vasilito
facf0c92e0
Red Bear OS is a full fork. All sources must be available from git clone with zero network access. Removed gitignore rules that excluded fetched source trees under recipes/*/source/, local/recipes/kde/*/source/, local/recipes/qt/*/source/, and vendor source trees. Build artifacts (target/, build/, source.tar, *.o, *.so) remain excluded. 127291 files added — kernel, relibc, base, bootloader, pkgar, all KDE/Qt frameworks, mesa, wayland, DRM drivers, and every other recipe source.
2.9 KiB
Title: Dynamic Loading of Modules
Dynamic Loading of Modules
These functions provide a portable way to dynamically load object files
(commonly known as 'plug-ins'). The current implementation supports all
systems that provide an implementation of dlopen() (e.g. Linux/Sun), as
well as Windows platforms via DLLs.
Do not call these functions from within global constructors (for example, those
using GCC’s __attribute__((constructor)) attribute) as this may lead to deadlock.
A program which wants to use these functions must be linked to the libraries output by the command:
pkg-config --libs gmodule-2.0
To use them you must first determine whether dynamic loading is supported on
the platform by calling [func@GModule.Module.supported]. If it is, you can
open a module with [func@GModule.Module.open], find the module's symbols
(e.g. function names) with [method@GModule.Module.symbol], and later close
the module with [method@GModule.Module.close].
[method@GModule.Module.name] will return the file name of a currently
opened module.
If any of the above functions fail, the error status can be found with
[func@GModule.Module.error].
The GModule implementation features reference counting for opened modules,
and supports hook functions within a module which are called when the module
is loaded and unloaded (see [callback@GModule.ModuleCheckInit] and
[callback@GModule.ModuleUnload]).
If your module introduces static data to common subsystems in the running program, e.g. through calling API like:
static GQuark my_module_quark =
g_quark_from_static_string ("my-module-stuff");
it must ensure that it is never unloaded, by calling
[method@GModule.Module.make_resident].
Calling a function defined in a GModule
// the function signature for 'say_hello'
typedef void (* SayHelloFunc) (const char *message);
gboolean
just_say_hello (const char *filename, GError **error)
{
SayHelloFunc say_hello;
GModule *module;
module = g_module_open (filename, G_MODULE_BIND_LAZY);
if (module == NULL)
{
g_set_error (error, FOO_ERROR, FOO_ERROR_BLAH,
"%s", g_module_error ());
return FALSE;
}
if (!g_module_symbol (module, "say_hello", (gpointer *)&say_hello))
{
g_set_error (error, SAY_ERROR, SAY_ERROR_OPEN,
"%s: %s", filename, g_module_error ());
if (!g_module_close (module))
g_warning ("%s: %s", filename, g_module_error ());
return FALSE;
}
if (say_hello == NULL)
{
g_set_error (error, SAY_ERROR, SAY_ERROR_OPEN,
"symbol say_hello is NULL");
if (!g_module_close (module))
g_warning ("%s: %s", filename, g_module_error ());
return FALSE;
}
// call our function in the module
say_hello ("Hello world!");
if (!g_module_close (module))
g_warning ("%s: %s", filename, g_module_error ());
return TRUE;
}