//
// Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2022
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#include "td/utils/port/detail/ThreadPthread.h"

char disable_linker_warning_about_empty_file_thread_pthread_cpp TD_UNUSED;

#if TD_THREAD_PTHREAD

#include "td/utils/misc.h"
#include "td/utils/port/detail/skip_eintr.h"
#if TD_NETBSD
#include "td/utils/ScopeGuard.h"
#endif

#include <pthread.h>
#if TD_FREEBSD
#include <pthread_np.h>
#endif
#include <sched.h>
#include <signal.h>
#if TD_FREEBSD
#include <sys/cpuset.h>
#endif
#if TD_FREEBSD || TD_OPENBSD || TD_NETBSD
#include <sys/sysctl.h>
#endif
#include <unistd.h>

namespace td {
namespace detail {
unsigned ThreadPthread::hardware_concurrency() {
// Linux and macOS
#if defined(_SC_NPROCESSORS_ONLN)
  {
    auto res = sysconf(_SC_NPROCESSORS_ONLN);
    if (res > 0) {
      return narrow_cast<unsigned>(res);
    }
  }
#endif

#if TD_FREEBSD || TD_OPENBSD || TD_NETBSD
#if defined(HW_AVAILCPU) && defined(CTL_HW)
  {
    int mib[2] = {CTL_HW, HW_AVAILCPU};
    int res{0};
    size_t len = sizeof(res);
    if (sysctl(mib, 2, &res, &len, nullptr, 0) == 0 && res != 0) {
      return res;
    }
  }
#endif

#if defined(HW_NCPU) && defined(CTL_HW)
  {
    int mib[2] = {CTL_HW, HW_NCPU};
    int res{0};
    size_t len = sizeof(res);
    if (sysctl(mib, 2, &res, &len, nullptr, 0) == 0 && res != 0) {
      return res;
    }
  }
#endif
#endif

  // Just in case
  return 8;
}

void ThreadPthread::set_name(CSlice name) {
#if defined(_GNU_SOURCE) && defined(__GLIBC_PREREQ)
#if __GLIBC_PREREQ(2, 12)
  pthread_setname_np(thread_, name.c_str());
#endif
#endif
}

void ThreadPthread::join() {
  if (is_inited_.get()) {
    is_inited_ = false;
    pthread_join(thread_, nullptr);
  }
}

void ThreadPthread::detach() {
  if (is_inited_.get()) {
    is_inited_ = false;
    pthread_detach(thread_);
  }
}

void ThreadPthread::send_real_time_signal(id thread_id, int real_time_signal_number) {
#ifdef SIGRTMIN
  pthread_kill(thread_id, SIGRTMIN + real_time_signal_number);
#endif
}

int ThreadPthread::do_pthread_create(pthread_t *thread, const pthread_attr_t *attr, void *(*start_routine)(void *),
                                     void *arg) {
  return pthread_create(thread, attr, start_routine, arg);
}

#if TD_HAVE_THREAD_AFFINITY
Status ThreadPthread::set_affinity_mask(id thread_id, uint64 mask) {
#if TD_LINUX || TD_FREEBSD
#if TD_FREEBSD
  cpuset_t cpuset;
#else
  cpu_set_t cpuset;
#endif
  CPU_ZERO(&cpuset);
  for (int j = 0; j < 64 && j < CPU_SETSIZE; j++) {
    if ((mask >> j) & 1) {
      CPU_SET(j, &cpuset);
    }
  }

  auto res = skip_eintr([&] { return pthread_setaffinity_np(thread_id, sizeof(cpuset), &cpuset); });
  if (res) {
    return OS_ERROR("Failed to set thread affinity mask");
  }
  return Status::OK();
#elif TD_NETBSD
  cpuset_t *cpuset = cpuset_create();
  if (cpuset == nullptr) {
    return OS_ERROR("Failed to create cpuset");
  }
  SCOPE_EXIT {
    cpuset_destroy(cpuset);
  };
  for (int j = 0; j < 64; j++) {
    if ((mask >> j) & 1) {
      if (cpuset_set(j, cpuset) != 0) {
        return OS_ERROR("Failed to set CPU identifier");
      }
    }
  }

  auto res = skip_eintr([&] { return pthread_setaffinity_np(thread_id, cpuset_size(cpuset), cpuset); });
  if (res) {
    return OS_ERROR("Failed to set thread affinity mask");
  }
  if (get_affinity_mask(thread_id) != mask) {
    return Status::Error("Failed to set exact thread affinity mask");
  }
  return Status::OK();
#else
  return Status::Error("Unsupported");
#endif
}

uint64 ThreadPthread::get_affinity_mask(id thread_id) {
#if TD_LINUX || TD_FREEBSD
#if TD_FREEBSD
  cpuset_t cpuset;
#else
  cpu_set_t cpuset;
#endif
  CPU_ZERO(&cpuset);
  auto res = skip_eintr([&] { return pthread_getaffinity_np(thread_id, sizeof(cpuset), &cpuset); });
  if (res) {
    return 0;
  }

  uint64 mask = 0;
  for (int j = 0; j < 64 && j < CPU_SETSIZE; j++) {
    if (CPU_ISSET(j, &cpuset)) {
      mask |= static_cast<uint64>(1) << j;
    }
  }
  return mask;
#elif TD_NETBSD
  cpuset_t *cpuset = cpuset_create();
  if (cpuset == nullptr) {
    return 0;
  }
  SCOPE_EXIT {
    cpuset_destroy(cpuset);
  };
  auto res = skip_eintr([&] { return pthread_getaffinity_np(thread_id, cpuset_size(cpuset), cpuset); });
  if (res) {
    return 0;
  }

  uint64 mask = 0;
  for (int j = 0; j < 64; j++) {
    if (cpuset_isset(j, cpuset) > 0) {
      mask |= static_cast<uint64>(1) << j;
    }
  }
  if (mask == 0) {
    // the mask wasn't set, all CPUs are allowed
    auto proc_count = sysconf(_SC_NPROCESSORS_ONLN);
    for (int j = 0; j < 64 && j < proc_count; j++) {
      mask |= static_cast<uint64>(1) << j;
    }
  }
  return mask;
#else
  return 0;
#endif
}
#endif

namespace this_thread_pthread {
ThreadPthread::id get_id() {
  return pthread_self();
}
}  // namespace this_thread_pthread

}  // namespace detail
}  // namespace td
#endif