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 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 #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( const 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
  94                 // Create the object list.
  95                 object_list = mlt_properties_new( );
  96
  97                 // Create a repository for each service type
  98                 producers = mlt_repository_init( object_list, prefix, "producers", "mlt_create_producer" );
  99                 filters = mlt_repository_init( object_list, prefix, "filters", "mlt_create_filter" );
 100                 transitions = mlt_repository_init( object_list, prefix, "transitions", "mlt_create_transition" );
 101                 consumers = mlt_repository_init( object_list, prefix, "consumers", "mlt_create_consumer" );
 102
 103                 // Force a clean up when app closes
 104                 atexit( mlt_factory_close );
 105         }
 106
 107         // Allow property refresh on a subsequent initialisation
 108         if ( global_properties != NULL )
 109         {
 110                 mlt_properties_set_or_default( global_properties, "MLT_NORMALISATION", getenv( "MLT_NORMALISATION" ), "PAL" );
 111                 mlt_properties_set_or_default( global_properties, "MLT_PRODUCER", getenv( "MLT_PRODUCER" ), "fezzik" );
 112                 mlt_properties_set_or_default( global_properties, "MLT_CONSUMER", getenv( "MLT_CONSUMER" ), "sdl" );
 113                 mlt_properties_set( global_properties, "MLT_TEST_CARD", getenv( "MLT_TEST_CARD" ) );
 114                 mlt_properties_set_or_default( global_properties, "MLT_PROFILE", getenv( "MLT_PROFILE" ), "dv_pal" );
 115         }
 116
 117
 118         return 0;
 119 }
 120
 121 /** Fetch the events object.
 122 */
 123
 124 mlt_properties mlt_factory_event_object( )
 125 {
 126         return event_object;
 127 }
 128
 129 /** Fetch the prefix used in this instance.
 130 */
 131
 132 const char *mlt_factory_prefix( )
 133 {
 134         return mlt_prefix;
 135 }
 136
 137 /** Get a value from the environment.
 138 */
 139
 140 char *mlt_environment( const char *name )
 141 {
 142         return mlt_properties_get( global_properties, name );
 143 }
 144
 145 /** Set a value in the environment.
 146 */
 147
 148 int mlt_environment_set( const char *name, const char *value )
 149 {
 150         return mlt_properties_set( global_properties, name, value );
 151 }
 152
 153 static void set_common_properties( mlt_properties properties, mlt_profile profile, const char *type, const char *service )
 154 {
 155         mlt_properties_set_int( properties, "_unique_id", ++ unique_id );
 156         mlt_properties_set( properties, "mlt_type", type );
 157         if ( mlt_properties_get_int( properties, "_mlt_service_hidden" ) == 0 )
 158                 mlt_properties_set( properties, "mlt_service", service );
 159         if ( profile != NULL )
 160                 mlt_properties_set_data( properties, "_profile", profile, 0, NULL, NULL );
 161 }
 162
 163 /** Fetch a producer from the repository.
 164 */
 165
 166 mlt_producer mlt_factory_producer( mlt_profile profile, const char *service, void *input )
 167 {
 168         mlt_producer obj = NULL;
 169
 170         // Pick up the default normalising producer if necessary
 171         if ( service == NULL )
 172                 service = mlt_environment( "MLT_PRODUCER" );
 173
 174         // Offer the application the chance to 'create'
 175         mlt_events_fire( event_object, "producer-create-request", service, input, &obj, NULL );
 176
 177         // Try to instantiate via the specified service
 178         if ( obj == NULL )
 179         {
 180                 obj = mlt_repository_fetch( producers, profile, producer_type, service, input );
 181                 mlt_events_fire( event_object, "producer-create-done", service, input, obj, NULL );
 182                 if ( obj != NULL )
 183                 {
 184                         mlt_properties properties = MLT_PRODUCER_PROPERTIES( obj );
 185                         set_common_properties( properties, profile, "producer", service );
 186                 }
 187         }
 188         return obj;
 189 }
 190
 191 /** Fetch a filter from the repository.
 192 */
 193
 194 mlt_filter mlt_factory_filter( mlt_profile profile, const char *service, void *input )
 195 {
 196         mlt_filter obj = NULL;
 197
 198         // Offer the application the chance to 'create'
 199         mlt_events_fire( event_object, "filter-create-request", service, input, &obj, NULL );
 200
 201         if ( obj == NULL )
 202         {
 203                 obj = mlt_repository_fetch( filters, profile, filter_type, service, input );
 204                 mlt_events_fire( event_object, "filter-create-done", service, input, obj, NULL );
 205         }
 206
 207         if ( obj != NULL )
 208         {
 209                 mlt_properties properties = MLT_FILTER_PROPERTIES( obj );
 210                 set_common_properties( properties, profile, "filter", service );
 211         }
 212         return obj;
 213 }
 214
 215 /** Fetch a transition from the repository.
 216 */
 217
 218 mlt_transition mlt_factory_transition( mlt_profile profile, const char *service, void *input )
 219 {
 220         mlt_transition obj = NULL;
 221
 222         // Offer the application the chance to 'create'
 223         mlt_events_fire( event_object, "transition-create-request", service, input, &obj, NULL );
 224
 225         if ( obj == NULL )
 226         {
 227                 obj = mlt_repository_fetch( transitions, profile, filter_type, service, input );
 228                 mlt_events_fire( event_object, "transition-create-done", service, input, obj, NULL );
 229         }
 230
 231         if ( obj != NULL )
 232         {
 233                 mlt_properties properties = MLT_TRANSITION_PROPERTIES( obj );
 234                 set_common_properties( properties, profile, "transition", service );
 235         }
 236         return obj;
 237 }
 238
 239 /** Fetch a consumer from the repository
 240 */
 241
 242 mlt_consumer mlt_factory_consumer( mlt_profile profile, const char *service, void *input )
 243 {
 244         mlt_consumer obj = NULL;
 245
 246         if ( service == NULL )
 247                 service = mlt_environment( "MLT_CONSUMER" );
 248
 249         // Offer the application the chance to 'create'
 250         mlt_events_fire( event_object, "consumer-create-request", service, input, &obj, NULL );
 251
 252         if ( obj == NULL )
 253         {
 254                 obj = mlt_repository_fetch( consumers, profile, consumer_type, service, input );
 255                 mlt_events_fire( event_object, "consumer-create-done", service, input, obj, NULL );
 256         }
 257
 258         if ( obj != NULL )
 259         {
 260                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( obj );
 261                 set_common_properties( properties, profile, "consumer", service );
 262         }
 263         return obj;
 264 }
 265
 266 /** Register an object for clean up.
 267 */
 268
 269 void mlt_factory_register_for_clean_up( void *ptr, mlt_destructor destructor )
 270 {
 271         char unique[ 256 ];
 272         sprintf( unique, "%08d", mlt_properties_count( global_properties ) );
 273         mlt_properties_set_data( global_properties, unique, ptr, 0, destructor, NULL );
 274 }
 275
 276 /** Close the factory.
 277 */
 278
 279 void mlt_factory_close( )
 280 {
 281         if ( mlt_prefix != NULL )
 282         {
 283                 mlt_properties_close( event_object );
 284                 mlt_repository_close( producers );
 285                 mlt_repository_close( filters );
 286                 mlt_repository_close( transitions );
 287                 mlt_repository_close( consumers );
 288                 mlt_properties_close( global_properties );
 289                 mlt_properties_close( object_list );
 290                 free( mlt_prefix );
 291                 mlt_prefix = NULL;
 292                 mlt_pool_close( );
 293         }
 294 }