#ifndef lkf_h
#define lkf_h
struct lkf_node {
struct lkf_node* next;
};
struct lkf_list {
struct lkf_node root;
struct lkf_node** tail;
};
#define LKF_INIT(name) {.root = {NULL}, .tail = &(name.root.next)}
#define LKF_LIST(name) \
struct lkf_list name = LKF_INIT(name)
#define INIT_LKF(name) \
do { \
name->root.next = NULL; \
name->tail = &(name->root.next); \
} while (0)
static inline void lkf_node_put(struct lkf_list* list, struct lkf_node* node)
{
node->next = NULL;
struct lkf_node** ptr = __sync_lock_test_and_set(&(list->tail), &(node->next));
*ptr = node;
}
static inline struct lkf_node* lkf_node_get_one(struct lkf_list* list)
{
struct lkf_node* head = __sync_lock_test_and_set(&(list->root.next), NULL);
if (head == NULL) {
return NULL;
}
struct lkf_node* next = head->next;
if (next != NULL) {
list->root.next = next;
head->next = head;
return head;
}
int b = __sync_bool_compare_and_swap(&(list->tail), &(head->next), &(list->root.next));
if (b) {
head->next = head;
return head;
}
list->root.next = head;
return NULL;
}
static inline struct lkf_node* lkf_node_get(struct lkf_list* list)
{
struct lkf_node* ptr = __sync_lock_test_and_set(&(list->root.next), NULL);
if (ptr == NULL) {
return NULL;
}
struct lkf_node** last = __sync_lock_test_and_set(&(list->tail), &(list->root.next));
*last = ptr;
return *last;
}
static inline struct lkf_node* lkf_node_next(struct lkf_node* node)
{
struct lkf_node* ptr = node->next;
if (ptr == NULL || ptr->next == NULL) {
return NULL;
}
if (ptr == node) {
return ptr;
}
node->next = ptr->next;
ptr->next = NULL;
return ptr;
}
#endif