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

   1 /*
   2  * repository.c -- provides a map between service and shared objects
   3  * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
   4  * Author: Charles Yates <charles.yates@pandora.be>
   5  * Contributor: Dan Dennedy <dan@dennedy.org>
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #include "mlt_repository.h"
  23 #include "mlt_properties.h"
  24 #include "mlt_tokeniser.h"
  25
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <dlfcn.h>
  29 #include <string.h>
  30
  31 struct mlt_repository_s
  32 {
  33         struct mlt_properties_s parent; // a list of object files
  34         mlt_properties consumers; // lists of entry points
  35         mlt_properties filters;
  36         mlt_properties producers;
  37         mlt_properties transitions;
  38 };
  39
  40 /** Construct a new repository
  41 */
  42
  43 mlt_repository mlt_repository_init( const char *directory )
  44 {
  45         // Safety check
  46         if ( directory == NULL || strcmp( directory, "" ) == 0 )
  47                 return NULL;
  48
  49         // Construct the repository
  50         mlt_repository this = calloc( sizeof( struct mlt_repository_s ), 1 );
  51         mlt_properties_init( &this->parent, this );
  52         this->consumers = mlt_properties_new();
  53         this->filters = mlt_properties_new();
  54         this->producers = mlt_properties_new();
  55         this->transitions = mlt_properties_new();
  56
  57         // Get the directory list
  58         mlt_properties dir = mlt_properties_new();
  59         int count = mlt_properties_dir_list( dir, directory, NULL, 0 );
  60         int i;
  61
  62         // Iterate over files
  63         for ( i = 0; i < count; i++ )
  64         {
  65                 int flags = RTLD_NOW;
  66                 const char *object_name = mlt_properties_get_value( dir, i);
  67
  68                 // Very temporary hack to allow the quicktime plugins to work
  69                 // TODO: extend repository to allow this to be used on a case by case basis
  70                 if ( strstr( object_name, "libmltkino" ) )
  71                         flags |= RTLD_GLOBAL;
  72
  73                 // Open the shared object
  74                 void *object = dlopen( object_name, flags );
  75                 if ( object != NULL )
  76                 {
  77                         // Get the registration function
  78                         mlt_repository_callback symbol_ptr = dlsym( object, "mlt_register" );
  79
  80                         // Call the registration function
  81                         if ( symbol_ptr != NULL )
  82                         {
  83                                 symbol_ptr( this );
  84
  85                                 // Register the object file for closure
  86                                 mlt_properties_set_data( &this->parent, object_name, object, 0, ( mlt_destructor )dlclose, NULL );
  87                         }
  88                         else
  89                         {
  90                                 dlclose( object );
  91                         }
  92                 }
  93                 else if ( strstr( object_name, "libmlt" ) )
  94                 {
  95                         fprintf( stderr, "%s, %s: failed to dlopen %s\n", __FILE__, __FUNCTION__, object_name );
  96                 }
  97         }
  98
  99         return this;
 100 }
 101
 102 static mlt_properties new_service( void *symbol )
 103 {
 104         mlt_properties properties = mlt_properties_new();
 105         mlt_properties_set_data( properties, "symbol", symbol, 0, NULL, NULL );
 106         return properties;
 107 }
 108
 109 /** Register a service with the repository
 110     Typically, this is invoked by a module within its mlt_register().
 111 */
 112
 113 void mlt_repository_register( mlt_repository this, mlt_service_type service_type, const char *service, mlt_register_callback symbol )
 114 {
 115         // Add the entry point to the corresponding service list
 116         switch ( service_type )
 117         {
 118                 case consumer_type:
 119                         mlt_properties_set_data( this->consumers, service, new_service( symbol ), 0, ( mlt_destructor )mlt_properties_close, NULL );
 120                         break;
 121                 case filter_type:
 122                         mlt_properties_set_data( this->filters, service, new_service( symbol ), 0, ( mlt_destructor )mlt_properties_close, NULL );
 123                         break;
 124                 case producer_type:
 125                         mlt_properties_set_data( this->producers, service, new_service( symbol ), 0, ( mlt_destructor )mlt_properties_close, NULL );
 126                         break;
 127                 case transition_type:
 128                         mlt_properties_set_data( this->transitions, service, new_service( symbol ), 0, ( mlt_destructor )mlt_properties_close, NULL );
 129                         break;
 130                 default:
 131                         break;
 132         }
 133 }
 134
 135 static mlt_properties get_service_properties( mlt_repository this, mlt_service_type type, const char *service )
 136 {
 137         mlt_properties service_properties = NULL;
 138
 139         // Get the entry point from the corresponding service list
 140         switch ( type )
 141         {
 142                 case consumer_type:
 143                         service_properties = mlt_properties_get_data( this->consumers, service, NULL );
 144                         break;
 145                 case filter_type:
 146                         service_properties = mlt_properties_get_data( this->filters, service, NULL );
 147                         break;
 148                 case producer_type:
 149                         service_properties = mlt_properties_get_data( this->producers, service, NULL );
 150                         break;
 151                 case transition_type:
 152                         service_properties = mlt_properties_get_data( this->transitions, service, NULL );
 153                         break;
 154                 default:
 155                         break;
 156         }
 157         return service_properties;
 158 }
 159
 160 /** Construct a new instance of a service
 161 */
 162
 163 void *mlt_repository_create( mlt_repository this, mlt_profile profile, mlt_service_type type, const char *service, void *input )
 164 {
 165         mlt_properties properties = get_service_properties( this, type, service );
 166         if ( properties != NULL )
 167         {
 168                 mlt_register_callback symbol_ptr = mlt_properties_get_data( properties, "symbol", NULL );
 169
 170                 // Construct the service
 171                 return ( symbol_ptr != NULL ) ? symbol_ptr( profile, type, service, input ) : NULL;
 172         }
 173         return NULL;
 174 }
 175
 176 /** Destroy a repository
 177 */
 178
 179 void mlt_repository_close( mlt_repository this )
 180 {
 181         mlt_properties_close( this->consumers );
 182         mlt_properties_close( this->filters );
 183         mlt_properties_close( this->producers );
 184         mlt_properties_close( this->transitions );
 185         mlt_properties_close( &this->parent );
 186         free( this );
 187 }
 188
 189 /** Get the list of registered consumers
 190 */
 191
 192 mlt_properties mlt_repository_consumers( mlt_repository self )
 193 {
 194         return self->consumers;
 195 }
 196
 197 /** Get the list of registered filters
 198 */
 199
 200 mlt_properties mlt_repository_filters( mlt_repository self )
 201 {
 202         return self->filters;
 203 }
 204
 205 /** Get the list of registered producers
 206 */
 207
 208 mlt_properties mlt_repository_producers( mlt_repository self )
 209 {
 210         return self->producers;
 211 }
 212
 213 /** Get the list of registered transitions
 214 */
 215
 216 mlt_properties mlt_repository_transitions( mlt_repository self )
 217 {
 218         return self->transitions;
 219 }
 220
 221 /** Register the metadata for a service
 222     IMPORTANT: mlt_repository will take responsibility for deallocating the metadata properties that you supply!
 223 */
 224 void mlt_repository_register_metadata( mlt_repository self, mlt_service_type type, const char *service, mlt_metadata_callback callback, void *callback_data )
 225 {
 226         mlt_properties service_properties = get_service_properties( self, type, service );
 227         mlt_properties_set_data( service_properties, "metadata_cb", callback, 0, NULL, NULL );
 228         mlt_properties_set_data( service_properties, "metadata_cb_data", callback_data, 0, NULL, NULL );
 229 }
 230
 231 /** Get the metadata about a service
 232     Returns NULL if service or its metadata are unavailable.
 233 */
 234
 235 mlt_properties mlt_repository_metadata( mlt_repository self, mlt_service_type type, const char *service )
 236 {
 237         mlt_properties metadata = NULL;
 238         mlt_properties properties = get_service_properties( self, type, service );
 239
 240         // If this is a valid service
 241         if ( properties )
 242         {
 243                 // Lookup cached metadata
 244                 metadata = mlt_properties_get_data( properties, "metadata", NULL );
 245                 if ( ! metadata )
 246                 {
 247                         // Not cached, so get the registered metadata callback function
 248                         mlt_metadata_callback callback = mlt_properties_get_data( properties, "metadata_cb", NULL );
 249
 250                         // If a metadata callback function is registered
 251                         if ( callback )
 252                         {
 253                                 // Fetch the callback data arg
 254                                 void *data = mlt_properties_get_data( properties, "metadata_cb_data", NULL );
 255
 256                                 // Fetch the metadata through the callback
 257                                 metadata = callback( type, service, data );
 258
 259                                 // Cache the metadata
 260                                 if ( metadata )
 261                                         // Include dellocation and serialisation
 262                                         mlt_properties_set_data( properties, "metadata", metadata, 0, ( mlt_destructor )mlt_properties_close, ( mlt_serialiser )mlt_properties_serialise_yaml );
 263                         }
 264                 }
 265         }
 266         return metadata;
 267 }
 268
 269 static const char *getenv_locale()
 270 {
 271         char *s = getenv( "LANGUAGE" );
 272         if ( s && s[0] )
 273                 return s;
 274         s = getenv( "LC_ALL" );
 275         if ( s && s[0] )
 276                 return s;
 277         s = getenv( "LC_MESSAGES" );
 278         if ( s && s[0] )
 279                 return s;
 280         s = getenv( "LANG" );
 281         if ( s && s[0] )
 282                 return s;
 283         return NULL;
 284 }
 285
 286 /** Return a list of user-preferred language codes taken from environment variables.
 287 */
 288
 289 mlt_properties mlt_repository_languages( mlt_repository self )
 290 {
 291         mlt_properties languages = mlt_properties_get_data( &self->parent, "languages", NULL );
 292         if ( languages )
 293                 return languages;
 294
 295         languages = mlt_properties_new();
 296         char *locale = getenv_locale();
 297         if ( locale )
 298         {
 299                 locale = strdup( locale );
 300                 mlt_tokeniser tokeniser = mlt_tokeniser_init();
 301                 int count = mlt_tokeniser_parse_new( tokeniser, locale, ":" );
 302                 if ( count )
 303                 {
 304                         int i;
 305                         for ( i = 0; i < count; i++ )
 306                         {
 307                                 char *locale = mlt_tokeniser_get_string( tokeniser, i );
 308                                 if ( strcmp( locale, "C" ) == 0 || strcmp( locale, "POSIX" ) == 0 )
 309                                         locale = "en";
 310                                 else if ( strlen( locale ) > 2 )
 311                                         locale[2] = 0;
 312                                 char string[21];
 313                                 snprintf( string, sizeof(string), "%d", i );
 314                                 mlt_properties_set( languages, string, locale );
 315                         }
 316                 }
 317                 else
 318                 {
 319                         mlt_properties_set( languages, "0", "en" );
 320                 }
 321                 free( locale );
 322                 mlt_tokeniser_close( tokeniser );
 323         }
 324         else
 325         {
 326                 mlt_properties_set( languages, "0", "en" );
 327         }
 328         mlt_properties_set_data( &self->parent, "languages", languages, 0, ( mlt_destructor )mlt_properties_close, NULL );
 329         return languages;
 330 }