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add rbtree

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This commit is contained in:
Nick Peng
2018-06-24 18:42:39 +08:00
parent 5153d6cb51
commit aaca2494e4
8 changed files with 903 additions and 18 deletions
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1
etc/smartdns/smartdns.conf
View File

@@ -41,3 +41,4 @@ server 202.141.162.123:53
# remote tcp dns server list
# server-tcp [IP]:[PORT], default port is 53
# server-tcp 114.114.114.114

2
src/Makefile
View File

@@ -1,6 +1,6 @@
BIN=smartdns
OBJS=smartdns.o fast_ping.o lib/bitops.o dns_client.o dns_server.o dns.o util.o tlog.o conf.o
OBJS=smartdns.o fast_ping.o lib/bitops.o dns_client.o dns_server.o dns.o util.o tlog.o conf.o lib/rbtree.o
CFLAGS=-g -O0 -Wall -Wstrict-prototypes -fno-omit-frame-pointer -Wstrict-aliasing
CFLAGS +=-Iinclude
CFLAGS += -DBASE_FILE_NAME=\"$(notdir $<)\"

40
src/dns_server.c
View File

@@ -99,13 +99,16 @@ struct dns_request {
int has_ptr;
int has_cname;
char alias[DNS_MAX_CNAME_LEN];
char cname[DNS_MAX_CNAME_LEN];
int ttl_cname;
int has_ipv4;
int ping_ttl_v4;
int ttl_v4;
unsigned char ipv4_addr[DNS_RR_A_LEN];
int has_ipv6;
int ping_ttl_v6;
int ttl_v6;
unsigned char ipv6_addr[DNS_RR_AAAA_LEN];
@@ -170,19 +173,19 @@ static int _dns_add_rrs(struct dns_packet *packet, struct dns_request *request)
}
if (request->has_cname) {
ret |= dns_add_CNAME(packet, DNS_RRS_AN, request->domain, 30, request->alias);
domain = request->alias;
ret |= dns_add_CNAME(packet, DNS_RRS_AN, request->domain, request->ttl_cname, request->cname);
domain = request->cname;
}
if (request->has_ipv4 && request->qtype == DNS_T_A) {
ret |= dns_add_A(packet, DNS_RRS_AN, domain, 30, request->ipv4_addr);
ret |= dns_add_A(packet, DNS_RRS_AN, domain, request->ttl_v4, request->ipv4_addr);
}
if (request->has_ipv6 && request->qtype == DNS_T_AAAA) {
if (request->has_ipv4) {
ret |= dns_add_A(packet, DNS_RRS_AN, domain, 30, request->ipv4_addr);
ret |= dns_add_A(packet, DNS_RRS_AN, domain, request->ttl_v4, request->ipv4_addr);
}
ret |= dns_add_AAAA(packet, DNS_RRS_AN, domain, 30, request->ipv6_addr);
ret |= dns_add_AAAA(packet, DNS_RRS_AN, domain, request->ttl_v6, request->ipv6_addr);
}
if (request->has_soa) {
@@ -345,8 +348,8 @@ void _dns_server_ping_result(struct ping_host_struct *ping_host, const char *hos
case AF_INET: {
struct sockaddr_in *addr_in;
addr_in = (struct sockaddr_in *)addr;
if (request->ttl_v4 > rtt) {
request->ttl_v4 = rtt;
if (request->ping_ttl_v4 > rtt) {
request->ping_ttl_v4 = rtt;
request->has_ipv4 = 1;
memcpy(request->ipv4_addr, &addr_in->sin_addr.s_addr, 4);
}
@@ -355,14 +358,14 @@ void _dns_server_ping_result(struct ping_host_struct *ping_host, const char *hos
struct sockaddr_in6 *addr_in6;
addr_in6 = (struct sockaddr_in6 *)addr;
if (IN6_IS_ADDR_V4MAPPED(&addr_in6->sin6_addr)) {
if (request->ttl_v4 > rtt) {
request->ttl_v4 = rtt;
if (request->ping_ttl_v4 > rtt) {
request->ping_ttl_v4 = rtt;
request->has_ipv4 = 1;
memcpy(request->ipv4_addr, addr_in6->sin6_addr.s6_addr + 12, 4);
}
} else {
if (request->ttl_v6 > rtt) {
request->ttl_v6 = rtt;
if (request->ping_ttl_v6 > rtt) {
request->ping_ttl_v6 = rtt;
request->has_ipv6 = 1;
memcpy(request->ipv6_addr, addr_in6->sin6_addr.s6_addr, 16);
}
@@ -479,7 +482,7 @@ static int _dns_server_process_answer(struct dns_request *request, char *domain,
tlog(TLOG_DEBUG, "domain: %s TTL:%d IP: %d.%d.%d.%d", name, ttl, addr[0], addr[1], addr[2], addr[3]);
if (strncmp(name, domain, DNS_MAX_CNAME_LEN) != 0 && strncmp(request->alias, name, DNS_MAX_CNAME_LEN) != 0) {
if (strncmp(name, domain, DNS_MAX_CNAME_LEN) != 0 && strncmp(request->cname, name, DNS_MAX_CNAME_LEN) != 0) {
_dns_server_request_release(request);
break;
}
@@ -492,6 +495,7 @@ static int _dns_server_process_answer(struct dns_request *request, char *domain,
if (request->has_ipv4 == 0) {
memcpy(request->ipv4_addr, addr, DNS_RR_A_LEN);
request->ttl_v4 = ttl;
request->has_ipv4 = 1;
}
if (_dns_ip_address_check_add(request, addr, DNS_T_A) != 0) {
@@ -515,13 +519,14 @@ static int _dns_server_process_answer(struct dns_request *request, char *domain,
tlog(TLOG_DEBUG, "domain: %s TTL: %d IP: %.2x%.2x:%.2x%.2x:%.2x%.2x:%.2x%.2x:%.2x%.2x:%.2x%.2x:%.2x%.2x:%.2x%.2x", name, ttl, addr[0], addr[1],
addr[2], addr[3], addr[4], addr[5], addr[6], addr[7], addr[8], addr[9], addr[10], addr[11], addr[12], addr[13], addr[14], addr[15]);
if (strncmp(name, domain, DNS_MAX_CNAME_LEN) != 0 && strncmp(request->alias, name, DNS_MAX_CNAME_LEN) != 0) {
if (strncmp(name, domain, DNS_MAX_CNAME_LEN) != 0 && strncmp(request->cname, name, DNS_MAX_CNAME_LEN) != 0) {
_dns_server_request_release(request);
break;
}
if (request->has_ipv6 == 0) {
memcpy(request->ipv6_addr, addr, DNS_RR_AAAA_LEN);
request->ttl_v6 = ttl;
request->has_ipv6 = 1;
}
@@ -546,7 +551,8 @@ static int _dns_server_process_answer(struct dns_request *request, char *domain,
char cname[128];
dns_get_CNAME(rrs, name, 128, &ttl, cname, 128);
tlog(TLOG_DEBUG, "%s %d : %s\n", name, ttl, cname);
strncpy(request->alias, cname, DNS_MAX_CNAME_LEN);
strncpy(request->cname, cname, DNS_MAX_CNAME_LEN);
request->ttl_cname = ttl;
request->has_cname = 1;
} break;
case DNS_T_SOA: {
@@ -690,8 +696,8 @@ static int _dns_server_recv(unsigned char *inpacket, int inpacket_len, struct so
request = malloc(sizeof(*request));
memset(request, 0, sizeof(*request));
pthread_mutex_init(&request->ip_map_lock, 0);
request->ttl_v4 = -1;
request->ttl_v6 = -1;
request->ping_ttl_v4 = -1;
request->ping_ttl_v6 = -1;
request->rcode = DNS_RC_SERVFAIL;
if (request == NULL) {
tlog(TLOG_ERROR, "malloc failed.\n");

2
src/include/cache.h
View File

@@ -13,6 +13,8 @@ struct cache_head *cache_new(int hashsize, void (*item_free)(struct cache_head *
int cache_add(struct cache_head *head, struct cache_node *node, void *key, int key_len);
int cache_del(struct cache_node *node);
struct cache_node *cache_lookup(struct cache_head *head, void *key, int key_len);
int cache_update(struct cache_head *head, void *key, int key_len);

287
src/include/rbtree.h Normal file
View File

@@ -0,0 +1,287 @@
#ifndef _GENERIC_RBTREE_H
#define _GENERIC_RBTREE_H
#include <stddef.h>
struct rb_node {
unsigned long __rb_parent_color;
struct rb_node *rb_right;
struct rb_node *rb_left;
} __attribute__((aligned(sizeof(long))));
/* The alignment might seem pointless, but allegedly CRIS needs it */
struct rb_root {
struct rb_node *rb_node;
};
#define rb_parent(r) ((struct rb_node *)((r)->__rb_parent_color & ~3))
#define RB_ROOT \
(struct rb_root) \
{ \
NULL, \
}
#define rb_entry(ptr, type, member) container_of(ptr, type, member)
#define RB_EMPTY_ROOT(root) ((root)->rb_node == NULL)
/* 'empty' nodes are nodes that are known not to be inserted in an rbtree */
#define RB_EMPTY_NODE(node) ((node)->__rb_parent_color == (unsigned long)(node))
#define RB_CLEAR_NODE(node) ((node)->__rb_parent_color = (unsigned long)(node))
extern void rb_insert_color(struct rb_node *, struct rb_root *);
extern void rb_erase(struct rb_node *, struct rb_root *);
/* Find logical next and previous nodes in a tree */
extern struct rb_node *rb_next(const struct rb_node *);
extern struct rb_node *rb_prev(const struct rb_node *);
extern struct rb_node *rb_first(const struct rb_root *);
extern struct rb_node *rb_last(const struct rb_root *);
/* Postorder iteration - always visit the parent after its children */
extern struct rb_node *rb_first_postorder(const struct rb_root *);
extern struct rb_node *rb_next_postorder(const struct rb_node *);
/* Fast replacement of a single node without remove/rebalance/add/rebalance */
extern void rb_replace_node(struct rb_node *victim, struct rb_node *new_node, struct rb_root *root);
static inline void rb_link_node(struct rb_node *node, struct rb_node *parent, struct rb_node **rb_link)
{
node->__rb_parent_color = (unsigned long)parent;
node->rb_left = node->rb_right = NULL;
*rb_link = node;
}
#define rb_entry_safe(ptr, type, member) \
({ \
typeof(ptr) ____ptr = (ptr); \
____ptr ? rb_entry(____ptr, type, member) : NULL; \
})
/*
* Handy for checking that we are not deleting an entry that is
* already in a list, found in block/{blk-throttle,cfq-iosched}.c,
* probably should be moved to lib/rbtree.c...
*/
static inline void rb_erase_init(struct rb_node *n, struct rb_root *root)
{
rb_erase(n, root);
RB_CLEAR_NODE(n);
}
/*
* Please note - only struct rb_augment_callbacks and the prototypes for
* rb_insert_augmented() and rb_erase_augmented() are intended to be public.
* The rest are implementation details you are not expected to depend on.
*
* See Documentation/rbtree.txt for documentation and samples.
*/
struct rb_augment_callbacks {
void (*propagate)(struct rb_node *node, struct rb_node *stop);
void (*copy)(struct rb_node *old_node, struct rb_node *new_node);
void (*rotate)(struct rb_node *old_node, struct rb_node *new_node);
};
extern void __rb_insert_augmented(struct rb_node *node, struct rb_root *root,
void (*augment_rotate)(struct rb_node *old_node, struct rb_node *new_node));
/*
* Fixup the rbtree and update the augmented information when rebalancing.
*
* On insertion, the user must update the augmented information on the path
* leading to the inserted node, then call rb_link_node() as usual and
* rb_augment_inserted() instead of the usual rb_insert_color() call.
* If rb_augment_inserted() rebalances the rbtree, it will callback into
* a user provided function to update the augmented information on the
* affected subtrees.
*/
static inline void
rb_insert_augmented(struct rb_node *node, struct rb_root *root,
const struct rb_augment_callbacks *augment)
{
__rb_insert_augmented(node, root, augment->rotate);
}
#define RB_DECLARE_CALLBACKS(rbstatic, rbname, rbstruct, rbfield, \
rbtype, rbaugmented, rbcompute) \
static inline void \
rbname ## _propagate(struct rb_node *rb, struct rb_node *stop) \
{ \
while (rb != stop) { \
rbstruct *node = rb_entry(rb, rbstruct, rbfield); \
rbtype augmented = rbcompute(node); \
if (node->rbaugmented == augmented) \
break; \
node->rbaugmented = augmented; \
rb = rb_parent(&node->rbfield); \
} \
} \
static inline void \
rbname ## _copy(struct rb_node *rb_old, struct rb_node *rb_new) \
{ \
rbstruct *old_node = rb_entry(rb_old, rbstruct, rbfield); \
rbstruct *new_node = rb_entry(rb_new, rbstruct, rbfield); \
new_node->rbaugmented = old_node->rbaugmented; \
} \
static void \
rbname ## _rotate(struct rb_node *rb_old, struct rb_node *rb_new) \
{ \
rbstruct *old_node = rb_entry(rb_old, rbstruct, rbfield); \
rbstruct *new_node = rb_entry(rb_new, rbstruct, rbfield); \
new_node->rbaugmented = old_node->rbaugmented; \
old_node->rbaugmented = rbcompute(old_node); \
} \
rbstatic const struct rb_augment_callbacks rbname = { \
rbname ## _propagate, rbname ## _copy, rbname ## _rotate \
};
#define RB_RED 0
#define RB_BLACK 1
#define __rb_parent(pc) ((struct rb_node *)(pc & ~3))
#define __rb_color(pc) ((pc) & 1)
#define __rb_is_black(pc) __rb_color(pc)
#define __rb_is_red(pc) (!__rb_color(pc))
#define rb_color(rb) __rb_color((rb)->__rb_parent_color)
#define rb_is_red(rb) __rb_is_red((rb)->__rb_parent_color)
#define rb_is_black(rb) __rb_is_black((rb)->__rb_parent_color)
static inline void rb_set_parent(struct rb_node *rb, struct rb_node *p)
{
rb->__rb_parent_color = rb_color(rb) | (unsigned long)p;
}
static inline void rb_set_parent_color(struct rb_node *rb,
struct rb_node *p, int color)
{
rb->__rb_parent_color = (unsigned long)p | color;
}
static inline void
__rb_change_child(struct rb_node *old_node, struct rb_node *new_node,
struct rb_node *parent, struct rb_root *root)
{
if (parent) {
if (parent->rb_left == old_node)
parent->rb_left = new_node;
else
parent->rb_right = new_node;
} else
root->rb_node = new_node;
}
extern void __rb_erase_color(struct rb_node *parent, struct rb_root *root,
void (*augment_rotate)(struct rb_node *old_node, struct rb_node *new_node));
static inline struct rb_node *
__rb_erase_augmented(struct rb_node *node, struct rb_root *root,
const struct rb_augment_callbacks *augment)
{
struct rb_node *child = node->rb_right, *tmp = node->rb_left;
struct rb_node *parent, *rebalance;
unsigned long pc;
if (!tmp) {
/*
* Case 1: node to erase has no more than 1 child (easy!)
*
* Note that if there is one child it must be red due to 5)
* and node must be black due to 4). We adjust colors locally
* so as to bypass __rb_erase_color() later on.
*/
pc = node->__rb_parent_color;
parent = __rb_parent(pc);
__rb_change_child(node, child, parent, root);
if (child) {
child->__rb_parent_color = pc;
rebalance = NULL;
} else
rebalance = __rb_is_black(pc) ? parent : NULL;
tmp = parent;
} else if (!child) {
/* Still case 1, but this time the child is node->rb_left */
tmp->__rb_parent_color = pc = node->__rb_parent_color;
parent = __rb_parent(pc);
__rb_change_child(node, tmp, parent, root);
rebalance = NULL;
tmp = parent;
} else {
struct rb_node *successor = child, *child2;
tmp = child->rb_left;
if (!tmp) {
/*
* Case 2: node's successor is its right child
*
* (n) (s)
* / \ / \
* (x) (s) -> (x) (c)
* \
* (c)
*/
parent = successor;
child2 = successor->rb_right;
augment->copy(node, successor);
} else {
/*
* Case 3: node's successor is leftmost under
* node's right child subtree
*
* (n) (s)
* / \ / \
* (x) (y) -> (x) (y)
* / /
* (p) (p)
* / /
* (s) (c)
* \
* (c)
*/
do {
parent = successor;
successor = tmp;
tmp = tmp->rb_left;
} while (tmp);
parent->rb_left = child2 = successor->rb_right;
successor->rb_right = child;
rb_set_parent(child, successor);
augment->copy(node, successor);
augment->propagate(parent, successor);
}
successor->rb_left = tmp = node->rb_left;
rb_set_parent(tmp, successor);
pc = node->__rb_parent_color;
tmp = __rb_parent(pc);
__rb_change_child(node, successor, tmp, root);
if (child2) {
successor->__rb_parent_color = pc;
rb_set_parent_color(child2, parent, RB_BLACK);
rebalance = NULL;
} else {
unsigned long pc2 = successor->__rb_parent_color;
successor->__rb_parent_color = pc;
rebalance = __rb_is_black(pc2) ? parent : NULL;
}
tmp = successor;
}
augment->propagate(tmp, NULL);
return rebalance;
}
static inline void
rb_erase_augmented(struct rb_node *node, struct rb_root *root,
const struct rb_augment_callbacks *augment)
{
struct rb_node *rebalance = __rb_erase_augmented(node, root, augment);
if (rebalance)
__rb_erase_color(rebalance, root, augment->rotate);
}
#endif /* _GENERIC_RBTREE_H */

30
src/lib/cache.c
View File

@@ -6,3 +6,33 @@ struct cache_head {
int hash_size;
pthread_rwlock_t *rwlock;
};
struct cache_head *cache_new(int hashsize, void (*item_free)(struct cache_head *head, struct cache_node *node))
{
return NULL;
}
int cache_add(struct cache_head *head, struct cache_node *node, void *key, int key_len)
{
return 0;
}
int cache_del(struct cache_node *node)
{
return 0;
}
struct cache_node *cache_lookup(struct cache_head *head, void *key, int key_len)
{
return 0;
}
int cache_update(struct cache_head *head, void *key, int key_len)
{
return 0;
}
void cache_free(struct cache_head *head)
{
return
}

507
src/lib/rbtree.c Normal file
View File

@@ -0,0 +1,507 @@
#include "rbtree.h"
#include <stdbool.h>
static inline void rb_set_black(struct rb_node *rb)
{
rb->__rb_parent_color |= RB_BLACK;
}
static inline struct rb_node *rb_red_parent(struct rb_node *red)
{
return (struct rb_node *)red->__rb_parent_color;
}
/*
* Helper function for rotations:
* - old's parent and color get assigned to new
* - old gets assigned new as a parent and 'color' as a color.
*/
static inline void
__rb_rotate_set_parents(struct rb_node *old, struct rb_node *new,
struct rb_root *root, int color)
{
struct rb_node *parent = rb_parent(old);
new->__rb_parent_color = old->__rb_parent_color;
rb_set_parent_color(old, new, color);
__rb_change_child(old, new, parent, root);
}
static inline void
__rb_insert(struct rb_node *node, struct rb_root *root,
void (*augment_rotate)(struct rb_node *old, struct rb_node *new))
{
struct rb_node *parent = rb_red_parent(node), *gparent, *tmp;
while (true) {
/*
* Loop invariant: node is red
*
* If there is a black parent, we are done.
* Otherwise, take some corrective action as we don't
* want a red root or two consecutive red nodes.
*/
if (!parent) {
rb_set_parent_color(node, NULL, RB_BLACK);
break;
} else if (rb_is_black(parent))
break;
gparent = rb_red_parent(parent);
tmp = gparent->rb_right;
if (parent != tmp) { /* parent == gparent->rb_left */
if (tmp && rb_is_red(tmp)) {
/*
* Case 1 - color flips
*
* G g
* / \ / \
* p u --> P U
* / /
* n n
*
* However, since g's parent might be red, and
* 4) does not allow this, we need to recurse
* at g.
*/
rb_set_parent_color(tmp, gparent, RB_BLACK);
rb_set_parent_color(parent, gparent, RB_BLACK);
node = gparent;
parent = rb_parent(node);
rb_set_parent_color(node, parent, RB_RED);
continue;
}
tmp = parent->rb_right;
if (node == tmp) {
/*
* Case 2 - left rotate at parent
*
* G G
* / \ / \
* p U --> n U
* \ /
* n p
*
* This still leaves us in violation of 4), the
* continuation into Case 3 will fix that.
*/
parent->rb_right = tmp = node->rb_left;
node->rb_left = parent;
if (tmp)
rb_set_parent_color(tmp, parent,
RB_BLACK);
rb_set_parent_color(parent, node, RB_RED);
augment_rotate(parent, node);
parent = node;
tmp = node->rb_right;
}
/*
* Case 3 - right rotate at gparent
*
* G P
* / \ / \
* p U --> n g
* / \
* n U
*/
gparent->rb_left = tmp; /* == parent->rb_right */
parent->rb_right = gparent;
if (tmp)
rb_set_parent_color(tmp, gparent, RB_BLACK);
__rb_rotate_set_parents(gparent, parent, root, RB_RED);
augment_rotate(gparent, parent);
break;
} else {
tmp = gparent->rb_left;
if (tmp && rb_is_red(tmp)) {
/* Case 1 - color flips */
rb_set_parent_color(tmp, gparent, RB_BLACK);
rb_set_parent_color(parent, gparent, RB_BLACK);
node = gparent;
parent = rb_parent(node);
rb_set_parent_color(node, parent, RB_RED);
continue;
}
tmp = parent->rb_left;
if (node == tmp) {
/* Case 2 - right rotate at parent */
parent->rb_left = tmp = node->rb_right;
node->rb_right = parent;
if (tmp)
rb_set_parent_color(tmp, parent,
RB_BLACK);
rb_set_parent_color(parent, node, RB_RED);
augment_rotate(parent, node);
parent = node;
tmp = node->rb_left;
}
/* Case 3 - left rotate at gparent */
gparent->rb_right = tmp; /* == parent->rb_left */
parent->rb_left = gparent;
if (tmp)
rb_set_parent_color(tmp, gparent, RB_BLACK);
__rb_rotate_set_parents(gparent, parent, root, RB_RED);
augment_rotate(gparent, parent);
break;
}
}
}
/*
* Inline version for rb_erase() use - we want to be able to inline
* and eliminate the dummy_rotate callback there
*/
static inline void
____rb_erase_color(struct rb_node *parent, struct rb_root *root,
void (*augment_rotate)(struct rb_node *old, struct rb_node *new))
{
struct rb_node *node = NULL, *sibling, *tmp1, *tmp2;
while (true) {
/*
* Loop invariants:
* - node is black (or NULL on first iteration)
* - node is not the root (parent is not NULL)
* - All leaf paths going through parent and node have a
* black node count that is 1 lower than other leaf paths.
*/
sibling = parent->rb_right;
if (node != sibling) { /* node == parent->rb_left */
if (rb_is_red(sibling)) {
/*
* Case 1 - left rotate at parent
*
* P S
* / \ / \
* N s --> p Sr
* / \ / \
* Sl Sr N Sl
*/
parent->rb_right = tmp1 = sibling->rb_left;
sibling->rb_left = parent;
rb_set_parent_color(tmp1, parent, RB_BLACK);
__rb_rotate_set_parents(parent, sibling, root,
RB_RED);
augment_rotate(parent, sibling);
sibling = tmp1;
}
tmp1 = sibling->rb_right;
if (!tmp1 || rb_is_black(tmp1)) {
tmp2 = sibling->rb_left;
if (!tmp2 || rb_is_black(tmp2)) {
/*
* Case 2 - sibling color flip
* (p could be either color here)
*
* (p) (p)
* / \ / \
* N S --> N s
* / \ / \
* Sl Sr Sl Sr
*
* This leaves us violating 5) which
* can be fixed by flipping p to black
* if it was red, or by recursing at p.
* p is red when coming from Case 1.
*/
rb_set_parent_color(sibling, parent,
RB_RED);
if (rb_is_red(parent))
rb_set_black(parent);
else {
node = parent;
parent = rb_parent(node);
if (parent)
continue;
}
break;
}
/*
* Case 3 - right rotate at sibling
* (p could be either color here)
*
* (p) (p)
* / \ / \
* N S --> N Sl
* / \ \
* sl Sr s
* \
* Sr
*/
sibling->rb_left = tmp1 = tmp2->rb_right;
tmp2->rb_right = sibling;
parent->rb_right = tmp2;
if (tmp1)
rb_set_parent_color(tmp1, sibling,
RB_BLACK);
augment_rotate(sibling, tmp2);
tmp1 = sibling;
sibling = tmp2;
}
/*
* Case 4 - left rotate at parent + color flips
* (p and sl could be either color here.
* After rotation, p becomes black, s acquires
* p's color, and sl keeps its color)
*
* (p) (s)
* / \ / \
* N S --> P Sr
* / \ / \
* (sl) sr N (sl)
*/
parent->rb_right = tmp2 = sibling->rb_left;
sibling->rb_left = parent;
rb_set_parent_color(tmp1, sibling, RB_BLACK);
if (tmp2)
rb_set_parent(tmp2, parent);
__rb_rotate_set_parents(parent, sibling, root,
RB_BLACK);
augment_rotate(parent, sibling);
break;
} else {
sibling = parent->rb_left;
if (rb_is_red(sibling)) {
/* Case 1 - right rotate at parent */
parent->rb_left = tmp1 = sibling->rb_right;
sibling->rb_right = parent;
rb_set_parent_color(tmp1, parent, RB_BLACK);
__rb_rotate_set_parents(parent, sibling, root,
RB_RED);
augment_rotate(parent, sibling);
sibling = tmp1;
}
tmp1 = sibling->rb_left;
if (!tmp1 || rb_is_black(tmp1)) {
tmp2 = sibling->rb_right;
if (!tmp2 || rb_is_black(tmp2)) {
/* Case 2 - sibling color flip */
rb_set_parent_color(sibling, parent,
RB_RED);
if (rb_is_red(parent))
rb_set_black(parent);
else {
node = parent;
parent = rb_parent(node);
if (parent)
continue;
}
break;
}
/* Case 3 - right rotate at sibling */
sibling->rb_right = tmp1 = tmp2->rb_left;
tmp2->rb_left = sibling;
parent->rb_left = tmp2;
if (tmp1)
rb_set_parent_color(tmp1, sibling,
RB_BLACK);
augment_rotate(sibling, tmp2);
tmp1 = sibling;
sibling = tmp2;
}
/* Case 4 - left rotate at parent + color flips */
parent->rb_left = tmp2 = sibling->rb_right;
sibling->rb_right = parent;
rb_set_parent_color(tmp1, sibling, RB_BLACK);
if (tmp2)
rb_set_parent(tmp2, parent);
__rb_rotate_set_parents(parent, sibling, root,
RB_BLACK);
augment_rotate(parent, sibling);
break;
}
}
}
/* Non-inline version for rb_erase_augmented() use */
void __rb_erase_color(struct rb_node *parent, struct rb_root *root,
void (*augment_rotate)(struct rb_node *old, struct rb_node *new))
{
____rb_erase_color(parent, root, augment_rotate);
}
/*
* Non-augmented rbtree manipulation functions.
*
* We use dummy augmented callbacks here, and have the compiler optimize them
* out of the rb_insert_color() and rb_erase() function definitions.
*/
static inline void dummy_propagate(struct rb_node *node, struct rb_node *stop) {}
static inline void dummy_copy(struct rb_node *old, struct rb_node *new) {}
static inline void dummy_rotate(struct rb_node *old, struct rb_node *new) {}
static const struct rb_augment_callbacks dummy_callbacks = {
dummy_propagate, dummy_copy, dummy_rotate
};
void rb_insert_color(struct rb_node *node, struct rb_root *root)
{
__rb_insert(node, root, dummy_rotate);
}
void rb_erase(struct rb_node *node, struct rb_root *root)
{
struct rb_node *rebalance;
rebalance = __rb_erase_augmented(node, root, &dummy_callbacks);
if (rebalance)
____rb_erase_color(rebalance, root, dummy_rotate);
}
/*
* Augmented rbtree manipulation functions.
*
* This instantiates the same inline functions as in the non-augmented
* case, but this time with user-defined callbacks.
*/
void __rb_insert_augmented(struct rb_node *node, struct rb_root *root,
void (*augment_rotate)(struct rb_node *old, struct rb_node *new))
{
__rb_insert(node, root, augment_rotate);
}
/*
* This function returns the first node (in sort order) of the tree.
*/
struct rb_node *rb_first(const struct rb_root *root)
{
struct rb_node *n;
n = root->rb_node;
if (!n)
return NULL;
while (n->rb_left)
n = n->rb_left;
return n;
}
struct rb_node *rb_last(const struct rb_root *root)
{
struct rb_node *n;
n = root->rb_node;
if (!n)
return NULL;
while (n->rb_right)
n = n->rb_right;
return n;
}
struct rb_node *rb_next(const struct rb_node *node)
{
struct rb_node *parent;
if (RB_EMPTY_NODE(node))
return NULL;
/*
* If we have a right-hand child, go down and then left as far
* as we can.
*/
if (node->rb_right) {
node = node->rb_right;
while (node->rb_left)
node=node->rb_left;
return (struct rb_node *)node;
}
/*
* No right-hand children. Everything down and left is smaller than us,
* so any 'next' node must be in the general direction of our parent.
* Go up the tree; any time the ancestor is a right-hand child of its
* parent, keep going up. First time it's a left-hand child of its
* parent, said parent is our 'next' node.
*/
while ((parent = rb_parent(node)) && node == parent->rb_right)
node = parent;
return parent;
}
struct rb_node *rb_prev(const struct rb_node *node)
{
struct rb_node *parent;
if (RB_EMPTY_NODE(node))
return NULL;
/*
* If we have a left-hand child, go down and then right as far
* as we can.
*/
if (node->rb_left) {
node = node->rb_left;
while (node->rb_right)
node=node->rb_right;
return (struct rb_node *)node;
}
/*
* No left-hand children. Go up till we find an ancestor which
* is a right-hand child of its parent.
*/
while ((parent = rb_parent(node)) && node == parent->rb_left)
node = parent;
return parent;
}
void rb_replace_node(struct rb_node *victim, struct rb_node *new,
struct rb_root *root)
{
struct rb_node *parent = rb_parent(victim);
/* Set the surrounding nodes to point to the replacement */
__rb_change_child(victim, new, parent, root);
if (victim->rb_left)
rb_set_parent(victim->rb_left, new);
if (victim->rb_right)
rb_set_parent(victim->rb_right, new);
/* Copy the pointers/colour from the victim to the replacement */
*new = *victim;
}
static struct rb_node *rb_left_deepest_node(const struct rb_node *node)
{
for (;;) {
if (node->rb_left)
node = node->rb_left;
else if (node->rb_right)
node = node->rb_right;
else
return (struct rb_node *)node;
}
}
struct rb_node *rb_next_postorder(const struct rb_node *node)
{
const struct rb_node *parent;
if (!node)
return NULL;
parent = rb_parent(node);
/* If we're sitting on node, we've already seen our children */
if (parent && node == parent->rb_left && parent->rb_right) {
/* If we are the parent's left node, go to the parent's right
* node then all the way down to the left */
return rb_left_deepest_node(parent->rb_right);
} else
/* Otherwise we are the parent's right node, and the parent
* should be next */
return (struct rb_node *)parent;
}
struct rb_node *rb_first_postorder(const struct rb_root *root)
{
if (!root->rb_node)
return NULL;
return rb_left_deepest_node(root->rb_node);
}

52
src/smartdns.c
View File

@@ -23,6 +23,7 @@
#include "fast_ping.h"
#include "hashtable.h"
#include "list.h"
#include "rbtree.h"
#include "tlog.h"
#include "util.h"
#include <errno.h>
@@ -246,6 +247,57 @@ void sig_handle(int sig)
_exit(0);
}
#if 0
struct data_rbtree {
struct rb_node list;
int value;
};
int rbtree_test()
{
struct rb_root root = RB_ROOT;
struct rb_node *n;
int i;
for (i = 0; i < 10; i++) {
struct data_rbtree *r = malloc(sizeof(struct data_rbtree));
struct rb_node **new = &root.rb_node, *parent = NULL;
r->value = i;
while (*new) {
parent = *new;
if (i < rb_entry(parent, struct data_rbtree, list)->value)
new = &parent->rb_left;
else
new = &parent->rb_right;
}
rb_link_node(&r->list, parent, new);
rb_insert_color(&r->list, &root);
}
n = root.rb_node;
int num = 5;
while (n) {
struct data_rbtree *r = rb_entry(n, struct data_rbtree, list);
if (r->value > num) {
n = n->rb_left;
} else if (r->value < num) {
n = n->rb_right;
} else {
printf("n = %d\n", r->value);
break;
}
}
struct rb_node *node;
for (node = rb_first(&root); node; node = rb_next(node))
printf("V = %d\n", rb_entry(node, struct data_rbtree, list)->value);
return 0;
}
#endif
int main(int argc, char *argv[])
{
int ret;