Tizen Native API  4.0

Eina_Clist is a compact (inline) list implementation.

Elements of this list are members of the structs stored in the list.

Advantages over Eina_List and Eina_Inlist :

  • Uses less memory (two machine words per item).
  • Allows removing items without knowing which list they're in while using O(1) time.
  • Doesn't need to keep updating the head pointer as the list is changed.

Disadvantages:

  • O(N) time to calculate the list length.
  • Requires one list entry in a struct per list (i.e. it's an inlist).
  • Requires a head/tail pointer.
  • Needs to know the list head when moving to the next or previous pointer.
Note:
There's no NULL at the end of the list, the last item points to the head.
List heads must be initialized with EINA_CLIST_INIT or by calling eina_clist_element_init.

Define a list as follows:

   struct gadget
   {
       struct Eina_Clist  entry;   <-- doesn't have to be the first item in the struct
       int                a, b;
   };

   static Eina_Clist global_gadgets = EINA_CLIST_INIT( global_gadgets );

or

   struct some_global_thing
   {
       Eina_Clist gadgets;
   };

   eina_clist_init( &some_global_thing->gadgets );

Manipulate it like this:

   eina_clist_add_head( &global_gadgets, &new_gadget->entry );
   eina_clist_remove( &new_gadget->entry );
   eina_clist_add_after( &some_random_gadget->entry, &new_gadget->entry );

And to iterate over it:

   struct gadget *gadget;
   EINA_CLIST_FOR_EACH_ENTRY( gadget, &global_gadgets, struct gadget, entry )
   {
       ...
   }

Functions

static void eina_clist_add_after (Eina_Clist *elem, Eina_Clist *to_add)
 Adds an element after the specified one.
static void eina_clist_add_before (Eina_Clist *elem, Eina_Clist *to_add)
 Adds an element before the specified one.
static void eina_clist_add_head (Eina_Clist *list, Eina_Clist *elem)
 Adds an element to the head of the list.
static void eina_clist_add_tail (Eina_Clist *list, Eina_Clist *elem)
 Adds an element at the tail of the list.
static void eina_clist_element_init (Eina_Clist *elem)
 Inits an (unlinked) element.
static int eina_clist_element_is_linked (Eina_Clist *elem)
 Checks whether an element is in a list.
static void eina_clist_remove (Eina_Clist *elem)
 Removes an element from its list.
static Eina_Clisteina_clist_next (const Eina_Clist *list, const Eina_Clist *elem)
 Gets the next element.
static Eina_Clisteina_clist_prev (const Eina_Clist *list, const Eina_Clist *elem)
 Gets the previous element.
static Eina_Clisteina_clist_head (const Eina_Clist *list)
 Gets the first element.
static Eina_Clisteina_clist_tail (const Eina_Clist *list)
 Gets the last element.
static int eina_clist_empty (const Eina_Clist *list)
 Checks whether a list is empty.
static void eina_clist_init (Eina_Clist *list)
 Initializes a list.
static unsigned int eina_clist_count (const Eina_Clist *list)
 Counts the elements of a list.
static void eina_clist_move_tail (Eina_Clist *dst, Eina_Clist *src)
 Moves all elements from src to the tail of dst.
static void eina_clist_move_head (Eina_Clist *dst, Eina_Clist *src)
 Moves all elements from src to the head of dst.

Typedefs

typedef struct _Eina_Clist Eina_Clist
 Type for _Eina_Clist structure containing the list head and the list entry.

Defines

#define EINA_CLIST_FOR_EACH(cursor, list)   for ((cursor) = (list)->next; (cursor) != (list); (cursor) = (cursor)->next)
 Iterates through the list.
#define EINA_CLIST_FOR_EACH_SAFE(cursor, cursor2, list)
 Iterates through the list, with safety against removal.
#define EINA_CLIST_FOR_EACH_ENTRY(elem, list, type, field)
 Iterates through the list using a list entry.
#define EINA_CLIST_FOR_EACH_ENTRY_SAFE(cursor, cursor2, list, type, field)
 Iterates through the list using a list entry, with safety against removal.
#define EINA_CLIST_FOR_EACH_REV(cursor, list)   for ((cursor) = (list)->prev; (cursor) != (list); (cursor) = (cursor)->prev)
 Iterates through the list in the reverse order.
#define EINA_CLIST_FOR_EACH_SAFE_REV(cursor, cursor2, list)
 Iterates through the list in the reverse order, with safety against removal.
#define EINA_CLIST_FOR_EACH_ENTRY_REV(elem, list, type, field)
 Iterates through the list in the reverse order using a list entry.
#define EINA_CLIST_FOR_EACH_ENTRY_SAFE_REV(cursor, cursor2, list, type, field)
 Iterates through the list in the reverse order using a list entry, with safety against removal.
#define EINA_CLIST_INIT(list)   { &(list), &(list) }
 Macros for statically initialized lists.
#define EINA_CLIST_ENTRY(elem, type, field)   ((type *)((char *)(elem) - (uintptr_t)(&((type *)0)->field)))
 Gets a pointer to the object containing the list element.

Define Documentation

#define EINA_CLIST_ENTRY (   elem,
  type,
  field 
)    ((type *)((char *)(elem) - (uintptr_t)(&((type *)0)->field)))

Gets a pointer to the object containing the list element.

Parameters:
elemThe element to be used
typeThe type of the element
fieldThe field of the element
#define EINA_CLIST_FOR_EACH (   cursor,
  list 
)    for ((cursor) = (list)->next; (cursor) != (list); (cursor) = (cursor)->next)

Iterates through the list.

Parameters:
cursorThe pointer to be used during the interaction
listThe list to be interacted with
#define EINA_CLIST_FOR_EACH_ENTRY (   elem,
  list,
  type,
  field 
)
Value:
for ((elem) = EINA_CLIST_ENTRY((list)->next, type, field); \
         &(elem)->field != (list); \
         (elem) = EINA_CLIST_ENTRY((elem)->field.next, type, field))

Iterates through the list using a list entry.

Parameters:
elemThe element to be used
listThe list to be iterated
typeThe type of the list
fieldThe field of the element
#define EINA_CLIST_FOR_EACH_ENTRY_REV (   elem,
  list,
  type,
  field 
)
Value:
for ((elem) = EINA_CLIST_ENTRY((list)->prev, type, field); \
         &(elem)->field != (list); \
         (elem) = EINA_CLIST_ENTRY((elem)->field.prev, type, field))

Iterates through the list in the reverse order using a list entry.

Parameters:
elemThe element to be used
listThe list to be iterated
typeThe type of the list
fieldThe field of the element
#define EINA_CLIST_FOR_EACH_ENTRY_SAFE (   cursor,
  cursor2,
  list,
  type,
  field 
)
Value:
for ((cursor) = EINA_CLIST_ENTRY((list)->next, type, field), \
         (cursor2) = EINA_CLIST_ENTRY((cursor)->field.next, type, field); \
         &(cursor)->field != (list); \
         (cursor) = (cursor2), \
         (cursor2) = EINA_CLIST_ENTRY((cursor)->field.next, type, field))

Iterates through the list using a list entry, with safety against removal.

Parameters:
cursorThe pointer to be used during the interaction
cursor2The auxiliary pointer to be used during the interaction
listThe list to be interacted with
typeThe type of the list
fieldThe field of the element
#define EINA_CLIST_FOR_EACH_ENTRY_SAFE_REV (   cursor,
  cursor2,
  list,
  type,
  field 
)
Value:
for ((cursor) = EINA_CLIST_ENTRY((list)->prev, type, field), \
         (cursor2) = EINA_CLIST_ENTRY((cursor)->field.prev, type, field); \
         &(cursor)->field != (list); \
         (cursor) = (cursor2), \
         (cursor2) = EINA_CLIST_ENTRY((cursor)->field.prev, type, field))

Iterates through the list in the reverse order using a list entry, with safety against removal.

Parameters:
cursorThe pointer to be used during the interaction
cursor2The auxiliary pointer to be used during the interaction
listThe list to be interacted with
typeThe type of the list
fieldThe field of the element
#define EINA_CLIST_FOR_EACH_REV (   cursor,
  list 
)    for ((cursor) = (list)->prev; (cursor) != (list); (cursor) = (cursor)->prev)

Iterates through the list in the reverse order.

Parameters:
cursorThe pointer to be used during the interaction
listThe list to be interacted with
#define EINA_CLIST_FOR_EACH_SAFE (   cursor,
  cursor2,
  list 
)
Value:
for ((cursor) = (list)->next, (cursor2) = (cursor)->next; \
         (cursor) != (list); \
         (cursor) = (cursor2), (cursor2) = (cursor)->next)

Iterates through the list, with safety against removal.

Parameters:
cursorThe pointer to be used during the interaction
cursor2The auxiliary pointer to be used during the interaction
listThe list to be interacted with
#define EINA_CLIST_FOR_EACH_SAFE_REV (   cursor,
  cursor2,
  list 
)
Value:
for ((cursor) = (list)->prev, (cursor2) = (cursor)->prev; \
         (cursor) != (list); \
         (cursor) = (cursor2), (cursor2) = (cursor)->prev)

Iterates through the list in the reverse order, with safety against removal.

Parameters:
cursorThe pointer to be used during the interaction
cursor2The auxiliary pointer to be used during the interaction
listThe list to be interacted with
#define EINA_CLIST_INIT (   list)    { &(list), &(list) }

Macros for statically initialized lists.

Parameters:
listThe list to be used

Typedef Documentation

Type for _Eina_Clist structure containing the list head and the list entry.

Since (EFL) :
1.1.0

Function Documentation

static void eina_clist_add_after ( Eina_Clist elem,
Eina_Clist to_add 
) [static]

Adds an element after the specified one.

Parameters:
[in]elemAn element in the list
[in]to_addThe element to add to the list
Precondition:
The list head must be initialized once before adding anything.
The element is not in any list.
Note:
There is no need to initialize an element before adding it to the list.
Since (EFL) :
1.1.0
static void eina_clist_add_before ( Eina_Clist elem,
Eina_Clist to_add 
) [static]

Adds an element before the specified one.

Parameters:
[in]elemAn element in the list
[in]to_addThe element to add to the list
Precondition:
The list head must be initialized once before adding anything.
The element is not in any list.
Note:
There is no need to initialize an element before adding it to the list.
Since (EFL) :
1.1.0
static void eina_clist_add_head ( Eina_Clist list,
Eina_Clist elem 
) [static]

Adds an element to the head of the list.

Parameters:
[in]listThe list
[in]elemAn element
Precondition:
The list head must be initialized once before adding anything.
The element is not in any list.
Note:
There is no need to initialize an element before adding it to the list.
Since (EFL) :
1.1.0
static void eina_clist_add_tail ( Eina_Clist list,
Eina_Clist elem 
) [static]

Adds an element at the tail of the list.

Parameters:
[in]listThe list
[in]elemAn element
Precondition:
The list head must be initialized once before adding anything.
The element is not in any list.
Note:
There is no need to initialize an element before adding it to the list.
Since (EFL) :
1.1.0
static unsigned int eina_clist_count ( const Eina_Clist list) [static]

Counts the elements of a list.

Parameters:
[in]listThe list
Returns:
The number of items in the list
Since (EFL) :
1.1.0
static void eina_clist_element_init ( Eina_Clist elem) [static]

Inits an (unlinked) element.

This function is called on elements that have not been added to the list so that eina_clist_element_init() works correctly.

Parameters:
[in]elemAn element
Precondition:
The element is not in any list.
Postcondition:
The element is marked as not being in any list.
Note:
It is not necessary to call this before adding an element to this list.
Since (EFL) :
1.1.0
static int eina_clist_element_is_linked ( Eina_Clist elem) [static]

Checks whether an element is in a list.

Parameters:
[in]elemAn element
Returns:
TRUE if the element is in a list, else FALSE.
Precondition:
Either eina_clist_element_init() has been called on elem, or it has been added to a list or removed from a list.
Since (EFL) :
1.1.0
static int eina_clist_empty ( const Eina_Clist list) [static]

Checks whether a list is empty.

Parameters:
[in]listThe list
Returns:
A non-zero value if list is empty, otherwise zero if it is not
Since (EFL) :
1.1.0
static Eina_Clist* eina_clist_head ( const Eina_Clist list) [static]

Gets the first element.

Parameters:
[in]listThe list
Returns:
The first element in list, otherwise NULL if list is empty
Since (EFL) :
1.1.0
static void eina_clist_init ( Eina_Clist list) [static]

Initializes a list.

Parameters:
[in]listThe list
Precondition:
The list is uninitialized
Postcondition:
The list contains no items
Note:
Don't call this function on a list with items
This function must be called. Don't try to initialize the list by zeroing out the list head.
Since (EFL) :
1.1.0
static void eina_clist_move_head ( Eina_Clist dst,
Eina_Clist src 
) [static]

Moves all elements from src to the head of dst.

Parameters:
[in]dstThe list to be prepended to
[in]srcThe list to prepend
Postcondition:
src is initialized, but is empty after this operation.
Since (EFL) :
1.1.0
static void eina_clist_move_tail ( Eina_Clist dst,
Eina_Clist src 
) [static]

Moves all elements from src to the tail of dst.

Parameters:
[in]dstThe list to be appended to
[in]srcThe list to append
Postcondition:
src is initialized, but is empty after this operation.
Since (EFL) :
1.1.0
static Eina_Clist* eina_clist_next ( const Eina_Clist list,
const Eina_Clist elem 
) [static]

Gets the next element.

Parameters:
[in]listThe list
[in]elemAn element
Returns:
The element after elem in list, otherwise NULL if elem is last in list
Precondition:
elem is in list.
Since (EFL) :
1.1.0
static Eina_Clist* eina_clist_prev ( const Eina_Clist list,
const Eina_Clist elem 
) [static]

Gets the previous element.

Parameters:
[in]listThe list
[in]elemAn element
Returns:
The element before elem, otherwise NULL if elem is first in list
Since (EFL) :
1.1.0
static void eina_clist_remove ( Eina_Clist elem) [static]

Removes an element from its list.

Parameters:
[in]elemAn element
Precondition:
The element is already in a list.
Postcondition:
The element is marked as not being in any list.
Since (EFL) :
1.1.0
static Eina_Clist* eina_clist_tail ( const Eina_Clist list) [static]

Gets the last element.

Parameters:
[in]listThe list
Returns:
The last element in list, otherwise NULL if list is empty
Since (EFL) :
1.1.0