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  *
   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 "mlt_repository.h"
  22 #include "mlt_properties.h"
  23
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <dlfcn.h>
  27 #include <string.h>
  28
  29 struct mlt_repository_s
  30 {
  31         struct mlt_properties_s parent; // a list of object files
  32         mlt_properties consumers; // lists of entry points
  33         mlt_properties filters;
  34         mlt_properties producers;
  35         mlt_properties transitions;
  36 };
  37
  38 mlt_repository mlt_repository_init( const char *prefix )
  39 {
  40         // Construct the repository
  41         mlt_repository this = calloc( sizeof( struct mlt_repository_s ), 1 );
  42         mlt_properties_init( &this->parent, this );
  43         this->consumers = mlt_properties_new();
  44         this->filters = mlt_properties_new();
  45         this->producers = mlt_properties_new();
  46         this->transitions = mlt_properties_new();
  47
  48         // Get the directory list
  49         mlt_properties dir = mlt_properties_new();
  50         int count = mlt_properties_dir_list( dir, prefix, NULL, 0 );
  51         int i;
  52
  53         // Iterate over files
  54         for ( i = 0; i < count; i++ )
  55         {
  56                 int flags = RTLD_NOW;
  57                 const char *object_name = mlt_properties_get_value( dir, i);
  58
  59                 // Very temporary hack to allow the quicktime plugins to work
  60                 // TODO: extend repository to allow this to be used on a case by case basis
  61                 if ( strstr( object_name, "libmltkino" ) )
  62                         flags |= RTLD_GLOBAL;
  63
  64                 // Open the shared object
  65                 void *object = dlopen( object_name, flags );
  66                 if ( object != NULL )
  67                 {
  68                         // Get the registration function
  69                         int ( *symbol_ptr )( mlt_repository ) = dlsym( object, "mlt_register" );
  70
  71                         // Call the registration function
  72                         if ( symbol_ptr != NULL )
  73                         {
  74                                 symbol_ptr( this );
  75
  76                                 // Register the object file for closure
  77                                 mlt_properties_set_data( &this->parent, object_name, object, 0, ( mlt_destructor )dlclose, NULL );
  78                         }
  79                         else
  80                         {
  81                                 dlclose( object );
  82                         }
  83                 }
  84         }
  85
  86         return this;
  87 }
  88
  89 void mlt_repository_register( mlt_repository this, mlt_service_type service_type, const char *service, void *symbol )
  90 {
  91         // Add the entry point to the corresponding service list
  92         switch ( service_type )
  93         {
  94                 case consumer_type:
  95                         mlt_properties_set_data( this->consumers, service, symbol, 0, NULL, NULL );
  96                         break;
  97                 case filter_type:
  98                         mlt_properties_set_data( this->filters, service, symbol, 0, NULL, NULL );
  99                         break;
 100                 case producer_type:
 101                         mlt_properties_set_data( this->producers, service, symbol, 0, NULL, NULL );
 102                         break;
 103                 case transition_type:
 104                         mlt_properties_set_data( this->transitions, service, symbol, 0, NULL, NULL );
 105                         break;
 106                 default:
 107                         break;
 108         }
 109 }
 110
 111 void *mlt_repository_fetch( mlt_repository this, mlt_profile profile, mlt_service_type type, const char *service, void *input )
 112 {
 113         void *( *symbol_ptr )( mlt_profile, mlt_service_type, const char *, void * ) = NULL;
 114
 115         // Get the entry point from the corresponding service list
 116         switch ( type )
 117         {
 118                 case consumer_type:
 119                         symbol_ptr = mlt_properties_get_data( this->consumers, service, NULL );
 120                         break;
 121                 case filter_type:
 122                         symbol_ptr = mlt_properties_get_data( this->filters, service, NULL );
 123                         break;
 124                 case producer_type:
 125                         symbol_ptr = mlt_properties_get_data( this->producers, service, NULL );
 126                         break;
 127                 case transition_type:
 128                         symbol_ptr = mlt_properties_get_data( this->transitions, service, NULL );
 129                         break;
 130                 default:
 131                         break;
 132         }
 133
 134         // Construct the service
 135         return ( symbol_ptr != NULL ) ? symbol_ptr( profile, type, service, input ) : NULL;
 136 }
 137
 138 void mlt_repository_close( mlt_repository this )
 139 {
 140         mlt_properties_close( this->consumers );
 141         mlt_properties_close( this->filters );
 142         mlt_properties_close( this->producers );
 143         mlt_properties_close( this->transitions );
 144         mlt_properties_close( &this->parent );
 145         free( this );
 146 }