IP (version 0.1)

Bitwise-methods: Bitwise operations

Description

Methods for IP bitwise operations !e1 e1 & e2 e1 | e2 e1 %>>% e2 e1 %<<% e2 e1 ^ e2 ip.xor(e1 , e2 ) ipv4.netmask(n) ipv6.netmask(n) ipv4.hostmask(n) ipv6.hostmask(n)

Arguments

e1

an object of either an 'IPv4', 'IPv6' or 'IP' class

e2

an object of either an 'IPv4', 'IPv6' or 'IP' class except for shifts where e2 is like 'n'

n

an integer in the range (0,32) for IPv4 or in the (0,128) for IPv6 for masking methods

Value

an object of either an 'IPv4', 'IPv6' or 'IP' class

Details

The &, | and ! operators behave differently from their base R counterparts in that they perform bitwise operation much like in the C language.

• & : bitwise AND

• | : bitwise non exclusive OR

• ! : bitwise NOT

ip.xor() provides a faster alternative to base xor().

%>>% and %<<% perform left (binary division) and right shift (binary multiplication) respectively.

The *.netmask() and *.hostmask() functions return the net and host mask of specified length n.

Examples

# NOT RUN {
##
private.network <- ipv4r("192.0.0.0/16")
##
(mask.len <- ceiling(log2(ip.range(private.network))))
##
ip <- ipv4("192.168.1.1") 
##
(netmask <- ipv4.netmask(mask.len))
##
ip & netmask
##
(hostmask <- ipv4.hostmask(mask.len))
##
ip & hostmask
##
((ip & netmask) | (ip & hostmask) )==ip
## 2 complement
((!ip) + 1L)==-ip
##
ipv4('0.0.0.2') %>>% 1L
##
ipv4('0.0.0.2') %<<% 1L
##
## branchless swap
##
ipv4.ifelse <- function(test, yes, no){
  ## 
  if( ( class(yes)!='IPv4' ) | ( class(no)!='IPv4' ) ){
    stop('both arguments should be of class IPv4')
  }
  ##
  ip.xor(
    no
    , ip.xor(
      no, yes
    ) & -(ipv4(test)) ## mask
  )
}
##
x <- ipv4('192.168.0.0') + 1:5
## recycling without warning (yet)
y <- x + c(1,-1)
##
test <- x < y
##
data.frame(
  x, y, test, res= ipv4.ifelse(test , x,y)
)
##
##
##
ip6 <- ipv6("2606:2800:220:1:248:1893:25c8:1946")
## Unicast addresses global routing prefix
ip6 & ipv6.netmask(48)
## Subnet ID
ip6 & (ipv6.hostmask(128-16) %<<% 64L)
## Interface ID 
ip6 & ipv6.hostmask(64)
# }