PageRenderTime 48ms CodeModel.GetById 1ms app.highlight 41ms RepoModel.GetById 1ms app.codeStats 1ms

/src/middleware/lua/ldebug.c

https://bitbucket.org/vivkin/gam3b00bs/
C | 638 lines | 532 code | 83 blank | 23 comment | 145 complexity | 82c84cf040bf99a5ab821a64b3d17974 MD5 | raw file
  1/*
  2** $Id: ldebug.c,v 2.29.1.6 2008/05/08 16:56:26 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
 33static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name);
 34
 35
 36static int currentpc (lua_State *L, CallInfo *ci) {
 37  if (!isLua(ci)) return -1;  /* function is not a Lua function? */
 38  if (ci == L->ci)
 39    ci->savedpc = L->savedpc;
 40  return pcRel(ci->savedpc, ci_func(ci)->l.p);
 41}
 42
 43
 44static int currentline (lua_State *L, CallInfo *ci) {
 45  int pc = currentpc(L, ci);
 46  if (pc < 0)
 47    return -1;  /* only active lua functions have current-line information */
 48  else
 49    return getline(ci_func(ci)->l.p, pc);
 50}
 51
 52
 53/*
 54** this function can be called asynchronous (e.g. during a signal)
 55*/
 56LUA_API int lua_sethook (lua_State *L, lua_Hook func, int mask, int count) {
 57  if (func == NULL || mask == 0) {  /* turn off hooks? */
 58    mask = 0;
 59    func = NULL;
 60  }
 61  L->hook = func;
 62  L->basehookcount = count;
 63  resethookcount(L);
 64  L->hookmask = cast_byte(mask);
 65  return 1;
 66}
 67
 68
 69LUA_API lua_Hook lua_gethook (lua_State *L) {
 70  return L->hook;
 71}
 72
 73
 74LUA_API int lua_gethookmask (lua_State *L) {
 75  return L->hookmask;
 76}
 77
 78
 79LUA_API int lua_gethookcount (lua_State *L) {
 80  return L->basehookcount;
 81}
 82
 83
 84LUA_API int lua_getstack (lua_State *L, int level, lua_Debug *ar) {
 85  int status;
 86  CallInfo *ci;
 87  lua_lock(L);
 88  for (ci = L->ci; level > 0 && ci > L->base_ci; ci--) {
 89    level--;
 90    if (f_isLua(ci))  /* Lua function? */
 91      level -= ci->tailcalls;  /* skip lost tail calls */
 92  }
 93  if (level == 0 && ci > L->base_ci) {  /* level found? */
 94    status = 1;
 95    ar->i_ci = cast_int(ci - L->base_ci);
 96  }
 97  else if (level < 0) {  /* level is of a lost tail call? */
 98    status = 1;
 99    ar->i_ci = 0;
100  }
101  else status = 0;  /* no such level */
102  lua_unlock(L);
103  return status;
104}
105
106
107static Proto *getluaproto (CallInfo *ci) {
108  return (isLua(ci) ? ci_func(ci)->l.p : NULL);
109}
110
111
112static const char *findlocal (lua_State *L, CallInfo *ci, int n) {
113  const char *name;
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 */
117  else {
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)";
121    else
122      return NULL;
123  }
124}
125
126
127LUA_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);
130  lua_lock(L);
131  if (name)
132      luaA_pushobject(L, ci->base + (n - 1));
133  lua_unlock(L);
134  return name;
135}
136
137
138LUA_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);
141  lua_lock(L);
142  if (name)
143      setobjs2s(L, ci->base + (n - 1), L->top - 1);
144  L->top--;  /* pop value */
145  lua_unlock(L);
146  return name;
147}
148
149
150static void funcinfo (lua_Debug *ar, Closure *cl) {
151  if (cl->c.isC) {
152    ar->source = "=[C]";
153    ar->linedefined = -1;
154    ar->lastlinedefined = -1;
155    ar->what = "C";
156  }
157  else {
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";
162  }
163  luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE);
164}
165
166
167static void info_tailcall (lua_Debug *ar) {
168  ar->name = ar->namewhat = "";
169  ar->what = "tail";
170  ar->lastlinedefined = ar->linedefined = ar->currentline = -1;
171  ar->source = "=(tail call)";
172  luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE);
173  ar->nups = 0;
174}
175
176
177static void collectvalidlines (lua_State *L, Closure *f) {
178  if (f == NULL || f->c.isC) {
179    setnilvalue(L->top);
180  }
181  else {
182    Table *t = luaH_new(L, 0, 0);
183    int *lineinfo = f->l.p->lineinfo;
184    int i;
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); 
188  }
189  incr_top(L);
190}
191
192
193static int auxgetinfo (lua_State *L, const char *what, lua_Debug *ar,
194                    Closure *f, CallInfo *ci) {
195  int status = 1;
196  if (f == NULL) {
197    info_tailcall(ar);
198    return status;
199  }
200  for (; *what; what++) {
201    switch (*what) {
202      case 'S': {
203        funcinfo(ar, f);
204        break;
205      }
206      case 'l': {
207        ar->currentline = (ci) ? currentline(L, ci) : -1;
208        break;
209      }
210      case 'u': {
211        ar->nups = f->c.nupvalues;
212        break;
213      }
214      case 'n': {
215        ar->namewhat = (ci) ? getfuncname(L, ci, &ar->name) : NULL;
216        if (ar->namewhat == NULL) {
217          ar->namewhat = "";  /* not found */
218          ar->name = NULL;
219        }
220        break;
221      }
222      case 'L':
223      case 'f':  /* handled by lua_getinfo */
224        break;
225      default: status = 0;  /* invalid option */
226    }
227  }
228  return status;
229}
230
231
232LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) {
233  int status;
234  Closure *f = NULL;
235  CallInfo *ci = NULL;
236  lua_lock(L);
237  if (*what == '>') {
238    StkId func = L->top - 1;
239    luai_apicheck(L, ttisfunction(func));
240    what++;  /* skip the '>' */
241    f = clvalue(func);
242    L->top--;  /* pop function */
243  }
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);
248  }
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);
253    incr_top(L);
254  }
255  if (strchr(what, 'L'))
256    collectvalidlines(L, f);
257  lua_unlock(L);
258  return status;
259}
260
261
262/*
263** {======================================================
264** Symbolic Execution and code checker
265** =======================================================
266*/
267
268#define check(x)		if (!(x)) return 0;
269
270#define checkjump(pt,pc)	check(0 <= pc && pc < pt->sizecode)
271
272#define checkreg(pt,reg)	check((reg) < (pt)->maxstacksize)
273
274
275
276static 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);
284  return 1;
285}
286
287
288#define checkopenop(pt,pc)	luaG_checkopenop((pt)->code[(pc)+1])
289
290int luaG_checkopenop (Instruction i) {
291  switch (GET_OPCODE(i)) {
292    case OP_CALL:
293    case OP_TAILCALL:
294    case OP_RETURN:
295    case OP_SETLIST: {
296      check(GETARG_B(i) == 0);
297      return 1;
298    }
299    default: return 0;  /* invalid instruction after an open call */
300  }
301}
302
303
304static int checkArgMode (const Proto *pt, int r, enum OpArgMask mode) {
305  switch (mode) {
306    case OpArgN: check(r == 0); break;
307    case OpArgU: break;
308    case OpArgR: checkreg(pt, r); break;
309    case OpArgK:
310      check(ISK(r) ? INDEXK(r) < pt->sizek : r < pt->maxstacksize);
311      break;
312  }
313  return 1;
314}
315
316
317static Instruction symbexec (const Proto *pt, int lastpc, int reg) {
318  int pc;
319  int last;  /* stores position of last instruction that changed `reg' */
320  last = pt->sizecode-1;  /* points to final return (a `neutral' instruction) */
321  check(precheck(pt));
322  for (pc = 0; pc < lastpc; pc++) {
323    Instruction i = pt->code[pc];
324    OpCode op = GET_OPCODE(i);
325    int a = GETARG_A(i);
326    int b = 0;
327    int c = 0;
328    check(op < NUM_OPCODES);
329    checkreg(pt, a);
330    switch (getOpMode(op)) {
331      case iABC: {
332        b = GETARG_B(i);
333        c = GETARG_C(i);
334        check(checkArgMode(pt, b, getBMode(op)));
335        check(checkArgMode(pt, c, getCMode(op)));
336        break;
337      }
338      case iABx: {
339        b = GETARG_Bx(i);
340        if (getBMode(op) == OpArgK) check(b < pt->sizek);
341        break;
342      }
343      case iAsBx: {
344        b = GETARG_sBx(i);
345        if (getBMode(op) == OpArgR) {
346          int dest = pc+1+b;
347          check(0 <= dest && dest < pt->sizecode);
348          if (dest > 0) {
349            int j;
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;
357            }
358            /* if 'j' is even, previous value is not a setlist (even if
359               it looks like one) */
360            check((j&1) == 0);
361          }
362        }
363        break;
364      }
365    }
366    if (testAMode(op)) {
367      if (a == reg) last = pc;  /* change register `a' */
368    }
369    if (testTMode(op)) {
370      check(pc+2 < pt->sizecode);  /* check skip */
371      check(GET_OPCODE(pt->code[pc+1]) == OP_JMP);
372    }
373    switch (op) {
374      case OP_LOADBOOL: {
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);
379        }
380        break;
381      }
382      case OP_LOADNIL: {
383        if (a <= reg && reg <= b)
384          last = pc;  /* set registers from `a' to `b' */
385        break;
386      }
387      case OP_GETUPVAL:
388      case OP_SETUPVAL: {
389        check(b < pt->nups);
390        break;
391      }
392      case OP_GETGLOBAL:
393      case OP_SETGLOBAL: {
394        check(ttisstring(&pt->k[b]));
395        break;
396      }
397      case OP_SELF: {
398        checkreg(pt, a+1);
399        if (reg == a+1) last = pc;
400        break;
401      }
402      case OP_CONCAT: {
403        check(b < c);  /* at least two operands */
404        break;
405      }
406      case OP_TFORLOOP: {
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 */
410        break;
411      }
412      case OP_FORLOOP:
413      case OP_FORPREP:
414        checkreg(pt, a+3);
415        /* go through */
416      case OP_JMP: {
417        int dest = pc+1+b;
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 */
421        break;
422      }
423      case OP_CALL:
424      case OP_TAILCALL: {
425        if (b != 0) {
426          checkreg(pt, a+b-1);
427        }
428        c--;  /* c = num. returns */
429        if (c == LUA_MULTRET) {
430          check(checkopenop(pt, pc));
431        }
432        else if (c != 0)
433          checkreg(pt, a+c-1);
434        if (reg >= a) last = pc;  /* affect all registers above base */
435        break;
436      }
437      case OP_RETURN: {
438        b--;  /* b = num. returns */
439        if (b > 0) checkreg(pt, a+b-1);
440        break;
441      }
442      case OP_SETLIST: {
443        if (b > 0) checkreg(pt, a + b);
444        if (c == 0) {
445          pc++;
446          check(pc < pt->sizecode - 1);
447        }
448        break;
449      }
450      case OP_CLOSURE: {
451        int nup, j;
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);
458        }
459        if (reg != NO_REG)  /* tracing? */
460          pc += nup;  /* do not 'execute' these pseudo-instructions */
461        break;
462      }
463      case OP_VARARG: {
464        check((pt->is_vararg & VARARG_ISVARARG) &&
465             !(pt->is_vararg & VARARG_NEEDSARG));
466        b--;
467        if (b == LUA_MULTRET) check(checkopenop(pt, pc));
468        checkreg(pt, a+b-1);
469        break;
470      }
471      default: break;
472    }
473  }
474  return pt->code[last];
475}
476
477#undef check
478#undef checkjump
479#undef checkreg
480
481/* }====================================================== */
482
483
484int luaG_checkcode (const Proto *pt) {
485  return (symbexec(pt, pt->sizecode, NO_REG) != 0);
486}
487
488
489static const char *kname (Proto *p, int c) {
490  if (ISK(c) && ttisstring(&p->k[INDEXK(c)]))
491    return svalue(&p->k[INDEXK(c)]);
492  else
493    return "?";
494}
495
496
497static const char *getobjname (lua_State *L, CallInfo *ci, int stackpos,
498                               const char **name) {
499  if (isLua(ci)) {  /* a Lua function? */
500    Proto *p = ci_func(ci)->l.p;
501    int pc = currentpc(L, ci);
502    Instruction i;
503    *name = luaF_getlocalname(p, stackpos+1, pc);
504    if (*name)  /* is a local? */
505      return "local";
506    i = symbexec(p, pc, stackpos);  /* try symbolic execution */
507    lua_assert(pc != -1);
508    switch (GET_OPCODE(i)) {
509      case OP_GETGLOBAL: {
510        int g = GETARG_Bx(i);  /* global index */
511        lua_assert(ttisstring(&p->k[g]));
512        *name = svalue(&p->k[g]);
513        return "global";
514      }
515      case OP_MOVE: {
516        int a = GETARG_A(i);
517        int b = GETARG_B(i);  /* move from `b' to `a' */
518        if (b < a)
519          return getobjname(L, ci, b, name);  /* get name for `b' */
520        break;
521      }
522      case OP_GETTABLE: {
523        int k = GETARG_C(i);  /* key index */
524        *name = kname(p, k);
525        return "field";
526      }
527      case OP_GETUPVAL: {
528        int u = GETARG_B(i);  /* upvalue index */
529        *name = p->upvalues ? getstr(p->upvalues[u]) : "?";
530        return "upvalue";
531      }
532      case OP_SELF: {
533        int k = GETARG_C(i);  /* key index */
534        *name = kname(p, k);
535        return "method";
536      }
537      default: break;
538    }
539  }
540  return NULL;  /* no useful name found */
541}
542
543
544static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name) {
545  Instruction i;
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);
553  else
554    return NULL;  /* no useful name can be found */
555}
556
557
558/* only ANSI way to check whether a pointer points to an array */
559static int isinstack (CallInfo *ci, const TValue *o) {
560  StkId p;
561  for (p = ci->base; p < ci->top; p++)
562    if (o == p) return 1;
563  return 0;
564}
565
566
567void 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) :
572                         NULL;
573  if (kind)
574    luaG_runerror(L, "attempt to %s %s " LUA_QS " (a %s value)",
575                op, kind, name, t);
576  else
577    luaG_runerror(L, "attempt to %s a %s value", op, t);
578}
579
580
581void 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");
585}
586
587
588void luaG_aritherror (lua_State *L, const TValue *p1, const TValue *p2) {
589  TValue temp;
590  if (luaV_tonumber(p1, &temp) == NULL)
591    p2 = p1;  /* first operand is wrong */
592  luaG_typeerror(L, p2, "perform arithmetic on");
593}
594
595
596int 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)];
599  if (t1[2] == t2[2])
600    luaG_runerror(L, "attempt to compare two %s values", t1);
601  else
602    luaG_runerror(L, "attempt to compare %s with %s", t1, t2);
603  return 0;
604}
605
606
607static 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);
614  }
615}
616
617
618void 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 */
624    incr_top(L);
625    luaD_call(L, L->top - 2, 1);  /* call it */
626  }
627  luaD_throw(L, LUA_ERRRUN);
628}
629
630
631void luaG_runerror (lua_State *L, const char *fmt, ...) {
632  va_list argp;
633  va_start(argp, fmt);
634  addinfo(L, luaO_pushvfstring(L, fmt, argp));
635  va_end(argp);
636  luaG_errormsg(L);
637}
638