From 822aedfed2ed8c4b80d466c97ff02ceca299c556 Mon Sep 17 00:00:00 2001
From: Alexander Turenko <alexander.turenko@tarantool.org>
Date: Fri, 31 May 2024 12:43:38 +0300
Subject: [PATCH] odict: fix ffi.new('void *') as a key
The problem is found by @ochaton.
NO_DOC=bugfix
NO_CHANGELOG=not a public API
---
src/box/lua/config/utils/odict.lua | 8 +++----
test/config-luatest/odict_test.lua | 36 ++++++++++++++++++++++++++++++
2 files changed, 40 insertions(+), 4 deletions(-)
diff --git a/src/box/lua/config/utils/odict.lua b/src/box/lua/config/utils/odict.lua
index ba973f7f4c..bb92e89e87 100644
--- a/src/box/lua/config/utils/odict.lua
+++ b/src/box/lua/config/utils/odict.lua
@@ -65,7 +65,7 @@ local function gen(od, prev_key)
-- The previous key is nil only on the first call of the
-- generator function.
- local id = prev_key == nil and 0 or ctx.key2id[prev_key]
+ local id = type(prev_key) == 'nil' and 0 or ctx.key2id[prev_key]
-- NB: This assert doesn't catch all the kinds of changes
-- during an iteration. It rather verifies a precondition
-- for the following cycle.
@@ -80,7 +80,7 @@ local function gen(od, prev_key)
-- id2key may contain a stalled entry, because __newindex
-- is not called on assignment of an existing field,
-- including assignment to nil.
- if key ~= nil and od[key] ~= nil then
+ if type(key) ~= 'nil' and od[key] ~= nil then
return key, od[key]
end
end
@@ -148,11 +148,11 @@ local function reindex(od, ctx)
for id = 1, old_max_id do
local key = ctx.id2key[id]
-- Drop the given key-id pair from the key<->id mappings.
- if key ~= nil then
+ if type(key) ~= 'nil' then
release(ctx, key)
end
-- Add the new key-id pair into the key<->id mappings.
- if key ~= nil and od[key] ~= nil then
+ if type(key) ~= 'nil' and od[key] ~= nil then
track(ctx, key)
end
end
diff --git a/test/config-luatest/odict_test.lua b/test/config-luatest/odict_test.lua
index 0ddd52dcd9..a66b943d3b 100644
--- a/test/config-luatest/odict_test.lua
+++ b/test/config-luatest/odict_test.lua
@@ -1,4 +1,5 @@
local fun = require('fun')
+local ffi = require('ffi')
local odict = require('internal.config.utils.odict')
local t = require('luatest')
@@ -117,6 +118,41 @@ g.test_pairs_delete_and_set = function()
})
end
+-- Using cdata as a key is unusual, but it is legal in LuaJIT.
+--
+-- There is a potential pitfall: ffi.new('void *') == nil. Let's
+-- verify that we handle such a key correctly.
+g.test_null_as_key = function()
+ local od = odict.new()
+
+ local nulls = {
+ ffi.new('void *'),
+ ffi.new('void *'),
+ ffi.new('void *'),
+ }
+
+ od[nulls[1]] = 1
+ od[nulls[2]] = 2
+ od[nulls[3]] = 3
+
+ local res = {}
+ for k, v in odict.pairs(od) do
+ table.insert(res, {k, v})
+ end
+
+ -- It doesn't differentiate nulls.
+ t.assert_equals(res, {
+ {nulls[1], 1},
+ {nulls[2], 2},
+ {nulls[3], 3},
+ })
+
+ -- It does.
+ t.assert(rawequal(res[1][1], nulls[1]))
+ t.assert(rawequal(res[2][1], nulls[2]))
+ t.assert(rawequal(res[3][1], nulls[3]))
+end
+
-- {{{ Helpers for reindexing test cases
-- Parse a range expressed like Python's slice operator.
--
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