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         if ( global_properties )
 151                 return mlt_properties_set( global_properties, name, value );
 152         else
 153                 return -1;
 154 }
 155
 156 static void set_common_properties( mlt_properties properties, mlt_profile profile, const char *type, const char *service )
 157 {
 158         mlt_properties_set_int( properties, "_unique_id", ++ unique_id );
 159         mlt_properties_set( properties, "mlt_type", type );
 160         if ( mlt_properties_get_int( properties, "_mlt_service_hidden" ) == 0 )
 161                 mlt_properties_set( properties, "mlt_service", service );
 162         if ( profile != NULL )
 163                 mlt_properties_set_data( properties, "_profile", profile, 0, NULL, NULL );
 164 }
 165
 166 /** Fetch a producer from the repository.
 167 */
 168
 169 mlt_producer mlt_factory_producer( mlt_profile profile, const char *service, void *input )
 170 {
 171         mlt_producer obj = NULL;
 172
 173         // Pick up the default normalising producer if necessary
 174         if ( service == NULL )
 175                 service = mlt_environment( "MLT_PRODUCER" );
 176
 177         // Offer the application the chance to 'create'
 178         mlt_events_fire( event_object, "producer-create-request", service, input, &obj, NULL );
 179
 180         // Try to instantiate via the specified service
 181         if ( obj == NULL )
 182         {
 183                 obj = mlt_repository_fetch( producers, profile, producer_type, service, input );
 184                 mlt_events_fire( event_object, "producer-create-done", service, input, obj, NULL );
 185                 if ( obj != NULL )
 186                 {
 187                         mlt_properties properties = MLT_PRODUCER_PROPERTIES( obj );
 188                         set_common_properties( properties, profile, "producer", service );
 189                 }
 190         }
 191         return obj;
 192 }
 193
 194 /** Fetch a filter from the repository.
 195 */
 196
 197 mlt_filter mlt_factory_filter( mlt_profile profile, const char *service, void *input )
 198 {
 199         mlt_filter obj = NULL;
 200
 201         // Offer the application the chance to 'create'
 202         mlt_events_fire( event_object, "filter-create-request", service, input, &obj, NULL );
 203
 204         if ( obj == NULL )
 205         {
 206                 obj = mlt_repository_fetch( filters, profile, filter_type, service, input );
 207                 mlt_events_fire( event_object, "filter-create-done", service, input, obj, NULL );
 208         }
 209
 210         if ( obj != NULL )
 211         {
 212                 mlt_properties properties = MLT_FILTER_PROPERTIES( obj );
 213                 set_common_properties( properties, profile, "filter", service );
 214         }
 215         return obj;
 216 }
 217
 218 /** Fetch a transition from the repository.
 219 */
 220
 221 mlt_transition mlt_factory_transition( mlt_profile profile, const char *service, void *input )
 222 {
 223         mlt_transition obj = NULL;
 224
 225         // Offer the application the chance to 'create'
 226         mlt_events_fire( event_object, "transition-create-request", service, input, &obj, NULL );
 227
 228         if ( obj == NULL )
 229         {
 230                 obj = mlt_repository_fetch( transitions, profile, filter_type, service, input );
 231                 mlt_events_fire( event_object, "transition-create-done", service, input, obj, NULL );
 232         }
 233
 234         if ( obj != NULL )
 235         {
 236                 mlt_properties properties = MLT_TRANSITION_PROPERTIES( obj );
 237                 set_common_properties( properties, profile, "transition", service );
 238         }
 239         return obj;
 240 }
 241
 242 /** Fetch a consumer from the repository
 243 */
 244
 245 mlt_consumer mlt_factory_consumer( mlt_profile profile, const char *service, void *input )
 246 {
 247         mlt_consumer obj = NULL;
 248
 249         if ( service == NULL )
 250                 service = mlt_environment( "MLT_CONSUMER" );
 251
 252         // Offer the application the chance to 'create'
 253         mlt_events_fire( event_object, "consumer-create-request", service, input, &obj, NULL );
 254
 255         if ( obj == NULL )
 256         {
 257                 obj = mlt_repository_fetch( consumers, profile, consumer_type, service, input );
 258                 mlt_events_fire( event_object, "consumer-create-done", service, input, obj, NULL );
 259         }
 260
 261         if ( obj != NULL )
 262         {
 263                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( obj );
 264                 set_common_properties( properties, profile, "consumer", service );
 265         }
 266         return obj;
 267 }
 268
 269 /** Register an object for clean up.
 270 */
 271
 272 void mlt_factory_register_for_clean_up( void *ptr, mlt_destructor destructor )
 273 {
 274         char unique[ 256 ];
 275         sprintf( unique, "%08d", mlt_properties_count( global_properties ) );
 276         mlt_properties_set_data( global_properties, unique, ptr, 0, destructor, NULL );
 277 }
 278
 279 /** Close the factory.
 280 */
 281
 282 void mlt_factory_close( )
 283 {
 284         if ( mlt_prefix != NULL )
 285         {
 286                 mlt_properties_close( event_object );
 287                 mlt_repository_close( producers );
 288                 mlt_repository_close( filters );
 289                 mlt_repository_close( transitions );
 290                 mlt_repository_close( consumers );
 291                 mlt_properties_close( global_properties );
 292                 mlt_properties_close( object_list );
 293                 free( mlt_prefix );
 294                 mlt_prefix = NULL;
 295                 mlt_pool_close( );
 296         }
 297 }