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, see <http://www.gnu.org/licenses/>.
27 #include "gtype-private.h"
29 #include "gvaluecollector.h"
33 * SECTION:enumerations_flags
34 * @short_description: Enumeration and flags types
35 * @title: Enumeration and Flag Types
36 * @see_also:#GParamSpecEnum, #GParamSpecFlags, g_param_spec_enum(),
37 * g_param_spec_flags()
39 * The GLib type system provides fundamental types for enumeration and
40 * flags types. (Flags types are like enumerations, but allow their
41 * values to be combined by bitwise or). A registered enumeration or
42 * flags type associates a name and a nickname with each allowed
43 * value, and the methods g_enum_get_value_by_name(),
44 * g_enum_get_value_by_nick(), g_flags_get_value_by_name() and
45 * g_flags_get_value_by_nick() can look up values by their name or
46 * nickname. When an enumeration or flags type is registered with the
47 * GLib type system, it can be used as value type for object
48 * properties, using g_param_spec_enum() or g_param_spec_flags().
50 * GObject ships with a utility called <link
51 * linkend="glib-mkenums">glib-mkenums</link> that can construct
52 * suitable type registration functions from C enumeration
57 /* --- prototypes --- */
58 static void g_enum_class_init (GEnumClass *class,
60 static void g_flags_class_init (GFlagsClass *class,
62 static void value_flags_enum_init (GValue *value);
63 static void value_flags_enum_copy_value (const GValue *src_value,
65 static gchar* value_flags_enum_collect_value (GValue *value,
66 guint n_collect_values,
67 GTypeCValue *collect_values,
69 static gchar* value_flags_enum_lcopy_value (const GValue *value,
70 guint n_collect_values,
71 GTypeCValue *collect_values,
74 /* --- functions --- */
76 _g_enum_types_init (void)
78 static gboolean initialized = FALSE;
79 static const GTypeValueTable flags_enum_value_table = {
80 value_flags_enum_init, /* value_init */
81 NULL, /* value_free */
82 value_flags_enum_copy_value, /* value_copy */
83 NULL, /* value_peek_pointer */
84 "i", /* collect_format */
85 value_flags_enum_collect_value, /* collect_value */
86 "p", /* lcopy_format */
87 value_flags_enum_lcopy_value, /* lcopy_value */
92 NULL, /* base_destroy */
93 NULL, /* class_init */
94 NULL, /* class_destroy */
95 NULL, /* class_data */
96 0, /* instance_size */
98 NULL, /* instance_init */
99 &flags_enum_value_table, /* value_table */
101 static const GTypeFundamentalInfo finfo = {
102 G_TYPE_FLAG_CLASSED | G_TYPE_FLAG_DERIVABLE,
106 g_return_if_fail (initialized == FALSE);
111 info.class_size = sizeof (GEnumClass);
112 type = g_type_register_fundamental (G_TYPE_ENUM, g_intern_static_string ("GEnum"), &info, &finfo,
113 G_TYPE_FLAG_ABSTRACT | G_TYPE_FLAG_VALUE_ABSTRACT);
114 g_assert (type == G_TYPE_ENUM);
118 info.class_size = sizeof (GFlagsClass);
119 type = g_type_register_fundamental (G_TYPE_FLAGS, g_intern_static_string ("GFlags"), &info, &finfo,
120 G_TYPE_FLAG_ABSTRACT | G_TYPE_FLAG_VALUE_ABSTRACT);
121 g_assert (type == G_TYPE_FLAGS);
125 value_flags_enum_init (GValue *value)
127 value->data[0].v_long = 0;
131 value_flags_enum_copy_value (const GValue *src_value,
134 dest_value->data[0].v_long = src_value->data[0].v_long;
138 value_flags_enum_collect_value (GValue *value,
139 guint n_collect_values,
140 GTypeCValue *collect_values,
143 value->data[0].v_long = collect_values[0].v_int;
149 value_flags_enum_lcopy_value (const GValue *value,
150 guint n_collect_values,
151 GTypeCValue *collect_values,
154 gint *int_p = collect_values[0].v_pointer;
157 return g_strdup_printf ("value location for '%s' passed as NULL", G_VALUE_TYPE_NAME (value));
159 *int_p = value->data[0].v_long;
165 * g_enum_register_static:
166 * @name: A nul-terminated string used as the name of the new type.
167 * @const_static_values: An array of #GEnumValue structs for the possible
168 * enumeration values. The array is terminated by a struct with all
169 * members being 0. GObject keeps a reference to the data, so it cannot
170 * be stack-allocated.
172 * Registers a new static enumeration type with the name @name.
174 * It is normally more convenient to let <link
175 * linkend="glib-mkenums">glib-mkenums</link> generate a
176 * my_enum_get_type() function from a usual C enumeration definition
177 * than to write one yourself using g_enum_register_static().
179 * Returns: The new type identifier.
182 g_enum_register_static (const gchar *name,
183 const GEnumValue *const_static_values)
185 GTypeInfo enum_type_info = {
186 sizeof (GEnumClass), /* class_size */
187 NULL, /* base_init */
188 NULL, /* base_finalize */
189 (GClassInitFunc) g_enum_class_init,
190 NULL, /* class_finalize */
191 NULL, /* class_data */
192 0, /* instance_size */
194 NULL, /* instance_init */
195 NULL, /* value_table */
199 g_return_val_if_fail (name != NULL, 0);
200 g_return_val_if_fail (const_static_values != NULL, 0);
202 enum_type_info.class_data = const_static_values;
204 type = g_type_register_static (G_TYPE_ENUM, name, &enum_type_info, 0);
210 * g_flags_register_static:
211 * @name: A nul-terminated string used as the name of the new type.
212 * @const_static_values: An array of #GFlagsValue structs for the possible
213 * flags values. The array is terminated by a struct with all members being 0.
214 * GObject keeps a reference to the data, so it cannot be stack-allocated.
216 * Registers a new static flags type with the name @name.
218 * It is normally more convenient to let <link
219 * linkend="glib-mkenums">glib-mkenums</link> generate a
220 * my_flags_get_type() function from a usual C enumeration definition
221 * than to write one yourself using g_flags_register_static().
223 * Returns: The new type identifier.
226 g_flags_register_static (const gchar *name,
227 const GFlagsValue *const_static_values)
229 GTypeInfo flags_type_info = {
230 sizeof (GFlagsClass), /* class_size */
231 NULL, /* base_init */
232 NULL, /* base_finalize */
233 (GClassInitFunc) g_flags_class_init,
234 NULL, /* class_finalize */
235 NULL, /* class_data */
236 0, /* instance_size */
238 NULL, /* instance_init */
239 NULL, /* value_table */
243 g_return_val_if_fail (name != NULL, 0);
244 g_return_val_if_fail (const_static_values != NULL, 0);
246 flags_type_info.class_data = const_static_values;
248 type = g_type_register_static (G_TYPE_FLAGS, name, &flags_type_info, 0);
254 * g_enum_complete_type_info:
255 * @g_enum_type: the type identifier of the type being completed
256 * @info: (out callee-allocates): the #GTypeInfo struct to be filled in
257 * @const_values: An array of #GEnumValue structs for the possible
258 * enumeration values. The array is terminated by a struct with all
261 * This function is meant to be called from the <literal>complete_type_info</literal>
262 * function of a #GTypePlugin implementation, as in the following
267 * my_enum_complete_type_info (GTypePlugin *plugin,
270 * GTypeValueTable *value_table)
272 * static const GEnumValue values[] = {
273 * { MY_ENUM_FOO, "MY_ENUM_FOO", "foo" },
274 * { MY_ENUM_BAR, "MY_ENUM_BAR", "bar" },
278 * g_enum_complete_type_info (type, info, values);
283 g_enum_complete_type_info (GType g_enum_type,
285 const GEnumValue *const_values)
287 g_return_if_fail (G_TYPE_IS_ENUM (g_enum_type));
288 g_return_if_fail (info != NULL);
289 g_return_if_fail (const_values != NULL);
291 info->class_size = sizeof (GEnumClass);
292 info->base_init = NULL;
293 info->base_finalize = NULL;
294 info->class_init = (GClassInitFunc) g_enum_class_init;
295 info->class_finalize = NULL;
296 info->class_data = const_values;
300 * g_flags_complete_type_info:
301 * @g_flags_type: the type identifier of the type being completed
302 * @info: (out callee-allocates): the #GTypeInfo struct to be filled in
303 * @const_values: An array of #GFlagsValue structs for the possible
304 * enumeration values. The array is terminated by a struct with all
307 * This function is meant to be called from the complete_type_info()
308 * function of a #GTypePlugin implementation, see the example for
309 * g_enum_complete_type_info() above.
312 g_flags_complete_type_info (GType g_flags_type,
314 const GFlagsValue *const_values)
316 g_return_if_fail (G_TYPE_IS_FLAGS (g_flags_type));
317 g_return_if_fail (info != NULL);
318 g_return_if_fail (const_values != NULL);
320 info->class_size = sizeof (GFlagsClass);
321 info->base_init = NULL;
322 info->base_finalize = NULL;
323 info->class_init = (GClassInitFunc) g_flags_class_init;
324 info->class_finalize = NULL;
325 info->class_data = const_values;
329 g_enum_class_init (GEnumClass *class,
332 g_return_if_fail (G_IS_ENUM_CLASS (class));
337 class->values = class_data;
343 class->minimum = class->values->value;
344 class->maximum = class->values->value;
345 for (values = class->values; values->value_name; values++)
347 class->minimum = MIN (class->minimum, values->value);
348 class->maximum = MAX (class->maximum, values->value);
355 g_flags_class_init (GFlagsClass *class,
358 g_return_if_fail (G_IS_FLAGS_CLASS (class));
362 class->values = class_data;
368 for (values = class->values; values->value_name; values++)
370 class->mask |= values->value;
377 * g_enum_get_value_by_name:
378 * @enum_class: a #GEnumClass
379 * @name: the name to look up
381 * Looks up a #GEnumValue by name.
383 * Returns: (transfer none): the #GEnumValue with name @name,
384 * or %NULL if the enumeration doesn't have a member
388 g_enum_get_value_by_name (GEnumClass *enum_class,
391 g_return_val_if_fail (G_IS_ENUM_CLASS (enum_class), NULL);
392 g_return_val_if_fail (name != NULL, NULL);
394 if (enum_class->n_values)
396 GEnumValue *enum_value;
398 for (enum_value = enum_class->values; enum_value->value_name; enum_value++)
399 if (strcmp (name, enum_value->value_name) == 0)
407 * g_flags_get_value_by_name:
408 * @flags_class: a #GFlagsClass
409 * @name: the name to look up
411 * Looks up a #GFlagsValue by name.
413 * Returns: (transfer none): the #GFlagsValue with name @name,
414 * or %NULL if there is no flag with that name
417 g_flags_get_value_by_name (GFlagsClass *flags_class,
420 g_return_val_if_fail (G_IS_FLAGS_CLASS (flags_class), NULL);
421 g_return_val_if_fail (name != NULL, NULL);
423 if (flags_class->n_values)
425 GFlagsValue *flags_value;
427 for (flags_value = flags_class->values; flags_value->value_name; flags_value++)
428 if (strcmp (name, flags_value->value_name) == 0)
436 * g_enum_get_value_by_nick:
437 * @enum_class: a #GEnumClass
438 * @nick: the nickname to look up
440 * Looks up a #GEnumValue by nickname.
442 * Returns: (transfer none): the #GEnumValue with nickname @nick,
443 * or %NULL if the enumeration doesn't have a member
447 g_enum_get_value_by_nick (GEnumClass *enum_class,
450 g_return_val_if_fail (G_IS_ENUM_CLASS (enum_class), NULL);
451 g_return_val_if_fail (nick != NULL, NULL);
453 if (enum_class->n_values)
455 GEnumValue *enum_value;
457 for (enum_value = enum_class->values; enum_value->value_name; enum_value++)
458 if (enum_value->value_nick && strcmp (nick, enum_value->value_nick) == 0)
466 * g_flags_get_value_by_nick:
467 * @flags_class: a #GFlagsClass
468 * @nick: the nickname to look up
470 * Looks up a #GFlagsValue by nickname.
472 * Returns: (transfer none): the #GFlagsValue with nickname @nick,
473 * or %NULL if there is no flag with that nickname
476 g_flags_get_value_by_nick (GFlagsClass *flags_class,
479 g_return_val_if_fail (G_IS_FLAGS_CLASS (flags_class), NULL);
480 g_return_val_if_fail (nick != NULL, NULL);
482 if (flags_class->n_values)
484 GFlagsValue *flags_value;
486 for (flags_value = flags_class->values; flags_value->value_nick; flags_value++)
487 if (flags_value->value_nick && strcmp (nick, flags_value->value_nick) == 0)
496 * @enum_class: a #GEnumClass
497 * @value: the value to look up
499 * Returns the #GEnumValue for a value.
501 * Returns: (transfer none): the #GEnumValue for @value, or %NULL
502 * if @value is not a member of the enumeration
505 g_enum_get_value (GEnumClass *enum_class,
508 g_return_val_if_fail (G_IS_ENUM_CLASS (enum_class), NULL);
510 if (enum_class->n_values)
512 GEnumValue *enum_value;
514 for (enum_value = enum_class->values; enum_value->value_name; enum_value++)
515 if (enum_value->value == value)
523 * g_flags_get_first_value:
524 * @flags_class: a #GFlagsClass
527 * Returns the first #GFlagsValue which is set in @value.
529 * Returns: (transfer none): the first #GFlagsValue which is set in
530 * @value, or %NULL if none is set
533 g_flags_get_first_value (GFlagsClass *flags_class,
536 g_return_val_if_fail (G_IS_FLAGS_CLASS (flags_class), NULL);
538 if (flags_class->n_values)
540 GFlagsValue *flags_value;
544 for (flags_value = flags_class->values; flags_value->value_name; flags_value++)
545 if (flags_value->value == 0)
550 for (flags_value = flags_class->values; flags_value->value_name; flags_value++)
551 if (flags_value->value != 0 && (flags_value->value & value) == flags_value->value)
561 * @value: a valid #GValue whose type is derived from %G_TYPE_ENUM
562 * @v_enum: enum value to be set
564 * Set the contents of a %G_TYPE_ENUM #GValue to @v_enum.
567 g_value_set_enum (GValue *value,
570 g_return_if_fail (G_VALUE_HOLDS_ENUM (value));
572 value->data[0].v_long = v_enum;
577 * @value: a valid #GValue whose type is derived from %G_TYPE_ENUM
579 * Get the contents of a %G_TYPE_ENUM #GValue.
581 * Returns: enum contents of @value
584 g_value_get_enum (const GValue *value)
586 g_return_val_if_fail (G_VALUE_HOLDS_ENUM (value), 0);
588 return value->data[0].v_long;
593 * @value: a valid #GValue whose type is derived from %G_TYPE_FLAGS
594 * @v_flags: flags value to be set
596 * Set the contents of a %G_TYPE_FLAGS #GValue to @v_flags.
599 g_value_set_flags (GValue *value,
602 g_return_if_fail (G_VALUE_HOLDS_FLAGS (value));
604 value->data[0].v_ulong = v_flags;
609 * @value: a valid #GValue whose type is derived from %G_TYPE_FLAGS
611 * Get the contents of a %G_TYPE_FLAGS #GValue.
613 * Returns: flags contents of @value
616 g_value_get_flags (const GValue *value)
618 g_return_val_if_fail (G_VALUE_HOLDS_FLAGS (value), 0);
620 return value->data[0].v_ulong;