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 #ifdef HAVE_SYS_TYPES_H
41 # include <sys/types.h>
47 #include <vlc_network.h>
49 #define NETSYNC_PORT 9875
51 /* FIXME: UGLY UGLY !! Netsync should be totally reworked */
52 #include "../../src/input/input_internal.h"
54 /*****************************************************************************
56 *****************************************************************************/
57 static int Activate( vlc_object_t * );
58 static void Close ( vlc_object_t * );
60 static mtime_t GetClockRef( intf_thread_t *, mtime_t );
62 /// \bug [String] This string is BAD.
63 #define NETSYNC_TEXT N_( "Act as master" )
64 #define NETSYNC_LONGTEXT N_( "Should " \
65 "act as the master client for the network synchronisation?" )
67 /// \bug [String] This string is BAD.
68 #define MIP_TEXT N_( "Master client ip address" )
69 #define MIP_LONGTEXT N_( "IP address of " \
70 "the master client used for the network synchronisation." )
73 set_shortname( N_("Network Sync"))
74 set_description( N_("Network synchronisation") )
75 set_category( CAT_ADVANCED )
76 set_subcategory( SUBCAT_ADVANCED_MISC )
78 add_bool( "netsync-master", false, NULL,
79 NETSYNC_TEXT, NETSYNC_LONGTEXT, true )
80 add_string( "netsync-master-ip", NULL, NULL, MIP_TEXT, MIP_LONGTEXT,
83 set_capability( "interface", 0 )
84 set_callbacks( Activate, Close )
87 /*****************************************************************************
89 *****************************************************************************/
90 static void Run( intf_thread_t *p_intf );
92 /*****************************************************************************
93 * Activate: initialize and create stuff
94 *****************************************************************************/
95 static int Activate( vlc_object_t *p_this )
97 intf_thread_t *p_intf = (intf_thread_t*)p_this;
100 if( !var_InheritInteger( p_intf, "netsync-master" ) )
102 char *psz_master = var_InheritString( p_intf, "netsync-master-ip" );
103 if( psz_master == NULL )
105 msg_Err( p_intf, "master address not specified" );
108 fd = net_ConnectUDP( VLC_OBJECT(p_intf), psz_master, NETSYNC_PORT, -1 );
112 fd = net_ListenUDP1( VLC_OBJECT(p_intf), NULL, NETSYNC_PORT );
116 msg_Err( p_intf, "Netsync socket failure" );
120 p_intf->p_sys = (void *)(intptr_t)fd;
121 p_intf->pf_run = Run;
125 /*****************************************************************************
126 * Close: destroy interface
127 *****************************************************************************/
128 void Close( vlc_object_t *p_this )
130 intf_thread_t *p_intf = (intf_thread_t*)p_this;
132 net_Close( (intptr_t)p_intf->p_sys );
135 /*****************************************************************************
136 * Run: interface thread
137 *****************************************************************************/
138 static void Run( intf_thread_t *p_intf )
140 #define MAX_MSG_LENGTH (2 * sizeof(int64_t))
142 input_thread_t *p_input = NULL;
143 char p_data[MAX_MSG_LENGTH];
145 int canc = vlc_savecancel();
147 /* High priority thread */
148 vlc_thread_set_priority( p_intf, VLC_THREAD_PRIORITY_INPUT );
150 while( vlc_object_alive( p_intf ) )
152 /* Update the input */
153 if( p_input == NULL )
155 (input_thread_t *)vlc_object_find( p_intf, VLC_OBJECT_INPUT,
157 else if( p_input->b_dead )
159 vlc_object_release( p_input );
163 if( p_input == NULL )
166 msleep( INTF_IDLE_SLEEP );
171 * We now have an input
174 /* Initialize file descriptor set and timeout (0.5s) */
175 /* FIXME: arbitrary tick */
176 struct pollfd ufd = { .fd = i_socket, .events = POLLIN, };
180 struct sockaddr_storage from;
181 mtime_t i_date, i_clockref, i_master_clockref;
182 int i_struct_size, i_read, i_ret;
185 i_ret = poll( &ufd, 1, 500 );
186 if( i_ret == 0 ) continue;
190 msleep( INTF_IDLE_SLEEP );
194 /* We received something */
195 i_struct_size = sizeof( from );
196 i_read = recvfrom( i_socket, p_data, MAX_MSG_LENGTH, 0,
197 (struct sockaddr*)&from,
198 (unsigned int *)&i_struct_size );
200 i_clockref = ntoh64(*(int64_t *)p_data);
203 *(int64_t *)p_data = hton64( i_date );
205 i_master_clockref = GetClockRef( p_intf, i_clockref );
206 *(((int64_t *)p_data)+1) = hton64( i_master_clockref );
208 /* Reply to the sender */
209 sendto( i_socket, p_data, 2 * sizeof(int64_t), 0,
210 (struct sockaddr *)&from, i_struct_size );
213 msg_Dbg( p_intf, "Master clockref: %"PRId64" -> %"PRId64", from %s "
214 "(date: %"PRId64")", i_clockref, i_master_clockref,
215 from.ss_family == AF_INET
216 ? inet_ntoa(((struct sockaddr_in *)&from)->sin_addr)
217 : "non-IPv4", i_date );
222 mtime_t i_send_date, i_receive_date, i_master_date, i_diff_date;
223 mtime_t i_master_clockref, i_client_clockref, i_drift;
224 mtime_t i_clockref = 0;
225 int i_sent, i_read, i_ret;
227 /* Send clock request to the master */
228 *(int64_t *)p_data = hton64( i_clockref );
229 i_send_date = mdate();
231 i_sent = send( i_socket, p_data, sizeof(int64_t), 0 );
235 msleep( INTF_IDLE_SLEEP );
240 i_ret = poll( &ufd, 1, 500 );
241 if( i_ret == 0 ) continue;
245 msleep( INTF_IDLE_SLEEP );
249 i_receive_date = mdate();
251 i_read = recv( i_socket, p_data, MAX_MSG_LENGTH, 0 );
255 msleep( INTF_IDLE_SLEEP );
259 i_master_date = ntoh64(*(int64_t *)p_data);
260 i_master_clockref = ntoh64(*(((int64_t *)p_data)+1));
262 i_diff_date = i_receive_date -
263 ((i_receive_date - i_send_date) / 2 + i_master_date);
265 i_client_clockref = i_drift = 0;
266 if( p_input && i_master_clockref )
268 i_client_clockref = GetClockRef( p_intf, i_clockref );
269 i_drift = i_client_clockref - i_master_clockref - i_diff_date;
271 /* Update our clock to match the master's one */
272 if( i_client_clockref )
273 p_input->i_pts_delay -= i_drift;
277 msg_Dbg( p_intf, "Slave clockref: %"PRId64" -> %"PRId64" -> %"PRId64", "
278 "clock diff: %"PRId64" drift: %"PRId64,
279 i_clockref, i_master_clockref,
280 i_client_clockref, i_diff_date, i_drift );
284 msleep( INTF_IDLE_SLEEP );
288 if( p_input ) vlc_object_release( p_input );
289 vlc_restorecancel( canc );
292 static mtime_t GetClockRef( intf_thread_t *p_intf, mtime_t i_pts )
294 input_thread_t *p_input = p_intf->p_sys->p_input;
297 if( !p_input || !p_input->p->p_es_out ) return 0;
299 if( es_out_Control( p_input->p->p_es_out, ES_OUT_GET_TS, i_pts, &i_ts ) ==