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

   1 /**
   2  * \file mlt_repository.c
   3  * \brief provides a map between service and shared objects
   4  *
   5  * Copyright (C) 2003-2008 Ushodaya Enterprises Limited
   6  * \author Charles Yates <charles.yates@pandora.be>
   7  *         Dan Dennedy <dan@dennedy.org>
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2.1 of the License, or (at your option) any later version.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  22  */
  23
  24 #include "mlt_repository.h"
  25 #include "mlt_properties.h"
  26 #include "mlt_tokeniser.h"
  27 #include "mlt_log.h"
  28
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <dlfcn.h>
  32 #include <string.h>
  33
  34 /** \brief Repository class
  35  *
  36  * \extends mlt_properties_s
  37  */
  38
  39 struct mlt_repository_s
  40 {
  41         struct mlt_properties_s parent; // a list of object files
  42         mlt_properties consumers; // lists of entry points
  43         mlt_properties filters;
  44         mlt_properties producers;
  45         mlt_properties transitions;
  46 };
  47
  48 /** Construct a new repository
  49 */
  50
  51 mlt_repository mlt_repository_init( const char *directory )
  52 {
  53         // Safety check
  54         if ( directory == NULL || strcmp( directory, "" ) == 0 )
  55                 return NULL;
  56
  57         // Construct the repository
  58         mlt_repository this = calloc( sizeof( struct mlt_repository_s ), 1 );
  59         mlt_properties_init( &this->parent, this );
  60         this->consumers = mlt_properties_new();
  61         this->filters = mlt_properties_new();
  62         this->producers = mlt_properties_new();
  63         this->transitions = mlt_properties_new();
  64
  65         // Get the directory list
  66         mlt_properties dir = mlt_properties_new();
  67         int count = mlt_properties_dir_list( dir, directory, NULL, 0 );
  68         int i;
  69
  70         // Iterate over files
  71         for ( i = 0; i < count; i++ )
  72         {
  73                 int flags = RTLD_NOW;
  74                 const char *object_name = mlt_properties_get_value( dir, i);
  75
  76                 // Very temporary hack to allow the quicktime plugins to work
  77                 // TODO: extend repository to allow this to be used on a case by case basis
  78                 if ( strstr( object_name, "libmltkino" ) )
  79                         flags |= RTLD_GLOBAL;
  80
  81                 // Open the shared object
  82                 void *object = dlopen( object_name, flags );
  83                 if ( object != NULL )
  84                 {
  85                         // Get the registration function
  86                         mlt_repository_callback symbol_ptr = dlsym( object, "mlt_register" );
  87
  88                         // Call the registration function
  89                         if ( symbol_ptr != NULL )
  90                         {
  91                                 symbol_ptr( this );
  92
  93                                 // Register the object file for closure
  94                                 mlt_properties_set_data( &this->parent, object_name, object, 0, ( mlt_destructor )dlclose, NULL );
  95                         }
  96                         else
  97                         {
  98                                 dlclose( object );
  99                         }
 100                 }
 101                 else if ( strstr( object_name, "libmlt" ) )
 102                 {
 103                         mlt_log( NULL, MLT_LOG_WARNING, "%s: failed to dlopen %s\n  (%s)\n", __FUNCTION__, object_name, dlerror() );
 104                 }
 105         }
 106
 107         mlt_properties_close( dir );
 108
 109         return this;
 110 }
 111
 112 static mlt_properties new_service( void *symbol )
 113 {
 114         mlt_properties properties = mlt_properties_new();
 115         mlt_properties_set_data( properties, "symbol", symbol, 0, NULL, NULL );
 116         return properties;
 117 }
 118
 119 /** Register a service with the repository
 120     Typically, this is invoked by a module within its mlt_register().
 121 */
 122
 123 void mlt_repository_register( mlt_repository this, mlt_service_type service_type, const char *service, mlt_register_callback symbol )
 124 {
 125         // Add the entry point to the corresponding service list
 126         switch ( service_type )
 127         {
 128                 case consumer_type:
 129                         mlt_properties_set_data( this->consumers, service, new_service( symbol ), 0, ( mlt_destructor )mlt_properties_close, NULL );
 130                         break;
 131                 case filter_type:
 132                         mlt_properties_set_data( this->filters, service, new_service( symbol ), 0, ( mlt_destructor )mlt_properties_close, NULL );
 133                         break;
 134                 case producer_type:
 135                         mlt_properties_set_data( this->producers, service, new_service( symbol ), 0, ( mlt_destructor )mlt_properties_close, NULL );
 136                         break;
 137                 case transition_type:
 138                         mlt_properties_set_data( this->transitions, service, new_service( symbol ), 0, ( mlt_destructor )mlt_properties_close, NULL );
 139                         break;
 140                 default:
 141                         break;
 142         }
 143 }
 144
 145 static mlt_properties get_service_properties( mlt_repository this, mlt_service_type type, const char *service )
 146 {
 147         mlt_properties service_properties = NULL;
 148
 149         // Get the entry point from the corresponding service list
 150         switch ( type )
 151         {
 152                 case consumer_type:
 153                         service_properties = mlt_properties_get_data( this->consumers, service, NULL );
 154                         break;
 155                 case filter_type:
 156                         service_properties = mlt_properties_get_data( this->filters, service, NULL );
 157                         break;
 158                 case producer_type:
 159                         service_properties = mlt_properties_get_data( this->producers, service, NULL );
 160                         break;
 161                 case transition_type:
 162                         service_properties = mlt_properties_get_data( this->transitions, service, NULL );
 163                         break;
 164                 default:
 165                         break;
 166         }
 167         return service_properties;
 168 }
 169
 170 /** Construct a new instance of a service
 171 */
 172
 173 void *mlt_repository_create( mlt_repository this, mlt_profile profile, mlt_service_type type, const char *service, void *input )
 174 {
 175         mlt_properties properties = get_service_properties( this, type, service );
 176         if ( properties != NULL )
 177         {
 178                 mlt_register_callback symbol_ptr = mlt_properties_get_data( properties, "symbol", NULL );
 179
 180                 // Construct the service
 181                 return ( symbol_ptr != NULL ) ? symbol_ptr( profile, type, service, input ) : NULL;
 182         }
 183         return NULL;
 184 }
 185
 186 /** Destroy a repository
 187 */
 188
 189 void mlt_repository_close( mlt_repository this )
 190 {
 191         mlt_properties_close( this->consumers );
 192         mlt_properties_close( this->filters );
 193         mlt_properties_close( this->producers );
 194         mlt_properties_close( this->transitions );
 195         mlt_properties_close( &this->parent );
 196         free( this );
 197 }
 198
 199 /** Get the list of registered consumers
 200 */
 201
 202 mlt_properties mlt_repository_consumers( mlt_repository self )
 203 {
 204         return self->consumers;
 205 }
 206
 207 /** Get the list of registered filters
 208 */
 209
 210 mlt_properties mlt_repository_filters( mlt_repository self )
 211 {
 212         return self->filters;
 213 }
 214
 215 /** Get the list of registered producers
 216 */
 217
 218 mlt_properties mlt_repository_producers( mlt_repository self )
 219 {
 220         return self->producers;
 221 }
 222
 223 /** Get the list of registered transitions
 224 */
 225
 226 mlt_properties mlt_repository_transitions( mlt_repository self )
 227 {
 228         return self->transitions;
 229 }
 230
 231 /** Register the metadata for a service
 232     IMPORTANT: mlt_repository will take responsibility for deallocating the metadata properties that you supply!
 233 */
 234 void mlt_repository_register_metadata( mlt_repository self, mlt_service_type type, const char *service, mlt_metadata_callback callback, void *callback_data )
 235 {
 236         mlt_properties service_properties = get_service_properties( self, type, service );
 237         mlt_properties_set_data( service_properties, "metadata_cb", callback, 0, NULL, NULL );
 238         mlt_properties_set_data( service_properties, "metadata_cb_data", callback_data, 0, NULL, NULL );
 239 }
 240
 241 /** Get the metadata about a service
 242     Returns NULL if service or its metadata are unavailable.
 243 */
 244
 245 mlt_properties mlt_repository_metadata( mlt_repository self, mlt_service_type type, const char *service )
 246 {
 247         mlt_properties metadata = NULL;
 248         mlt_properties properties = get_service_properties( self, type, service );
 249
 250         // If this is a valid service
 251         if ( properties )
 252         {
 253                 // Lookup cached metadata
 254                 metadata = mlt_properties_get_data( properties, "metadata", NULL );
 255                 if ( ! metadata )
 256                 {
 257                         // Not cached, so get the registered metadata callback function
 258                         mlt_metadata_callback callback = mlt_properties_get_data( properties, "metadata_cb", NULL );
 259
 260                         // If a metadata callback function is registered
 261                         if ( callback )
 262                         {
 263                                 // Fetch the callback data arg
 264                                 void *data = mlt_properties_get_data( properties, "metadata_cb_data", NULL );
 265
 266                                 // Fetch the metadata through the callback
 267                                 metadata = callback( type, service, data );
 268
 269                                 // Cache the metadata
 270                                 if ( metadata )
 271                                         // Include dellocation and serialisation
 272                                         mlt_properties_set_data( properties, "metadata", metadata, 0, ( mlt_destructor )mlt_properties_close, ( mlt_serialiser )mlt_properties_serialise_yaml );
 273                         }
 274                 }
 275         }
 276         return metadata;
 277 }
 278
 279 static char *getenv_locale()
 280 {
 281         char *s = getenv( "LANGUAGE" );
 282         if ( s && s[0] )
 283                 return s;
 284         s = getenv( "LC_ALL" );
 285         if ( s && s[0] )
 286                 return s;
 287         s = getenv( "LC_MESSAGES" );
 288         if ( s && s[0] )
 289                 return s;
 290         s = getenv( "LANG" );
 291         if ( s && s[0] )
 292                 return s;
 293         return NULL;
 294 }
 295
 296 /** Return a list of user-preferred language codes taken from environment variables.
 297 */
 298
 299 mlt_properties mlt_repository_languages( mlt_repository self )
 300 {
 301         mlt_properties languages = mlt_properties_get_data( &self->parent, "languages", NULL );
 302         if ( languages )
 303                 return languages;
 304
 305         languages = mlt_properties_new();
 306         char *locale = getenv_locale();
 307         if ( locale )
 308         {
 309                 locale = strdup( locale );
 310                 mlt_tokeniser tokeniser = mlt_tokeniser_init();
 311                 int count = mlt_tokeniser_parse_new( tokeniser, locale, ":" );
 312                 if ( count )
 313                 {
 314                         int i;
 315                         for ( i = 0; i < count; i++ )
 316                         {
 317                                 char *locale = mlt_tokeniser_get_string( tokeniser, i );
 318                                 if ( strcmp( locale, "C" ) == 0 || strcmp( locale, "POSIX" ) == 0 )
 319                                         locale = "en";
 320                                 else if ( strlen( locale ) > 2 )
 321                                         locale[2] = 0;
 322                                 char string[21];
 323                                 snprintf( string, sizeof(string), "%d", i );
 324                                 mlt_properties_set( languages, string, locale );
 325                         }
 326                 }
 327                 else
 328                 {
 329                         mlt_properties_set( languages, "0", "en" );
 330                 }
 331                 free( locale );
 332                 mlt_tokeniser_close( tokeniser );
 333         }
 334         else
 335         {
 336                 mlt_properties_set( languages, "0", "en" );
 337         }
 338         mlt_properties_set_data( &self->parent, "languages", languages, 0, ( mlt_destructor )mlt_properties_close, NULL );
 339         return languages;
 340 }