libwget-list - Circular doubly linked list

       Generated automatically by Doxygen for wget2 from the source code.

wget2                                             Version 2.2.0                                  libwget-list(3)

       Circular doubly linked lists provide fast insertion, removal and iteration in either direction.

       Each element has pointers to the next and the previous element.
        Iteration can be done by calling the wget_list_browse() function, so the list structure doesn't need to
       be exposed.

       This datatype is used by the Wget2 tool to implement the job queue (append and remove).

       See wget_list_append() for an example on how to use lists.

void*wget_list_append(wget_list**list,constvoid*data,size_tsize)Parameterslist Pointer to Pointer to a circular doubly linked list
           data Pointer to data to be inserted
           size Size of data in bytes

       Returns
           Pointer to the new element or NULL if memory allocation failed

       Append an element to the end of the list.
        size bytes at data will be copied and appended to the list.

       A pointer to the new element will be returned.

       Note
           The returned pointer must be freed by wget_list_remove() or implicitly by wget_list_free().

       Example:

       wget_list *list = NULL;
       struct mystruct mydata1 = { .x = 1, .y = 25 };
       struct mystruct mydata2 = { .x = 5, .y = 99 };
       struct mystruct *data;

       wget_list_append(&list, &mydata1, sizeof(mydata1)); // append mydata1 to list
       wget_list_append(&list, &mydata2, sizeof(mydata2)); // append mydata2 to list

       data = wget_list_getfirst(list);
       printf("data=(%d,%d)\n", data->x, data->y); // prints 'data=(1,25)'

       wget_list_remove(&list, data);

       data = wget_list_getfirst(list);
       printf("data=(%d,%d)\n", data->x, data->y); // prints 'data=(5,99)'

       wget_list_free(&list);

   void*wget_list_prepend(wget_list**list,constvoid*data,size_tsize)Parameterslist Pointer to Pointer to a circular doubly linked list
           data Pointer to data to be inserted
           size Size of data in bytes

       Returns
           Pointer to the new element or NULL if memory allocation failed

       Insert an entry at the beginning of the list. size bytes at data will be copied and prepended to the
       list.

       A pointer to the new element will be returned. It must be freed by wget_list_remove() or implicitly by
       wget_list_free().

   voidwget_list_remove(wget_list**list,void*elem)Parameterslist Pointer to Pointer to a circular doubly linked list
           elem Pointer to a list element returned by wget_list_append() or wget_list_prepend()

       Remove an element from the list.

   void*wget_list_getfirst(constwget_list*list)Parameterslist Pointer to a circular doubly linked list

       Returns
           Pointer to the first element of the list or NULL if the list is empty

       Get the first element of a list.

   void*wget_list_getlast(constwget_list*list)Parameterslist Pointer to a circular doubly linked list

       Returns
           Pointer to the last element of the list or NULL if the list is empty

       Get the last element of a list.

   void*wget_list_getnext(constvoid*elem)Parameterselem Pointer to an element of a linked list

       Returns
           Pointer to the next element of the list or NULL if the list is empty

       Get the next element of a list.

   intwget_list_browse(constwget_list*list,wget_list_browse_fn*browse,void*context)Parameterslist Pointer to a circular doubly linked list
           browse Pointer to callback function which is called for every element in the list. If the callback
           functions returns a value not equal to zero, browsing is stopped and this value will be returned by
           wget_list_browse.
           context The context handle that will be passed to the callback function

       Returns
           The return value of the last call to the browse function or -1 if list is NULL (empty)

       Iterate through all entries of the list and call the function browse for each.

       // assume that list contains C strings.
       wget_list *list = NULL;

       static int print_elem(void *context, const char *elem)
       {
          printf("%s\n",elem);
          return 0;
       }

       void dump(WGET_LIST *list)
       {
          wget_list_browse(list, (wget_list_browse_t)print_elem, NULL);
       }

   voidwget_list_free(wget_list**list)Parameterslist Pointer to Pointer to a circular doubly linked list

       Freeing the list and it's entry.

       libwget-list - Circular doubly linked list

DataStructures
       struct wget_list_stTypedefs
       typedef struct wget_list_stwget_listFunctions
       void * wget_list_append (wget_list **list, const void *data, size_t size)
       void * wget_list_prepend (wget_list **list, const void *data, size_t size)
       void wget_list_remove (wget_list **list, void *elem)
       void * wget_list_getfirst (const wget_list *list)
       void * wget_list_getlast (const wget_list *list)
       void * wget_list_getnext (const void *elem)
       int wget_list_browse (const wget_list *list, wget_list_browse_fn *browse, void *context)
       void wget_list_free (wget_list **list)

typedefstructwget_list_stwget_list
       Type for double linked lists and list entries.