Tizen Native API  5.5
Functions | Typedefs | Defines
List
Containers

These functions provide double linked list management.

Eina_List is a doubly linked list. It can store data of any type in the form of void pointers. It has convenience functions to do all the common operations which means it should rarely if ever be necessary to directly access the struct's fields. Nevertheless it can be useful to understand the inner workings of the data structure being used.

Eina_List nodes keep references to the previous node, the next node, its data and to an accounting structure.

eina_list.png

Eina_List_Accounting is used to improve the performance of some functions. It is private and should not be modified. It contains a reference to the end of the list and the number of elements in the list.

Note:
Every function that modifies the contents of the list returns a pointer to the head of the list and it is essential that this be pointer be used in any future references to the list.

Most functions have two versions that have the same effect but operate on different arguments, the plain functions operate over data(e.g..: eina_list_append_relative, eina_list_remove, eina_list_data_find), the list versions of these functions operate on Eina_List nodes.

Warning:
You must always use the pointer to the first element of the list as the list!
You must never use a pointer to an element in the middle of the list as the list!

Here are some examples of Eina_List usage:

Functions

Eina_List * eina_list_append (Eina_List *list, const void *data)
 Appends the given data to the given linked list.
Eina_List * eina_list_prepend (Eina_List *list, const void *data)
 Prepends the given data to the given linked list.
Eina_List * eina_list_append_relative (Eina_List *list, const void *data, const void *relative)
 Inserts the given data into the given linked list after the specified data.
Eina_List * eina_list_append_relative_list (Eina_List *list, const void *data, Eina_List *relative)
 Appends a list node to a linked list after the specified member.
Eina_List * eina_list_prepend_relative (Eina_List *list, const void *data, const void *relative)
 Prepends a data pointer to a linked list before the specified member.
Eina_List * eina_list_prepend_relative_list (Eina_List *list, const void *data, Eina_List *relative)
 Prepends a list node to a linked list before the specified member.
Eina_List * eina_list_sorted_insert (Eina_List *list, Eina_Compare_Cb func, const void *data)
 Inserts a new node into a sorted list.
Eina_List * eina_list_remove (Eina_List *list, const void *data)
 Removes the first instance of the specified data from the given list.
Eina_List * eina_list_remove_list (Eina_List *list, Eina_List *remove_list)
 Removes the specified list node.
Eina_List * eina_list_promote_list (Eina_List *list, Eina_List *move_list)
 Moves the specified data to the head of the list.
Eina_List * eina_list_demote_list (Eina_List *list, Eina_List *move_list)
 Moves the specified data to the tail of the list.
void * eina_list_data_find (const Eina_List *list, const void *data)
 Finds a member of a list and returns it.
Eina_List * eina_list_data_find_list (const Eina_List *list, const void *data)
 Finds a member of a list and returns it as a list node.
Eina_Bool eina_list_move (Eina_List **to, Eina_List **from, void *data)
 Moves a data pointer from one list to another.
Eina_Bool eina_list_move_list (Eina_List **to, Eina_List **from, Eina_List *data)
 Moves a list node from one list to another.
Eina_List * eina_list_free (Eina_List *list)
 Frees an entire list and all the nodes, ignoring the data contained.
void * eina_list_nth (const Eina_List *list, unsigned int n)
 Gets the nth member's data pointer in a list, or NULL on error.
Eina_List * eina_list_nth_list (const Eina_List *list, unsigned int n)
 Gets the nth member's list node in a list.
Eina_List * eina_list_reverse (Eina_List *list)
 Reverses all the elements in the list.
Eina_List * eina_list_reverse_clone (const Eina_List *list)
 Clones (copies) all the elements in the list in reverse order.
Eina_List * eina_list_clone (const Eina_List *list)
 Clones (copies) all the elements in the list in exactly same order.
Eina_List * eina_list_sort (Eina_List *list, unsigned int limit, Eina_Compare_Cb func)
 Sorts a list according to the ordering func will return.
Eina_List * eina_list_shuffle (Eina_List *list, Eina_Random_Cb func)
 Shuffles list.
Eina_List * eina_list_merge (Eina_List *left, Eina_List *right)
 Merges two list.
Eina_List * eina_list_sorted_merge (Eina_List *left, Eina_List *right, Eina_Compare_Cb func)
 Merges two sorted list according to the ordering func will return.
Eina_List * eina_list_split_list (Eina_List *list, Eina_List *relative, Eina_List **right)
 Splits a list into 2 lists.
Eina_List * eina_list_search_sorted_near_list (const Eina_List *list, Eina_Compare_Cb func, const void *data, int *result_cmp)
 Returns node nearest to data from the sorted list.
Eina_List * eina_list_search_sorted_list (const Eina_List *list, Eina_Compare_Cb func, const void *data)
 Returns node if data is in the sorted list.
void * eina_list_search_sorted (const Eina_List *list, Eina_Compare_Cb func, const void *data)
 Returns node data if it is in the sorted list.
Eina_List * eina_list_search_unsorted_list (const Eina_List *list, Eina_Compare_Cb func, const void *data)
 Returns node if data is in the unsorted list.
void * eina_list_search_unsorted (const Eina_List *list, Eina_Compare_Cb func, const void *data)
 Returns node data if it is in the unsorted list.
static Eina_List * eina_list_last (const Eina_List *list)
 Gets the last list node in the list.
static Eina_List * eina_list_next (const Eina_List *list)
 Gets the next list node after the specified list node.
static Eina_List * eina_list_prev (const Eina_List *list)
 Gets the list node prior to the specified list node.
static void * eina_list_data_get (const Eina_List *list)
 Gets the list node data member.
static void * eina_list_data_set (Eina_List *list, const void *data)
 Sets the list node data member.
static unsigned int eina_list_count (const Eina_List *list)
 Gets the count of the number of items in a list.
static void * eina_list_last_data_get (const Eina_List *list)
 Returns the last list node's data.
Eina_Iterator * eina_list_iterator_new (const Eina_List *list)
 Returns a new iterator associated with a list.
Eina_Iterator * eina_list_iterator_reversed_new (const Eina_List *list)
 Returns a new reversed iterator associated with a list.
Eina_Accessor * eina_list_accessor_new (const Eina_List *list)
 Returns a new accessor associated with a list.
int eina_list_data_idx (const Eina_List *list, void *data)
 Finds the member of the list and returns the index.

Typedefs

typedef struct _Eina_List Eina_List
typedef struct
_Eina_List_Accounting 		Eina_List_Accounting

Defines

#define EINA_LIST_FOREACH(list, l, data)
 Definition for the macro to iterate over a list.
#define EINA_LIST_REVERSE_FOREACH(list, l, _data)
 Definition for the macro to iterate over a list in the reverse order.
#define EINA_LIST_FOREACH_SAFE(list, l, l_next, data)
 Definition for the macro to iterate over a list with support for node deletion.
#define EINA_LIST_REVERSE_FOREACH_SAFE(list, l, l_prev, data)
 Definition for the macro to iterate over a list in the reverse order with support for deletion.
#define EINA_LIST_FREE(list, data)
 Definition for the macro to remove each list node while having access to each node's data.

Define Documentation

#define EINA_LIST_FOREACH (   list,
  l,
  data 
)
Value:
for (l = list,                         \
       data = eina_list_data_get(l);     \
       l;                                \
       l = eina_list_next(l),            \
       data = eina_list_data_get(l))

Definition for the macro to iterate over a list.

Parameters:
[in]listThe list to iterate over.
[out]lA list that is used as an iterator and points to the current node.
[out]dataCurrent item's data.

This macro iterates over list from the first element to the last. data is the data related to the current element. l is an Eina_List used as the list iterator.

The following diagram illustrates this macro iterating over a list of four elements("one", "two", "three" and "four"):

eina-list-foreach.png

It can be used to free list data, as in the following example:

 Eina_List *list;
 Eina_List *l;
 char      *data;

 // list is already filled,
 // its elements are just duplicated strings,
 // EINA_LIST_FOREACH will be used to free those strings

 EINA_LIST_FOREACH(list, l, data)
   free(data);
 eina_list_free(list);
Note:
This is not the optimal way to release memory allocated to a list, since it iterates over the list twice. For an optimized algorithm, use EINA_LIST_FREE().
Warning:
list must be a pointer to the first element of the list.
Be careful when deleting list nodes. If you remove the current node and continue iterating, the code will fail because the macro will not be able to get the next node. Notice that it's OK to remove any node if you stop the loop after that. For destructive operations such as this, consider using EINA_LIST_FOREACH_SAFE().
Examples:
diskselector_example_02.c, ecore_con_server_simple_example.c, ecore_con_url_cookies_example.c, ecore_con_url_headers_example.c, ecore_evas_basics_example.c, ecore_imf_example.c, edje-box2.c, eina_inlist_02.c, eina_list_01.c, entry_example.c, evas-box.c, evas-buffer-simple.c, evas-events.c, evas-init-shutdown.c, gengrid_example.c, genlist_example_02.c, genlist_example_05.c, hoversel_example_01.c, list_example_03.c, slideshow_example.c, and transit_example_04.c.
#define EINA_LIST_FOREACH_SAFE (   list,
  l,
  l_next,
  data 
)
Value:
for (l = list,                                      \
       l_next = eina_list_next(l),                    \
       EINA_PREFETCH(l_next),                         \
       data = eina_list_data_get(l);                  \
       EINA_PREFETCH(data),                           \
       l;                                             \
       l = l_next,                                    \
       l_next = eina_list_next(l),                    \
       EINA_PREFETCH(l_next),                         \
       data = eina_list_data_get(l),                  \
       EINA_PREFETCH(data))

Definition for the macro to iterate over a list with support for node deletion.

Parameters:
[in]listThe list to iterate over.
[out]lA list that is used as an iterator and points to the current node.
[out]l_nextA list that is used as an iterator and points to the next node.
[out]dataCurrent item's data.

This macro iterates over list from the first element to the last. data is the data related to the current element. l is an Eina_List used as the list iterator.

Since this macro stores a pointer to the next list node in l_next, deleting the current node and continuing looping is safe.

The following diagram illustrates this macro iterating over a list of four elements ("one", "two", "three" and "four"):

eina-list-foreach-safe.png

This macro can be used to free list nodes, as in the following example:

 Eina_List *list;
 Eina_List *l;
 Eina_List *l_next;
 char      *data;

 // list is already filled,
 // its elements are just duplicated strings,
 // EINA_LIST_FOREACH_SAFE will be used to free elements that match "key".

 EINA_LIST_FOREACH_SAFE(list, l, l_next, data)
   if (strcmp(data, "key") == 0)
     {
        free(data);
        list = eina_list_remove_list(list, l);
     }
Warning:
list must be a pointer to the first element of the list.
Examples:
eina_inlist_02.c.
#define EINA_LIST_FREE (   list,
  data 
)
Value:
for (data = eina_list_data_get(list),          \
       list ? EINA_PREFETCH(((Eina_List *)list)->next) : EINA_PREFETCH(list); \
       list;                                     \
       list = eina_list_remove_list(list, list), \
       list ? EINA_PREFETCH(((Eina_List *)list)->next) : EINA_PREFETCH(list), \
       data = eina_list_data_get(list))

Definition for the macro to remove each list node while having access to each node's data.

Parameters:
[in,out]listThe list that will be cleared.
[out]dataCurrent node's data.

This macro will call eina_list_remove_list for each list node, and store the data contained in the current node in data.

The following diagram illustrates this macro iterating over a list of four elements ("one", "two", "three" and "four"):

eina-list-free.png

If you do not need to release node data, it is easier to call eina_list_free().

 Eina_List *list;
 char      *data;

 // list is already filled,
 // its elements are just duplicated strings,

 EINA_LIST_FREE(list, data)
   free(data);
Warning:
list must be a pointer to the first element of the list.
See also:
eina_list_free()
Examples:
ecore_imf_example.c, ecore_thread_example.c, edje-color-class.c, efl_thread_6.c, eina_list_04.c, eina_tiler_01.c, genlist_example_02.c, and genlist_example_05.c.
#define EINA_LIST_REVERSE_FOREACH (   list,
  l,
  _data 
)
Value:
for (l = eina_list_last(list),                 \
       _data = eina_list_data_get(l),            \
       l ? (EINA_PREFETCH(((Eina_List *)l)->prev), EINA_PREFETCH(_data)) : EINA_PREFETCH(l); \
       l;                                        \
       l = eina_list_prev(l),                    \
       _data = eina_list_data_get(l),            \
       l ? (EINA_PREFETCH(((Eina_List *)l)->prev), EINA_PREFETCH(_data)) : EINA_PREFETCH(l))

Definition for the macro to iterate over a list in the reverse order.

Parameters:
[in]listThe list to iterate over.
[out]lA list that is used as an iterator and points to the current node.
[out]dataCurrent item's data.

This macro works like EINA_LIST_FOREACH, but iterates from the last element of a list to the first. data is the data related to the current element, while l is an Eina_List that is used as the list iterator.

The following diagram illustrates this macro iterating over a list of four elements("one", "two", "three" and "four"):

eina-list-reverse-foreach.png

It can be used to free list data, as in the following example:

 Eina_List *list;
 Eina_List *l;
 char      *data;

 // list is already filled,
 // its elements are just duplicated strings,
 // EINA_LIST_REVERSE_FOREACH will be used to free those strings

 EINA_LIST_REVERSE_FOREACH(list, l, data)
   free(data);
 eina_list_free(list);
Note:
This is not the optimal way to release memory allocated to a list, since it iterates over the list twice. For an optimized algorithm, use EINA_LIST_FREE().
Warning:
list must be a pointer to the first element of the list.
Be careful when deleting list nodes. If you remove the current node and continue iterating, the code will fail because the macro will not be able to get the next node. Notice that it's OK to remove any node if you stop the loop after that. For destructive operations such as this, consider using EINA_LIST_REVERSE_FOREACH_SAFE().
#define EINA_LIST_REVERSE_FOREACH_SAFE (   list,
  l,
  l_prev,
  data 
)
Value:
for (l = eina_list_last(list),                              \
       l_prev = eina_list_prev(l),                            \
       EINA_PREFETCH(l_prev),                                 \
       data = eina_list_data_get(l);                          \
       EINA_PREFETCH(data),                                   \
       l;                                                     \
       l = l_prev,                                            \
       l_prev = eina_list_prev(l),                            \
       EINA_PREFETCH(l_prev),                                 \
       data = eina_list_data_get(l),                          \
       EINA_PREFETCH(data))

Definition for the macro to iterate over a list in the reverse order with support for deletion.

Parameters:
[in]listThe list to iterate over.
[out]lA list that is used as an iterator and points to the current node.
[out]l_prevA list that is used as an iterator and points to the previous node.
[out]dataCurrent item's data.

This macro works like EINA_LIST_FOREACH_SAFE, but iterates from the last element of a list to the first. data is the data related to the current element, while l is an Eina_List that is used as the list iterator.

Since this macro stores a pointer to the previous list node in l_prev, deleting the current node and continuing looping is safe.

The following diagram illustrates this macro iterating over a list of four elements ("one", "two", "three" and "four"):

eina-list-reverse-foreach-safe.png

This macro can be used to free list nodes, as in the following example:

 Eina_List *list;
 Eina_List *l;
 Eina_List *l_prev;
 char       *data;

 // list is already filled,
 // its elements are just duplicated strings,
 // EINA_LIST_REVERSE_FOREACH_SAFE will be used to free elements that match "key".

 EINA_LIST_REVERSE_FOREACH_SAFE(list, l, l_prev, data)
   if (strcmp(data, "key") == 0)
     {
        free(data);
        list = eina_list_remove_list(list, l);
     }
Warning:
list must be a pointer to the first element of the list.

Typedef Documentation

Eina_List

Type for a generic double linked list.

Eina_List_Accounting

Cache used to store the last element of a list and the number of elements, for fast access.

Function Documentation

Eina_Accessor* eina_list_accessor_new ( const Eina_List *  list)

Returns a new accessor associated with a list.

Parameters:
[in]listThe list.
Returns:
A new accessor, or NULL on error.

This function returns a newly allocated accessor associated with list. If list is NULL or the count member of list is less or equal than 0, this function returns NULL. If the memory can not be allocated, NULL is returned; otherwise, a valid accessor is returned.

Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
eina_accessor_01.c.
Eina_List* eina_list_append ( Eina_List *  list,
const void *  data 
)

Appends the given data to the given linked list.

Parameters:
[in,out]listThe given list.
[in]dataThe data to append.
Returns:
A list pointer, or NULL on error.

This function appends data to list. If list is NULL, a new list is returned. On success, a new list pointer that should be used in place of the one given to this function is returned. Otherwise, the old pointer is returned.

The following example code demonstrates how to ensure that the given data has been successfully appended.

 Eina_List *list = NULL;
 extern void *my_data;

 list = eina_list_append(list, my_data);
Warning:
list must be a pointer to the first element of the list(or NULL).
Since :
2.3
Examples:
box_example_02.c, ecore_thread_example.c, efl_thread_6.c, eina_accessor_01.c, eina_iterator_01.c, eina_list_01.c, eina_list_02.c, eina_list_03.c, eina_list_04.c, eina_tiler_01.c, genlist_example_05.c, map_example_02.c, and transit_example_04.c.
Eina_List* eina_list_append_relative ( Eina_List *  list,
const void *  data,
const void *  relative 
)

Inserts the given data into the given linked list after the specified data.

Parameters:
[in,out]listThe given linked list.
[in]dataThe data to insert.
[in]relativeThe data to insert after.
Returns:
A list pointer, or NULL on error.

This function inserts data into list after relative. If relative is not in the list, data is appended to the list. If list is NULL, a new list is returned. If there are multiple instances of relative in the list, data is inserted after the first instance. On success, a new list pointer that should be used in place of the one given to this function is returned. Otherwise, the old pointer is returned.

The following example code demonstrates how to ensure that the given data has been successfully inserted.

 Eina_List *list = NULL;
 extern void *my_data;
 extern void *relative_member;

 list = eina_list_append(list, relative_member);
 list = eina_list_append_relative(list, my_data, relative_member);
Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
eina_list_01.c.
Eina_List* eina_list_append_relative_list ( Eina_List *  list,
const void *  data,
Eina_List *  relative 
)

Appends a list node to a linked list after the specified member.

Parameters:
[in,out]listThe given linked list.
[in]dataThe data to insert.
[in]relativeThe list node to insert after.
Returns:
A list pointer, or NULL on error.

This function inserts data into list after the list node relative. If list or relative are NULL, data is just appended to list using eina_list_append(). If list is NULL, a new list is returned. If there are multiple instances of relative in the list, data is inserted after the first instance. On success, a new list pointer that should be used in place of the one given to this function is returned. Otherwise, the old pointer is returned.

Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
eina_list_01.c, and eina_list_02.c.
Eina_List* eina_list_clone ( const Eina_List *  list)

Clones (copies) all the elements in the list in exactly same order.

Parameters:
[in]listThe list to clone.
Returns:
The new list that has been cloned, or NULL on error.

This function clone in order of all elements in list. If list is NULL, this function returns NULL. This returns a copy of the given list.

Note:
copy: this will copy the list and you should then eina_list_free() when it is not required anymore.
Warning:
list must be a pointer to the first element of the list.
See also:
eina_list_reverse_clone()
Since :
2.3
static unsigned int eina_list_count ( const Eina_List *  list) [static]

Gets the count of the number of items in a list.

Parameters:
[in]listThe list whose count to return.
Returns:
The number of members in the list.

This function returns the quantity of members that list contains. If the list is NULL, 0 is returned.

NB: This is an order-1 operation and takes the same time regardless of the length of the list.

Warning:
list must be a pointer to the first element of the list.
Examples:
ecore_con_server_simple_example.c, ecore_thread_example.c, edje-box2.c, eina_inlist_02.c, eina_list_03.c, evas-box.c, genlist_example_02.c, and genlist_example_05.c.
void* eina_list_data_find ( const Eina_List *  list,
const void *  data 
)

Finds a member of a list and returns it.

Parameters:
[in]listThe linked list to search.
[in]dataThe data member to find in the list.
Returns:
The data member pointer if found, or NULL otherwise.

This function searches in list from beginning to end for the first member whose data pointer is data. If it is found, data will be returned, otherwise NULL will be returned.

Example: 

 extern Eina_List *list;
 extern void *my_data;

 if (eina_list_data_find(list, my_data) == my_data)
   {
      printf("Found member %p\n", my_data);
   }
Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Eina_List* eina_list_data_find_list ( const Eina_List *  list,
const void *  data 
)

Finds a member of a list and returns it as a list node.

Parameters:
[in]listThe list to search for data.
[in]dataThe data pointer to find in the list.
Returns:
A list node containing the data member on success, NULL otherwise.

This function searches list from beginning to end for the first member whose data pointer is data. If it is found, the list node containing the specified member is returned, otherwise NULL is returned.

Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
eina_list_03.c.
static void* eina_list_data_get ( const Eina_List *  list) [static]

Gets the list node data member.

Parameters:
[in]listThe list node to get the data member of.
Returns:
The data member from the list node.

This function returns the data member of the specified list node list. It is equivalent to list->data. If list is NULL, this function returns NULL.

Warning:
list must be a pointer to the first element of the list.
Examples:
box_example_02.c, eina_list_04.c, menu_example_01.c, and slideshow_example.c.
int eina_list_data_idx ( const Eina_List *  list,
void *  data 
)

Finds the member of the list and returns the index.

Parameters:
[in]listThe list.
[in]dataThe data member.
Returns:
The index of data member if found, -1 otherwise.

This function searches in list from beginning to end for the first member whose data pointer is data. If it is found, the index of the data will be returned, otherwise -1 will be returned.

Warning:
list must be a pointer to the first element of the list.
Since (EFL) :
1.14
Since :
3.0
static void* eina_list_data_set ( Eina_List *  list,
const void *  data 
) [static]

Sets the list node data member.

Parameters:
[in,out]listThe list node to set the data member of.
[in]dataThe data to be set.
Returns:
The previous data value.

This function sets the data member data of the specified list node list. It returns the previous data of the node. If list is NULL, this function returns NULL.

Warning:
list must be a pointer to the first element of the list.
Examples:
eina_list_03.c.
Eina_List* eina_list_demote_list ( Eina_List *  list,
Eina_List *  move_list 
)

Moves the specified data to the tail of the list.

Parameters:
[in,out]listThe given linked list.
[in]move_listThe list node to move.
Returns:
A new list handle to replace the old one, or NULL on error.

This function move move_list to the end of list. If list is NULL, NULL is returned. If move_list is NULL, list is returned. Otherwise, a new list pointer that should be used in place of the one passed to this function is returned.

Example: 

 extern Eina_List *list;
 Eina_List *l;
 extern void *my_data;
 void *data;

 EINA_LIST_FOREACH(list, l, data)
   {
      if (data == my_data)
        {
           list = eina_list_demote_list(list, l);
           break;
        }
   }
Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
box_example_02.c, and eina_list_03.c.
Eina_List* eina_list_free ( Eina_List *  list)

Frees an entire list and all the nodes, ignoring the data contained.

Parameters:
[in,out]listThe list to free.
Returns:
A NULL pointer.

This function frees all the nodes of list. It does not free the data of the nodes. To free them, use EINA_LIST_FREE.

Since :
2.3
Examples:
box_example_02.c, eina_accessor_01.c, eina_inlist_02.c, eina_iterator_01.c, eina_list_01.c, eina_list_02.c, eina_list_03.c, eina_tiler_01.c, and evas-box.c.
Eina_Iterator* eina_list_iterator_new ( const Eina_List *  list)

Returns a new iterator associated with a list.

Parameters:
[in]listThe list.
Returns:
A new iterator, or NULL on memory allocation failure.

This function returns a newly allocated iterator associated with list. If list is NULL or the count member of list is less than or equal to 0, this function still returns a valid iterator that will always return false on eina_iterator_next(), thus keeping API sane.

Warning:
list must be a pointer to the first element of the list.
if the list structure changes then the iterator becomes invalid! That is, if you add or remove nodes this iterator behavior is undefined and your program may crash!
Since :
2.3
Examples:
eina_iterator_01.c, and eina_list_03.c.
Eina_Iterator* eina_list_iterator_reversed_new ( const Eina_List *  list)

Returns a new reversed iterator associated with a list.

Parameters:
[in]listThe list.
Returns:
A new iterator, or NULL on memory allocation failure.

This function returns a newly allocated iterator associated with list. If list is NULL or the count member of list is less than or equal to 0, this function still returns a valid iterator that will always return false on eina_iterator_next(), thus keeping API sane.

Unlike eina_list_iterator_new(), this will walk the list backwards.

Warning:
list must be a pointer to the first element of the list.
if the list structure changes then the iterator becomes invalid! That is, if you add or remove nodes this iterator behavior is undefined and your program may crash!
Since :
2.3
static Eina_List* eina_list_last ( const Eina_List *  list) [static]

Gets the last list node in the list.

Parameters:
[in]listThe list to get the last list node from.
Returns:
The last list node in the list.

This function returns the last list node in the list list. If list is NULL or empty, NULL is returned.

This is a order-1 operation (it takes the same short time regardless of the length of the list).

Warning:
list must be a pointer to the first element of the list.
Examples:
eina_list_04.c.
static void* eina_list_last_data_get ( const Eina_List *  list) [static]

Returns the last list node's data.

Parameters:
[in]listThe list.
Returns:
The node's data, or NULL on being passed a NULL pointer

This function is a shortcut for typing eina_list_data_get(eina_list_last())

Since (EFL) :
1.8
Eina_List* eina_list_merge ( Eina_List *  left,
Eina_List *  right 
)

Merges two list.

Parameters:
[in]leftHead list to merge.
[in]rightTail list to merge.
Returns:
A new merged list.

This function puts right at the end of left and returns the head.

Both left and right do not exist anymore after the merge.

Note:
Merge cost is O(n), being n the size of the smallest list. This is due the need to fix accounting of that segment, making count and last access O(1).
Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Eina_Bool eina_list_move ( Eina_List **  to,
Eina_List **  from,
void *  data 
)

Moves a data pointer from one list to another.

Parameters:
[in,out]toThe list to move the data to.
[in,out]fromThe list to move from.
[in]dataThe data member to move.
Returns:
EINA_TRUE on success, EINA_FALSE otherwise.

This function is a shortcut for doing the following: to = eina_list_append(to, data); from = eina_list_remove(from, data);

Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Eina_Bool eina_list_move_list ( Eina_List **  to,
Eina_List **  from,
Eina_List *  data 
)

Moves a list node from one list to another.

Parameters:
[in,out]toThe list to move the data to.
[in,out]fromThe list to move from.
[in]dataThe list node containing the data to move.
Returns:
EINA_TRUE on success, EINA_FALSE otherwise.

This function is a shortcut for doing the following: to = eina_list_append(to, data->data); from = eina_list_remove_list(from, data);

Warning:
list must be a pointer to the first element of the list.
Since :
2.3
static Eina_List* eina_list_next ( const Eina_List *  list) [static]

Gets the next list node after the specified list node.

Parameters:
[in]listThe list node to get the next list node from
Returns:
The next list node on success, NULL otherwise.

This function returns the next list node after the current one in list. It is equivalent to list->next. If list is NULL or if no next list node exists, it returns NULL.

Warning:
list must be a pointer to the first element of the list.
Examples:
eina_list_04.c.
void* eina_list_nth ( const Eina_List *  list,
unsigned int  n 
)

Gets the nth member's data pointer in a list, or NULL on error.

Parameters:
[in]listThe list to get the specified member number from.
[in]nThe number of the element (0 being the first).
Returns:
The data pointer stored in the specified element.

This function returns the data pointer of element number n, in the list. The first element in the array is element number 0. If the element number n does not exist, NULL is returned. Otherwise, the data of the found element is returned.

Note:
Worst case is O(n).
Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
evas-box.c.
Eina_List* eina_list_nth_list ( const Eina_List *  list,
unsigned int  n 
)

Gets the nth member's list node in a list.

Parameters:
[in]listThe list to get the specified member number from.
[in]nThe number of the element (0 being the first).
Returns:
The list node stored in the numbered element, or NULL on error.

This function returns the list node of element number n, in list. The first element in the array is element number 0. If the element number n does not exist or list is NULL or n is greater than the count of elements in list minus 1, NULL is returned. Otherwise the list node stored in the numbered element is returned.

Note:
Worst case is O(n).
Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
eina_list_01.c, and eina_list_03.c.
Eina_List* eina_list_prepend ( Eina_List *  list,
const void *  data 
)

Prepends the given data to the given linked list.

Parameters:
[in,out]listThe given list.
[in]dataThe data to prepend.
Returns:
A list pointer, or NULL on error.

This function prepends data to list. If list is NULL, a new list is returned. On success, a new list pointer that should be used in place of the one given to this function is returned. Otherwise, the old pointer is returned.

The following example code demonstrates how to ensure that the given data has been successfully prepended.

Example: 

 Eina_List *list = NULL;
 extern void *my_data;

 list = eina_list_prepend(list, my_data);
Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
eina_inlist_02.c, and eina_list_01.c.
Eina_List* eina_list_prepend_relative ( Eina_List *  list,
const void *  data,
const void *  relative 
)

Prepends a data pointer to a linked list before the specified member.

Parameters:
[in,out]listThe given linked list.
[in]dataThe data to insert.
[in]relativeThe member that data will be inserted before.
Returns:
A list pointer, or NULL on error.

This function inserts data to list before relative. If relative is not in the list, data is prepended to the list with eina_list_prepend(). If list is NULL, a new list is returned. If there are multiple instances of relative in the list, data is inserted before the first instance. On success, a new list pointer that should be used in place of the one given to this function is returned. Otherwise, the old pointer is returned.

The following code example demonstrates how to ensure that the given data has been successfully inserted.

 Eina_List *list = NULL;
 extern void *my_data;
 extern void *relative_member;

 list = eina_list_append(list, relative_member);
 list = eina_list_prepend_relative(list, my_data, relative_member);
Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
eina_list_01.c.
Eina_List* eina_list_prepend_relative_list ( Eina_List *  list,
const void *  data,
Eina_List *  relative 
)

Prepends a list node to a linked list before the specified member.

Parameters:
[in,out]listThe given linked list.
[in]dataThe data to insert.
[in]relativeThe list node to insert before.
Returns:
A list pointer, or NULL on error.

This function inserts data to list before the list node relative. If list or relative are NULL, data is just prepended to list using eina_list_prepend(). If list is NULL, a new list is returned. If there are multiple instances of relative in the list, data is inserted before the first instance. On success, a new list pointer that should be used in place of the one given to this function is returned. Otherwise, the old pointer is returned.

Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
eina_list_01.c, and eina_list_02.c.
static Eina_List* eina_list_prev ( const Eina_List *  list) [static]

Gets the list node prior to the specified list node.

Parameters:
[in]listThe list node to get the previous list node from.
Returns:
The previous list node on success, NULL otherwise.

This function returns the previous list node before the current one in list. It is equivalent to list->prev. If list is NULL or if no previous list node exists, it returns NULL.

Warning:
list must be a pointer to the first element of the list.
Examples:
eina_list_04.c.
Eina_List* eina_list_promote_list ( Eina_List *  list,
Eina_List *  move_list 
)

Moves the specified data to the head of the list.

Parameters:
[in,out]listThe given linked list.
[in]move_listThe list node to move.
Returns:
A new list handle to replace the old one, or NULL on error.

This function moves move_list to the front of list. If list is NULL, NULL is returned. If move_list is NULL, list is returned. Otherwise, a new list pointer that should be used in place of the one passed to this function is returned.

Example: 

 extern Eina_List *list;
 Eina_List *l;
 extern void *my_data;
 void *data;

 EINA_LIST_FOREACH(list, l, data)
   {
      if (data == my_data)
        {
           list = eina_list_promote_list(list, l);
           break;
        }
   }
Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
eina_list_03.c.
Eina_List* eina_list_remove ( Eina_List *  list,
const void *  data 
)

Removes the first instance of the specified data from the given list.

Parameters:
[in,out]listThe given list.
[in]dataThe specified data.
Returns:
A list pointer, or NULL on error.

This function removes the first instance of data from list. If data is not in the given list or is NULL, nothing is done and the specified list returned. If list is NULL, NULL is returned, otherwise a new list pointer that should be used in place of the one passed to this function is returned.

Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
efl_thread_6.c, eina_list_03.c, and genlist_example_05.c.
Eina_List* eina_list_remove_list ( Eina_List *  list,
Eina_List *  remove_list 
)

Removes the specified list node.

Parameters:
[in,out]listThe given linked list.
[in]remove_listThe list node which is to be removed.
Returns:
A list pointer, or NULL on error.

This function removes the list node remove_list from list and frees the list node structure remove_list. If list is NULL, this function returns NULL. If remove_list is NULL, it returns list; otherwise, a new list pointer that should be used in place of the one passed to this function.

The following code gives an example. (Notice we use EINA_LIST_FOREACH rather than EINA_LIST_FOREACH_SAFE because we stop the loop after removing the current node.)

 extern Eina_List *list;
 Eina_List *l;
 extern void *my_data;
 void *data

 EINA_LIST_FOREACH(list, l, data)
   {
      if (data == my_data)
        {
           list = eina_list_remove_list(list, l);
           break;
        }
   }
Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
eina_inlist_02.c.
Eina_List* eina_list_reverse ( Eina_List *  list)

Reverses all the elements in the list.

Parameters:
[in,out]listThe list to reverse.
Returns:
The list head after it has been reversed, or NULL on error.

This function reverses the order of all elements in list, so the last member is now first, and so on. If list is NULL, this function returns NULL.

Note:
in-place: this will change the given list, so you should now point to the new list head that is returned by this function.
Warning:
list must be a pointer to the first element of the list.
See also:
eina_list_reverse_clone()
eina_list_iterator_reversed_new()
Since :
2.3
Eina_List* eina_list_reverse_clone ( const Eina_List *  list)

Clones (copies) all the elements in the list in reverse order.

Parameters:
[in]listThe list to reverse.
Returns:
The new list that has been reversed, or NULL on error.

This function reverses the order of all elements in list, so the last member is now first, and so on. If list is NULL, this function returns NULL. This returns a copy of the given list.

Note:
copy: this will copy the list and you should then eina_list_free() when it is not required anymore.
Warning:
list must be a pointer to the first element of the list.
See also:
eina_list_reverse()
eina_list_clone()
Since :
2.3
Examples:
eina_list_03.c.
void* eina_list_search_sorted ( const Eina_List *  list,
Eina_Compare_Cb  func,
const void *  data 
)

Returns node data if it is in the sorted list.

Parameters:
[in]listThe list to search for data, must be sorted.
[in]funcA function pointer that can handle comparing the list data nodes.
[in]datareference value to search.
Returns:
The node value (node->data) if func(node->data, data) == 0, NULL if not found.

This can be used to check if some value is inside the list and get the existing instance in this case. It should be used when list is known to be sorted as it will do binary search for results.

Example: imagine user gives a string, you check if it's in the list before duplicating its contents.

Note:
O(log2(n)) average/worst case performance, for 1,000,000 elements it will do a maximum of 20 comparisons. This is much faster than the 1,000,000 comparisons made by eina_list_search_unsorted(), so depending on the number of searches and insertions, it may be worth to eina_list_sort() the list and do the searches later. As said in eina_list_search_sorted_near_list(), lists do not have O(1) access time, so walking to the correct node can be costly, consider worst case to be almost O(n) pointer dereference (list walk).
Warning:
list must be a pointer to the first element of the list.
See also:
eina_list_search_sorted_list()
eina_list_sort()
eina_list_sorted_merge()
eina_list_search_unsorted_list()
Since :
2.3
Examples:
eina_list_02.c.
Eina_List* eina_list_search_sorted_list ( const Eina_List *  list,
Eina_Compare_Cb  func,
const void *  data 
)

Returns node if data is in the sorted list.

Parameters:
[in]listThe list to search for data, must be sorted.
[in]funcA function pointer that can handle comparing the list data nodes.
[in]datareference value to search.
Returns:
The node if func(node->data, data) == 0, NULL if not found.

This can be used to check if some value is inside the list and get the container node in this case. It should be used when list is known to be sorted as it will do binary search for results.

Example: imagine user gives a string, you check if it's in the list before duplicating its contents.

Note:
O(log2(n)) average/worst case performance, for 1,000,000 elements it will do a maximum of 20 comparisons. This is much faster than the 1,000,000 comparisons made by eina_list_search_unsorted_list(), so depending on the number of searches and insertions, it may be worth to eina_list_sort() the list and do the searches later. As said in eina_list_search_sorted_near_list(), lists do not have O(1) access time, so walking to the correct node can be costly, consider worst case to be almost O(n) pointer dereference (list walk).
Warning:
list must be a pointer to the first element of the list.
See also:
eina_list_search_sorted()
eina_list_sort()
eina_list_sorted_merge()
eina_list_search_unsorted_list()
eina_list_search_sorted_near_list()
Since :
2.3
Examples:
eina_list_02.c.
Eina_List* eina_list_search_sorted_near_list ( const Eina_List *  list,
Eina_Compare_Cb  func,
const void *  data,
int *  result_cmp 
)

Returns node nearest to data from the sorted list.

Parameters:
[in]listThe list to search for data, must be sorted.
[in]funcA function pointer that can handle comparing the list data nodes.
[in]datareference value to search.
[out]result_cmpIf provided returns the result of func(node->data, data) node being the last (returned) node. If node was found (exact match), then it is 0. If returned node is smaller than requested data, it is less than 0 and if it's bigger it's greater than 0. It is the last value returned by func().
Returns:
The nearest node, NULL if not found.

This function searches for a node containing data as its data in list, if such a node exists it will be returned and result_cmp will be 0. If the data of no node in list is equal to data, the node with the nearest value to that will be returned and result_cmp will be the return value of func with data and the returned node's data as arguments.

This function is useful for inserting an element in the list only in case it isn't already present in the list, the naive way of doing this would be: 

 void *ptr = eina_list_data_find(list, "my data");
 if (!ptr)
   eina_list_sorted_insert(list, "my data");

However this has the downside of walking through the list twice, once to check if the data is already present and another to insert the element in the correct position. This can be done more efficiently: 

 int cmp_result;
 l = eina_list_search_sorted_near_list(list, cmp_func, "my data",
                                       &cmp_result);
 if (cmp_result > 0)
   list = eina_list_prepend_relative_list(list, "my data", l);
 else if (cmp_result < 0)
   list = eina_list_append_relative_list(list, "my data", l);

If cmp_result is 0 the element is already in the list and we need not insert it, if cmp_result is greater than zero "my @a data" needs to come after l (the nearest node present), if less than zero before.

Note:
O(log2(n)) average/worst case performance, for 1,000,000 elements it will do a maximum of 20 comparisons. This is much faster than the 1,000,000 comparisons made naively walking the list from head to tail, so depending on the number of searches and insertions, it may be worth to eina_list_sort() the list and do the searches later. As lists do not have O(1) access time, walking to the correct node can be costly, consider worst case to be almost O(n) pointer dereference (list walk).
Warning:
list must be a pointer to the first element of the list.
See also:
eina_list_search_sorted_list()
eina_list_sort()
eina_list_sorted_merge()
Since :
2.3
Examples:
eina_list_02.c.
void* eina_list_search_unsorted ( const Eina_List *  list,
Eina_Compare_Cb  func,
const void *  data 
)

Returns node data if it is in the unsorted list.

Parameters:
[in]listThe list to search for data, may be unsorted.
[in]funcA function pointer that can handle comparing the list data nodes.
[in]datareference value to search.
Returns:
The node value (node->data) if func(node->data, data) == 0, NULL if not found.

This can be used to check if some value is inside the list and get the existing instance in this case.

Example: imagine user gives a string, you check if it's in the list before duplicating its contents.

Note:
this is expensive and may walk the whole list, it's order-N, that is, for 1,000,000 elements list it may walk and compare 1,000,000 nodes.
Warning:
list must be a pointer to the first element of the list.
See also:
eina_list_search_sorted()
eina_list_search_unsorted_list()
Since :
2.3
Examples:
eina_list_02.c.
Eina_List* eina_list_search_unsorted_list ( const Eina_List *  list,
Eina_Compare_Cb  func,
const void *  data 
)

Returns node if data is in the unsorted list.

Parameters:
[in]listThe list to search for data, may be unsorted.
[in]funcA function pointer that can handle comparing the list data nodes.
[in]datareference value to search.
Returns:
The node if func(node->data, data) == 0, NULL if not found.

This can be used to check if some value is inside the list and get the container node in this case.

Example: imagine user gives a string, you check if it's in the list before duplicating its contents.

Note:
this is expensive and may walk the whole list, it's order-N, that is for 1,000,000 elements list it may walk and compare 1,000,000 nodes.
Warning:
list must be a pointer to the first element of the list.
See also:
eina_list_search_sorted_list()
eina_list_search_unsorted()
Since :
2.3
Examples:
eina_list_02.c.
Eina_List* eina_list_shuffle ( Eina_List *  list,
Eina_Random_Cb  func 
)

Shuffles list.

Parameters:
[in]listThe list handle to shuffle.
[in]funcA function pointer that can return an int between 2 inclusive values
Returns:
The new head of list.

This function shuffles list. func is used to generate random list indexes within the range of unshuffled list items. If func is NULL, rand is used.

Note:
in-place: This will change the given list, so you should now point to the new list head that is returned by this function.
Since (EFL) :
1.8
Warning:
list must be a pointer to the first element of the list.
Since :
3.0
Eina_List* eina_list_sort ( Eina_List *  list,
unsigned int  limit,
Eina_Compare_Cb  func 
)

Sorts a list according to the ordering func will return.

Parameters:
[in]listThe list handle to sort.
[in]limitThe maximum number of list elements to sort.
[in]funcA function pointer that can handle comparing the list data nodes.
Returns:
The new head of list.

This function sorts list. If limit is 0 or greater than the number of elements in list, all the elements are sorted. func is used to compare two elements of list. If func is NULL, this function returns list.

Note:
in-place: this will change the given list, so you should now point to the new list head that is returned by this function.
Worst case is O(n * log2(n)) comparisons (calls to func()). That means that for 1,000,000 list sort will do 20,000,000 comparisons.

Example: 

 int
 sort_cb(const void *d1, const void *d2)
 {
    const char *txt = d1;
    const char *txt2 = d2;

    if(!txt) return(1);
    if(!txt2) return(-1);

    return(strcmp(txt, txt2));
 }
 extern Eina_List *list;

 list = eina_list_sort(list, eina_list_count(list), sort_cb);
Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
eina_list_02.c.
Eina_List* eina_list_sorted_insert ( Eina_List *  list,
Eina_Compare_Cb  func,
const void *  data 
)

Inserts a new node into a sorted list.

Parameters:
[in,out]listThe given linked list, must be sorted.
[in]funcThe function called for the sort.
[in]dataThe data to be inserted in sorted order.
Returns:
A list pointer, or NULL on error.

This function inserts values into a linked list assuming it was sorted and the result will be sorted. If list is NULL, a new list is returned. On success, a new list pointer that should be used in place of the one given to this function is returned. Otherwise, the old pointer is returned.

Note:
O(log2(n)) comparisons (calls to func) average/worst case performance as it uses eina_list_search_sorted_near_list() and thus is bounded to that. As said in eina_list_search_sorted_near_list(), lists do not have O(1) access time, so walking to the correct node can be costly, consider worst case to be almost O(n) pointer dereference (list walk).
Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
eina_list_02.c.
Eina_List* eina_list_sorted_merge ( Eina_List *  left,
Eina_List *  right,
Eina_Compare_Cb  func 
)

Merges two sorted list according to the ordering func will return.

Parameters:
[in]leftFirst list to merge.
[in]rightSecond list to merge.
[in]funcA function pointer that can handle comparing the list data nodes.
Returns:
A new sorted list.

This function compares the head of left and right, and choose the smallest one to be head of the returned list. It will continue this process for all entry of both list.

Both left and right lists are not valid anymore after the merge and should not be used. If func is NULL, it will return NULL.

Example: 

 int
 sort_cb(void *d1, void *d2)
 {
    const char *txt = NULL;
    const char *txt2 = NULL;

    if(!d1) return(1);
    if(!d2) return(-1);

    return(strcmp((const char*)d1, (const char*)d2));
 }
 extern Eina_List *sorted1;
 extern Eina_List *sorted2;

 list = eina_list_sorted_merge(sorted1, sorted2, sort_cb);
Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
eina_list_02.c.
Eina_List* eina_list_split_list ( Eina_List *  list,
Eina_List *  relative,
Eina_List **  right 
)

Splits a list into 2 lists.

Parameters:
[in]listList to split.
[in]relativeThe list will be split after relative.
[out]rightThe head of the new right list.
Returns:
The new left list

This function splits list into two lists ( left and right ) after the node relative. Relative will become the last node of the left list. If list or right are NULL list is returns. If relative is NULL right is set to list and NULL is returns. If relative is the last node of list list is returns and right is set to NULL.

list does not exist anymore after the split.

Warning:
list must be a pointer to the first element of the list.
Since :
2.3
Examples:
eina_list_02.c.