/*
* daemon/worker.h - worker that handles a pending list of requests.
*
* Copyright (c) 2007, NLnet Labs. All rights reserved.
*
* This software is open source.
*
* 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 NLNET LABS 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.
*/
/**
* \file
*
* This file describes the worker structure that holds a list of
* pending requests and handles them.
*/
/** worker commands */
enum worker_commands {
/** make the worker quit */
worker_cmd_quit,
/** obtain statistics */
worker_cmd_stats,
/** obtain statistics without statsclear */
worker_cmd_stats_noreset,
/** execute remote control command */
worker_cmd_remote,
/** for fast-reload, perform stop */
worker_cmd_reload_stop,
/** for fast-reload, start again */
worker_cmd_reload_start,
/** for fast-reload, poll to make sure worker has released data */
worker_cmd_reload_poll
};
/**
* Structure holding working information for unbound.
* Holds globally visible information.
*/
struct worker {
/** the thread number (in daemon array). First in struct for debug. */
int thread_num;
/** global shared daemon structure */
struct daemon* daemon;
/** thread id */
ub_thread_type thr_id;
#ifdef HAVE_GETTID
/** thread tid, the LWP id. */
pid_t thread_tid;
#endif
/** pipe, for commands for this worker */
struct tube* cmd;
/** the event base this worker works with */
struct comm_base* base;
/** the frontside listening interface where request events come in */
struct listen_dnsport* front;
/** the backside outside network interface to the auth servers */
struct outside_network* back;
/** ports to be used by this worker. */
int* ports;
/** number of ports for this worker */
int numports;
/** the signal handler */
struct comm_signal* comsig;
/** commpoint to listen to commands. */
struct comm_point* cmd_com;
/** timer for statistics */
struct comm_timer* stat_timer;
/** ratelimit for errors, time value */
time_t err_limit_time;
/** ratelimit for errors, packet count */
unsigned int err_limit_count;
/** random() table for this worker. */
struct ub_randstate* rndstate;
/** do we need to restart or quit (on signal) */
int need_to_exit;
/** allocation cache for this thread */
struct alloc_cache *alloc;
/** per thread statistics */
struct ub_server_stats stats;
/** thread scratch regional */
struct regional* scratchpad;
/** module environment passed to modules, changed for this thread */
struct module_env env;
#ifdef USE_DNSTAP
/** dnstap environment, changed for this thread */
struct dt_env dtenv;
#endif
/** reuse existing cache on reload if other conditions allow it. */
int reuse_cache;
};
/**
* Create the worker structure. Bare bones version, zeroed struct,
* with backpointers only. Use worker_init on it later.
* @param daemon: the daemon that this worker thread is part of.
* @param id: the thread number from 0.. numthreads-1.
* @param ports: the ports it is allowed to use, array.
* @param n: the number of ports.
* @return: the new worker or NULL on alloc failure.
*/
struct worker* worker_create(struct daemon* daemon, int id, int* ports, int n);
/**
* Initialize worker.
* Allocates event base, listens to ports
* @param worker: worker to initialize, created with worker_create.
* @param cfg: configuration settings.
* @param ports: list of shared query ports.
* @param do_sigs: if true, worker installs signal handlers.
* @return: false on error.
*/
int worker_init(struct worker* worker, struct config_file *cfg,
struct listen_port* ports, int do_sigs);
/**
* Make worker work.
*/
void worker_work(struct worker* worker);
