1 /* GObject - GLib Type, Object, Parameter and Signal Library
2 * Copyright (C) 1998-1999, 2000-2001 Tim Janik and Red Hat, Inc.
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General
15 * Public License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
17 * Boston, MA 02111-1307, USA.
29 #include "gtype-private.h"
31 #include "gvaluecollector.h"
35 * SECTION:enumerations_flags
36 * @short_description: Enumeration and flags types
37 * @title: Enumeration and Flag Types
38 * @see_also:#GParamSpecEnum, #GParamSpecFlags, g_param_spec_enum(),
39 * g_param_spec_flags()
41 * The GLib type system provides fundamental types for enumeration and
42 * flags types. (Flags types are like enumerations, but allow their
43 * values to be combined by bitwise or). A registered enumeration or
44 * flags type associates a name and a nickname with each allowed
45 * value, and the methods g_enum_get_value_by_name(),
46 * g_enum_get_value_by_nick(), g_flags_get_value_by_name() and
47 * g_flags_get_value_by_nick() can look up values by their name or
48 * nickname. When an enumeration or flags type is registered with the
49 * GLib type system, it can be used as value type for object
50 * properties, using g_param_spec_enum() or g_param_spec_flags().
52 * GObject ships with a utility called <link
53 * linkend="glib-mkenums">glib-mkenums</link> that can construct
54 * suitable type registration functions from C enumeration
59 /* --- prototypes --- */
60 static void g_enum_class_init (GEnumClass *class,
62 static void g_flags_class_init (GFlagsClass *class,
64 static void value_flags_enum_init (GValue *value);
65 static void value_flags_enum_copy_value (const GValue *src_value,
67 static gchar* value_flags_enum_collect_value (GValue *value,
68 guint n_collect_values,
69 GTypeCValue *collect_values,
71 static gchar* value_flags_enum_lcopy_value (const GValue *value,
72 guint n_collect_values,
73 GTypeCValue *collect_values,
76 /* --- functions --- */
78 _g_enum_types_init (void)
80 static gboolean initialized = FALSE;
81 static const GTypeValueTable flags_enum_value_table = {
82 value_flags_enum_init, /* value_init */
83 NULL, /* value_free */
84 value_flags_enum_copy_value, /* value_copy */
85 NULL, /* value_peek_pointer */
86 "i", /* collect_format */
87 value_flags_enum_collect_value, /* collect_value */
88 "p", /* lcopy_format */
89 value_flags_enum_lcopy_value, /* lcopy_value */
94 NULL, /* base_destroy */
95 NULL, /* class_init */
96 NULL, /* class_destroy */
97 NULL, /* class_data */
98 0, /* instance_size */
100 NULL, /* instance_init */
101 &flags_enum_value_table, /* value_table */
103 static const GTypeFundamentalInfo finfo = {
104 G_TYPE_FLAG_CLASSED | G_TYPE_FLAG_DERIVABLE,
108 g_return_if_fail (initialized == FALSE);
113 info.class_size = sizeof (GEnumClass);
114 type = g_type_register_fundamental (G_TYPE_ENUM, g_intern_static_string ("GEnum"), &info, &finfo,
115 G_TYPE_FLAG_ABSTRACT | G_TYPE_FLAG_VALUE_ABSTRACT);
116 g_assert (type == G_TYPE_ENUM);
120 info.class_size = sizeof (GFlagsClass);
121 type = g_type_register_fundamental (G_TYPE_FLAGS, g_intern_static_string ("GFlags"), &info, &finfo,
122 G_TYPE_FLAG_ABSTRACT | G_TYPE_FLAG_VALUE_ABSTRACT);
123 g_assert (type == G_TYPE_FLAGS);
127 value_flags_enum_init (GValue *value)
129 value->data[0].v_long = 0;
133 value_flags_enum_copy_value (const GValue *src_value,
136 dest_value->data[0].v_long = src_value->data[0].v_long;
140 value_flags_enum_collect_value (GValue *value,
141 guint n_collect_values,
142 GTypeCValue *collect_values,
145 value->data[0].v_long = collect_values[0].v_int;
151 value_flags_enum_lcopy_value (const GValue *value,
152 guint n_collect_values,
153 GTypeCValue *collect_values,
156 gint *int_p = collect_values[0].v_pointer;
159 return g_strdup_printf ("value location for '%s' passed as NULL", G_VALUE_TYPE_NAME (value));
161 *int_p = value->data[0].v_long;
167 * g_enum_register_static:
168 * @name: A nul-terminated string used as the name of the new type.
169 * @const_static_values: An array of #GEnumValue structs for the possible
170 * enumeration values. The array is terminated by a struct with all
171 * members being 0. GObject keeps a reference to the data, so it cannot
172 * be stack-allocated.
174 * Registers a new static enumeration type with the name @name.
176 * It is normally more convenient to let <link
177 * linkend="glib-mkenums">glib-mkenums</link> generate a
178 * my_enum_get_type() function from a usual C enumeration definition
179 * than to write one yourself using g_enum_register_static().
181 * Returns: The new type identifier.
184 g_enum_register_static (const gchar *name,
185 const GEnumValue *const_static_values)
187 GTypeInfo enum_type_info = {
188 sizeof (GEnumClass), /* class_size */
189 NULL, /* base_init */
190 NULL, /* base_finalize */
191 (GClassInitFunc) g_enum_class_init,
192 NULL, /* class_finalize */
193 NULL, /* class_data */
194 0, /* instance_size */
196 NULL, /* instance_init */
197 NULL, /* value_table */
201 g_return_val_if_fail (name != NULL, 0);
202 g_return_val_if_fail (const_static_values != NULL, 0);
204 enum_type_info.class_data = const_static_values;
206 type = g_type_register_static (G_TYPE_ENUM, name, &enum_type_info, 0);
212 * g_flags_register_static:
213 * @name: A nul-terminated string used as the name of the new type.
214 * @const_static_values: An array of #GFlagsValue structs for the possible
215 * flags values. The array is terminated by a struct with all members being 0.
216 * GObject keeps a reference to the data, so it cannot be stack-allocated.
218 * Registers a new static flags type with the name @name.
220 * It is normally more convenient to let <link
221 * linkend="glib-mkenums">glib-mkenums</link> generate a
222 * my_flags_get_type() function from a usual C enumeration definition
223 * than to write one yourself using g_flags_register_static().
225 * Returns: The new type identifier.
228 g_flags_register_static (const gchar *name,
229 const GFlagsValue *const_static_values)
231 GTypeInfo flags_type_info = {
232 sizeof (GFlagsClass), /* class_size */
233 NULL, /* base_init */
234 NULL, /* base_finalize */
235 (GClassInitFunc) g_flags_class_init,
236 NULL, /* class_finalize */
237 NULL, /* class_data */
238 0, /* instance_size */
240 NULL, /* instance_init */
241 NULL, /* value_table */
245 g_return_val_if_fail (name != NULL, 0);
246 g_return_val_if_fail (const_static_values != NULL, 0);
248 flags_type_info.class_data = const_static_values;
250 type = g_type_register_static (G_TYPE_FLAGS, name, &flags_type_info, 0);
256 * g_enum_complete_type_info:
257 * @g_enum_type: the type identifier of the type being completed
258 * @info: (out callee-allocates): the #GTypeInfo struct to be filled in
259 * @const_values: An array of #GEnumValue structs for the possible
260 * enumeration values. The array is terminated by a struct with all
263 * This function is meant to be called from the <literal>complete_type_info</literal>
264 * function of a #GTypePlugin implementation, as in the following
269 * my_enum_complete_type_info (GTypePlugin *plugin,
272 * GTypeValueTable *value_table)
274 * static const GEnumValue values[] = {
275 * { MY_ENUM_FOO, "MY_ENUM_FOO", "foo" },
276 * { MY_ENUM_BAR, "MY_ENUM_BAR", "bar" },
280 * g_enum_complete_type_info (type, info, values);
285 g_enum_complete_type_info (GType g_enum_type,
287 const GEnumValue *const_values)
289 g_return_if_fail (G_TYPE_IS_ENUM (g_enum_type));
290 g_return_if_fail (info != NULL);
291 g_return_if_fail (const_values != NULL);
293 info->class_size = sizeof (GEnumClass);
294 info->base_init = NULL;
295 info->base_finalize = NULL;
296 info->class_init = (GClassInitFunc) g_enum_class_init;
297 info->class_finalize = NULL;
298 info->class_data = const_values;
302 * g_flags_complete_type_info:
303 * @g_flags_type: the type identifier of the type being completed
304 * @info: (out callee-allocates): the #GTypeInfo struct to be filled in
305 * @const_values: An array of #GFlagsValue structs for the possible
306 * enumeration values. The array is terminated by a struct with all
309 * This function is meant to be called from the complete_type_info()
310 * function of a #GTypePlugin implementation, see the example for
311 * g_enum_complete_type_info() above.
314 g_flags_complete_type_info (GType g_flags_type,
316 const GFlagsValue *const_values)
318 g_return_if_fail (G_TYPE_IS_FLAGS (g_flags_type));
319 g_return_if_fail (info != NULL);
320 g_return_if_fail (const_values != NULL);
322 info->class_size = sizeof (GFlagsClass);
323 info->base_init = NULL;
324 info->base_finalize = NULL;
325 info->class_init = (GClassInitFunc) g_flags_class_init;
326 info->class_finalize = NULL;
327 info->class_data = const_values;
331 g_enum_class_init (GEnumClass *class,
334 g_return_if_fail (G_IS_ENUM_CLASS (class));
339 class->values = class_data;
345 class->minimum = class->values->value;
346 class->maximum = class->values->value;
347 for (values = class->values; values->value_name; values++)
349 class->minimum = MIN (class->minimum, values->value);
350 class->maximum = MAX (class->maximum, values->value);
357 g_flags_class_init (GFlagsClass *class,
360 g_return_if_fail (G_IS_FLAGS_CLASS (class));
364 class->values = class_data;
370 for (values = class->values; values->value_name; values++)
372 class->mask |= values->value;
379 * g_enum_get_value_by_name:
380 * @enum_class: a #GEnumClass
381 * @name: the name to look up
383 * Looks up a #GEnumValue by name.
385 * Returns: (transfer none): the #GEnumValue with name @name,
386 * or %NULL if the enumeration doesn't have a member
390 g_enum_get_value_by_name (GEnumClass *enum_class,
393 g_return_val_if_fail (G_IS_ENUM_CLASS (enum_class), NULL);
394 g_return_val_if_fail (name != NULL, NULL);
396 if (enum_class->n_values)
398 GEnumValue *enum_value;
400 for (enum_value = enum_class->values; enum_value->value_name; enum_value++)
401 if (strcmp (name, enum_value->value_name) == 0)
409 * g_flags_get_value_by_name:
410 * @flags_class: a #GFlagsClass
411 * @name: the name to look up
413 * Looks up a #GFlagsValue by name.
415 * Returns: (transfer none): the #GFlagsValue with name @name,
416 * or %NULL if there is no flag with that name
419 g_flags_get_value_by_name (GFlagsClass *flags_class,
422 g_return_val_if_fail (G_IS_FLAGS_CLASS (flags_class), NULL);
423 g_return_val_if_fail (name != NULL, NULL);
425 if (flags_class->n_values)
427 GFlagsValue *flags_value;
429 for (flags_value = flags_class->values; flags_value->value_name; flags_value++)
430 if (strcmp (name, flags_value->value_name) == 0)
438 * g_enum_get_value_by_nick:
439 * @enum_class: a #GEnumClass
440 * @nick: the nickname to look up
442 * Looks up a #GEnumValue by nickname.
444 * Returns: (transfer none): the #GEnumValue with nickname @nick,
445 * or %NULL if the enumeration doesn't have a member
449 g_enum_get_value_by_nick (GEnumClass *enum_class,
452 g_return_val_if_fail (G_IS_ENUM_CLASS (enum_class), NULL);
453 g_return_val_if_fail (nick != NULL, NULL);
455 if (enum_class->n_values)
457 GEnumValue *enum_value;
459 for (enum_value = enum_class->values; enum_value->value_name; enum_value++)
460 if (enum_value->value_nick && strcmp (nick, enum_value->value_nick) == 0)
468 * g_flags_get_value_by_nick:
469 * @flags_class: a #GFlagsClass
470 * @nick: the nickname to look up
472 * Looks up a #GFlagsValue by nickname.
474 * Returns: (transfer none): the #GFlagsValue with nickname @nick,
475 * or %NULL if there is no flag with that nickname
478 g_flags_get_value_by_nick (GFlagsClass *flags_class,
481 g_return_val_if_fail (G_IS_FLAGS_CLASS (flags_class), NULL);
482 g_return_val_if_fail (nick != NULL, NULL);
484 if (flags_class->n_values)
486 GFlagsValue *flags_value;
488 for (flags_value = flags_class->values; flags_value->value_nick; flags_value++)
489 if (flags_value->value_nick && strcmp (nick, flags_value->value_nick) == 0)
498 * @enum_class: a #GEnumClass
499 * @value: the value to look up
501 * Returns the #GEnumValue for a value.
503 * Returns: (transfer none): the #GEnumValue for @value, or %NULL
504 * if @value is not a member of the enumeration
507 g_enum_get_value (GEnumClass *enum_class,
510 g_return_val_if_fail (G_IS_ENUM_CLASS (enum_class), NULL);
512 if (enum_class->n_values)
514 GEnumValue *enum_value;
516 for (enum_value = enum_class->values; enum_value->value_name; enum_value++)
517 if (enum_value->value == value)
525 * g_flags_get_first_value:
526 * @flags_class: a #GFlagsClass
529 * Returns the first #GFlagsValue which is set in @value.
531 * Returns: (transfer none): the first #GFlagsValue which is set in
532 * @value, or %NULL if none is set
535 g_flags_get_first_value (GFlagsClass *flags_class,
538 g_return_val_if_fail (G_IS_FLAGS_CLASS (flags_class), NULL);
540 if (flags_class->n_values)
542 GFlagsValue *flags_value;
546 for (flags_value = flags_class->values; flags_value->value_name; flags_value++)
547 if (flags_value->value == 0)
552 for (flags_value = flags_class->values; flags_value->value_name; flags_value++)
553 if (flags_value->value != 0 && (flags_value->value & value) == flags_value->value)
563 * @value: a valid #GValue whose type is derived from %G_TYPE_ENUM
564 * @v_enum: enum value to be set
566 * Set the contents of a %G_TYPE_ENUM #GValue to @v_enum.
569 g_value_set_enum (GValue *value,
572 g_return_if_fail (G_VALUE_HOLDS_ENUM (value));
574 value->data[0].v_long = v_enum;
579 * @value: a valid #GValue whose type is derived from %G_TYPE_ENUM
581 * Get the contents of a %G_TYPE_ENUM #GValue.
583 * Returns: enum contents of @value
586 g_value_get_enum (const GValue *value)
588 g_return_val_if_fail (G_VALUE_HOLDS_ENUM (value), 0);
590 return value->data[0].v_long;
595 * @value: a valid #GValue whose type is derived from %G_TYPE_FLAGS
596 * @v_flags: flags value to be set
598 * Set the contents of a %G_TYPE_FLAGS #GValue to @v_flags.
601 g_value_set_flags (GValue *value,
604 g_return_if_fail (G_VALUE_HOLDS_FLAGS (value));
606 value->data[0].v_ulong = v_flags;
611 * @value: a valid #GValue whose type is derived from %G_TYPE_FLAGS
613 * Get the contents of a %G_TYPE_FLAGS #GValue.
615 * Returns: flags contents of @value
618 g_value_get_flags (const GValue *value)
620 g_return_val_if_fail (G_VALUE_HOLDS_FLAGS (value), 0);
622 return value->data[0].v_ulong;