// 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.

// bthread - An M:N threading library to make applications more concurrent.

// Date: Tue Jul 10 17:40:58 CST 2012

#include <signal.h>
#include "bthread/interrupt_pthread.h"

namespace bthread {

// TODO: Make sure SIGURG is not used by user.
// This empty handler is simply for triggering EINTR in blocking syscalls.
void do_nothing_handler(int) {}

static pthread_once_t register_sigurg_once = PTHREAD_ONCE_INIT;

static void register_sigurg() {
    signal(SIGURG, do_nothing_handler);
}

int interrupt_pthread(pthread_t th) {
    pthread_once(&register_sigurg_once, register_sigurg);
    return pthread_kill(th, SIGURG);
}

}  // namespace bthread