src/lib_debug.c

   1 /*
   2 ** Debug library.
   3 ** Copyright (C) 2005-2012 Mike Pall. See Copyright Notice in luajit.h
   4 **
   5 ** Major portions taken verbatim or adapted from the Lua interpreter.
   6 ** Copyright (C) 1994-2008 Lua.org, PUC-Rio. See Copyright Notice in lua.h
   7 */
   8
   9 #define lib_debug_c
  10 #define LUA_LIB
  11
  12 #include "lua.h"
  13 #include "lauxlib.h"
  14 #include "lualib.h"
  15
  16 #include "lj_obj.h"
  17 #include "lj_err.h"
  18 #include "lj_lib.h"
  19
  20 /* ------------------------------------------------------------------------ */
  21
  22 #define LJLIB_MODULE_debug
  23
  24 LJLIB_CF(debug_getregistry)
  25 {
  26   copyTV(L, L->top++, registry(L));
  27   return 1;
  28 }
  29
  30 LJLIB_CF(debug_getmetatable)
  31 {
  32   lj_lib_checkany(L, 1);
  33   if (!lua_getmetatable(L, 1)) {
  34     setnilV(L->top-1);
  35   }
  36   return 1;
  37 }
  38
  39 LJLIB_CF(debug_setmetatable)
  40 {
  41   lj_lib_checktabornil(L, 2);
  42   L->top = L->base+2;
  43   lua_setmetatable(L, 1);
  44 #if !LJ_52
  45   setboolV(L->top-1, 1);
  46 #endif
  47   return 1;
  48 }
  49
  50 LJLIB_CF(debug_getfenv)
  51 {
  52   lj_lib_checkany(L, 1);
  53   lua_getfenv(L, 1);
  54   return 1;
  55 }
  56
  57 LJLIB_CF(debug_setfenv)
  58 {
  59   lj_lib_checktab(L, 2);
  60   L->top = L->base+2;
  61   if (!lua_setfenv(L, 1))
  62     lj_err_caller(L, LJ_ERR_SETFENV);
  63   return 1;
  64 }
  65
  66 /* ------------------------------------------------------------------------ */
  67
  68 static void settabss(lua_State *L, const char *i, const char *v)
  69 {
  70   lua_pushstring(L, v);
  71   lua_setfield(L, -2, i);
  72 }
  73
  74 static void settabsi(lua_State *L, const char *i, int v)
  75 {
  76   lua_pushinteger(L, v);
  77   lua_setfield(L, -2, i);
  78 }
  79
  80 static lua_State *getthread(lua_State *L, int *arg)
  81 {
  82   if (L->base < L->top && tvisthread(L->base)) {
  83     *arg = 1;
  84     return threadV(L->base);
  85   } else {
  86     *arg = 0;
  87     return L;
  88   }
  89 }
  90
  91 static void treatstackoption(lua_State *L, lua_State *L1, const char *fname)
  92 {
  93   if (L == L1) {
  94     lua_pushvalue(L, -2);
  95     lua_remove(L, -3);
  96   }
  97   else
  98     lua_xmove(L1, L, 1);
  99   lua_setfield(L, -2, fname);
 100 }
 101
 102 LJLIB_CF(debug_getinfo)
 103 {
 104   lua_Debug ar;
 105   int arg, opt_f = 0, opt_L = 0;
 106   lua_State *L1 = getthread(L, &arg);
 107   const char *options = luaL_optstring(L, arg+2, "flnSu");
 108   if (lua_isnumber(L, arg+1)) {
 109     if (!lua_getstack(L1, (int)lua_tointeger(L, arg+1), &ar)) {
 110       setnilV(L->top-1);
 111       return 1;
 112     }
 113   } else if (L->base+arg < L->top && tvisfunc(L->base+arg)) {
 114     options = lua_pushfstring(L, ">%s", options);
 115     setfuncV(L1, L1->top++, funcV(L->base+arg));
 116   } else {
 117     lj_err_arg(L, arg+1, LJ_ERR_NOFUNCL);
 118   }
 119   if (!lua_getinfo(L1, options, &ar))
 120     lj_err_arg(L, arg+2, LJ_ERR_INVOPT);
 121   lua_createtable(L, 0, 16);  /* Create result table. */
 122   for (; *options; options++) {
 123     switch (*options) {
 124     case 'S':
 125       settabss(L, "source", ar.source);
 126       settabss(L, "short_src", ar.short_src);
 127       settabsi(L, "linedefined", ar.linedefined);
 128       settabsi(L, "lastlinedefined", ar.lastlinedefined);
 129       settabss(L, "what", ar.what);
 130       break;
 131     case 'l':
 132       settabsi(L, "currentline", ar.currentline);
 133       break;
 134     case 'u':
 135       settabsi(L, "nups", ar.nups);
 136       break;
 137     case 'n':
 138       settabss(L, "name", ar.name);
 139       settabss(L, "namewhat", ar.namewhat);
 140       break;
 141     case 'f': opt_f = 1; break;
 142     case 'L': opt_L = 1; break;
 143     default: break;
 144     }
 145   }
 146   if (opt_L) treatstackoption(L, L1, "activelines");
 147   if (opt_f) treatstackoption(L, L1, "func");
 148   return 1;  /* Return result table. */
 149 }
 150
 151 LJLIB_CF(debug_getlocal)
 152 {
 153   int arg;
 154   lua_State *L1 = getthread(L, &arg);
 155   lua_Debug ar;
 156   const char *name;
 157   int slot = lj_lib_checkint(L, arg+2);
 158   if (tvisfunc(L->base+arg)) {
 159     L->top = L->base+arg+1;
 160     lua_pushstring(L, lua_getlocal(L, NULL, slot));
 161     return 1;
 162   }
 163   if (!lua_getstack(L1, lj_lib_checkint(L, arg+1), &ar))
 164     lj_err_arg(L, arg+1, LJ_ERR_LVLRNG);
 165   name = lua_getlocal(L1, &ar, slot);
 166   if (name) {
 167     lua_xmove(L1, L, 1);
 168     lua_pushstring(L, name);
 169     lua_pushvalue(L, -2);
 170     return 2;
 171   } else {
 172     setnilV(L->top-1);
 173     return 1;
 174   }
 175 }
 176
 177 LJLIB_CF(debug_setlocal)
 178 {
 179   int arg;
 180   lua_State *L1 = getthread(L, &arg);
 181   lua_Debug ar;
 182   TValue *tv;
 183   if (!lua_getstack(L1, lj_lib_checkint(L, arg+1), &ar))
 184     lj_err_arg(L, arg+1, LJ_ERR_LVLRNG);
 185   tv = lj_lib_checkany(L, arg+3);
 186   copyTV(L1, L1->top++, tv);
 187   lua_pushstring(L, lua_setlocal(L1, &ar, lj_lib_checkint(L, arg+2)));
 188   return 1;
 189 }
 190
 191 static int debug_getupvalue(lua_State *L, int get)
 192 {
 193   int32_t n = lj_lib_checkint(L, 2);
 194   const char *name;
 195   lj_lib_checkfunc(L, 1);
 196   name = get ? lua_getupvalue(L, 1, n) : lua_setupvalue(L, 1, n);
 197   if (name) {
 198     lua_pushstring(L, name);
 199     if (!get) return 1;
 200     copyTV(L, L->top, L->top-2);
 201     L->top++;
 202     return 2;
 203   }
 204   return 0;
 205 }
 206
 207 LJLIB_CF(debug_getupvalue)
 208 {
 209   return debug_getupvalue(L, 1);
 210 }
 211
 212 LJLIB_CF(debug_setupvalue)
 213 {
 214   lj_lib_checkany(L, 3);
 215   return debug_getupvalue(L, 0);
 216 }
 217
 218 /* ------------------------------------------------------------------------ */
 219
 220 static const char KEY_HOOK = 'h';
 221
 222 static void hookf(lua_State *L, lua_Debug *ar)
 223 {
 224   static const char *const hooknames[] =
 225     {"call", "return", "line", "count", "tail return"};
 226   lua_pushlightuserdata(L, (void *)&KEY_HOOK);
 227   lua_rawget(L, LUA_REGISTRYINDEX);
 228   if (lua_isfunction(L, -1)) {
 229     lua_pushstring(L, hooknames[(int)ar->event]);
 230     if (ar->currentline >= 0)
 231       lua_pushinteger(L, ar->currentline);
 232     else lua_pushnil(L);
 233     lua_call(L, 2, 0);
 234   }
 235 }
 236
 237 static int makemask(const char *smask, int count)
 238 {
 239   int mask = 0;
 240   if (strchr(smask, 'c')) mask |= LUA_MASKCALL;
 241   if (strchr(smask, 'r')) mask |= LUA_MASKRET;
 242   if (strchr(smask, 'l')) mask |= LUA_MASKLINE;
 243   if (count > 0) mask |= LUA_MASKCOUNT;
 244   return mask;
 245 }
 246
 247 static char *unmakemask(int mask, char *smask)
 248 {
 249   int i = 0;
 250   if (mask & LUA_MASKCALL) smask[i++] = 'c';
 251   if (mask & LUA_MASKRET) smask[i++] = 'r';
 252   if (mask & LUA_MASKLINE) smask[i++] = 'l';
 253   smask[i] = '\0';
 254   return smask;
 255 }
 256
 257 LJLIB_CF(debug_sethook)
 258 {
 259   int arg, mask, count;
 260   lua_Hook func;
 261   (void)getthread(L, &arg);
 262   if (lua_isnoneornil(L, arg+1)) {
 263     lua_settop(L, arg+1);
 264     func = NULL; mask = 0; count = 0;  /* turn off hooks */
 265   } else {
 266     const char *smask = luaL_checkstring(L, arg+2);
 267     luaL_checktype(L, arg+1, LUA_TFUNCTION);
 268     count = luaL_optint(L, arg+3, 0);
 269     func = hookf; mask = makemask(smask, count);
 270   }
 271   lua_pushlightuserdata(L, (void *)&KEY_HOOK);
 272   lua_pushvalue(L, arg+1);
 273   lua_rawset(L, LUA_REGISTRYINDEX);
 274   lua_sethook(L, func, mask, count);
 275   return 0;
 276 }
 277
 278 LJLIB_CF(debug_gethook)
 279 {
 280   char buff[5];
 281   int mask = lua_gethookmask(L);
 282   lua_Hook hook = lua_gethook(L);
 283   if (hook != NULL && hook != hookf) {  /* external hook? */
 284     lua_pushliteral(L, "external hook");
 285   } else {
 286     lua_pushlightuserdata(L, (void *)&KEY_HOOK);
 287     lua_rawget(L, LUA_REGISTRYINDEX);   /* get hook */
 288   }
 289   lua_pushstring(L, unmakemask(mask, buff));
 290   lua_pushinteger(L, lua_gethookcount(L));
 291   return 3;
 292 }
 293
 294 /* ------------------------------------------------------------------------ */
 295
 296 LJLIB_CF(debug_debug)
 297 {
 298   for (;;) {
 299     char buffer[250];
 300     fputs("lua_debug> ", stderr);
 301     if (fgets(buffer, sizeof(buffer), stdin) == 0 ||
 302         strcmp(buffer, "cont\n") == 0)
 303       return 0;
 304     if (luaL_loadbuffer(L, buffer, strlen(buffer), "=(debug command)") ||
 305         lua_pcall(L, 0, 0, 0)) {
 306       fputs(lua_tostring(L, -1), stderr);
 307       fputs("\n", stderr);
 308     }
 309     lua_settop(L, 0);  /* remove eventual returns */
 310   }
 311 }
 312
 313 /* ------------------------------------------------------------------------ */
 314
 315 #define LEVELS1 12      /* size of the first part of the stack */
 316 #define LEVELS2 10      /* size of the second part of the stack */
 317
 318 LJLIB_CF(debug_traceback)
 319 {
 320   int level;
 321   int firstpart = 1;  /* still before eventual `...' */
 322   int arg;
 323   lua_State *L1 = getthread(L, &arg);
 324   lua_Debug ar;
 325   if (lua_isnumber(L, arg+2)) {
 326     level = (int)lua_tointeger(L, arg+2);
 327     lua_pop(L, 1);
 328   }
 329   else
 330     level = (L == L1) ? 1 : 0;  /* level 0 may be this own function */
 331   if (lua_gettop(L) == arg)
 332     lua_pushliteral(L, "");
 333   else if (!lua_isstring(L, arg+1)) return 1;  /* message is not a string */
 334   else lua_pushliteral(L, "\n");
 335   lua_pushliteral(L, "stack traceback:");
 336   while (lua_getstack(L1, level++, &ar)) {
 337     if (level > LEVELS1 && firstpart) {
 338       /* no more than `LEVELS2' more levels? */
 339       if (!lua_getstack(L1, level+LEVELS2, &ar)) {
 340         level--;  /* keep going */
 341       } else {
 342         lua_pushliteral(L, "\n\t...");  /* too many levels */
 343         /* This only works with LuaJIT 2.x. Avoids O(n^2) behaviour. */
 344         lua_getstack(L1, -10, &ar);
 345         level = ar.i_ci - LEVELS2;
 346       }
 347       firstpart = 0;
 348       continue;
 349     }
 350     lua_pushliteral(L, "\n\t");
 351     lua_getinfo(L1, "Snl", &ar);
 352     lua_pushfstring(L, "%s:", ar.short_src);
 353     if (ar.currentline > 0)
 354       lua_pushfstring(L, "%d:", ar.currentline);
 355     if (*ar.namewhat != '\0') {  /* is there a name? */
 356       lua_pushfstring(L, " in function " LUA_QS, ar.name);
 357     } else {
 358       if (*ar.what == 'm')  /* main? */
 359         lua_pushfstring(L, " in main chunk");
 360       else if (*ar.what == 'C' || *ar.what == 't')
 361         lua_pushliteral(L, " ?");  /* C function or tail call */
 362       else
 363         lua_pushfstring(L, " in function <%s:%d>",
 364                         ar.short_src, ar.linedefined);
 365     }
 366     lua_concat(L, lua_gettop(L) - arg);
 367   }
 368   lua_concat(L, lua_gettop(L) - arg);
 369   return 1;
 370 }
 371
 372 /* ------------------------------------------------------------------------ */
 373
 374 #include "lj_libdef.h"
 375
 376 LUALIB_API int luaopen_debug(lua_State *L)
 377 {
 378   LJ_LIB_REG(L, LUA_DBLIBNAME, debug);
 379   return 1;
 380 }
 381