research.m1stereo.tv/gitweb/ - melted/blob - src/modules/core/consumer_null.c

   1 /*
   2  * consumer_null.c -- a null consumer
   3  * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
   4  * Author: Charles Yates <charles.yates@pandora.be>
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 // mlt Header files
  22 #include <framework/mlt_consumer.h>
  23 #include <framework/mlt_frame.h>
  24
  25 // System header files
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <pthread.h>
  30
  31 // Forward references.
  32 static int consumer_start( mlt_consumer this );
  33 static int consumer_stop( mlt_consumer this );
  34 static int consumer_is_stopped( mlt_consumer this );
  35 static void *consumer_thread( void *arg );
  36 static void consumer_close( mlt_consumer this );
  37
  38 /** Initialise the dv consumer.
  39 */
  40
  41 mlt_consumer consumer_null_init( mlt_profile profile, mlt_service_type type, const char *id, char *arg )
  42 {
  43         // Allocate the consumer
  44         mlt_consumer this = mlt_consumer_new( profile );
  45
  46         // If memory allocated and initialises without error
  47         if ( this != NULL )
  48         {
  49                 // Assign close callback
  50                 this->close = consumer_close;
  51
  52                 // Set up start/stop/terminated callbacks
  53                 this->start = consumer_start;
  54                 this->stop = consumer_stop;
  55                 this->is_stopped = consumer_is_stopped;
  56         }
  57
  58         // Return this
  59         return this;
  60 }
  61
  62 /** Start the consumer.
  63 */
  64
  65 static int consumer_start( mlt_consumer this )
  66 {
  67         // Get the properties
  68         mlt_properties properties = MLT_CONSUMER_PROPERTIES( this );
  69
  70         // Check that we're not already running
  71         if ( !mlt_properties_get_int( properties, "running" ) )
  72         {
  73                 // Allocate a thread
  74                 pthread_t *thread = calloc( 1, sizeof( pthread_t ) );
  75
  76                 // Assign the thread to properties
  77                 mlt_properties_set_data( properties, "thread", thread, sizeof( pthread_t ), free, NULL );
  78
  79                 // Set the running state
  80                 mlt_properties_set_int( properties, "running", 1 );
  81                 mlt_properties_set_int( properties, "joined", 0 );
  82
  83                 // Create the thread
  84                 pthread_create( thread, NULL, consumer_thread, this );
  85         }
  86         return 0;
  87 }
  88
  89 /** Stop the consumer.
  90 */
  91
  92 static int consumer_stop( mlt_consumer this )
  93 {
  94         // Get the properties
  95         mlt_properties properties = MLT_CONSUMER_PROPERTIES( this );
  96
  97         // Check that we're running
  98         if ( !mlt_properties_get_int( properties, "joined" ) )
  99         {
 100                 // Get the thread
 101                 pthread_t *thread = mlt_properties_get_data( properties, "thread", NULL );
 102
 103                 // Stop the thread
 104                 mlt_properties_set_int( properties, "running", 0 );
 105                 mlt_properties_set_int( properties, "joined", 1 );
 106
 107                 // Wait for termination
 108                 pthread_join( *thread, NULL );
 109         }
 110
 111         return 0;
 112 }
 113
 114 /** Determine if the consumer is stopped.
 115 */
 116
 117 static int consumer_is_stopped( mlt_consumer this )
 118 {
 119         // Get the properties
 120         mlt_properties properties = MLT_CONSUMER_PROPERTIES( this );
 121         return !mlt_properties_get_int( properties, "running" );
 122 }
 123
 124 /** The main thread - the argument is simply the consumer.
 125 */
 126
 127 static void *consumer_thread( void *arg )
 128 {
 129         // Map the argument to the object
 130         mlt_consumer this = arg;
 131
 132         // Get the properties
 133         mlt_properties properties = MLT_CONSUMER_PROPERTIES( this );
 134
 135         // Convenience functionality
 136         int terminate_on_pause = mlt_properties_get_int( properties, "terminate_on_pause" );
 137         int terminated = 0;
 138
 139         // Frame and size
 140         mlt_frame frame = NULL;
 141
 142         // Loop while running
 143         while( !terminated && mlt_properties_get_int( properties, "running" ) )
 144         {
 145                 // Get the frame
 146                 frame = mlt_consumer_rt_frame( this );
 147
 148                 // Check for termination
 149                 if ( terminate_on_pause && frame != NULL )
 150                         terminated = mlt_properties_get_double( MLT_FRAME_PROPERTIES( frame ), "_speed" ) == 0.0;
 151
 152                 // Check that we have a frame to work with
 153                 if ( frame != NULL )
 154                 {
 155                         // Close the frame
 156                         mlt_events_fire( properties, "consumer-frame-show", frame, NULL );
 157                         mlt_frame_close( frame );
 158                 }
 159         }
 160
 161         // Indicate that the consumer is stopped
 162         mlt_properties_set_int( properties, "running", 0 );
 163         mlt_consumer_stopped( this );
 164
 165         return NULL;
 166 }
 167
 168 /** Close the consumer.
 169 */
 170
 171 static void consumer_close( mlt_consumer this )
 172 {
 173         // Stop the consumer
 174         mlt_consumer_stop( this );
 175
 176         // Close the parent
 177         mlt_consumer_close( this );
 178
 179         // Free the memory
 180         free( this );
 181 }