hack to avoid dlopening a library that is already in the main app, by

2008-04-22  Havoc Pennington  <hp@pobox.com>

	* girepository/gmetadata.c (_g_metadata_init): hack to avoid
 	dlopening a library that is already in the main app, by checking
	whether one of the lib's symbols is already loaded.


svn path=/trunk/; revision=220
This commit is contained in:
Havoc Pennington 2008-04-23 01:17:24 +00:00 committed by Havoc Pennington
parent 0ed924f676
commit 81f5d90cd5

View File

@ -1749,6 +1749,43 @@ g_metadata_error_quark (void)
return quark;
}
static const char*
find_some_symbol (GMetadata *metadata)
{
Header *header = (Header *) metadata->data;
gint i;
for (i = 0; i < header->n_entries; i++)
{
DirEntry *entry;
entry = g_metadata_get_dir_entry (metadata, i + 1);
switch (entry->blob_type)
{
case BLOB_TYPE_FUNCTION:
{
FunctionBlob *blob = (FunctionBlob *) &metadata->data[entry->offset];
if (blob->symbol)
return g_metadata_get_string (metadata, blob->symbol);
}
break;
case BLOB_TYPE_OBJECT:
{
RegisteredTypeBlob *blob = (RegisteredTypeBlob *) &metadata->data[entry->offset];
if (blob->gtype_init)
return g_metadata_get_string (metadata, blob->gtype_init);
}
break;
default:
break;
}
}
return NULL;
}
static inline void
_g_metadata_init (GMetadata *metadata)
@ -1760,20 +1797,56 @@ _g_metadata_init (GMetadata *metadata)
{
const gchar *shlib;
/* Glade's autoconnect feature and OpenGL's extension mechanism
* as used by Clutter rely on dlopen(NULL) to work as a means of
* accessing the app's symbols. This keeps us from using
* G_MODULE_BIND_LOCAL. BIND_LOCAL may have other issues as well;
* in general libraries are not expecting multiple copies of
* themselves and are not expecting to be unloaded. So we just
* load modules globally for now.
*/
shlib = g_metadata_get_string (metadata, header->shared_library);
metadata->module = g_module_open (shlib, G_MODULE_BIND_LAZY);
/* note that NULL shlib means to open the main app, which is allowed */
/* If we do have a shared lib, first be sure the main app isn't already linked to it */
if (shlib != NULL)
{
const char *symbol_in_module;
symbol_in_module = find_some_symbol (metadata);
if (symbol_in_module != NULL)
{
metadata->module = g_module_open (NULL, G_MODULE_BIND_LAZY);
if (metadata->module == NULL)
{
g_warning ("Could not open main app as GModule: %s",
g_module_error ());
}
else
{
void *sym;
if (!g_module_symbol (metadata->module, symbol_in_module, &sym))
{
/* we will try opening the shlib, symbol is not in app already */
g_module_close (metadata->module);
metadata->module = NULL;
}
}
}
else
{
g_warning ("Could not find any symbols in metadata");
}
}
if (metadata->module == NULL)
g_warning ("Failed to load shared library referenced by the metadata: %s",
g_module_error ());
{
/* Glade's autoconnect feature and OpenGL's extension mechanism
* as used by Clutter rely on dlopen(NULL) to work as a means of
* accessing the app's symbols. This keeps us from using
* G_MODULE_BIND_LOCAL. BIND_LOCAL may have other issues as well;
* in general libraries are not expecting multiple copies of
* themselves and are not expecting to be unloaded. So we just
* load modules globally for now.
*/
metadata->module = g_module_open (shlib, G_MODULE_BIND_LAZY);
if (metadata->module == NULL)
g_warning ("Failed to load shared library referenced by the metadata: %s",
g_module_error ());
}
}
}