modules/access_output/srt.c

   1 /*****************************************************************************
   2  * srt.c: SRT (Secure Reliable Transport) output module
   3  *****************************************************************************
   4  * Copyright (C) 2017, Collabora Ltd.
   5  *
   6  * Authors: Justin Kim <justin.kim@collabora.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU Lesser General Public License as published by
  10  * the Free Software Foundation; either version 2.1 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this program; if not, write to the Free Software Foundation,
  20  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  21  *****************************************************************************/
  22
  23 #ifdef HAVE_CONFIG_H
  24 # include "config.h"
  25 #endif
  26
  27 #include <errno.h>
  28 #include <fcntl.h>
  29
  30 #include <vlc_common.h>
  31 #include <vlc_interrupt.h>
  32 #include <vlc_fs.h>
  33 #include <vlc_plugin.h>
  34 #include <vlc_sout.h>
  35 #include <vlc_block.h>
  36 #include <vlc_network.h>
  37
  38 #include <srt/srt.h>
  39
  40 /* libsrt defines default packet size as 1316 internally
  41  * so srt module takes same value. */
  42 #define SRT_DEFAULT_CHUNK_SIZE 1316
  43 /* libsrt tutorial uses 9000 as a default binding port */
  44 #define SRT_DEFAULT_PORT 9000
  45 /* The default timeout is -1 (infinite) */
  46 #define SRT_DEFAULT_POLL_TIMEOUT 100
  47 /* The default latency is 125
  48  * which uses srt library internally */
  49 #define SRT_DEFAULT_LATENCY 125
  50
  51 struct sout_access_out_sys_t
  52 {
  53     SRTSOCKET     sock;
  54     int           i_poll_id;
  55     int           i_poll_timeout;
  56     int           i_latency;
  57     size_t        i_chunk_size;
  58     int           i_pipe_fds[2];
  59 };
  60
  61 static void srt_wait_interrupted(void *p_data)
  62 {
  63     sout_access_out_t *p_access = p_data;
  64     sout_access_out_sys_t *p_sys = p_access->p_sys;
  65     msg_Dbg( p_access, "Waking up srt_epoll_wait");
  66     if ( write( p_sys->i_pipe_fds[1], &( bool ) { true }, sizeof( bool ) ) < 0 )
  67     {
  68         msg_Err( p_access, "Failed to send data to event fd");
  69     }
  70 }
  71
  72 static ssize_t Write( sout_access_out_t *p_access, block_t *p_buffer )
  73 {
  74     sout_access_out_sys_t *p_sys = p_access->p_sys;
  75     int i_len = 0;
  76
  77     vlc_interrupt_register( srt_wait_interrupted, p_access);
  78
  79     while( p_buffer )
  80     {
  81         block_t *p_next;
  82
  83         i_len += p_buffer->i_buffer;
  84
  85         while( p_buffer->i_buffer )
  86         {
  87             size_t i_write = __MIN( p_buffer->i_buffer, p_sys->i_chunk_size );
  88             SRTSOCKET ready[2];
  89
  90 retry:
  91             if ( srt_epoll_wait( p_sys->i_poll_id,
  92                 0, 0, ready, &(int){ 2 }, p_sys->i_poll_timeout,
  93                 &(int) { p_sys->i_pipe_fds[0] }, &(int) { 1 }, NULL, 0 ) == -1 )
  94             {
  95                 /* Assuming that timeout error is normal when SRT socket is connected. */
  96                 if ( srt_getlasterror( NULL ) == SRT_ETIMEOUT &&
  97                      srt_getsockstate( p_sys->sock ) == SRTS_CONNECTED )
  98                 {
  99                     srt_clearlasterror();
 100                     goto retry;
 101                 }
 102
 103                 i_len = VLC_EGENERIC;
 104                 goto out;
 105             }
 106
 107             bool cancel = 0;
 108             int ret = read( p_sys->i_pipe_fds[0], &cancel, sizeof( bool ) );
 109             if ( ret > 0 && cancel )
 110             {
 111                 msg_Dbg( p_access, "Cancelled running" );
 112                 i_len = 0;
 113                 goto out;
 114             }
 115
 116             if ( srt_sendmsg2( p_sys->sock, (char *)p_buffer->p_buffer, i_write, 0 ) == SRT_ERROR )
 117                 msg_Warn( p_access, "send error: %s", srt_getlasterror_str() );
 118
 119             p_buffer->p_buffer += i_write;
 120             p_buffer->i_buffer -= i_write;
 121         }
 122
 123         p_next = p_buffer->p_next;
 124         block_Release( p_buffer );
 125         p_buffer = p_next;
 126     }
 127
 128 out:
 129     vlc_interrupt_unregister();
 130     if ( i_len <= 0 ) block_ChainRelease( p_buffer );
 131     return i_len;
 132 }
 133
 134 static int Control( sout_access_out_t *p_access, int i_query, va_list args )
 135 {
 136     VLC_UNUSED (p_access);
 137
 138     int i_ret = VLC_SUCCESS;
 139
 140     switch( i_query )
 141     {
 142         case ACCESS_OUT_CONTROLS_PACE:
 143             *va_arg( args, bool * ) = false;
 144             break;
 145
 146         default:
 147             i_ret = VLC_EGENERIC;
 148             break;
 149     }
 150
 151     return i_ret;
 152 }
 153
 154 static int Open( vlc_object_t *p_this )
 155 {
 156     sout_access_out_t       *p_access = (sout_access_out_t*)p_this;
 157     sout_access_out_sys_t   *p_sys = NULL;
 158
 159     char                    *psz_dst_addr = NULL;
 160     int                      i_dst_port;
 161     int                      stat;
 162
 163     struct addrinfo hints = {
 164         .ai_socktype = SOCK_DGRAM,
 165     }, *res = NULL;
 166
 167     if (var_Create ( p_access, "dst-port", VLC_VAR_INTEGER )
 168      || var_Create ( p_access, "src-port", VLC_VAR_INTEGER )
 169      || var_Create ( p_access, "dst-addr", VLC_VAR_STRING )
 170      || var_Create ( p_access, "src-addr", VLC_VAR_STRING ) )
 171     {
 172          msg_Err( p_access, "Valid network information is required." );
 173         return VLC_ENOMEM;
 174     }
 175
 176     if( !( p_sys = malloc ( sizeof( *p_sys ) ) ) )
 177         return VLC_ENOMEM;
 178
 179     p_sys->i_chunk_size = var_InheritInteger( p_access, "chunk-size" );
 180     p_sys->i_poll_timeout = var_InheritInteger( p_access, "poll-timeout" );
 181     p_sys->i_latency = var_InheritInteger( p_access, "latency" );
 182     p_sys->i_poll_id = -1;
 183
 184     p_access->p_sys = p_sys;
 185
 186     i_dst_port = SRT_DEFAULT_PORT;
 187     char *psz_parser = psz_dst_addr = strdup( p_access->psz_path );
 188     if( !psz_dst_addr )
 189     {
 190         free( p_sys );
 191         return VLC_ENOMEM;
 192     }
 193
 194     if (psz_parser[0] == '[')
 195         psz_parser = strchr (psz_parser, ']');
 196
 197     psz_parser = strchr (psz_parser ? psz_parser : psz_dst_addr, ':');
 198     if (psz_parser != NULL)
 199     {
 200         *psz_parser++ = '\0';
 201         i_dst_port = atoi (psz_parser);
 202     }
 203
 204     msg_Dbg( p_access, "Setting SRT socket (dest addresss: %s, port: %d).",
 205              psz_dst_addr, i_dst_port );
 206
 207     stat = vlc_getaddrinfo( psz_dst_addr, i_dst_port, &hints, &res );
 208     if ( stat )
 209     {
 210         msg_Err( p_access, "Cannot resolve [%s]:%d (reason: %s)",
 211                  psz_dst_addr,
 212                  i_dst_port,
 213                  gai_strerror( stat ) );
 214
 215         goto failed;
 216     }
 217
 218     p_sys->sock = srt_socket( res->ai_family, SOCK_DGRAM, 0 );
 219     if ( p_sys->sock == SRT_ERROR )
 220     {
 221         msg_Err( p_access, "Failed to open socket." );
 222         goto failed;
 223     }
 224
 225     /* Make SRT non-blocking */
 226     srt_setsockopt( p_sys->sock, 0, SRTO_SNDSYN, &(bool) { false }, sizeof( bool ) );
 227
 228     /* Make sure TSBPD mode is enable (SRT mode) */
 229     srt_setsockopt( p_sys->sock, 0, SRTO_TSBPDMODE, &(int) { 1 }, sizeof( int ) );
 230
 231     /* This is an access_out so it is always a sender */
 232     srt_setsockopt( p_sys->sock, 0, SRTO_SENDER, &(int) { 1 }, sizeof( int ) );
 233
 234     /* Set latency */
 235     srt_setsockopt( p_sys->sock, 0, SRTO_TSBPDDELAY, &p_sys->i_latency, sizeof( int ) );
 236
 237     p_sys->i_poll_id = srt_epoll_create();
 238     if ( p_sys->i_poll_id == -1 )
 239     {
 240         msg_Err( p_access, "Failed to create poll id for SRT socket (reason: %s)",
 241                  srt_getlasterror_str() );
 242
 243         goto failed;
 244     }
 245
 246     if ( vlc_pipe( p_sys->i_pipe_fds ) != 0 )
 247     {
 248         msg_Err( p_access, "Failed to create pipe fds." );
 249         goto failed;
 250     }
 251     fcntl( p_sys->i_pipe_fds[0], F_SETFL, O_NONBLOCK | fcntl( p_sys->i_pipe_fds[0], F_GETFL ) );
 252
 253     srt_epoll_add_usock( p_sys->i_poll_id, p_sys->sock, &(int) { SRT_EPOLL_OUT });
 254     srt_setsockopt( p_sys->sock, 0, SRTO_SENDER, &(int) { 1 }, sizeof(int) );
 255
 256     srt_epoll_add_ssock( p_sys->i_poll_id, p_sys->i_pipe_fds[0], &(int) { SRT_EPOLL_IN } );
 257
 258     stat = srt_connect( p_sys->sock, res->ai_addr, sizeof (struct sockaddr));
 259     if ( stat == SRT_ERROR )
 260     {
 261         msg_Err( p_access, "Failed to connect to server (reason: %s)",
 262                  srt_getlasterror_str() );
 263         goto failed;
 264     }
 265
 266     p_access->pf_write = Write;
 267     p_access->pf_control = Control;
 268
 269     free( psz_dst_addr );
 270     freeaddrinfo( res );
 271
 272     return VLC_SUCCESS;
 273
 274 failed:
 275     if ( psz_dst_addr != NULL)
 276         free( psz_dst_addr );
 277
 278     if ( res != NULL )
 279         freeaddrinfo( res );
 280
 281     vlc_close( p_sys->i_pipe_fds[0] );
 282     vlc_close( p_sys->i_pipe_fds[1] );
 283
 284     if ( p_sys != NULL )
 285     {
 286         if ( p_sys->i_poll_id != -1 ) srt_epoll_release( p_sys->i_poll_id );
 287         if ( p_sys->sock != -1 ) srt_close( p_sys->sock );
 288
 289         free( p_sys );
 290     }
 291
 292     return VLC_EGENERIC;
 293 }
 294
 295 static void Close( vlc_object_t * p_this )
 296 {
 297     sout_access_out_t     *p_access = (sout_access_out_t*)p_this;
 298     sout_access_out_sys_t *p_sys = p_access->p_sys;
 299
 300     srt_epoll_release( p_sys->i_poll_id );
 301     srt_close( p_sys->sock );
 302
 303     vlc_close( p_sys->i_pipe_fds[0] );
 304     vlc_close( p_sys->i_pipe_fds[1] );
 305
 306     free( p_sys );
 307 }
 308
 309 /* Module descriptor */
 310 vlc_module_begin()
 311     set_shortname( N_("SRT") )
 312     set_description( N_("SRT stream output") )
 313     set_category( CAT_SOUT )
 314     set_subcategory( SUBCAT_SOUT_ACO )
 315
 316     add_integer( "chunk-size", SRT_DEFAULT_CHUNK_SIZE,
 317             N_("SRT chunk size (bytes)"), NULL, true )
 318     add_integer( "poll-timeout", SRT_DEFAULT_POLL_TIMEOUT,
 319             N_("Return poll wait after timeout miliseconds (-1 = infinite)"), NULL, true )
 320     add_integer( "latency", SRT_DEFAULT_LATENCY, N_("SRT latency (ms)"), NULL, true )
 321
 322     set_capability( "sout access", 0 )
 323     add_shortcut( "srt" )
 324
 325     set_callbacks( Open, Close )
 326 vlc_module_end ()