commit 39a14ea7d7b14172595c61619e8f35c2614b2606
parent c4e7cdb541d89142056927ebdfd8f97017d38f45
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Tue, 28 Jan 2025 11:45:18 -0300
CallInfo bit CIST_CLSRET broken in two
Since commit f407b3c4a, it was being used for two distinct (and
incompatible) meanings:
A: Function has TBC variables (now bit CIST_TBC)
B: Interpreter is closing TBC variables (original bit CIST_CLSRET)
B implies A, but A does not imply B.
Diffstat:
4 files changed, 44 insertions(+), 15 deletions(-)
diff --git a/lapi.c b/lapi.c
@@ -195,7 +195,7 @@ LUA_API void lua_settop (lua_State *L, int idx) {
}
newtop = L->top.p + diff;
if (diff < 0 && L->tbclist.p >= newtop) {
- lua_assert(ci->callstatus & CIST_CLSRET);
+ lua_assert(ci->callstatus & CIST_TBC);
newtop = luaF_close(L, newtop, CLOSEKTOP, 0);
}
L->top.p = newtop; /* correct top only after closing any upvalue */
@@ -207,7 +207,7 @@ LUA_API void lua_closeslot (lua_State *L, int idx) {
StkId level;
lua_lock(L);
level = index2stack(L, idx);
- api_check(L, (L->ci->callstatus & CIST_CLSRET) && L->tbclist.p == level,
+ api_check(L, (L->ci->callstatus & CIST_TBC) && (L->tbclist.p == level),
"no variable to close at given level");
level = luaF_close(L, level, CLOSEKTOP, 0);
setnilvalue(s2v(level));
@@ -1280,7 +1280,7 @@ LUA_API void lua_toclose (lua_State *L, int idx) {
o = index2stack(L, idx);
api_check(L, L->tbclist.p < o, "given index below or equal a marked one");
luaF_newtbcupval(L, o); /* create new to-be-closed upvalue */
- L->ci->callstatus |= CIST_CLSRET; /* mark that function has TBC slots */
+ L->ci->callstatus |= CIST_TBC; /* mark that function has TBC slots */
lua_unlock(L);
}
diff --git a/ldo.c b/ldo.c
@@ -505,7 +505,7 @@ l_sinline void genmoveresults (lua_State *L, StkId res, int nres,
** Given 'nres' results at 'firstResult', move 'fwanted-1' of them
** to 'res'. Handle most typical cases (zero results for commands,
** one result for expressions, multiple results for tail calls/single
-** parameters) separated. The flag CIST_CLSRET in 'fwanted', if set,
+** parameters) separated. The flag CIST_TBC in 'fwanted', if set,
** forces the swicth to go to the default case.
*/
l_sinline void moveresults (lua_State *L, StkId res, int nres,
@@ -526,8 +526,9 @@ l_sinline void moveresults (lua_State *L, StkId res, int nres,
break;
default: { /* two/more results and/or to-be-closed variables */
int wanted = get_nresults(fwanted);
- if (fwanted & CIST_CLSRET) { /* to-be-closed variables? */
+ if (fwanted & CIST_TBC) { /* to-be-closed variables? */
L->ci->u2.nres = nres;
+ L->ci->callstatus |= CIST_CLSRET; /* in case of yields */
res = luaF_close(L, res, CLOSEKTOP, 1);
L->ci->callstatus &= ~CIST_CLSRET;
if (L->hookmask) { /* if needed, call hook after '__close's */
@@ -552,8 +553,8 @@ l_sinline void moveresults (lua_State *L, StkId res, int nres,
** that.
*/
void luaD_poscall (lua_State *L, CallInfo *ci, int nres) {
- l_uint32 fwanted = ci->callstatus & (CIST_CLSRET | CIST_NRESULTS);
- if (l_unlikely(L->hookmask) && !(fwanted & CIST_CLSRET))
+ l_uint32 fwanted = ci->callstatus & (CIST_TBC | CIST_NRESULTS);
+ if (l_unlikely(L->hookmask) && !(fwanted & CIST_TBC))
rethook(L, ci, nres);
/* move results to proper place */
moveresults(L, ci->func.p, nres, fwanted);
@@ -785,7 +786,8 @@ static int finishpcallk (lua_State *L, CallInfo *ci) {
*/
static void finishCcall (lua_State *L, CallInfo *ci) {
int n; /* actual number of results from C function */
- if (ci->callstatus & CIST_CLSRET) { /* was returning? */
+ if (ci->callstatus & CIST_CLSRET) { /* was closing TBC variable? */
+ lua_assert(ci->callstatus & CIST_TBC);
n = ci->u2.nres; /* just redo 'luaD_poscall' */
/* don't need to reset CIST_CLSRET, as it will be set again anyway */
}
diff --git a/lstate.h b/lstate.h
@@ -235,8 +235,10 @@ struct CallInfo {
#define CIST_FRESH cast(l_uint32, CIST_C << 1)
/* function is closing tbc variables */
#define CIST_CLSRET (CIST_FRESH << 1)
+/* function has tbc variables to close */
+#define CIST_TBC (CIST_CLSRET << 1)
/* original value of 'allowhook' */
-#define CIST_OAH (CIST_CLSRET << 1)
+#define CIST_OAH (CIST_TBC << 1)
/* call is running a debug hook */
#define CIST_HOOKED (CIST_OAH << 1)
/* doing a yieldable protected call */
diff --git a/testes/coroutine.lua b/testes/coroutine.lua
@@ -515,7 +515,7 @@ else
print "testing yields inside hooks"
local turn
-
+
local function fact (t, x)
assert(turn == t)
if x == 0 then return 1
@@ -642,7 +642,7 @@ else
print "testing coroutine API"
-
+
-- reusing a thread
assert(T.testC([[
newthread # create thread
@@ -920,7 +920,7 @@ do -- a few more tests for comparison operators
until res ~= 10
return res
end
-
+
local function test ()
local a1 = setmetatable({x=1}, mt1)
local a2 = setmetatable({x=2}, mt2)
@@ -932,7 +932,7 @@ do -- a few more tests for comparison operators
assert(2 >= a2)
return true
end
-
+
run(test)
end
@@ -1037,6 +1037,31 @@ f = T.makeCfunc([[
return *
]], 23, "huu")
+
+do -- testing bug introduced in commit f407b3c4a
+ local X = false -- flag "to be closed"
+ local coro = coroutine.wrap(T.testC)
+ -- runs it until 'pcallk' (that yields)
+ -- 4th argument (at index 4): object to be closed
+ local res1, res2 = coro(
+ [[
+ toclose 3 # this could break the next 'pcallk'
+ pushvalue 2 # push function 'yield' to call it
+ pushint 22; pushint 33 # arguments to yield
+ # calls 'yield' (2 args; 2 results; continuation function at index 4)
+ pcallk 2 2 4
+ invalid command (should not arrive here)
+ ]], -- 1st argument (at index 1): code;
+ coroutine.yield, -- (at index 2): function to be called
+ func2close(function () X = true end), -- (index 3): TBC slot
+ "pushint 43; return 3" -- (index 4): code for continuation function
+ )
+
+ assert(res1 == 22 and res2 == 33 and not X)
+ local res1, res2, res3 = coro(34, "hi") -- runs continuation function
+ assert(res1 == 34 and res2 == "hi" and res3 == 43 and X)
+end
+
x = coroutine.wrap(f)
assert(x() == 102)
eqtab({x()}, {23, "huu"})
@@ -1094,11 +1119,11 @@ co = coroutine.wrap(function (...) return
cannot be here!
]],
[[ # 1st continuation
- yieldk 0 3
+ yieldk 0 3
cannot be here!
]],
[[ # 2nd continuation
- yieldk 0 4
+ yieldk 0 4
cannot be here!
]],
[[ # 3th continuation
