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.
118 * g_list_push_allocator:
119 * @allocator: the #GAllocator to use when allocating #GList elements.
121 * Sets the allocator to use to allocate #GList elements. Use
122 * g_list_pop_allocator() to restore the previous allocator.
124 * Note that this function is not available if GLib has been compiled
125 * with <option>--disable-mem-pools</option>
127 * Deprecated:2.10: It does nothing, since #GList has been converted
128 * to the <link linkend="glib-Memory-Slices">slice
131 void g_list_push_allocator (gpointer dummy) { /* present for binary compat only */ }
134 * g_list_pop_allocator:
136 * Restores the previous #GAllocator, used when allocating #GList
139 * Note that this function is not available if GLib has been compiled
140 * with <option>--disable-mem-pools</option>
142 * Deprecated:2.10: It does nothing, since #GList has been converted
143 * to the <link linkend="glib-Memory-Slices">slice
146 void g_list_pop_allocator (void) { /* present for binary compat only */ }
148 #define _g_list_alloc() g_slice_new (GList)
149 #define _g_list_alloc0() g_slice_new0 (GList)
150 #define _g_list_free1(list) g_slice_free (GList, list)
154 * @Returns: a pointer to the newly-allocated #GList element.
156 * Allocates space for one #GList element. It is called by
157 * g_list_append(), g_list_prepend(), g_list_insert() and
158 * g_list_insert_sorted() and so is rarely used on its own.
163 return _g_list_alloc0 ();
170 * Frees all of the memory used by a #GList.
171 * The freed elements are returned to the slice allocator.
174 * If list elements contain dynamically-allocated memory,
175 * you should either use g_list_free_full() or free them manually
180 g_list_free (GList *list)
182 g_slice_free_chain (GList, list, next);
187 * @list: a #GList element
189 * Frees one #GList element.
190 * It is usually used after g_list_remove_link().
195 * Another name for g_list_free_1().
198 g_list_free_1 (GList *list)
200 _g_list_free1 (list);
205 * @list: a pointer to a #GList
206 * @free_func: the function to be called to free each element's data
208 * Convenience method, which frees all the memory used by a #GList, and
209 * calls the specified destroy function on every element's data.
214 g_list_free_full (GList *list,
215 GDestroyNotify free_func)
219 GList *next = list->next;
220 (*free_func) (list->data);
221 _g_list_free1 (list);
228 * @list: a pointer to a #GList
229 * @data: the data for the new element
231 * Adds a new element on to the end of the list.
234 * The return value is the new start of the list, which
235 * may have changed, so make sure you store the new value.
239 * Note that g_list_append() has to traverse the entire list
240 * to find the end, which is inefficient when adding multiple
241 * elements. A common idiom to avoid the inefficiency is to prepend
242 * the elements and reverse the list when all elements have been added.
246 * /* Notice that these are initialized to the empty list. */
247 * GList *list = NULL, *number_list = NULL;
249 * /* This is a list of strings. */
250 * list = g_list_append (list, "first");
251 * list = g_list_append (list, "second");
253 * /* This is a list of integers. */
254 * number_list = g_list_append (number_list, GINT_TO_POINTER (27));
255 * number_list = g_list_append (number_list, GINT_TO_POINTER (14));
258 * Returns: the new start of the #GList
261 g_list_append (GList *list,
267 new_list = _g_list_alloc ();
268 new_list->data = data;
269 new_list->next = NULL;
273 last = g_list_last (list);
274 /* g_assert (last != NULL); */
275 last->next = new_list;
276 new_list->prev = last;
282 new_list->prev = NULL;
289 * @list: a pointer to a #GList
290 * @data: the data for the new element
292 * Adds a new element on to the start of the list.
295 * The return value is the new start of the list, which
296 * may have changed, so make sure you store the new value.
300 * /* Notice that it is initialized to the empty list. */
301 * GList *list = NULL;
302 * list = g_list_prepend (list, "last");
303 * list = g_list_prepend (list, "first");
306 * Returns: the new start of the #GList
309 g_list_prepend (GList *list,
314 new_list = _g_list_alloc ();
315 new_list->data = data;
316 new_list->next = list;
320 new_list->prev = list->prev;
322 list->prev->next = new_list;
323 list->prev = new_list;
326 new_list->prev = NULL;
333 * @list: a pointer to a #GList
334 * @data: the data for the new element
335 * @position: the position to insert the element. If this is
336 * negative, or is larger than the number of elements in the
337 * list, the new element is added on to the end of the list.
339 * Inserts a new element into the list at the given position.
341 * Returns: the new start of the #GList
344 g_list_insert (GList *list,
352 return g_list_append (list, data);
353 else if (position == 0)
354 return g_list_prepend (list, data);
356 tmp_list = g_list_nth (list, position);
358 return g_list_append (list, data);
360 new_list = _g_list_alloc ();
361 new_list->data = data;
362 new_list->prev = tmp_list->prev;
364 tmp_list->prev->next = new_list;
365 new_list->next = tmp_list;
366 tmp_list->prev = new_list;
368 if (tmp_list == list)
375 * g_list_insert_before:
376 * @list: a pointer to a #GList
377 * @sibling: the list element before which the new element
378 * is inserted or %NULL to insert at the end of the list
379 * @data: the data for the new element
381 * Inserts a new element into the list before the given position.
383 * Returns: the new start of the #GList
386 g_list_insert_before (GList *list,
392 list = g_list_alloc ();
394 g_return_val_if_fail (sibling == NULL, list);
401 node = _g_list_alloc ();
403 node->prev = sibling->prev;
404 node->next = sibling;
405 sibling->prev = node;
408 node->prev->next = node;
413 g_return_val_if_fail (sibling == list, node);
425 last->next = _g_list_alloc ();
426 last->next->data = data;
427 last->next->prev = last;
428 last->next->next = NULL;
437 * @list2: the #GList to add to the end of the first #GList
439 * Adds the second #GList onto the end of the first #GList.
440 * Note that the elements of the second #GList are not copied.
441 * They are used directly.
443 * Returns: the start of the new #GList
446 g_list_concat (GList *list1, GList *list2)
452 tmp_list = g_list_last (list1);
454 tmp_list->next = list2;
457 list2->prev = tmp_list;
466 * @data: the data of the element to remove
468 * Removes an element from a #GList.
469 * If two elements contain the same data, only the first is removed.
470 * If none of the elements contain the data, the #GList is unchanged.
472 * Returns: the new start of the #GList
475 g_list_remove (GList *list,
483 if (tmp->data != data)
488 tmp->prev->next = tmp->next;
490 tmp->next->prev = tmp->prev;
506 * @data: data to remove
508 * Removes all list nodes with data equal to @data.
509 * Returns the new head of the list. Contrast with
510 * g_list_remove() which removes only the first node
511 * matching the given data.
513 * Returns: new head of @list
516 g_list_remove_all (GList *list,
523 if (tmp->data != data)
527 GList *next = tmp->next;
530 tmp->prev->next = next;
534 next->prev = tmp->prev;
544 _g_list_remove_link (GList *list,
550 link->prev->next = link->next;
552 link->next->prev = link->prev;
565 * g_list_remove_link:
567 * @llink: an element in the #GList
569 * Removes an element from a #GList, without freeing the element.
570 * The removed element's prev and next links are set to %NULL, so
571 * that it becomes a self-contained list with one element.
573 * Returns: the new start of the #GList, without the element
576 g_list_remove_link (GList *list,
579 return _g_list_remove_link (list, llink);
583 * g_list_delete_link:
585 * @link_: node to delete from @list
587 * Removes the node link_ from the list and frees it.
588 * Compare this to g_list_remove_link() which removes the node
589 * without freeing it.
591 * Returns: the new head of @list
594 g_list_delete_link (GList *list,
597 list = _g_list_remove_link (list, link_);
598 _g_list_free1 (link_);
610 * Note that this is a "shallow" copy. If the list elements
611 * consist of pointers to data, the pointers are copied but
612 * the actual data is not.
615 * Returns: a copy of @list
618 g_list_copy (GList *list)
620 GList *new_list = NULL;
626 new_list = _g_list_alloc ();
627 new_list->data = list->data;
628 new_list->prev = NULL;
633 last->next = _g_list_alloc ();
634 last->next->prev = last;
636 last->data = list->data;
650 * It simply switches the next and prev pointers of each element.
652 * Returns: the start of the reversed #GList
655 g_list_reverse (GList *list)
664 last->next = last->prev;
674 * @n: the position of the element, counting from 0
676 * Gets the element at the given position in a #GList.
678 * Returns: the element, or %NULL if the position is off
679 * the end of the #GList
682 g_list_nth (GList *list,
685 while ((n-- > 0) && list)
694 * @n: the position of the element, counting from 0
696 * Gets the element @n places before @list.
698 * Returns: the element, or %NULL if the position is
699 * off the end of the #GList
702 g_list_nth_prev (GList *list,
705 while ((n-- > 0) && list)
714 * @n: the position of the element
716 * Gets the data of the element at the given position.
718 * Returns: the element's data, or %NULL if the position
719 * is off the end of the #GList
722 g_list_nth_data (GList *list,
725 while ((n-- > 0) && list)
728 return list ? list->data : NULL;
734 * @data: the element data to find
736 * Finds the element in a #GList which
737 * contains the given data.
739 * Returns: the found #GList element,
740 * or %NULL if it is not found
743 g_list_find (GList *list,
748 if (list->data == data)
757 * g_list_find_custom:
759 * @data: user data passed to the function
760 * @func: the function to call for each element.
761 * It should return 0 when the desired element is found
763 * Finds an element in a #GList, using a supplied function to
764 * find the desired element. It iterates over the list, calling
765 * the given function which should return 0 when the desired
766 * element is found. The function takes two #gconstpointer arguments,
767 * the #GList element's data as the first argument and the
770 * Returns: the found #GList element, or %NULL if it is not found
773 g_list_find_custom (GList *list,
777 g_return_val_if_fail (func != NULL, list);
781 if (! func (list->data, data))
793 * @llink: an element in the #GList
795 * Gets the position of the given element
796 * in the #GList (starting from 0).
798 * Returns: the position of the element in the #GList,
799 * or -1 if the element is not found
802 g_list_position (GList *list,
822 * @data: the data to find
824 * Gets the position of the element containing
825 * the given data (starting from 0).
827 * Returns: the index of the element containing the data,
828 * or -1 if the data is not found
831 g_list_index (GList *list,
839 if (list->data == data)
852 * Gets the last element in a #GList.
854 * Returns: the last element in the #GList,
855 * or %NULL if the #GList has no elements
858 g_list_last (GList *list)
873 * Gets the first element in a #GList.
875 * Returns: the first element in the #GList,
876 * or %NULL if the #GList has no elements
879 g_list_first (GList *list)
894 * Gets the number of elements in a #GList.
897 * This function iterates over the whole list to
898 * count its elements.
901 * Returns: the number of elements in the #GList
904 g_list_length (GList *list)
921 * @func: the function to call with each element's data
922 * @user_data: user data to pass to the function
924 * Calls a function for each element of a #GList.
928 * @data: the element's data.
929 * @user_data: user data passed to g_list_foreach() or
932 * Specifies the type of functions passed to g_list_foreach() and
936 g_list_foreach (GList *list,
942 GList *next = list->next;
943 (*func) (list->data, user_data);
949 g_list_insert_sorted_real (GList *list,
954 GList *tmp_list = list;
958 g_return_val_if_fail (func != NULL, list);
962 new_list = _g_list_alloc0 ();
963 new_list->data = data;
967 cmp = ((GCompareDataFunc) func) (data, tmp_list->data, user_data);
969 while ((tmp_list->next) && (cmp > 0))
971 tmp_list = tmp_list->next;
973 cmp = ((GCompareDataFunc) func) (data, tmp_list->data, user_data);
976 new_list = _g_list_alloc0 ();
977 new_list->data = data;
979 if ((!tmp_list->next) && (cmp > 0))
981 tmp_list->next = new_list;
982 new_list->prev = tmp_list;
988 tmp_list->prev->next = new_list;
989 new_list->prev = tmp_list->prev;
991 new_list->next = tmp_list;
992 tmp_list->prev = new_list;
994 if (tmp_list == list)
1001 * g_list_insert_sorted:
1002 * @list: a pointer to a #GList
1003 * @data: the data for the new element
1004 * @func: the function to compare elements in the list. It should
1005 * return a number > 0 if the first parameter comes after the
1006 * second parameter in the sort order.
1008 * Inserts a new element into the list, using the given comparison
1009 * function to determine its position.
1011 * Returns: the new start of the #GList
1014 g_list_insert_sorted (GList *list,
1018 return g_list_insert_sorted_real (list, data, (GFunc) func, NULL);
1022 * g_list_insert_sorted_with_data:
1023 * @list: a pointer to a #GList
1024 * @data: the data for the new element
1025 * @func: the function to compare elements in the list.
1026 * It should return a number > 0 if the first parameter
1027 * comes after the second parameter in the sort order.
1028 * @user_data: user data to pass to comparison function.
1030 * Inserts a new element into the list, using the given comparison
1031 * function to determine its position.
1033 * Returns: the new start of the #GList
1038 g_list_insert_sorted_with_data (GList *list,
1040 GCompareDataFunc func,
1043 return g_list_insert_sorted_real (list, data, (GFunc) func, user_data);
1047 g_list_sort_merge (GList *l1,
1052 GList list, *l, *lprev;
1060 cmp = ((GCompareDataFunc) compare_func) (l1->data, l2->data, user_data);
1076 l->next = l1 ? l1 : l2;
1083 g_list_sort_real (GList *list,
1097 while ((l2 = l2->next) != NULL)
1099 if ((l2 = l2->next) == NULL)
1106 return g_list_sort_merge (g_list_sort_real (list, compare_func, user_data),
1107 g_list_sort_real (l2, compare_func, user_data),
1115 * @compare_func: the comparison function used to sort the #GList.
1116 * This function is passed the data from 2 elements of the #GList
1117 * and should return 0 if they are equal, a negative value if the
1118 * first element comes before the second, or a positive value if
1119 * the first element comes after the second.
1121 * Sorts a #GList using the given comparison function.
1123 * Returns: the start of the sorted #GList
1128 * @b: a value to compare with.
1129 * @Returns: negative value if @a < @b; zero if @a = @b; positive
1132 * Specifies the type of a comparison function used to compare two
1133 * values. The function should return a negative integer if the first
1134 * value comes before the second, 0 if they are equal, or a positive
1135 * integer if the first value comes after the second.
1138 g_list_sort (GList *list,
1139 GCompareFunc compare_func)
1141 return g_list_sort_real (list, (GFunc) compare_func, NULL);
1146 * g_list_sort_with_data:
1148 * @compare_func: comparison function
1149 * @user_data: user data to pass to comparison function
1151 * Like g_list_sort(), but the comparison function accepts
1152 * a user data argument.
1154 * Returns: the new head of @list
1159 * @b: a value to compare with.
1160 * @user_data: user data to pass to comparison function.
1161 * @Returns: negative value if @a < @b; zero if @a = @b; positive
1164 * Specifies the type of a comparison function used to compare two
1165 * values. The function should return a negative integer if the first
1166 * value comes before the second, 0 if they are equal, or a positive
1167 * integer if the first value comes after the second.
1170 g_list_sort_with_data (GList *list,
1171 GCompareDataFunc compare_func,
1174 return g_list_sort_real (list, (GFunc) compare_func, user_data);