2 ** $Id: ldebug.c,v 2.29.1.6 2008/05/08 16:56:26 roberto Exp $
4 ** See Copyright Notice in lua.h
33 static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name);
36 static int currentpc (lua_State *L, CallInfo *ci) {
37 if (!isLua(ci)) return -1; /* function is not a Lua function? */
39 ci->savedpc = L->savedpc;
40 return pcRel(ci->savedpc, ci_func(ci)->l.p);
44 static int currentline (lua_State *L, CallInfo *ci) {
45 int pc = currentpc(L, ci);
47 return -1; /* only active lua functions have current-line information */
49 return getline(ci_func(ci)->l.p, pc);
54 ** this function can be called asynchronous (e.g. during a signal)
56 LUA_API int lua_sethook (lua_State *L, lua_Hook func, int mask, int count) {
57 if (func == NULL || mask == 0) { /* turn off hooks? */
62 L->basehookcount = count;
64 L->hookmask = cast_byte(mask);
69 LUA_API lua_Hook lua_gethook (lua_State *L) {
74 LUA_API int lua_gethookmask (lua_State *L) {
79 LUA_API int lua_gethookcount (lua_State *L) {
80 return L->basehookcount;
84 LUA_API int lua_getstack (lua_State *L, int level, lua_Debug *ar) {
88 for (ci = L->ci; level > 0 && ci > L->base_ci; ci--) {
90 if (f_isLua(ci)) /* Lua function? */
91 level -= ci->tailcalls; /* skip lost tail calls */
93 if (level == 0 && ci > L->base_ci) { /* level found? */
95 ar->i_ci = cast_int(ci - L->base_ci);
97 else if (level < 0) { /* level is of a lost tail call? */
101 else status = 0; /* no such level */
107 static Proto *getluaproto (CallInfo *ci) {
108 return (isLua(ci) ? ci_func(ci)->l.p : NULL);
112 static const char *findlocal (lua_State *L, CallInfo *ci, int n) {
114 Proto *fp = getluaproto(ci);
115 if (fp && (name = luaF_getlocalname(fp, n, currentpc(L, ci))) != NULL)
116 return name; /* is a local variable in a Lua function */
118 StkId limit = (ci == L->ci) ? L->top : (ci+1)->func;
119 if (limit - ci->base >= n && n > 0) /* is 'n' inside 'ci' stack? */
120 return "(*temporary)";
127 LUA_API const char *lua_getlocal (lua_State *L, const lua_Debug *ar, int n) {
128 CallInfo *ci = L->base_ci + ar->i_ci;
129 const char *name = findlocal(L, ci, n);
132 luaA_pushobject(L, ci->base + (n - 1));
138 LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n) {
139 CallInfo *ci = L->base_ci + ar->i_ci;
140 const char *name = findlocal(L, ci, n);
143 setobjs2s(L, ci->base + (n - 1), L->top - 1);
144 L->top--; /* pop value */
150 static void funcinfo (lua_Debug *ar, Closure *cl) {
153 ar->linedefined = -1;
154 ar->lastlinedefined = -1;
158 ar->source = getstr(cl->l.p->source);
159 ar->linedefined = cl->l.p->linedefined;
160 ar->lastlinedefined = cl->l.p->lastlinedefined;
161 ar->what = (ar->linedefined == 0) ? "main" : "Lua";
163 luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE);
167 static void info_tailcall (lua_Debug *ar) {
168 ar->name = ar->namewhat = "";
170 ar->lastlinedefined = ar->linedefined = ar->currentline = -1;
171 ar->source = "=(tail call)";
172 luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE);
177 static void collectvalidlines (lua_State *L, Closure *f) {
178 if (f == NULL || f->c.isC) {
182 Table *t = luaH_new(L, 0, 0);
183 int *lineinfo = f->l.p->lineinfo;
185 for (i=0; i<f->l.p->sizelineinfo; i++)
186 setbvalue(luaH_setnum(L, t, lineinfo[i]), 1);
187 sethvalue(L, L->top, t);
193 static int auxgetinfo (lua_State *L, const char *what, lua_Debug *ar,
194 Closure *f, CallInfo *ci) {
200 for (; *what; what++) {
207 ar->currentline = (ci) ? currentline(L, ci) : -1;
211 ar->nups = f->c.nupvalues;
215 ar->namewhat = (ci) ? getfuncname(L, ci, &ar->name) : NULL;
216 if (ar->namewhat == NULL) {
217 ar->namewhat = ""; /* not found */
223 case 'f': /* handled by lua_getinfo */
225 default: status = 0; /* invalid option */
232 LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) {
238 StkId func = L->top - 1;
239 luai_apicheck(L, ttisfunction(func));
240 what++; /* skip the '>' */
242 L->top--; /* pop function */
244 else if (ar->i_ci != 0) { /* no tail call? */
245 ci = L->base_ci + ar->i_ci;
246 lua_assert(ttisfunction(ci->func));
247 f = clvalue(ci->func);
249 status = auxgetinfo(L, what, ar, f, ci);
250 if (strchr(what, 'f')) {
251 if (f == NULL) setnilvalue(L->top);
252 else setclvalue(L, L->top, f);
255 if (strchr(what, 'L'))
256 collectvalidlines(L, f);
263 ** {======================================================
264 ** Symbolic Execution and code checker
265 ** =======================================================
268 #define check(x) if (!(x)) return 0;
270 #define checkjump(pt,pc) check(0 <= pc && pc < pt->sizecode)
272 #define checkreg(pt,reg) check((reg) < (pt)->maxstacksize)
276 static int precheck (const Proto *pt) {
277 check(pt->maxstacksize <= MAXSTACK);
278 check(pt->numparams+(pt->is_vararg & VARARG_HASARG) <= pt->maxstacksize);
279 check(!(pt->is_vararg & VARARG_NEEDSARG) ||
280 (pt->is_vararg & VARARG_HASARG));
281 check(pt->sizeupvalues <= pt->nups);
282 check(pt->sizelineinfo == pt->sizecode || pt->sizelineinfo == 0);
283 check(pt->sizecode > 0 && GET_OPCODE(pt->code[pt->sizecode-1]) == OP_RETURN);
288 #define checkopenop(pt,pc) luaG_checkopenop((pt)->code[(pc)+1])
290 int luaG_checkopenop (Instruction i) {
291 switch (GET_OPCODE(i)) {
296 check(GETARG_B(i) == 0);
299 default: return 0; /* invalid instruction after an open call */
304 static int checkArgMode (const Proto *pt, int r, enum OpArgMask mode) {
306 case OpArgN: check(r == 0); break;
308 case OpArgR: checkreg(pt, r); break;
310 check(ISK(r) ? INDEXK(r) < pt->sizek : r < pt->maxstacksize);
317 static Instruction symbexec (const Proto *pt, int lastpc, int reg) {
319 int last; /* stores position of last instruction that changed `reg' */
320 last = pt->sizecode-1; /* points to final return (a `neutral' instruction) */
322 for (pc = 0; pc < lastpc; pc++) {
323 Instruction i = pt->code[pc];
324 OpCode op = GET_OPCODE(i);
328 check(op < NUM_OPCODES);
330 switch (getOpMode(op)) {
334 check(checkArgMode(pt, b, getBMode(op)));
335 check(checkArgMode(pt, c, getCMode(op)));
340 if (getBMode(op) == OpArgK) check(b < pt->sizek);
345 if (getBMode(op) == OpArgR) {
347 check(0 <= dest && dest < pt->sizecode);
350 /* check that it does not jump to a setlist count; this
351 is tricky, because the count from a previous setlist may
352 have the same value of an invalid setlist; so, we must
353 go all the way back to the first of them (if any) */
354 for (j = 0; j < dest; j++) {
355 Instruction d = pt->code[dest-1-j];
356 if (!(GET_OPCODE(d) == OP_SETLIST && GETARG_C(d) == 0)) break;
358 /* if 'j' is even, previous value is not a setlist (even if
359 it looks like one) */
367 if (a == reg) last = pc; /* change register `a' */
370 check(pc+2 < pt->sizecode); /* check skip */
371 check(GET_OPCODE(pt->code[pc+1]) == OP_JMP);
375 if (c == 1) { /* does it jump? */
376 check(pc+2 < pt->sizecode); /* check its jump */
377 check(GET_OPCODE(pt->code[pc+1]) != OP_SETLIST ||
378 GETARG_C(pt->code[pc+1]) != 0);
383 if (a <= reg && reg <= b)
384 last = pc; /* set registers from `a' to `b' */
394 check(ttisstring(&pt->k[b]));
399 if (reg == a+1) last = pc;
403 check(b < c); /* at least two operands */
407 check(c >= 1); /* at least one result (control variable) */
408 checkreg(pt, a+2+c); /* space for results */
409 if (reg >= a+2) last = pc; /* affect all regs above its base */
418 /* not full check and jump is forward and do not skip `lastpc'? */
419 if (reg != NO_REG && pc < dest && dest <= lastpc)
420 pc += b; /* do the jump */
428 c--; /* c = num. returns */
429 if (c == LUA_MULTRET) {
430 check(checkopenop(pt, pc));
434 if (reg >= a) last = pc; /* affect all registers above base */
438 b--; /* b = num. returns */
439 if (b > 0) checkreg(pt, a+b-1);
443 if (b > 0) checkreg(pt, a + b);
446 check(pc < pt->sizecode - 1);
452 check(b < pt->sizep);
453 nup = pt->p[b]->nups;
454 check(pc + nup < pt->sizecode);
455 for (j = 1; j <= nup; j++) {
456 OpCode op1 = GET_OPCODE(pt->code[pc + j]);
457 check(op1 == OP_GETUPVAL || op1 == OP_MOVE);
459 if (reg != NO_REG) /* tracing? */
460 pc += nup; /* do not 'execute' these pseudo-instructions */
464 check((pt->is_vararg & VARARG_ISVARARG) &&
465 !(pt->is_vararg & VARARG_NEEDSARG));
467 if (b == LUA_MULTRET) check(checkopenop(pt, pc));
474 return pt->code[last];
481 /* }====================================================== */
484 int luaG_checkcode (const Proto *pt) {
485 return (symbexec(pt, pt->sizecode, NO_REG) != 0);
489 static const char *kname (Proto *p, int c) {
490 if (ISK(c) && ttisstring(&p->k[INDEXK(c)]))
491 return svalue(&p->k[INDEXK(c)]);
497 static const char *getobjname (lua_State *L, CallInfo *ci, int stackpos,
499 if (isLua(ci)) { /* a Lua function? */
500 Proto *p = ci_func(ci)->l.p;
501 int pc = currentpc(L, ci);
503 *name = luaF_getlocalname(p, stackpos+1, pc);
504 if (*name) /* is a local? */
506 i = symbexec(p, pc, stackpos); /* try symbolic execution */
507 lua_assert(pc != -1);
508 switch (GET_OPCODE(i)) {
510 int g = GETARG_Bx(i); /* global index */
511 lua_assert(ttisstring(&p->k[g]));
512 *name = svalue(&p->k[g]);
517 int b = GETARG_B(i); /* move from `b' to `a' */
519 return getobjname(L, ci, b, name); /* get name for `b' */
523 int k = GETARG_C(i); /* key index */
528 int u = GETARG_B(i); /* upvalue index */
529 *name = p->upvalues ? getstr(p->upvalues[u]) : "?";
533 int k = GETARG_C(i); /* key index */
540 return NULL; /* no useful name found */
544 static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name) {
546 if ((isLua(ci) && ci->tailcalls > 0) || !isLua(ci - 1))
547 return NULL; /* calling function is not Lua (or is unknown) */
548 ci--; /* calling function */
549 i = ci_func(ci)->l.p->code[currentpc(L, ci)];
550 if (GET_OPCODE(i) == OP_CALL || GET_OPCODE(i) == OP_TAILCALL ||
551 GET_OPCODE(i) == OP_TFORLOOP)
552 return getobjname(L, ci, GETARG_A(i), name);
554 return NULL; /* no useful name can be found */
558 /* only ANSI way to check whether a pointer points to an array */
559 static int isinstack (CallInfo *ci, const TValue *o) {
561 for (p = ci->base; p < ci->top; p++)
562 if (o == p) return 1;
567 void luaG_typeerror (lua_State *L, const TValue *o, const char *op) {
568 const char *name = NULL;
569 const char *t = luaT_typenames[ttype(o)];
570 const char *kind = (isinstack(L->ci, o)) ?
571 getobjname(L, L->ci, cast_int(o - L->base), &name) :
574 luaG_runerror(L, "attempt to %s %s " LUA_QS " (a %s value)",
577 luaG_runerror(L, "attempt to %s a %s value", op, t);
581 void luaG_concaterror (lua_State *L, StkId p1, StkId p2) {
582 if (ttisstring(p1) || ttisnumber(p1)) p1 = p2;
583 lua_assert(!ttisstring(p1) && !ttisnumber(p1));
584 luaG_typeerror(L, p1, "concatenate");
588 void luaG_aritherror (lua_State *L, const TValue *p1, const TValue *p2) {
590 if (luaV_tonumber(p1, &temp) == NULL)
591 p2 = p1; /* first operand is wrong */
592 luaG_typeerror(L, p2, "perform arithmetic on");
596 int luaG_ordererror (lua_State *L, const TValue *p1, const TValue *p2) {
597 const char *t1 = luaT_typenames[ttype(p1)];
598 const char *t2 = luaT_typenames[ttype(p2)];
600 luaG_runerror(L, "attempt to compare two %s values", t1);
602 luaG_runerror(L, "attempt to compare %s with %s", t1, t2);
607 static void addinfo (lua_State *L, const char *msg) {
608 CallInfo *ci = L->ci;
609 if (isLua(ci)) { /* is Lua code? */
610 char buff[LUA_IDSIZE]; /* add file:line information */
611 int line = currentline(L, ci);
612 luaO_chunkid(buff, getstr(getluaproto(ci)->source), LUA_IDSIZE);
613 luaO_pushfstring(L, "%s:%d: %s", buff, line, msg);
618 void luaG_errormsg (lua_State *L) {
619 if (L->errfunc != 0) { /* is there an error handling function? */
620 StkId errfunc = restorestack(L, L->errfunc);
621 if (!ttisfunction(errfunc)) luaD_throw(L, LUA_ERRERR);
622 setobjs2s(L, L->top, L->top - 1); /* move argument */
623 setobjs2s(L, L->top - 1, errfunc); /* push function */
625 luaD_call(L, L->top - 2, 1); /* call it */
627 luaD_throw(L, LUA_ERRRUN);
631 void luaG_runerror (lua_State *L, const char *fmt, ...) {
634 addinfo(L, luaO_pushvfstring(L, fmt, argp));