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/*
* Copyright (c) 2016, Ford Motor Company
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following
* disclaimer in the documentation and/or other materials provided with the
* distribution.
*
* Neither the name of the Ford Motor Company nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <csignal>
#include <cstdlib>
#include <stdint.h>
#include "utils/signals.h"
bool utils::UnsibscribeFromTermination() {
// Disable some system signals receiving in thread
// by blocking those signals
// (system signals processes only in the main thread)
// Mustn't block all signals!
// See "Advanced Programming in the UNIX Environment, 3rd Edition"
// (http://poincare.matf.bg.ac.rs/~ivana//courses/ps/sistemi_knjige/pomocno/apue.pdf,
// "12.8. Threads and Signals".
sigset_t signal_set;
sigemptyset(&signal_set);
sigaddset(&signal_set, SIGINT);
sigaddset(&signal_set, SIGTERM);
return !pthread_sigmask(SIG_BLOCK, &signal_set, NULL);
}
namespace {
bool CatchSIGSEGV(sighandler_t handler) {
struct sigaction act;
act.sa_handler = handler;
sigemptyset(&act.sa_mask);
act.sa_flags = 0;
return !sigaction(SIGSEGV, &act, NULL);
}
} // namespace
bool utils::WaitTerminationSignals(sighandler_t sig_handler) {
sigset_t signal_set;
int sig = -1;
sigemptyset(&signal_set);
sigaddset(&signal_set, SIGINT);
sigaddset(&signal_set, SIGTERM);
if (!CatchSIGSEGV(sig_handler)) {
return false;
}
if (!sigwait(&signal_set, &sig)) {
sig_handler(sig);
return true;
}
return false;
}
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