research.m1stereo.tv/gitweb/ - melted/blob - src/framework/mlt_factory.c

   1 /*
   2  * mlt_factory.c -- the factory method interfaces
   3  * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
   4  * Author: Charles Yates <charles.yates@pandora.be>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program 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
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 #include "config.h"
  22 #include "mlt.h"
  23 #include "mlt_repository.h"
  24
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28
  29 /** Singleton repositories
  30 */
  31
  32 static char *mlt_prefix = NULL;
  33 static mlt_properties global_properties = NULL;
  34 static mlt_properties object_list = NULL;
  35 static mlt_repository producers = NULL;
  36 static mlt_repository filters = NULL;
  37 static mlt_repository transitions = NULL;
  38 static mlt_repository consumers = NULL;
  39 static mlt_properties event_object = NULL;
  40 static int unique_id = 0;
  41
  42 /** Event transmitters.
  43 */
  44
  45 static void mlt_factory_create_request( mlt_listener listener, mlt_properties owner, mlt_service this, void **args )
  46 {
  47         if ( listener != NULL )
  48                 listener( owner, this, ( char * )args[ 0 ], ( char * )args[ 1 ], ( mlt_service * )args[ 2 ] );
  49 }
  50
  51 static void mlt_factory_create_done( mlt_listener listener, mlt_properties owner, mlt_service this, void **args )
  52 {
  53         if ( listener != NULL )
  54                 listener( owner, this, ( char * )args[ 0 ], ( char * )args[ 1 ], ( mlt_service )args[ 2 ] );
  55 }
  56
  57 /** Construct the factories.
  58 */
  59
  60 int mlt_factory_init( char *prefix )
  61 {
  62         // Only initialise once
  63         if ( mlt_prefix == NULL )
  64         {
  65                 // Allow user over rides
  66                 if ( prefix == NULL || !strcmp( prefix, "" ) )
  67                         prefix = getenv( "MLT_REPOSITORY" );
  68
  69                 // If no directory is specified, default to install directory
  70                 if ( prefix == NULL )
  71                         prefix = PREFIX_DATA;
  72
  73                 // Store the prefix for later retrieval
  74                 mlt_prefix = strdup( prefix );
  75
  76                 // Initialise the pool
  77                 mlt_pool_init( );
  78
  79                 // Create and set up the events object
  80                 event_object = mlt_properties_new( );
  81                 mlt_events_init( event_object );
  82                 mlt_events_register( event_object, "producer-create-request", ( mlt_transmitter )mlt_factory_create_request );
  83                 mlt_events_register( event_object, "producer-create-done", ( mlt_transmitter )mlt_factory_create_done );
  84                 mlt_events_register( event_object, "filter-create-request", ( mlt_transmitter )mlt_factory_create_request );
  85                 mlt_events_register( event_object, "filter-create-done", ( mlt_transmitter )mlt_factory_create_done );
  86                 mlt_events_register( event_object, "transition-create-request", ( mlt_transmitter )mlt_factory_create_request );
  87                 mlt_events_register( event_object, "transition-create-done", ( mlt_transmitter )mlt_factory_create_done );
  88                 mlt_events_register( event_object, "consumer-create-request", ( mlt_transmitter )mlt_factory_create_request );
  89                 mlt_events_register( event_object, "consumer-create-done", ( mlt_transmitter )mlt_factory_create_done );
  90
  91                 // Create the global properties
  92                 global_properties = mlt_properties_new( );
  93                 mlt_properties_set_or_default( global_properties, "MLT_NORMALISATION", getenv( "MLT_NORMALISATION" ), "PAL" );
  94                 mlt_properties_set_or_default( global_properties, "MLT_PRODUCER", getenv( "MLT_PRODUCER" ), "fezzik" );
  95                 mlt_properties_set_or_default( global_properties, "MLT_CONSUMER", getenv( "MLT_CONSUMER" ), "sdl" );
  96                 mlt_properties_set( global_properties, "MLT_TEST_CARD", getenv( "MLT_TEST_CARD" ) );
  97
  98                 // Create the object list.
  99                 object_list = mlt_properties_new( );
 100
 101                 // Create a repository for each service type
 102                 producers = mlt_repository_init( object_list, prefix, "producers", "mlt_create_producer" );
 103                 filters = mlt_repository_init( object_list, prefix, "filters", "mlt_create_filter" );
 104                 transitions = mlt_repository_init( object_list, prefix, "transitions", "mlt_create_transition" );
 105                 consumers = mlt_repository_init( object_list, prefix, "consumers", "mlt_create_consumer" );
 106
 107                 // Force a clean up when app closes
 108                 atexit( mlt_factory_close );
 109         }
 110
 111         return 0;
 112 }
 113
 114 /** Fetch the events object.
 115 */
 116
 117 mlt_properties mlt_factory_event_object( )
 118 {
 119         return event_object;
 120 }
 121
 122 /** Fetch the prefix used in this instance.
 123 */
 124
 125 const char *mlt_factory_prefix( )
 126 {
 127         return mlt_prefix;
 128 }
 129
 130 /** Get a value from the environment.
 131 */
 132
 133 char *mlt_environment( char *name )
 134 {
 135         return mlt_properties_get( global_properties, name );
 136 }
 137
 138 /** Fetch a producer from the repository.
 139 */
 140
 141 mlt_producer mlt_factory_producer( char *service, void *input )
 142 {
 143         mlt_producer obj = NULL;
 144
 145         // Pick up the default normalising producer if necessary
 146         if ( service == NULL )
 147                 service = mlt_environment( "MLT_PRODUCER" );
 148
 149         // Offer the application the chance to 'create'
 150         mlt_events_fire( event_object, "producer-create-request", service, input, &obj, NULL );
 151
 152         // Try to instantiate via the specified service
 153         if ( obj == NULL )
 154         {
 155                 obj = mlt_repository_fetch( producers, service, input );
 156                 mlt_events_fire( event_object, "producer-create-done", service, input, obj, NULL );
 157                 if ( obj != NULL )
 158                 {
 159                         mlt_properties properties = MLT_PRODUCER_PROPERTIES( obj );
 160                         mlt_properties_set_int( properties, "_unique_id", ++ unique_id );
 161                         mlt_properties_set( properties, "mlt_type", "producer" );
 162                         if ( mlt_properties_get_int( properties, "_mlt_service_hidden" ) == 0 )
 163                                 mlt_properties_set( properties, "mlt_service", service );
 164                 }
 165         }
 166         return obj;
 167 }
 168
 169 /** Fetch a filter from the repository.
 170 */
 171
 172 mlt_filter mlt_factory_filter( char *service, void *input )
 173 {
 174         mlt_filter obj = NULL;
 175
 176         // Offer the application the chance to 'create'
 177         mlt_events_fire( event_object, "filter-create-request", service, input, &obj, NULL );
 178
 179         if ( obj == NULL )
 180         {
 181                 obj = mlt_repository_fetch( filters, service, input );
 182                 mlt_events_fire( event_object, "filter-create-done", service, input, obj, NULL );
 183         }
 184
 185         if ( obj != NULL )
 186         {
 187                 mlt_properties properties = MLT_FILTER_PROPERTIES( obj );
 188                 mlt_properties_set_int( properties, "_unique_id", ++ unique_id );
 189                 mlt_properties_set( properties, "mlt_type", "filter" );
 190                 mlt_properties_set( properties, "mlt_service", service );
 191         }
 192         return obj;
 193 }
 194
 195 /** Fetch a transition from the repository.
 196 */
 197
 198 mlt_transition mlt_factory_transition( char *service, void *input )
 199 {
 200         mlt_transition obj = NULL;
 201
 202         // Offer the application the chance to 'create'
 203         mlt_events_fire( event_object, "transition-create-request", service, input, &obj, NULL );
 204
 205         if ( obj == NULL )
 206         {
 207                 obj = mlt_repository_fetch( transitions, service, input );
 208                 mlt_events_fire( event_object, "transition-create-done", service, input, obj, NULL );
 209         }
 210
 211         if ( obj != NULL )
 212         {
 213                 mlt_properties properties = MLT_TRANSITION_PROPERTIES( obj );
 214                 mlt_properties_set_int( properties, "_unique_id", ++ unique_id );
 215                 mlt_properties_set( properties, "mlt_type", "transition" );
 216                 mlt_properties_set( properties, "mlt_service", service );
 217         }
 218         return obj;
 219 }
 220
 221 /** Fetch a consumer from the repository
 222 */
 223
 224 mlt_consumer mlt_factory_consumer( char *service, void *input )
 225 {
 226         mlt_consumer obj = NULL;
 227
 228         if ( service == NULL )
 229                 service = mlt_environment( "MLT_CONSUMER" );
 230
 231         // Offer the application the chance to 'create'
 232         mlt_events_fire( event_object, "consumer-create-request", service, input, &obj, NULL );
 233
 234         if ( obj == NULL )
 235         {
 236                 obj = mlt_repository_fetch( consumers, service, input );
 237                 mlt_events_fire( event_object, "consumer-create-done", service, input, obj, NULL );
 238         }
 239
 240         if ( obj != NULL )
 241         {
 242                 mlt_filter filter = mlt_factory_filter( "data_show", NULL );
 243                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( obj );
 244                 mlt_properties_set_int( properties, "_unique_id", ++ unique_id );
 245                 mlt_properties_set( properties, "mlt_type", "consumer" );
 246                 mlt_properties_set( properties, "mlt_service", service );
 247                 mlt_service_attach( MLT_CONSUMER_SERVICE( obj ), filter );
 248                 mlt_filter_close( filter );
 249         }
 250         return obj;
 251 }
 252
 253 /** Register an object for clean up.
 254 */
 255
 256 void mlt_factory_register_for_clean_up( void *ptr, mlt_destructor destructor )
 257 {
 258         char unique[ 256 ];
 259         sprintf( unique, "%08d", mlt_properties_count( global_properties ) );
 260         mlt_properties_set_data( global_properties, unique, ptr, 0, destructor, NULL );
 261 }
 262
 263 /** Close the factory.
 264 */
 265
 266 void mlt_factory_close( )
 267 {
 268         if ( mlt_prefix != NULL )
 269         {
 270                 mlt_properties_close( event_object );
 271                 mlt_repository_close( producers );
 272                 mlt_repository_close( filters );
 273                 mlt_repository_close( transitions );
 274                 mlt_repository_close( consumers );
 275                 mlt_properties_close( global_properties );
 276                 mlt_properties_close( object_list );
 277                 free( mlt_prefix );
 278                 mlt_prefix = NULL;
 279                 mlt_pool_close( );
 280         }
 281 }
 282