1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
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 Public
15 * 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.
21 * Modified by the GLib Team and others 1997-2000. See the AUTHORS
22 * file for a list of people on the GLib Team. See the ChangeLog
23 * files for a list of changes. These files are distributed with
24 * GLib at ftp://ftp.gtk.org/pub/gtk/.
36 #include "gtestutils.h"
39 * SECTION:linked_lists_double
40 * @title: Doubly-Linked Lists
41 * @short_description: linked lists that can be iterated over in both directions
43 * The #GList structure and its associated functions provide a standard
44 * doubly-linked list data structure.
46 * Each element in the list contains a piece of data, together with
47 * pointers which link to the previous and next elements in the list.
48 * Using these pointers it is possible to move through the list in both
49 * directions (unlike the <link
50 * linkend="glib-Singly-Linked-Lists">Singly-Linked Lists</link> which
51 * only allows movement through the list in the forward direction).
53 * The data contained in each element can be either integer values, by
54 * using one of the <link linkend="glib-Type-Conversion-Macros">Type
55 * Conversion Macros</link>, or simply pointers to any type of data.
57 * List elements are allocated from the <link
58 * linkend="glib-Memory-Slices">slice allocator</link>, which is more
59 * efficient than allocating elements individually.
61 * Note that most of the #GList functions expect to be passed a pointer
62 * to the first element in the list. The functions which insert
63 * elements return the new start of the list, which may have changed.
65 * There is no function to create a #GList. %NULL is considered to be
66 * the empty list so you simply set a #GList* to %NULL.
68 * To add elements, use g_list_append(), g_list_prepend(),
69 * g_list_insert() and g_list_insert_sorted().
71 * To remove elements, use g_list_remove().
73 * To find elements in the list use g_list_first(), g_list_last(),
74 * g_list_next(), g_list_previous(), g_list_nth(), g_list_nth_data(),
75 * g_list_find() and g_list_find_custom().
77 * To find the index of an element use g_list_position() and
80 * To call a function for each element in the list use g_list_foreach().
82 * To free the entire list, use g_list_free().
87 * @data: holds the element's data, which can be a pointer to any kind
88 * of data, or any integer value using the <link
89 * linkend="glib-Type-Conversion-Macros">Type Conversion
91 * @next: contains the link to the next element in the list.
92 * @prev: contains the link to the previous element in the list.
94 * The #GList struct is used for each element in a doubly-linked list.
99 * @list: an element in a #GList.
101 * A convenience macro to get the previous element in a #GList.
103 * Returns: the previous element, or %NULL if there are no previous
109 * @list: an element in a #GList.
111 * A convenience macro to get the next element in a #GList.
113 * Returns: the next element, or %NULL if there are no more elements.
116 #define _g_list_alloc() g_slice_new (GList)
117 #define _g_list_alloc0() g_slice_new0 (GList)
118 #define _g_list_free1(list) g_slice_free (GList, list)
123 * Allocates space for one #GList element. It is called by
124 * g_list_append(), g_list_prepend(), g_list_insert() and
125 * g_list_insert_sorted() and so is rarely used on its own.
127 * Returns: a pointer to the newly-allocated #GList element.
132 return _g_list_alloc0 ();
139 * Frees all of the memory used by a #GList.
140 * The freed elements are returned to the slice allocator.
143 * If list elements contain dynamically-allocated memory,
144 * you should either use g_list_free_full() or free them manually
149 g_list_free (GList *list)
151 g_slice_free_chain (GList, list, next);
156 * @list: a #GList element
158 * Frees one #GList element.
159 * It is usually used after g_list_remove_link().
164 * Another name for g_list_free_1().
167 g_list_free_1 (GList *list)
169 _g_list_free1 (list);
174 * @list: a pointer to a #GList
175 * @free_func: the function to be called to free each element's data
177 * Convenience method, which frees all the memory used by a #GList, and
178 * calls the specified destroy function on every element's data.
183 g_list_free_full (GList *list,
184 GDestroyNotify free_func)
186 g_list_foreach (list, (GFunc) free_func, NULL);
192 * @list: a pointer to a #GList
193 * @data: the data for the new element
195 * Adds a new element on to the end of the list.
198 * The return value is the new start of the list, which
199 * may have changed, so make sure you store the new value.
203 * Note that g_list_append() has to traverse the entire list
204 * to find the end, which is inefficient when adding multiple
205 * elements. A common idiom to avoid the inefficiency is to prepend
206 * the elements and reverse the list when all elements have been added.
210 * /* Notice that these are initialized to the empty list. */
211 * GList *list = NULL, *number_list = NULL;
213 * /* This is a list of strings. */
214 * list = g_list_append (list, "first");
215 * list = g_list_append (list, "second");
217 * /* This is a list of integers. */
218 * number_list = g_list_append (number_list, GINT_TO_POINTER (27));
219 * number_list = g_list_append (number_list, GINT_TO_POINTER (14));
222 * Returns: the new start of the #GList
225 g_list_append (GList *list,
231 new_list = _g_list_alloc ();
232 new_list->data = data;
233 new_list->next = NULL;
237 last = g_list_last (list);
238 /* g_assert (last != NULL); */
239 last->next = new_list;
240 new_list->prev = last;
246 new_list->prev = NULL;
253 * @list: a pointer to a #GList
254 * @data: the data for the new element
256 * Adds a new element on to the start of the list.
259 * The return value is the new start of the list, which
260 * may have changed, so make sure you store the new value.
264 * /* Notice that it is initialized to the empty list. */
265 * GList *list = NULL;
266 * list = g_list_prepend (list, "last");
267 * list = g_list_prepend (list, "first");
270 * Returns: the new start of the #GList
273 g_list_prepend (GList *list,
278 new_list = _g_list_alloc ();
279 new_list->data = data;
280 new_list->next = list;
284 new_list->prev = list->prev;
286 list->prev->next = new_list;
287 list->prev = new_list;
290 new_list->prev = NULL;
297 * @list: a pointer to a #GList
298 * @data: the data for the new element
299 * @position: the position to insert the element. If this is
300 * negative, or is larger than the number of elements in the
301 * list, the new element is added on to the end of the list.
303 * Inserts a new element into the list at the given position.
305 * Returns: the new start of the #GList
308 g_list_insert (GList *list,
316 return g_list_append (list, data);
317 else if (position == 0)
318 return g_list_prepend (list, data);
320 tmp_list = g_list_nth (list, position);
322 return g_list_append (list, data);
324 new_list = _g_list_alloc ();
325 new_list->data = data;
326 new_list->prev = tmp_list->prev;
327 tmp_list->prev->next = new_list;
328 new_list->next = tmp_list;
329 tmp_list->prev = new_list;
335 * g_list_insert_before:
336 * @list: a pointer to a #GList
337 * @sibling: the list element before which the new element
338 * is inserted or %NULL to insert at the end of the list
339 * @data: the data for the new element
341 * Inserts a new element into the list before the given position.
343 * Returns: the new start of the #GList
346 g_list_insert_before (GList *list,
352 list = g_list_alloc ();
354 g_return_val_if_fail (sibling == NULL, list);
361 node = _g_list_alloc ();
363 node->prev = sibling->prev;
364 node->next = sibling;
365 sibling->prev = node;
368 node->prev->next = node;
373 g_return_val_if_fail (sibling == list, node);
385 last->next = _g_list_alloc ();
386 last->next->data = data;
387 last->next->prev = last;
388 last->next->next = NULL;
397 * @list2: the #GList to add to the end of the first #GList
399 * Adds the second #GList onto the end of the first #GList.
400 * Note that the elements of the second #GList are not copied.
401 * They are used directly.
403 * Returns: the start of the new #GList
406 g_list_concat (GList *list1, GList *list2)
412 tmp_list = g_list_last (list1);
414 tmp_list->next = list2;
417 list2->prev = tmp_list;
426 * @data: the data of the element to remove
428 * Removes an element from a #GList.
429 * If two elements contain the same data, only the first is removed.
430 * If none of the elements contain the data, the #GList is unchanged.
432 * Returns: the new start of the #GList
435 g_list_remove (GList *list,
443 if (tmp->data != data)
448 tmp->prev->next = tmp->next;
450 tmp->next->prev = tmp->prev;
466 * @data: data to remove
468 * Removes all list nodes with data equal to @data.
469 * Returns the new head of the list. Contrast with
470 * g_list_remove() which removes only the first node
471 * matching the given data.
473 * Returns: new head of @list
476 g_list_remove_all (GList *list,
483 if (tmp->data != data)
487 GList *next = tmp->next;
490 tmp->prev->next = next;
494 next->prev = tmp->prev;
504 _g_list_remove_link (GList *list,
510 link->prev->next = link->next;
512 link->next->prev = link->prev;
525 * g_list_remove_link:
527 * @llink: an element in the #GList
529 * Removes an element from a #GList, without freeing the element.
530 * The removed element's prev and next links are set to %NULL, so
531 * that it becomes a self-contained list with one element.
533 * Returns: the new start of the #GList, without the element
536 g_list_remove_link (GList *list,
539 return _g_list_remove_link (list, llink);
543 * g_list_delete_link:
545 * @link_: node to delete from @list
547 * Removes the node link_ from the list and frees it.
548 * Compare this to g_list_remove_link() which removes the node
549 * without freeing it.
551 * Returns: the new head of @list
554 g_list_delete_link (GList *list,
557 list = _g_list_remove_link (list, link_);
558 _g_list_free1 (link_);
570 * Note that this is a "shallow" copy. If the list elements
571 * consist of pointers to data, the pointers are copied but
572 * the actual data is not. See g_list_copy_deep() if you need
573 * to copy the data as well.
576 * Returns: a copy of @list
579 g_list_copy (GList *list)
581 return g_list_copy_deep (list, NULL, NULL);
587 * @func: a copy function used to copy every element in the list
588 * @user_data: user data passed to the copy function @func, or #NULL
590 * Makes a full (deep) copy of a #GList.
592 * In contrast with g_list_copy(), this function uses @func to make a copy of
593 * each list element, in addition to copying the list container itself.
595 * @func, as a #GCopyFunc, takes two arguments, the data to be copied and a user
596 * pointer. It's safe to pass #NULL as user_data, if the copy function takes only
599 * For instance, if @list holds a list of GObjects, you can do:
601 * another_list = g_list_copy_deep (list, (GCopyFunc) g_object_ref, NULL);
604 * And, to entirely free the new list, you could do:
606 * g_list_free_full (another_list, g_object_unref);
609 * Returns: a full copy of @list, use #g_list_free_full to free it
614 g_list_copy_deep (GList *list, GCopyFunc func, gpointer user_data)
616 GList *new_list = NULL;
622 new_list = _g_list_alloc ();
624 new_list->data = func (list->data, user_data);
626 new_list->data = list->data;
627 new_list->prev = NULL;
632 last->next = _g_list_alloc ();
633 last->next->prev = last;
636 last->data = func (list->data, user_data);
638 last->data = list->data;
652 * It simply switches the next and prev pointers of each element.
654 * Returns: the start of the reversed #GList
657 g_list_reverse (GList *list)
666 last->next = last->prev;
676 * @n: the position of the element, counting from 0
678 * Gets the element at the given position in a #GList.
680 * Returns: the element, or %NULL if the position is off
681 * the end of the #GList
684 g_list_nth (GList *list,
687 while ((n-- > 0) && list)
696 * @n: the position of the element, counting from 0
698 * Gets the element @n places before @list.
700 * Returns: the element, or %NULL if the position is
701 * off the end of the #GList
704 g_list_nth_prev (GList *list,
707 while ((n-- > 0) && list)
716 * @n: the position of the element
718 * Gets the data of the element at the given position.
720 * Returns: the element's data, or %NULL if the position
721 * is off the end of the #GList
724 g_list_nth_data (GList *list,
727 while ((n-- > 0) && list)
730 return list ? list->data : NULL;
736 * @data: the element data to find
738 * Finds the element in a #GList which
739 * contains the given data.
741 * Returns: the found #GList element,
742 * or %NULL if it is not found
745 g_list_find (GList *list,
750 if (list->data == data)
759 * g_list_find_custom:
761 * @data: user data passed to the function
762 * @func: the function to call for each element.
763 * It should return 0 when the desired element is found
765 * Finds an element in a #GList, using a supplied function to
766 * find the desired element. It iterates over the list, calling
767 * the given function which should return 0 when the desired
768 * element is found. The function takes two #gconstpointer arguments,
769 * the #GList element's data as the first argument and the
772 * Returns: the found #GList element, or %NULL if it is not found
775 g_list_find_custom (GList *list,
779 g_return_val_if_fail (func != NULL, list);
783 if (! func (list->data, data))
795 * @llink: an element in the #GList
797 * Gets the position of the given element
798 * in the #GList (starting from 0).
800 * Returns: the position of the element in the #GList,
801 * or -1 if the element is not found
804 g_list_position (GList *list,
824 * @data: the data to find
826 * Gets the position of the element containing
827 * the given data (starting from 0).
829 * Returns: the index of the element containing the data,
830 * or -1 if the data is not found
833 g_list_index (GList *list,
841 if (list->data == data)
854 * Gets the last element in a #GList.
856 * Returns: the last element in the #GList,
857 * or %NULL if the #GList has no elements
860 g_list_last (GList *list)
875 * Gets the first element in a #GList.
877 * Returns: the first element in the #GList,
878 * or %NULL if the #GList has no elements
881 g_list_first (GList *list)
896 * Gets the number of elements in a #GList.
899 * This function iterates over the whole list to
900 * count its elements.
903 * Returns: the number of elements in the #GList
906 g_list_length (GList *list)
923 * @func: the function to call with each element's data
924 * @user_data: user data to pass to the function
926 * Calls a function for each element of a #GList.
930 * @data: the element's data.
931 * @user_data: user data passed to g_list_foreach() or
934 * Specifies the type of functions passed to g_list_foreach() and
938 g_list_foreach (GList *list,
944 GList *next = list->next;
945 (*func) (list->data, user_data);
951 g_list_insert_sorted_real (GList *list,
956 GList *tmp_list = list;
960 g_return_val_if_fail (func != NULL, list);
964 new_list = _g_list_alloc0 ();
965 new_list->data = data;
969 cmp = ((GCompareDataFunc) func) (data, tmp_list->data, user_data);
971 while ((tmp_list->next) && (cmp > 0))
973 tmp_list = tmp_list->next;
975 cmp = ((GCompareDataFunc) func) (data, tmp_list->data, user_data);
978 new_list = _g_list_alloc0 ();
979 new_list->data = data;
981 if ((!tmp_list->next) && (cmp > 0))
983 tmp_list->next = new_list;
984 new_list->prev = tmp_list;
990 tmp_list->prev->next = new_list;
991 new_list->prev = tmp_list->prev;
993 new_list->next = tmp_list;
994 tmp_list->prev = new_list;
996 if (tmp_list == list)
1003 * g_list_insert_sorted:
1004 * @list: a pointer to a #GList
1005 * @data: the data for the new element
1006 * @func: the function to compare elements in the list. It should
1007 * return a number > 0 if the first parameter comes after the
1008 * second parameter in the sort order.
1010 * Inserts a new element into the list, using the given comparison
1011 * function to determine its position.
1013 * Returns: the new start of the #GList
1016 g_list_insert_sorted (GList *list,
1020 return g_list_insert_sorted_real (list, data, (GFunc) func, NULL);
1024 * g_list_insert_sorted_with_data:
1025 * @list: a pointer to a #GList
1026 * @data: the data for the new element
1027 * @func: the function to compare elements in the list.
1028 * It should return a number > 0 if the first parameter
1029 * comes after the second parameter in the sort order.
1030 * @user_data: user data to pass to comparison function.
1032 * Inserts a new element into the list, using the given comparison
1033 * function to determine its position.
1035 * Returns: the new start of the #GList
1040 g_list_insert_sorted_with_data (GList *list,
1042 GCompareDataFunc func,
1045 return g_list_insert_sorted_real (list, data, (GFunc) func, user_data);
1049 g_list_sort_merge (GList *l1,
1054 GList list, *l, *lprev;
1062 cmp = ((GCompareDataFunc) compare_func) (l1->data, l2->data, user_data);
1078 l->next = l1 ? l1 : l2;
1085 g_list_sort_real (GList *list,
1099 while ((l2 = l2->next) != NULL)
1101 if ((l2 = l2->next) == NULL)
1108 return g_list_sort_merge (g_list_sort_real (list, compare_func, user_data),
1109 g_list_sort_real (l2, compare_func, user_data),
1117 * @compare_func: the comparison function used to sort the #GList.
1118 * This function is passed the data from 2 elements of the #GList
1119 * and should return 0 if they are equal, a negative value if the
1120 * first element comes before the second, or a positive value if
1121 * the first element comes after the second.
1123 * Sorts a #GList using the given comparison function. The algorithm
1124 * used is a stable sort.
1126 * Returns: the start of the sorted #GList
1131 * @b: a value to compare with.
1133 * Specifies the type of a comparison function used to compare two
1134 * values. The function should return a negative integer if the first
1135 * value comes before the second, 0 if they are equal, or a positive
1136 * integer if the first value comes after the second.
1138 * Returns: negative value if @a < @b; zero if @a = @b; positive
1142 g_list_sort (GList *list,
1143 GCompareFunc compare_func)
1145 return g_list_sort_real (list, (GFunc) compare_func, NULL);
1150 * g_list_sort_with_data:
1152 * @compare_func: comparison function
1153 * @user_data: user data to pass to comparison function
1155 * Like g_list_sort(), but the comparison function accepts
1156 * a user data argument.
1158 * Returns: the new head of @list
1163 * @b: a value to compare with.
1164 * @user_data: user data to pass to comparison function.
1166 * Specifies the type of a comparison function used to compare two
1167 * values. The function should return a negative integer if the first
1168 * value comes before the second, 0 if they are equal, or a positive
1169 * integer if the first value comes after the second.
1171 * Returns: negative value if @a < @b; zero if @a = @b; positive
1175 g_list_sort_with_data (GList *list,
1176 GCompareDataFunc compare_func,
1179 return g_list_sort_real (list, (GFunc) compare_func, user_data);