haproxy/include/import/eb32tree.h
Willy Tarreau 9b7a617a0e REORG: ebtree: split structures into their own file ebtree-t.h
ebtree is one piece using a lot of inlines and each tree root or node
definition needed by many of our structures requires to parse and
compile all these includes, which is large and painfully slow. Let's
move the very basic definitions to their own file and include it from
ebtree.h.
2021-10-07 01:41:14 +02:00

483 lines
15 KiB
C

/*
* Elastic Binary Trees - macros and structures for operations on 32bit nodes.
* Version 6.0.6
* (C) 2002-2011 - Willy Tarreau <w@1wt.eu>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation, version 2.1
* exclusively.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef _EB32TREE_H
#define _EB32TREE_H
#include "ebtree.h"
/* Return the structure of type <type> whose member <member> points to <ptr> */
#define eb32_entry(ptr, type, member) container_of(ptr, type, member)
/*
* Exported functions and macros.
* Many of them are always inlined because they are extremely small, and
* are generally called at most once or twice in a program.
*/
/* Return leftmost node in the tree, or NULL if none */
static inline struct eb32_node *eb32_first(struct eb_root *root)
{
return eb32_entry(eb_first(root), struct eb32_node, node);
}
/* Return rightmost node in the tree, or NULL if none */
static inline struct eb32_node *eb32_last(struct eb_root *root)
{
return eb32_entry(eb_last(root), struct eb32_node, node);
}
/* Return next node in the tree, or NULL if none */
static inline struct eb32_node *eb32_next(struct eb32_node *eb32)
{
return eb32_entry(eb_next(&eb32->node), struct eb32_node, node);
}
/* Return previous node in the tree, or NULL if none */
static inline struct eb32_node *eb32_prev(struct eb32_node *eb32)
{
return eb32_entry(eb_prev(&eb32->node), struct eb32_node, node);
}
/* Return next leaf node within a duplicate sub-tree, or NULL if none. */
static inline struct eb32_node *eb32_next_dup(struct eb32_node *eb32)
{
return eb32_entry(eb_next_dup(&eb32->node), struct eb32_node, node);
}
/* Return previous leaf node within a duplicate sub-tree, or NULL if none. */
static inline struct eb32_node *eb32_prev_dup(struct eb32_node *eb32)
{
return eb32_entry(eb_prev_dup(&eb32->node), struct eb32_node, node);
}
/* Return next node in the tree, skipping duplicates, or NULL if none */
static inline struct eb32_node *eb32_next_unique(struct eb32_node *eb32)
{
return eb32_entry(eb_next_unique(&eb32->node), struct eb32_node, node);
}
/* Return previous node in the tree, skipping duplicates, or NULL if none */
static inline struct eb32_node *eb32_prev_unique(struct eb32_node *eb32)
{
return eb32_entry(eb_prev_unique(&eb32->node), struct eb32_node, node);
}
/* Delete node from the tree if it was linked in. Mark the node unused. Note
* that this function relies on a non-inlined generic function: eb_delete.
*/
static inline void eb32_delete(struct eb32_node *eb32)
{
eb_delete(&eb32->node);
}
/*
* The following functions are not inlined by default. They are declared
* in eb32tree.c, which simply relies on their inline version.
*/
struct eb32_node *eb32_lookup(struct eb_root *root, u32 x);
struct eb32_node *eb32i_lookup(struct eb_root *root, s32 x);
struct eb32_node *eb32_lookup_le(struct eb_root *root, u32 x);
struct eb32_node *eb32_lookup_ge(struct eb_root *root, u32 x);
struct eb32_node *eb32_insert(struct eb_root *root, struct eb32_node *new);
struct eb32_node *eb32i_insert(struct eb_root *root, struct eb32_node *new);
/*
* The following functions are less likely to be used directly, because their
* code is larger. The non-inlined version is preferred.
*/
/* Delete node from the tree if it was linked in. Mark the node unused. */
static forceinline void __eb32_delete(struct eb32_node *eb32)
{
__eb_delete(&eb32->node);
}
/*
* Find the first occurrence of a key in the tree <root>. If none can be
* found, return NULL.
*/
static forceinline struct eb32_node *__eb32_lookup(struct eb_root *root, u32 x)
{
struct eb32_node *node;
eb_troot_t *troot;
u32 y;
int node_bit;
troot = root->b[EB_LEFT];
if (unlikely(troot == NULL))
return NULL;
while (1) {
if ((eb_gettag(troot) == EB_LEAF)) {
node = container_of(eb_untag(troot, EB_LEAF),
struct eb32_node, node.branches);
if (node->key == x)
return node;
else
return NULL;
}
node = container_of(eb_untag(troot, EB_NODE),
struct eb32_node, node.branches);
node_bit = node->node.bit;
y = node->key ^ x;
if (!y) {
/* Either we found the node which holds the key, or
* we have a dup tree. In the later case, we have to
* walk it down left to get the first entry.
*/
if (node_bit < 0) {
troot = node->node.branches.b[EB_LEFT];
while (eb_gettag(troot) != EB_LEAF)
troot = (eb_untag(troot, EB_NODE))->b[EB_LEFT];
node = container_of(eb_untag(troot, EB_LEAF),
struct eb32_node, node.branches);
}
return node;
}
if ((y >> node_bit) >= EB_NODE_BRANCHES)
return NULL; /* no more common bits */
troot = node->node.branches.b[(x >> node_bit) & EB_NODE_BRANCH_MASK];
}
}
/*
* Find the first occurrence of a signed key in the tree <root>. If none can
* be found, return NULL.
*/
static forceinline struct eb32_node *__eb32i_lookup(struct eb_root *root, s32 x)
{
struct eb32_node *node;
eb_troot_t *troot;
u32 key = x ^ 0x80000000;
u32 y;
int node_bit;
troot = root->b[EB_LEFT];
if (unlikely(troot == NULL))
return NULL;
while (1) {
if ((eb_gettag(troot) == EB_LEAF)) {
node = container_of(eb_untag(troot, EB_LEAF),
struct eb32_node, node.branches);
if (node->key == (u32)x)
return node;
else
return NULL;
}
node = container_of(eb_untag(troot, EB_NODE),
struct eb32_node, node.branches);
node_bit = node->node.bit;
y = node->key ^ x;
if (!y) {
/* Either we found the node which holds the key, or
* we have a dup tree. In the later case, we have to
* walk it down left to get the first entry.
*/
if (node_bit < 0) {
troot = node->node.branches.b[EB_LEFT];
while (eb_gettag(troot) != EB_LEAF)
troot = (eb_untag(troot, EB_NODE))->b[EB_LEFT];
node = container_of(eb_untag(troot, EB_LEAF),
struct eb32_node, node.branches);
}
return node;
}
if ((y >> node_bit) >= EB_NODE_BRANCHES)
return NULL; /* no more common bits */
troot = node->node.branches.b[(key >> node_bit) & EB_NODE_BRANCH_MASK];
}
}
/* Insert eb32_node <new> into subtree starting at node root <root>.
* Only new->key needs be set with the key. The eb32_node is returned.
* If root->b[EB_RGHT]==1, the tree may only contain unique keys.
*/
static forceinline struct eb32_node *
__eb32_insert(struct eb_root *root, struct eb32_node *new) {
struct eb32_node *old;
unsigned int side;
eb_troot_t *troot, **up_ptr;
u32 newkey; /* caching the key saves approximately one cycle */
eb_troot_t *root_right;
eb_troot_t *new_left, *new_rght;
eb_troot_t *new_leaf;
int old_node_bit;
side = EB_LEFT;
troot = root->b[EB_LEFT];
root_right = root->b[EB_RGHT];
if (unlikely(troot == NULL)) {
/* Tree is empty, insert the leaf part below the left branch */
root->b[EB_LEFT] = eb_dotag(&new->node.branches, EB_LEAF);
new->node.leaf_p = eb_dotag(root, EB_LEFT);
new->node.node_p = NULL; /* node part unused */
return new;
}
/* The tree descent is fairly easy :
* - first, check if we have reached a leaf node
* - second, check if we have gone too far
* - third, reiterate
* Everywhere, we use <new> for the node node we are inserting, <root>
* for the node we attach it to, and <old> for the node we are
* displacing below <new>. <troot> will always point to the future node
* (tagged with its type). <side> carries the side the node <new> is
* attached to below its parent, which is also where previous node
* was attached. <newkey> carries the key being inserted.
*/
newkey = new->key;
while (1) {
if (eb_gettag(troot) == EB_LEAF) {
/* insert above a leaf */
old = container_of(eb_untag(troot, EB_LEAF),
struct eb32_node, node.branches);
new->node.node_p = old->node.leaf_p;
up_ptr = &old->node.leaf_p;
break;
}
/* OK we're walking down this link */
old = container_of(eb_untag(troot, EB_NODE),
struct eb32_node, node.branches);
old_node_bit = old->node.bit;
/* Stop going down when we don't have common bits anymore. We
* also stop in front of a duplicates tree because it means we
* have to insert above.
*/
if ((old_node_bit < 0) || /* we're above a duplicate tree, stop here */
(((new->key ^ old->key) >> old_node_bit) >= EB_NODE_BRANCHES)) {
/* The tree did not contain the key, so we insert <new> before the node
* <old>, and set ->bit to designate the lowest bit position in <new>
* which applies to ->branches.b[].
*/
new->node.node_p = old->node.node_p;
up_ptr = &old->node.node_p;
break;
}
/* walk down */
root = &old->node.branches;
side = (newkey >> old_node_bit) & EB_NODE_BRANCH_MASK;
troot = root->b[side];
}
new_left = eb_dotag(&new->node.branches, EB_LEFT);
new_rght = eb_dotag(&new->node.branches, EB_RGHT);
new_leaf = eb_dotag(&new->node.branches, EB_LEAF);
/* We need the common higher bits between new->key and old->key.
* What differences are there between new->key and the node here ?
* NOTE that bit(new) is always < bit(root) because highest
* bit of new->key and old->key are identical here (otherwise they
* would sit on different branches).
*/
// note that if EB_NODE_BITS > 1, we should check that it's still >= 0
new->node.bit = flsnz(new->key ^ old->key) - EB_NODE_BITS;
if (new->key == old->key) {
new->node.bit = -1; /* mark as new dup tree, just in case */
if (likely(eb_gettag(root_right))) {
/* we refuse to duplicate this key if the tree is
* tagged as containing only unique keys.
*/
return old;
}
if (eb_gettag(troot) != EB_LEAF) {
/* there was already a dup tree below */
struct eb_node *ret;
ret = eb_insert_dup(&old->node, &new->node);
return container_of(ret, struct eb32_node, node);
}
/* otherwise fall through */
}
if (new->key >= old->key) {
new->node.branches.b[EB_LEFT] = troot;
new->node.branches.b[EB_RGHT] = new_leaf;
new->node.leaf_p = new_rght;
*up_ptr = new_left;
}
else {
new->node.branches.b[EB_LEFT] = new_leaf;
new->node.branches.b[EB_RGHT] = troot;
new->node.leaf_p = new_left;
*up_ptr = new_rght;
}
/* Ok, now we are inserting <new> between <root> and <old>. <old>'s
* parent is already set to <new>, and the <root>'s branch is still in
* <side>. Update the root's leaf till we have it. Note that we can also
* find the side by checking the side of new->node.node_p.
*/
root->b[side] = eb_dotag(&new->node.branches, EB_NODE);
return new;
}
/* Insert eb32_node <new> into subtree starting at node root <root>, using
* signed keys. Only new->key needs be set with the key. The eb32_node
* is returned. If root->b[EB_RGHT]==1, the tree may only contain unique keys.
*/
static forceinline struct eb32_node *
__eb32i_insert(struct eb_root *root, struct eb32_node *new) {
struct eb32_node *old;
unsigned int side;
eb_troot_t *troot, **up_ptr;
int newkey; /* caching the key saves approximately one cycle */
eb_troot_t *root_right;
eb_troot_t *new_left, *new_rght;
eb_troot_t *new_leaf;
int old_node_bit;
side = EB_LEFT;
troot = root->b[EB_LEFT];
root_right = root->b[EB_RGHT];
if (unlikely(troot == NULL)) {
/* Tree is empty, insert the leaf part below the left branch */
root->b[EB_LEFT] = eb_dotag(&new->node.branches, EB_LEAF);
new->node.leaf_p = eb_dotag(root, EB_LEFT);
new->node.node_p = NULL; /* node part unused */
return new;
}
/* The tree descent is fairly easy :
* - first, check if we have reached a leaf node
* - second, check if we have gone too far
* - third, reiterate
* Everywhere, we use <new> for the node node we are inserting, <root>
* for the node we attach it to, and <old> for the node we are
* displacing below <new>. <troot> will always point to the future node
* (tagged with its type). <side> carries the side the node <new> is
* attached to below its parent, which is also where previous node
* was attached. <newkey> carries a high bit shift of the key being
* inserted in order to have negative keys stored before positive
* ones.
*/
newkey = new->key + 0x80000000;
while (1) {
if (eb_gettag(troot) == EB_LEAF) {
old = container_of(eb_untag(troot, EB_LEAF),
struct eb32_node, node.branches);
new->node.node_p = old->node.leaf_p;
up_ptr = &old->node.leaf_p;
break;
}
/* OK we're walking down this link */
old = container_of(eb_untag(troot, EB_NODE),
struct eb32_node, node.branches);
old_node_bit = old->node.bit;
/* Stop going down when we don't have common bits anymore. We
* also stop in front of a duplicates tree because it means we
* have to insert above.
*/
if ((old_node_bit < 0) || /* we're above a duplicate tree, stop here */
(((new->key ^ old->key) >> old_node_bit) >= EB_NODE_BRANCHES)) {
/* The tree did not contain the key, so we insert <new> before the node
* <old>, and set ->bit to designate the lowest bit position in <new>
* which applies to ->branches.b[].
*/
new->node.node_p = old->node.node_p;
up_ptr = &old->node.node_p;
break;
}
/* walk down */
root = &old->node.branches;
side = (newkey >> old_node_bit) & EB_NODE_BRANCH_MASK;
troot = root->b[side];
}
new_left = eb_dotag(&new->node.branches, EB_LEFT);
new_rght = eb_dotag(&new->node.branches, EB_RGHT);
new_leaf = eb_dotag(&new->node.branches, EB_LEAF);
/* We need the common higher bits between new->key and old->key.
* What differences are there between new->key and the node here ?
* NOTE that bit(new) is always < bit(root) because highest
* bit of new->key and old->key are identical here (otherwise they
* would sit on different branches).
*/
// note that if EB_NODE_BITS > 1, we should check that it's still >= 0
new->node.bit = flsnz(new->key ^ old->key) - EB_NODE_BITS;
if (new->key == old->key) {
new->node.bit = -1; /* mark as new dup tree, just in case */
if (likely(eb_gettag(root_right))) {
/* we refuse to duplicate this key if the tree is
* tagged as containing only unique keys.
*/
return old;
}
if (eb_gettag(troot) != EB_LEAF) {
/* there was already a dup tree below */
struct eb_node *ret;
ret = eb_insert_dup(&old->node, &new->node);
return container_of(ret, struct eb32_node, node);
}
/* otherwise fall through */
}
if ((s32)new->key >= (s32)old->key) {
new->node.branches.b[EB_LEFT] = troot;
new->node.branches.b[EB_RGHT] = new_leaf;
new->node.leaf_p = new_rght;
*up_ptr = new_left;
}
else {
new->node.branches.b[EB_LEFT] = new_leaf;
new->node.branches.b[EB_RGHT] = troot;
new->node.leaf_p = new_left;
*up_ptr = new_rght;
}
/* Ok, now we are inserting <new> between <root> and <old>. <old>'s
* parent is already set to <new>, and the <root>'s branch is still in
* <side>. Update the root's leaf till we have it. Note that we can also
* find the side by checking the side of new->node.node_p.
*/
root->b[side] = eb_dotag(&new->node.branches, EB_NODE);
return new;
}
#endif /* _EB32_TREE_H */