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 containing integer values or
42 * pointers to data, with the ability to iterate
43 * over the list in both directions
45 * The #GList structure and its associated functions provide a standard
46 * doubly-linked list data structure.
48 * Each element in the list contains a piece of data, together with
49 * pointers which link to the previous and next elements in the list.
50 * Using these pointers it is possible to move through the list in both
51 * directions (unlike the <link
52 * linkend="glib-Singly-Linked-Lists">Singly-Linked Lists</link> which
53 * only allows movement through the list in the forward direction).
55 * The data contained in each element can be either integer values, by
56 * using one of the <link linkend="glib-Type-Conversion-Macros">Type
57 * Conversion Macros</link>, or simply pointers to any type of data.
59 * List elements are allocated from the <link
60 * linkend="glib-Memory-Slices">slice allocator</link>, which is more
61 * efficient than allocating elements individually.
63 * Note that most of the #GList functions expect to be passed a pointer
64 * to the first element in the list. The functions which insert
65 * elements return the new start of the list, which may have changed.
67 * There is no function to create a #GList. %NULL is considered to be
68 * the empty list so you simply set a #GList* to %NULL.
70 * To add elements, use g_list_append(), g_list_prepend(),
71 * g_list_insert() and g_list_insert_sorted().
73 * To remove elements, use g_list_remove().
75 * To find elements in the list use g_list_first(), g_list_last(),
76 * g_list_next(), g_list_previous(), g_list_nth(), g_list_nth_data(),
77 * g_list_find() and g_list_find_custom().
79 * To find the index of an element use g_list_position() and
82 * To call a function for each element in the list use g_list_foreach().
84 * To free the entire list, use g_list_free().
89 * @data: holds the element's data, which can be a pointer to any kind
90 * of data, or any integer value using the <link
91 * linkend="glib-Type-Conversion-Macros">Type Conversion
93 * @next: contains the link to the next element in the list.
94 * @prev: contains the link to the previous element in the list.
96 * The #GList struct is used for each element in a doubly-linked list.
101 * @list: an element in a #GList.
102 * @Returns: the previous element, or %NULL if there are no previous
105 * A convenience macro to get the previous element in a #GList.
110 * @list: an element in a #GList.
111 * @Returns: the next element, or %NULL if there are no more elements.
113 * A convenience macro to get the next element in a #GList.
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)
122 * @Returns: a pointer to the newly-allocated #GList element.
124 * Allocates space for one #GList element. It is called by
125 * g_list_append(), g_list_prepend(), g_list_insert() and
126 * g_list_insert_sorted() and so is rarely used on its own.
131 return _g_list_alloc0 ();
138 * Frees all of the memory used by a #GList.
139 * The freed elements are returned to the slice allocator.
142 * If list elements contain dynamically-allocated memory,
143 * you should either use g_list_free_full() or free them manually
148 g_list_free (GList *list)
150 g_slice_free_chain (GList, list, next);
155 * @list: a #GList element
157 * Frees one #GList element.
158 * It is usually used after g_list_remove_link().
163 * Another name for g_list_free_1().
166 g_list_free_1 (GList *list)
168 _g_list_free1 (list);
173 * @list: a pointer to a #GList
174 * @free_func: the function to be called to free each element's data
176 * Convenience method, which frees all the memory used by a #GList, and
177 * calls the specified destroy function on every element's data.
182 g_list_free_full (GList *list,
183 GDestroyNotify free_func)
185 g_list_foreach (list, (GFunc) free_func, NULL);
191 * @list: a pointer to a #GList
192 * @data: the data for the new element
194 * Adds a new element on to the end of the list.
197 * The return value is the new start of the list, which
198 * may have changed, so make sure you store the new value.
202 * Note that g_list_append() has to traverse the entire list
203 * to find the end, which is inefficient when adding multiple
204 * elements. A common idiom to avoid the inefficiency is to prepend
205 * the elements and reverse the list when all elements have been added.
209 * /* Notice that these are initialized to the empty list. */
210 * GList *list = NULL, *number_list = NULL;
212 * /* This is a list of strings. */
213 * list = g_list_append (list, "first");
214 * list = g_list_append (list, "second");
216 * /* This is a list of integers. */
217 * number_list = g_list_append (number_list, GINT_TO_POINTER (27));
218 * number_list = g_list_append (number_list, GINT_TO_POINTER (14));
221 * Returns: the new start of the #GList
224 g_list_append (GList *list,
230 new_list = _g_list_alloc ();
231 new_list->data = data;
232 new_list->next = NULL;
236 last = g_list_last (list);
237 /* g_assert (last != NULL); */
238 last->next = new_list;
239 new_list->prev = last;
245 new_list->prev = NULL;
252 * @list: a pointer to a #GList
253 * @data: the data for the new element
255 * Adds a new element on to the start of the list.
258 * The return value is the new start of the list, which
259 * may have changed, so make sure you store the new value.
263 * /* Notice that it is initialized to the empty list. */
264 * GList *list = NULL;
265 * list = g_list_prepend (list, "last");
266 * list = g_list_prepend (list, "first");
269 * Returns: the new start of the #GList
272 g_list_prepend (GList *list,
277 new_list = _g_list_alloc ();
278 new_list->data = data;
279 new_list->next = list;
283 new_list->prev = list->prev;
285 list->prev->next = new_list;
286 list->prev = new_list;
289 new_list->prev = NULL;
296 * @list: a pointer to a #GList
297 * @data: the data for the new element
298 * @position: the position to insert the element. If this is
299 * negative, or is larger than the number of elements in the
300 * list, the new element is added on to the end of the list.
302 * Inserts a new element into the list at the given position.
304 * Returns: the new start of the #GList
307 g_list_insert (GList *list,
315 return g_list_append (list, data);
316 else if (position == 0)
317 return g_list_prepend (list, data);
319 tmp_list = g_list_nth (list, position);
321 return g_list_append (list, data);
323 new_list = _g_list_alloc ();
324 new_list->data = data;
325 new_list->prev = tmp_list->prev;
326 tmp_list->prev->next = new_list;
327 new_list->next = tmp_list;
328 tmp_list->prev = new_list;
334 * g_list_insert_before:
335 * @list: a pointer to a #GList
336 * @sibling: the list element before which the new element
337 * is inserted or %NULL to insert at the end of the list
338 * @data: the data for the new element
340 * Inserts a new element into the list before the given position.
342 * Returns: the new start of the #GList
345 g_list_insert_before (GList *list,
351 list = g_list_alloc ();
353 g_return_val_if_fail (sibling == NULL, list);
360 node = _g_list_alloc ();
362 node->prev = sibling->prev;
363 node->next = sibling;
364 sibling->prev = node;
367 node->prev->next = node;
372 g_return_val_if_fail (sibling == list, node);
384 last->next = _g_list_alloc ();
385 last->next->data = data;
386 last->next->prev = last;
387 last->next->next = NULL;
396 * @list2: the #GList to add to the end of the first #GList
398 * Adds the second #GList onto the end of the first #GList.
399 * Note that the elements of the second #GList are not copied.
400 * They are used directly.
402 * Returns: the start of the new #GList
405 g_list_concat (GList *list1, GList *list2)
411 tmp_list = g_list_last (list1);
413 tmp_list->next = list2;
416 list2->prev = tmp_list;
425 * @data: the data of the element to remove
427 * Removes an element from a #GList.
428 * If two elements contain the same data, only the first is removed.
429 * If none of the elements contain the data, the #GList is unchanged.
431 * Returns: the new start of the #GList
434 g_list_remove (GList *list,
442 if (tmp->data != data)
447 tmp->prev->next = tmp->next;
449 tmp->next->prev = tmp->prev;
465 * @data: data to remove
467 * Removes all list nodes with data equal to @data.
468 * Returns the new head of the list. Contrast with
469 * g_list_remove() which removes only the first node
470 * matching the given data.
472 * Returns: new head of @list
475 g_list_remove_all (GList *list,
482 if (tmp->data != data)
486 GList *next = tmp->next;
489 tmp->prev->next = next;
493 next->prev = tmp->prev;
503 _g_list_remove_link (GList *list,
509 link->prev->next = link->next;
511 link->next->prev = link->prev;
524 * g_list_remove_link:
526 * @llink: an element in the #GList
528 * Removes an element from a #GList, without freeing the element.
529 * The removed element's prev and next links are set to %NULL, so
530 * that it becomes a self-contained list with one element.
532 * Returns: the new start of the #GList, without the element
535 g_list_remove_link (GList *list,
538 return _g_list_remove_link (list, llink);
542 * g_list_delete_link:
544 * @link_: node to delete from @list
546 * Removes the node link_ from the list and frees it.
547 * Compare this to g_list_remove_link() which removes the node
548 * without freeing it.
550 * Returns: the new head of @list
553 g_list_delete_link (GList *list,
556 list = _g_list_remove_link (list, link_);
557 _g_list_free1 (link_);
569 * Note that this is a "shallow" copy. If the list elements
570 * consist of pointers to data, the pointers are copied but
571 * the actual data is not.
574 * Returns: a copy of @list
577 g_list_copy (GList *list)
579 GList *new_list = NULL;
585 new_list = _g_list_alloc ();
586 new_list->data = list->data;
587 new_list->prev = NULL;
592 last->next = _g_list_alloc ();
593 last->next->prev = last;
595 last->data = list->data;
609 * It simply switches the next and prev pointers of each element.
611 * Returns: the start of the reversed #GList
614 g_list_reverse (GList *list)
623 last->next = last->prev;
633 * @n: the position of the element, counting from 0
635 * Gets the element at the given position in a #GList.
637 * Returns: the element, or %NULL if the position is off
638 * the end of the #GList
641 g_list_nth (GList *list,
644 while ((n-- > 0) && list)
653 * @n: the position of the element, counting from 0
655 * Gets the element @n places before @list.
657 * Returns: the element, or %NULL if the position is
658 * off the end of the #GList
661 g_list_nth_prev (GList *list,
664 while ((n-- > 0) && list)
673 * @n: the position of the element
675 * Gets the data of the element at the given position.
677 * Returns: the element's data, or %NULL if the position
678 * is off the end of the #GList
681 g_list_nth_data (GList *list,
684 while ((n-- > 0) && list)
687 return list ? list->data : NULL;
693 * @data: the element data to find
695 * Finds the element in a #GList which
696 * contains the given data.
698 * Returns: the found #GList element,
699 * or %NULL if it is not found
702 g_list_find (GList *list,
707 if (list->data == data)
716 * g_list_find_custom:
718 * @data: user data passed to the function
719 * @func: the function to call for each element.
720 * It should return 0 when the desired element is found
722 * Finds an element in a #GList, using a supplied function to
723 * find the desired element. It iterates over the list, calling
724 * the given function which should return 0 when the desired
725 * element is found. The function takes two #gconstpointer arguments,
726 * the #GList element's data as the first argument and the
729 * Returns: the found #GList element, or %NULL if it is not found
732 g_list_find_custom (GList *list,
736 g_return_val_if_fail (func != NULL, list);
740 if (! func (list->data, data))
752 * @llink: an element in the #GList
754 * Gets the position of the given element
755 * in the #GList (starting from 0).
757 * Returns: the position of the element in the #GList,
758 * or -1 if the element is not found
761 g_list_position (GList *list,
781 * @data: the data to find
783 * Gets the position of the element containing
784 * the given data (starting from 0).
786 * Returns: the index of the element containing the data,
787 * or -1 if the data is not found
790 g_list_index (GList *list,
798 if (list->data == data)
811 * Gets the last element in a #GList.
813 * Returns: the last element in the #GList,
814 * or %NULL if the #GList has no elements
817 g_list_last (GList *list)
832 * Gets the first element in a #GList.
834 * Returns: the first element in the #GList,
835 * or %NULL if the #GList has no elements
838 g_list_first (GList *list)
853 * Gets the number of elements in a #GList.
856 * This function iterates over the whole list to
857 * count its elements.
860 * Returns: the number of elements in the #GList
863 g_list_length (GList *list)
880 * @func: the function to call with each element's data
881 * @user_data: user data to pass to the function
883 * Calls a function for each element of a #GList.
887 * @data: the element's data.
888 * @user_data: user data passed to g_list_foreach() or
891 * Specifies the type of functions passed to g_list_foreach() and
895 g_list_foreach (GList *list,
901 GList *next = list->next;
902 (*func) (list->data, user_data);
908 g_list_insert_sorted_real (GList *list,
913 GList *tmp_list = list;
917 g_return_val_if_fail (func != NULL, list);
921 new_list = _g_list_alloc0 ();
922 new_list->data = data;
926 cmp = ((GCompareDataFunc) func) (data, tmp_list->data, user_data);
928 while ((tmp_list->next) && (cmp > 0))
930 tmp_list = tmp_list->next;
932 cmp = ((GCompareDataFunc) func) (data, tmp_list->data, user_data);
935 new_list = _g_list_alloc0 ();
936 new_list->data = data;
938 if ((!tmp_list->next) && (cmp > 0))
940 tmp_list->next = new_list;
941 new_list->prev = tmp_list;
947 tmp_list->prev->next = new_list;
948 new_list->prev = tmp_list->prev;
950 new_list->next = tmp_list;
951 tmp_list->prev = new_list;
953 if (tmp_list == list)
960 * g_list_insert_sorted:
961 * @list: a pointer to a #GList
962 * @data: the data for the new element
963 * @func: the function to compare elements in the list. It should
964 * return a number > 0 if the first parameter comes after the
965 * second parameter in the sort order.
967 * Inserts a new element into the list, using the given comparison
968 * function to determine its position.
970 * Returns: the new start of the #GList
973 g_list_insert_sorted (GList *list,
977 return g_list_insert_sorted_real (list, data, (GFunc) func, NULL);
981 * g_list_insert_sorted_with_data:
982 * @list: a pointer to a #GList
983 * @data: the data for the new element
984 * @func: the function to compare elements in the list.
985 * It should return a number > 0 if the first parameter
986 * comes after the second parameter in the sort order.
987 * @user_data: user data to pass to comparison function.
989 * Inserts a new element into the list, using the given comparison
990 * function to determine its position.
992 * Returns: the new start of the #GList
997 g_list_insert_sorted_with_data (GList *list,
999 GCompareDataFunc func,
1002 return g_list_insert_sorted_real (list, data, (GFunc) func, user_data);
1006 g_list_sort_merge (GList *l1,
1011 GList list, *l, *lprev;
1019 cmp = ((GCompareDataFunc) compare_func) (l1->data, l2->data, user_data);
1035 l->next = l1 ? l1 : l2;
1042 g_list_sort_real (GList *list,
1056 while ((l2 = l2->next) != NULL)
1058 if ((l2 = l2->next) == NULL)
1065 return g_list_sort_merge (g_list_sort_real (list, compare_func, user_data),
1066 g_list_sort_real (l2, compare_func, user_data),
1074 * @compare_func: the comparison function used to sort the #GList.
1075 * This function is passed the data from 2 elements of the #GList
1076 * and should return 0 if they are equal, a negative value if the
1077 * first element comes before the second, or a positive value if
1078 * the first element comes after the second.
1080 * Sorts a #GList using the given comparison function.
1082 * Returns: the start of the sorted #GList
1087 * @b: a value to compare with.
1088 * @Returns: negative value if @a < @b; zero if @a = @b; positive
1091 * Specifies the type of a comparison function used to compare two
1092 * values. The function should return a negative integer if the first
1093 * value comes before the second, 0 if they are equal, or a positive
1094 * integer if the first value comes after the second.
1097 g_list_sort (GList *list,
1098 GCompareFunc compare_func)
1100 return g_list_sort_real (list, (GFunc) compare_func, NULL);
1105 * g_list_sort_with_data:
1107 * @compare_func: comparison function
1108 * @user_data: user data to pass to comparison function
1110 * Like g_list_sort(), but the comparison function accepts
1111 * a user data argument.
1113 * Returns: the new head of @list
1118 * @b: a value to compare with.
1119 * @user_data: user data to pass to comparison function.
1120 * @Returns: negative value if @a < @b; zero if @a = @b; positive
1123 * Specifies the type of a comparison function used to compare two
1124 * values. The function should return a negative integer if the first
1125 * value comes before the second, 0 if they are equal, or a positive
1126 * integer if the first value comes after the second.
1129 g_list_sort_with_data (GList *list,
1130 GCompareDataFunc compare_func,
1133 return g_list_sort_real (list, (GFunc) compare_func, user_data);