annotate src/core/ngx_murmurhash.c @ 4404:840f3e768ef8

Fixed division by zero exception in ngx_hash_init(). The ngx_hash_init() function did not expect call with zero elements count, which caused FPE error on configs with an empty "types" block in http context and "types_hash_max_size" > 10000. Example configuration to reproduce: events { } http { types_hash_max_size 10001; types {} server {} }
author Valentin Bartenev <vbart@nginx.com>
date Mon, 16 Jan 2012 12:42:07 +0000
parents 203eb026ec07
children f38647c651a8
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
3891
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
1
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
2 /*
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
3 * Copyright (C) Austin Appleby
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
4 */
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
5
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
6
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
7 #include <ngx_config.h>
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
8 #include <ngx_core.h>
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
9
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
10
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
11 uint32_t
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
12 ngx_murmur_hash2(u_char *data, size_t len)
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
13 {
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
14 uint32_t h, k;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
15
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
16 h = 0 ^ len;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
17
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
18 while (len >= 4) {
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
19 k = data[0];
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
20 k |= data[1] << 8;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
21 k |= data[2] << 16;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
22 k |= data[3] << 24;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
23
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
24 k *= 0x5bd1e995;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
25 k ^= k >> 24;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
26 k *= 0x5bd1e995;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
27
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
28 h *= 0x5bd1e995;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
29 h ^= k;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
30
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
31 data += 4;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
32 len -= 4;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
33 }
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
34
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
35 switch (len) {
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
36 case 3:
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
37 h ^= data[2] << 16;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
38 case 2:
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
39 h ^= data[1] << 8;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
40 case 1:
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
41 h ^= data[0];
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
42 h *= 0x5bd1e995;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
43 }
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
44
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
45 h ^= h >> 13;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
46 h *= 0x5bd1e995;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
47 h ^= h >> 15;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
48
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
49 return h;
203eb026ec07 ngx_murmur_hash2()
Igor Sysoev <igor@sysoev.ru>
parents:
diff changeset
50 }