lua/testes/memerr.lua
Roberto I 2a7cf4f319 More effort in avoiding errors in finalizers
Before calling a finalizer, Lua not only checks stack limits, but
actually ensures that a minimum number of slots are already allocated
for the call. (If it cannot ensure that, it postpones the finalizer.)
That avoids finalizers not running due to memory errors that the
programmer cannot control.
2026-01-11 15:36:03 -03:00

310 lines
7.3 KiB
Lua

-- $Id: testes/memerr.lua $
-- See Copyright Notice in file lua.h
local function checkerr (msg, f, ...)
local stat, err = pcall(f, ...)
assert(not stat and string.find(err, msg))
end
if T==nil then
(Message or print)
('\n >>> testC not active: skipping memory error tests <<<\n')
return
end
print("testing memory-allocation errors")
local debug = require "debug"
local pack = table.pack
-- standard error message for memory errors
local MEMERRMSG = "not enough memory"
-- memory error in panic function
T.totalmem(T.totalmem()+10000) -- set low memory limit (+10k)
assert(T.checkpanic("newuserdata 20000") == MEMERRMSG)
T.totalmem(0) -- restore high limit
-- {==================================================================
-- Testing memory limits
-- ===================================================================
checkerr("block too big", T.newuserdata, math.maxinteger)
collectgarbage()
local f = load"local a={}; for i=1,100000 do a[i]=i end"
T.alloccount(10)
checkerr(MEMERRMSG, f)
T.alloccount() -- remove limit
-- preallocate stack space
local function deep (n) if n > 0 then deep(n - 1) end end
-- test memory errors; increase limit for maximum memory by steps,
-- so that we get memory errors in all allocations of a given
-- task, until there is enough memory to complete the task without
-- errors.
local function testbytes (s, f)
collectgarbage()
local M = T.totalmem()
local oldM = M
local a,b = nil
while true do
collectgarbage(); collectgarbage()
deep(4)
T.totalmem(M)
a, b = T.testC("pcall 0 1 0; pushstatus; return 2", f)
T.totalmem(0) -- remove limit
if a and b == "OK" then break end -- stop when no more errors
if b ~= "OK" and b ~= MEMERRMSG then -- not a memory error?
error(a, 0) -- propagate it
end
M = M + 7 -- increase memory limit
end
print(string.format("minimum memory for %s: %d bytes", s, M - oldM))
return a
end
-- test memory errors; increase limit for number of allocations one
-- by one, so that we get memory errors in all allocations of a given
-- task, until there is enough allocations to complete the task without
-- errors.
local function testalloc (s, f)
collectgarbage()
local M = 0
local a,b = nil
while true do
collectgarbage(); collectgarbage()
deep(4)
T.alloccount(M)
a, b = T.testC("pcall 0 1 0; pushstatus; return 2", f)
T.alloccount() -- remove limit
if a and b == "OK" then break end -- stop when no more errors
if b ~= "OK" and b ~= MEMERRMSG then -- not a memory error?
error(a, 0) -- propagate it
end
M = M + 1 -- increase allocation limit
end
print(string.format("minimum allocations for %s: %d allocations", s, M))
return M
end
local function testamem (s, f)
local aloc = testalloc(s, f)
local res = testbytes(s, f)
return {aloc = aloc, res = res}
end
local b = testamem("function call", function () return 10 end)
assert(b.res == 10 and b.aloc == 0)
testamem("state creation", function ()
local st = T.newstate()
if st then T.closestate(st) end -- close new state
return st
end)
testamem("empty-table creation", function ()
return {}
end)
testamem("string creation", function ()
return "XXX" .. "YYY"
end)
testamem("coroutine creation", function()
return coroutine.create(print)
end)
do -- vararg tables
local function pack (...t) return t end
local b = testamem("vararg table", function ()
return pack(10, 20, 30, 40, "hello")
end)
assert(b.aloc == 3) -- new table uses three memory blocks
-- table optimized away
local function sel (n, ...arg) return arg[n] + arg.n end
local b = testamem("optimized vararg table",
function () return sel(2.0, 20, 30) end)
assert(b.res == 32 and b.aloc == 0) -- no memory needed for this case
end
-- testing to-be-closed variables
testamem("to-be-closed variables", function()
local flag
do
local x <close> =
setmetatable({}, {__close = function () flag = true end})
flag = false
local x = {}
end
return flag
end)
-- testing threads
-- get main thread from registry
local mt = T.testC("rawgeti R !M; return 1")
assert(type(mt) == "thread" and coroutine.running() == mt)
local function expand (n,s)
if n==0 then return "" end
local e = string.rep("=", n)
return string.format("T.doonnewstack([%s[ %s;\n collectgarbage(); %s]%s])\n",
e, s, expand(n-1,s), e)
end
G=0; collectgarbage()
load(expand(20,"G=G+1"))()
assert(G==20); collectgarbage()
G = nil
testamem("running code on new thread", function ()
return T.doonnewstack("local x=1") == 0 -- try to create thread
end)
do -- external strings
local str = string.rep("a", 100)
testamem("creating external strings", function ()
return T.externstr(str)
end)
end
-- testing memory x compiler
testamem("loadstring", function ()
return load("x=1") -- try to do load a string
end)
local testprog = [[
local function foo () return end
local t = {"x"}
AA = "aaa"
for i = 1, #t do AA = AA .. t[i] end
return true
]]
-- testing memory x dofile
_G.AA = nil
local t =os.tmpname()
local f = assert(io.open(t, "w"))
f:write(testprog)
f:close()
testamem("dofile", function ()
local a = loadfile(t)
return a and a()
end)
assert(os.remove(t))
assert(_G.AA == "aaax")
-- other generic tests
testamem("gsub", function ()
local a, b = string.gsub("alo alo", "(a)", function (x) return x..'b' end)
return (a == 'ablo ablo')
end)
testamem("dump/undump", function ()
local a = load(testprog)
local b = a and string.dump(a)
a = b and load(b)
return a and a()
end)
_G.AA = nil
local t = os.tmpname()
testamem("file creation", function ()
local f = assert(io.open(t, 'w'))
assert (not io.open"nomenaoexistente")
io.close(f);
return not loadfile'nomenaoexistente'
end)
assert(os.remove(t))
testamem("table creation", function ()
local a, lim = {}, 10
for i=1,lim do a[i] = i; a[i..'a'] = {} end
return (type(a[lim..'a']) == 'table' and a[lim] == lim)
end)
testamem("constructors", function ()
local a = {10, 20, 30, 40, 50; a=1, b=2, c=3, d=4, e=5}
return (type(a) == 'table' and a.e == 5)
end)
local a = 1
local close = nil
testamem("closure creation", function ()
function close (b)
return function (x) return b + x end
end
return (close(2)(4) == 6)
end)
testamem("using coroutines", function ()
local a = coroutine.wrap(function ()
coroutine.yield(string.rep("a", 10))
return {}
end)
assert(string.len(a()) == 10)
return a()
end)
do -- auxiliary buffer
local lim = 100
local a = {}; for i = 1, lim do a[i] = "01234567890123456789" end
testamem("auxiliary buffer", function ()
return (#table.concat(a, ",") == 20*lim + lim - 1)
end)
end
testamem("growing stack", function ()
local function foo (n)
if n == 0 then return 1 else return 1 + foo(n - 1) end
end
return foo(100)
end)
collectgarbage()
collectgarbage()
global io, T, setmetatable, collectgarbage, print
local Count = 0
testamem("finalizers", function ()
local X = false
local obj = setmetatable({}, {__gc = function () X = true end})
obj = nil
T.resetCI() -- remove extra CallInfos
T.reallocstack(18) -- remove extra stack slots
Count = Count + 1
io.stderr:write(Count, "\n")
T.trick(io)
collectgarbage()
return X
end)
-- }==================================================================
print "Ok"