1 files changed, 93 insertions, 0 deletions
diff --git a/include/dnsjit/lib/trie/iter.lua b/include/dnsjit/lib/trie/iter.lua
new file mode 100644
index 0000000..520cc7b
--- /dev/null
+++ b/include/dnsjit/lib/trie/iter.lua
@@ -0,0 +1,93 @@
+-- Copyright (c) 2020, 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.lib.trie.iter
+-- Iterator of the trie.
+-- .SS Iterate over all trie's key-value pairs
+--   local trie = require("dnsjit.lib.trie").new("uint64_t")
+--   local iter = trie:iter()
+--   local node = iter:node()
+--   while node ~= nil do
+--       local key = node:key()
+--       local value = tonumber(node:get())
+--       print(key..": "..value)
+--       iter:next()
+--       node = iter:node()
+--   end
+--
+-- Beware that iterator is only valid as long as the trie's key-set
+-- remains unchanged.
+module(...,package.seeall)
+
+require("dnsjit.lib.trie_h")
+local ffi = require("ffi")
+local C = ffi.C
+local log = require("dnsjit.core.log")
+local module_log = log.new("lib.trie.iter")
+local TrieNode = require("dnsjit.lib.trie.node")
+
+TrieIter = {}
+
+-- Create a new iterator pointing to the first element (if any).
+function TrieIter.new(trie)
+    local self = setmetatable({
+        obj = C.trie_it_begin(trie.obj),
+        _trie = trie,
+        _log = log.new("lib.trie.iter", module_log),
+    }, { __index = TrieIter })
+
+    ffi.gc(self.obj, C.trie_it_free)
+
+    return self
+end
+
+-- Return the Log object to control logging of this instance or module.
+function TrieIter:log()
+    if self == nil then
+        return module_log
+    end
+    return self._log
+end
+
+-- Return the node pointer to by the iterator.
+-- Returns nil when iterator has gone past the last element.
+function TrieIter:node()
+    if C.trie_it_finished(self.obj) then
+        return nil
+    end
+
+    local keylen_ptr = ffi.new("size_t[1]")
+    local key = C.trie_it_key(self.obj, keylen_ptr)
+    local keylen = tonumber(keylen_ptr[0])
+
+    local val = C.trie_it_val(self.obj)
+    return TrieNode.new(self._trie, val, key, keylen)
+end
+
+-- Advance the iterator to the next element.
+--
+-- Iteration is in ascending lexicographical order.
+-- Empty string would be considered as the very first.
+--
+-- You may not use this function if the trie's key-set has been modified during the lifetime of the iterator (modifying only values is OK).
+function TrieIter:next()
+    C.trie_it_next(self.obj)
+end
+
+-- dnsjit.lib.trie (3), dnsjit.lib.trie.node (3)
+return TrieIter