/* List object
*
* The list object is a generic container for storing collections
* of things in order.
*/
#ifndef HTLIST_H
#define HTLIST_H
#ifndef HTUTILS_H
#include <HTUtils.h>
#endif
#ifdef __cplusplus
extern "C" {
#endif
typedef struct _HTList HTList;
struct _HTList {
void *object;
HTList *next;
};
/* Fast macro to traverse a list. Call it first with copy of the list
* header. It returns the first object and increments the passed list
* pointer. Call it with the same variable until it returns NULL.
*/
#define HTList_nextObject(me) \
((me) && ((me) = (me)->next) ? (me)->object : NULL)
/* Macro to find object pointed to by the head (returns NULL
* if list is empty, OR if it doesn't exist - Yuk!)
*/
#define HTList_lastObject(me) \
((me) && (me)->next ? (me)->next->object : NULL)
/* Macro to check if a list is empty (or doesn't exist - Yuk!)
*/
#define HTList_isEmpty(me) ((me) ? ((me)->next == NULL) : YES)
/* Create list.
*/
extern HTList *HTList_new(void);
/* Delete list.
*/
extern void HTList_delete(HTList *me);
/* Reverse a list.
*/
extern HTList *HTList_reverse(HTList *start);
/* Append two lists, making second list empty.
*/
extern HTList *HTList_appendList(HTList *start,
HTList *tail);
/* Add object to START of list (so it is pointed to by the head).
*/
extern void HTList_addObject(HTList *me,
void *newObject);
/* Append object to END of list (furthest from the head).
*/
extern void HTList_appendObject(HTList *me,
void *newObject);
/* Insert an object into the list at a specified position.
* If position is 0, this places the object at the head of the list
* and is equivalent to HTList_addObject().
*/
extern void HTList_insertObjectAt(HTList *me,
void *newObject,
int pos);
/* Remove specified object from list.
*/
extern BOOL HTList_removeObject(HTList *me,
void *oldObject);
/* Remove object at a given position in the list, where 0 is the
* object pointed to by the head (returns a pointer to the element
* (->object) for the object, and NULL if the list is empty, or
* if it doesn't exist - Yuk!).
*/
extern void *HTList_removeObjectAt(HTList *me,
int position);
/* Remove object from START of list (the Last one inserted
* via HTList_addObject(), and pointed to by the head).
*/
extern void *HTList_removeLastObject(HTList *me);
/* Remove object from END of list (the First one inserted
* via HTList_addObject(), and furthest from the head).
*/
extern void *HTList_removeFirstObject(HTList *me);
/* Determine total number of objects in the list,
* not counting the head.
*/
extern int HTList_count(HTList *me);
/* Determine position of an object in the list (a value of 0
* means it is pointed to by the head; returns -1 if not found).
*/
extern int HTList_indexOf(HTList *me,
void *object);
/* Return pointer to the object at a specified position in the list,
* where 0 is the object pointed to by the head (returns NULL if
* the list is empty, or if it doesn't exist - Yuk!).
*/
extern void *HTList_objectAt(HTList *me,
int position);
/* Link object to START of list (so it is pointed to by the head).
*
* Unlike HTList_addObject(), it does not malloc memory for HTList entry,
* it use already allocated memory which should not be free'd by any
* list operations (optimization).
*/
extern void HTList_linkObject(HTList *me,
void *newObject,
HTList *newNode);
/* Unlink object from START of list (the Last one inserted
* via HTList_linkObject(), and pointed to by the head).
* It does not free memory.
*/
extern void *HTList_unlinkLastObject(HTList *me);
/* Unlink specified object from list.
* It does not free memory.
*/
extern BOOL HTList_unlinkObject(HTList *me,
void *oldObject);
#ifdef __cplusplus
}
#endif
#endif /* HTLIST_H */