ba8b5c17 |
1 | /* |
2 | ** $Id: ldebug.c,v 2.90 2012/08/16 17:34:28 roberto Exp $ |
3 | ** Debug Interface |
4 | ** See Copyright Notice in lua.h |
5 | */ |
6 | |
7 | |
8 | #include <stdarg.h> |
9 | #include <stddef.h> |
10 | #include <string.h> |
11 | |
12 | |
13 | #define ldebug_c |
14 | #define LUA_CORE |
15 | |
16 | #include "lua.h" |
17 | |
18 | #include "lapi.h" |
19 | #include "lcode.h" |
20 | #include "ldebug.h" |
21 | #include "ldo.h" |
22 | #include "lfunc.h" |
23 | #include "lobject.h" |
24 | #include "lopcodes.h" |
25 | #include "lstate.h" |
26 | #include "lstring.h" |
27 | #include "ltable.h" |
28 | #include "ltm.h" |
29 | #include "lvm.h" |
30 | |
31 | |
32 | |
33 | #define noLuaClosure(f) ((f) == NULL || (f)->c.tt == LUA_TCCL) |
34 | |
35 | |
36 | static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name); |
37 | |
38 | |
39 | static int currentpc (CallInfo *ci) { |
40 | lua_assert(isLua(ci)); |
41 | return pcRel(ci->u.l.savedpc, ci_func(ci)->p); |
42 | } |
43 | |
44 | |
45 | static int currentline (CallInfo *ci) { |
46 | return getfuncline(ci_func(ci)->p, currentpc(ci)); |
47 | } |
48 | |
49 | |
50 | /* |
51 | ** this function can be called asynchronous (e.g. during a signal) |
52 | */ |
53 | LUA_API int lua_sethook (lua_State *L, lua_Hook func, int mask, int count) { |
54 | if (func == NULL || mask == 0) { /* turn off hooks? */ |
55 | mask = 0; |
56 | func = NULL; |
57 | } |
58 | if (isLua(L->ci)) |
59 | L->oldpc = L->ci->u.l.savedpc; |
60 | L->hook = func; |
61 | L->basehookcount = count; |
62 | resethookcount(L); |
63 | L->hookmask = cast_byte(mask); |
64 | return 1; |
65 | } |
66 | |
67 | |
68 | LUA_API lua_Hook lua_gethook (lua_State *L) { |
69 | return L->hook; |
70 | } |
71 | |
72 | |
73 | LUA_API int lua_gethookmask (lua_State *L) { |
74 | return L->hookmask; |
75 | } |
76 | |
77 | |
78 | LUA_API int lua_gethookcount (lua_State *L) { |
79 | return L->basehookcount; |
80 | } |
81 | |
82 | |
83 | LUA_API int lua_getstack (lua_State *L, int level, lua_Debug *ar) { |
84 | int status; |
85 | CallInfo *ci; |
86 | if (level < 0) return 0; /* invalid (negative) level */ |
87 | lua_lock(L); |
88 | for (ci = L->ci; level > 0 && ci != &L->base_ci; ci = ci->previous) |
89 | level--; |
90 | if (level == 0 && ci != &L->base_ci) { /* level found? */ |
91 | status = 1; |
92 | ar->i_ci = ci; |
93 | } |
94 | else status = 0; /* no such level */ |
95 | lua_unlock(L); |
96 | return status; |
97 | } |
98 | |
99 | |
100 | static const char *upvalname (Proto *p, int uv) { |
101 | TString *s = check_exp(uv < p->sizeupvalues, p->upvalues[uv].name); |
102 | if (s == NULL) return "?"; |
103 | else return getstr(s); |
104 | } |
105 | |
106 | |
107 | static const char *findvararg (CallInfo *ci, int n, StkId *pos) { |
108 | int nparams = clLvalue(ci->func)->p->numparams; |
109 | if (n >= ci->u.l.base - ci->func - nparams) |
110 | return NULL; /* no such vararg */ |
111 | else { |
112 | *pos = ci->func + nparams + n; |
113 | return "(*vararg)"; /* generic name for any vararg */ |
114 | } |
115 | } |
116 | |
117 | |
118 | static const char *findlocal (lua_State *L, CallInfo *ci, int n, |
119 | StkId *pos) { |
120 | const char *name = NULL; |
121 | StkId base; |
122 | if (isLua(ci)) { |
123 | if (n < 0) /* access to vararg values? */ |
124 | return findvararg(ci, -n, pos); |
125 | else { |
126 | base = ci->u.l.base; |
127 | name = luaF_getlocalname(ci_func(ci)->p, n, currentpc(ci)); |
128 | } |
129 | } |
130 | else |
131 | base = ci->func + 1; |
132 | if (name == NULL) { /* no 'standard' name? */ |
133 | StkId limit = (ci == L->ci) ? L->top : ci->next->func; |
134 | if (limit - base >= n && n > 0) /* is 'n' inside 'ci' stack? */ |
135 | name = "(*temporary)"; /* generic name for any valid slot */ |
136 | else |
137 | return NULL; /* no name */ |
138 | } |
139 | *pos = base + (n - 1); |
140 | return name; |
141 | } |
142 | |
143 | |
144 | LUA_API const char *lua_getlocal (lua_State *L, const lua_Debug *ar, int n) { |
145 | const char *name; |
146 | lua_lock(L); |
147 | if (ar == NULL) { /* information about non-active function? */ |
148 | if (!isLfunction(L->top - 1)) /* not a Lua function? */ |
149 | name = NULL; |
150 | else /* consider live variables at function start (parameters) */ |
151 | name = luaF_getlocalname(clLvalue(L->top - 1)->p, n, 0); |
152 | } |
153 | else { /* active function; get information through 'ar' */ |
154 | StkId pos = 0; /* to avoid warnings */ |
155 | name = findlocal(L, ar->i_ci, n, &pos); |
156 | if (name) { |
157 | setobj2s(L, L->top, pos); |
158 | api_incr_top(L); |
159 | } |
160 | } |
161 | lua_unlock(L); |
162 | return name; |
163 | } |
164 | |
165 | |
166 | LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n) { |
167 | StkId pos = 0; /* to avoid warnings */ |
168 | const char *name = findlocal(L, ar->i_ci, n, &pos); |
169 | lua_lock(L); |
170 | if (name) |
171 | setobjs2s(L, pos, L->top - 1); |
172 | L->top--; /* pop value */ |
173 | lua_unlock(L); |
174 | return name; |
175 | } |
176 | |
177 | |
178 | static void funcinfo (lua_Debug *ar, Closure *cl) { |
179 | if (noLuaClosure(cl)) { |
180 | ar->source = "=[C]"; |
181 | ar->linedefined = -1; |
182 | ar->lastlinedefined = -1; |
183 | ar->what = "C"; |
184 | } |
185 | else { |
186 | Proto *p = cl->l.p; |
187 | ar->source = p->source ? getstr(p->source) : "=?"; |
188 | ar->linedefined = p->linedefined; |
189 | ar->lastlinedefined = p->lastlinedefined; |
190 | ar->what = (ar->linedefined == 0) ? "main" : "Lua"; |
191 | } |
192 | luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE); |
193 | } |
194 | |
195 | |
196 | static void collectvalidlines (lua_State *L, Closure *f) { |
197 | if (noLuaClosure(f)) { |
198 | setnilvalue(L->top); |
199 | api_incr_top(L); |
200 | } |
201 | else { |
202 | int i; |
203 | TValue v; |
204 | int *lineinfo = f->l.p->lineinfo; |
205 | Table *t = luaH_new(L); /* new table to store active lines */ |
206 | sethvalue(L, L->top, t); /* push it on stack */ |
207 | api_incr_top(L); |
208 | setbvalue(&v, 1); /* boolean 'true' to be the value of all indices */ |
209 | for (i = 0; i < f->l.p->sizelineinfo; i++) /* for all lines with code */ |
210 | luaH_setint(L, t, lineinfo[i], &v); /* table[line] = true */ |
211 | } |
212 | } |
213 | |
214 | |
215 | static int auxgetinfo (lua_State *L, const char *what, lua_Debug *ar, |
216 | Closure *f, CallInfo *ci) { |
217 | int status = 1; |
218 | for (; *what; what++) { |
219 | switch (*what) { |
220 | case 'S': { |
221 | funcinfo(ar, f); |
222 | break; |
223 | } |
224 | case 'l': { |
225 | ar->currentline = (ci && isLua(ci)) ? currentline(ci) : -1; |
226 | break; |
227 | } |
228 | case 'u': { |
229 | ar->nups = (f == NULL) ? 0 : f->c.nupvalues; |
230 | if (noLuaClosure(f)) { |
231 | ar->isvararg = 1; |
232 | ar->nparams = 0; |
233 | } |
234 | else { |
235 | ar->isvararg = f->l.p->is_vararg; |
236 | ar->nparams = f->l.p->numparams; |
237 | } |
238 | break; |
239 | } |
240 | case 't': { |
241 | ar->istailcall = (ci) ? ci->callstatus & CIST_TAIL : 0; |
242 | break; |
243 | } |
244 | case 'n': { |
245 | /* calling function is a known Lua function? */ |
246 | if (ci && !(ci->callstatus & CIST_TAIL) && isLua(ci->previous)) |
247 | ar->namewhat = getfuncname(L, ci->previous, &ar->name); |
248 | else |
249 | ar->namewhat = NULL; |
250 | if (ar->namewhat == NULL) { |
251 | ar->namewhat = ""; /* not found */ |
252 | ar->name = NULL; |
253 | } |
254 | break; |
255 | } |
256 | case 'L': |
257 | case 'f': /* handled by lua_getinfo */ |
258 | break; |
259 | default: status = 0; /* invalid option */ |
260 | } |
261 | } |
262 | return status; |
263 | } |
264 | |
265 | |
266 | LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) { |
267 | int status; |
268 | Closure *cl; |
269 | CallInfo *ci; |
270 | StkId func; |
271 | lua_lock(L); |
272 | if (*what == '>') { |
273 | ci = NULL; |
274 | func = L->top - 1; |
275 | api_check(L, ttisfunction(func), "function expected"); |
276 | what++; /* skip the '>' */ |
277 | L->top--; /* pop function */ |
278 | } |
279 | else { |
280 | ci = ar->i_ci; |
281 | func = ci->func; |
282 | lua_assert(ttisfunction(ci->func)); |
283 | } |
284 | cl = ttisclosure(func) ? clvalue(func) : NULL; |
285 | status = auxgetinfo(L, what, ar, cl, ci); |
286 | if (strchr(what, 'f')) { |
287 | setobjs2s(L, L->top, func); |
288 | api_incr_top(L); |
289 | } |
290 | if (strchr(what, 'L')) |
291 | collectvalidlines(L, cl); |
292 | lua_unlock(L); |
293 | return status; |
294 | } |
295 | |
296 | |
297 | /* |
298 | ** {====================================================== |
299 | ** Symbolic Execution |
300 | ** ======================================================= |
301 | */ |
302 | |
303 | static const char *getobjname (Proto *p, int lastpc, int reg, |
304 | const char **name); |
305 | |
306 | |
307 | /* |
308 | ** find a "name" for the RK value 'c' |
309 | */ |
310 | static void kname (Proto *p, int pc, int c, const char **name) { |
311 | if (ISK(c)) { /* is 'c' a constant? */ |
312 | TValue *kvalue = &p->k[INDEXK(c)]; |
313 | if (ttisstring(kvalue)) { /* literal constant? */ |
314 | *name = svalue(kvalue); /* it is its own name */ |
315 | return; |
316 | } |
317 | /* else no reasonable name found */ |
318 | } |
319 | else { /* 'c' is a register */ |
320 | const char *what = getobjname(p, pc, c, name); /* search for 'c' */ |
321 | if (what && *what == 'c') { /* found a constant name? */ |
322 | return; /* 'name' already filled */ |
323 | } |
324 | /* else no reasonable name found */ |
325 | } |
326 | *name = "?"; /* no reasonable name found */ |
327 | } |
328 | |
329 | |
330 | /* |
331 | ** try to find last instruction before 'lastpc' that modified register 'reg' |
332 | */ |
333 | static int findsetreg (Proto *p, int lastpc, int reg) { |
334 | int pc; |
335 | int setreg = -1; /* keep last instruction that changed 'reg' */ |
336 | for (pc = 0; pc < lastpc; pc++) { |
337 | Instruction i = p->code[pc]; |
338 | OpCode op = GET_OPCODE(i); |
339 | int a = GETARG_A(i); |
340 | switch (op) { |
341 | case OP_LOADNIL: { |
342 | int b = GETARG_B(i); |
343 | if (a <= reg && reg <= a + b) /* set registers from 'a' to 'a+b' */ |
344 | setreg = pc; |
345 | break; |
346 | } |
347 | case OP_TFORCALL: { |
348 | if (reg >= a + 2) setreg = pc; /* affect all regs above its base */ |
349 | break; |
350 | } |
351 | case OP_CALL: |
352 | case OP_TAILCALL: { |
353 | if (reg >= a) setreg = pc; /* affect all registers above base */ |
354 | break; |
355 | } |
356 | case OP_JMP: { |
357 | int b = GETARG_sBx(i); |
358 | int dest = pc + 1 + b; |
359 | /* jump is forward and do not skip `lastpc'? */ |
360 | if (pc < dest && dest <= lastpc) |
361 | pc += b; /* do the jump */ |
362 | break; |
363 | } |
364 | case OP_TEST: { |
365 | if (reg == a) setreg = pc; /* jumped code can change 'a' */ |
366 | break; |
367 | } |
368 | default: |
369 | if (testAMode(op) && reg == a) /* any instruction that set A */ |
370 | setreg = pc; |
371 | break; |
372 | } |
373 | } |
374 | return setreg; |
375 | } |
376 | |
377 | |
378 | static const char *getobjname (Proto *p, int lastpc, int reg, |
379 | const char **name) { |
380 | int pc; |
381 | *name = luaF_getlocalname(p, reg + 1, lastpc); |
382 | if (*name) /* is a local? */ |
383 | return "local"; |
384 | /* else try symbolic execution */ |
385 | pc = findsetreg(p, lastpc, reg); |
386 | if (pc != -1) { /* could find instruction? */ |
387 | Instruction i = p->code[pc]; |
388 | OpCode op = GET_OPCODE(i); |
389 | switch (op) { |
390 | case OP_MOVE: { |
391 | int b = GETARG_B(i); /* move from 'b' to 'a' */ |
392 | if (b < GETARG_A(i)) |
393 | return getobjname(p, pc, b, name); /* get name for 'b' */ |
394 | break; |
395 | } |
396 | case OP_GETTABUP: |
397 | case OP_GETTABLE: { |
398 | int k = GETARG_C(i); /* key index */ |
399 | int t = GETARG_B(i); /* table index */ |
400 | const char *vn = (op == OP_GETTABLE) /* name of indexed variable */ |
401 | ? luaF_getlocalname(p, t + 1, pc) |
402 | : upvalname(p, t); |
403 | kname(p, pc, k, name); |
404 | return (vn && strcmp(vn, LUA_ENV) == 0) ? "global" : "field"; |
405 | } |
406 | case OP_GETUPVAL: { |
407 | *name = upvalname(p, GETARG_B(i)); |
408 | return "upvalue"; |
409 | } |
410 | case OP_LOADK: |
411 | case OP_LOADKX: { |
412 | int b = (op == OP_LOADK) ? GETARG_Bx(i) |
413 | : GETARG_Ax(p->code[pc + 1]); |
414 | if (ttisstring(&p->k[b])) { |
415 | *name = svalue(&p->k[b]); |
416 | return "constant"; |
417 | } |
418 | break; |
419 | } |
420 | case OP_SELF: { |
421 | int k = GETARG_C(i); /* key index */ |
422 | kname(p, pc, k, name); |
423 | return "method"; |
424 | } |
425 | default: break; /* go through to return NULL */ |
426 | } |
427 | } |
428 | return NULL; /* could not find reasonable name */ |
429 | } |
430 | |
431 | |
432 | static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name) { |
433 | TMS tm; |
434 | Proto *p = ci_func(ci)->p; /* calling function */ |
435 | int pc = currentpc(ci); /* calling instruction index */ |
436 | Instruction i = p->code[pc]; /* calling instruction */ |
437 | switch (GET_OPCODE(i)) { |
438 | case OP_CALL: |
439 | case OP_TAILCALL: /* get function name */ |
440 | return getobjname(p, pc, GETARG_A(i), name); |
441 | case OP_TFORCALL: { /* for iterator */ |
442 | *name = "for iterator"; |
443 | return "for iterator"; |
444 | } |
445 | /* all other instructions can call only through metamethods */ |
446 | case OP_SELF: |
447 | case OP_GETTABUP: |
448 | case OP_GETTABLE: tm = TM_INDEX; break; |
449 | case OP_SETTABUP: |
450 | case OP_SETTABLE: tm = TM_NEWINDEX; break; |
451 | case OP_EQ: tm = TM_EQ; break; |
452 | case OP_ADD: tm = TM_ADD; break; |
453 | case OP_SUB: tm = TM_SUB; break; |
454 | case OP_MUL: tm = TM_MUL; break; |
455 | case OP_DIV: tm = TM_DIV; break; |
456 | case OP_MOD: tm = TM_MOD; break; |
457 | case OP_POW: tm = TM_POW; break; |
458 | case OP_UNM: tm = TM_UNM; break; |
459 | case OP_LEN: tm = TM_LEN; break; |
460 | case OP_LT: tm = TM_LT; break; |
461 | case OP_LE: tm = TM_LE; break; |
462 | case OP_CONCAT: tm = TM_CONCAT; break; |
463 | default: |
464 | return NULL; /* else no useful name can be found */ |
465 | } |
466 | *name = getstr(G(L)->tmname[tm]); |
467 | return "metamethod"; |
468 | } |
469 | |
470 | /* }====================================================== */ |
471 | |
472 | |
473 | |
474 | /* |
475 | ** only ANSI way to check whether a pointer points to an array |
476 | ** (used only for error messages, so efficiency is not a big concern) |
477 | */ |
478 | static int isinstack (CallInfo *ci, const TValue *o) { |
479 | StkId p; |
480 | for (p = ci->u.l.base; p < ci->top; p++) |
481 | if (o == p) return 1; |
482 | return 0; |
483 | } |
484 | |
485 | |
486 | static const char *getupvalname (CallInfo *ci, const TValue *o, |
487 | const char **name) { |
488 | LClosure *c = ci_func(ci); |
489 | int i; |
490 | for (i = 0; i < c->nupvalues; i++) { |
491 | if (c->upvals[i]->v == o) { |
492 | *name = upvalname(c->p, i); |
493 | return "upvalue"; |
494 | } |
495 | } |
496 | return NULL; |
497 | } |
498 | |
499 | |
500 | l_noret luaG_typeerror (lua_State *L, const TValue *o, const char *op) { |
501 | CallInfo *ci = L->ci; |
502 | const char *name = NULL; |
503 | const char *t = objtypename(o); |
504 | const char *kind = NULL; |
505 | if (isLua(ci)) { |
506 | kind = getupvalname(ci, o, &name); /* check whether 'o' is an upvalue */ |
507 | if (!kind && isinstack(ci, o)) /* no? try a register */ |
508 | kind = getobjname(ci_func(ci)->p, currentpc(ci), |
509 | cast_int(o - ci->u.l.base), &name); |
510 | } |
511 | if (kind) |
512 | luaG_runerror(L, "attempt to %s %s " LUA_QS " (a %s value)", |
513 | op, kind, name, t); |
514 | else |
515 | luaG_runerror(L, "attempt to %s a %s value", op, t); |
516 | } |
517 | |
518 | |
519 | l_noret luaG_concaterror (lua_State *L, StkId p1, StkId p2) { |
520 | if (ttisstring(p1) || ttisnumber(p1)) p1 = p2; |
521 | lua_assert(!ttisstring(p1) && !ttisnumber(p2)); |
522 | luaG_typeerror(L, p1, "concatenate"); |
523 | } |
524 | |
525 | |
526 | l_noret luaG_aritherror (lua_State *L, const TValue *p1, const TValue *p2) { |
527 | TValue temp; |
528 | if (luaV_tonumber(p1, &temp) == NULL) |
529 | p2 = p1; /* first operand is wrong */ |
530 | luaG_typeerror(L, p2, "perform arithmetic on"); |
531 | } |
532 | |
533 | |
534 | l_noret luaG_ordererror (lua_State *L, const TValue *p1, const TValue *p2) { |
535 | const char *t1 = objtypename(p1); |
536 | const char *t2 = objtypename(p2); |
537 | if (t1 == t2) |
538 | luaG_runerror(L, "attempt to compare two %s values", t1); |
539 | else |
540 | luaG_runerror(L, "attempt to compare %s with %s", t1, t2); |
541 | } |
542 | |
543 | |
544 | static void addinfo (lua_State *L, const char *msg) { |
545 | CallInfo *ci = L->ci; |
546 | if (isLua(ci)) { /* is Lua code? */ |
547 | char buff[LUA_IDSIZE]; /* add file:line information */ |
548 | int line = currentline(ci); |
549 | TString *src = ci_func(ci)->p->source; |
550 | if (src) |
551 | luaO_chunkid(buff, getstr(src), LUA_IDSIZE); |
552 | else { /* no source available; use "?" instead */ |
553 | buff[0] = '?'; buff[1] = '\0'; |
554 | } |
555 | luaO_pushfstring(L, "%s:%d: %s", buff, line, msg); |
556 | } |
557 | } |
558 | |
559 | |
560 | l_noret luaG_errormsg (lua_State *L) { |
561 | if (L->errfunc != 0) { /* is there an error handling function? */ |
562 | StkId errfunc = restorestack(L, L->errfunc); |
563 | if (!ttisfunction(errfunc)) luaD_throw(L, LUA_ERRERR); |
564 | setobjs2s(L, L->top, L->top - 1); /* move argument */ |
565 | setobjs2s(L, L->top - 1, errfunc); /* push function */ |
566 | L->top++; |
567 | luaD_call(L, L->top - 2, 1, 0); /* call it */ |
568 | } |
569 | luaD_throw(L, LUA_ERRRUN); |
570 | } |
571 | |
572 | |
573 | l_noret luaG_runerror (lua_State *L, const char *fmt, ...) { |
574 | va_list argp; |
575 | va_start(argp, fmt); |
576 | addinfo(L, luaO_pushvfstring(L, fmt, argp)); |
577 | va_end(argp); |
578 | luaG_errormsg(L); |
579 | } |
580 | |