mpm/simple/simple_children.c

	simple_children.c revision f997d134bcee6bfa4cd87b69acee96e80c5a358b
/* 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 "httpd.h"
#include "http_config.h"
#include "simple_types.h"
#include "simple_event.h"
#include "simple_run.h"
#include "apr_hash.h"

#define SPAWN_CHILDREN_INTERVAL (apr_time_from_sec(5))

static void
simple_kill_random_child(simple_core_t *sc)
{
  apr_thread_mutex_lock(sc->mtx);
  /* See comment in simple_spawn_child for why we check here. */
  if (!sc->run_single_process) {
  }
  apr_thread_mutex_unlock(sc->mtx);
}

static void
simple_spawn_child(simple_core_t *sc)
{
  apr_thread_mutex_lock(sc->mtx);
  /* Although we could cut this off 'earlier', and not even invoke this
   * function, I would like to keep the functions invoked when in debug mode
   * to be as close as possible to those when not in debug... So, we just skip
   * the actual spawn itself, but go through all of the motions...
   */
  if (!sc->run_single_process) {

  }
  apr_thread_mutex_unlock(sc->mtx);
}

void
simple_check_children_size(simple_core_t *sc,
                           void *baton)
{
  simple_register_timer(sc,
                        simple_check_children_size,
                        NULL,
                        SPAWN_CHILDREN_INTERVAL);
  unsigned int count;
  int wanted;
  int i;

  if (sc->run_single_process && sc->restart_num == 2) {
    static int run = 0;
    /* This is kinda of hack, but rather than spawning a child process,
     * we register the normal IO handlers in the main event loop....
     */
    if (run == 0) {
      simple_single_process_hack(sc);
      run++;
    }
  }

  {
    apr_thread_mutex_lock(sc->mtx);
    count = apr_hash_count(sc->children);
    wanted = sc->procmgr.proc_count;
    apr_thread_mutex_unlock(sc->mtx);
  }

  if (count > wanted) {
    /* kill some kids */
    int to_kill = count - wanted;
    for (i = 0;
         i < to_kill;
         i++)
    {
      simple_kill_random_child(sc);
    }
  }
  else if (count < wanted) {
    /* spawn some kids */
    int to_spawn = wanted - count;
    for (i = 0;
         i < to_spawn;
         i++)
    {
      simple_spawn_child(sc);
    }
  }
  else {
    /* juuuuust right. */
  }
}