1 files changed, 74 insertions, 0 deletions
diff --git a/include/dnsjit/filter/copy.lua b/include/dnsjit/filter/copy.lua
new file mode 100644
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+++ b/include/dnsjit/filter/copy.lua
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+-- Copyright (c) 2019 CZ.NIC, z.s.p.o.
+-- All rights reserved.
+--
+-- This file is part of dnsjit.
+--
+-- dnsjit is free software: you can redistribute it and/or modify
+-- it under the terms of the GNU General Public License as published by
+-- the Free Software Foundation, either version 3 of the License, or
+-- (at your option) any later version.
+--
+-- dnsjit is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+-- GNU General Public License for more details.
+--
+-- You should have received a copy of the GNU General Public License
+-- along with dnsjit.  If not, see <http://www.gnu.org/licenses/>.
+
+-- dnsjit.filter.copy
+-- Creates a copy of an object chain with selected object types.
+--   local copy = require("dnsjit.filter.copy").new()
+--   local object = require("dnsjit.core.objects")
+--   copy:obj_type(object.PAYLOAD)
+--   copy:obj_type(object.IP6)
+--   channel:receiver(copy)
+--
+-- Filter to create a copy of the object chain with selected object types.
+-- The user is responsible for manually freeing the created object chain.
+module(...,package.seeall)
+
+require("dnsjit.filter.copy_h")
+local object = require("dnsjit.core.object")
+local ffi = require("ffi")
+local C = ffi.C
+
+local t_name = "filter_copy_t"
+local filter_copy_t = ffi.typeof(t_name)
+local Copy = {}
+
+-- Create a new Copy filter.
+function Copy.new()
+    local self = {
+        obj = filter_copy_t(),
+    }
+    C.filter_copy_init(self.obj)
+    ffi.gc(self.obj, C.filter_copy_destroy)
+    return setmetatable(self, { __index = Copy })
+end
+
+-- Return the Log object to control logging of this instance or module.
+function Copy:log()
+    if self == nil then
+        return C.filter_copy_log()
+    end
+    return self.obj._log
+end
+
+-- Set the object type to be copied. Can be called multiple times to copy
+-- multiple object types from the object chain.
+function Copy:obj_type(obj_type)
+    C.filter_copy_set(self.obj, obj_type)
+end
+
+-- Return the C functions and context for receiving objects.
+function Copy:receive()
+    return C.filter_copy_receiver(self.obj), self.obj
+end
+
+-- Set the receiver to pass objects to.
+function Copy:receiver(o)
+    self.obj.recv, self.obj.recv_ctx = o:receive()
+end
+
+return Copy