ldns  1.7.0
Macros | Functions | Variables
rbtree.c File Reference

Implementation of a redblack tree. More...

Go to the source code of this file.

Macros

#define BLACK   0
 Node colour black. More...
 
#define RED   1
 Node colour red. More...
 

Functions

ldns_rbtree_tldns_rbtree_create (int(*cmpf)(const void *, const void *))
 Create new tree (malloced) with given key compare function. More...
 
void ldns_rbtree_init (ldns_rbtree_t *rbtree, int(*cmpf)(const void *, const void *))
 Init a new tree (malloced by caller) with given key compare function. More...
 
void ldns_rbtree_free (ldns_rbtree_t *rbtree)
 Free the complete tree (but not its keys) More...
 
void ldns_rbtree_insert_vref (ldns_rbnode_t *data, void *rbtree)
 Insert data into the tree (reversed arguments, for use as callback) More...
 
ldns_rbnode_tldns_rbtree_insert (ldns_rbtree_t *rbtree, ldns_rbnode_t *data)
 Insert data into the tree. More...
 
ldns_rbnode_tldns_rbtree_search (ldns_rbtree_t *rbtree, const void *key)
 Find key in tree. More...
 
ldns_rbnode_tldns_rbtree_delete (ldns_rbtree_t *rbtree, const void *key)
 Delete element from tree. More...
 
int ldns_rbtree_find_less_equal (ldns_rbtree_t *rbtree, const void *key, ldns_rbnode_t **result)
 Find, but match does not have to be exact. More...
 
ldns_rbnode_tldns_rbtree_first (const ldns_rbtree_t *rbtree)
 Returns first (smallest) node in the tree. More...
 
ldns_rbnode_tldns_rbtree_last (const ldns_rbtree_t *rbtree)
 Returns last (largest) node in the tree. More...
 
ldns_rbnode_tldns_rbtree_next (ldns_rbnode_t *node)
 Returns next larger node in the tree. More...
 
ldns_rbnode_tldns_rbtree_previous (ldns_rbnode_t *node)
 Returns previous smaller node in the tree. More...
 
ldns_rbtree_tldns_rbtree_split (ldns_rbtree_t *tree, size_t elements)
 split off elements number of elements from the start of the name tree and return a new tree More...
 
void ldns_rbtree_join (ldns_rbtree_t *tree1, ldns_rbtree_t *tree2)
 add all node from the second tree to the first (removing them from the second), and fix up nsec(3)s if present More...
 
void ldns_traverse_postorder (ldns_rbtree_t *tree, void(*func)(ldns_rbnode_t *, void *), void *arg)
 Call function for all elements in the redblack tree, such that leaf elements are called before parent elements. More...
 

Variables

ldns_rbnode_t ldns_rbtree_null_node
 the NULL node, global alloc More...
 

Detailed Description

Implementation of a redblack tree.

Definition in file rbtree.c.

Macro Definition Documentation

§ BLACK

#define BLACK   0

Node colour black.

Definition at line 50 of file rbtree.c.

§ RED

#define RED   1

Node colour red.

Definition at line 52 of file rbtree.c.

Function Documentation

§ ldns_rbtree_create()

ldns_rbtree_t* ldns_rbtree_create ( int(*)(const void *, const void *)  cmpf)

Create new tree (malloced) with given key compare function.

Parameters
cmpfcompare function (like strcmp) takes pointers to two keys.
Returns
: new tree, empty.

Definition at line 80 of file rbtree.c.

References LDNS_MALLOC, and ldns_rbtree_init().

§ ldns_rbtree_init()

void ldns_rbtree_init ( ldns_rbtree_t rbtree,
int(*)(const void *, const void *)  cmpf 
)

Init a new tree (malloced by caller) with given key compare function.

Parameters
rbtreeuninitialised memory for new tree, returned empty.
cmpfcompare function (like strcmp) takes pointers to two keys.

Definition at line 97 of file rbtree.c.

References ldns_rbtree_t::cmp, ldns_rbtree_t::count, LDNS_RBTREE_NULL, and ldns_rbtree_t::root.

§ ldns_rbtree_free()

void ldns_rbtree_free ( ldns_rbtree_t rbtree)

Free the complete tree (but not its keys)

Parameters
rbtreeThe tree to free

Definition at line 106 of file rbtree.c.

References LDNS_FREE.

§ ldns_rbtree_insert_vref()

void ldns_rbtree_insert_vref ( ldns_rbnode_t data,
void *  rbtree 
)

Insert data into the tree (reversed arguments, for use as callback)

Parameters
[in]dataelement to insert
[out]rbtreetree to insert in to
Returns
data ptr or NULL if key is already present

Definition at line 229 of file rbtree.c.

References ldns_rbtree_insert().

§ ldns_rbtree_insert()

ldns_rbnode_t* ldns_rbtree_insert ( ldns_rbtree_t rbtree,
ldns_rbnode_t data 
)

Insert data into the tree.

Parameters
rbtreetree to insert to.
dataelement to insert.
Returns
: data ptr or NULL if key already present.

Definition at line 242 of file rbtree.c.

References ldns_rbtree_t::cmp, ldns_rbnode_t::color, ldns_rbtree_t::count, ldns_rbnode_t::key, LDNS_RBTREE_NULL, ldns_rbnode_t::left, ldns_rbnode_t::parent, RED, ldns_rbnode_t::right, and ldns_rbtree_t::root.

§ ldns_rbtree_search()

ldns_rbnode_t* ldns_rbtree_search ( ldns_rbtree_t rbtree,
const void *  key 
)

Find key in tree.

Returns NULL if not found.

Parameters
rbtreetree to find in.
keykey that must match.
Returns
: node that fits or NULL.

Definition at line 294 of file rbtree.c.

References ldns_rbtree_find_less_equal().

§ ldns_rbtree_delete()

ldns_rbnode_t* ldns_rbtree_delete ( ldns_rbtree_t rbtree,
const void *  key 
)

Delete element from tree.

Parameters
rbtreetree to delete from.
keykey of item to delete.
Returns
: node that is now unlinked from the tree. User to delete it. returns 0 if node not present

Definition at line 336 of file rbtree.c.

References ldns_rbtree_t::count, LDNS_RBTREE_NULL, ldns_rbtree_search(), ldns_rbnode_t::left, and ldns_rbnode_t::right.

§ ldns_rbtree_find_less_equal()

int ldns_rbtree_find_less_equal ( ldns_rbtree_t rbtree,
const void *  key,
ldns_rbnode_t **  result 
)

Find, but match does not have to be exact.

Parameters
rbtreetree to find in.
keykey to find position of.
resultset to the exact node if present, otherwise to element that precedes the position of key in the tree. NULL if no smaller element.
Returns
: true if exact match in result. Else result points to <= element, or NULL if key is smaller than the smallest key.

Definition at line 514 of file rbtree.c.

References ldns_rbtree_t::cmp, ldns_rbnode_t::key, LDNS_RBTREE_NULL, ldns_rbnode_t::left, ldns_rbnode_t::right, and ldns_rbtree_t::root.

§ ldns_rbtree_first()

ldns_rbnode_t* ldns_rbtree_first ( const ldns_rbtree_t rbtree)

Returns first (smallest) node in the tree.

Parameters
rbtreetree
Returns
: smallest element or NULL if tree empty.

Definition at line 548 of file rbtree.c.

References LDNS_RBTREE_NULL, ldns_rbnode_t::left, and ldns_rbtree_t::root.

§ ldns_rbtree_last()

ldns_rbnode_t* ldns_rbtree_last ( const ldns_rbtree_t rbtree)

Returns last (largest) node in the tree.

Parameters
rbtreetree
Returns
: largest element or NULL if tree empty.

Definition at line 559 of file rbtree.c.

References LDNS_RBTREE_NULL, ldns_rbnode_t::right, and ldns_rbtree_t::root.

§ ldns_rbtree_next()

ldns_rbnode_t* ldns_rbtree_next ( ldns_rbnode_t rbtree)

Returns next larger node in the tree.

Parameters
rbtreetree
Returns
: next larger element or NULL if no larger in tree.

Definition at line 574 of file rbtree.c.

References LDNS_RBTREE_NULL, ldns_rbnode_t::left, ldns_rbnode_t::parent, and ldns_rbnode_t::right.

§ ldns_rbtree_previous()

ldns_rbnode_t* ldns_rbtree_previous ( ldns_rbnode_t rbtree)

Returns previous smaller node in the tree.

Parameters
rbtreetree
Returns
: previous smaller element or NULL if no previous in tree.

Definition at line 595 of file rbtree.c.

References LDNS_RBTREE_NULL, ldns_rbnode_t::left, ldns_rbnode_t::parent, and ldns_rbnode_t::right.

§ ldns_rbtree_split()

ldns_rbtree_t* ldns_rbtree_split ( ldns_rbtree_t tree,
size_t  elements 
)

split off elements number of elements from the start of the name tree and return a new tree

split off 'elements' number of elements from the start of the name tree and return a new tree containing those elements

Definition at line 620 of file rbtree.c.

References ldns_rbtree_t::cmp, ldns_rbnode_t::key, ldns_rbtree_create(), ldns_rbtree_delete(), ldns_rbtree_first(), ldns_rbtree_insert(), and LDNS_RBTREE_NULL.

§ ldns_rbtree_join()

void ldns_rbtree_join ( ldns_rbtree_t tree1,
ldns_rbtree_t tree2 
)

add all node from the second tree to the first (removing them from the second), and fix up nsec(3)s if present

Definition at line 646 of file rbtree.c.

References ldns_rbtree_insert_vref(), and ldns_traverse_postorder().

§ ldns_traverse_postorder()

void ldns_traverse_postorder ( ldns_rbtree_t tree,
void(*)(ldns_rbnode_t *, void *)  func,
void *  arg 
)

Call function for all elements in the redblack tree, such that leaf elements are called before parent elements.

So that all elements can be safely free()d. Note that your function must not remove the nodes from the tree. Since that may trigger rebalances of the rbtree.

Parameters
treethe tree
funcfunction called with element and user arg. The function must not alter the rbtree.
arguser argument.

Definition at line 666 of file rbtree.c.

Variable Documentation

§ ldns_rbtree_null_node

ldns_rbnode_t ldns_rbtree_null_node
Initial value:
= {
NULL,
NULL,
0
}
ldns_rbnode_t ldns_rbtree_null_node
the NULL node, global alloc
Definition: rbtree.c:55

the NULL node, global alloc

the global empty node

Definition at line 55 of file rbtree.c.