cache.clear: clearing root clears everything, not only the root zone

Problem was caused by our lookup format where only the root zone starts
with \0 and all other zones start differently. This caused
cache_match('.') to match only data from root zone.

.luacheckrc

@@ -79,3 +79,4 @@ files['daemon/lua/kres-gen.lua'].ignore = {'631'} -- Allow overly long lines
 files['scripts'].ignore = {'111', '112', '113'}
 files['tests'].ignore = {'111', '112', '113'}
 files['modules/**/*.test.lua'].ignore = {'111', '112', '113', '121', '122'}
+files['daemon/**/*.test.lua'].ignore = {'111', '112', '113', '121', '122'}

daemon/cache.test/clear.test.lua

@@ -26,9 +26,9 @@ assert(net.interfaces() ~= nil)
 -- Self-checks on loaded stuff
 assert(#modules.list() > 0)
 -- Self-check timers
-ev = event.recurrent(1 * sec, function (ev) return 1 end)
+ev = event.recurrent(1 * sec, function () return 1 end)
 event.cancel(ev)
-ev = event.after(0, function (ev) return 1 end)
+ev = event.after(0, function () return 1 end)
 
 
 -- import fake root zone
@@ -61,8 +61,8 @@ local function import_zone()
 	worker.sleep(0.2)  -- zimport is delayed by 100 ms from function call
 	-- sanity checks - cache must be filled in
 	ok(cache.count() > 0, 'cache is not empty after import')
-	check_answer('root apex is cache',
-	  	     '.', kres.type.NS, kres.rcode.NOERROR)
+	check_answer('root apex is in cache',
+                     '.', kres.type.NS, kres.rcode.NOERROR)
 	check_answer('deep subdomain is in cache',
 		     'a.b.subtree1.', kres.type.AAAA, kres.rcode.NOERROR)
 
@@ -120,23 +120,22 @@ end
 
 local function test_callback()
 	local test_name = '20r.subtree2.'
-	local test_maxcount = 1
 	local test_exactname = true
 	local test_rrtype = nil
-	local test_maxcount = 1
+	local test_chunksize = 1
 	local test_prev_state = { works = true }
 	local function check_callback(name, exact_name, rr_type, chunk_size, callback, prev_state, errors)
 		is(errors.count, 1, 'callback received correct # of removed records')
 		is(test_name, name, 'callback received subtree name')
 		is(test_exactname, exact_name, 'callback received exact_name')
-		is(test_rrtype, rrtype, 'callback received rr_type')
-		is(test_chunksize, chunksize, 'callback received maxcount')
+		is(test_rrtype, rr_type, 'callback received rr_type')
+		is(test_chunksize, chunk_size, 'callback received chunk_size')
 		is(check_callback, callback, 'callback received reference to itself')
 		is(type(errors), 'table', 'callback received table of errors')
 		same(test_prev_state, prev_state, 'callback received previous state')
 		return 666
 	end
-	same(cache.clear(test_name, test_exactname, test_rrtype, test_maxcount, check_callback, test_prev_state),
+	same(cache.clear(test_name, test_exactname, test_rrtype, test_chunksize, check_callback, test_prev_state),
 	     666, 'first callback return value is passed to cache.clear() caller')
 	local cnt_before_wait = cache.count()
 	worker.sleep(0.2)
@@ -173,6 +172,13 @@ local function test_apex()
 		     'a.b.subtree1.', kres.type.NULL, kres.rcode.SERVFAIL)
 end
 
+local function test_root()
+	local prev_count = cache.count()
+	res = cache.clear('.')
+	is(res.count, prev_count, 'full clear reports correct number of entries')
+	is(cache.count(), 0, 'clearing root clears everything')
+end
+
 local function test_complete_flush()
 	local prev_count = cache.count()
 	res = cache.clear()
@@ -190,5 +196,7 @@ return {
 	test_subtree_limit,
 	test_apex,
 	import_zone,
+	test_root,
+	import_zone,
 	test_complete_flush,
 }

daemon/lua/sandbox.lua

@@ -159,7 +159,8 @@ setmetatable(modules, {
 
 
 cache.clear = function (name, exact_name, rr_type, chunk_size, callback, prev_state)
-	if name == nil then  -- keep same output format as for 'standard' clear
+	if name == nil or (name == '.' and not exact_name) then
+		-- keep same output format as for 'standard' clear
 		local total_count = cache.count()
 		if not cache.clear_everything() then
 			error('unable to clear everything')