* Author: Alexander Larsson <alexl@redhat.com>
*/
-#include <config.h>
+#include "config.h"
+
+#include <string.h>
#include "giomodule.h"
#include "giomodule-priv.h"
+#include "gmemorysettingsbackend.h"
#include "glocalfilemonitor.h"
#include "glocaldirectorymonitor.h"
#include "gnativevolumemonitor.h"
#include "gvfs.h"
-
+#ifdef G_OS_UNIX
+#include "gdesktopappinfo.h"
+#endif
#include "gioalias.h"
+#include <glib/gstdio.h>
/**
* SECTION:giomodule
* @short_description: Loadable GIO Modules
- * @include: gio.h
+ * @include: gio/gio.h
*
* Provides an interface and default functions for loading and unloading
- * modules. This is used internally to make gio extensible, but can also
- * be used by other to implement module loading.
+ * modules. This is used internally to make GIO extensible, but can also
+ * be used by others to implement module loading.
*
**/
+/**
+ * SECTION:extensionpoints
+ * @short_description: Extension Points
+ * @include: gio.h
+ * @see_also: <link linkend="extending-gio">Extending GIO</link>
+ *
+ * #GIOExtensionPoint provides a mechanism for modules to extend the
+ * functionality of the library or application that loaded it in an
+ * organized fashion.
+ *
+ * An extension point is identified by a name, and it may optionally
+ * require that any implementation must by of a certain type (or derived
+ * thereof). Use g_io_extension_point_register() to register an
+ * extension point, and g_io_extension_point_set_required_type() to
+ * set a required type.
+ *
+ * A module can implement an extension point by specifying the #GType
+ * that implements the functionality. Additionally, each implementation
+ * of an extension point has a name, and a priority. Use
+ * g_io_extension_point_implement() to implement an extension point.
+ *
+ * |[
+ * GIOExtensionPoint *ep;
+ *
+ * /* Register an extension point */
+ * ep = g_io_extension_point_register ("my-extension-point");
+ * g_io_extension_point_set_required_type (ep, MY_TYPE_EXAMPLE);
+ * ]|
+ *
+ * |[
+ * /* Implement an extension point */
+ * G_DEFINE_TYPE (MyExampleImpl, my_example_impl, MY_TYPE_EXAMPLE);
+ * g_io_extension_point_implement ("my-extension-point",
+ * my_example_impl_get_type (),
+ * "my-example",
+ * 10);
+ * ]|
+ *
+ * It is up to the code that registered the extension point how
+ * it uses the implementations that have been associated with it.
+ * Depending on the use case, it may use all implementations, or
+ * only the one with the highest priority, or pick a specific
+ * one by name.
+ *
+ * To avoid opening all modules just to find out what extension
+ * points they implement, GIO makes use of a caching mechanism,
+ * see <link linkend="gio-querymodules">gio-querymodules</link>.
+ * You are expected to run this command after installing a
+ * GIO module.
+ */
struct _GIOModule {
GTypeModule parent_instance;
-
+
gchar *filename;
GModule *library;
-
+ gboolean initialized; /* The module was loaded at least once */
+
void (* load) (GIOModule *module);
void (* unload) (GIOModule *module);
};
static gboolean g_io_module_load_module (GTypeModule *gmodule);
static void g_io_module_unload_module (GTypeModule *gmodule);
+struct _GIOExtension {
+ char *name;
+ GType type;
+ gint priority;
+};
+
+struct _GIOExtensionPoint {
+ GType required_type;
+ char *name;
+ GList *extensions;
+ GList *lazy_load_modules;
+};
+
+static GHashTable *extension_points = NULL;
+G_LOCK_DEFINE_STATIC(extension_points);
+
G_DEFINE_TYPE (GIOModule, g_io_module, G_TYPE_TYPE_MODULE);
static void
/* Initialize the loaded module */
module->load (module);
+ module->initialized = TRUE;
return TRUE;
}
}
/**
+ * g_io_modules_scan_all_in_directory:
+ * @dirname: pathname for a directory containing modules to scan.
+ *
+ * Scans all the modules in the specified directory, ensuring that
+ * any extension point implemented by a module is registered.
+ *
+ * This may not actually load and initialize all the types in each
+ * module, some modules may be lazily loaded and initialized when
+ * an extension point it implementes is used with e.g.
+ * g_io_extension_point_get_extensions() or
+ * g_io_extension_point_get_extension_by_name().
+ *
+ * If you need to guarantee that all types are loaded in all the modules,
+ * use g_io_modules_scan_all_in_directory().
+ *
+ * Since: 2.24
+ **/
+void
+g_io_modules_scan_all_in_directory (const char *dirname)
+{
+ const gchar *name;
+ char *filename;
+ GDir *dir;
+ GStatBuf statbuf;
+ char *data;
+ time_t cache_mtime;
+ GHashTable *cache;
+
+ if (!g_module_supported ())
+ return;
+
+ dir = g_dir_open (dirname, 0, NULL);
+ if (!dir)
+ return;
+
+ filename = g_build_filename (dirname, "giomodule.cache", NULL);
+
+ cache = g_hash_table_new_full (g_str_hash, g_str_equal,
+ g_free, (GDestroyNotify)g_strfreev);
+
+ cache_mtime = 0;
+ if (g_stat (filename, &statbuf) == 0 &&
+ g_file_get_contents (filename, &data, NULL, NULL))
+ {
+ char **lines;
+ int i;
+
+ /* Cache mtime is the time the cache file was created, any file
+ * that has a ctime before this was created then and not modified
+ * since then (userspace can't change ctime). Its possible to change
+ * the ctime forward without changing the file content, by e.g.
+ * chmoding the file, but this is uncommon and will only cause us
+ * to not use the cache so will not cause bugs.
+ */
+ cache_mtime = statbuf.st_mtime;
+
+ lines = g_strsplit (data, "\n", -1);
+ g_free (data);
+
+ for (i = 0; lines[i] != NULL; i++)
+ {
+ char *line = lines[i];
+ char *file;
+ char *colon;
+ char **extension_points;
+
+ if (line[0] == '#')
+ continue;
+
+ colon = strchr (line, ':');
+ if (colon == NULL || line == colon)
+ continue; /* Invalid line, ignore */
+
+ *colon = 0; /* terminate filename */
+ file = g_strdup (line);
+ colon++; /* after colon */
+
+ while (g_ascii_isspace (*colon))
+ colon++;
+
+ extension_points = g_strsplit (colon, ",", -1);
+ g_hash_table_insert (cache, file, extension_points);
+ }
+ g_strfreev (lines);
+ }
+
+ while ((name = g_dir_read_name (dir)))
+ {
+ if (is_valid_module_name (name))
+ {
+ GIOExtensionPoint *extension_point;
+ GIOModule *module;
+ gchar *path;
+ char **extension_points;
+ int i;
+
+ path = g_build_filename (dirname, name, NULL);
+ module = g_io_module_new (path);
+
+ extension_points = g_hash_table_lookup (cache, name);
+ if (extension_points != NULL &&
+ g_stat (path, &statbuf) == 0 &&
+ statbuf.st_ctime <= cache_mtime)
+ {
+ /* Lazy load/init the library when first required */
+ for (i = 0; extension_points[i] != NULL; i++)
+ {
+ extension_point =
+ g_io_extension_point_register (extension_points[i]);
+ extension_point->lazy_load_modules =
+ g_list_prepend (extension_point->lazy_load_modules,
+ module);
+ }
+ }
+ else
+ {
+ /* Try to load and init types */
+ if (g_type_module_use (G_TYPE_MODULE (module)))
+ g_type_module_unuse (G_TYPE_MODULE (module)); /* Unload */
+ else
+ { /* Failure to load */
+ g_printerr ("Failed to load module: %s\n", path);
+ g_object_unref (module);
+ g_free (path);
+ continue;
+ }
+ }
+
+ g_free (path);
+ }
+ }
+
+ g_dir_close (dir);
+
+ g_hash_table_destroy (cache);
+
+ g_free (filename);
+}
+
+
+/**
* g_io_modules_load_all_in_directory:
* @dirname: pathname for a directory containing modules to load.
- *
- * Loads all the modules in the the specified directory.
- *
+ *
+ * Loads all the modules in the specified directory.
+ *
+ * If don't require all modules to be initialized (and thus registering
+ * all gtypes) then you can use g_io_modules_scan_all_in_directory()
+ * which allows delayed/lazy loading of modules.
+ *
* Returns: a list of #GIOModules loaded from the directory,
* All the modules are loaded into memory, if you want to
* unload them (enabling on-demand loading) you must call
return modules;
}
+G_LOCK_DEFINE_STATIC (registered_extensions);
G_LOCK_DEFINE_STATIC (loaded_dirs);
+extern GType _g_fen_directory_monitor_get_type (void);
+extern GType _g_fen_file_monitor_get_type (void);
extern GType _g_inotify_directory_monitor_get_type (void);
extern GType _g_inotify_file_monitor_get_type (void);
extern GType _g_unix_volume_monitor_get_type (void);
extern GType _g_local_vfs_get_type (void);
+extern GType _g_win32_volume_monitor_get_type (void);
+extern GType g_win32_directory_monitor_get_type (void);
+extern GType _g_winhttp_vfs_get_type (void);
+
+#ifdef G_PLATFORM_WIN32
+
+#include <windows.h>
+
+static HMODULE gio_dll = NULL;
+
+#ifdef DLL_EXPORT
+
+BOOL WINAPI
+DllMain (HINSTANCE hinstDLL,
+ DWORD fdwReason,
+ LPVOID lpvReserved)
+{
+ if (fdwReason == DLL_PROCESS_ATTACH)
+ gio_dll = hinstDLL;
+
+ return TRUE;
+}
+
+#endif
+
+#undef GIO_MODULE_DIR
+
+/* GIO_MODULE_DIR is used only in code called just once,
+ * so no problem leaking this
+ */
+#define GIO_MODULE_DIR \
+ g_build_filename (g_win32_get_package_installation_directory_of_module (gio_dll), \
+ "lib/gio/modules", \
+ NULL)
+
+#endif
+
+void
+_g_io_modules_ensure_extension_points_registered (void)
+{
+ static gboolean registered_extensions = FALSE;
+ GIOExtensionPoint *ep;
+
+ G_LOCK (registered_extensions);
+
+ if (!registered_extensions)
+ {
+ registered_extensions = TRUE;
+
+#ifdef G_OS_UNIX
+ ep = g_io_extension_point_register (G_DESKTOP_APP_INFO_LOOKUP_EXTENSION_POINT_NAME);
+ g_io_extension_point_set_required_type (ep, G_TYPE_DESKTOP_APP_INFO_LOOKUP);
+#endif
+
+ ep = g_io_extension_point_register (G_LOCAL_DIRECTORY_MONITOR_EXTENSION_POINT_NAME);
+ g_io_extension_point_set_required_type (ep, G_TYPE_LOCAL_DIRECTORY_MONITOR);
+
+ ep = g_io_extension_point_register (G_LOCAL_FILE_MONITOR_EXTENSION_POINT_NAME);
+ g_io_extension_point_set_required_type (ep, G_TYPE_LOCAL_FILE_MONITOR);
+
+ ep = g_io_extension_point_register (G_VOLUME_MONITOR_EXTENSION_POINT_NAME);
+ g_io_extension_point_set_required_type (ep, G_TYPE_VOLUME_MONITOR);
+
+ ep = g_io_extension_point_register (G_NATIVE_VOLUME_MONITOR_EXTENSION_POINT_NAME);
+ g_io_extension_point_set_required_type (ep, G_TYPE_NATIVE_VOLUME_MONITOR);
+
+ ep = g_io_extension_point_register (G_VFS_EXTENSION_POINT_NAME);
+ g_io_extension_point_set_required_type (ep, G_TYPE_VFS);
+
+ ep = g_io_extension_point_register ("gsettings-backend");
+ g_io_extension_point_set_required_type (ep, G_TYPE_OBJECT);
+ }
+
+ G_UNLOCK (registered_extensions);
+ }
+
void
_g_io_modules_ensure_loaded (void)
{
- GList *modules, *l;
static gboolean loaded_dirs = FALSE;
- int i;
- GType *types;
- guint n_types;
- GQuark private_q, name_q;
+ const char *module_path;
+ _g_io_modules_ensure_extension_points_registered ();
+
G_LOCK (loaded_dirs);
if (!loaded_dirs)
{
loaded_dirs = TRUE;
- modules = g_io_modules_load_all_in_directory (GIO_MODULE_DIR);
- private_q = g_quark_from_static_string ("gio-prio");
- name_q = g_quark_from_static_string ("gio-name");
+ g_io_modules_scan_all_in_directory (GIO_MODULE_DIR);
+
+ module_path = g_getenv ("GIO_EXTRA_MODULES");
+
+ if (module_path)
+ {
+ gchar **paths;
+ int i;
+
+ paths = g_strsplit (module_path, ":", 0);
+
+ for (i = 0; paths[i] != NULL; i++)
+ g_io_modules_scan_all_in_directory (paths[i]);
+
+ g_strfreev (paths);
+ }
/* Initialize types from built-in "modules" */
+ g_memory_settings_backend_get_type ();
#if defined(HAVE_SYS_INOTIFY_H) || defined(HAVE_LINUX_INOTIFY_H)
_g_inotify_directory_monitor_get_type ();
_g_inotify_file_monitor_get_type ();
#endif
+#if defined(HAVE_FEN)
+ _g_fen_directory_monitor_get_type ();
+ _g_fen_file_monitor_get_type ();
+#endif
+#ifdef G_OS_WIN32
+ _g_win32_volume_monitor_get_type ();
+ g_win32_directory_monitor_get_type ();
+#endif
#ifdef G_OS_UNIX
_g_unix_volume_monitor_get_type ();
#endif
+#ifdef G_OS_WIN32
+ _g_winhttp_vfs_get_type ();
+#endif
_g_local_vfs_get_type ();
+ }
- /* Copy over all prios to static gtype data so
- * we can avoid loading the module again
- */
+ G_UNLOCK (loaded_dirs);
+}
- types = g_type_children (G_TYPE_LOCAL_FILE_MONITOR, &n_types);
- for (i = 0; i < n_types; i++)
- {
- GLocalFileMonitorClass *klass = g_type_class_ref (types[i]);
- g_type_set_qdata (types[i], private_q, GINT_TO_POINTER (klass->prio));
- g_type_class_unref (klass);
- }
- g_free (types);
+static void
+g_io_extension_point_free (GIOExtensionPoint *ep)
+{
+ g_free (ep->name);
+ g_free (ep);
+}
- types = g_type_children (G_TYPE_LOCAL_DIRECTORY_MONITOR, &n_types);
- for (i = 0; i < n_types; i++)
- {
- GLocalDirectoryMonitorClass *klass = g_type_class_ref (types[i]);
- g_type_set_qdata (types[i], private_q, GINT_TO_POINTER (klass->prio));
- g_type_class_unref (klass);
- }
- g_free (types);
+/**
+ * g_io_extension_point_register:
+ * @name: The name of the extension point
+ *
+ * Registers an extension point.
+ *
+ * Returns: the new #GIOExtensionPoint. This object is owned by GIO
+ * and should not be freed
+ */
+GIOExtensionPoint *
+g_io_extension_point_register (const char *name)
+{
+ GIOExtensionPoint *ep;
+
+ G_LOCK (extension_points);
+ if (extension_points == NULL)
+ extension_points = g_hash_table_new_full (g_str_hash,
+ g_str_equal,
+ NULL,
+ (GDestroyNotify)g_io_extension_point_free);
+
+ ep = g_hash_table_lookup (extension_points, name);
+ if (ep != NULL)
+ {
+ G_UNLOCK (extension_points);
+ return ep;
+ }
- types = g_type_children (G_TYPE_NATIVE_VOLUME_MONITOR, &n_types);
- for (i = 0; i < n_types; i++)
- {
- GNativeVolumeMonitorClass *klass = g_type_class_ref (types[i]);
- g_type_set_qdata (types[i], private_q, GINT_TO_POINTER (klass->priority));
- g_type_set_qdata (types[i], name_q, g_strdup (klass->name));
- g_type_class_unref (klass);
- }
- g_free (types);
-
- types = g_type_children (G_TYPE_VFS, &n_types);
- for (i = 0; i < n_types; i++)
+ ep = g_new0 (GIOExtensionPoint, 1);
+ ep->name = g_strdup (name);
+
+ g_hash_table_insert (extension_points, ep->name, ep);
+
+ G_UNLOCK (extension_points);
+
+ return ep;
+}
+
+/**
+ * g_io_extension_point_lookup:
+ * @name: the name of the extension point
+ *
+ * Looks up an existing extension point.
+ *
+ * Returns: the #GIOExtensionPoint, or %NULL if there is no
+ * registered extension point with the given name
+ */
+GIOExtensionPoint *
+g_io_extension_point_lookup (const char *name)
+{
+ GIOExtensionPoint *ep;
+
+ G_LOCK (extension_points);
+ ep = NULL;
+ if (extension_points != NULL)
+ ep = g_hash_table_lookup (extension_points, name);
+
+ G_UNLOCK (extension_points);
+
+ return ep;
+
+}
+
+/**
+ * g_io_extension_point_set_required_type:
+ * @extension_point: a #GIOExtensionPoint
+ * @type: the #GType to require
+ *
+ * Sets the required type for @extension_point to @type.
+ * All implementations must henceforth have this type.
+ */
+void
+g_io_extension_point_set_required_type (GIOExtensionPoint *extension_point,
+ GType type)
+{
+ extension_point->required_type = type;
+}
+
+/**
+ * g_io_extension_point_get_required_type:
+ * @extension_point: a #GIOExtensionPoint
+ *
+ * Gets the required type for @extension_point.
+ *
+ * Returns: the #GType that all implementations must have,
+ * or #G_TYPE_INVALID if the extension point has no required type
+ */
+GType
+g_io_extension_point_get_required_type (GIOExtensionPoint *extension_point)
+{
+ return extension_point->required_type;
+}
+
+void
+lazy_load_modules (GIOExtensionPoint *extension_point)
+{
+ GIOModule *module;
+ GList *l;
+
+ for (l = extension_point->lazy_load_modules; l != NULL; l = l->next)
+ {
+ module = l->data;
+
+ if (!module->initialized)
{
- GVfsClass *klass = g_type_class_ref (types[i]);
- g_type_set_qdata (types[i], private_q, GINT_TO_POINTER (klass->priority));
- g_type_set_qdata (types[i], name_q, g_strdup (klass->name));
- g_type_class_unref (klass);
+ if (g_type_module_use (G_TYPE_MODULE (module)))
+ g_type_module_unuse (G_TYPE_MODULE (module)); /* Unload */
+ else
+ g_printerr ("Failed to load module: %s\n",
+ module->filename);
}
- g_free (types);
-
- for (l = modules; l != NULL; l = l->next)
- g_type_module_unuse (G_TYPE_MODULE (l->data));
-
- g_list_free (modules);
}
+}
- G_UNLOCK (loaded_dirs);
+/**
+ * g_io_extension_point_get_extensions:
+ * @extension_point: a #GIOExtensionPoint
+ *
+ * Gets a list of all extensions that implement this extension point.
+ * The list is sorted by priority, beginning with the highest priority.
+ *
+ * Returns: a #GList of #GIOExtension<!-- -->s. The list is owned by
+ * GIO and should not be modified
+ */
+GList *
+g_io_extension_point_get_extensions (GIOExtensionPoint *extension_point)
+{
+ lazy_load_modules (extension_point);
+ return extension_point->extensions;
+}
+
+/**
+ * g_io_extension_point_get_extension_by_name:
+ * @extension_point: a #GIOExtensionPoint
+ * @name: the name of the extension to get
+ *
+ * Finds a #GIOExtension for an extension point by name.
+ *
+ * Returns: the #GIOExtension for @extension_point that has the
+ * given name, or %NULL if there is no extension with that name
+ */
+GIOExtension *
+g_io_extension_point_get_extension_by_name (GIOExtensionPoint *extension_point,
+ const char *name)
+{
+ GList *l;
+
+ lazy_load_modules (extension_point);
+ for (l = extension_point->extensions; l != NULL; l = l->next)
+ {
+ GIOExtension *e = l->data;
+
+ if (e->name != NULL &&
+ strcmp (e->name, name) == 0)
+ return e;
+ }
+
+ return NULL;
+}
+
+static gint
+extension_prio_compare (gconstpointer a,
+ gconstpointer b)
+{
+ const GIOExtension *extension_a = a, *extension_b = b;
+
+ return extension_b->priority - extension_a->priority;
+}
+
+/**
+ * g_io_extension_point_implement:
+ * @extension_point_name: the name of the extension point
+ * @type: the #GType to register as extension
+ * @extension_name: the name for the extension
+ * @priority: the priority for the extension
+ *
+ * Registers @type as extension for the extension point with name
+ * @extension_point_name.
+ *
+ * If @type has already been registered as an extension for this
+ * extension point, the existing #GIOExtension object is returned.
+ *
+ * Returns: a #GIOExtension object for #GType
+ */
+GIOExtension *
+g_io_extension_point_implement (const char *extension_point_name,
+ GType type,
+ const char *extension_name,
+ gint priority)
+{
+ GIOExtensionPoint *extension_point;
+ GIOExtension *extension;
+ GList *l;
+
+ g_return_val_if_fail (extension_point_name != NULL, NULL);
+
+ extension_point = g_io_extension_point_lookup (extension_point_name);
+ if (extension_point == NULL)
+ {
+ g_warning ("Tried to implement non-registered extension point %s", extension_point_name);
+ return NULL;
+ }
+
+ if (extension_point->required_type != 0 &&
+ !g_type_is_a (type, extension_point->required_type))
+ {
+ g_warning ("Tried to register an extension of the type %s to extension point %s. "
+ "Expected type is %s.",
+ g_type_name (type),
+ extension_point_name,
+ g_type_name (extension_point->required_type));
+ return NULL;
+ }
+
+ /* It's safe to register the same type multiple times */
+ for (l = extension_point->extensions; l != NULL; l = l->next)
+ {
+ extension = l->data;
+ if (extension->type == type)
+ return extension;
+ }
+
+ extension = g_slice_new0 (GIOExtension);
+ extension->type = type;
+ extension->name = g_strdup (extension_name);
+ extension->priority = priority;
+
+ extension_point->extensions = g_list_insert_sorted (extension_point->extensions,
+ extension, extension_prio_compare);
+
+ return extension;
+}
+
+/**
+ * g_io_extension_ref_class:
+ * @extension: a #GIOExtension
+ *
+ * Gets a reference to the class for the type that is
+ * associated with @extension.
+ *
+ * Returns: the #GTypeClass for the type of @extension
+ */
+GTypeClass *
+g_io_extension_ref_class (GIOExtension *extension)
+{
+ return g_type_class_ref (extension->type);
+}
+
+/**
+ * g_io_extension_get_type:
+ * @extension: a #GIOExtension
+ *
+ * Gets the type associated with @extension.
+ *
+ * Returns: the type of @extension
+ */
+GType
+g_io_extension_get_type (GIOExtension *extension)
+{
+ return extension->type;
+}
+
+/**
+ * g_io_extension_get_name:
+ * @extension: a #GIOExtension
+ *
+ * Gets the name under which @extension was registered.
+ *
+ * Note that the same type may be registered as extension
+ * for multiple extension points, under different names.
+ *
+ * Returns: the name of @extension.
+ */
+const char *
+g_io_extension_get_name (GIOExtension *extension)
+{
+ return extension->name;
+}
+
+/**
+ * g_io_extension_get_priority:
+ * @extension: a #GIOExtension
+ *
+ * Gets the priority with which @extension was registered.
+ *
+ * Returns: the priority of @extension
+ */
+gint
+g_io_extension_get_priority (GIOExtension *extension)
+{
+ return extension->priority;
}
#define __G_IO_MODULE_C__
projects / platform / upstream / glib.git / blobdiff