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/*
* Copyright (C) 2012 Intel Corporation.
*
* Authors: Krzesimir Nowak <krnowak@openismus.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <gmodule.h>
#include "gupnp-dlna-metadata-backend.h"
#define GET_DEFAULT_EXTRACTOR_SYMBOL "gupnp_dlna_get_default_extractor"
struct {
GModule *module;
GUPnPDLNAMetadataExtractor * (* get_default_extractor) (void);
} metadata_backend;
static gboolean
load_metadata_backend (void)
{
static gsize backend_chosen = 0;
if (g_once_init_enter (&backend_chosen)) {
gchar **environment = g_get_environ ();
const gchar *backend =
g_environ_getenv (environment,
"GUPNP_DLNA_METADATA_BACKEND");
const gchar *backend_dir =
g_environ_getenv (environment,
"GUPNP_DLNA_METADATA_BACKEND_DIR");
GModule *module;
gchar *module_path;
gpointer get_default_extractor = NULL;
gsize loaded = 1;
if (!backend)
backend = GUPNP_DLNA_DEFAULT_METADATA_BACKEND;
if (!backend_dir)
backend_dir = GUPNP_DLNA_DEFAULT_METADATA_BACKEND_DIR;
module_path = g_module_build_path (backend_dir, backend);
module = g_module_open (module_path, G_MODULE_BIND_MASK);
if (!module) {
g_warning ("Could not load open metadata backend '%s'.",
module_path);
goto fail;
}
if (!g_module_symbol (module,
GET_DEFAULT_EXTRACTOR_SYMBOL,
&get_default_extractor)) {
g_warning ("Could not find '"
GET_DEFAULT_EXTRACTOR_SYMBOL
"' symbol in '%s'.",
module_path);
goto fail;
}
if (!get_default_extractor) {
g_warning ("'"
GET_DEFAULT_EXTRACTOR_SYMBOL
"' symbol in '%s' is invalid.",
module_path);
goto fail;
}
g_module_make_resident (module);
metadata_backend.module = module;
metadata_backend.get_default_extractor = get_default_extractor;
module = NULL;
loaded = 2;
fail:
g_free (module_path);
if (module)
g_module_close (module);
g_strfreev (environment);
g_once_init_leave (&backend_chosen, loaded);
}
return (backend_chosen == 2);
}
GUPnPDLNAMetadataExtractor *
gupnp_dlna_metadata_backend_get_extractor (void)
{
gboolean metadata_backend_loaded = load_metadata_backend ();
g_return_val_if_fail (metadata_backend_loaded == TRUE, NULL);
return metadata_backend.get_default_extractor ();
}
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