base-files: ipcalc.sh: support bit length as netmask parameter
[openwrt.git] / package / base-files / files / bin / ipcalc.sh
index 318980e..5d5eac3 100755 (executable)
@@ -1,29 +1,68 @@
 #!/bin/sh
 
-awk -f /usr/lib/common.awk -f - $* <<EOF
+awk -f - $* <<EOF
+function bitcount(c) {
+       c=and(rshift(c, 1),0x55555555)+and(c,0x55555555)
+       c=and(rshift(c, 2),0x33333333)+and(c,0x33333333)
+       c=and(rshift(c, 4),0x0f0f0f0f)+and(c,0x0f0f0f0f)
+       c=and(rshift(c, 8),0x00ff00ff)+and(c,0x00ff00ff)
+       c=and(rshift(c,16),0x0000ffff)+and(c,0x0000ffff)
+       return c
+}
+
+function ip2int(ip) {
+       for (ret=0,n=split(ip,a,"\."),x=1;x<=n;x++) ret=or(lshift(ret,8),a[x])
+       return ret
+}
+
+function int2ip(ip,ret,x) {
+       ret=and(ip,255)
+       ip=rshift(ip,8)
+       for(;x<3;ret=and(ip,255)"."ret,ip=rshift(ip,8),x++);
+       return ret
+}
+
+function compl32(v) {
+       ret=xor(v, 0xffffffff)
+       return ret
+}
+
 BEGIN {
-       ipaddr=ip2int(ARGV[1])
-       netmask=ip2int(ARGV[2])
+       slpos=index(ARGV[1],"/")
+       if (slpos == 0) {
+               ipaddr=ip2int(ARGV[1])
+               dotpos=index(ARGV[2],".")
+               if (dotpos == 0)
+                       netmask=compl32(2**(32-int(ARGV[2]))-1)
+               else
+                       netmask=ip2int(ARGV[2])
+       } else {
+               ipaddr=ip2int(substr(ARGV[1],0,slpos-1))
+               netmask=compl32(2**(32-int(substr(ARGV[1],slpos+1)))-1)
+               ARGV[4]=ARGV[3]
+               ARGV[3]=ARGV[2]
+       }
+
        network=and(ipaddr,netmask)
-       broadcast=or(network,compl(netmask))
-       
-       start=or(network,and(ip2int(ARGV[3]),compl(netmask)))
+       broadcast=or(network,compl32(netmask))
+
+       start=or(network,and(ip2int(ARGV[3]),compl32(netmask)))
        limit=network+1
        if (start<limit) start=limit
-       
+
        end=start+ARGV[4]
-       limit=or(network,compl(netmask))-1
+       limit=or(network,compl32(netmask))-1
        if (end>limit) end=limit
 
        print "IP="int2ip(ipaddr)
        print "NETMASK="int2ip(netmask)
        print "BROADCAST="int2ip(broadcast)
        print "NETWORK="int2ip(network)
-       print "PREFIX="32-bitcount(compl(netmask))
-       
+       print "PREFIX="32-bitcount(compl32(netmask))
+
        # range calculations:
        # ipcalc <ip> <netmask> <start> <num>
-       
+
        if (ARGC > 3) {
                print "START="int2ip(start)
                print "END="int2ip(end)