blob: 68c0e40749060af8c929f23be02a549bd4ffaaa8 [file] [log] [blame]
/* GLIB - Library of useful routines for C programming
* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
*
* SPDX-License-Identifier: LGPL-2.1-or-later
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
/*
* Modified by the GLib Team and others 1997-2000. See the AUTHORS
* file for a list of people on the GLib Team. See the ChangeLog
* files for a list of changes. These files are distributed with
* GLib at ftp://ftp.gtk.org/pub/gtk/.
*/
/*
* MT safe
*/
#include "config.h"
#include "gslist.h"
#include "gtestutils.h"
#include "gslice.h"
/**
* GSList:
* @data: holds the element's data, which can be a pointer to any kind
* of data, or any integer value using the
* [Type Conversion Macros][glib-Type-Conversion-Macros]
* @next: contains the link to the next element in the list.
*
* The #GSList struct is used for each element in the singly-linked
* list.
**/
/**
* g_slist_next:
* @slist: an element in a #GSList.
*
* A convenience macro to get the next element in a #GSList.
* Note that it is considered perfectly acceptable to access
* @slist->next directly.
*
* Returns: the next element, or %NULL if there are no more elements.
**/
#define _g_slist_alloc0() g_slice_new0 (GSList)
#define _g_slist_alloc() g_slice_new (GSList)
#define _g_slist_free1(slist) g_slice_free (GSList, slist)
/**
* g_slist_alloc:
*
* Allocates space for one #GSList element. It is called by the
* g_slist_append(), g_slist_prepend(), g_slist_insert() and
* g_slist_insert_sorted() functions and so is rarely used on its own.
*
* Returns: a pointer to the newly-allocated #GSList element.
**/
GSList*
g_slist_alloc (void)
{
return _g_slist_alloc0 ();
}
/**
* g_slist_free:
* @list: the first link of a #GSList
*
* Frees all of the memory used by a #GSList.
* The freed elements are returned to the slice allocator.
*
* If list elements contain dynamically-allocated memory,
* you should either use g_slist_free_full() or free them manually
* first.
*
* It can be combined with g_steal_pointer() to ensure the list head pointer
* is not left dangling:
* |[<!-- language="C" -->
* GSList *list_of_borrowed_things = …; /<!-- -->* (transfer container) *<!-- -->/
* g_slist_free (g_steal_pointer (&list_of_borrowed_things));
* ]|
*/
void
g_slist_free (GSList *list)
{
g_slice_free_chain (GSList, list, next);
}
/**
* g_slist_free_1:
* @list: a #GSList element
*
* Frees one #GSList element.
* It is usually used after g_slist_remove_link().
*/
/**
* g_slist_free1:
*
* A macro which does the same as g_slist_free_1().
*
* Since: 2.10
**/
void
g_slist_free_1 (GSList *list)
{
_g_slist_free1 (list);
}
/**
* g_slist_free_full:
* @list: the first link of a #GSList
* @free_func: the function to be called to free each element's data
*
* Convenience method, which frees all the memory used by a #GSList, and
* calls the specified destroy function on every element's data.
*
* @free_func must not modify the list (eg, by removing the freed
* element from it).
*
* It can be combined with g_steal_pointer() to ensure the list head pointer
* is not left dangling ­— this also has the nice property that the head pointer
* is cleared before any of the list elements are freed, to prevent double frees
* from @free_func:
* |[<!-- language="C" -->
* GSList *list_of_owned_things = …; /<!-- -->* (transfer full) (element-type GObject) *<!-- -->/
* g_slist_free_full (g_steal_pointer (&list_of_owned_things), g_object_unref);
* ]|
*
* Since: 2.28
**/
void
g_slist_free_full (GSList *list,
GDestroyNotify free_func)
{
g_slist_foreach (list, (GFunc) free_func, NULL);
g_slist_free (list);
}
/**
* g_slist_append:
* @list: a #GSList
* @data: the data for the new element
*
* Adds a new element on to the end of the list.
*
* The return value is the new start of the list, which may
* have changed, so make sure you store the new value.
*
* Note that g_slist_append() has to traverse the entire list
* to find the end, which is inefficient when adding multiple
* elements. A common idiom to avoid the inefficiency is to prepend
* the elements and reverse the list when all elements have been added.
*
* |[<!-- language="C" -->
* // Notice that these are initialized to the empty list.
* GSList *list = NULL, *number_list = NULL;
*
* // This is a list of strings.
* list = g_slist_append (list, "first");
* list = g_slist_append (list, "second");
*
* // This is a list of integers.
* number_list = g_slist_append (number_list, GINT_TO_POINTER (27));
* number_list = g_slist_append (number_list, GINT_TO_POINTER (14));
* ]|
*
* Returns: the new start of the #GSList
*/
GSList*
g_slist_append (GSList *list,
gpointer data)
{
GSList *new_list;
GSList *last;
new_list = _g_slist_alloc ();
new_list->data = data;
new_list->next = NULL;
if (list)
{
last = g_slist_last (list);
/* g_assert (last != NULL); */
last->next = new_list;
return list;
}
else
return new_list;
}
/**
* g_slist_prepend:
* @list: a #GSList
* @data: the data for the new element
*
* Adds a new element on to the start of the list.
*
* The return value is the new start of the list, which
* may have changed, so make sure you store the new value.
*
* |[<!-- language="C" -->
* // Notice that it is initialized to the empty list.
* GSList *list = NULL;
* list = g_slist_prepend (list, "last");
* list = g_slist_prepend (list, "first");
* ]|
*
* Returns: the new start of the #GSList
*/
GSList*
g_slist_prepend (GSList *list,
gpointer data)
{
GSList *new_list;
new_list = _g_slist_alloc ();
new_list->data = data;
new_list->next = list;
return new_list;
}
/**
* g_slist_insert:
* @list: a #GSList
* @data: the data for the new element
* @position: the position to insert the element.
* If this is negative, or is larger than the number
* of elements in the list, the new element is added on
* to the end of the list.
*
* Inserts a new element into the list at the given position.
*
* Returns: the new start of the #GSList
*/
GSList*
g_slist_insert (GSList *list,
gpointer data,
gint position)
{
GSList *prev_list;
GSList *tmp_list;
GSList *new_list;
if (position < 0)
return g_slist_append (list, data);
else if (position == 0)
return g_slist_prepend (list, data);
new_list = _g_slist_alloc ();
new_list->data = data;
if (!list)
{
new_list->next = NULL;
return new_list;
}
prev_list = NULL;
tmp_list = list;
while ((position-- > 0) && tmp_list)
{
prev_list = tmp_list;
tmp_list = tmp_list->next;
}
new_list->next = prev_list->next;
prev_list->next = new_list;
return list;
}
/**
* g_slist_insert_before:
* @slist: a #GSList
* @sibling: node to insert @data before
* @data: data to put in the newly-inserted node
*
* Inserts a node before @sibling containing @data.
*
* Returns: the new head of the list.
*/
GSList*
g_slist_insert_before (GSList *slist,
GSList *sibling,
gpointer data)
{
if (!slist)
{
slist = _g_slist_alloc ();
slist->data = data;
slist->next = NULL;
g_return_val_if_fail (sibling == NULL, slist);
return slist;
}
else
{
GSList *node, *last = NULL;
for (node = slist; node; last = node, node = last->next)
if (node == sibling)
break;
if (!last)
{
node = _g_slist_alloc ();
node->data = data;
node->next = slist;
return node;
}
else
{
node = _g_slist_alloc ();
node->data = data;
node->next = last->next;
last->next = node;
return slist;
}
}
}
/**
* g_slist_concat:
* @list1: a #GSList
* @list2: the #GSList to add to the end of the first #GSList
*
* Adds the second #GSList onto the end of the first #GSList.
* Note that the elements of the second #GSList are not copied.
* They are used directly.
*
* Returns: the start of the new #GSList
*/
GSList *
g_slist_concat (GSList *list1, GSList *list2)
{
if (list2)
{
if (list1)
g_slist_last (list1)->next = list2;
else
list1 = list2;
}
return list1;
}
static GSList*
_g_slist_remove_data (GSList *list,
gconstpointer data,
gboolean all)
{
GSList *tmp = NULL;
GSList **previous_ptr = &list;
while (*previous_ptr)
{
tmp = *previous_ptr;
if (tmp->data == data)
{
*previous_ptr = tmp->next;
g_slist_free_1 (tmp);
if (!all)
break;
}
else
{
previous_ptr = &tmp->next;
}
}
return list;
}
/**
* g_slist_remove:
* @list: a #GSList
* @data: the data of the element to remove
*
* Removes an element from a #GSList.
* If two elements contain the same data, only the first is removed.
* If none of the elements contain the data, the #GSList is unchanged.
*
* Returns: the new start of the #GSList
*/
GSList*
g_slist_remove (GSList *list,
gconstpointer data)
{
return _g_slist_remove_data (list, data, FALSE);
}
/**
* g_slist_remove_all:
* @list: a #GSList
* @data: data to remove
*
* Removes all list nodes with data equal to @data.
* Returns the new head of the list. Contrast with
* g_slist_remove() which removes only the first node
* matching the given data.
*
* Returns: new head of @list
*/
GSList*
g_slist_remove_all (GSList *list,
gconstpointer data)
{
return _g_slist_remove_data (list, data, TRUE);
}
static inline GSList*
_g_slist_remove_link (GSList *list,
GSList *link)
{
GSList *tmp = NULL;
GSList **previous_ptr = &list;
while (*previous_ptr)
{
tmp = *previous_ptr;
if (tmp == link)
{
*previous_ptr = tmp->next;
tmp->next = NULL;
break;
}
previous_ptr = &tmp->next;
}
return list;
}
/**
* g_slist_remove_link:
* @list: a #GSList
* @link_: an element in the #GSList
*
* Removes an element from a #GSList, without
* freeing the element. The removed element's next
* link is set to %NULL, so that it becomes a
* self-contained list with one element.
*
* Removing arbitrary nodes from a singly-linked list
* requires time that is proportional to the length of the list
* (ie. O(n)). If you find yourself using g_slist_remove_link()
* frequently, you should consider a different data structure,
* such as the doubly-linked #GList.
*
* Returns: the new start of the #GSList, without the element
*/
GSList*
g_slist_remove_link (GSList *list,
GSList *link_)
{
return _g_slist_remove_link (list, link_);
}
/**
* g_slist_delete_link:
* @list: a #GSList
* @link_: node to delete
*
* Removes the node link_ from the list and frees it.
* Compare this to g_slist_remove_link() which removes the node
* without freeing it.
*
* Removing arbitrary nodes from a singly-linked list requires time
* that is proportional to the length of the list (ie. O(n)). If you
* find yourself using g_slist_delete_link() frequently, you should
* consider a different data structure, such as the doubly-linked
* #GList.
*
* Returns: the new head of @list
*/
GSList*
g_slist_delete_link (GSList *list,
GSList *link_)
{
list = _g_slist_remove_link (list, link_);
_g_slist_free1 (link_);
return list;
}
/**
* g_slist_copy:
* @list: a #GSList
*
* Copies a #GSList.
*
* Note that this is a "shallow" copy. If the list elements
* consist of pointers to data, the pointers are copied but
* the actual data isn't. See g_slist_copy_deep() if you need
* to copy the data as well.
*
* Returns: a copy of @list
*/
GSList*
g_slist_copy (GSList *list)
{
return g_slist_copy_deep (list, NULL, NULL);
}
/**
* g_slist_copy_deep:
* @list: a #GSList
* @func: (scope call): a copy function used to copy every element in the list
* @user_data: user data passed to the copy function @func, or #NULL
*
* Makes a full (deep) copy of a #GSList.
*
* In contrast with g_slist_copy(), this function uses @func to make a copy of
* each list element, in addition to copying the list container itself.
*
* @func, as a #GCopyFunc, takes two arguments, the data to be copied
* and a @user_data pointer. On common processor architectures, it's safe to
* pass %NULL as @user_data if the copy function takes only one argument. You
* may get compiler warnings from this though if compiling with GCC’s
* `-Wcast-function-type` warning.
*
* For instance, if @list holds a list of GObjects, you can do:
* |[<!-- language="C" -->
* another_list = g_slist_copy_deep (list, (GCopyFunc) g_object_ref, NULL);
* ]|
*
* And, to entirely free the new list, you could do:
* |[<!-- language="C" -->
* g_slist_free_full (another_list, g_object_unref);
* ]|
*
* Returns: a full copy of @list, use g_slist_free_full() to free it
*
* Since: 2.34
*/
GSList*
g_slist_copy_deep (GSList *list, GCopyFunc func, gpointer user_data)
{
GSList *new_list = NULL;
if (list)
{
GSList *last;
new_list = _g_slist_alloc ();
if (func)
new_list->data = func (list->data, user_data);
else
new_list->data = list->data;
last = new_list;
list = list->next;
while (list)
{
last->next = _g_slist_alloc ();
last = last->next;
if (func)
last->data = func (list->data, user_data);
else
last->data = list->data;
list = list->next;
}
last->next = NULL;
}
return new_list;
}
/**
* g_slist_reverse:
* @list: a #GSList
*
* Reverses a #GSList.
*
* Returns: the start of the reversed #GSList
*/
GSList*
g_slist_reverse (GSList *list)
{
GSList *prev = NULL;
while (list)
{
GSList *next = list->next;
list->next = prev;
prev = list;
list = next;
}
return prev;
}
/**
* g_slist_nth:
* @list: a #GSList
* @n: the position of the element, counting from 0
*
* Gets the element at the given position in a #GSList.
*
* Returns: the element, or %NULL if the position is off
* the end of the #GSList
*/
GSList*
g_slist_nth (GSList *list,
guint n)
{
while (n-- > 0 && list)
list = list->next;
return list;
}
/**
* g_slist_nth_data:
* @list: a #GSList
* @n: the position of the element
*
* Gets the data of the element at the given position.
*
* Returns: the element's data, or %NULL if the position
* is off the end of the #GSList
*/
gpointer
g_slist_nth_data (GSList *list,
guint n)
{
while (n-- > 0 && list)
list = list->next;
return list ? list->data : NULL;
}
/**
* g_slist_find:
* @list: a #GSList
* @data: the element data to find
*
* Finds the element in a #GSList which
* contains the given data.
*
* Returns: the found #GSList element,
* or %NULL if it is not found
*/
GSList*
g_slist_find (GSList *list,
gconstpointer data)
{
while (list)
{
if (list->data == data)
break;
list = list->next;
}
return list;
}
/**
* g_slist_find_custom:
* @list: a #GSList
* @data: user data passed to the function
* @func: (scope call): the function to call for each element.
* It should return 0 when the desired element is found
*
* Finds an element in a #GSList, using a supplied function to
* find the desired element. It iterates over the list, calling
* the given function which should return 0 when the desired
* element is found. The function takes two #gconstpointer arguments,
* the #GSList element's data as the first argument and the
* given user data.
*
* Returns: the found #GSList element, or %NULL if it is not found
*/
GSList*
g_slist_find_custom (GSList *list,
gconstpointer data,
GCompareFunc func)
{
g_return_val_if_fail (func != NULL, list);
while (list)
{
if (! func (list->data, data))
return list;
list = list->next;
}
return NULL;
}
/**
* g_slist_position:
* @list: a #GSList
* @llink: an element in the #GSList
*
* Gets the position of the given element
* in the #GSList (starting from 0).
*
* Returns: the position of the element in the #GSList,
* or -1 if the element is not found
*/
gint
g_slist_position (GSList *list,
GSList *llink)
{
gint i;
i = 0;
while (list)
{
if (list == llink)
return i;
i++;
list = list->next;
}
return -1;
}
/**
* g_slist_index:
* @list: a #GSList
* @data: the data to find
*
* Gets the position of the element containing
* the given data (starting from 0).
*
* Returns: the index of the element containing the data,
* or -1 if the data is not found
*/
gint
g_slist_index (GSList *list,
gconstpointer data)
{
gint i;
i = 0;
while (list)
{
if (list->data == data)
return i;
i++;
list = list->next;
}
return -1;
}
/**
* g_slist_last:
* @list: a #GSList
*
* Gets the last element in a #GSList.
*
* This function iterates over the whole list.
*
* Returns: the last element in the #GSList,
* or %NULL if the #GSList has no elements
*/
GSList*
g_slist_last (GSList *list)
{
if (list)
{
while (list->next)
list = list->next;
}
return list;
}
/**
* g_slist_length:
* @list: a #GSList
*
* Gets the number of elements in a #GSList.
*
* This function iterates over the whole list to
* count its elements. To check whether the list is non-empty, it is faster to
* check @list against %NULL.
*
* Returns: the number of elements in the #GSList
*/
guint
g_slist_length (GSList *list)
{
guint length;
length = 0;
while (list)
{
length++;
list = list->next;
}
return length;
}
/**
* g_slist_foreach:
* @list: a #GSList
* @func: (scope call): the function to call with each element's data
* @user_data: user data to pass to the function
*
* Calls a function for each element of a #GSList.
*
* It is safe for @func to remove the element from @list, but it must
* not modify any part of the list after that element.
*/
void
g_slist_foreach (GSList *list,
GFunc func,
gpointer user_data)
{
while (list)
{
GSList *next = list->next;
(*func) (list->data, user_data);
list = next;
}
}
static GSList*
g_slist_insert_sorted_real (GSList *list,
gpointer data,
GFunc func,
gpointer user_data)
{
GSList *tmp_list = list;
GSList *prev_list = NULL;
GSList *new_list;
gint cmp;
g_return_val_if_fail (func != NULL, list);
if (!list)
{
new_list = _g_slist_alloc ();
new_list->data = data;
new_list->next = NULL;
return new_list;
}
cmp = ((GCompareDataFunc) func) (data, tmp_list->data, user_data);
while ((tmp_list->next) && (cmp > 0))
{
prev_list = tmp_list;
tmp_list = tmp_list->next;
cmp = ((GCompareDataFunc) func) (data, tmp_list->data, user_data);
}
new_list = _g_slist_alloc ();
new_list->data = data;
if ((!tmp_list->next) && (cmp > 0))
{
tmp_list->next = new_list;
new_list->next = NULL;
return list;
}
if (prev_list)
{
prev_list->next = new_list;
new_list->next = tmp_list;
return list;
}
else
{
new_list->next = list;
return new_list;
}
}
/**
* g_slist_insert_sorted:
* @list: a #GSList
* @data: the data for the new element
* @func: (scope call): the function to compare elements in the list.
* It should return a number > 0 if the first parameter
* comes after the second parameter in the sort order.
*
* Inserts a new element into the list, using the given
* comparison function to determine its position.
*
* Returns: the new start of the #GSList
*/
GSList*
g_slist_insert_sorted (GSList *list,
gpointer data,
GCompareFunc func)
{
return g_slist_insert_sorted_real (list, data, (GFunc) func, NULL);
}
/**
* g_slist_insert_sorted_with_data:
* @list: a #GSList
* @data: the data for the new element
* @func: (scope call): the function to compare elements in the list.
* It should return a number > 0 if the first parameter
* comes after the second parameter in the sort order.
* @user_data: data to pass to comparison function
*
* Inserts a new element into the list, using the given
* comparison function to determine its position.
*
* Returns: the new start of the #GSList
*
* Since: 2.10
*/
GSList*
g_slist_insert_sorted_with_data (GSList *list,
gpointer data,
GCompareDataFunc func,
gpointer user_data)
{
return g_slist_insert_sorted_real (list, data, (GFunc) func, user_data);
}
static GSList *
g_slist_sort_merge (GSList *l1,
GSList *l2,
GFunc compare_func,
gpointer user_data)
{
GSList list, *l;
gint cmp;
l=&list;
while (l1 && l2)
{
cmp = ((GCompareDataFunc) compare_func) (l1->data, l2->data, user_data);
if (cmp <= 0)
{
l=l->next=l1;
l1=l1->next;
}
else
{
l=l->next=l2;
l2=l2->next;
}
}
l->next= l1 ? l1 : l2;
return list.next;
}
static GSList *
g_slist_sort_real (GSList *list,
GFunc compare_func,
gpointer user_data)
{
GSList *l1, *l2;
if (!list)
return NULL;
if (!list->next)
return list;
l1 = list;
l2 = list->next;
while ((l2 = l2->next) != NULL)
{
if ((l2 = l2->next) == NULL)
break;
l1=l1->next;
}
l2 = l1->next;
l1->next = NULL;
return g_slist_sort_merge (g_slist_sort_real (list, compare_func, user_data),
g_slist_sort_real (l2, compare_func, user_data),
compare_func,
user_data);
}
/**
* g_slist_sort:
* @list: a #GSList
* @compare_func: (scope call): the comparison function used to sort the #GSList.
* This function is passed the data from 2 elements of the #GSList
* and should return 0 if they are equal, a negative value if the
* first element comes before the second, or a positive value if
* the first element comes after the second.
*
* Sorts a #GSList using the given comparison function. The algorithm
* used is a stable sort.
*
* Returns: the start of the sorted #GSList
*/
GSList *
g_slist_sort (GSList *list,
GCompareFunc compare_func)
{
return g_slist_sort_real (list, (GFunc) compare_func, NULL);
}
/**
* g_slist_sort_with_data:
* @list: a #GSList
* @compare_func: (scope call): comparison function
* @user_data: data to pass to comparison function
*
* Like g_slist_sort(), but the sort function accepts a user data argument.
*
* Returns: new head of the list
*/
GSList *
g_slist_sort_with_data (GSList *list,
GCompareDataFunc compare_func,
gpointer user_data)
{
return g_slist_sort_real (list, (GFunc) compare_func, user_data);
}
/**
* g_clear_slist: (skip)
* @slist_ptr: (not nullable): a #GSList return location
* @destroy: (nullable): the function to pass to g_slist_free_full() or %NULL to not free elements
*
* Clears a pointer to a #GSList, freeing it and, optionally, freeing its elements using @destroy.
*
* @slist_ptr must be a valid pointer. If @slist_ptr points to a null #GSList, this does nothing.
*
* Since: 2.64
*/
void
(g_clear_slist) (GSList **slist_ptr,
GDestroyNotify destroy)
{
GSList *slist;
slist = *slist_ptr;
if (slist)
{
*slist_ptr = NULL;
if (destroy)
g_slist_free_full (slist, destroy);
else
g_slist_free (slist);
}
}