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/.
35 #include "gtestutils.h"
38 * SECTION:linked_lists_double
39 * @title: Doubly-Linked Lists
40 * @short_description: linked lists containing integer values or
41 * pointers to data, with the ability to iterate
42 * over the list in both directions
44 * The #GList structure and its associated functions provide a standard
45 * doubly-linked list data structure.
47 * Each element in the list contains a piece of data, together with
48 * pointers which link to the previous and next elements in the list.
49 * Using these pointers it is possible to move through the list in both
50 * directions (unlike the <link
51 * linkend="glib-Singly-Linked-Lists">Singly-Linked Lists</link> which
52 * only allows movement through the list in the forward direction).
54 * The data contained in each element can be either integer values, by
55 * using one of the <link linkend="glib-Type-Conversion-Macros">Type
56 * Conversion Macros</link>, or simply pointers to any type of data.
58 * List elements are allocated from the <link
59 * linkend="glib-Memory-Slices">slice allocator</link>, which is more
60 * efficient than allocating elements individually.
62 * Note that most of the #GList functions expect to be passed a pointer
63 * to the first element in the list. The functions which insert
64 * elements return the new start of the list, which may have changed.
66 * There is no function to create a #GList. %NULL is considered to be
67 * the empty list so you simply set a #GList* to %NULL.
69 * To add elements, use g_list_append(), g_list_prepend(),
70 * g_list_insert() and g_list_insert_sorted().
72 * To remove elements, use g_list_remove().
74 * To find elements in the list use g_list_first(), g_list_last(),
75 * g_list_next(), g_list_previous(), g_list_nth(), g_list_nth_data(),
76 * g_list_find() and g_list_find_custom().
78 * To find the index of an element use g_list_position() and
81 * To call a function for each element in the list use g_list_foreach().
83 * To free the entire list, use g_list_free().
88 * @data: holds the element's data, which can be a pointer to any kind
89 * of data, or any integer value using the <link
90 * linkend="glib-Type-Conversion-Macros">Type Conversion
92 * @next: contains the link to the next element in the list.
93 * @prev: contains the link to the previous element in the list.
95 * The #GList struct is used for each element in a doubly-linked list.
100 * @list: an element in a #GList.
101 * @Returns: the previous element, or %NULL if there are no previous
104 * A convenience macro to get the previous element in a #GList.
109 * @list: an element in a #GList.
110 * @Returns: the next element, or %NULL if there are no more elements.
112 * A convenience macro to get the next element in a #GList.
115 #define _g_list_alloc() g_slice_new (GList)
116 #define _g_list_alloc0() g_slice_new0 (GList)
117 #define _g_list_free1(list) g_slice_free (GList, list)
121 * @Returns: a pointer to the newly-allocated #GList element.
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.
130 return _g_list_alloc0 ();
137 * Frees all of the memory used by a #GList.
138 * The freed elements are returned to the slice allocator.
141 * If list elements contain dynamically-allocated memory,
142 * you should either use g_list_free_full() or free them manually
147 g_list_free (GList *list)
149 g_slice_free_chain (GList, list, next);
154 * @list: a #GList element
156 * Frees one #GList element.
157 * It is usually used after g_list_remove_link().
162 * Another name for g_list_free_1().
165 g_list_free_1 (GList *list)
167 _g_list_free1 (list);
172 * @list: a pointer to a #GList
173 * @free_func: the function to be called to free each element's data
175 * Convenience method, which frees all the memory used by a #GList, and
176 * calls the specified destroy function on every element's data.
181 g_list_free_full (GList *list,
182 GDestroyNotify free_func)
184 g_list_foreach (list, (GFunc) free_func, NULL);
190 * @list: a pointer to a #GList
191 * @data: the data for the new element
193 * Adds a new element on to the end of the list.
196 * The return value is the new start of the list, which
197 * may have changed, so make sure you store the new value.
201 * Note that g_list_append() has to traverse the entire list
202 * to find the end, which is inefficient when adding multiple
203 * elements. A common idiom to avoid the inefficiency is to prepend
204 * the elements and reverse the list when all elements have been added.
208 * /* Notice that these are initialized to the empty list. */
209 * GList *list = NULL, *number_list = NULL;
211 * /* This is a list of strings. */
212 * list = g_list_append (list, "first");
213 * list = g_list_append (list, "second");
215 * /* This is a list of integers. */
216 * number_list = g_list_append (number_list, GINT_TO_POINTER (27));
217 * number_list = g_list_append (number_list, GINT_TO_POINTER (14));
220 * Returns: the new start of the #GList
223 g_list_append (GList *list,
229 new_list = _g_list_alloc ();
230 new_list->data = data;
231 new_list->next = NULL;
235 last = g_list_last (list);
236 /* g_assert (last != NULL); */
237 last->next = new_list;
238 new_list->prev = last;
244 new_list->prev = NULL;
251 * @list: a pointer to a #GList
252 * @data: the data for the new element
254 * Adds a new element on to the start of the list.
257 * The return value is the new start of the list, which
258 * may have changed, so make sure you store the new value.
262 * /* Notice that it is initialized to the empty list. */
263 * GList *list = NULL;
264 * list = g_list_prepend (list, "last");
265 * list = g_list_prepend (list, "first");
268 * Returns: the new start of the #GList
271 g_list_prepend (GList *list,
276 new_list = _g_list_alloc ();
277 new_list->data = data;
278 new_list->next = list;
282 new_list->prev = list->prev;
284 list->prev->next = new_list;
285 list->prev = new_list;
288 new_list->prev = NULL;
295 * @list: a pointer to a #GList
296 * @data: the data for the new element
297 * @position: the position to insert the element. If this is
298 * negative, or is larger than the number of elements in the
299 * list, the new element is added on to the end of the list.
301 * Inserts a new element into the list at the given position.
303 * Returns: the new start of the #GList
306 g_list_insert (GList *list,
314 return g_list_append (list, data);
315 else if (position == 0)
316 return g_list_prepend (list, data);
318 tmp_list = g_list_nth (list, position);
320 return g_list_append (list, data);
322 new_list = _g_list_alloc ();
323 new_list->data = data;
324 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;
330 if (tmp_list == list)
337 * g_list_insert_before:
338 * @list: a pointer to a #GList
339 * @sibling: the list element before which the new element
340 * is inserted or %NULL to insert at the end of the list
341 * @data: the data for the new element
343 * Inserts a new element into the list before the given position.
345 * Returns: the new start of the #GList
348 g_list_insert_before (GList *list,
354 list = g_list_alloc ();
356 g_return_val_if_fail (sibling == NULL, list);
363 node = _g_list_alloc ();
365 node->prev = sibling->prev;
366 node->next = sibling;
367 sibling->prev = node;
370 node->prev->next = node;
375 g_return_val_if_fail (sibling == list, node);
387 last->next = _g_list_alloc ();
388 last->next->data = data;
389 last->next->prev = last;
390 last->next->next = NULL;
399 * @list2: the #GList to add to the end of the first #GList
401 * Adds the second #GList onto the end of the first #GList.
402 * Note that the elements of the second #GList are not copied.
403 * They are used directly.
405 * Returns: the start of the new #GList
408 g_list_concat (GList *list1, GList *list2)
414 tmp_list = g_list_last (list1);
416 tmp_list->next = list2;
419 list2->prev = tmp_list;
428 * @data: the data of the element to remove
430 * Removes an element from a #GList.
431 * If two elements contain the same data, only the first is removed.
432 * If none of the elements contain the data, the #GList is unchanged.
434 * Returns: the new start of the #GList
437 g_list_remove (GList *list,
445 if (tmp->data != data)
450 tmp->prev->next = tmp->next;
452 tmp->next->prev = tmp->prev;
468 * @data: data to remove
470 * Removes all list nodes with data equal to @data.
471 * Returns the new head of the list. Contrast with
472 * g_list_remove() which removes only the first node
473 * matching the given data.
475 * Returns: new head of @list
478 g_list_remove_all (GList *list,
485 if (tmp->data != data)
489 GList *next = tmp->next;
492 tmp->prev->next = next;
496 next->prev = tmp->prev;
506 _g_list_remove_link (GList *list,
512 link->prev->next = link->next;
514 link->next->prev = link->prev;
527 * g_list_remove_link:
529 * @llink: an element in the #GList
531 * Removes an element from a #GList, without freeing the element.
532 * The removed element's prev and next links are set to %NULL, so
533 * that it becomes a self-contained list with one element.
535 * Returns: the new start of the #GList, without the element
538 g_list_remove_link (GList *list,
541 return _g_list_remove_link (list, llink);
545 * g_list_delete_link:
547 * @link_: node to delete from @list
549 * Removes the node link_ from the list and frees it.
550 * Compare this to g_list_remove_link() which removes the node
551 * without freeing it.
553 * Returns: the new head of @list
556 g_list_delete_link (GList *list,
559 list = _g_list_remove_link (list, link_);
560 _g_list_free1 (link_);
572 * Note that this is a "shallow" copy. If the list elements
573 * consist of pointers to data, the pointers are copied but
574 * the actual data is not.
577 * Returns: a copy of @list
580 g_list_copy (GList *list)
582 GList *new_list = NULL;
588 new_list = _g_list_alloc ();
589 new_list->data = list->data;
590 new_list->prev = NULL;
595 last->next = _g_list_alloc ();
596 last->next->prev = last;
598 last->data = list->data;
612 * It simply switches the next and prev pointers of each element.
614 * Returns: the start of the reversed #GList
617 g_list_reverse (GList *list)
626 last->next = last->prev;
636 * @n: the position of the element, counting from 0
638 * Gets the element at the given position in a #GList.
640 * Returns: the element, or %NULL if the position is off
641 * the end of the #GList
644 g_list_nth (GList *list,
647 while ((n-- > 0) && list)
656 * @n: the position of the element, counting from 0
658 * Gets the element @n places before @list.
660 * Returns: the element, or %NULL if the position is
661 * off the end of the #GList
664 g_list_nth_prev (GList *list,
667 while ((n-- > 0) && list)
676 * @n: the position of the element
678 * Gets the data of the element at the given position.
680 * Returns: the element's data, or %NULL if the position
681 * is off the end of the #GList
684 g_list_nth_data (GList *list,
687 while ((n-- > 0) && list)
690 return list ? list->data : NULL;
696 * @data: the element data to find
698 * Finds the element in a #GList which
699 * contains the given data.
701 * Returns: the found #GList element,
702 * or %NULL if it is not found
705 g_list_find (GList *list,
710 if (list->data == data)
719 * g_list_find_custom:
721 * @data: user data passed to the function
722 * @func: the function to call for each element.
723 * It should return 0 when the desired element is found
725 * Finds an element in a #GList, using a supplied function to
726 * find the desired element. It iterates over the list, calling
727 * the given function which should return 0 when the desired
728 * element is found. The function takes two #gconstpointer arguments,
729 * the #GList element's data as the first argument and the
732 * Returns: the found #GList element, or %NULL if it is not found
735 g_list_find_custom (GList *list,
739 g_return_val_if_fail (func != NULL, list);
743 if (! func (list->data, data))
755 * @llink: an element in the #GList
757 * Gets the position of the given element
758 * in the #GList (starting from 0).
760 * Returns: the position of the element in the #GList,
761 * or -1 if the element is not found
764 g_list_position (GList *list,
784 * @data: the data to find
786 * Gets the position of the element containing
787 * the given data (starting from 0).
789 * Returns: the index of the element containing the data,
790 * or -1 if the data is not found
793 g_list_index (GList *list,
801 if (list->data == data)
814 * Gets the last element in a #GList.
816 * Returns: the last element in the #GList,
817 * or %NULL if the #GList has no elements
820 g_list_last (GList *list)
835 * Gets the first element in a #GList.
837 * Returns: the first element in the #GList,
838 * or %NULL if the #GList has no elements
841 g_list_first (GList *list)
856 * Gets the number of elements in a #GList.
859 * This function iterates over the whole list to
860 * count its elements.
863 * Returns: the number of elements in the #GList
866 g_list_length (GList *list)
883 * @func: the function to call with each element's data
884 * @user_data: user data to pass to the function
886 * Calls a function for each element of a #GList.
890 * @data: the element's data.
891 * @user_data: user data passed to g_list_foreach() or
894 * Specifies the type of functions passed to g_list_foreach() and
898 g_list_foreach (GList *list,
904 GList *next = list->next;
905 (*func) (list->data, user_data);
911 g_list_insert_sorted_real (GList *list,
916 GList *tmp_list = list;
920 g_return_val_if_fail (func != NULL, list);
924 new_list = _g_list_alloc0 ();
925 new_list->data = data;
929 cmp = ((GCompareDataFunc) func) (data, tmp_list->data, user_data);
931 while ((tmp_list->next) && (cmp > 0))
933 tmp_list = tmp_list->next;
935 cmp = ((GCompareDataFunc) func) (data, tmp_list->data, user_data);
938 new_list = _g_list_alloc0 ();
939 new_list->data = data;
941 if ((!tmp_list->next) && (cmp > 0))
943 tmp_list->next = new_list;
944 new_list->prev = tmp_list;
950 tmp_list->prev->next = new_list;
951 new_list->prev = tmp_list->prev;
953 new_list->next = tmp_list;
954 tmp_list->prev = new_list;
956 if (tmp_list == list)
963 * g_list_insert_sorted:
964 * @list: a pointer to a #GList
965 * @data: the data for the new element
966 * @func: the function to compare elements in the list. It should
967 * return a number > 0 if the first parameter comes after the
968 * second parameter in the sort order.
970 * Inserts a new element into the list, using the given comparison
971 * function to determine its position.
973 * Returns: the new start of the #GList
976 g_list_insert_sorted (GList *list,
980 return g_list_insert_sorted_real (list, data, (GFunc) func, NULL);
984 * g_list_insert_sorted_with_data:
985 * @list: a pointer to a #GList
986 * @data: the data for the new element
987 * @func: the function to compare elements in the list.
988 * It should return a number > 0 if the first parameter
989 * comes after the second parameter in the sort order.
990 * @user_data: user data to pass to comparison function.
992 * Inserts a new element into the list, using the given comparison
993 * function to determine its position.
995 * Returns: the new start of the #GList
1000 g_list_insert_sorted_with_data (GList *list,
1002 GCompareDataFunc func,
1005 return g_list_insert_sorted_real (list, data, (GFunc) func, user_data);
1009 g_list_sort_merge (GList *l1,
1014 GList list, *l, *lprev;
1022 cmp = ((GCompareDataFunc) compare_func) (l1->data, l2->data, user_data);
1038 l->next = l1 ? l1 : l2;
1045 g_list_sort_real (GList *list,
1059 while ((l2 = l2->next) != NULL)
1061 if ((l2 = l2->next) == NULL)
1068 return g_list_sort_merge (g_list_sort_real (list, compare_func, user_data),
1069 g_list_sort_real (l2, compare_func, user_data),
1077 * @compare_func: the comparison function used to sort the #GList.
1078 * This function is passed the data from 2 elements of the #GList
1079 * and should return 0 if they are equal, a negative value if the
1080 * first element comes before the second, or a positive value if
1081 * the first element comes after the second.
1083 * Sorts a #GList using the given comparison function.
1085 * Returns: the start of the sorted #GList
1090 * @b: a value to compare with.
1091 * @Returns: negative value if @a < @b; zero if @a = @b; positive
1094 * Specifies the type of a comparison function used to compare two
1095 * values. The function should return a negative integer if the first
1096 * value comes before the second, 0 if they are equal, or a positive
1097 * integer if the first value comes after the second.
1100 g_list_sort (GList *list,
1101 GCompareFunc compare_func)
1103 return g_list_sort_real (list, (GFunc) compare_func, NULL);
1108 * g_list_sort_with_data:
1110 * @compare_func: comparison function
1111 * @user_data: user data to pass to comparison function
1113 * Like g_list_sort(), but the comparison function accepts
1114 * a user data argument.
1116 * Returns: the new head of @list
1121 * @b: a value to compare with.
1122 * @user_data: user data to pass to comparison function.
1123 * @Returns: negative value if @a < @b; zero if @a = @b; positive
1126 * Specifies the type of a comparison function used to compare two
1127 * values. The function should return a negative integer if the first
1128 * value comes before the second, 0 if they are equal, or a positive
1129 * integer if the first value comes after the second.
1132 g_list_sort_with_data (GList *list,
1133 GCompareDataFunc compare_func,
1136 return g_list_sort_real (list, (GFunc) compare_func, user_data);