1/* $Id$ */
2
3/***
4  This file is part of avahi.
5
6  avahi is free software; you can redistribute it and/or modify it
7  under the terms of the GNU Lesser General Public License as
8  published by the Free Software Foundation; either version 2.1 of the
9  License, or (at your option) any later version.
10
11  avahi is distributed in the hope that it will be useful, but WITHOUT
12  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13  or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
14  Public License for more details.
15
16  You should have received a copy of the GNU Lesser General Public
17  License along with avahi; if not, write to the Free Software
18  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
19  USA.
20***/
21
22#ifdef HAVE_CONFIG_H
23#include <config.h>
24#endif
25
26#include <time.h>
27#include <stdio.h>
28#include <stdlib.h>
29#include <assert.h>
30
31#include <avahi-client/client.h>
32#include <avahi-client/publish.h>
33
34#include <avahi-common/alternative.h>
35#include <avahi-common/simple-watch.h>
36#include <avahi-common/malloc.h>
37#include <avahi-common/error.h>
38#include <avahi-common/timeval.h>
39
40static AvahiEntryGroup *group = NULL;
41static AvahiSimplePoll *simple_poll = NULL;
42static char *name = NULL;
43
44static void create_services(AvahiClient *c);
45
46static void entry_group_callback(AvahiEntryGroup *g, AvahiEntryGroupState state, AVAHI_GCC_UNUSED void *userdata) {
47    assert(g == group || group == NULL);
48    group = g;
49
50    /* Called whenever the entry group state changes */
51
52    switch (state) {
53        case AVAHI_ENTRY_GROUP_ESTABLISHED :
54            /* The entry group has been established successfully */
55            fprintf(stderr, "Service '%s' successfully established.\n", name);
56            break;
57
58        case AVAHI_ENTRY_GROUP_COLLISION : {
59            char *n;
60
61            /* A service name collision with a remote service
62             * happened. Let's pick a new name */
63            n = avahi_alternative_service_name(name);
64            avahi_free(name);
65            name = n;
66
67            fprintf(stderr, "Service name collision, renaming service to '%s'\n", name);
68
69            /* And recreate the services */
70            create_services(avahi_entry_group_get_client(g));
71            break;
72        }
73
74        case AVAHI_ENTRY_GROUP_FAILURE :
75
76            fprintf(stderr, "Entry group failure: %s\n", avahi_strerror(avahi_client_errno(avahi_entry_group_get_client(g))));
77
78            /* Some kind of failure happened while we were registering our services */
79            avahi_simple_poll_quit(simple_poll);
80            break;
81
82        case AVAHI_ENTRY_GROUP_UNCOMMITED:
83        case AVAHI_ENTRY_GROUP_REGISTERING:
84            ;
85    }
86}
87
88static void create_services(AvahiClient *c) {
89    char *n, r[128];
90    int ret;
91    assert(c);
92
93    /* If this is the first time we're called, let's create a new
94     * entry group if necessary */
95
96    if (!group)
97        if (!(group = avahi_entry_group_new(c, entry_group_callback, NULL))) {
98            fprintf(stderr, "avahi_entry_group_new() failed: %s\n", avahi_strerror(avahi_client_errno(c)));
99            goto fail;
100        }
101
102    /* If the group is empty (either because it was just created, or
103     * because it was reset previously, add our entries.  */
104
105    if (avahi_entry_group_is_empty(group)) {
106        fprintf(stderr, "Adding service '%s'\n", name);
107
108        /* Create some random TXT data */
109        snprintf(r, sizeof(r), "random=%i", rand());
110
111        /* We will now add two services and one subtype to the entry
112         * group. The two services have the same name, but differ in
113         * the service type (IPP vs. BSD LPR). Only services with the
114         * same name should be put in the same entry group. */
115
116        /* Add the service for IPP */
117        if ((ret = avahi_entry_group_add_service(group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, 0, name, "_ipp._tcp", NULL, NULL, 651, "test=blah", r, NULL)) < 0) {
118
119            if (ret == AVAHI_ERR_COLLISION)
120                goto collision;
121
122            fprintf(stderr, "Failed to add _ipp._tcp service: %s\n", avahi_strerror(ret));
123            goto fail;
124        }
125
126        /* Add the same service for BSD LPR */
127        if ((ret = avahi_entry_group_add_service(group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, 0, name, "_printer._tcp", NULL, NULL, 515, NULL)) < 0) {
128
129            if (ret == AVAHI_ERR_COLLISION)
130                goto collision;
131
132            fprintf(stderr, "Failed to add _printer._tcp service: %s\n", avahi_strerror(ret));
133            goto fail;
134        }
135
136        /* Add an additional (hypothetic) subtype */
137        if ((ret = avahi_entry_group_add_service_subtype(group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, 0, name, "_printer._tcp", NULL, "_magic._sub._printer._tcp") < 0)) {
138            fprintf(stderr, "Failed to add subtype _magic._sub._printer._tcp: %s\n", avahi_strerror(ret));
139            goto fail;
140        }
141
142        /* Tell the server to register the service */
143        if ((ret = avahi_entry_group_commit(group)) < 0) {
144            fprintf(stderr, "Failed to commit entry group: %s\n", avahi_strerror(ret));
145            goto fail;
146        }
147    }
148
149    return;
150
151collision:
152
153    /* A service name collision with a local service happened. Let's
154     * pick a new name */
155    n = avahi_alternative_service_name(name);
156    avahi_free(name);
157    name = n;
158
159    fprintf(stderr, "Service name collision, renaming service to '%s'\n", name);
160
161    avahi_entry_group_reset(group);
162
163    create_services(c);
164    return;
165
166fail:
167    avahi_simple_poll_quit(simple_poll);
168}
169
170static void client_callback(AvahiClient *c, AvahiClientState state, AVAHI_GCC_UNUSED void * userdata) {
171    assert(c);
172
173    /* Called whenever the client or server state changes */
174
175    switch (state) {
176        case AVAHI_CLIENT_S_RUNNING:
177
178            /* The server has startup successfully and registered its host
179             * name on the network, so it's time to create our services */
180            create_services(c);
181            break;
182
183        case AVAHI_CLIENT_FAILURE:
184
185            fprintf(stderr, "Client failure: %s\n", avahi_strerror(avahi_client_errno(c)));
186            avahi_simple_poll_quit(simple_poll);
187
188            break;
189
190        case AVAHI_CLIENT_S_COLLISION:
191
192            /* Let's drop our registered services. When the server is back
193             * in AVAHI_SERVER_RUNNING state we will register them
194             * again with the new host name. */
195
196        case AVAHI_CLIENT_S_REGISTERING:
197
198            /* The server records are now being established. This
199             * might be caused by a host name change. We need to wait
200             * for our own records to register until the host name is
201             * properly esatblished. */
202
203            if (group)
204                avahi_entry_group_reset(group);
205
206            break;
207
208        case AVAHI_CLIENT_CONNECTING:
209            ;
210    }
211}
212
213static void modify_callback(AVAHI_GCC_UNUSED AvahiTimeout *e, void *userdata) {
214    AvahiClient *client = userdata;
215
216    fprintf(stderr, "Doing some weird modification\n");
217
218    avahi_free(name);
219    name = avahi_strdup("Modified MegaPrinter");
220
221    /* If the server is currently running, we need to remove our
222     * service and create it anew */
223    if (avahi_client_get_state(client) == AVAHI_CLIENT_S_RUNNING) {
224
225        /* Remove the old services */
226        if (group)
227            avahi_entry_group_reset(group);
228
229        /* And create them again with the new name */
230        create_services(client);
231    }
232}
233
234int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
235    AvahiClient *client = NULL;
236    int error;
237    int ret = 1;
238    struct timeval tv;
239
240    /* Allocate main loop object */
241    if (!(simple_poll = avahi_simple_poll_new())) {
242        fprintf(stderr, "Failed to create simple poll object.\n");
243        goto fail;
244    }
245
246    name = avahi_strdup("MegaPrinter");
247
248    /* Allocate a new client */
249    client = avahi_client_new(avahi_simple_poll_get(simple_poll), 0, client_callback, NULL, &error);
250
251    /* Check wether creating the client object succeeded */
252    if (!client) {
253        fprintf(stderr, "Failed to create client: %s\n", avahi_strerror(error));
254        goto fail;
255    }
256
257    /* After 10s do some weird modification to the service */
258    avahi_simple_poll_get(simple_poll)->timeout_new(
259        avahi_simple_poll_get(simple_poll),
260        avahi_elapse_time(&tv, 1000*10, 0),
261        modify_callback,
262        client);
263
264    /* Run the main loop */
265    avahi_simple_poll_loop(simple_poll);
266
267    ret = 0;
268
269fail:
270
271    /* Cleanup things */
272
273    if (client)
274        avahi_client_free(client);
275
276    if (simple_poll)
277        avahi_simple_poll_free(simple_poll);
278
279    avahi_free(name);
280
281    return ret;
282}
283