* Defined to 1 if gcc-style visibility handling is supported.
*/
+/* g_auto(), g_autoptr() and helpers {{{1 */
+
+/**
+ * g_auto:
+ * @typename: a supported variable type
+ *
+ * Helper to declare a variable with automatic cleanup.
+ *
+ * The variable is cleaned up in a way appropriate to its type when the
+ * variable goes out of scope. The type must support this.
+ *
+ * This feature is only supported on GCC and clang. This macro is not
+ * defined on other compilers and should not be used in programs that
+ * are intended to be portable to those compilers.
+ *
+ * This is meant to be used with stack-allocated structures and
+ * non-pointer types. For the (more commonly used) pointer version, see
+ * g_autoptr().
+ *
+ * This macro can be used to avoid having to do explicit cleanups of
+ * local variables when exiting functions. It often vastly simplifies
+ * handling of error conditions, removing the need for various tricks
+ * such as 'goto out' or repeating of cleanup code. It is also helpful
+ * for non-error cases.
+ *
+ * Consider the following example:
+ *
+ * |[
+ * GVariant *
+ * my_func(void)
+ * {
+ * g_auto(GQueue) queue = G_QUEUE_INIT;
+ * g_auto(GVariantBuilder) builder;
+ *
+ * g_variant_builder_init (&builder, G_VARIANT_TYPE_VARDICT);
+ *
+ * ...
+ *
+ * if (error_condition)
+ * return NULL;
+ *
+ * ...
+ *
+ * return g_variant_builder_end (&builder);
+ * }
+ * ]|
+ *
+ * You must initialise the variable in some way -- either by use of an
+ * initialiser or by ensuring that an _init function will be called on
+ * it unconditionally before it goes out of scope.
+ *
+ * Since: 2.44
+ */
+
+/**
+ * g_autoptr:
+ * @typename: a supported variable type
+ *
+ * Helper to declare a pointer variable with automatic cleanup.
+ *
+ * The variable is cleaned up in a way appropriate to its type when the
+ * variable goes out of scope. The type must support this.
+ *
+ * This feature is only supported on GCC and clang. This macro is not
+ * defined on other compilers and should not be used in programs that
+ * are intended to be portable to those compilers.
+ *
+ * This is meant to be used to declare pointers to types with cleanup
+ * functions. The type of the variable is a pointer to @typename. You
+ * must not add your own '*'.
+ *
+ * This macro can be used to avoid having to do explicit cleanups of
+ * local variables when exiting functions. It often vastly simplifies
+ * handling of error conditions, removing the need for various tricks
+ * such as 'goto out' or repeating of cleanup code. It is also helpful
+ * for non-error cases.
+ *
+ * Consider the following example:
+ *
+ * |[
+ * gboolean
+ * check_exists(GVariant *dict)
+ * {
+ * g_autoptr(GVariant) dirname;
+ * g_autoptr(GVariant) basename = NULL;
+ * g_autoptr(gchar) path = NULL;
+ *
+ * dirname = g_variant_lookup_value (dict, "dirname", G_VARIANT_TYPE_STRING);
+ *
+ * if (dirname == NULL)
+ * return FALSE;
+ *
+ * basename = g_variant_lookup_value (dict, "basename", G_VARIANT_TYPE_STRING);
+ *
+ * if (basename == NULL)
+ * return FALSE;
+ *
+ * path = g_build_filename (g_variant_get_string (dirname, NULL),
+ * g_variant_get_string (basename, NULL),
+ * NULL);
+ *
+ * return g_access (path, R_OK) == 0;
+ * }
+ * ]|
+ *
+ * You must initialise the variable in some way -- either by use of an
+ * initialiser or by ensuring that it is assigned to unconditionally
+ * before it goes out of scope.
+ *
+ * Since: 2.44
+ */
+
+/**
+ * G_DEFINE_AUTOPTR_CLEANUP_FUNC:
+ * @TypeName: a type name to define a g_autoptr() cleanup function for
+ * @func: the cleanup function
+ *
+ * Defines the appropriate cleanup function for a pointer type.
+ *
+ * The function will not be called if the variable to be cleaned up
+ * contains %NULL.
+ *
+ * This will typically be the _free() or _unref() function for the given
+ * type.
+ *
+ * With this definition, it will be possible to use g_autoptr() with
+ * @TypeName.
+ *
+ * |[
+ * G_DEFINE_AUTOPTR_CLEANUP_FUNC(GObject, g_object_unref)
+ * ]|
+ *
+ * This macro should be used unconditionally; it is a no-op on compilers
+ * where cleanup is not supported.
+ *
+ * Since: 2.44
+ */
+
+/**
+ * G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC:
+ * @TypeName: a type name to define a g_auto() cleanup function for
+ * @func: the clear function
+ *
+ * Defines the appropriate cleanup function for a type.
+ *
+ * This will typically be the _clear() function for the given type.
+ *
+ * With this definition, it will be possible to use g_auto() with
+ * @TypeName.
+ *
+ * |[
+ * G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC(GQueue, g_queue_clear)
+ * ]|
+ *
+ * This macro should be used unconditionally; it is a no-op on compilers
+ * where cleanup is not supported.
+ *
+ * Since: 2.44
+ */
+
+/**
+ * G_DEFINE_AUTO_CLEANUP_FREE_FUNC:
+ * @TypeName: a type name to define a g_auto() cleanup function for
+ * @func: the free function
+ * @none: the "none" value for the type
+ *
+ * Defines the appropriate cleanup function for a type.
+ *
+ * With this definition, it will be possible to use g_auto() with
+ * @TypeName.
+ *
+ * This function will be rarely used. It is used with pointer-based
+ * typedefs and non-pointer types where the value of the variable
+ * represents a resource that must be freed. Two examples are #GStrv
+ * and file descriptors.
+ *
+ * @none specifies the "none" value for the type in question. It is
+ * probably something like %NULL or -1. If the variable is found to
+ * contain this value then the free function will not be called.
+ *
+ * |[
+ * G_DEFINE_AUTO_CLEANUP_FREE_FUNC(GStrv, g_strfreev, NULL)
+ * ]|
+ *
+ * This macro should be used unconditionally; it is a no-op on compilers
+ * where cleanup is not supported.
+ *
+ * Since: 2.44
+ */
+
/* Windows Compatibility Functions {{{1 */
/**
#define GLIB_UNAVAILABLE(maj,min) G_UNAVAILABLE(maj,min) _GLIB_EXTERN
#endif
+#ifdef __GNUC__
+
+/* these macros are private */
+#define _GLIB_AUTOPTR_FUNC_NAME(TypeName) glib_autoptr_cleanup_##TypeName
+#define _GLIB_AUTOPTR_TYPENAME(TypeName) TypeName##_autoptr
+#define _GLIB_AUTO_FUNC_NAME(TypeName) glib_auto_cleanup_##TypeName
+#define _GLIB_CLEANUP(func) __attribute__((cleanup(func)))
+
+/* these macros are API */
+#define G_DEFINE_AUTOPTR_CLEANUP_FUNC(TypeName, func) \
+ typedef TypeName *_GLIB_AUTOPTR_TYPENAME(TypeName); \
+ G_GNUC_BEGIN_IGNORE_DEPRECATIONS \
+ static inline void _GLIB_AUTOPTR_FUNC_NAME(TypeName) (TypeName **_ptr) { if (*_ptr) (func) (*_ptr); } \
+ G_GNUC_END_IGNORE_DEPRECATIONS
+#define G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC(TypeName, func) \
+ G_GNUC_BEGIN_IGNORE_DEPRECATIONS \
+ static inline void _GLIB_AUTO_FUNC_NAME(TypeName) (TypeName *_ptr) { (func) (_ptr); } \
+ G_GNUC_END_IGNORE_DEPRECATIONS
+#define G_DEFINE_AUTO_CLEANUP_FREE_FUNC(TypeName, func, none) \
+ G_GNUC_BEGIN_IGNORE_DEPRECATIONS \
+ static inline void _GLIB_AUTO_FUNC_NAME(TypeName) (TypeName *_ptr) { if (*_ptr != none) (func) (*_ptr); } \
+ G_GNUC_END_IGNORE_DEPRECATIONS
+#define g_autoptr(TypeName) _GLIB_CLEANUP(_GLIB_AUTOPTR_FUNC_NAME(TypeName)) _GLIB_AUTOPTR_TYPENAME(TypeName)
+#define g_auto(TypeName) _GLIB_CLEANUP(_GLIB_AUTO_FUNC_NAME(TypeName)) TypeName
+
+#else /* not GNU C */
+
+#define G_DEFINE_AUTOPTR_CLEANUP_FUNC(TypeName, func)
+#define G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC(TypeName, func)
+#define G_DEFINE_AUTO_CLEANUP_FREE_FUNC(TypeName, func)
+
+/* no declaration of g_auto() or g_autoptr() here */
+#endif
+
#endif /* __G_MACROS_H__ */