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| author | Asbjørn Sloth Tønnesen <ast@2e8.dk> | 2019-07-20 18:19:38 +0000 |
|---|---|---|
| committer | Asbjørn Sloth Tønnesen <ast@2e8.dk> | 2019-07-20 18:19:38 +0000 |
| commit | 9edfd0002bea4d591cb363be536c652ef3f16079 (patch) | |
| tree | ac6574c09294672d5cbe79eae186588934df5d8f /lua/inet/core.lua | |
| parent | d42329c948cafec31250c8cdba028d116a76a709 (diff) | |
| download | lua-inet-9edfd0002bea4d591cb363be536c652ef3f16079.tar.gz lua-inet-9edfd0002bea4d591cb363be536c652ef3f16079.tar.xz lua-inet-9edfd0002bea4d591cb363be536c652ef3f16079.zip | |
add inet:subnets()
Signed-off-by: Asbjørn Sloth Tønnesen <ast@2e8.dk>
Diffstat (limited to 'lua/inet/core.lua')
| -rw-r--r-- | lua/inet/core.lua | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/lua/inet/core.lua b/lua/inet/core.lua index f1c7c49..15dd0f9 100644 --- a/lua/inet/core.lua +++ b/lua/inet/core.lua @@ -6,6 +6,7 @@ local format = string.format local floor = math.floor local min = math.min local max = math.max +local pow = math.pow local insert = table.insert local lshift = bit32.lshift @@ -55,6 +56,16 @@ end inet4.__len = inet.__len inet6.__len = inet.__len +function inet:subnets(n) + if type(n) ~= 'number' then return nil, 'n must be a number' end + local hostmask = is_inet6(self) and 128 or 32 + if n < 0 or n > hostmask then return nil, 'invalid mask given' end + local mask = self.mask + local bits = n - mask + local subnets = pow(2, bits) + return subnets +end + function inet:family() local mt = assert(getmetatable(self)) return assert(mt2fam[mt]) @@ -329,7 +340,7 @@ function inet4:__sub(n) end function inet4:__mul(n) - local new = self.bip + (n * math.pow(2, 32 - self.mask)) + local new = self.bip + (n * pow(2, 32 - self.mask)) return new_inet4(new, self.mask) end |