worker.h revision 356345 
1/*
2 * daemon/worker.h - worker that handles a pending list of requests.
3 *
4 * Copyright (c) 2007, NLnet Labs. All rights reserved.
5 *
6 * This software is open source.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * Redistributions of source code must retain the above copyright notice,
13 * this list of conditions and the following disclaimer.
14 *
15 * Redistributions in binary form must reproduce the above copyright notice,
16 * this list of conditions and the following disclaimer in the documentation
17 * and/or other materials provided with the distribution.
18 *
19 * Neither the name of the NLNET LABS nor the names of its contributors may
20 * be used to endorse or promote products derived from this software without
21 * specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
27 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35
36/**
37 * \file
38 *
39 * This file describes the worker structure that holds a list of
40 * pending requests and handles them.
41 */
42
43#ifndef DAEMON_WORKER_H
44#define DAEMON_WORKER_H
45
46#include "libunbound/worker.h"
47#include "util/netevent.h"
48#include "util/locks.h"
49#include "util/alloc.h"
50#include "util/data/msgreply.h"
51#include "util/data/msgparse.h"
52#include "daemon/stats.h"
53#include "util/module.h"
54#include "dnstap/dnstap.h"
55struct listen_dnsport;
56struct outside_network;
57struct config_file;
58struct daemon;
59struct listen_port;
60struct ub_randstate;
61struct regional;
62struct tube;
63struct daemon_remote;
64struct query_info;
65
66/** worker commands */
67enum worker_commands {
68	/** make the worker quit */
69	worker_cmd_quit,
70	/** obtain statistics */
71	worker_cmd_stats,
72	/** obtain statistics without statsclear */
73	worker_cmd_stats_noreset,
74	/** execute remote control command */
75	worker_cmd_remote
76};
77
78/**
79 * Structure holding working information for unbound.
80 * Holds globally visible information.
81 */
82struct worker {
83	/** the thread number (in daemon array). First in struct for debug. */
84	int thread_num;
85	/** global shared daemon structure */
86	struct daemon* daemon;
87	/** thread id */
88	ub_thread_type thr_id;
89	/** pipe, for commands for this worker */
90	struct tube* cmd;
91	/** the event base this worker works with */
92	struct comm_base* base;
93	/** the frontside listening interface where request events come in */
94	struct listen_dnsport* front;
95	/** the backside outside network interface to the auth servers */
96	struct outside_network* back;
97	/** ports to be used by this worker. */
98	int* ports;
99	/** number of ports for this worker */
100	int numports;
101	/** the signal handler */
102	struct comm_signal* comsig;
103	/** commpoint to listen to commands. */
104	struct comm_point* cmd_com;
105	/** timer for statistics */
106	struct comm_timer* stat_timer;
107	/** ratelimit for errors, time value */
108	time_t err_limit_time;
109	/** ratelimit for errors, packet count */
110	unsigned int err_limit_count;
111
112	/** random() table for this worker. */
113	struct ub_randstate* rndstate;
114	/** do we need to restart or quit (on signal) */
115	int need_to_exit;
116	/** allocation cache for this thread */
117	struct alloc_cache alloc;
118	/** per thread statistics */
119	struct ub_server_stats stats;
120	/** thread scratch regional */
121	struct regional* scratchpad;
122
123	/** module environment passed to modules, changed for this thread */
124	struct module_env env;
125
126#ifdef USE_DNSTAP
127	/** dnstap environment, changed for this thread */
128	struct dt_env dtenv;
129#endif
130};
131
132/**
133 * Create the worker structure. Bare bones version, zeroed struct,
134 * with backpointers only. Use worker_init on it later.
135 * @param daemon: the daemon that this worker thread is part of.
136 * @param id: the thread number from 0.. numthreads-1.
137 * @param ports: the ports it is allowed to use, array.
138 * @param n: the number of ports.
139 * @return: the new worker or NULL on alloc failure.
140 */
141struct worker* worker_create(struct daemon* daemon, int id, int* ports, int n);
142
143/**
144 * Initialize worker.
145 * Allocates event base, listens to ports
146 * @param worker: worker to initialize, created with worker_create.
147 * @param cfg: configuration settings.
148 * @param ports: list of shared query ports.
149 * @param do_sigs: if true, worker installs signal handlers.
150 * @return: false on error.
151 */
152int worker_init(struct worker* worker, struct config_file *cfg,
153	struct listen_port* ports, int do_sigs);
154
155/**
156 * Make worker work.
157 */
158void worker_work(struct worker* worker);
159
160/**
161 * Delete worker.
162 */
163void worker_delete(struct worker* worker);
164
165/**
166 * Send a command to a worker. Uses blocking writes.
167 * @param worker: worker to send command to.
168 * @param cmd: command to send.
169 */
170void worker_send_cmd(struct worker* worker, enum worker_commands cmd);
171
172/**
173 * Init worker stats - includes server_stats_init, outside network and mesh.
174 * @param worker: the worker to init
175 */
176void worker_stats_clear(struct worker* worker);
177
178#endif /* DAEMON_WORKER_H */
179