pagespeed/system/system_thread_system.cc

/*
 * 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.
 */


#include "pagespeed/system/system_thread_system.h"

#include "base/logging.h"

#include "apr_thread_proc.h"  // NOLINT

namespace net_instaweb {

SystemThreadSystem::SystemThreadSystem() : may_start_threads_(false) {}
SystemThreadSystem::~SystemThreadSystem() {}

void SystemThreadSystem::PermitThreadStarting() {
  DCHECK(!may_start_threads_);
  may_start_threads_ = true;
}

void SystemThreadSystem::BeforeThreadRunHook() {
  // We disable all signals here, since the server we're hooking into is
  // probably using signals for something else and we don't want to get in the
  // way.  For example, we don't want Apache's use of SIGTERM to cause the
  // 'delete everything' handler to be run everywhere.  (This is only needed for
  // prefork, threaded MPMs do it already.)
  apr_setup_signal_thread();

  // If this fails you can get a backtrace from gdb by setting a breakpoint on
  // "pthread_create".
  DCHECK(may_start_threads_);
}

}  // namespace net_instaweb