VILLASnode/common/lib/cpuset.cpp

/* Human readable cpusets.
 *
 * Author: Steffen Vogel <github@daniel-krebs.net>
 * SPDX-FileCopyrightText: 2014-2023 Institute for Automation of Complex Power Systems, RWTH Aachen University
 * SPDX-License-Identifier: Apache-2.0
 */

#include <villas/cpuset.hpp>
#include <villas/utils.hpp>

using namespace villas::utils;

#ifdef __linux__

CpuSet::CpuSet(uintmax_t iset) : CpuSet() {
  zero();

  for (size_t i = 0; i < num_cpus; i++) {
    if (iset & (1L << i))
      set(i);
  }
}

CpuSet::CpuSet(const std::string &str) : CpuSet() {
  size_t endpos, start, end;

  for (auto token : tokenize(str, ",")) {
    auto sep = token.find('-');

    if (sep == std::string::npos) {
      start = std::stoi(token, &endpos);

      if (token.begin() + endpos != token.end())
        throw std::invalid_argument("Not a valid CPU set");

      if (start < num_cpus)
        set(start);
    } else {
      start = std::stoi(token, &endpos);

      if (token.begin() + endpos != token.begin() + sep)
        throw std::invalid_argument("Not a valid CPU set");

      auto token2 = token.substr(endpos + 1);

      end = std::stoi(token2, &endpos);

      if (token2.begin() + endpos != token2.end())
        throw std::invalid_argument("Not a valid CPU set");

      for (size_t i = start; i <= end && i < num_cpus; i++)
        set(i);
    }
  }
}

CpuSet::CpuSet(const char *str) : CpuSet(std::string(str)) {}

CpuSet::operator uintmax_t() {
  uintmax_t iset = 0;

  for (size_t i = 0; i < num_cpus; i++) {
    if (isSet(i))
      iset |= 1ULL << i;
  }

  return iset;
}

CpuSet::operator std::string() {
  std::stringstream ss;

  bool first = true;

  for (size_t i = 0; i < num_cpus; i++) {
    if (isSet(i)) {
      size_t run = 0;
      for (size_t j = i + 1; j < num_cpus; j++) {
        if (!isSet(j))
          break;

        run++;
      }

      if (first)
        first = false;
      else
        ss << ",";

      ss << i;

      if (run == 1) {
        ss << "," << (i + 1);
        i++;
      } else if (run > 1) {
        ss << "-" << (i + run);
        i += run;
      }
    }
  }

  return ss.str();
}

#endif // __linux__