1 files changed, 93 insertions, 0 deletions
diff --git a/daemon/lua/zonefile.lua b/daemon/lua/zonefile.lua
new file mode 100644
index 0000000..8ea3a08
--- /dev/null
+++ b/daemon/lua/zonefile.lua
@@ -0,0 +1,93 @@
+-- SPDX-License-Identifier: GPL-3.0-or-later
+
+-- LuaJIT ffi bindings for zscanner, a DNS zone parser.
+-- Author: Marek Vavrusa <marek.vavrusa@nic.cz>
+
+local ffi = require('ffi')
+local libzscanner = ffi.load(libzscanner_SONAME)
+
+-- Wrap scanner context
+local zs_scanner_t = ffi.typeof('zs_scanner_t')
+ffi.metatype( zs_scanner_t, {
+	__gc = function(zs) return libzscanner.zs_deinit(zs) end,
+	__new = function(ct, origin, class, ttl)
+		if not class then class = 1 end
+		if not ttl then ttl = 3600 end
+		local parser = ffi.new(ct)
+		libzscanner.zs_init(parser, origin, class, ttl)
+		return parser
+	end,
+	__index = {
+		open = function (zs, file)
+			assert(ffi.istype(zs, zs_scanner_t))
+			local ret = libzscanner.zs_set_input_file(zs, file)
+			if ret ~= 0 then return false, zs:strerr() end
+			return true
+		end,
+		parse = function(zs, input)
+			assert(ffi.istype(zs, zs_scanner_t))
+			if input ~= nil then libzscanner.zs_set_input_string(zs, input, #input) end
+			local ret = libzscanner.zs_parse_record(zs)
+			-- Return current state only when parsed correctly, otherwise return error
+			if ret == 0 and zs.state ~= "ZS_STATE_ERROR" then
+				return zs.state == "ZS_STATE_DATA"
+			else
+				return false, zs:strerr()
+			end
+		end,
+		current_rr = function(zs)
+			assert(ffi.istype(zs, zs_scanner_t))
+			return {
+				owner = ffi.string(zs.r_owner, zs.r_owner_length),
+				ttl = tonumber(zs.r_ttl),
+				class = tonumber(zs.r_class),
+				type = tonumber(zs.r_type),
+				rdata = ffi.string(zs.r_data, zs.r_data_length),
+				comment = zs:current_comment(),
+			}
+		end,
+		strerr = function(zs)
+			assert(ffi.istype(zs, zs_scanner_t))
+			return ffi.string(libzscanner.zs_strerror(zs.error.code))
+		end,
+		current_comment = function(zs)
+			if zs.buffer_length > 0 then
+				return ffi.string(zs.buffer, zs.buffer_length - 1)
+			else
+				return nil
+			end
+		end
+	},
+})
+
+-- Module API
+local rrparser = {
+	new = zs_scanner_t,
+
+	-- Parse a file into a list of RRs
+	file = function (path)
+		local zs = zs_scanner_t()
+		local ok, err = zs:open(path)
+		if not ok then
+			return ok, err
+		end
+		local results = {}
+		while zs:parse() do
+			table.insert(results, zs:current_rr())
+		end
+		return results
+	end,
+
+	-- Parse a string into a list of RRs.
+	string = function (input)
+		local zs = zs_scanner_t()
+		local results = {}
+		local ok = zs:parse(input)
+		while ok do
+			table.insert(results, zs:current_rr())
+			ok = zs:parse()
+		end
+		return results
+	end,
+}
+return rrparser