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 *directory )
  39 {
  40         // Safety check
  41         if ( directory == NULL || strcmp( directory, "" ) == 0 )
  42                 return NULL;
  43
  44         // Construct the repository
  45         mlt_repository this = calloc( sizeof( struct mlt_repository_s ), 1 );
  46         mlt_properties_init( &this->parent, this );
  47         this->consumers = mlt_properties_new();
  48         this->filters = mlt_properties_new();
  49         this->producers = mlt_properties_new();
  50         this->transitions = mlt_properties_new();
  51
  52         // Get the directory list
  53         mlt_properties dir = mlt_properties_new();
  54         int count = mlt_properties_dir_list( dir, directory, NULL, 0 );
  55         int i;
  56
  57         // Iterate over files
  58         for ( i = 0; i < count; i++ )
  59         {
  60                 int flags = RTLD_NOW;
  61                 const char *object_name = mlt_properties_get_value( dir, i);
  62
  63                 // Very temporary hack to allow the quicktime plugins to work
  64                 // TODO: extend repository to allow this to be used on a case by case basis
  65                 if ( strstr( object_name, "libmltkino" ) )
  66                         flags |= RTLD_GLOBAL;
  67
  68                 // Open the shared object
  69                 void *object = dlopen( object_name, flags );
  70                 if ( object != NULL )
  71                 {
  72                         // Get the registration function
  73                         int ( *symbol_ptr )( mlt_repository ) = dlsym( object, "mlt_register" );
  74
  75                         // Call the registration function
  76                         if ( symbol_ptr != NULL )
  77                         {
  78                                 symbol_ptr( this );
  79
  80                                 // Register the object file for closure
  81                                 mlt_properties_set_data( &this->parent, object_name, object, 0, ( mlt_destructor )dlclose, NULL );
  82                         }
  83                         else
  84                         {
  85                                 dlclose( object );
  86                         }
  87                 }
  88         }
  89
  90         return this;
  91 }
  92
  93 void mlt_repository_register( mlt_repository this, mlt_service_type service_type, const char *service, void *symbol )
  94 {
  95         // Add the entry point to the corresponding service list
  96         switch ( service_type )
  97         {
  98                 case consumer_type:
  99                         mlt_properties_set_data( this->consumers, service, symbol, 0, NULL, NULL );
 100                         break;
 101                 case filter_type:
 102                         mlt_properties_set_data( this->filters, service, symbol, 0, NULL, NULL );
 103                         break;
 104                 case producer_type:
 105                         mlt_properties_set_data( this->producers, service, symbol, 0, NULL, NULL );
 106                         break;
 107                 case transition_type:
 108                         mlt_properties_set_data( this->transitions, service, symbol, 0, NULL, NULL );
 109                         break;
 110                 default:
 111                         break;
 112         }
 113 }
 114
 115 void *mlt_repository_create( mlt_repository this, mlt_profile profile, mlt_service_type type, const char *service, void *input )
 116 {
 117         void *( *symbol_ptr )( mlt_profile, mlt_service_type, const char *, void * ) = NULL;
 118
 119         // Get the entry point from the corresponding service list
 120         switch ( type )
 121         {
 122                 case consumer_type:
 123                         symbol_ptr = mlt_properties_get_data( this->consumers, service, NULL );
 124                         break;
 125                 case filter_type:
 126                         symbol_ptr = mlt_properties_get_data( this->filters, service, NULL );
 127                         break;
 128                 case producer_type:
 129                         symbol_ptr = mlt_properties_get_data( this->producers, service, NULL );
 130                         break;
 131                 case transition_type:
 132                         symbol_ptr = mlt_properties_get_data( this->transitions, service, NULL );
 133                         break;
 134                 default:
 135                         break;
 136         }
 137
 138         // Construct the service
 139         return ( symbol_ptr != NULL ) ? symbol_ptr( profile, type, service, input ) : NULL;
 140 }
 141
 142 void mlt_repository_close( mlt_repository this )
 143 {
 144         mlt_properties_close( this->consumers );
 145         mlt_properties_close( this->filters );
 146         mlt_properties_close( this->producers );
 147         mlt_properties_close( this->transitions );
 148         mlt_properties_close( &this->parent );
 149         free( this );
 150 }