1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
4 * gdataset.c: Generic dataset mechanism, similar to GtkObject data.
5 * Copyright (C) 1998 Tim Janik
7 * SPDX-License-Identifier: LGPL-2.1-or-later
9 * This library is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
24 * Modified by the GLib Team and others 1997-2000. See the AUTHORS
25 * file for a list of people on the GLib Team. See the ChangeLog
26 * files for a list of changes. These files are distributed with
27 * GLib at ftp://ftp.gtk.org/pub/gtk/.
31 * MT safe ; except for g_data*_foreach()
42 #include "gdatasetprivate.h"
45 #include "gstrfuncs.h"
46 #include "gtestutils.h"
48 #include "glib_trace.h"
54 * @short_description: associate groups of data elements with
55 * particular memory locations
57 * Datasets associate groups of data elements with particular memory
58 * locations. These are useful if you need to associate data with a
59 * structure returned from an external library. Since you cannot modify
60 * the structure, you use its location in memory as the key into a
61 * dataset, where you can associate any number of data elements with it.
63 * There are two forms of most of the dataset functions. The first form
64 * uses strings to identify the data elements associated with a
65 * location. The second form uses #GQuark identifiers, which are
66 * created with a call to g_quark_from_string() or
67 * g_quark_from_static_string(). The second form is quicker, since it
68 * does not require looking up the string in the hash table of #GQuark
71 * There is no function to create a dataset. It is automatically
72 * created as soon as you add elements to it.
74 * To add data elements to a dataset use g_dataset_id_set_data(),
75 * g_dataset_id_set_data_full(), g_dataset_set_data() and
76 * g_dataset_set_data_full().
78 * To get data elements from a dataset use g_dataset_id_get_data() and
79 * g_dataset_get_data().
81 * To iterate over all data elements in a dataset use
82 * g_dataset_foreach() (not thread-safe).
84 * To remove data elements from a dataset use
85 * g_dataset_id_remove_data() and g_dataset_remove_data().
87 * To destroy a dataset, use g_dataset_destroy().
92 * @title: Keyed Data Lists
93 * @short_description: lists of data elements which are accessible by a
94 * string or GQuark identifier
96 * Keyed data lists provide lists of arbitrary data elements which can
97 * be accessed either with a string or with a #GQuark corresponding to
100 * The #GQuark methods are quicker, since the strings have to be
101 * converted to #GQuarks anyway.
103 * Data lists are used for associating arbitrary data with #GObjects,
104 * using g_object_set_data() and related functions.
106 * To create a datalist, use g_datalist_init().
108 * To add data elements to a datalist use g_datalist_id_set_data(),
109 * g_datalist_id_set_data_full(), g_datalist_set_data() and
110 * g_datalist_set_data_full().
112 * To get data elements from a datalist use g_datalist_id_get_data()
113 * and g_datalist_get_data().
115 * To iterate over all data elements in a datalist use
116 * g_datalist_foreach() (not thread-safe).
118 * To remove data elements from a datalist use
119 * g_datalist_id_remove_data() and g_datalist_remove_data().
121 * To remove all data elements from a datalist, use g_datalist_clear().
127 * An opaque data structure that represents a keyed data list.
129 * See also: [Keyed data lists][glib-Keyed-Data-Lists].
134 * @data: the data element.
136 * Specifies the type of function which is called when a data element
137 * is destroyed. It is passed the pointer to the data element and
138 * should free any memory and resources allocated for it.
141 #define G_DATALIST_FLAGS_MASK_INTERNAL 0x7
143 /* datalist pointer accesses have to be carried out atomically */
144 #define G_DATALIST_GET_POINTER(datalist) \
145 ((GData*) ((gsize) g_atomic_pointer_get (datalist) & ~(gsize) G_DATALIST_FLAGS_MASK_INTERNAL))
147 #define G_DATALIST_SET_POINTER(datalist, pointer) G_STMT_START { \
148 gpointer _oldv = g_atomic_pointer_get (datalist); \
151 _newv = (gpointer) (((gsize) _oldv & G_DATALIST_FLAGS_MASK_INTERNAL) | (gsize) pointer); \
152 } while (!g_atomic_pointer_compare_and_exchange_full ((void**) datalist, _oldv, \
156 /* --- structures --- */
160 GDestroyNotify destroy;
163 typedef struct _GDataset GDataset;
166 guint32 len; /* Number of elements */
167 guint32 alloc; /* Number of allocated elements */
168 GDataElt data[1]; /* Flexible array */
173 gconstpointer location;
178 /* --- prototypes --- */
179 static inline GDataset* g_dataset_lookup (gconstpointer dataset_location);
180 static inline void g_datalist_clear_i (GData **datalist);
181 static void g_dataset_destroy_internal (GDataset *dataset);
182 static inline gpointer g_data_set_internal (GData **datalist,
185 GDestroyNotify destroy_func,
187 static void g_data_initialize (void);
190 * Each standalone GDataList is protected by a bitlock in the datalist pointer,
191 * which protects that modification of the non-flags part of the datalist pointer
192 * and the contents of the datalist.
194 * For GDataSet we have a global lock g_dataset_global that protects
195 * the global dataset hash and cache, and additionally it protects the
196 * datalist such that we can avoid to use the bit lock in a few places
200 /* --- variables --- */
201 G_LOCK_DEFINE_STATIC (g_dataset_global);
202 static GHashTable *g_dataset_location_ht = NULL;
203 static GDataset *g_dataset_cached = NULL; /* should this be
206 /* --- functions --- */
208 #define DATALIST_LOCK_BIT 2
211 g_datalist_lock (GData **datalist)
213 g_pointer_bit_lock ((void **)datalist, DATALIST_LOCK_BIT);
217 g_datalist_unlock (GData **datalist)
219 g_pointer_bit_unlock ((void **)datalist, DATALIST_LOCK_BIT);
222 /* Called with the datalist lock held, or the dataset global
223 * lock for dataset lists
226 g_datalist_clear_i (GData **datalist)
231 data = G_DATALIST_GET_POINTER (datalist);
232 G_DATALIST_SET_POINTER (datalist, NULL);
236 G_UNLOCK (g_dataset_global);
237 for (i = 0; i < data->len; i++)
239 if (data->data[i].data && data->data[i].destroy)
240 data->data[i].destroy (data->data[i].data);
242 G_LOCK (g_dataset_global);
250 * g_datalist_clear: (skip)
251 * @datalist: a datalist.
253 * Frees all the data elements of the datalist.
254 * The data elements' destroy functions are called
255 * if they have been set.
258 g_datalist_clear (GData **datalist)
263 g_return_if_fail (datalist != NULL);
265 g_datalist_lock (datalist);
267 data = G_DATALIST_GET_POINTER (datalist);
268 G_DATALIST_SET_POINTER (datalist, NULL);
270 g_datalist_unlock (datalist);
274 for (i = 0; i < data->len; i++)
276 if (data->data[i].data && data->data[i].destroy)
277 data->data[i].destroy (data->data[i].data);
284 /* HOLDS: g_dataset_global_lock */
285 static inline GDataset*
286 g_dataset_lookup (gconstpointer dataset_location)
290 if (g_dataset_cached && g_dataset_cached->location == dataset_location)
291 return g_dataset_cached;
293 dataset = g_hash_table_lookup (g_dataset_location_ht, dataset_location);
295 g_dataset_cached = dataset;
300 /* HOLDS: g_dataset_global_lock */
302 g_dataset_destroy_internal (GDataset *dataset)
304 gconstpointer dataset_location;
306 dataset_location = dataset->location;
309 if (G_DATALIST_GET_POINTER(&dataset->datalist) == NULL)
311 if (dataset == g_dataset_cached)
312 g_dataset_cached = NULL;
313 g_hash_table_remove (g_dataset_location_ht, dataset_location);
314 g_slice_free (GDataset, dataset);
318 g_datalist_clear_i (&dataset->datalist);
319 dataset = g_dataset_lookup (dataset_location);
325 * @dataset_location: (not nullable): the location identifying the dataset.
327 * Destroys the dataset, freeing all memory allocated, and calling any
328 * destroy functions set for data elements.
331 g_dataset_destroy (gconstpointer dataset_location)
333 g_return_if_fail (dataset_location != NULL);
335 G_LOCK (g_dataset_global);
336 if (g_dataset_location_ht)
340 dataset = g_dataset_lookup (dataset_location);
342 g_dataset_destroy_internal (dataset);
344 G_UNLOCK (g_dataset_global);
347 /* HOLDS: g_dataset_global_lock if dataset != null */
348 static inline gpointer
349 g_data_set_internal (GData **datalist,
352 GDestroyNotify new_destroy_func,
356 GDataElt old, *data, *data_last, *data_end;
358 g_datalist_lock (datalist);
360 d = G_DATALIST_GET_POINTER (datalist);
362 if (new_data == NULL) /* remove */
367 data_last = data + d->len - 1;
368 while (data <= data_last)
370 if (data->key == key_id)
373 if (data != data_last)
377 /* We don't bother to shrink, but if all data are now gone
378 * we at least free the memory
382 G_DATALIST_SET_POINTER (datalist, NULL);
384 /* datalist may be situated in dataset, so must not be
385 * unlocked after we free it
387 g_datalist_unlock (datalist);
389 /* the dataset destruction *must* be done
390 * prior to invocation of the data destroy function
393 g_dataset_destroy_internal (dataset);
397 g_datalist_unlock (datalist);
400 /* We found and removed an old value
401 * the GData struct *must* already be unlinked
402 * when invoking the destroy function.
403 * we use (new_data==NULL && new_destroy_func!=NULL) as
404 * a special hint combination to "steal"
405 * data without destroy notification
407 if (old.destroy && !new_destroy_func)
410 G_UNLOCK (g_dataset_global);
411 old.destroy (old.data);
413 G_LOCK (g_dataset_global);
429 data_end = data + d->len;
430 while (data < data_end)
432 if (data->key == key_id)
436 data->data = new_data;
437 data->destroy = new_destroy_func;
438 g_datalist_unlock (datalist);
443 data->data = new_data;
444 data->destroy = new_destroy_func;
446 g_datalist_unlock (datalist);
448 /* We found and replaced an old value
449 * the GData struct *must* already be unlinked
450 * when invoking the destroy function.
453 G_UNLOCK (g_dataset_global);
454 old.destroy (old.data);
456 G_LOCK (g_dataset_global);
464 /* The key was not found, insert it */
468 d = g_malloc (sizeof (GData));
472 else if (d->len == d->alloc)
474 d->alloc = d->alloc * 2;
475 d = g_realloc (d, sizeof (GData) + (d->alloc - 1) * sizeof (GDataElt));
478 G_DATALIST_SET_POINTER (datalist, d);
480 d->data[d->len].key = key_id;
481 d->data[d->len].data = new_data;
482 d->data[d->len].destroy = new_destroy_func;
486 g_datalist_unlock (datalist);
493 g_data_remove_internal (GData **datalist,
499 g_datalist_lock (datalist);
501 d = G_DATALIST_GET_POINTER (datalist);
505 GDataElt *old, *data, *data_end;
508 /* Allocate an array of GDataElt to hold copies of the elements
509 * that are removed from the datalist. Allow enough space for all
510 * the keys; if a key is not found, the corresponding element of
511 * old is not populated, so we initialize them all to NULL to
512 * detect that case. */
513 old = g_newa0 (GDataElt, n_keys);
516 data_end = data + d->len;
519 while (data < data_end && found_keys < n_keys)
521 gboolean remove = FALSE;
523 for (gsize i = 0; i < n_keys; i++)
525 if (data->key == keys[i])
535 GDataElt *data_last = data_end - 1;
539 if (data < data_last)
545 /* We don't bother to shrink, but if all data are now gone
546 * we at least free the memory
550 G_DATALIST_SET_POINTER (datalist, NULL);
563 g_datalist_unlock (datalist);
565 for (gsize i = 0; i < n_keys; i++)
567 /* If keys[i] was not found, then old[i].destroy is NULL.
568 * Call old[i].destroy() only if keys[i] was found, and
569 * is associated with a destroy notifier: */
571 old[i].destroy (old[i].data);
578 g_datalist_unlock (datalist);
582 * g_dataset_id_set_data_full: (skip)
583 * @dataset_location: (not nullable): the location identifying the dataset.
584 * @key_id: the #GQuark id to identify the data element.
585 * @data: the data element.
586 * @destroy_func: the function to call when the data element is
587 * removed. This function will be called with the data
588 * element and can be used to free any memory allocated
591 * Sets the data element associated with the given #GQuark id, and also
592 * the function to call when the data element is destroyed. Any
593 * previous data with the same key is removed, and its destroy function
597 * g_dataset_set_data_full: (skip)
598 * @l: the location identifying the dataset.
599 * @k: the string to identify the data element.
600 * @d: the data element.
601 * @f: the function to call when the data element is removed. This
602 * function will be called with the data element and can be used to
603 * free any memory allocated for it.
605 * Sets the data corresponding to the given string identifier, and the
606 * function to call when the data element is destroyed.
609 * g_dataset_id_set_data:
610 * @l: the location identifying the dataset.
611 * @k: the #GQuark id to identify the data element.
612 * @d: the data element.
614 * Sets the data element associated with the given #GQuark id. Any
615 * previous data with the same key is removed, and its destroy function
619 * g_dataset_set_data:
620 * @l: the location identifying the dataset.
621 * @k: the string to identify the data element.
622 * @d: the data element.
624 * Sets the data corresponding to the given string identifier.
627 * g_dataset_id_remove_data:
628 * @l: the location identifying the dataset.
629 * @k: the #GQuark id identifying the data element.
631 * Removes a data element from a dataset. The data element's destroy
632 * function is called if it has been set.
635 * g_dataset_remove_data:
636 * @l: the location identifying the dataset.
637 * @k: the string identifying the data element.
639 * Removes a data element corresponding to a string. Its destroy
640 * function is called if it has been set.
643 g_dataset_id_set_data_full (gconstpointer dataset_location,
646 GDestroyNotify destroy_func)
650 g_return_if_fail (dataset_location != NULL);
652 g_return_if_fail (destroy_func == NULL);
656 g_return_if_fail (key_id > 0);
661 G_LOCK (g_dataset_global);
662 if (!g_dataset_location_ht)
663 g_data_initialize ();
665 dataset = g_dataset_lookup (dataset_location);
668 dataset = g_slice_new (GDataset);
669 dataset->location = dataset_location;
670 g_datalist_init (&dataset->datalist);
671 g_hash_table_insert (g_dataset_location_ht,
672 (gpointer) dataset->location,
676 g_data_set_internal (&dataset->datalist, key_id, data, destroy_func, dataset);
677 G_UNLOCK (g_dataset_global);
681 * g_datalist_id_set_data_full: (skip)
682 * @datalist: a datalist.
683 * @key_id: the #GQuark to identify the data element.
684 * @data: (nullable): the data element or %NULL to remove any previous element
685 * corresponding to @key_id.
686 * @destroy_func: (nullable): the function to call when the data element is
687 * removed. This function will be called with the data
688 * element and can be used to free any memory allocated
689 * for it. If @data is %NULL, then @destroy_func must
692 * Sets the data corresponding to the given #GQuark id, and the
693 * function to be called when the element is removed from the datalist.
694 * Any previous data with the same key is removed, and its destroy
695 * function is called.
698 * g_datalist_set_data_full: (skip)
700 * @k: the string to identify the data element.
701 * @d: (nullable): the data element, or %NULL to remove any previous element
702 * corresponding to @k.
703 * @f: (nullable): the function to call when the data element is removed.
704 * This function will be called with the data element and can be used to
705 * free any memory allocated for it. If @d is %NULL, then @f must
708 * Sets the data element corresponding to the given string identifier,
709 * and the function to be called when the data element is removed.
712 * g_datalist_id_set_data:
714 * @q: the #GQuark to identify the data element.
715 * @d: (nullable): the data element, or %NULL to remove any previous element
716 * corresponding to @q.
718 * Sets the data corresponding to the given #GQuark id. Any previous
719 * data with the same key is removed, and its destroy function is
723 * g_datalist_set_data:
725 * @k: the string to identify the data element.
726 * @d: (nullable): the data element, or %NULL to remove any previous element
727 * corresponding to @k.
729 * Sets the data element corresponding to the given string identifier.
732 * g_datalist_id_remove_data:
734 * @q: the #GQuark identifying the data element.
736 * Removes an element, using its #GQuark identifier.
739 * g_datalist_remove_data:
741 * @k: the string identifying the data element.
743 * Removes an element using its string identifier. The data element's
744 * destroy function is called if it has been set.
747 g_datalist_id_set_data_full (GData **datalist,
750 GDestroyNotify destroy_func)
752 g_return_if_fail (datalist != NULL);
754 g_return_if_fail (destroy_func == NULL);
758 g_return_if_fail (key_id > 0);
763 g_data_set_internal (datalist, key_id, data, destroy_func, NULL);
767 * g_datalist_id_remove_multiple:
768 * @datalist: a datalist
769 * @keys: (array length=n_keys): keys to remove
770 * @n_keys: length of @keys, must be <= 16
772 * Removes multiple keys from a datalist.
774 * This is more efficient than calling g_datalist_id_remove_data()
775 * multiple times in a row.
780 g_datalist_id_remove_multiple (GData **datalist,
784 g_return_if_fail (n_keys <= 16);
786 g_data_remove_internal (datalist, keys, n_keys);
790 * g_dataset_id_remove_no_notify: (skip)
791 * @dataset_location: (not nullable): the location identifying the dataset.
792 * @key_id: the #GQuark ID identifying the data element.
794 * Removes an element, without calling its destroy notification
797 * Returns: (nullable): the data previously stored at @key_id,
801 * g_dataset_remove_no_notify: (skip)
802 * @l: the location identifying the dataset.
803 * @k: the string identifying the data element.
805 * Removes an element, without calling its destroy notifier.
808 g_dataset_id_remove_no_notify (gconstpointer dataset_location,
811 gpointer ret_data = NULL;
813 g_return_val_if_fail (dataset_location != NULL, NULL);
815 G_LOCK (g_dataset_global);
816 if (key_id && g_dataset_location_ht)
820 dataset = g_dataset_lookup (dataset_location);
822 ret_data = g_data_set_internal (&dataset->datalist, key_id, NULL, (GDestroyNotify) 42, dataset);
824 G_UNLOCK (g_dataset_global);
830 * g_datalist_id_remove_no_notify: (skip)
831 * @datalist: a datalist.
832 * @key_id: the #GQuark identifying a data element.
834 * Removes an element, without calling its destroy notification
837 * Returns: (nullable): the data previously stored at @key_id,
841 * g_datalist_remove_no_notify: (skip)
843 * @k: the string identifying the data element.
845 * Removes an element, without calling its destroy notifier.
848 g_datalist_id_remove_no_notify (GData **datalist,
851 gpointer ret_data = NULL;
853 g_return_val_if_fail (datalist != NULL, NULL);
856 ret_data = g_data_set_internal (datalist, key_id, NULL, (GDestroyNotify) 42, NULL);
862 * g_dataset_id_get_data:
863 * @dataset_location: (not nullable): the location identifying the dataset.
864 * @key_id: the #GQuark id to identify the data element.
866 * Gets the data element corresponding to a #GQuark.
868 * Returns: (transfer none) (nullable): the data element corresponding to
869 * the #GQuark, or %NULL if it is not found.
872 * g_dataset_get_data:
873 * @l: the location identifying the dataset.
874 * @k: the string identifying the data element.
876 * Gets the data element corresponding to a string.
878 * Returns: (transfer none) (nullable): the data element corresponding to
879 * the string, or %NULL if it is not found.
882 g_dataset_id_get_data (gconstpointer dataset_location,
885 gpointer retval = NULL;
887 g_return_val_if_fail (dataset_location != NULL, NULL);
889 G_LOCK (g_dataset_global);
890 if (key_id && g_dataset_location_ht)
894 dataset = g_dataset_lookup (dataset_location);
896 retval = g_datalist_id_get_data (&dataset->datalist, key_id);
898 G_UNLOCK (g_dataset_global);
904 * g_datalist_id_get_data:
905 * @datalist: a datalist.
906 * @key_id: the #GQuark identifying a data element.
908 * Retrieves the data element corresponding to @key_id.
910 * Returns: (transfer none) (nullable): the data element, or %NULL if
914 g_datalist_id_get_data (GData **datalist,
917 return g_datalist_id_dup_data (datalist, key_id, NULL, NULL);
922 * @data: the data to duplicate
923 * @user_data: (closure): user data that was specified in
924 * g_datalist_id_dup_data()
926 * The type of functions that are used to 'duplicate' an object.
927 * What this means depends on the context, it could just be
928 * incrementing the reference count, if @data is a ref-counted
931 * Returns: a duplicate of data
935 * g_datalist_id_dup_data: (skip)
936 * @datalist: location of a datalist
937 * @key_id: the #GQuark identifying a data element
938 * @dup_func: (scope call) (closure user_data) (nullable): function to
939 * duplicate the old value
940 * @user_data: passed as user_data to @dup_func
942 * This is a variant of g_datalist_id_get_data() which
943 * returns a 'duplicate' of the value. @dup_func defines the
944 * meaning of 'duplicate' in this context, it could e.g.
945 * take a reference on a ref-counted object.
947 * If the @key_id is not set in the datalist then @dup_func
948 * will be called with a %NULL argument.
950 * Note that @dup_func is called while the datalist is locked, so it
951 * is not allowed to read or modify the datalist.
953 * This function can be useful to avoid races when multiple
954 * threads are using the same datalist and the same key.
956 * Returns: (nullable): the result of calling @dup_func on the value
957 * associated with @key_id in @datalist, or %NULL if not set.
958 * If @dup_func is %NULL, the value is returned unmodified.
963 g_datalist_id_dup_data (GData **datalist,
965 GDuplicateFunc dup_func,
969 gpointer retval = NULL;
971 GDataElt *data, *data_end;
973 g_datalist_lock (datalist);
975 d = G_DATALIST_GET_POINTER (datalist);
979 data_end = data + d->len;
982 if (data->key == key_id)
989 while (data < data_end);
993 retval = dup_func (val, user_data);
997 g_datalist_unlock (datalist);
1003 * g_datalist_id_replace_data: (skip)
1004 * @datalist: location of a datalist
1005 * @key_id: the #GQuark identifying a data element
1006 * @oldval: (nullable): the old value to compare against
1007 * @newval: (nullable): the new value to replace it with
1008 * @destroy: (nullable): destroy notify for the new value
1009 * @old_destroy: (out) (optional): destroy notify for the existing value
1011 * Compares the member that is associated with @key_id in
1012 * @datalist to @oldval, and if they are the same, replace
1013 * @oldval with @newval.
1015 * This is like a typical atomic compare-and-exchange
1016 * operation, for a member of @datalist.
1018 * If the previous value was replaced then ownership of the
1019 * old value (@oldval) is passed to the caller, including
1020 * the registered destroy notify for it (passed out in @old_destroy).
1021 * Its up to the caller to free this as they wish, which may
1022 * or may not include using @old_destroy as sometimes replacement
1023 * should not destroy the object in the normal way.
1025 * Returns: %TRUE if the existing value for @key_id was replaced
1026 * by @newval, %FALSE otherwise.
1031 g_datalist_id_replace_data (GData **datalist,
1035 GDestroyNotify destroy,
1036 GDestroyNotify *old_destroy)
1038 gpointer val = NULL;
1040 GDataElt *data, *data_end;
1042 g_return_val_if_fail (datalist != NULL, FALSE);
1043 g_return_val_if_fail (key_id != 0, FALSE);
1046 *old_destroy = NULL;
1048 g_datalist_lock (datalist);
1050 d = G_DATALIST_GET_POINTER (datalist);
1054 data_end = data + d->len - 1;
1055 while (data <= data_end)
1057 if (data->key == key_id)
1063 *old_destroy = data->destroy;
1066 data->data = newval;
1067 data->destroy = destroy;
1071 if (data != data_end)
1075 /* We don't bother to shrink, but if all data are now gone
1076 * we at least free the memory
1080 G_DATALIST_SET_POINTER (datalist, NULL);
1091 if (val == NULL && oldval == NULL && newval != NULL)
1099 d = g_malloc (sizeof (GData));
1103 else if (d->len == d->alloc)
1105 d->alloc = d->alloc * 2;
1106 d = g_realloc (d, sizeof (GData) + (d->alloc - 1) * sizeof (GDataElt));
1109 G_DATALIST_SET_POINTER (datalist, d);
1111 d->data[d->len].key = key_id;
1112 d->data[d->len].data = newval;
1113 d->data[d->len].destroy = destroy;
1117 g_datalist_unlock (datalist);
1119 return val == oldval;
1123 * g_datalist_get_data:
1124 * @datalist: a datalist.
1125 * @key: the string identifying a data element.
1127 * Gets a data element, using its string identifier. This is slower than
1128 * g_datalist_id_get_data() because it compares strings.
1130 * Returns: (transfer none) (nullable): the data element, or %NULL if it
1134 g_datalist_get_data (GData **datalist,
1137 gpointer res = NULL;
1139 GDataElt *data, *data_end;
1141 g_return_val_if_fail (datalist != NULL, NULL);
1143 g_datalist_lock (datalist);
1145 d = G_DATALIST_GET_POINTER (datalist);
1149 data_end = data + d->len;
1150 while (data < data_end)
1152 if (g_strcmp0 (g_quark_to_string (data->key), key) == 0)
1161 g_datalist_unlock (datalist);
1168 * @key_id: the #GQuark id to identifying the data element.
1169 * @data: the data element.
1170 * @user_data: (closure): user data passed to g_dataset_foreach().
1172 * Specifies the type of function passed to g_dataset_foreach(). It is
1173 * called with each #GQuark id and associated data element, together
1174 * with the @user_data parameter supplied to g_dataset_foreach().
1178 * g_dataset_foreach:
1179 * @dataset_location: (not nullable): the location identifying the dataset.
1180 * @func: (scope call) (closure user_data): the function to call for each data element.
1181 * @user_data: user data to pass to the function.
1183 * Calls the given function for each data element which is associated
1184 * with the given location. Note that this function is NOT thread-safe.
1185 * So unless @dataset_location can be protected from any modifications
1186 * during invocation of this function, it should not be called.
1188 * @func can make changes to the dataset, but the iteration will not
1189 * reflect changes made during the g_dataset_foreach() call, other
1190 * than skipping over elements that are removed.
1193 g_dataset_foreach (gconstpointer dataset_location,
1194 GDataForeachFunc func,
1199 g_return_if_fail (dataset_location != NULL);
1200 g_return_if_fail (func != NULL);
1202 G_LOCK (g_dataset_global);
1203 if (g_dataset_location_ht)
1205 dataset = g_dataset_lookup (dataset_location);
1206 G_UNLOCK (g_dataset_global);
1208 g_datalist_foreach (&dataset->datalist, func, user_data);
1212 G_UNLOCK (g_dataset_global);
1217 * g_datalist_foreach:
1218 * @datalist: a datalist.
1219 * @func: (scope call) (closure user_data): the function to call for each data element.
1220 * @user_data: user data to pass to the function.
1222 * Calls the given function for each data element of the datalist. The
1223 * function is called with each data element's #GQuark id and data,
1224 * together with the given @user_data parameter. Note that this
1225 * function is NOT thread-safe. So unless @datalist can be protected
1226 * from any modifications during invocation of this function, it should
1229 * @func can make changes to @datalist, but the iteration will not
1230 * reflect changes made during the g_datalist_foreach() call, other
1231 * than skipping over elements that are removed.
1234 g_datalist_foreach (GData **datalist,
1235 GDataForeachFunc func,
1242 g_return_if_fail (datalist != NULL);
1243 g_return_if_fail (func != NULL);
1245 d = G_DATALIST_GET_POINTER (datalist);
1249 /* We make a copy of the keys so that we can handle it changing
1252 keys = g_new (GQuark, len);
1253 for (i = 0; i < len; i++)
1254 keys[i] = d->data[i].key;
1256 for (i = 0; i < len; i++)
1258 /* A previous callback might have removed a later item, so always check that
1259 it still exists before calling */
1260 d = G_DATALIST_GET_POINTER (datalist);
1264 for (j = 0; j < d->len; j++)
1266 if (d->data[j].key == keys[i]) {
1267 func (d->data[i].key, d->data[i].data, user_data);
1276 * g_datalist_init: (skip)
1277 * @datalist: a pointer to a pointer to a datalist.
1279 * Resets the datalist to %NULL. It does not free any memory or call
1280 * any destroy functions.
1283 g_datalist_init (GData **datalist)
1285 g_return_if_fail (datalist != NULL);
1287 g_atomic_pointer_set (datalist, NULL);
1291 * g_datalist_set_flags:
1292 * @datalist: pointer to the location that holds a list
1293 * @flags: the flags to turn on. The values of the flags are
1294 * restricted by %G_DATALIST_FLAGS_MASK (currently
1295 * 3; giving two possible boolean flags).
1296 * A value for @flags that doesn't fit within the mask is
1299 * Turns on flag values for a data list. This function is used
1300 * to keep a small number of boolean flags in an object with
1301 * a data list without using any additional space. It is
1302 * not generally useful except in circumstances where space
1303 * is very tight. (It is used in the base #GObject type, for
1309 g_datalist_set_flags (GData **datalist,
1312 g_return_if_fail (datalist != NULL);
1313 g_return_if_fail ((flags & ~G_DATALIST_FLAGS_MASK) == 0);
1315 g_atomic_pointer_or (datalist, (gsize)flags);
1319 * g_datalist_unset_flags:
1320 * @datalist: pointer to the location that holds a list
1321 * @flags: the flags to turn off. The values of the flags are
1322 * restricted by %G_DATALIST_FLAGS_MASK (currently
1323 * 3: giving two possible boolean flags).
1324 * A value for @flags that doesn't fit within the mask is
1327 * Turns off flag values for a data list. See g_datalist_unset_flags()
1332 g_datalist_unset_flags (GData **datalist,
1335 g_return_if_fail (datalist != NULL);
1336 g_return_if_fail ((flags & ~G_DATALIST_FLAGS_MASK) == 0);
1338 g_atomic_pointer_and (datalist, ~(gsize)flags);
1342 * g_datalist_get_flags:
1343 * @datalist: pointer to the location that holds a list
1345 * Gets flags values packed in together with the datalist.
1346 * See g_datalist_set_flags().
1348 * Returns: the flags of the datalist
1353 g_datalist_get_flags (GData **datalist)
1355 g_return_val_if_fail (datalist != NULL, 0);
1357 return G_DATALIST_GET_FLAGS (datalist); /* atomic macro */
1360 /* HOLDS: g_dataset_global_lock */
1362 g_data_initialize (void)
1364 g_return_if_fail (g_dataset_location_ht == NULL);
1366 g_dataset_location_ht = g_hash_table_new (g_direct_hash, NULL);
1367 g_dataset_cached = NULL;