signal.cpp

/* Copyright (c) 2021 OceanBase and/or its affiliates. All rights reserved.
miniob is licensed under Mulan PSL v2.
You can use this software according to the terms and conditions of the Mulan PSL v2.
You may obtain a copy of Mulan PSL v2 at:
         http://license.coscl.org.cn/MulanPSL2
THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
See the Mulan PSL v2 for more details. */

//
// Created by Longda on 2010
//

#include "common/os/signal.h"
#include "common/log/log.h"
#include "pthread.h"
namespace common {

void setSignalHandler(int sig, sighandler_t func)
{
  struct sigaction newsa, oldsa;
  sigemptyset(&newsa.sa_mask);
  newsa.sa_flags = 0;
  newsa.sa_handler = func;
  int rc = sigaction(sig, &newsa, &oldsa);
  if (rc) {
    std::cerr << "Failed to set signal " << sig << SYS_OUTPUT_FILE_POS << SYS_OUTPUT_ERROR << std::endl;
  }
}

/*
** Set Singal handling Fucntion
*/
void setSignalHandler(sighandler_t func)
{
  setSignalHandler(SIGQUIT, func);
  setSignalHandler(SIGINT, func);
  setSignalHandler(SIGHUP, func);
  setSignalHandler(SIGTERM, func);
  signal(SIGPIPE, SIG_IGN);
}

void blockDefaultSignals(sigset_t *signal_set, sigset_t *old_set)
{
  sigemptyset(signal_set);
#ifndef DEBUG
  // SIGINT will effect our gdb debugging
  sigaddset(signal_set, SIGINT);
#endif
  sigaddset(signal_set, SIGTERM);
  sigaddset(signal_set, SIGUSR1);
  pthread_sigmask(SIG_BLOCK, signal_set, old_set);
}

void unBlockDefaultSignals(sigset_t *signal_set, sigset_t *old_set)
{
  sigemptyset(signal_set);
#ifndef DEBUG
  sigaddset(signal_set, SIGINT);
#endif
  sigaddset(signal_set, SIGTERM);
  sigaddset(signal_set, SIGUSR1);
  pthread_sigmask(SIG_UNBLOCK, signal_set, old_set);
}

void *waitForSignals(void *args)
{
  LOG_INFO("Start thread to wait signals.");
  sigset_t *signal_set = (sigset_t *)args;
  int sig_number = -1;
  while (true) {
    errno = 0;
    int ret = sigwait(signal_set, &sig_number);
    LOG_INFO("sigwait return value: %d, %d \n", ret, sig_number);
    if (ret != 0) {
      LOG_ERROR("error (%d) %s\n", errno, strerror(errno));
    }
  }
  return NULL;
}

void startWaitForSignals(sigset_t *signal_set)
{
  pthread_t pThread;
  pthread_attr_t pThreadAttrs;

  // create all threads as detached.  We will not try to join them.
  pthread_attr_init(&pThreadAttrs);
  pthread_attr_setdetachstate(&pThreadAttrs, PTHREAD_CREATE_DETACHED);

  pthread_create(&pThread, &pThreadAttrs, waitForSignals, (void *)signal_set);
}
}  // namespace common