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