first commit

node_modules/netmask/lib/netmask.coffee

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+long2ip = (long) ->
+    a = (long & (0xff << 24)) >>> 24;
+    b = (long & (0xff << 16)) >>> 16;
+    c = (long & (0xff << 8)) >>> 8;
+    d = long & 0xff;
+    return [a, b, c, d].join('.')
+
+ip2long = (ip) ->
+    b = []
+    for i in [0..3]
+        if ip.length == 0
+            break
+        if i > 0
+            if ip[0] != '.'
+                throw new Error('Invalid IP')
+            ip = ip.substring(1)
+        [n, c] = atob(ip)
+        ip = ip.substring(c)
+        b.push(n)
+    if ip.length != 0
+        throw new Error('Invalid IP')
+    switch b.length
+        when 1
+            # Long input notation
+            if b[0] > 0xFFFFFFFF
+                throw new Error('Invalid IP')
+            return b[0] >>> 0
+        when 2
+            # Class A notation
+            if b[0] > 0xFF or b[1] > 0xFFFFFF
+                throw new Error('Invalid IP')
+            return (b[0] << 24 | b[1]) >>> 0
+        when 3
+            # Class B notation
+            if b[0] > 0xFF or b[1] > 0xFF or b[2] > 0xFFFF
+                throw new Error('Invalid IP')
+            return (b[0] << 24 | b[1] << 16 | b[2]) >>> 0
+        when 4
+            # Dotted quad notation 
+            if b[0] > 0xFF or b[1] > 0xFF or b[2] > 0xFF or b[3] > 0xFF
+                throw new Error('Invalid IP')
+            return (b[0] << 24 | b[1] << 16 | b[2] << 8 | b[3]) >>> 0
+        else
+            throw new Error('Invalid IP')
+
+chr = (b) ->
+    return b.charCodeAt(0)
+
+chr0 = chr('0')
+chra = chr('a')
+chrA = chr('A')
+
+atob = (s) ->
+    n = 0
+    base = 10
+    dmax = '9'
+    i = 0
+    if s.length > 1 and s[i] == '0'
+        if s[i+1] == 'x' or s[i+1] == 'X'
+            i += 2
+            base = 16
+        else if '0' <= s[i+1] and s[i+1] <= '9'
+            i++
+            base = 8
+            dmax = '7'
+    start = i
+    while i < s.length
+        if '0' <= s[i] and s[i] <= dmax
+            n = (n*base + (chr(s[i])-chr0)) >>> 0
+        else if base == 16
+            if 'a' <= s[i] and s[i] <= 'f'
+                n = (n*base + (10+chr(s[i])-chra)) >>> 0
+            else if 'A' <= s[i] and s[i] <= 'F'
+                n = (n*base + (10+chr(s[i])-chrA)) >>> 0
+            else
+                break
+        else
+            break
+        if n > 0xFFFFFFFF
+            throw new Error('too large')
+        i++
+    if i == start
+        throw new Error('empty octet')
+    return [n, i]
+
+class Netmask
+    constructor: (net, mask) ->
+        throw new Error("Missing `net' parameter") unless typeof net is 'string'
+        unless mask
+            # try to find the mask in the net (i.e.: 1.2.3.4/24 or 1.2.3.4/255.255.255.0)
+            [net, mask] = net.split('/', 2)
+        unless mask
+            mask = 32
+        if typeof mask is 'string' and mask.indexOf('.') > -1
+            # Compute bitmask, the netmask as a number of bits in the network portion of the address for this block (eg.: 24)
+            try
+                @maskLong = ip2long(mask)
+            catch error
+                throw new Error("Invalid mask: #{mask}")
+            for i in [32..0]
+                if @maskLong == (0xffffffff << (32 - i)) >>> 0
+                    @bitmask = i
+                    break
+        else if mask or mask == 0
+            # The mask was passed as bitmask, compute the mask as long from it
+            @bitmask = parseInt(mask, 10)
+            @maskLong = 0
+            if @bitmask > 0
+                @maskLong = (0xffffffff << (32 - @bitmask)) >>> 0
+        else
+            throw new Error("Invalid mask: empty")
+
+        try
+            @netLong = (ip2long(net) & @maskLong) >>> 0
+        catch error
+            throw new Error("Invalid net address: #{net}")
+
+        throw new Error("Invalid mask for ip4: #{mask}") unless @bitmask <= 32
+
+        # The number of IP address in the block (eg.: 254)
+        @size = Math.pow(2, 32 - @bitmask)
+        # The address of the network block as a string (eg.: 216.240.32.0)
+        @base = long2ip(@netLong)
+        # The netmask as a string (eg.: 255.255.255.0)
+        @mask = long2ip(@maskLong)
+        # The host mask, the opposite of the netmask (eg.: 0.0.0.255)
+        @hostmask = long2ip(~@maskLong)
+        # The first usable address of the block
+        @first = if @bitmask <= 30 then long2ip(@netLong + 1) else @base
+        # The last  usable address of the block
+        @last = if @bitmask <= 30 then long2ip(@netLong + @size - 2) else long2ip(@netLong + @size - 1)
+        # The block's broadcast address: the last address of the block (eg.: 192.168.1.255)
+        @broadcast = if @bitmask <= 30 then long2ip(@netLong + @size - 1)
+
+    # Returns true if the given ip or netmask is contained in the block
+    contains: (ip) ->
+        if typeof ip is 'string' and (ip.indexOf('/') > 0 or ip.split('.').length isnt 4)
+            ip = new Netmask(ip)
+
+        if ip instanceof Netmask
+            return @contains(ip.base) and @contains((ip.broadcast || ip.last))
+        else
+            return (ip2long(ip) & @maskLong) >>> 0 == ((@netLong & @maskLong)) >>> 0
+
+    # Returns the Netmask object for the block which follow this one
+    next: (count=1) ->
+        return new Netmask(long2ip(@netLong + (@size * count)), @mask)
+
+    forEach: (fn) ->
+        # this implementation is not idiomatic but avoids large memory allocations (2 arrays, one for range and one for the results) in cases when then netmask is large
+        long = ip2long(@first)
+        lastLong = ip2long(@last)
+        index = 0
+        while long <= lastLong
+          fn long2ip(long), long, index
+          index++
+          long++
+        return
+
+    # Returns the complete netmask formatted as `base/bitmask`
+    toString: ->
+        return @base + "/" + @bitmask
+
+
+exports.ip2long = ip2long
+exports.long2ip = long2ip
+exports.Netmask = Netmask