#include "pth_p.h"
intern void pth_ring_init(pth_ring_t *r)
{
if (r == NULL)
return;
r->r_hook = NULL;
r->r_nodes = 0;
return;
}
#if cpp
#define pth_ring_elements(r) \
((r) == NULL ? (-1) : (r)->r_nodes)
#endif
#if cpp
#define pth_ring_first(r) \
((r) == NULL ? NULL : (r)->r_hook)
#endif
#if cpp
#define pth_ring_last(r) \
((r) == NULL ? NULL : ((r)->r_hook == NULL ? NULL : (r)->r_hook->rn_prev))
#endif
#if cpp
#define pth_ring_next(r, rn) \
(((r) == NULL || (rn) == NULL) ? NULL : ((rn)->rn_next == (r)->r_hook ? NULL : (rn)->rn_next))
#endif
#if cpp
#define pth_ring_prev(r, rn) \
(((r) == NULL || (rn) == NULL) ? NULL : ((rn)->rn_prev == (r)->r_hook->rn_prev ? NULL : (rn)->rn_prev))
#endif
#if cpp
#define pth_ring_insert(r, rn) \
pth_ring_append((r), (rn))
#endif
intern void pth_ring_insert_after(pth_ring_t *r, pth_ringnode_t *rn1, pth_ringnode_t *rn2)
{
if (r == NULL || rn1 == NULL || rn2 == NULL)
return;
rn2->rn_prev = rn1;
rn2->rn_next = rn1->rn_next;
rn2->rn_prev->rn_next = rn2;
rn2->rn_next->rn_prev = rn2;
r->r_nodes++;
return;
}
intern void pth_ring_insert_before(pth_ring_t *r, pth_ringnode_t *rn1, pth_ringnode_t *rn2)
{
if (r == NULL || rn1 == NULL || rn2 == NULL)
return;
rn2->rn_next = rn1;
rn2->rn_prev = rn1->rn_prev;
rn2->rn_prev->rn_next = rn2;
rn2->rn_next->rn_prev = rn2;
r->r_nodes++;
return;
}
intern void pth_ring_delete(pth_ring_t *r, pth_ringnode_t *rn)
{
if (r == NULL || rn == NULL)
return;
if (r->r_hook == rn && rn->rn_prev == rn && rn->rn_next == rn)
r->r_hook = NULL;
else {
if (r->r_hook == rn)
r->r_hook = rn->rn_next;
rn->rn_prev->rn_next = rn->rn_next;
rn->rn_next->rn_prev = rn->rn_prev;
}
r->r_nodes--;
return;
}
intern void pth_ring_prepend(pth_ring_t *r, pth_ringnode_t *rn)
{
if (r == NULL || rn == NULL)
return;
if (r->r_hook == NULL) {
r->r_hook = rn;
rn->rn_next = rn;
rn->rn_prev = rn;
}
else {
rn->rn_next = r->r_hook;
rn->rn_prev = r->r_hook->rn_prev;
rn->rn_next->rn_prev = rn;
rn->rn_prev->rn_next = rn;
r->r_hook = rn;
}
r->r_nodes++;
return;
}
intern void pth_ring_append(pth_ring_t *r, pth_ringnode_t *rn)
{
if (r == NULL || rn == NULL)
return;
if (r->r_hook == NULL) {
r->r_hook = rn;
rn->rn_next = rn;
rn->rn_prev = rn;
}
else {
rn->rn_next = r->r_hook;
rn->rn_prev = r->r_hook->rn_prev;
rn->rn_next->rn_prev = rn;
rn->rn_prev->rn_next = rn;
}
r->r_nodes++;
return;
}
#if cpp
#define pth_ring_push(r, rn) \
pth_ring_prepend((r), (rn))
#endif
intern pth_ringnode_t *pth_ring_pop(pth_ring_t *r)
{
pth_ringnode_t *rn;
rn = pth_ring_first(r);
if (rn != NULL)
pth_ring_delete(r, rn);
return rn;
}
intern int pth_ring_favorite(pth_ring_t *r, pth_ringnode_t *rn)
{
if (r == NULL)
return FALSE;
if (r->r_hook == NULL)
return FALSE;
if (r->r_hook == rn)
return TRUE;
pth_ring_delete(r, rn);
pth_ring_prepend(r, rn);
return TRUE;
}
#if cpp
#define pth_ring_enqueue(r, rn) \
pth_ring_prepend((r), (rn))
#endif
intern pth_ringnode_t *pth_ring_dequeue(pth_ring_t *r)
{
pth_ringnode_t *rn;
rn = pth_ring_last(r);
if (rn != NULL)
pth_ring_delete(r, rn);
return rn;
}
intern int pth_ring_contains(pth_ring_t *r, pth_ringnode_t *rns)
{
pth_ringnode_t *rn;
int rc;
if (r == NULL || rns == NULL)
return_errno(FALSE, EINVAL);
rc = FALSE;
rn = r->r_hook;
if (rn != NULL) {
do {
if (rn == rns) {
rc = TRUE;
break;
}
rn = rn->rn_next;
} while (rn != r->r_hook);
}
return rc;
}