cmdline;

  // TODO(Charles Reiss): Use a configuration option.
  if (os::hasenv("MESOS_KILLTREE")) {
    // Set by mesos-build-env.sh.
    cmdline = os::getenv("MESOS_KILLTREE");
  } else if (os::hasenv("MESOS_SOURCE_DIR")) {
    // Set by test harness for external tests.
    cmdline = os::getenv("MESOS_SOURCE_DIR") +
      "/src/scripts/killtree.sh";
  } else {
    cmdline = MESOS_LIBEXECDIR "/killtree.sh";
  }

  // Add the arguments.
  Try<std::string> args = strings::format(" -p %d -s %d", pid, signal);
  CHECK(!args.isError()) << args.error();
  cmdline += args.get();

  // Also add flags to kill all encountered groups and sessions.
  if (killgroups) cmdline += " -g";
  if (killsess) cmdline += " -x";
  if (verbose) cmdline += " -v";

  return os::shell(verbose ? &LOG(INFO) : NULL, cmdline);
}

} // namespace mesos {
} // namespace internal {
} // namespace utils {
} // namespace process {

#endif // __PROCESS_UTILS_HPP__