1 /*****************************************************************************
2 * netsync.c: synchronisation between several network clients.
3 *****************************************************************************
4 * Copyright (C) 2004 the VideoLAN team
7 * Authors: Gildas Bazin <gbazin@videolan.org>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22 *****************************************************************************/
24 /*****************************************************************************
26 *****************************************************************************/
31 #include <vlc_common.h>
32 #include <vlc_plugin.h>
33 #include <vlc_interface.h>
34 #include <vlc_input.h>
35 #include <vlc_es_out.h>
40 #include <sys/types.h>
45 #include <vlc_network.h>
47 #define NETSYNC_PORT 9875
49 /* FIXME: UGLY UGLY !! Netsync should be totally reworked */
50 #include "../../src/input/input_internal.h"
52 /*****************************************************************************
54 *****************************************************************************/
55 static int Activate( vlc_object_t * );
56 static void Close ( vlc_object_t * );
58 static mtime_t GetClockRef( intf_thread_t *, mtime_t );
60 /// \bug [String] This string is BAD.
61 #define NETSYNC_TEXT N_( "Act as master" )
62 #define NETSYNC_LONGTEXT N_( "Should " \
63 "act as the master client for the network synchronisation?" )
65 /// \bug [String] This string is BAD.
66 #define MIP_TEXT N_( "Master client ip address" )
67 #define MIP_LONGTEXT N_( "IP address of " \
68 "the master client used for the network synchronisation." )
71 set_shortname( N_("Network Sync"))
72 set_description( N_("Network synchronisation") )
73 set_category( CAT_ADVANCED )
74 set_subcategory( SUBCAT_ADVANCED_MISC )
76 add_bool( "netsync-master", false, NULL,
77 NETSYNC_TEXT, NETSYNC_LONGTEXT, true )
78 add_string( "netsync-master-ip", NULL, NULL, MIP_TEXT, MIP_LONGTEXT,
81 set_capability( "interface", 0 )
82 set_callbacks( Activate, Close )
85 /*****************************************************************************
87 *****************************************************************************/
88 static void Run( intf_thread_t *p_intf );
90 /*****************************************************************************
91 * Activate: initialize and create stuff
92 *****************************************************************************/
93 static int Activate( vlc_object_t *p_this )
95 intf_thread_t *p_intf = (intf_thread_t*)p_this;
98 if( !var_InheritInteger( p_intf, "netsync-master" ) )
100 char *psz_master = var_InheritString( p_intf, "netsync-master-ip" );
101 if( psz_master == NULL )
103 msg_Err( p_intf, "master address not specified" );
106 fd = net_ConnectUDP( VLC_OBJECT(p_intf), psz_master, NETSYNC_PORT, -1 );
110 fd = net_ListenUDP1( VLC_OBJECT(p_intf), NULL, NETSYNC_PORT );
114 msg_Err( p_intf, "Netsync socket failure" );
118 p_intf->p_sys = (void *)(intptr_t)fd;
119 p_intf->pf_run = Run;
123 /*****************************************************************************
124 * Close: destroy interface
125 *****************************************************************************/
126 void Close( vlc_object_t *p_this )
128 intf_thread_t *p_intf = (intf_thread_t*)p_this;
130 net_Close( (intptr_t)p_intf->p_sys );
133 /*****************************************************************************
134 * Run: interface thread
135 *****************************************************************************/
136 static void Run( intf_thread_t *p_intf )
138 #define MAX_MSG_LENGTH (2 * sizeof(int64_t))
140 input_thread_t *p_input = NULL;
141 char p_data[MAX_MSG_LENGTH];
143 int canc = vlc_savecancel();
145 /* High priority thread */
146 vlc_thread_set_priority( p_intf, VLC_THREAD_PRIORITY_INPUT );
148 while( vlc_object_alive( p_intf ) )
150 /* Update the input */
151 if( p_input == NULL )
153 (input_thread_t *)vlc_object_find( p_intf, VLC_OBJECT_INPUT,
155 else if( p_input->b_dead )
157 vlc_object_release( p_input );
161 if( p_input == NULL )
164 msleep( INTF_IDLE_SLEEP );
169 * We now have an input
172 /* Initialize file descriptor set and timeout (0.5s) */
173 /* FIXME: arbitrary tick */
174 struct pollfd ufd = { .fd = i_socket, .events = POLLIN, };
178 struct sockaddr_storage from;
179 mtime_t i_date, i_clockref, i_master_clockref;
180 int i_struct_size, i_read, i_ret;
183 i_ret = poll( &ufd, 1, 500 );
184 if( i_ret == 0 ) continue;
188 msleep( INTF_IDLE_SLEEP );
192 /* We received something */
193 i_struct_size = sizeof( from );
194 i_read = recvfrom( i_socket, p_data, MAX_MSG_LENGTH, 0,
195 (struct sockaddr*)&from,
196 (unsigned int *)&i_struct_size );
198 i_clockref = ntoh64(*(int64_t *)p_data);
201 *(int64_t *)p_data = hton64( i_date );
203 i_master_clockref = GetClockRef( p_intf, i_clockref );
204 *(((int64_t *)p_data)+1) = hton64( i_master_clockref );
206 /* Reply to the sender */
207 sendto( i_socket, p_data, 2 * sizeof(int64_t), 0,
208 (struct sockaddr *)&from, i_struct_size );
211 msg_Dbg( p_intf, "Master clockref: %"PRId64" -> %"PRId64", from %s "
212 "(date: %"PRId64")", i_clockref, i_master_clockref,
213 from.ss_family == AF_INET
214 ? inet_ntoa(((struct sockaddr_in *)&from)->sin_addr)
215 : "non-IPv4", i_date );
220 mtime_t i_send_date, i_receive_date, i_master_date, i_diff_date;
221 mtime_t i_master_clockref, i_client_clockref, i_drift;
222 mtime_t i_clockref = 0;
223 int i_sent, i_read, i_ret;
225 /* Send clock request to the master */
226 *(int64_t *)p_data = hton64( i_clockref );
227 i_send_date = mdate();
229 i_sent = send( i_socket, p_data, sizeof(int64_t), 0 );
233 msleep( INTF_IDLE_SLEEP );
238 i_ret = poll( &ufd, 1, 500 );
239 if( i_ret == 0 ) continue;
243 msleep( INTF_IDLE_SLEEP );
247 i_receive_date = mdate();
249 i_read = recv( i_socket, p_data, MAX_MSG_LENGTH, 0 );
253 msleep( INTF_IDLE_SLEEP );
257 i_master_date = ntoh64(*(int64_t *)p_data);
258 i_master_clockref = ntoh64(*(((int64_t *)p_data)+1));
260 i_diff_date = i_receive_date -
261 ((i_receive_date - i_send_date) / 2 + i_master_date);
263 i_client_clockref = i_drift = 0;
264 if( p_input && i_master_clockref )
266 i_client_clockref = GetClockRef( p_intf, i_clockref );
267 i_drift = i_client_clockref - i_master_clockref - i_diff_date;
269 /* Update our clock to match the master's one */
270 if( i_client_clockref )
271 p_input->i_pts_delay -= i_drift;
275 msg_Dbg( p_intf, "Slave clockref: %"PRId64" -> %"PRId64" -> %"PRId64", "
276 "clock diff: %"PRId64" drift: %"PRId64,
277 i_clockref, i_master_clockref,
278 i_client_clockref, i_diff_date, i_drift );
282 msleep( INTF_IDLE_SLEEP );
286 if( p_input ) vlc_object_release( p_input );
287 vlc_restorecancel( canc );
290 static mtime_t GetClockRef( intf_thread_t *p_intf, mtime_t i_pts )
292 input_thread_t *p_input = p_intf->p_sys->p_input;
295 if( !p_input || !p_input->p->p_es_out ) return 0;
297 if( es_out_Control( p_input->p->p_es_out, ES_OUT_GET_TS, i_pts, &i_ts ) ==