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Diffstat (limited to 'lua-5.3.5/ldebug.c')
-rw-r--r--lua-5.3.5/ldebug.c699
1 files changed, 699 insertions, 0 deletions
diff --git a/lua-5.3.5/ldebug.c b/lua-5.3.5/ldebug.c
new file mode 100644
index 0000000..e138929
--- /dev/null
+++ b/lua-5.3.5/ldebug.c
@@ -0,0 +1,699 @@
+/*
+** $Id: ldebug.c,v 2.121.1.2 2017/07/10 17:21:50 roberto Exp $
+** Debug Interface
+** See Copyright Notice in lua.h
+*/
+
+#define ldebug_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <stdarg.h>
+#include <stddef.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lapi.h"
+#include "lcode.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+#include "lvm.h"
+
+
+
+#define noLuaClosure(f) ((f) == NULL || (f)->c.tt == LUA_TCCL)
+
+
+/* Active Lua function (given call info) */
+#define ci_func(ci) (clLvalue((ci)->func))
+
+
+static const char *funcnamefromcode (lua_State *L, CallInfo *ci,
+ const char **name);
+
+
+static int currentpc (CallInfo *ci) {
+ lua_assert(isLua(ci));
+ return pcRel(ci->u.l.savedpc, ci_func(ci)->p);
+}
+
+
+static int currentline (CallInfo *ci) {
+ return getfuncline(ci_func(ci)->p, currentpc(ci));
+}
+
+
+/*
+** If function yielded, its 'func' can be in the 'extra' field. The
+** next function restores 'func' to its correct value for debugging
+** purposes. (It exchanges 'func' and 'extra'; so, when called again,
+** after debugging, it also "re-restores" ** 'func' to its altered value.
+*/
+static void swapextra (lua_State *L) {
+ if (L->status == LUA_YIELD) {
+ CallInfo *ci = L->ci; /* get function that yielded */
+ StkId temp = ci->func; /* exchange its 'func' and 'extra' values */
+ ci->func = restorestack(L, ci->extra);
+ ci->extra = savestack(L, temp);
+ }
+}
+
+
+/*
+** This function can be called asynchronously (e.g. during a signal).
+** Fields 'oldpc', 'basehookcount', and 'hookcount' (set by
+** 'resethookcount') are for debug only, and it is no problem if they
+** get arbitrary values (causes at most one wrong hook call). 'hookmask'
+** is an atomic value. We assume that pointers are atomic too (e.g., gcc
+** ensures that for all platforms where it runs). Moreover, 'hook' is
+** always checked before being called (see 'luaD_hook').
+*/
+LUA_API void lua_sethook (lua_State *L, lua_Hook func, int mask, int count) {
+ if (func == NULL || mask == 0) { /* turn off hooks? */
+ mask = 0;
+ func = NULL;
+ }
+ if (isLua(L->ci))
+ L->oldpc = L->ci->u.l.savedpc;
+ L->hook = func;
+ L->basehookcount = count;
+ resethookcount(L);
+ L->hookmask = cast_byte(mask);
+}
+
+
+LUA_API lua_Hook lua_gethook (lua_State *L) {
+ return L->hook;
+}
+
+
+LUA_API int lua_gethookmask (lua_State *L) {
+ return L->hookmask;
+}
+
+
+LUA_API int lua_gethookcount (lua_State *L) {
+ return L->basehookcount;
+}
+
+
+LUA_API int lua_getstack (lua_State *L, int level, lua_Debug *ar) {
+ int status;
+ CallInfo *ci;
+ if (level < 0) return 0; /* invalid (negative) level */
+ lua_lock(L);
+ for (ci = L->ci; level > 0 && ci != &L->base_ci; ci = ci->previous)
+ level--;
+ if (level == 0 && ci != &L->base_ci) { /* level found? */
+ status = 1;
+ ar->i_ci = ci;
+ }
+ else status = 0; /* no such level */
+ lua_unlock(L);
+ return status;
+}
+
+
+static const char *upvalname (Proto *p, int uv) {
+ TString *s = check_exp(uv < p->sizeupvalues, p->upvalues[uv].name);
+ if (s == NULL) return "?";
+ else return getstr(s);
+}
+
+
+static const char *findvararg (CallInfo *ci, int n, StkId *pos) {
+ int nparams = clLvalue(ci->func)->p->numparams;
+ if (n >= cast_int(ci->u.l.base - ci->func) - nparams)
+ return NULL; /* no such vararg */
+ else {
+ *pos = ci->func + nparams + n;
+ return "(*vararg)"; /* generic name for any vararg */
+ }
+}
+
+
+static const char *findlocal (lua_State *L, CallInfo *ci, int n,
+ StkId *pos) {
+ const char *name = NULL;
+ StkId base;
+ if (isLua(ci)) {
+ if (n < 0) /* access to vararg values? */
+ return findvararg(ci, -n, pos);
+ else {
+ base = ci->u.l.base;
+ name = luaF_getlocalname(ci_func(ci)->p, n, currentpc(ci));
+ }
+ }
+ else
+ base = ci->func + 1;
+ if (name == NULL) { /* no 'standard' name? */
+ StkId limit = (ci == L->ci) ? L->top : ci->next->func;
+ if (limit - base >= n && n > 0) /* is 'n' inside 'ci' stack? */
+ name = "(*temporary)"; /* generic name for any valid slot */
+ else
+ return NULL; /* no name */
+ }
+ *pos = base + (n - 1);
+ return name;
+}
+
+
+LUA_API const char *lua_getlocal (lua_State *L, const lua_Debug *ar, int n) {
+ const char *name;
+ lua_lock(L);
+ swapextra(L);
+ if (ar == NULL) { /* information about non-active function? */
+ if (!isLfunction(L->top - 1)) /* not a Lua function? */
+ name = NULL;
+ else /* consider live variables at function start (parameters) */
+ name = luaF_getlocalname(clLvalue(L->top - 1)->p, n, 0);
+ }
+ else { /* active function; get information through 'ar' */
+ StkId pos = NULL; /* to avoid warnings */
+ name = findlocal(L, ar->i_ci, n, &pos);
+ if (name) {
+ setobj2s(L, L->top, pos);
+ api_incr_top(L);
+ }
+ }
+ swapextra(L);
+ lua_unlock(L);
+ return name;
+}
+
+
+LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n) {
+ StkId pos = NULL; /* to avoid warnings */
+ const char *name;
+ lua_lock(L);
+ swapextra(L);
+ name = findlocal(L, ar->i_ci, n, &pos);
+ if (name) {
+ setobjs2s(L, pos, L->top - 1);
+ L->top--; /* pop value */
+ }
+ swapextra(L);
+ lua_unlock(L);
+ return name;
+}
+
+
+static void funcinfo (lua_Debug *ar, Closure *cl) {
+ if (noLuaClosure(cl)) {
+ ar->source = "=[C]";
+ ar->linedefined = -1;
+ ar->lastlinedefined = -1;
+ ar->what = "C";
+ }
+ else {
+ Proto *p = cl->l.p;
+ ar->source = p->source ? getstr(p->source) : "=?";
+ ar->linedefined = p->linedefined;
+ ar->lastlinedefined = p->lastlinedefined;
+ ar->what = (ar->linedefined == 0) ? "main" : "Lua";
+ }
+ luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE);
+}
+
+
+static void collectvalidlines (lua_State *L, Closure *f) {
+ if (noLuaClosure(f)) {
+ setnilvalue(L->top);
+ api_incr_top(L);
+ }
+ else {
+ int i;
+ TValue v;
+ int *lineinfo = f->l.p->lineinfo;
+ Table *t = luaH_new(L); /* new table to store active lines */
+ sethvalue(L, L->top, t); /* push it on stack */
+ api_incr_top(L);
+ setbvalue(&v, 1); /* boolean 'true' to be the value of all indices */
+ for (i = 0; i < f->l.p->sizelineinfo; i++) /* for all lines with code */
+ luaH_setint(L, t, lineinfo[i], &v); /* table[line] = true */
+ }
+}
+
+
+static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name) {
+ if (ci == NULL) /* no 'ci'? */
+ return NULL; /* no info */
+ else if (ci->callstatus & CIST_FIN) { /* is this a finalizer? */
+ *name = "__gc";
+ return "metamethod"; /* report it as such */
+ }
+ /* calling function is a known Lua function? */
+ else if (!(ci->callstatus & CIST_TAIL) && isLua(ci->previous))
+ return funcnamefromcode(L, ci->previous, name);
+ else return NULL; /* no way to find a name */
+}
+
+
+static int auxgetinfo (lua_State *L, const char *what, lua_Debug *ar,
+ Closure *f, CallInfo *ci) {
+ int status = 1;
+ for (; *what; what++) {
+ switch (*what) {
+ case 'S': {
+ funcinfo(ar, f);
+ break;
+ }
+ case 'l': {
+ ar->currentline = (ci && isLua(ci)) ? currentline(ci) : -1;
+ break;
+ }
+ case 'u': {
+ ar->nups = (f == NULL) ? 0 : f->c.nupvalues;
+ if (noLuaClosure(f)) {
+ ar->isvararg = 1;
+ ar->nparams = 0;
+ }
+ else {
+ ar->isvararg = f->l.p->is_vararg;
+ ar->nparams = f->l.p->numparams;
+ }
+ break;
+ }
+ case 't': {
+ ar->istailcall = (ci) ? ci->callstatus & CIST_TAIL : 0;
+ break;
+ }
+ case 'n': {
+ ar->namewhat = getfuncname(L, ci, &ar->name);
+ if (ar->namewhat == NULL) {
+ ar->namewhat = ""; /* not found */
+ ar->name = NULL;
+ }
+ break;
+ }
+ case 'L':
+ case 'f': /* handled by lua_getinfo */
+ break;
+ default: status = 0; /* invalid option */
+ }
+ }
+ return status;
+}
+
+
+LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) {
+ int status;
+ Closure *cl;
+ CallInfo *ci;
+ StkId func;
+ lua_lock(L);
+ swapextra(L);
+ if (*what == '>') {
+ ci = NULL;
+ func = L->top - 1;
+ api_check(L, ttisfunction(func), "function expected");
+ what++; /* skip the '>' */
+ L->top--; /* pop function */
+ }
+ else {
+ ci = ar->i_ci;
+ func = ci->func;
+ lua_assert(ttisfunction(ci->func));
+ }
+ cl = ttisclosure(func) ? clvalue(func) : NULL;
+ status = auxgetinfo(L, what, ar, cl, ci);
+ if (strchr(what, 'f')) {
+ setobjs2s(L, L->top, func);
+ api_incr_top(L);
+ }
+ swapextra(L); /* correct before option 'L', which can raise a mem. error */
+ if (strchr(what, 'L'))
+ collectvalidlines(L, cl);
+ lua_unlock(L);
+ return status;
+}
+
+
+/*
+** {======================================================
+** Symbolic Execution
+** =======================================================
+*/
+
+static const char *getobjname (Proto *p, int lastpc, int reg,
+ const char **name);
+
+
+/*
+** find a "name" for the RK value 'c'
+*/
+static void kname (Proto *p, int pc, int c, const char **name) {
+ if (ISK(c)) { /* is 'c' a constant? */
+ TValue *kvalue = &p->k[INDEXK(c)];
+ if (ttisstring(kvalue)) { /* literal constant? */
+ *name = svalue(kvalue); /* it is its own name */
+ return;
+ }
+ /* else no reasonable name found */
+ }
+ else { /* 'c' is a register */
+ const char *what = getobjname(p, pc, c, name); /* search for 'c' */
+ if (what && *what == 'c') { /* found a constant name? */
+ return; /* 'name' already filled */
+ }
+ /* else no reasonable name found */
+ }
+ *name = "?"; /* no reasonable name found */
+}
+
+
+static int filterpc (int pc, int jmptarget) {
+ if (pc < jmptarget) /* is code conditional (inside a jump)? */
+ return -1; /* cannot know who sets that register */
+ else return pc; /* current position sets that register */
+}
+
+
+/*
+** try to find last instruction before 'lastpc' that modified register 'reg'
+*/
+static int findsetreg (Proto *p, int lastpc, int reg) {
+ int pc;
+ int setreg = -1; /* keep last instruction that changed 'reg' */
+ int jmptarget = 0; /* any code before this address is conditional */
+ for (pc = 0; pc < lastpc; pc++) {
+ Instruction i = p->code[pc];
+ OpCode op = GET_OPCODE(i);
+ int a = GETARG_A(i);
+ switch (op) {
+ case OP_LOADNIL: {
+ int b = GETARG_B(i);
+ if (a <= reg && reg <= a + b) /* set registers from 'a' to 'a+b' */
+ setreg = filterpc(pc, jmptarget);
+ break;
+ }
+ case OP_TFORCALL: {
+ if (reg >= a + 2) /* affect all regs above its base */
+ setreg = filterpc(pc, jmptarget);
+ break;
+ }
+ case OP_CALL:
+ case OP_TAILCALL: {
+ if (reg >= a) /* affect all registers above base */
+ setreg = filterpc(pc, jmptarget);
+ break;
+ }
+ case OP_JMP: {
+ int b = GETARG_sBx(i);
+ int dest = pc + 1 + b;
+ /* jump is forward and do not skip 'lastpc'? */
+ if (pc < dest && dest <= lastpc) {
+ if (dest > jmptarget)
+ jmptarget = dest; /* update 'jmptarget' */
+ }
+ break;
+ }
+ default:
+ if (testAMode(op) && reg == a) /* any instruction that set A */
+ setreg = filterpc(pc, jmptarget);
+ break;
+ }
+ }
+ return setreg;
+}
+
+
+static const char *getobjname (Proto *p, int lastpc, int reg,
+ const char **name) {
+ int pc;
+ *name = luaF_getlocalname(p, reg + 1, lastpc);
+ if (*name) /* is a local? */
+ return "local";
+ /* else try symbolic execution */
+ pc = findsetreg(p, lastpc, reg);
+ if (pc != -1) { /* could find instruction? */
+ Instruction i = p->code[pc];
+ OpCode op = GET_OPCODE(i);
+ switch (op) {
+ case OP_MOVE: {
+ int b = GETARG_B(i); /* move from 'b' to 'a' */
+ if (b < GETARG_A(i))
+ return getobjname(p, pc, b, name); /* get name for 'b' */
+ break;
+ }
+ case OP_GETTABUP:
+ case OP_GETTABLE: {
+ int k = GETARG_C(i); /* key index */
+ int t = GETARG_B(i); /* table index */
+ const char *vn = (op == OP_GETTABLE) /* name of indexed variable */
+ ? luaF_getlocalname(p, t + 1, pc)
+ : upvalname(p, t);
+ kname(p, pc, k, name);
+ return (vn && strcmp(vn, LUA_ENV) == 0) ? "global" : "field";
+ }
+ case OP_GETUPVAL: {
+ *name = upvalname(p, GETARG_B(i));
+ return "upvalue";
+ }
+ case OP_LOADK:
+ case OP_LOADKX: {
+ int b = (op == OP_LOADK) ? GETARG_Bx(i)
+ : GETARG_Ax(p->code[pc + 1]);
+ if (ttisstring(&p->k[b])) {
+ *name = svalue(&p->k[b]);
+ return "constant";
+ }
+ break;
+ }
+ case OP_SELF: {
+ int k = GETARG_C(i); /* key index */
+ kname(p, pc, k, name);
+ return "method";
+ }
+ default: break; /* go through to return NULL */
+ }
+ }
+ return NULL; /* could not find reasonable name */
+}
+
+
+/*
+** Try to find a name for a function based on the code that called it.
+** (Only works when function was called by a Lua function.)
+** Returns what the name is (e.g., "for iterator", "method",
+** "metamethod") and sets '*name' to point to the name.
+*/
+static const char *funcnamefromcode (lua_State *L, CallInfo *ci,
+ const char **name) {
+ TMS tm = (TMS)0; /* (initial value avoids warnings) */
+ Proto *p = ci_func(ci)->p; /* calling function */
+ int pc = currentpc(ci); /* calling instruction index */
+ Instruction i = p->code[pc]; /* calling instruction */
+ if (ci->callstatus & CIST_HOOKED) { /* was it called inside a hook? */
+ *name = "?";
+ return "hook";
+ }
+ switch (GET_OPCODE(i)) {
+ case OP_CALL:
+ case OP_TAILCALL:
+ return getobjname(p, pc, GETARG_A(i), name); /* get function name */
+ case OP_TFORCALL: { /* for iterator */
+ *name = "for iterator";
+ return "for iterator";
+ }
+ /* other instructions can do calls through metamethods */
+ case OP_SELF: case OP_GETTABUP: case OP_GETTABLE:
+ tm = TM_INDEX;
+ break;
+ case OP_SETTABUP: case OP_SETTABLE:
+ tm = TM_NEWINDEX;
+ break;
+ case OP_ADD: case OP_SUB: case OP_MUL: case OP_MOD:
+ case OP_POW: case OP_DIV: case OP_IDIV: case OP_BAND:
+ case OP_BOR: case OP_BXOR: case OP_SHL: case OP_SHR: {
+ int offset = cast_int(GET_OPCODE(i)) - cast_int(OP_ADD); /* ORDER OP */
+ tm = cast(TMS, offset + cast_int(TM_ADD)); /* ORDER TM */
+ break;
+ }
+ case OP_UNM: tm = TM_UNM; break;
+ case OP_BNOT: tm = TM_BNOT; break;
+ case OP_LEN: tm = TM_LEN; break;
+ case OP_CONCAT: tm = TM_CONCAT; break;
+ case OP_EQ: tm = TM_EQ; break;
+ case OP_LT: tm = TM_LT; break;
+ case OP_LE: tm = TM_LE; break;
+ default:
+ return NULL; /* cannot find a reasonable name */
+ }
+ *name = getstr(G(L)->tmname[tm]);
+ return "metamethod";
+}
+
+/* }====================================================== */
+
+
+
+/*
+** The subtraction of two potentially unrelated pointers is
+** not ISO C, but it should not crash a program; the subsequent
+** checks are ISO C and ensure a correct result.
+*/
+static int isinstack (CallInfo *ci, const TValue *o) {
+ ptrdiff_t i = o - ci->u.l.base;
+ return (0 <= i && i < (ci->top - ci->u.l.base) && ci->u.l.base + i == o);
+}
+
+
+/*
+** Checks whether value 'o' came from an upvalue. (That can only happen
+** with instructions OP_GETTABUP/OP_SETTABUP, which operate directly on
+** upvalues.)
+*/
+static const char *getupvalname (CallInfo *ci, const TValue *o,
+ const char **name) {
+ LClosure *c = ci_func(ci);
+ int i;
+ for (i = 0; i < c->nupvalues; i++) {
+ if (c->upvals[i]->v == o) {
+ *name = upvalname(c->p, i);
+ return "upvalue";
+ }
+ }
+ return NULL;
+}
+
+
+static const char *varinfo (lua_State *L, const TValue *o) {
+ const char *name = NULL; /* to avoid warnings */
+ CallInfo *ci = L->ci;
+ const char *kind = NULL;
+ if (isLua(ci)) {
+ kind = getupvalname(ci, o, &name); /* check whether 'o' is an upvalue */
+ if (!kind && isinstack(ci, o)) /* no? try a register */
+ kind = getobjname(ci_func(ci)->p, currentpc(ci),
+ cast_int(o - ci->u.l.base), &name);
+ }
+ return (kind) ? luaO_pushfstring(L, " (%s '%s')", kind, name) : "";
+}
+
+
+l_noret luaG_typeerror (lua_State *L, const TValue *o, const char *op) {
+ const char *t = luaT_objtypename(L, o);
+ luaG_runerror(L, "attempt to %s a %s value%s", op, t, varinfo(L, o));
+}
+
+
+l_noret luaG_concaterror (lua_State *L, const TValue *p1, const TValue *p2) {
+ if (ttisstring(p1) || cvt2str(p1)) p1 = p2;
+ luaG_typeerror(L, p1, "concatenate");
+}
+
+
+l_noret luaG_opinterror (lua_State *L, const TValue *p1,
+ const TValue *p2, const char *msg) {
+ lua_Number temp;
+ if (!tonumber(p1, &temp)) /* first operand is wrong? */
+ p2 = p1; /* now second is wrong */
+ luaG_typeerror(L, p2, msg);
+}
+
+
+/*
+** Error when both values are convertible to numbers, but not to integers
+*/
+l_noret luaG_tointerror (lua_State *L, const TValue *p1, const TValue *p2) {
+ lua_Integer temp;
+ if (!tointeger(p1, &temp))
+ p2 = p1;
+ luaG_runerror(L, "number%s has no integer representation", varinfo(L, p2));
+}
+
+
+l_noret luaG_ordererror (lua_State *L, const TValue *p1, const TValue *p2) {
+ const char *t1 = luaT_objtypename(L, p1);
+ const char *t2 = luaT_objtypename(L, p2);
+ if (strcmp(t1, t2) == 0)
+ luaG_runerror(L, "attempt to compare two %s values", t1);
+ else
+ luaG_runerror(L, "attempt to compare %s with %s", t1, t2);
+}
+
+
+/* add src:line information to 'msg' */
+const char *luaG_addinfo (lua_State *L, const char *msg, TString *src,
+ int line) {
+ char buff[LUA_IDSIZE];
+ if (src)
+ luaO_chunkid(buff, getstr(src), LUA_IDSIZE);
+ else { /* no source available; use "?" instead */
+ buff[0] = '?'; buff[1] = '\0';
+ }
+ return luaO_pushfstring(L, "%s:%d: %s", buff, line, msg);
+}
+
+
+l_noret luaG_errormsg (lua_State *L) {
+ if (L->errfunc != 0) { /* is there an error handling function? */
+ StkId errfunc = restorestack(L, L->errfunc);
+ setobjs2s(L, L->top, L->top - 1); /* move argument */
+ setobjs2s(L, L->top - 1, errfunc); /* push function */
+ L->top++; /* assume EXTRA_STACK */
+ luaD_callnoyield(L, L->top - 2, 1); /* call it */
+ }
+ luaD_throw(L, LUA_ERRRUN);
+}
+
+
+l_noret luaG_runerror (lua_State *L, const char *fmt, ...) {
+ CallInfo *ci = L->ci;
+ const char *msg;
+ va_list argp;
+ luaC_checkGC(L); /* error message uses memory */
+ va_start(argp, fmt);
+ msg = luaO_pushvfstring(L, fmt, argp); /* format message */
+ va_end(argp);
+ if (isLua(ci)) /* if Lua function, add source:line information */
+ luaG_addinfo(L, msg, ci_func(ci)->p->source, currentline(ci));
+ luaG_errormsg(L);
+}
+
+
+void luaG_traceexec (lua_State *L) {
+ CallInfo *ci = L->ci;
+ lu_byte mask = L->hookmask;
+ int counthook = (--L->hookcount == 0 && (mask & LUA_MASKCOUNT));
+ if (counthook)
+ resethookcount(L); /* reset count */
+ else if (!(mask & LUA_MASKLINE))
+ return; /* no line hook and count != 0; nothing to be done */
+ if (ci->callstatus & CIST_HOOKYIELD) { /* called hook last time? */
+ ci->callstatus &= ~CIST_HOOKYIELD; /* erase mark */
+ return; /* do not call hook again (VM yielded, so it did not move) */
+ }
+ if (counthook)
+ luaD_hook(L, LUA_HOOKCOUNT, -1); /* call count hook */
+ if (mask & LUA_MASKLINE) {
+ Proto *p = ci_func(ci)->p;
+ int npc = pcRel(ci->u.l.savedpc, p);
+ int newline = getfuncline(p, npc);
+ if (npc == 0 || /* call linehook when enter a new function, */
+ ci->u.l.savedpc <= L->oldpc || /* when jump back (loop), or when */
+ newline != getfuncline(p, pcRel(L->oldpc, p))) /* enter a new line */
+ luaD_hook(L, LUA_HOOKLINE, newline); /* call line hook */
+ }
+ L->oldpc = ci->u.l.savedpc;
+ if (L->status == LUA_YIELD) { /* did hook yield? */
+ if (counthook)
+ L->hookcount = 1; /* undo decrement to zero */
+ ci->u.l.savedpc--; /* undo increment (resume will increment it again) */
+ ci->callstatus |= CIST_HOOKYIELD; /* mark that it yielded */
+ ci->func = L->top - 1; /* protect stack below results */
+ luaD_throw(L, LUA_YIELD);
+ }
+}
+