[backfire] merge r26930
[openwrt-10.03/.git] / package / base-files / files / usr / lib / common.awk
1 # Copyright (C) 2006 OpenWrt.org
2
3 function bitcount(c) {
4         c=and(rshift(c, 1),0x55555555)+and(c,0x55555555)
5         c=and(rshift(c, 2),0x33333333)+and(c,0x33333333)
6         c=and(rshift(c, 4),0x0f0f0f0f)+and(c,0x0f0f0f0f)
7         c=and(rshift(c, 8),0x00ff00ff)+and(c,0x00ff00ff)
8         c=and(rshift(c,16),0x0000ffff)+and(c,0x0000ffff)
9         return c
10 }
11
12 function validate_netmask(nm) {
13         return and(-nm,compl(nm))
14 }
15
16 function ip2int(ip) {
17         for (ret=0,n=split(ip,a,"\."),x=1;x<=n;x++) ret=or(lshift(ret,8),a[x]) 
18         return ret
19 }
20
21 function int2ip(ip,ret,x) {
22         ret=and(ip,255)
23         ip=rshift(ip,8)
24         for(;x<3;ret=and(ip,255)"."ret,ip=rshift(ip,8),x++);
25         return ret
26 }