source/libs/lua52/lua52-src/src/ldblib.c

   1 /*
   2 ** $Id: ldblib.c,v 1.132.1.2 2015/02/19 17:16:55 roberto Exp $
   3 ** Interface from Lua to its debug API
   4 ** See Copyright Notice in lua.h
   5 */
   6
   7
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <string.h>
  11
  12 #define ldblib_c
  13 #define LUA_LIB
  14
  15 #include "lua.h"
  16
  17 #include "lauxlib.h"
  18 #include "lualib.h"
  19
  20
  21 #define HOOKKEY         "_HKEY"
  22
  23
  24 static void checkstack (lua_State *L, lua_State *L1, int n) {
  25   if (L != L1 && !lua_checkstack(L1, n))
  26     luaL_error(L, "stack overflow");
  27 }
  28
  29
  30 static int db_getregistry (lua_State *L) {
  31   lua_pushvalue(L, LUA_REGISTRYINDEX);
  32   return 1;
  33 }
  34
  35
  36 static int db_getmetatable (lua_State *L) {
  37   luaL_checkany(L, 1);
  38   if (!lua_getmetatable(L, 1)) {
  39     lua_pushnil(L);  /* no metatable */
  40   }
  41   return 1;
  42 }
  43
  44
  45 static int db_setmetatable (lua_State *L) {
  46   int t = lua_type(L, 2);
  47   luaL_argcheck(L, t == LUA_TNIL || t == LUA_TTABLE, 2,
  48                     "nil or table expected");
  49   lua_settop(L, 2);
  50   lua_setmetatable(L, 1);
  51   return 1;  /* return 1st argument */
  52 }
  53
  54
  55 static int db_getuservalue (lua_State *L) {
  56   if (lua_type(L, 1) != LUA_TUSERDATA)
  57     lua_pushnil(L);
  58   else
  59     lua_getuservalue(L, 1);
  60   return 1;
  61 }
  62
  63
  64 static int db_setuservalue (lua_State *L) {
  65   if (lua_type(L, 1) == LUA_TLIGHTUSERDATA)
  66     luaL_argerror(L, 1, "full userdata expected, got light userdata");
  67   luaL_checktype(L, 1, LUA_TUSERDATA);
  68   if (!lua_isnoneornil(L, 2))
  69     luaL_checktype(L, 2, LUA_TTABLE);
  70   lua_settop(L, 2);
  71   lua_setuservalue(L, 1);
  72   return 1;
  73 }
  74
  75
  76 static void settabss (lua_State *L, const char *i, const char *v) {
  77   lua_pushstring(L, v);
  78   lua_setfield(L, -2, i);
  79 }
  80
  81
  82 static void settabsi (lua_State *L, const char *i, int v) {
  83   lua_pushinteger(L, v);
  84   lua_setfield(L, -2, i);
  85 }
  86
  87
  88 static void settabsb (lua_State *L, const char *i, int v) {
  89   lua_pushboolean(L, v);
  90   lua_setfield(L, -2, i);
  91 }
  92
  93
  94 static lua_State *getthread (lua_State *L, int *arg) {
  95   if (lua_isthread(L, 1)) {
  96     *arg = 1;
  97     return lua_tothread(L, 1);
  98   }
  99   else {
 100     *arg = 0;
 101     return L;
 102   }
 103 }
 104
 105
 106 static void treatstackoption (lua_State *L, lua_State *L1, const char *fname) {
 107   if (L == L1) {
 108     lua_pushvalue(L, -2);
 109     lua_remove(L, -3);
 110   }
 111   else
 112     lua_xmove(L1, L, 1);
 113   lua_setfield(L, -2, fname);
 114 }
 115
 116
 117 static int db_getinfo (lua_State *L) {
 118   lua_Debug ar;
 119   int arg;
 120   lua_State *L1 = getthread(L, &arg);
 121   const char *options = luaL_optstring(L, arg+2, "flnStu");
 122   checkstack(L, L1, 3);
 123   if (lua_isnumber(L, arg+1)) {
 124     if (!lua_getstack(L1, (int)lua_tointeger(L, arg+1), &ar)) {
 125       lua_pushnil(L);  /* level out of range */
 126       return 1;
 127     }
 128   }
 129   else if (lua_isfunction(L, arg+1)) {
 130     lua_pushfstring(L, ">%s", options);
 131     options = lua_tostring(L, -1);
 132     lua_pushvalue(L, arg+1);
 133     lua_xmove(L, L1, 1);
 134   }
 135   else
 136     return luaL_argerror(L, arg+1, "function or level expected");
 137   if (!lua_getinfo(L1, options, &ar))
 138     return luaL_argerror(L, arg+2, "invalid option");
 139   lua_createtable(L, 0, 2);
 140   if (strchr(options, 'S')) {
 141     settabss(L, "source", ar.source);
 142     settabss(L, "short_src", ar.short_src);
 143     settabsi(L, "linedefined", ar.linedefined);
 144     settabsi(L, "lastlinedefined", ar.lastlinedefined);
 145     settabss(L, "what", ar.what);
 146   }
 147   if (strchr(options, 'l'))
 148     settabsi(L, "currentline", ar.currentline);
 149   if (strchr(options, 'u')) {
 150     settabsi(L, "nups", ar.nups);
 151     settabsi(L, "nparams", ar.nparams);
 152     settabsb(L, "isvararg", ar.isvararg);
 153   }
 154   if (strchr(options, 'n')) {
 155     settabss(L, "name", ar.name);
 156     settabss(L, "namewhat", ar.namewhat);
 157   }
 158   if (strchr(options, 't'))
 159     settabsb(L, "istailcall", ar.istailcall);
 160   if (strchr(options, 'L'))
 161     treatstackoption(L, L1, "activelines");
 162   if (strchr(options, 'f'))
 163     treatstackoption(L, L1, "func");
 164   return 1;  /* return table */
 165 }
 166
 167
 168 static int db_getlocal (lua_State *L) {
 169   int arg;
 170   lua_State *L1 = getthread(L, &arg);
 171   lua_Debug ar;
 172   const char *name;
 173   int nvar = luaL_checkint(L, arg+2);  /* local-variable index */
 174   if (lua_isfunction(L, arg + 1)) {  /* function argument? */
 175     lua_pushvalue(L, arg + 1);  /* push function */
 176     lua_pushstring(L, lua_getlocal(L, NULL, nvar));  /* push local name */
 177     return 1;
 178   }
 179   else {  /* stack-level argument */
 180     if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar))  /* out of range? */
 181       return luaL_argerror(L, arg+1, "level out of range");
 182     checkstack(L, L1, 1);
 183     name = lua_getlocal(L1, &ar, nvar);
 184     if (name) {
 185       lua_xmove(L1, L, 1);  /* push local value */
 186       lua_pushstring(L, name);  /* push name */
 187       lua_pushvalue(L, -2);  /* re-order */
 188       return 2;
 189     }
 190     else {
 191       lua_pushnil(L);  /* no name (nor value) */
 192       return 1;
 193     }
 194   }
 195 }
 196
 197
 198 static int db_setlocal (lua_State *L) {
 199   int arg;
 200   lua_State *L1 = getthread(L, &arg);
 201   lua_Debug ar;
 202   if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar))  /* out of range? */
 203     return luaL_argerror(L, arg+1, "level out of range");
 204   luaL_checkany(L, arg+3);
 205   lua_settop(L, arg+3);
 206   checkstack(L, L1, 1);
 207   lua_xmove(L, L1, 1);
 208   lua_pushstring(L, lua_setlocal(L1, &ar, luaL_checkint(L, arg+2)));
 209   return 1;
 210 }
 211
 212
 213 static int auxupvalue (lua_State *L, int get) {
 214   const char *name;
 215   int n = luaL_checkint(L, 2);
 216   luaL_checktype(L, 1, LUA_TFUNCTION);
 217   name = get ? lua_getupvalue(L, 1, n) : lua_setupvalue(L, 1, n);
 218   if (name == NULL) return 0;
 219   lua_pushstring(L, name);
 220   lua_insert(L, -(get+1));
 221   return get + 1;
 222 }
 223
 224
 225 static int db_getupvalue (lua_State *L) {
 226   return auxupvalue(L, 1);
 227 }
 228
 229
 230 static int db_setupvalue (lua_State *L) {
 231   luaL_checkany(L, 3);
 232   return auxupvalue(L, 0);
 233 }
 234
 235
 236 static int checkupval (lua_State *L, int argf, int argnup) {
 237   lua_Debug ar;
 238   int nup = luaL_checkint(L, argnup);
 239   luaL_checktype(L, argf, LUA_TFUNCTION);
 240   lua_pushvalue(L, argf);
 241   lua_getinfo(L, ">u", &ar);
 242   luaL_argcheck(L, 1 <= nup && nup <= ar.nups, argnup, "invalid upvalue index");
 243   return nup;
 244 }
 245
 246
 247 static int db_upvalueid (lua_State *L) {
 248   int n = checkupval(L, 1, 2);
 249   lua_pushlightuserdata(L, lua_upvalueid(L, 1, n));
 250   return 1;
 251 }
 252
 253
 254 static int db_upvaluejoin (lua_State *L) {
 255   int n1 = checkupval(L, 1, 2);
 256   int n2 = checkupval(L, 3, 4);
 257   luaL_argcheck(L, !lua_iscfunction(L, 1), 1, "Lua function expected");
 258   luaL_argcheck(L, !lua_iscfunction(L, 3), 3, "Lua function expected");
 259   lua_upvaluejoin(L, 1, n1, 3, n2);
 260   return 0;
 261 }
 262
 263
 264 #define gethooktable(L) luaL_getsubtable(L, LUA_REGISTRYINDEX, HOOKKEY)
 265
 266
 267 static void hookf (lua_State *L, lua_Debug *ar) {
 268   static const char *const hooknames[] =
 269     {"call", "return", "line", "count", "tail call"};
 270   gethooktable(L);
 271   lua_pushthread(L);
 272   lua_rawget(L, -2);
 273   if (lua_isfunction(L, -1)) {
 274     lua_pushstring(L, hooknames[(int)ar->event]);
 275     if (ar->currentline >= 0)
 276       lua_pushinteger(L, ar->currentline);
 277     else lua_pushnil(L);
 278     lua_assert(lua_getinfo(L, "lS", ar));
 279     lua_call(L, 2, 0);
 280   }
 281 }
 282
 283
 284 static int makemask (const char *smask, int count) {
 285   int mask = 0;
 286   if (strchr(smask, 'c')) mask |= LUA_MASKCALL;
 287   if (strchr(smask, 'r')) mask |= LUA_MASKRET;
 288   if (strchr(smask, 'l')) mask |= LUA_MASKLINE;
 289   if (count > 0) mask |= LUA_MASKCOUNT;
 290   return mask;
 291 }
 292
 293
 294 static char *unmakemask (int mask, char *smask) {
 295   int i = 0;
 296   if (mask & LUA_MASKCALL) smask[i++] = 'c';
 297   if (mask & LUA_MASKRET) smask[i++] = 'r';
 298   if (mask & LUA_MASKLINE) smask[i++] = 'l';
 299   smask[i] = '\0';
 300   return smask;
 301 }
 302
 303
 304 static int db_sethook (lua_State *L) {
 305   int arg, mask, count;
 306   lua_Hook func;
 307   lua_State *L1 = getthread(L, &arg);
 308   if (lua_isnoneornil(L, arg+1)) {
 309     lua_settop(L, arg+1);
 310     func = NULL; mask = 0; count = 0;  /* turn off hooks */
 311   }
 312   else {
 313     const char *smask = luaL_checkstring(L, arg+2);
 314     luaL_checktype(L, arg+1, LUA_TFUNCTION);
 315     count = luaL_optint(L, arg+3, 0);
 316     func = hookf; mask = makemask(smask, count);
 317   }
 318   if (gethooktable(L) == 0) {  /* creating hook table? */
 319     lua_pushstring(L, "k");
 320     lua_setfield(L, -2, "__mode");  /** hooktable.__mode = "k" */
 321     lua_pushvalue(L, -1);
 322     lua_setmetatable(L, -2);  /* setmetatable(hooktable) = hooktable */
 323   }
 324   checkstack(L, L1, 1);
 325   lua_pushthread(L1); lua_xmove(L1, L, 1);
 326   lua_pushvalue(L, arg+1);
 327   lua_rawset(L, -3);  /* set new hook */
 328   lua_sethook(L1, func, mask, count);  /* set hooks */
 329   return 0;
 330 }
 331
 332
 333 static int db_gethook (lua_State *L) {
 334   int arg;
 335   lua_State *L1 = getthread(L, &arg);
 336   char buff[5];
 337   int mask = lua_gethookmask(L1);
 338   lua_Hook hook = lua_gethook(L1);
 339   if (hook != NULL && hook != hookf)  /* external hook? */
 340     lua_pushliteral(L, "external hook");
 341   else {
 342     gethooktable(L);
 343     checkstack(L, L1, 1);
 344     lua_pushthread(L1); lua_xmove(L1, L, 1);
 345     lua_rawget(L, -2);   /* get hook */
 346     lua_remove(L, -2);  /* remove hook table */
 347   }
 348   lua_pushstring(L, unmakemask(mask, buff));
 349   lua_pushinteger(L, lua_gethookcount(L1));
 350   return 3;
 351 }
 352
 353
 354 static int db_debug (lua_State *L) {
 355   for (;;) {
 356     char buffer[250];
 357     luai_writestringerror("%s", "lua_debug> ");
 358     if (fgets(buffer, sizeof(buffer), stdin) == 0 ||
 359         strcmp(buffer, "cont\n") == 0)
 360       return 0;
 361     if (luaL_loadbuffer(L, buffer, strlen(buffer), "=(debug command)") ||
 362         lua_pcall(L, 0, 0, 0))
 363       luai_writestringerror("%s\n", lua_tostring(L, -1));
 364     lua_settop(L, 0);  /* remove eventual returns */
 365   }
 366 }
 367
 368
 369 static int db_traceback (lua_State *L) {
 370   int arg;
 371   lua_State *L1 = getthread(L, &arg);
 372   const char *msg = lua_tostring(L, arg + 1);
 373   if (msg == NULL && !lua_isnoneornil(L, arg + 1))  /* non-string 'msg'? */
 374     lua_pushvalue(L, arg + 1);  /* return it untouched */
 375   else {
 376     int level = luaL_optint(L, arg + 2, (L == L1) ? 1 : 0);
 377     luaL_traceback(L, L1, msg, level);
 378   }
 379   return 1;
 380 }
 381
 382
 383 static const luaL_Reg dblib[] = {
 384   {"debug", db_debug},
 385   {"getuservalue", db_getuservalue},
 386   {"gethook", db_gethook},
 387   {"getinfo", db_getinfo},
 388   {"getlocal", db_getlocal},
 389   {"getregistry", db_getregistry},
 390   {"getmetatable", db_getmetatable},
 391   {"getupvalue", db_getupvalue},
 392   {"upvaluejoin", db_upvaluejoin},
 393   {"upvalueid", db_upvalueid},
 394   {"setuservalue", db_setuservalue},
 395   {"sethook", db_sethook},
 396   {"setlocal", db_setlocal},
 397   {"setmetatable", db_setmetatable},
 398   {"setupvalue", db_setupvalue},
 399   {"traceback", db_traceback},
 400   {NULL, NULL}
 401 };
 402
 403
 404 LUAMOD_API int luaopen_debug (lua_State *L) {
 405   luaL_newlib(L, dblib);
 406   return 1;
 407 }
 408