owntone-server/src/mdns_avahi.c

548 lines
11 KiB
C

/*
* Avahi mDNS backend, with libevent polling
*
* Copyright (C) 2009 Julien BLACHE <jb@jblache.org>
*
* Pieces coming from mt-daapd:
* Copyright (C) 2005 Sebastian Dröge <slomo@ubuntu.com>
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <event.h>
#include <avahi-common/watch.h>
#include <avahi-common/malloc.h>
#include <avahi-common/error.h>
#include <avahi-client/client.h>
#include <avahi-client/publish.h>
#include "daapd.h"
#include "err.h"
#include "mdns_avahi.h"
static AvahiClient *mdns_client = NULL;
static AvahiEntryGroup *mdns_group = NULL;
struct AvahiWatch
{
struct event ev;
AvahiWatchCallback cb;
void *userdata;
AvahiWatch *next;
};
struct AvahiTimeout
{
struct event ev;
AvahiTimeoutCallback cb;
void *userdata;
AvahiTimeout *next;
};
static AvahiWatch *all_w;
static AvahiTimeout *all_t;
/* libevent callbacks */
static void
evcb_watch(int fd, short ev_events, void *arg)
{
AvahiWatch *w;
AvahiWatchEvent a_events;
w = (AvahiWatch *)arg;
a_events = 0;
if (ev_events & EV_READ)
a_events |= AVAHI_WATCH_IN;
if (ev_events & EV_WRITE)
a_events |= AVAHI_WATCH_OUT;
event_add(&w->ev, NULL);
w->cb(w, fd, a_events, w->userdata);
}
static void
evcb_timeout(int fd, short ev_events, void *arg)
{
AvahiTimeout *t;
t = (AvahiTimeout *)arg;
t->cb(t, t->userdata);
}
/* AvahiPoll implementation for libevent */
static int
_ev_watch_add(AvahiWatch *w, int fd, AvahiWatchEvent a_events)
{
short ev_events;
ev_events = 0;
if (a_events & AVAHI_WATCH_IN)
ev_events |= EV_READ;
if (a_events & AVAHI_WATCH_OUT)
ev_events | EV_WRITE;
event_set(&w->ev, fd, ev_events, evcb_watch, w);
event_base_set(evbase_main, &w->ev);
return event_add(&w->ev, NULL);
}
static AvahiWatch *
ev_watch_new(const AvahiPoll *api, int fd, AvahiWatchEvent a_events, AvahiWatchCallback cb, void *userdata)
{
AvahiWatch *w;
int ret;
w = (AvahiWatch *)malloc(sizeof(AvahiWatch));
if (!w)
return NULL;
memset(w, 0, sizeof(AvahiWatch));
w->cb = cb;
w->userdata = userdata;
ret = _ev_watch_add(w, fd, a_events);
if (ret != 0)
{
free(w);
return NULL;
}
w->next = all_w;
all_w = w;
return w;
}
static void
ev_watch_update(AvahiWatch *w, AvahiWatchEvent a_events)
{
event_del(&w->ev);
_ev_watch_add(w, EVENT_FD(&w->ev), a_events);
}
static AvahiWatchEvent
ev_watch_get_events(AvahiWatch *w)
{
AvahiWatchEvent a_events;
a_events = 0;
if (event_pending(&w->ev, EV_READ, NULL))
a_events |= AVAHI_WATCH_IN;
if (event_pending(&w->ev, EV_WRITE, NULL))
a_events |= AVAHI_WATCH_OUT;
return a_events;
}
static void
ev_watch_free(AvahiWatch *w)
{
AvahiWatch *prev;
AvahiWatch *cur;
event_del(&w->ev);
prev = NULL;
for (cur = all_w; cur; prev = cur, cur = cur->next)
{
if (cur != w)
continue;
if (prev == NULL)
all_w = w->next;
else
prev->next = w->next;
break;
}
free(w);
}
static int
_ev_timeout_add(AvahiTimeout *t, const struct timeval *tv)
{
struct timeval e_tv;
struct timeval now;
int ret;
evtimer_set(&t->ev, evcb_timeout, t);
event_base_set(evbase_main, &t->ev);
if ((tv->tv_sec == 0) && (tv->tv_usec == 0))
{
evutil_timerclear(&e_tv);
}
else
{
ret = gettimeofday(&now, NULL);
if (ret != 0)
return -1;
evutil_timersub(tv, &now, &e_tv);
}
return evtimer_add(&t->ev, &e_tv);
}
static AvahiTimeout *
ev_timeout_new(const AvahiPoll *api, const struct timeval *tv, AvahiTimeoutCallback cb, void *userdata)
{
AvahiTimeout *t;
int ret;
t = (AvahiTimeout *)malloc(sizeof(AvahiTimeout));
if (!t)
return NULL;
memset(t, 0, sizeof(AvahiTimeout));
t->cb = cb;
t->userdata = userdata;
if (tv != NULL)
{
ret = _ev_timeout_add(t, tv);
if (ret != 0)
{
free(t);
return NULL;
}
}
t->next = all_t;
all_t = t;
return t;
}
static void
ev_timeout_update(AvahiTimeout *t, const struct timeval *tv)
{
event_del(&t->ev);
if (tv)
_ev_timeout_add(t, tv);
}
static void
ev_timeout_free(AvahiTimeout *t)
{
AvahiTimeout *prev;
AvahiTimeout *cur;
event_del(&t->ev);
prev = NULL;
for (cur = all_t; cur; prev = cur, cur = cur->next)
{
if (cur != t)
continue;
if (prev == NULL)
all_t = t->next;
else
prev->next = t->next;
break;
}
free(t);
}
static struct AvahiPoll ev_poll_api =
{
.userdata = NULL,
.watch_new = ev_watch_new,
.watch_update = ev_watch_update,
.watch_get_events = ev_watch_get_events,
.watch_free = ev_watch_free,
.timeout_new = ev_timeout_new,
.timeout_update = ev_timeout_update,
.timeout_free = ev_timeout_free
};
/* Avahi client callbacks & helpers (imported from mt-daapd) */
struct mdns_group_entry
{
char *name;
char *type;
int port;
AvahiStringList *txt;
struct mdns_group_entry *next;
};
static struct mdns_group_entry *group_entries;
static void
entry_group_callback(AvahiEntryGroup *g, AvahiEntryGroupState state, AVAHI_GCC_UNUSED void *userdata)
{
if (!g || (g != mdns_group))
return;
switch (state)
{
case AVAHI_ENTRY_GROUP_ESTABLISHED:
DPRINTF(E_DBG, L_REND, "Successfully added mDNS services\n");
break;
case AVAHI_ENTRY_GROUP_COLLISION:
DPRINTF(E_DBG, L_REND, "Group collision\n");
break;
case AVAHI_ENTRY_GROUP_FAILURE:
DPRINTF(E_DBG, L_REND, "Group failure\n");
break;
case AVAHI_ENTRY_GROUP_UNCOMMITED:
DPRINTF(E_DBG, L_REND, "Group uncommitted\n");
break;
case AVAHI_ENTRY_GROUP_REGISTERING:
DPRINTF(E_DBG, L_REND, "Group registering\n");
break;
}
}
static void
_create_services(void)
{
struct mdns_group_entry *pentry;
int ret;
DPRINTF(E_DBG, L_REND, "Creating service group\n");
if (!group_entries)
{
DPRINTF(E_DBG, L_REND, "No entries yet... skipping service create\n");
return;
}
if (mdns_group == NULL)
{
mdns_group = avahi_entry_group_new(mdns_client, entry_group_callback, NULL);
if (!mdns_group)
{
DPRINTF(E_WARN, L_REND, "Could not create Avahi EntryGroup: %s\n",
avahi_strerror(avahi_client_errno(mdns_client)));
return;
}
}
pentry = group_entries;
while (pentry)
{
DPRINTF(E_DBG, L_REND, "Re-registering %s/%s\n", pentry->name, pentry->type);
ret = avahi_entry_group_add_service_strlst(mdns_group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, 0,
avahi_strdup(pentry->name), avahi_strdup(pentry->type),
NULL, NULL, pentry->port, pentry->txt);
if (ret < 0)
{
DPRINTF(E_WARN, L_REND, "Could not add mDNS services: %s\n", avahi_strerror(ret));
return;
}
pentry = pentry->next;
}
ret = avahi_entry_group_commit(mdns_group);
if (ret < 0)
{
DPRINTF(E_WARN, L_REND, "Could not commit mDNS services: %s\n",
avahi_strerror(avahi_client_errno(mdns_client)));
}
}
static void
client_callback(AvahiClient *c, AvahiClientState state, AVAHI_GCC_UNUSED void * userdata)
{
int error;
switch (state)
{
case AVAHI_CLIENT_S_RUNNING:
DPRINTF(E_LOG, L_REND, "Avahi state change: Client running\n");
if (!mdns_group)
_create_services();
break;
case AVAHI_CLIENT_S_COLLISION:
DPRINTF(E_LOG, L_REND, "Avahi state change: Client collision\n");
if(mdns_group)
avahi_entry_group_reset(mdns_group);
break;
case AVAHI_CLIENT_FAILURE:
DPRINTF(E_LOG, L_REND, "Avahi state change: Client failure\n");
error = avahi_client_errno(c);
if (error == AVAHI_ERR_DISCONNECTED)
{
DPRINTF(E_LOG, L_REND, "Avahi Server disconnected, reconnecting\n");
avahi_client_free(mdns_client);
mdns_group = NULL;
mdns_client = avahi_client_new(&ev_poll_api, AVAHI_CLIENT_NO_FAIL,
client_callback, NULL, &error);
if (!mdns_client)
{
DPRINTF(E_LOG, L_REND, "Failed to create new Avahi client: %s\n",
avahi_strerror(error));
}
}
else
{
DPRINTF(E_LOG, L_REND, "Avahi client failure: %s\n", avahi_strerror(error));
}
break;
case AVAHI_CLIENT_S_REGISTERING:
DPRINTF(E_LOG, L_REND, "Avahi state change: Client registering\n");
if (mdns_group)
avahi_entry_group_reset(mdns_group);
break;
case AVAHI_CLIENT_CONNECTING:
DPRINTF(E_LOG, L_REND, "Avahi state change: Client connecting\n");
break;
}
}
/* mDNS interface - to be called only from the main thread */
int
mdns_init(void)
{
int error;
DPRINTF(E_DBG, L_REND, "Initializing Avahi mDNS\n");
all_w = NULL;
all_t = NULL;
group_entries = NULL;
mdns_client = avahi_client_new(&ev_poll_api, AVAHI_CLIENT_NO_FAIL,
client_callback, NULL, &error);
if (!mdns_client)
{
DPRINTF(E_WARN, L_REND, "mdns_init: Could not create Avahi client: %s\n",
avahi_strerror(avahi_client_errno(mdns_client)));
return -1;
}
return 0;
}
void
mdns_deinit(void)
{
struct mdns_group_entry *ge;
AvahiWatch *w;
AvahiTimeout *t;
for (t = all_t; t; t = t->next)
event_del(&t->ev);
for (w = all_w; w; w = w->next)
event_del(&w->ev);
for (ge = group_entries; ge; ge = ge->next)
{
group_entries = ge->next;
free(ge->name);
free(ge->type);
avahi_string_list_free(ge->txt);
free(ge);
}
if (mdns_client != NULL)
avahi_client_free(mdns_client);
}
int
mdns_register(char *name, char *type, int port, char **txt)
{
struct mdns_group_entry *ge;
AvahiStringList *txt_sl;
int i;
DPRINTF(E_DBG, L_REND, "Adding mDNS service %s/%s\n", name, type);
ge = (struct mdns_group_entry *)malloc(sizeof(struct mdns_group_entry));
if (!ge)
return -1;
ge->name = strdup(name);
ge->type = strdup(type);
ge->port = port;
txt_sl = NULL;
for (i = 0; txt[i]; i++)
{
txt_sl = avahi_string_list_add(txt_sl, txt[i]);
DPRINTF(E_DBG, L_REND, "Added key %s\n", txt[i]);
}
ge->txt = txt_sl;
ge->next = group_entries;
group_entries = ge;
if (mdns_group)
{
DPRINTF(E_DBG, L_MISC, "Resetting mDNS group\n");
avahi_entry_group_reset(mdns_group);
}
DPRINTF(E_DBG, L_REND, "Creating service group\n");
_create_services();
return 0;
}