luc14n0/glib
1
0
Fork 0
mirror of https://gitlab.gnome.org/GNOME/glib.git synced 2024-11-10 03:16:17 +01:00
Code Issues Packages Projects Releases Wiki Activity

[typelib] Clean up dlopen handling

Browse Source 
It's was busted that g_typelib_new_* does the dlopen() since that caused
g-ir-compiler to load the modules even though it wasn't going to do
anything with them.

Instead, change things so that g_module_symbol does the dlopen on-demand.
Remove the extra dlopen(NULL) inside girepository.c, we had another
already in gtypelib.c.

Thanks to Owen Taylor for suggesting this approach.
This commit is contained in:
Colin Walters 2009-08-18 10:23:09 -04:00
parent 90de854ee5
commit 1735ebde9a
3 changed files with 91 additions and 82 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
girepository.c
View File

@ -363,9 +363,6 @@ register_internal (GIRepository *repository,
g_hash_table_insert (repository->priv->typelibs, key, (void *)typelib);
}
if (typelib->modules == NULL)
typelib->modules = g_list_append(typelib->modules, g_module_open (NULL, 0));
return namespace;
}

169
gtypelib.c
View File

@ -1946,86 +1946,99 @@ g_typelib_error_quark (void)
return quark;
}
static inline void
_g_typelib_init (GTypelib *typelib)
static void
_g_typelib_do_dlopen (GTypelib *typelib)
{
Header *header;
const char *shlib_str;
header = (Header *) typelib->data;
/* note that NULL shlib means to open the main app, which is allowed */
if (header->shared_library)
shlib_str = g_typelib_get_string (typelib, header->shared_library);
else
shlib_str = NULL;
if (shlib_str != NULL && shlib_str[0] != '\0')
{
const gchar *shlib_str;
GModule *app_module = NULL;
gchar **shlibs;
gint i;
shlib_str = g_typelib_get_string (typelib, header->shared_library);
/* note that NULL shlib means to open the main app, which is allowed */
/* shared-library is a comma-separated list of libraries */
shlibs = g_strsplit (shlib_str, ",", 0);
if (shlib_str != NULL)
/* We load all passed libs unconditionally as if the same library is loaded
* again with dlopen(), the same file handle will be returned. See bug:
* http://bugzilla.gnome.org/show_bug.cgi?id=555294
*/
for (i = 0; shlibs[i]; i++)
{
gchar **shlibs;
gint i;
GModule *module;
/* shared-library is a comma-separated list of libraries */
shlibs = g_strsplit (shlib_str, ",", 0);
/* We load all passed libs unconditionally as if the same library is loaded
* again with dlopen(), the same file handle will be returned. See bug:
* http://bugzilla.gnome.org/show_bug.cgi?id=555294
/* 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.
*/
for (i = 0; shlibs[i]; i++)
module = g_module_open (shlibs[i], G_MODULE_BIND_LAZY);
if (module == NULL)
{
GModule *module;
GString *shlib_full = g_string_new (shlibs[i]);
/* 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.
*/
module = g_module_open (shlibs[i], G_MODULE_BIND_LAZY);
if (module == NULL)
{
GString *shlib_full = g_string_new (shlibs[i]);
/* Prefix with "lib", try both .la and .so */
if (!g_str_has_prefix (shlib_full->str, "lib"))
g_string_prepend (shlib_full, "lib");
g_string_append (shlib_full, ".la");
module = g_module_open (shlib_full->str, G_MODULE_BIND_LAZY);
if (module == NULL)
{
g_string_overwrite (shlib_full, strlen (shlib_full->str)-2, SHLIB_SUFFIX);
module = g_module_open (shlib_full->str, G_MODULE_BIND_LAZY);
}
g_string_free (shlib_full, TRUE);
}
if (module == NULL)
/* Prefix with "lib", try both .la and .so */
if (!g_str_has_prefix (shlib_full->str, "lib"))
g_string_prepend (shlib_full, "lib");
g_string_append (shlib_full, ".la");
module = g_module_open (shlib_full->str, G_MODULE_BIND_LAZY);
if (module == NULL)
{
g_warning ("Failed to load shared library '%s' referenced by the typelib: %s",
shlibs[i], g_module_error ());
g_string_overwrite (shlib_full, strlen (shlib_full->str)-2, SHLIB_SUFFIX);
module = g_module_open (shlib_full->str, G_MODULE_BIND_LAZY);
}
else
{
typelib->modules = g_list_append (typelib->modules, module);
}
}
g_strfreev (shlibs);
}
g_string_free (shlib_full, TRUE);
}
/* we should make sure the app_module in the end of list so that
* it's last symbol source when loading any symbols from modules.
* See comments in g_typelib_symbol */
app_module = g_module_open (NULL, G_MODULE_BIND_LAZY);
if (app_module)
typelib->modules = g_list_append (typelib->modules, app_module);
if (module == NULL)
{
g_warning ("Failed to load shared library '%s' referenced by the typelib: %s",
shlibs[i], g_module_error ());
}
else
{
typelib->modules = g_list_append (typelib->modules, module);
}
}
g_strfreev (shlibs);
}
else
{
/* If there's no shared-library entry for this module, assume that
* the module is for the application. Some of the hand-written .gir files
* in gobject-introspection don't have shared-library entries, but no one
* is really going to be calling g_module_symbol on them either.
*/
GModule *module = g_module_open (NULL, 0);
if (module == NULL)
g_warning ("gtypelib.c: Failed to g_module_open (NULL): %s", g_module_error ());
else
typelib->modules = g_list_prepend (typelib->modules, module);
}
}
static inline void
_g_typelib_ensure_open (GTypelib *typelib)
{
if (typelib->open_attempted)
return;
typelib->open_attempted = TRUE;
_g_typelib_do_dlopen (typelib);
}
/**
@ -2049,7 +2062,7 @@ g_typelib_new_from_memory (guchar *memory, gsize len)
meta->len = len;
meta->owns_memory = TRUE;
meta->modules = NULL;
_g_typelib_init (meta);
return meta;
}
@ -2072,7 +2085,7 @@ g_typelib_new_from_const_memory (const guchar *memory, gsize len)
meta->len = len;
meta->owns_memory = FALSE;
meta->modules = NULL;
_g_typelib_init (meta);
return meta;
}
@ -2094,7 +2107,7 @@ g_typelib_new_from_mapped_file (GMappedFile *mfile)
meta->owns_memory = FALSE;
meta->data = (guchar *) g_mapped_file_get_contents (mfile);
meta->len = g_mapped_file_get_length (mfile);
_g_typelib_init (meta);
return meta;
}
@ -2140,21 +2153,19 @@ gboolean
g_typelib_symbol (GTypelib *typelib, const char *symbol_name, gpointer *symbol)
{
GList *l;
_g_typelib_ensure_open (typelib);
/*
* We want to be able to add symbols to an app or an auxiliary
* library to fill in gaps in an introspected library. However,
* normally we would only look for symbols in the main library
* (the first items in typelib->modules).
*
* A more elaborate solution is probably possible, but as a
* simple approach for now, if we fail to find a symbol we look
* for it in the global module (the last item in type->modules).
*
* This would not be very efficient if it happened often, since
* we always do the failed lookup above first, but very few
* symbols should be outside of the main libraries in
* typelib->modules so it doesn't matter.
* The reason for having multiple modules dates from gir-repository
* when it was desired to inject code (accessors, etc.) into an
* existing library. In that situation, the first module listed
* will be the custom one, which overrides the main one. A bit
* inefficient, but the problem will go away when gir-repository
* does.
*
* For modules with no shared library, we dlopen'd the current
* process above.
*/
for (l = typelib->modules; l; l = l->next)
{

1
gtypelib.h
View File

@ -1021,6 +1021,7 @@ struct _GTypelib {
gboolean owns_memory;
GMappedFile *mfile;
GList *modules;
gboolean open_attempted;
};
DirEntry *g_typelib_get_dir_entry (GTypelib *typelib,