- Implemented deletions

- Added rbl_foreach() function
This commit is contained in:
Guus Sliepen 2000-11-18 23:21:01 +00:00
parent 00e5d57262
commit 880cd6f1a9
2 changed files with 169 additions and 14 deletions

162
lib/rbl.c
View file

@ -17,7 +17,7 @@
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
$Id: rbl.c,v 1.1.2.2 2000/11/18 18:14:57 guus Exp $
$Id: rbl.c,v 1.1.2.3 2000/11/18 23:21:00 guus Exp $
*/
@ -34,7 +34,7 @@ void free_rbl(rbl_t *rbl)
}
/* Allocate a new rbltree header */
rbltree_t *new_rbltree(rbl_compare_t *compare, rbl_delete_t *delete)
rbltree_t *new_rbltree(rbl_compare_t *compare, rbl_action_t *delete)
{
rbltree_t *tree;
@ -60,7 +60,7 @@ rbl_t rbl_search_closest(rbltree_t *tree, void *data)
rbl_t *rbl, *next;
int result;
next = rbl = tree->head;
next = rbl = tree->top;
while(next)
{
@ -85,7 +85,7 @@ rbl_t rbl_search(rbltree_t *tree, void *data)
rbl_t *rbl, *next;
int result;
next = rbl = tree->head;
next = rbl = tree->top;
while(next)
{
@ -121,7 +121,7 @@ void rbl_left_rotate(rbl_t *x)
y->parent = x->parent;
if(!x->parent)
x->tree->head = y;
x->tree->top = y;
else
if(x == x->parent->left)
x->parent->left = y;
@ -145,7 +145,7 @@ void rbl_right_rotate(rbl_t *y)
x->parent = y->parent;
if(!y->parent)
y->tree->head = x;
y->tree->top = x;
else
if(y == y->parent->right)
y->parent->right = x;
@ -164,7 +164,7 @@ rbl_t rbl_insert_rbl(rbltree_t *tree, rbl_t *rbl)
/* Binary tree and linked list insert */
if(tree->head)
if(tree->top)
{
closest = rbl_search_closest(tree, rbl->data);
result = tree->compare(rbl->data, data);
@ -188,7 +188,7 @@ rbl_t rbl_insert_rbl(rbltree_t *tree, rbl_t *rbl)
return closest; /* Ofcourse, we cannot add two identical things */
}
else
tree->head = rbl;
tree->top = rbl;
/* Red-black part of insert */
@ -242,7 +242,7 @@ rbl_t rbl_insert_rbl(rbltree_t *tree, rbl_t *rbl)
}
}
tree->head->color = RBL_BLACK;
tree->top->color = RBL_BLACK;
return rbl;
}
@ -258,9 +258,137 @@ rbl_t rbl_insert(rbltree_t *tree, void *data)
return rbl_insert_rbl(tree, rbl);
}
/* Unlink node from the tree, but keep the node intact */
/* Restore red-black property after violation due to a deletion */
void rbl_delete_fixup(rbl_t *x)
{
rbl_t *w;
while(x != x->tree->top && x->color == RBL_BLACK)
{
if(x == x->parent->left)
{
w = x->parent->right;
if(w->color == RBL_RED)
{
w->color = RBL_BLACK;
x->partent->color = RBL_RED;
rbl_left_rotate(x->parent);
w = x->parent->right;
}
if(w->left->color == RBL_BLACK && w->right->color == RBL_BLACK)
{
w->color = RBL_RED;
x = x->parent;
}
else
{
if(w->right->color == RBL_BLACK)
{
w->left->color = RBL_BLACK;
w->color = RBL_RED;
rbl_right_rotate(w);
w = x->parent->right;
}
w->color = x->parent->color;
x->parent->color = RBL_BLACK;
w->right->color = RBL_BLACK;
rbl_left_rotate(x->parent);
x = x->tree->top;
}
}
else
{
w = x->parent->left;
if(w->color == RBL_RED)
{
w->color = RBL_BLACK;
x->partent->color = RBL_RED;
rbl_right_rotate(x->parent);
w = x->parent->left;
}
if(w->right->color == RBL_BLACK && w->left->color == RBL_BLACK)
{
w->color = RBL_RED;
x = x->parent;
}
else
{
if(w->left->color == RBL_BLACK)
{
w->right->color = RBL_BLACK;
w->color = RBL_RED;
rbl_left_rotate(w);
w = x->parent->left;
}
w->color = x->parent->color;
x->parent->color = RBL_BLACK;
w->left->color = RBL_BLACK;
rbl_right_rotate(x->parent);
x = x->tree->top;
}
}
}
x->color = RBL_BLACK;
}
/* Unlink node from the tree, but keep the node intact. */
rbl_t rbl_unlink_rbl(rbl_t *rbl)
{
rbl_t *x, *y;
/* Binary tree delete */
if(rbl->left && rbl->right)
y = rbl->next;
else
y = rbl;
if(y->left)
x = y->left;
else
x = y->right;
if(x)
x->parent = y->parent;
if(!y->parent)
rbl->tree->top = x;
else
if(y == y->parent->left)
y->parent->left = x;
else
y->parent->right = x;
if(y != rbl)
{
y->left = rbl->left;
y->right = rbl->right;
y->parent = rbl->parent;
if(rbl == rbl->parent->left)
rbl->parent->left = y;
else
rbl->parent->right = y;
}
/* Linked list delete */
if(rbl->prev)
rbl->prev->next = rbl->next;
else
rbl->tree->head = rbl->next;
if(rbl->next)
rbl->next->prev = rbl->prev;
else
rbl->tree->tail = rbl->prev;
/* Red-black part of delete */
if(y->color == RBL_BLACK)
rbl_delete_fixup(x);
return rbl;
}
/* Search node in tree and unlink it */
@ -287,3 +415,17 @@ void rbl_delete(rbltree_t *tree, void *data)
{
free_rbl(rbl_unlink(tree, data));
}
/* Do action for each list entry (in order)
Deletion of entry for which action is called is allowed.
*/
void rbl_foreach(rbltree_t *tree, rbl_action_t *action)
{
rbl_t *rbl, *next;
for(rbl = tree->head; rbl; rbl = next);
{
next = rbl->next;
action(rbl);
}
}

View file

@ -17,11 +17,11 @@
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
$Id: rbl.h,v 1.1.2.2 2000/11/18 18:14:57 guus Exp $
$Id: rbl.h,v 1.1.2.3 2000/11/18 23:21:01 guus Exp $
*/
typedef int (*rbl_compare_t) (const void *, const void *);
typedef void (*rbl_delete_t) (const void *);
typedef void (*rbl_action_t) (const void *);
typedef struct rbl_t
{
@ -48,9 +48,20 @@ typedef struct rbl_t
typedef struct rbltree_t
{
/* callback functions */
rbl_compare_t *compare;
rbl_delete_t *delete;
rbl_action_t *delete;
/* tree part */
struct rbl_t *top;
/* linked list */
struct rbl_t *head;
struct rbl_t *tail;
} rbltree_t;
enum
@ -59,7 +70,7 @@ enum
RBL_BLACK;
};
extern rbl_t *new_rbltree(rbl_compare_t *, rbl_delete_t *);
extern rbl_t *new_rbltree(rbl_compare_t *, rbl_action_t *);
extern void free_rbltree(rbltree_t *);
extern rbl_t *new_rbl(void);
extern void free_rbl(rbl_t *);
@ -72,3 +83,5 @@ extern rbl_t *rbl_delete(rbltree_t *, void *);
extern rbl_t *rbl_insert_rbl(rbltree_t *, rbl_t *);
extern rbl_t *rbl_unlink_rbl(rbltree_t *, rbl_t *);
extern rbl_t *rbl_delete_rbl(rbltree_t *, rbl_t *);
extern void rbl_foreach(rbltree_t *, rbl_action_t *);