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/*
* Copyright (C) 2003-2014 The Music Player Daemon Project
* http://www.musicpd.org
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#include "ZeroconfAvahi.hxx"
#include "AvahiPoll.hxx"
#include "ZeroconfInternal.hxx"
#include "Listen.hxx"
#include "system/FatalError.hxx"
#include "util/Domain.hxx"
#include "Log.hxx"
#include <avahi-client/client.h>
#include <avahi-client/publish.h>
#include <avahi-common/alternative.h>
#include <avahi-common/domain.h>
#include <avahi-common/malloc.h>
#include <avahi-common/error.h>
#include <dbus/dbus.h>
static constexpr Domain avahi_domain("avahi");
static char *avahiName;
static MyAvahiPoll *avahi_poll;
static AvahiClient *avahiClient;
static AvahiEntryGroup *avahiGroup;
static void avahiRegisterService(AvahiClient * c);
/* Callback when the EntryGroup changes state */
static void avahiGroupCallback(AvahiEntryGroup * g,
AvahiEntryGroupState state,
gcc_unused void *userdata)
{
char *n;
assert(g);
FormatDebug(avahi_domain,
"Service group changed to state %d", state);
switch (state) {
case AVAHI_ENTRY_GROUP_ESTABLISHED:
/* The entry group has been established successfully */
FormatDefault(avahi_domain,
"Service '%s' successfully established.",
avahiName);
break;
case AVAHI_ENTRY_GROUP_COLLISION:
/* A service name collision happened. Let's pick a new name */
n = avahi_alternative_service_name(avahiName);
avahi_free(avahiName);
avahiName = n;
FormatDefault(avahi_domain,
"Service name collision, renaming service to '%s'",
avahiName);
/* And recreate the services */
avahiRegisterService(avahi_entry_group_get_client(g));
break;
case AVAHI_ENTRY_GROUP_FAILURE:
FormatError(avahi_domain,
"Entry group failure: %s",
avahi_strerror(avahi_client_errno
(avahi_entry_group_get_client(g))));
/* Some kind of failure happened while we were registering our services */
break;
case AVAHI_ENTRY_GROUP_UNCOMMITED:
LogDebug(avahi_domain, "Service group is UNCOMMITED");
break;
case AVAHI_ENTRY_GROUP_REGISTERING:
LogDebug(avahi_domain, "Service group is REGISTERING");
}
}
/* Registers a new service with avahi */
static void avahiRegisterService(AvahiClient * c)
{
FormatDebug(avahi_domain, "Registering service %s/%s",
SERVICE_TYPE, avahiName);
int ret;
assert(c);
/* If this is the first time we're called,
* let's create a new entry group */
if (!avahiGroup) {
avahiGroup = avahi_entry_group_new(c, avahiGroupCallback, nullptr);
if (!avahiGroup) {
FormatError(avahi_domain,
"Failed to create avahi EntryGroup: %s",
avahi_strerror(avahi_client_errno(c)));
goto fail;
}
}
/* Add the service */
/* TODO: This currently binds to ALL interfaces.
* We could maybe add a service per actual bound interface,
* if that's better. */
ret = avahi_entry_group_add_service(avahiGroup,
AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC,
AvahiPublishFlags(0),
avahiName, SERVICE_TYPE, nullptr,
nullptr, listen_port, nullptr);
if (ret < 0) {
FormatError(avahi_domain, "Failed to add service %s: %s",
SERVICE_TYPE, avahi_strerror(ret));
goto fail;
}
/* Tell the server to register the service group */
ret = avahi_entry_group_commit(avahiGroup);
if (ret < 0) {
FormatError(avahi_domain, "Failed to commit service group: %s",
avahi_strerror(ret));
goto fail;
}
return;
fail:
return;
}
/* Callback when avahi changes state */
static void avahiClientCallback(AvahiClient * c, AvahiClientState state,
gcc_unused void *userdata)
{
int reason;
assert(c);
/* Called whenever the client or server state changes */
FormatDebug(avahi_domain, "Client changed to state %d", state);
switch (state) {
case AVAHI_CLIENT_S_RUNNING:
LogDebug(avahi_domain, "Client is RUNNING");
/* The server has startup successfully and registered its host
* name on the network, so it's time to create our services */
if (!avahiGroup)
avahiRegisterService(c);
break;
case AVAHI_CLIENT_FAILURE:
reason = avahi_client_errno(c);
if (reason == AVAHI_ERR_DISCONNECTED) {
LogDefault(avahi_domain,
"Client Disconnected, will reconnect shortly");
if (avahiGroup) {
avahi_entry_group_free(avahiGroup);
avahiGroup = nullptr;
}
if (avahiClient)
avahi_client_free(avahiClient);
avahiClient =
avahi_client_new(avahi_poll,
AVAHI_CLIENT_NO_FAIL,
avahiClientCallback, nullptr,
&reason);
if (!avahiClient) {
FormatWarning(avahi_domain,
"Could not reconnect: %s",
avahi_strerror(reason));
}
} else {
FormatWarning(avahi_domain,
"Client failure: %s (terminal)",
avahi_strerror(reason));
}
break;
case AVAHI_CLIENT_S_COLLISION:
LogDebug(avahi_domain, "Client is 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. */
if (avahiGroup) {
LogDebug(avahi_domain, "Resetting group");
avahi_entry_group_reset(avahiGroup);
}
break;
case AVAHI_CLIENT_S_REGISTERING:
LogDebug(avahi_domain, "Client is 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 (avahiGroup) {
LogDebug(avahi_domain, "Resetting group");
avahi_entry_group_reset(avahiGroup);
}
break;
case AVAHI_CLIENT_CONNECTING:
LogDebug(avahi_domain, "Client is CONNECTING");
break;
}
}
void
AvahiInit(EventLoop &loop, const char *serviceName)
{
LogDebug(avahi_domain, "Initializing interface");
if (!avahi_is_valid_service_name(serviceName))
FormatFatalError("Invalid zeroconf_name \"%s\"", serviceName);
avahiName = avahi_strdup(serviceName);
avahi_poll = new MyAvahiPoll(loop);
int error;
avahiClient = avahi_client_new(avahi_poll, AVAHI_CLIENT_NO_FAIL,
avahiClientCallback, nullptr, &error);
if (!avahiClient) {
FormatError(avahi_domain, "Failed to create client: %s",
avahi_strerror(error));
AvahiDeinit();
}
}
void
AvahiDeinit(void)
{
LogDebug(avahi_domain, "Shutting down interface");
if (avahiGroup) {
avahi_entry_group_free(avahiGroup);
avahiGroup = nullptr;
}
if (avahiClient) {
avahi_client_free(avahiClient);
avahiClient = nullptr;
}
delete avahi_poll;
avahi_poll = nullptr;
avahi_free(avahiName);
avahiName = nullptr;
dbus_shutdown();
}
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