1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
|
/*
* Filters: utility functions
*
* Copyright 1998 Pavel Machek <pavel@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/signal.h>
#include <setjmp.h>
#include "nest/bird.h"
#include "lib/lists.h"
#include "lib/resource.h"
#include "lib/socket.h"
#include "nest/route.h"
#include "nest/protocol.h"
#include "nest/iface.h"
#include "conf/conf.h"
#include "filter/filter.h"
/* Finds n-th item in list linked by right. Trashes pointers in right. */
static struct f_tree *
find_nth(struct f_tree *from, int nth)
{
struct f_tree *pivot;
int lcount = 0, rcount = 0;
struct f_tree *left, *right, *next;
pivot = from;
left = right = NULL;
next = from->right;
while (from = next) {
next = from->right;
if (val_compare(pivot->from, from->from)==1) {
from->right = left;
left = from;
lcount++;
} else {
from->right = right;
right = from;
rcount++;
}
}
if (lcount == nth)
return pivot;
if (lcount < nth)
return find_nth(right, nth-lcount-1);
return find_nth(left, nth);
}
/* Gets list linked by left, finds its median, trashes pointers in right */
static struct f_tree *
find_median(struct f_tree *from)
{
struct f_tree *t = from;
int cnt = 0;
if (!from)
return NULL;
do {
t->right = t->left;
cnt++;
} while (t = t->left);
return find_nth(from, cnt/2);
}
struct f_tree *
find_tree(struct f_tree *t, struct f_val val)
{
if (!t)
return NULL;
if ((val_compare(t->from, val) != 1) &&
(val_compare(t->to, val) != -1))
return t;
if (val_compare(t->from, val) == -1)
return find_tree(t->right, val);
else
return find_tree(t->left, val);
}
/* Gets list linked by left */
struct f_tree *
build_tree(struct f_tree *from)
{
struct f_tree *median, *t = from, *next, *left = NULL, *right = NULL;
median = find_median(from);
if (!median)
return NULL;
do {
next = t->left;
if (t == median)
continue;
if (val_compare(median->from, t->from)==1) {
t->left = left;
left = t;
} else {
t->left = right;
right = t;
}
} while(t = next);
median->left = build_tree(left);
median->right = build_tree(right);
return median;
}
struct f_tree *
f_new_tree(void)
{
struct f_tree * ret;
ret = cfg_alloc(sizeof(struct f_tree));
ret->left = ret->right = NULL;
ret->from.type = ret->to.type = T_VOID;
ret->from.val.i = ret->to.val.i = 0;
ret->data = NULL;
return ret;
}
int
same_tree(struct f_tree *t1, struct f_tree *t2)
{
if ((!!t1) != (!!t2))
return 0;
if (!t1)
return 1;
if (val_compare(t1->from, t2->from))
return 0;
if (val_compare(t1->to, t2->to))
return 0;
if (!same_tree(t1->left, t2->left))
return 0;
if (!same_tree(t1->right, t2->right))
return 0;
if (!i_same(t1->data, t2->data))
return 0;
return 1;
}
|
