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-rw-r--r--3rdparty/lua/src/ldo.c823
1 files changed, 509 insertions, 314 deletions
diff --git a/3rdparty/lua/src/ldo.c b/3rdparty/lua/src/ldo.c
index 90b695fb04c..a48e35f9dba 100644
--- a/3rdparty/lua/src/ldo.c
+++ b/3rdparty/lua/src/ldo.c
@@ -1,5 +1,5 @@
/*
-** $Id: ldo.c,v 2.157 2016/12/13 15:52:21 roberto Exp $
+** $Id: ldo.c $
** Stack and Call structure of Lua
** See Copyright Notice in lua.h
*/
@@ -88,7 +88,7 @@ struct lua_longjmp {
};
-static void seterrorobj (lua_State *L, int errcode, StkId oldtop) {
+void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop) {
switch (errcode) {
case LUA_ERRMEM: { /* memory error? */
setsvalue2s(L, oldtop, G(L)->memerrmsg); /* reuse preregistered msg. */
@@ -98,7 +98,12 @@ static void seterrorobj (lua_State *L, int errcode, StkId oldtop) {
setsvalue2s(L, oldtop, luaS_newliteral(L, "error in error handling"));
break;
}
+ case LUA_OK: { /* special case only for closing upvalues */
+ setnilvalue(s2v(oldtop)); /* no error message */
+ break;
+ }
default: {
+ lua_assert(errorstatus(errcode)); /* real error */
setobjs2s(L, oldtop, L->top - 1); /* error message on current top */
break;
}
@@ -114,16 +119,13 @@ l_noret luaD_throw (lua_State *L, int errcode) {
}
else { /* thread has no error handler */
global_State *g = G(L);
- L->status = cast_byte(errcode); /* mark it as dead */
+ errcode = luaE_resetthread(L, errcode); /* close all upvalues */
if (g->mainthread->errorJmp) { /* main thread has a handler? */
setobjs2s(L, g->mainthread->top++, L->top - 1); /* copy error obj. */
luaD_throw(g->mainthread, errcode); /* re-throw in main thread */
}
else { /* no handler at all; abort */
if (g->panic) { /* panic function? */
- seterrorobj(L, errcode, L->top); /* assume EXTRA_STACK */
- if (L->ci->top < L->top)
- L->ci->top = L->top; /* pushing msg. can break this invariant */
lua_unlock(L);
g->panic(L); /* call panic function (last chance to jump out) */
}
@@ -134,7 +136,7 @@ l_noret luaD_throw (lua_State *L, int errcode) {
int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud) {
- unsigned short oldnCcalls = L->nCcalls;
+ l_uint32 oldnCcalls = L->nCcalls;
struct lua_longjmp lj;
lj.status = LUA_OK;
lj.previous = L->errorJmp; /* chain new error handler */
@@ -155,17 +157,18 @@ int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud) {
** Stack reallocation
** ===================================================================
*/
-static void correctstack (lua_State *L, TValue *oldstack) {
+static void correctstack (lua_State *L, StkId oldstack, StkId newstack) {
CallInfo *ci;
UpVal *up;
- L->top = (L->top - oldstack) + L->stack;
+ L->top = (L->top - oldstack) + newstack;
+ L->tbclist = (L->tbclist - oldstack) + newstack;
for (up = L->openupval; up != NULL; up = up->u.open.next)
- up->v = (up->v - oldstack) + L->stack;
+ up->v = s2v((uplevel(up) - oldstack) + newstack);
for (ci = L->ci; ci != NULL; ci = ci->previous) {
- ci->top = (ci->top - oldstack) + L->stack;
- ci->func = (ci->func - oldstack) + L->stack;
+ ci->top = (ci->top - oldstack) + newstack;
+ ci->func = (ci->func - oldstack) + newstack;
if (isLua(ci))
- ci->u.l.base = (ci->u.l.base - oldstack) + L->stack;
+ ci->u.l.trap = 1; /* signal to update 'trap' in 'luaV_execute' */
}
}
@@ -174,66 +177,116 @@ static void correctstack (lua_State *L, TValue *oldstack) {
#define ERRORSTACKSIZE (LUAI_MAXSTACK + 200)
-void luaD_reallocstack (lua_State *L, int newsize) {
- TValue *oldstack = L->stack;
- int lim = L->stacksize;
+/*
+** Reallocate the stack to a new size, correcting all pointers into
+** it. (There are pointers to a stack from its upvalues, from its list
+** of call infos, plus a few individual pointers.) The reallocation is
+** done in two steps (allocation + free) because the correction must be
+** done while both addresses (the old stack and the new one) are valid.
+** (In ISO C, any pointer use after the pointer has been deallocated is
+** undefined behavior.)
+** In case of allocation error, raise an error or return false according
+** to 'raiseerror'.
+*/
+int luaD_reallocstack (lua_State *L, int newsize, int raiseerror) {
+ int oldsize = stacksize(L);
+ int i;
+ StkId newstack = luaM_reallocvector(L, NULL, 0,
+ newsize + EXTRA_STACK, StackValue);
lua_assert(newsize <= LUAI_MAXSTACK || newsize == ERRORSTACKSIZE);
- lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK);
- luaM_reallocvector(L, L->stack, L->stacksize, newsize, TValue);
- for (; lim < newsize; lim++)
- setnilvalue(L->stack + lim); /* erase new segment */
- L->stacksize = newsize;
- L->stack_last = L->stack + newsize - EXTRA_STACK;
- correctstack(L, oldstack);
+ if (l_unlikely(newstack == NULL)) { /* reallocation failed? */
+ if (raiseerror)
+ luaM_error(L);
+ else return 0; /* do not raise an error */
+ }
+ /* number of elements to be copied to the new stack */
+ i = ((oldsize <= newsize) ? oldsize : newsize) + EXTRA_STACK;
+ memcpy(newstack, L->stack, i * sizeof(StackValue));
+ for (; i < newsize + EXTRA_STACK; i++)
+ setnilvalue(s2v(newstack + i)); /* erase new segment */
+ correctstack(L, L->stack, newstack);
+ luaM_freearray(L, L->stack, oldsize + EXTRA_STACK);
+ L->stack = newstack;
+ L->stack_last = L->stack + newsize;
+ return 1;
}
-void luaD_growstack (lua_State *L, int n) {
- int size = L->stacksize;
- if (size > LUAI_MAXSTACK) /* error after extra size? */
- luaD_throw(L, LUA_ERRERR);
+/*
+** Try to grow the stack by at least 'n' elements. when 'raiseerror'
+** is true, raises any error; otherwise, return 0 in case of errors.
+*/
+int luaD_growstack (lua_State *L, int n, int raiseerror) {
+ int size = stacksize(L);
+ if (l_unlikely(size > LUAI_MAXSTACK)) {
+ /* if stack is larger than maximum, thread is already using the
+ extra space reserved for errors, that is, thread is handling
+ a stack error; cannot grow further than that. */
+ lua_assert(stacksize(L) == ERRORSTACKSIZE);
+ if (raiseerror)
+ luaD_throw(L, LUA_ERRERR); /* error inside message handler */
+ return 0; /* if not 'raiseerror', just signal it */
+ }
else {
- int needed = cast_int(L->top - L->stack) + n + EXTRA_STACK;
- int newsize = 2 * size;
- if (newsize > LUAI_MAXSTACK) newsize = LUAI_MAXSTACK;
- if (newsize < needed) newsize = needed;
- if (newsize > LUAI_MAXSTACK) { /* stack overflow? */
- luaD_reallocstack(L, ERRORSTACKSIZE);
- luaG_runerror(L, "stack overflow");
+ int newsize = 2 * size; /* tentative new size */
+ int needed = cast_int(L->top - L->stack) + n;
+ if (newsize > LUAI_MAXSTACK) /* cannot cross the limit */
+ newsize = LUAI_MAXSTACK;
+ if (newsize < needed) /* but must respect what was asked for */
+ newsize = needed;
+ if (l_likely(newsize <= LUAI_MAXSTACK))
+ return luaD_reallocstack(L, newsize, raiseerror);
+ else { /* stack overflow */
+ /* add extra size to be able to handle the error message */
+ luaD_reallocstack(L, ERRORSTACKSIZE, raiseerror);
+ if (raiseerror)
+ luaG_runerror(L, "stack overflow");
+ return 0;
}
- else
- luaD_reallocstack(L, newsize);
}
}
static int stackinuse (lua_State *L) {
CallInfo *ci;
+ int res;
StkId lim = L->top;
for (ci = L->ci; ci != NULL; ci = ci->previous) {
if (lim < ci->top) lim = ci->top;
}
lua_assert(lim <= L->stack_last);
- return cast_int(lim - L->stack) + 1; /* part of stack in use */
+ res = cast_int(lim - L->stack) + 1; /* part of stack in use */
+ if (res < LUA_MINSTACK)
+ res = LUA_MINSTACK; /* ensure a minimum size */
+ return res;
}
+/*
+** If stack size is more than 3 times the current use, reduce that size
+** to twice the current use. (So, the final stack size is at most 2/3 the
+** previous size, and half of its entries are empty.)
+** As a particular case, if stack was handling a stack overflow and now
+** it is not, 'max' (limited by LUAI_MAXSTACK) will be smaller than
+** stacksize (equal to ERRORSTACKSIZE in this case), and so the stack
+** will be reduced to a "regular" size.
+*/
void luaD_shrinkstack (lua_State *L) {
int inuse = stackinuse(L);
- int goodsize = inuse + (inuse / 8) + 2*EXTRA_STACK;
- if (goodsize > LUAI_MAXSTACK)
- goodsize = LUAI_MAXSTACK; /* respect stack limit */
- if (L->stacksize > LUAI_MAXSTACK) /* had been handling stack overflow? */
- luaE_freeCI(L); /* free all CIs (list grew because of an error) */
- else
- luaE_shrinkCI(L); /* shrink list */
+ int nsize = inuse * 2; /* proposed new size */
+ int max = inuse * 3; /* maximum "reasonable" size */
+ if (max > LUAI_MAXSTACK) {
+ max = LUAI_MAXSTACK; /* respect stack limit */
+ if (nsize > LUAI_MAXSTACK)
+ nsize = LUAI_MAXSTACK;
+ }
/* if thread is currently not handling a stack overflow and its
- good size is smaller than current size, shrink its stack */
- if (inuse <= (LUAI_MAXSTACK - EXTRA_STACK) &&
- goodsize < L->stacksize)
- luaD_reallocstack(L, goodsize);
+ size is larger than maximum "reasonable" size, shrink it */
+ if (inuse <= LUAI_MAXSTACK && stacksize(L) > max)
+ luaD_reallocstack(L, nsize, 0); /* ok if that fails */
else /* don't change stack */
condmovestack(L,{},{}); /* (change only for debugging) */
+ luaE_shrinkCI(L); /* shrink CI list */
}
@@ -247,24 +300,33 @@ void luaD_inctop (lua_State *L) {
/*
** Call a hook for the given event. Make sure there is a hook to be
-** called. (Both 'L->hook' and 'L->hookmask', which triggers this
+** called. (Both 'L->hook' and 'L->hookmask', which trigger this
** function, can be changed asynchronously by signals.)
*/
-void luaD_hook (lua_State *L, int event, int line) {
+void luaD_hook (lua_State *L, int event, int line,
+ int ftransfer, int ntransfer) {
lua_Hook hook = L->hook;
if (hook && L->allowhook) { /* make sure there is a hook */
+ int mask = CIST_HOOKED;
CallInfo *ci = L->ci;
- ptrdiff_t top = savestack(L, L->top);
- ptrdiff_t ci_top = savestack(L, ci->top);
+ ptrdiff_t top = savestack(L, L->top); /* preserve original 'top' */
+ ptrdiff_t ci_top = savestack(L, ci->top); /* idem for 'ci->top' */
lua_Debug ar;
ar.event = event;
ar.currentline = line;
ar.i_ci = ci;
+ if (ntransfer != 0) {
+ mask |= CIST_TRAN; /* 'ci' has transfer information */
+ ci->u2.transferinfo.ftransfer = ftransfer;
+ ci->u2.transferinfo.ntransfer = ntransfer;
+ }
+ if (isLua(ci) && L->top < ci->top)
+ L->top = ci->top; /* protect entire activation register */
luaD_checkstack(L, LUA_MINSTACK); /* ensure minimum stack size */
- ci->top = L->top + LUA_MINSTACK;
- lua_assert(ci->top <= L->stack_last);
+ if (ci->top < L->top + LUA_MINSTACK)
+ ci->top = L->top + LUA_MINSTACK;
L->allowhook = 0; /* cannot call hooks inside a hook */
- ci->callstatus |= CIST_HOOKED;
+ ci->callstatus |= mask;
lua_unlock(L);
(*hook)(L, &ar);
lua_lock(L);
@@ -272,56 +334,71 @@ void luaD_hook (lua_State *L, int event, int line) {
L->allowhook = 1;
ci->top = restorestack(L, ci_top);
L->top = restorestack(L, top);
- ci->callstatus &= ~CIST_HOOKED;
+ ci->callstatus &= ~mask;
}
}
-static void callhook (lua_State *L, CallInfo *ci) {
- int hook = LUA_HOOKCALL;
- ci->u.l.savedpc++; /* hooks assume 'pc' is already incremented */
- if (isLua(ci->previous) &&
- GET_OPCODE(*(ci->previous->u.l.savedpc - 1)) == OP_TAILCALL) {
- ci->callstatus |= CIST_TAIL;
- hook = LUA_HOOKTAILCALL;
+/*
+** Executes a call hook for Lua functions. This function is called
+** whenever 'hookmask' is not zero, so it checks whether call hooks are
+** active.
+*/
+void luaD_hookcall (lua_State *L, CallInfo *ci) {
+ L->oldpc = 0; /* set 'oldpc' for new function */
+ if (L->hookmask & LUA_MASKCALL) { /* is call hook on? */
+ int event = (ci->callstatus & CIST_TAIL) ? LUA_HOOKTAILCALL
+ : LUA_HOOKCALL;
+ Proto *p = ci_func(ci)->p;
+ ci->u.l.savedpc++; /* hooks assume 'pc' is already incremented */
+ luaD_hook(L, event, -1, 1, p->numparams);
+ ci->u.l.savedpc--; /* correct 'pc' */
}
- luaD_hook(L, hook, -1);
- ci->u.l.savedpc--; /* correct 'pc' */
}
-static StkId adjust_varargs (lua_State *L, Proto *p, int actual) {
- int i;
- int nfixargs = p->numparams;
- StkId base, fixed;
- /* move fixed parameters to final position */
- fixed = L->top - actual; /* first fixed argument */
- base = L->top; /* final position of first argument */
- for (i = 0; i < nfixargs && i < actual; i++) {
- setobjs2s(L, L->top++, fixed + i);
- setnilvalue(fixed + i); /* erase original copy (for GC) */
+/*
+** Executes a return hook for Lua and C functions and sets/corrects
+** 'oldpc'. (Note that this correction is needed by the line hook, so it
+** is done even when return hooks are off.)
+*/
+static void rethook (lua_State *L, CallInfo *ci, int nres) {
+ if (L->hookmask & LUA_MASKRET) { /* is return hook on? */
+ StkId firstres = L->top - nres; /* index of first result */
+ int delta = 0; /* correction for vararg functions */
+ int ftransfer;
+ if (isLua(ci)) {
+ Proto *p = ci_func(ci)->p;
+ if (p->is_vararg)
+ delta = ci->u.l.nextraargs + p->numparams + 1;
+ }
+ ci->func += delta; /* if vararg, back to virtual 'func' */
+ ftransfer = cast(unsigned short, firstres - ci->func);
+ luaD_hook(L, LUA_HOOKRET, -1, ftransfer, nres); /* call it */
+ ci->func -= delta;
}
- for (; i < nfixargs; i++)
- setnilvalue(L->top++); /* complete missing arguments */
- return base;
+ if (isLua(ci = ci->previous))
+ L->oldpc = pcRel(ci->u.l.savedpc, ci_func(ci)->p); /* set 'oldpc' */
}
/*
-** Check whether __call metafield of 'func' is a function. If so, put
-** it in stack below original 'func' so that 'luaD_precall' can call
-** it. Raise an error if __call metafield is not a function.
+** Check whether 'func' has a '__call' metafield. If so, put it in the
+** stack, below original 'func', so that 'luaD_precall' can call it. Raise
+** an error if there is no '__call' metafield.
*/
-static void tryfuncTM (lua_State *L, StkId func) {
- const TValue *tm = luaT_gettmbyobj(L, func, TM_CALL);
+StkId luaD_tryfuncTM (lua_State *L, StkId func) {
+ const TValue *tm;
StkId p;
- if (!ttisfunction(tm))
- luaG_typeerror(L, func, "call");
- /* Open a hole inside the stack at 'func' */
- for (p = L->top; p > func; p--)
+ checkstackGCp(L, 1, func); /* space for metamethod */
+ tm = luaT_gettmbyobj(L, s2v(func), TM_CALL); /* (after previous GC) */
+ if (l_unlikely(ttisnil(tm)))
+ luaG_callerror(L, s2v(func)); /* nothing to call */
+ for (p = L->top; p > func; p--) /* open space for metamethod */
setobjs2s(L, p, p-1);
- L->top++; /* slot ensured by caller */
- setobj2s(L, func, tm); /* tag method is the new function to be called */
+ L->top++; /* stack space pre-allocated by the caller */
+ setobj2s(L, func, tm); /* metamethod is the new function to be called */
+ return func;
}
@@ -331,229 +408,313 @@ static void tryfuncTM (lua_State *L, StkId func) {
** expressions, multiple results for tail calls/single parameters)
** separated.
*/
-static int moveresults (lua_State *L, const TValue *firstResult, StkId res,
- int nres, int wanted) {
+l_sinline void moveresults (lua_State *L, StkId res, int nres, int wanted) {
+ StkId firstresult;
+ int i;
switch (wanted) { /* handle typical cases separately */
- case 0: break; /* nothing to move */
- case 1: { /* one result needed */
+ case 0: /* no values needed */
+ L->top = res;
+ return;
+ case 1: /* one value needed */
if (nres == 0) /* no results? */
- firstResult = luaO_nilobject; /* adjust with nil */
- setobjs2s(L, res, firstResult); /* move it to proper place */
+ setnilvalue(s2v(res)); /* adjust with nil */
+ else /* at least one result */
+ setobjs2s(L, res, L->top - nres); /* move it to proper place */
+ L->top = res + 1;
+ return;
+ case LUA_MULTRET:
+ wanted = nres; /* we want all results */
break;
- }
- case LUA_MULTRET: {
- int i;
- for (i = 0; i < nres; i++) /* move all results to correct place */
- setobjs2s(L, res + i, firstResult + i);
- L->top = res + nres;
- return 0; /* wanted == LUA_MULTRET */
- }
- default: {
- int i;
- if (wanted <= nres) { /* enough results? */
- for (i = 0; i < wanted; i++) /* move wanted results to correct place */
- setobjs2s(L, res + i, firstResult + i);
- }
- else { /* not enough results; use all of them plus nils */
- for (i = 0; i < nres; i++) /* move all results to correct place */
- setobjs2s(L, res + i, firstResult + i);
- for (; i < wanted; i++) /* complete wanted number of results */
- setnilvalue(res + i);
+ default: /* two/more results and/or to-be-closed variables */
+ if (hastocloseCfunc(wanted)) { /* to-be-closed variables? */
+ ptrdiff_t savedres = savestack(L, res);
+ L->ci->callstatus |= CIST_CLSRET; /* in case of yields */
+ L->ci->u2.nres = nres;
+ luaF_close(L, res, CLOSEKTOP, 1);
+ L->ci->callstatus &= ~CIST_CLSRET;
+ if (L->hookmask) /* if needed, call hook after '__close's */
+ rethook(L, L->ci, nres);
+ res = restorestack(L, savedres); /* close and hook can move stack */
+ wanted = decodeNresults(wanted);
+ if (wanted == LUA_MULTRET)
+ wanted = nres; /* we want all results */
}
break;
- }
}
+ /* generic case */
+ firstresult = L->top - nres; /* index of first result */
+ if (nres > wanted) /* extra results? */
+ nres = wanted; /* don't need them */
+ for (i = 0; i < nres; i++) /* move all results to correct place */
+ setobjs2s(L, res + i, firstresult + i);
+ for (; i < wanted; i++) /* complete wanted number of results */
+ setnilvalue(s2v(res + i));
L->top = res + wanted; /* top points after the last result */
- return 1;
}
/*
-** Finishes a function call: calls hook if necessary, removes CallInfo,
-** moves current number of results to proper place; returns 0 iff call
-** wanted multiple (variable number of) results.
+** Finishes a function call: calls hook if necessary, moves current
+** number of results to proper place, and returns to previous call
+** info. If function has to close variables, hook must be called after
+** that.
*/
-int luaD_poscall (lua_State *L, CallInfo *ci, StkId firstResult, int nres) {
- StkId res;
+void luaD_poscall (lua_State *L, CallInfo *ci, int nres) {
int wanted = ci->nresults;
- if (L->hookmask & (LUA_MASKRET | LUA_MASKLINE)) {
- if (L->hookmask & LUA_MASKRET) {
- ptrdiff_t fr = savestack(L, firstResult); /* hook may change stack */
- luaD_hook(L, LUA_HOOKRET, -1);
- firstResult = restorestack(L, fr);
- }
- L->oldpc = ci->previous->u.l.savedpc; /* 'oldpc' for caller function */
- }
- res = ci->func; /* res == final position of 1st result */
- L->ci = ci->previous; /* back to caller */
+ if (l_unlikely(L->hookmask && !hastocloseCfunc(wanted)))
+ rethook(L, ci, nres);
/* move results to proper place */
- return moveresults(L, firstResult, res, nres, wanted);
+ moveresults(L, ci->func, nres, wanted);
+ /* function cannot be in any of these cases when returning */
+ lua_assert(!(ci->callstatus &
+ (CIST_HOOKED | CIST_YPCALL | CIST_FIN | CIST_TRAN | CIST_CLSRET)));
+ L->ci = ci->previous; /* back to caller (after closing variables) */
}
-#define next_ci(L) (L->ci = (L->ci->next ? L->ci->next : luaE_extendCI(L)))
+#define next_ci(L) (L->ci->next ? L->ci->next : luaE_extendCI(L))
-/* macro to check stack size, preserving 'p' */
-#define checkstackp(L,n,p) \
- luaD_checkstackaux(L, n, \
- ptrdiff_t t__ = savestack(L, p); /* save 'p' */ \
- luaC_checkGC(L), /* stack grow uses memory */ \
- p = restorestack(L, t__)) /* 'pos' part: restore 'p' */
+l_sinline CallInfo *prepCallInfo (lua_State *L, StkId func, int nret,
+ int mask, StkId top) {
+ CallInfo *ci = L->ci = next_ci(L); /* new frame */
+ ci->func = func;
+ ci->nresults = nret;
+ ci->callstatus = mask;
+ ci->top = top;
+ return ci;
+}
/*
-** Prepares a function call: checks the stack, creates a new CallInfo
-** entry, fills in the relevant information, calls hook if needed.
-** If function is a C function, does the call, too. (Otherwise, leave
-** the execution ('luaV_execute') to the caller, to allow stackless
-** calls.) Returns true iff function has been executed (C function).
+** precall for C functions
*/
-int luaD_precall (lua_State *L, StkId func, int nresults) {
- lua_CFunction f;
+l_sinline int precallC (lua_State *L, StkId func, int nresults,
+ lua_CFunction f) {
+ int n; /* number of returns */
CallInfo *ci;
- switch (ttype(func)) {
- case LUA_TCCL: /* C closure */
- f = clCvalue(func)->f;
- goto Cfunc;
- case LUA_TLCF: /* light C function */
- f = fvalue(func);
- Cfunc: {
- int n; /* number of returns */
- checkstackp(L, LUA_MINSTACK, func); /* ensure minimum stack size */
- ci = next_ci(L); /* now 'enter' new function */
- ci->nresults = nresults;
- ci->func = func;
- ci->top = L->top + LUA_MINSTACK;
+ checkstackGCp(L, LUA_MINSTACK, func); /* ensure minimum stack size */
+ L->ci = ci = prepCallInfo(L, func, nresults, CIST_C,
+ L->top + LUA_MINSTACK);
+ lua_assert(ci->top <= L->stack_last);
+ if (l_unlikely(L->hookmask & LUA_MASKCALL)) {
+ int narg = cast_int(L->top - func) - 1;
+ luaD_hook(L, LUA_HOOKCALL, -1, 1, narg);
+ }
+ lua_unlock(L);
+ n = (*f)(L); /* do the actual call */
+ lua_lock(L);
+ api_checknelems(L, n);
+ luaD_poscall(L, ci, n);
+ return n;
+}
+
+
+/*
+** Prepare a function for a tail call, building its call info on top
+** of the current call info. 'narg1' is the number of arguments plus 1
+** (so that it includes the function itself). Return the number of
+** results, if it was a C function, or -1 for a Lua function.
+*/
+int luaD_pretailcall (lua_State *L, CallInfo *ci, StkId func,
+ int narg1, int delta) {
+ retry:
+ switch (ttypetag(s2v(func))) {
+ case LUA_VCCL: /* C closure */
+ return precallC(L, func, LUA_MULTRET, clCvalue(s2v(func))->f);
+ case LUA_VLCF: /* light C function */
+ return precallC(L, func, LUA_MULTRET, fvalue(s2v(func)));
+ case LUA_VLCL: { /* Lua function */
+ Proto *p = clLvalue(s2v(func))->p;
+ int fsize = p->maxstacksize; /* frame size */
+ int nfixparams = p->numparams;
+ int i;
+ checkstackGCp(L, fsize - delta, func);
+ ci->func -= delta; /* restore 'func' (if vararg) */
+ for (i = 0; i < narg1; i++) /* move down function and arguments */
+ setobjs2s(L, ci->func + i, func + i);
+ func = ci->func; /* moved-down function */
+ for (; narg1 <= nfixparams; narg1++)
+ setnilvalue(s2v(func + narg1)); /* complete missing arguments */
+ ci->top = func + 1 + fsize; /* top for new function */
lua_assert(ci->top <= L->stack_last);
- ci->callstatus = 0;
- if (L->hookmask & LUA_MASKCALL)
- luaD_hook(L, LUA_HOOKCALL, -1);
- lua_unlock(L);
- n = (*f)(L); /* do the actual call */
- lua_lock(L);
- api_checknelems(L, n);
- luaD_poscall(L, ci, L->top - n, n);
- return 1;
+ ci->u.l.savedpc = p->code; /* starting point */
+ ci->callstatus |= CIST_TAIL;
+ L->top = func + narg1; /* set top */
+ return -1;
+ }
+ default: { /* not a function */
+ func = luaD_tryfuncTM(L, func); /* try to get '__call' metamethod */
+ /* return luaD_pretailcall(L, ci, func, narg1 + 1, delta); */
+ narg1++;
+ goto retry; /* try again */
}
- case LUA_TLCL: { /* Lua function: prepare its call */
- StkId base;
- Proto *p = clLvalue(func)->p;
- int n = cast_int(L->top - func) - 1; /* number of real arguments */
+ }
+}
+
+
+/*
+** Prepares the call to a function (C or Lua). For C functions, also do
+** the call. The function to be called is at '*func'. The arguments
+** are on the stack, right after the function. Returns the CallInfo
+** to be executed, if it was a Lua function. Otherwise (a C function)
+** returns NULL, with all the results on the stack, starting at the
+** original function position.
+*/
+CallInfo *luaD_precall (lua_State *L, StkId func, int nresults) {
+ retry:
+ switch (ttypetag(s2v(func))) {
+ case LUA_VCCL: /* C closure */
+ precallC(L, func, nresults, clCvalue(s2v(func))->f);
+ return NULL;
+ case LUA_VLCF: /* light C function */
+ precallC(L, func, nresults, fvalue(s2v(func)));
+ return NULL;
+ case LUA_VLCL: { /* Lua function */
+ CallInfo *ci;
+ Proto *p = clLvalue(s2v(func))->p;
+ int narg = cast_int(L->top - func) - 1; /* number of real arguments */
+ int nfixparams = p->numparams;
int fsize = p->maxstacksize; /* frame size */
- checkstackp(L, fsize, func);
- if (p->is_vararg)
- base = adjust_varargs(L, p, n);
- else { /* non vararg function */
- for (; n < p->numparams; n++)
- setnilvalue(L->top++); /* complete missing arguments */
- base = func + 1;
- }
- ci = next_ci(L); /* now 'enter' new function */
- ci->nresults = nresults;
- ci->func = func;
- ci->u.l.base = base;
- L->top = ci->top = base + fsize;
- lua_assert(ci->top <= L->stack_last);
+ checkstackGCp(L, fsize, func);
+ L->ci = ci = prepCallInfo(L, func, nresults, 0, func + 1 + fsize);
ci->u.l.savedpc = p->code; /* starting point */
- ci->callstatus = CIST_LUA;
- if (L->hookmask & LUA_MASKCALL)
- callhook(L, ci);
- return 0;
+ for (; narg < nfixparams; narg++)
+ setnilvalue(s2v(L->top++)); /* complete missing arguments */
+ lua_assert(ci->top <= L->stack_last);
+ return ci;
}
default: { /* not a function */
- checkstackp(L, 1, func); /* ensure space for metamethod */
- tryfuncTM(L, func); /* try to get '__call' metamethod */
- return luaD_precall(L, func, nresults); /* now it must be a function */
+ func = luaD_tryfuncTM(L, func); /* try to get '__call' metamethod */
+ /* return luaD_precall(L, func, nresults); */
+ goto retry; /* try again with metamethod */
}
}
}
/*
-** Check appropriate error for stack overflow ("regular" overflow or
-** overflow while handling stack overflow). If 'nCalls' is larger than
-** LUAI_MAXCCALLS (which means it is handling a "regular" overflow) but
-** smaller than 9/8 of LUAI_MAXCCALLS, does not report an error (to
-** allow overflow handling to work)
+** Call a function (C or Lua) through C. 'inc' can be 1 (increment
+** number of recursive invocations in the C stack) or nyci (the same
+** plus increment number of non-yieldable calls).
*/
-static void stackerror (lua_State *L) {
- if (L->nCcalls == LUAI_MAXCCALLS)
- luaG_runerror(L, "C stack overflow");
- else if (L->nCcalls >= (LUAI_MAXCCALLS + (LUAI_MAXCCALLS>>3)))
- luaD_throw(L, LUA_ERRERR); /* error while handing stack error */
+l_sinline void ccall (lua_State *L, StkId func, int nResults, int inc) {
+ CallInfo *ci;
+ L->nCcalls += inc;
+ if (l_unlikely(getCcalls(L) >= LUAI_MAXCCALLS))
+ luaE_checkcstack(L);
+ if ((ci = luaD_precall(L, func, nResults)) != NULL) { /* Lua function? */
+ ci->callstatus = CIST_FRESH; /* mark that it is a "fresh" execute */
+ luaV_execute(L, ci); /* call it */
+ }
+ L->nCcalls -= inc;
}
/*
-** Call a function (C or Lua). The function to be called is at *func.
-** The arguments are on the stack, right after the function.
-** When returns, all the results are on the stack, starting at the original
-** function position.
+** External interface for 'ccall'
*/
void luaD_call (lua_State *L, StkId func, int nResults) {
- if (++L->nCcalls >= LUAI_MAXCCALLS)
- stackerror(L);
- if (!luaD_precall(L, func, nResults)) /* is a Lua function? */
- luaV_execute(L); /* call it */
- L->nCcalls--;
+ ccall(L, func, nResults, 1);
}
/*
-** Similar to 'luaD_call', but does not allow yields during the call
+** Similar to 'luaD_call', but does not allow yields during the call.
*/
void luaD_callnoyield (lua_State *L, StkId func, int nResults) {
- L->nny++;
- luaD_call(L, func, nResults);
- L->nny--;
+ ccall(L, func, nResults, nyci);
}
/*
-** Completes the execution of an interrupted C function, calling its
-** continuation function.
+** Finish the job of 'lua_pcallk' after it was interrupted by an yield.
+** (The caller, 'finishCcall', does the final call to 'adjustresults'.)
+** The main job is to complete the 'luaD_pcall' called by 'lua_pcallk'.
+** If a '__close' method yields here, eventually control will be back
+** to 'finishCcall' (when that '__close' method finally returns) and
+** 'finishpcallk' will run again and close any still pending '__close'
+** methods. Similarly, if a '__close' method errs, 'precover' calls
+** 'unroll' which calls ''finishCcall' and we are back here again, to
+** close any pending '__close' methods.
+** Note that, up to the call to 'luaF_close', the corresponding
+** 'CallInfo' is not modified, so that this repeated run works like the
+** first one (except that it has at least one less '__close' to do). In
+** particular, field CIST_RECST preserves the error status across these
+** multiple runs, changing only if there is a new error.
*/
-static void finishCcall (lua_State *L, int status) {
- CallInfo *ci = L->ci;
- int n;
- /* must have a continuation and must be able to call it */
- lua_assert(ci->u.c.k != NULL && L->nny == 0);
- /* error status can only happen in a protected call */
- lua_assert((ci->callstatus & CIST_YPCALL) || status == LUA_YIELD);
- if (ci->callstatus & CIST_YPCALL) { /* was inside a pcall? */
- ci->callstatus &= ~CIST_YPCALL; /* continuation is also inside it */
- L->errfunc = ci->u.c.old_errfunc; /* with the same error function */
- }
- /* finish 'lua_callk'/'lua_pcall'; CIST_YPCALL and 'errfunc' already
- handled */
- adjustresults(L, ci->nresults);
- lua_unlock(L);
- n = (*ci->u.c.k)(L, status, ci->u.c.ctx); /* call continuation function */
- lua_lock(L);
- api_checknelems(L, n);
- luaD_poscall(L, ci, L->top - n, n); /* finish 'luaD_precall' */
+static int finishpcallk (lua_State *L, CallInfo *ci) {
+ int status = getcistrecst(ci); /* get original status */
+ if (l_likely(status == LUA_OK)) /* no error? */
+ status = LUA_YIELD; /* was interrupted by an yield */
+ else { /* error */
+ StkId func = restorestack(L, ci->u2.funcidx);
+ L->allowhook = getoah(ci->callstatus); /* restore 'allowhook' */
+ luaF_close(L, func, status, 1); /* can yield or raise an error */
+ func = restorestack(L, ci->u2.funcidx); /* stack may be moved */
+ luaD_seterrorobj(L, status, func);
+ luaD_shrinkstack(L); /* restore stack size in case of overflow */
+ setcistrecst(ci, LUA_OK); /* clear original status */
+ }
+ ci->callstatus &= ~CIST_YPCALL;
+ L->errfunc = ci->u.c.old_errfunc;
+ /* if it is here, there were errors or yields; unlike 'lua_pcallk',
+ do not change status */
+ return status;
+}
+
+
+/*
+** Completes the execution of a C function interrupted by an yield.
+** The interruption must have happened while the function was either
+** closing its tbc variables in 'moveresults' or executing
+** 'lua_callk'/'lua_pcallk'. In the first case, it just redoes
+** 'luaD_poscall'. In the second case, the call to 'finishpcallk'
+** finishes the interrupted execution of 'lua_pcallk'. After that, it
+** calls the continuation of the interrupted function and finally it
+** completes the job of the 'luaD_call' that called the function. In
+** the call to 'adjustresults', we do not know the number of results
+** of the function called by 'lua_callk'/'lua_pcallk', so we are
+** conservative and use LUA_MULTRET (always adjust).
+*/
+static void finishCcall (lua_State *L, CallInfo *ci) {
+ int n; /* actual number of results from C function */
+ if (ci->callstatus & CIST_CLSRET) { /* was returning? */
+ lua_assert(hastocloseCfunc(ci->nresults));
+ n = ci->u2.nres; /* just redo 'luaD_poscall' */
+ /* don't need to reset CIST_CLSRET, as it will be set again anyway */
+ }
+ else {
+ int status = LUA_YIELD; /* default if there were no errors */
+ /* must have a continuation and must be able to call it */
+ lua_assert(ci->u.c.k != NULL && yieldable(L));
+ if (ci->callstatus & CIST_YPCALL) /* was inside a 'lua_pcallk'? */
+ status = finishpcallk(L, ci); /* finish it */
+ adjustresults(L, LUA_MULTRET); /* finish 'lua_callk' */
+ lua_unlock(L);
+ n = (*ci->u.c.k)(L, status, ci->u.c.ctx); /* call continuation */
+ lua_lock(L);
+ api_checknelems(L, n);
+ }
+ luaD_poscall(L, ci, n); /* finish 'luaD_call' */
}
/*
** Executes "full continuation" (everything in the stack) of a
** previously interrupted coroutine until the stack is empty (or another
-** interruption long-jumps out of the loop). If the coroutine is
-** recovering from an error, 'ud' points to the error status, which must
-** be passed to the first continuation function (otherwise the default
-** status is LUA_YIELD).
+** interruption long-jumps out of the loop).
*/
static void unroll (lua_State *L, void *ud) {
- if (ud != NULL) /* error status? */
- finishCcall(L, *(int *)ud); /* finish 'lua_pcallk' callee */
- while (L->ci != &L->base_ci) { /* something in the stack */
- if (!isLua(L->ci)) /* C function? */
- finishCcall(L, LUA_YIELD); /* complete its execution */
+ CallInfo *ci;
+ UNUSED(ud);
+ while ((ci = L->ci) != &L->base_ci) { /* something in the stack */
+ if (!isLua(ci)) /* C function? */
+ finishCcall(L, ci); /* complete its execution */
else { /* Lua function */
luaV_finishOp(L); /* finish interrupted instruction */
- luaV_execute(L); /* execute down to higher C 'boundary' */
+ luaV_execute(L, ci); /* execute down to higher C 'boundary' */
}
}
}
@@ -574,28 +735,6 @@ static CallInfo *findpcall (lua_State *L) {
/*
-** Recovers from an error in a coroutine. Finds a recover point (if
-** there is one) and completes the execution of the interrupted
-** 'luaD_pcall'. If there is no recover point, returns zero.
-*/
-static int recover (lua_State *L, int status) {
- StkId oldtop;
- CallInfo *ci = findpcall(L);
- if (ci == NULL) return 0; /* no recovery point */
- /* "finish" luaD_pcall */
- oldtop = restorestack(L, ci->extra);
- luaF_close(L, oldtop);
- seterrorobj(L, status, oldtop);
- L->ci = ci;
- L->allowhook = getoah(ci->callstatus); /* restore original 'allowhook' */
- L->nny = 0; /* should be zero to be yieldable */
- luaD_shrinkstack(L);
- L->errfunc = ci->u.c.old_errfunc;
- return 1; /* continue running the coroutine */
-}
-
-
-/*
** Signal an error in the call to 'lua_resume', not in the execution
** of the coroutine itself. (Such errors should not be handled by any
** coroutine error handler and should not kill the coroutine.)
@@ -620,96 +759,111 @@ static void resume (lua_State *L, void *ud) {
int n = *(cast(int*, ud)); /* number of arguments */
StkId firstArg = L->top - n; /* first argument */
CallInfo *ci = L->ci;
- if (L->status == LUA_OK) { /* starting a coroutine? */
- if (!luaD_precall(L, firstArg - 1, LUA_MULTRET)) /* Lua function? */
- luaV_execute(L); /* call it */
- }
+ if (L->status == LUA_OK) /* starting a coroutine? */
+ ccall(L, firstArg - 1, LUA_MULTRET, 0); /* just call its body */
else { /* resuming from previous yield */
lua_assert(L->status == LUA_YIELD);
L->status = LUA_OK; /* mark that it is running (again) */
- ci->func = restorestack(L, ci->extra);
- if (isLua(ci)) /* yielded inside a hook? */
- luaV_execute(L); /* just continue running Lua code */
+ if (isLua(ci)) { /* yielded inside a hook? */
+ L->top = firstArg; /* discard arguments */
+ luaV_execute(L, ci); /* just continue running Lua code */
+ }
else { /* 'common' yield */
if (ci->u.c.k != NULL) { /* does it have a continuation function? */
lua_unlock(L);
n = (*ci->u.c.k)(L, LUA_YIELD, ci->u.c.ctx); /* call continuation */
lua_lock(L);
api_checknelems(L, n);
- firstArg = L->top - n; /* yield results come from continuation */
}
- luaD_poscall(L, ci, firstArg, n); /* finish 'luaD_precall' */
+ luaD_poscall(L, ci, n); /* finish 'luaD_call' */
}
unroll(L, NULL); /* run continuation */
}
}
-LUA_API int lua_resume (lua_State *L, lua_State *from, int nargs) {
+/*
+** Unrolls a coroutine in protected mode while there are recoverable
+** errors, that is, errors inside a protected call. (Any error
+** interrupts 'unroll', and this loop protects it again so it can
+** continue.) Stops with a normal end (status == LUA_OK), an yield
+** (status == LUA_YIELD), or an unprotected error ('findpcall' doesn't
+** find a recover point).
+*/
+static int precover (lua_State *L, int status) {
+ CallInfo *ci;
+ while (errorstatus(status) && (ci = findpcall(L)) != NULL) {
+ L->ci = ci; /* go down to recovery functions */
+ setcistrecst(ci, status); /* status to finish 'pcall' */
+ status = luaD_rawrunprotected(L, unroll, NULL);
+ }
+ return status;
+}
+
+
+LUA_API int lua_resume (lua_State *L, lua_State *from, int nargs,
+ int *nresults) {
int status;
- unsigned short oldnny = L->nny; /* save "number of non-yieldable" calls */
lua_lock(L);
if (L->status == LUA_OK) { /* may be starting a coroutine */
if (L->ci != &L->base_ci) /* not in base level? */
return resume_error(L, "cannot resume non-suspended coroutine", nargs);
+ else if (L->top - (L->ci->func + 1) == nargs) /* no function? */
+ return resume_error(L, "cannot resume dead coroutine", nargs);
}
- else if (L->status != LUA_YIELD)
+ else if (L->status != LUA_YIELD) /* ended with errors? */
return resume_error(L, "cannot resume dead coroutine", nargs);
- L->nCcalls = (from) ? from->nCcalls + 1 : 1;
- if (L->nCcalls >= LUAI_MAXCCALLS)
+ L->nCcalls = (from) ? getCcalls(from) : 0;
+ if (getCcalls(L) >= LUAI_MAXCCALLS)
return resume_error(L, "C stack overflow", nargs);
+ L->nCcalls++;
luai_userstateresume(L, nargs);
- L->nny = 0; /* allow yields */
api_checknelems(L, (L->status == LUA_OK) ? nargs + 1 : nargs);
status = luaD_rawrunprotected(L, resume, &nargs);
- if (status == -1) /* error calling 'lua_resume'? */
- status = LUA_ERRRUN;
- else { /* continue running after recoverable errors */
- while (errorstatus(status) && recover(L, status)) {
- /* unroll continuation */
- status = luaD_rawrunprotected(L, unroll, &status);
- }
- if (errorstatus(status)) { /* unrecoverable error? */
- L->status = cast_byte(status); /* mark thread as 'dead' */
- seterrorobj(L, status, L->top); /* push error message */
- L->ci->top = L->top;
- }
- else lua_assert(status == L->status); /* normal end or yield */
+ /* continue running after recoverable errors */
+ status = precover(L, status);
+ if (l_likely(!errorstatus(status)))
+ lua_assert(status == L->status); /* normal end or yield */
+ else { /* unrecoverable error */
+ L->status = cast_byte(status); /* mark thread as 'dead' */
+ luaD_seterrorobj(L, status, L->top); /* push error message */
+ L->ci->top = L->top;
}
- L->nny = oldnny; /* restore 'nny' */
- L->nCcalls--;
- lua_assert(L->nCcalls == ((from) ? from->nCcalls : 0));
+ *nresults = (status == LUA_YIELD) ? L->ci->u2.nyield
+ : cast_int(L->top - (L->ci->func + 1));
lua_unlock(L);
return status;
}
LUA_API int lua_isyieldable (lua_State *L) {
- return (L->nny == 0);
+ return yieldable(L);
}
LUA_API int lua_yieldk (lua_State *L, int nresults, lua_KContext ctx,
lua_KFunction k) {
- CallInfo *ci = L->ci;
+ CallInfo *ci;
luai_userstateyield(L, nresults);
lua_lock(L);
+ ci = L->ci;
api_checknelems(L, nresults);
- if (L->nny > 0) {
+ if (l_unlikely(!yieldable(L))) {
if (L != G(L)->mainthread)
luaG_runerror(L, "attempt to yield across a C-call boundary");
else
luaG_runerror(L, "attempt to yield from outside a coroutine");
}
L->status = LUA_YIELD;
- ci->extra = savestack(L, ci->func); /* save current 'func' */
+ ci->u2.nyield = nresults; /* save number of results */
if (isLua(ci)) { /* inside a hook? */
+ lua_assert(!isLuacode(ci));
+ api_check(L, nresults == 0, "hooks cannot yield values");
api_check(L, k == NULL, "hooks cannot continue after yielding");
}
else {
if ((ci->u.c.k = k) != NULL) /* is there a continuation? */
ci->u.c.ctx = ctx; /* save context */
- ci->func = L->top - nresults - 1; /* protect stack below results */
luaD_throw(L, LUA_YIELD);
}
lua_assert(ci->callstatus & CIST_HOOKED); /* must be inside a hook */
@@ -718,23 +872,64 @@ LUA_API int lua_yieldk (lua_State *L, int nresults, lua_KContext ctx,
}
+/*
+** Auxiliary structure to call 'luaF_close' in protected mode.
+*/
+struct CloseP {
+ StkId level;
+ int status;
+};
+
+
+/*
+** Auxiliary function to call 'luaF_close' in protected mode.
+*/
+static void closepaux (lua_State *L, void *ud) {
+ struct CloseP *pcl = cast(struct CloseP *, ud);
+ luaF_close(L, pcl->level, pcl->status, 0);
+}
+
+
+/*
+** Calls 'luaF_close' in protected mode. Return the original status
+** or, in case of errors, the new status.
+*/
+int luaD_closeprotected (lua_State *L, ptrdiff_t level, int status) {
+ CallInfo *old_ci = L->ci;
+ lu_byte old_allowhooks = L->allowhook;
+ for (;;) { /* keep closing upvalues until no more errors */
+ struct CloseP pcl;
+ pcl.level = restorestack(L, level); pcl.status = status;
+ status = luaD_rawrunprotected(L, &closepaux, &pcl);
+ if (l_likely(status == LUA_OK)) /* no more errors? */
+ return pcl.status;
+ else { /* an error occurred; restore saved state and repeat */
+ L->ci = old_ci;
+ L->allowhook = old_allowhooks;
+ }
+ }
+}
+
+
+/*
+** Call the C function 'func' in protected mode, restoring basic
+** thread information ('allowhook', etc.) and in particular
+** its stack level in case of errors.
+*/
int luaD_pcall (lua_State *L, Pfunc func, void *u,
ptrdiff_t old_top, ptrdiff_t ef) {
int status;
CallInfo *old_ci = L->ci;
lu_byte old_allowhooks = L->allowhook;
- unsigned short old_nny = L->nny;
ptrdiff_t old_errfunc = L->errfunc;
L->errfunc = ef;
status = luaD_rawrunprotected(L, func, u);
- if (status != LUA_OK) { /* an error occurred? */
- StkId oldtop = restorestack(L, old_top);
- luaF_close(L, oldtop); /* close possible pending closures */
- seterrorobj(L, status, oldtop);
+ if (l_unlikely(status != LUA_OK)) { /* an error occurred? */
L->ci = old_ci;
L->allowhook = old_allowhooks;
- L->nny = old_nny;
- luaD_shrinkstack(L);
+ status = luaD_closeprotected(L, old_top, status);
+ luaD_seterrorobj(L, status, restorestack(L, old_top));
+ luaD_shrinkstack(L); /* restore stack size in case of overflow */
}
L->errfunc = old_errfunc;
return status;
@@ -784,7 +979,7 @@ int luaD_protectedparser (lua_State *L, ZIO *z, const char *name,
const char *mode) {
struct SParser p;
int status;
- L->nny++; /* cannot yield during parsing */
+ incnny(L); /* cannot yield during parsing */
p.z = z; p.name = name; p.mode = mode;
p.dyd.actvar.arr = NULL; p.dyd.actvar.size = 0;
p.dyd.gt.arr = NULL; p.dyd.gt.size = 0;
@@ -795,7 +990,7 @@ int luaD_protectedparser (lua_State *L, ZIO *z, const char *name,
luaM_freearray(L, p.dyd.actvar.arr, p.dyd.actvar.size);
luaM_freearray(L, p.dyd.gt.arr, p.dyd.gt.size);
luaM_freearray(L, p.dyd.label.arr, p.dyd.label.size);
- L->nny--;
+ decnny(L);
return status;
}