/***
This file is part of avahi.
avahi is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of the
License, or (at your option) any later version.
avahi is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with avahi; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
USA.
***/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <time.h>
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <avahi-client/client.h>
#include <avahi-client/publish.h>
#include <avahi-common/alternative.h>
#include <avahi-common/simple-watch.h>
#include <avahi-common/malloc.h>
#include <avahi-common/error.h>
#include <avahi-common/timeval.h>
static AvahiEntryGroup *group = NULL;
static AvahiSimplePoll *simple_poll = NULL;
static char *name = NULL;
static void create_services(AvahiClient *c);
static void entry_group_callback(AvahiEntryGroup *g, AvahiEntryGroupState state, AVAHI_GCC_UNUSED void *userdata) {
assert(g == group || group == NULL);
group = g;
/* Called whenever the entry group state changes */
switch (state) {
case AVAHI_ENTRY_GROUP_ESTABLISHED :
/* The entry group has been established successfully */
fprintf(stderr, "Service '%s' successfully established.\n", name);
break;
case AVAHI_ENTRY_GROUP_COLLISION : {
char *n;
/* A service name collision with a remote service
* happened. Let's pick a new name */
n = avahi_alternative_service_name(name);
avahi_free(name);
name = n;
fprintf(stderr, "Service name collision, renaming service to '%s'\n", name);
/* And recreate the services */
create_services(avahi_entry_group_get_client(g));
break;
}
case AVAHI_ENTRY_GROUP_FAILURE :
fprintf(stderr, "Entry group failure: %s\n", avahi_strerror(avahi_client_errno(avahi_entry_group_get_client(g))));
/* Some kind of failure happened while we were registering our services */
avahi_simple_poll_quit(simple_poll);
break;
case AVAHI_ENTRY_GROUP_UNCOMMITED:
case AVAHI_ENTRY_GROUP_REGISTERING:
;
}
}
static void create_services(AvahiClient *c) {
char *n, r[128];
int ret;
assert(c);
/* If this is the first time we're called, let's create a new
* entry group if necessary */
if (!group)
if (!(group = avahi_entry_group_new(c, entry_group_callback, NULL))) {
fprintf(stderr, "avahi_entry_group_new() failed: %s\n", avahi_strerror(avahi_client_errno(c)));
goto fail;
}
/* If the group is empty (either because it was just created, or
* because it was reset previously, add our entries. */
if (avahi_entry_group_is_empty(group)) {
fprintf(stderr, "Adding service '%s'\n", name);
/* Create some random TXT data */
snprintf(r, sizeof(r), "random=%i", rand());
/* We will now add two services and one subtype to the entry
* group. The two services have the same name, but differ in
* the service type (IPP vs. BSD LPR). Only services with the
* same name should be put in the same entry group. */
/* Add the service for IPP */
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) {
if (ret == AVAHI_ERR_COLLISION)
goto collision;
fprintf(stderr, "Failed to add _ipp._tcp service: %s\n", avahi_strerror(ret));
goto fail;
}
/* Add the same service for BSD LPR */
if ((ret = avahi_entry_group_add_service(group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, 0, name, "_printer._tcp", NULL, NULL, 515, NULL)) < 0) {
if (ret == AVAHI_ERR_COLLISION)
goto collision;
fprintf(stderr, "Failed to add _printer._tcp service: %s\n", avahi_strerror(ret));
goto fail;
}
/* Add an additional (hypothetic) subtype */
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)) {
fprintf(stderr, "Failed to add subtype _magic._sub._printer._tcp: %s\n", avahi_strerror(ret));
goto fail;
}
/* Tell the server to register the service */
if ((ret = avahi_entry_group_commit(group)) < 0) {
fprintf(stderr, "Failed to commit entry group: %s\n", avahi_strerror(ret));
goto fail;
}
}
return;
collision:
/* A service name collision with a local service happened. Let's
* pick a new name */
n = avahi_alternative_service_name(name);
avahi_free(name);
name = n;
fprintf(stderr, "Service name collision, renaming service to '%s'\n", name);
avahi_entry_group_reset(group);
create_services(c);
return;
fail:
avahi_simple_poll_quit(simple_poll);
}
static void client_callback(AvahiClient *c, AvahiClientState state, AVAHI_GCC_UNUSED void * userdata) {
assert(c);
/* Called whenever the client or server state changes */
switch (state) {
case AVAHI_CLIENT_S_RUNNING:
/* The server has startup successfully and registered its host
* name on the network, so it's time to create our services */
create_services(c);
break;
case AVAHI_CLIENT_FAILURE:
fprintf(stderr, "Client failure: %s\n", avahi_strerror(avahi_client_errno(c)));
avahi_simple_poll_quit(simple_poll);
break;
case AVAHI_CLIENT_S_COLLISION:
/* Let's drop our registered services. When the server is back
* in AVAHI_SERVER_RUNNING state we will register them
* again with the new host name. */
case AVAHI_CLIENT_S_REGISTERING:
/* The server records are now being established. This
* might be caused by a host name change. We need to wait
* for our own records to register until the host name is
* properly esatblished. */
if (group)
avahi_entry_group_reset(group);
break;
case AVAHI_CLIENT_CONNECTING:
;
}
}
static void modify_callback(AVAHI_GCC_UNUSED AvahiTimeout *e, void *userdata) {
AvahiClient *client = userdata;
fprintf(stderr, "Doing some weird modification\n");
avahi_free(name);
name = avahi_strdup("Modified MegaPrinter");
/* If the server is currently running, we need to remove our
* service and create it anew */
if (avahi_client_get_state(client) == AVAHI_CLIENT_S_RUNNING) {
/* Remove the old services */
if (group)
avahi_entry_group_reset(group);
/* And create them again with the new name */
create_services(client);
}
}
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
AvahiClient *client = NULL;
int error;
int ret = 1;
struct timeval tv;
/* Allocate main loop object */
if (!(simple_poll = avahi_simple_poll_new())) {
fprintf(stderr, "Failed to create simple poll object.\n");
goto fail;
}
name = avahi_strdup("MegaPrinter");
/* Allocate a new client */
client = avahi_client_new(avahi_simple_poll_get(simple_poll), 0, client_callback, NULL, &error);
/* Check wether creating the client object succeeded */
if (!client) {
fprintf(stderr, "Failed to create client: %s\n", avahi_strerror(error));
goto fail;
}
/* After 10s do some weird modification to the service */
avahi_simple_poll_get(simple_poll)->timeout_new(
avahi_simple_poll_get(simple_poll),
avahi_elapse_time(&tv, 1000*10, 0),
modify_callback,
client);
/* Run the main loop */
avahi_simple_poll_loop(simple_poll);
ret = 0;
fail:
/* Cleanup things */
if (client)
avahi_client_free(client);
if (simple_poll)
avahi_simple_poll_free(simple_poll);
avahi_free(name);
return ret;
}