external/mit/lua/dist/src/ldblib.c

   1 /*      $NetBSD: ldblib.c,v 1.1.1.2 2012/03/15 00:08:10 alnsn Exp $     */
   2
   3 /*
   4 ** $Id: ldblib.c,v 1.1.1.2 2012/03/15 00:08:10 alnsn Exp $
   5 ** Interface from Lua to its debug API
   6 ** See Copyright Notice in lua.h
   7 */
   8
   9
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13
  14 #define ldblib_c
  15 #define LUA_LIB
  16
  17 #include "lua.h"
  18
  19 #include "lauxlib.h"
  20 #include "lualib.h"
  21
  22
  23
  24 static int db_getregistry (lua_State *L) {
  25   lua_pushvalue(L, LUA_REGISTRYINDEX);
  26   return 1;
  27 }
  28
  29
  30 static int db_getmetatable (lua_State *L) {
  31   luaL_checkany(L, 1);
  32   if (!lua_getmetatable(L, 1)) {
  33     lua_pushnil(L);  /* no metatable */
  34   }
  35   return 1;
  36 }
  37
  38
  39 static int db_setmetatable (lua_State *L) {
  40   int t = lua_type(L, 2);
  41   luaL_argcheck(L, t == LUA_TNIL || t == LUA_TTABLE, 2,
  42                     "nil or table expected");
  43   lua_settop(L, 2);
  44   lua_pushboolean(L, lua_setmetatable(L, 1));
  45   return 1;
  46 }
  47
  48
  49 static int db_getfenv (lua_State *L) {
  50   luaL_checkany(L, 1);
  51   lua_getfenv(L, 1);
  52   return 1;
  53 }
  54
  55
  56 static int db_setfenv (lua_State *L) {
  57   luaL_checktype(L, 2, LUA_TTABLE);
  58   lua_settop(L, 2);
  59   if (lua_setfenv(L, 1) == 0)
  60     luaL_error(L, LUA_QL("setfenv")
  61                   " cannot change environment of given object");
  62   return 1;
  63 }
  64
  65
  66 static void settabss (lua_State *L, const char *i, const char *v) {
  67   lua_pushstring(L, v);
  68   lua_setfield(L, -2, i);
  69 }
  70
  71
  72 static void settabsi (lua_State *L, const char *i, int v) {
  73   lua_pushinteger(L, v);
  74   lua_setfield(L, -2, i);
  75 }
  76
  77
  78 static lua_State *getthread (lua_State *L, int *arg) {
  79   if (lua_isthread(L, 1)) {
  80     *arg = 1;
  81     return lua_tothread(L, 1);
  82   }
  83   else {
  84     *arg = 0;
  85     return L;
  86   }
  87 }
  88
  89
  90 static void treatstackoption (lua_State *L, lua_State *L1, const char *fname) {
  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
 101 static int db_getinfo (lua_State *L) {
 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       lua_pushnil(L);  /* level out of range */
 109       return 1;
 110     }
 111   }
 112   else if (lua_isfunction(L, arg+1)) {
 113     lua_pushfstring(L, ">%s", options);
 114     options = lua_tostring(L, -1);
 115     lua_pushvalue(L, arg+1);
 116     lua_xmove(L, L1, 1);
 117   }
 118   else
 119     return luaL_argerror(L, arg+1, "function or level expected");
 120   if (!lua_getinfo(L1, options, &ar))
 121     return luaL_argerror(L, arg+2, "invalid option");
 122   lua_createtable(L, 0, 2);
 123   if (strchr(options, 'S')) {
 124     settabss(L, "source", ar.source);
 125     settabss(L, "short_src", ar.short_src);
 126     settabsi(L, "linedefined", ar.linedefined);
 127     settabsi(L, "lastlinedefined", ar.lastlinedefined);
 128     settabss(L, "what", ar.what);
 129   }
 130   if (strchr(options, 'l'))
 131     settabsi(L, "currentline", ar.currentline);
 132   if (strchr(options, 'u'))
 133     settabsi(L, "nups", ar.nups);
 134   if (strchr(options, 'n')) {
 135     settabss(L, "name", ar.name);
 136     settabss(L, "namewhat", ar.namewhat);
 137   }
 138   if (strchr(options, 'L'))
 139     treatstackoption(L, L1, "activelines");
 140   if (strchr(options, 'f'))
 141     treatstackoption(L, L1, "func");
 142   return 1;  /* return table */
 143 }
 144
 145
 146 static int db_getlocal (lua_State *L) {
 147   int arg;
 148   lua_State *L1 = getthread(L, &arg);
 149   lua_Debug ar;
 150   const char *name;
 151   if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar))  /* out of range? */
 152     return luaL_argerror(L, arg+1, "level out of range");
 153   name = lua_getlocal(L1, &ar, luaL_checkint(L, arg+2));
 154   if (name) {
 155     lua_xmove(L1, L, 1);
 156     lua_pushstring(L, name);
 157     lua_pushvalue(L, -2);
 158     return 2;
 159   }
 160   else {
 161     lua_pushnil(L);
 162     return 1;
 163   }
 164 }
 165
 166
 167 static int db_setlocal (lua_State *L) {
 168   int arg;
 169   lua_State *L1 = getthread(L, &arg);
 170   lua_Debug ar;
 171   if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar))  /* out of range? */
 172     return luaL_argerror(L, arg+1, "level out of range");
 173   luaL_checkany(L, arg+3);
 174   lua_settop(L, arg+3);
 175   lua_xmove(L, L1, 1);
 176   lua_pushstring(L, lua_setlocal(L1, &ar, luaL_checkint(L, arg+2)));
 177   return 1;
 178 }
 179
 180
 181 static int auxupvalue (lua_State *L, int get) {
 182   const char *name;
 183   int n = luaL_checkint(L, 2);
 184   luaL_checktype(L, 1, LUA_TFUNCTION);
 185   if (lua_iscfunction(L, 1)) return 0;  /* cannot touch C upvalues from Lua */
 186   name = get ? lua_getupvalue(L, 1, n) : lua_setupvalue(L, 1, n);
 187   if (name == NULL) return 0;
 188   lua_pushstring(L, name);
 189   lua_insert(L, -(get+1));
 190   return get + 1;
 191 }
 192
 193
 194 static int db_getupvalue (lua_State *L) {
 195   return auxupvalue(L, 1);
 196 }
 197
 198
 199 static int db_setupvalue (lua_State *L) {
 200   luaL_checkany(L, 3);
 201   return auxupvalue(L, 0);
 202 }
 203
 204
 205
 206 static const char KEY_HOOK = 'h';
 207
 208
 209 static void hookf (lua_State *L, lua_Debug *ar) {
 210   static const char *const hooknames[] =
 211     {"call", "return", "line", "count", "tail return"};
 212   lua_pushlightuserdata(L, (void *)&KEY_HOOK);
 213   lua_rawget(L, LUA_REGISTRYINDEX);
 214   lua_pushlightuserdata(L, L);
 215   lua_rawget(L, -2);
 216   if (lua_isfunction(L, -1)) {
 217     lua_pushstring(L, hooknames[(int)ar->event]);
 218     if (ar->currentline >= 0)
 219       lua_pushinteger(L, ar->currentline);
 220     else lua_pushnil(L);
 221     lua_assert(lua_getinfo(L, "lS", ar));
 222     lua_call(L, 2, 0);
 223   }
 224 }
 225
 226
 227 static int makemask (const char *smask, int count) {
 228   int mask = 0;
 229   if (strchr(smask, 'c')) mask |= LUA_MASKCALL;
 230   if (strchr(smask, 'r')) mask |= LUA_MASKRET;
 231   if (strchr(smask, 'l')) mask |= LUA_MASKLINE;
 232   if (count > 0) mask |= LUA_MASKCOUNT;
 233   return mask;
 234 }
 235
 236
 237 static char *unmakemask (int mask, char *smask) {
 238   int i = 0;
 239   if (mask & LUA_MASKCALL) smask[i++] = 'c';
 240   if (mask & LUA_MASKRET) smask[i++] = 'r';
 241   if (mask & LUA_MASKLINE) smask[i++] = 'l';
 242   smask[i] = '\0';
 243   return smask;
 244 }
 245
 246
 247 static void gethooktable (lua_State *L) {
 248   lua_pushlightuserdata(L, (void *)&KEY_HOOK);
 249   lua_rawget(L, LUA_REGISTRYINDEX);
 250   if (!lua_istable(L, -1)) {
 251     lua_pop(L, 1);
 252     lua_createtable(L, 0, 1);
 253     lua_pushlightuserdata(L, (void *)&KEY_HOOK);
 254     lua_pushvalue(L, -2);
 255     lua_rawset(L, LUA_REGISTRYINDEX);
 256   }
 257 }
 258
 259
 260 static int db_sethook (lua_State *L) {
 261   int arg, mask, count;
 262   lua_Hook func;
 263   lua_State *L1 = getthread(L, &arg);
 264   if (lua_isnoneornil(L, arg+1)) {
 265     lua_settop(L, arg+1);
 266     func = NULL; mask = 0; count = 0;  /* turn off hooks */
 267   }
 268   else {
 269     const char *smask = luaL_checkstring(L, arg+2);
 270     luaL_checktype(L, arg+1, LUA_TFUNCTION);
 271     count = luaL_optint(L, arg+3, 0);
 272     func = hookf; mask = makemask(smask, count);
 273   }
 274   gethooktable(L);
 275   lua_pushlightuserdata(L, L1);
 276   lua_pushvalue(L, arg+1);
 277   lua_rawset(L, -3);  /* set new hook */
 278   lua_pop(L, 1);  /* remove hook table */
 279   lua_sethook(L1, func, mask, count);  /* set hooks */
 280   return 0;
 281 }
 282
 283
 284 static int db_gethook (lua_State *L) {
 285   int arg;
 286   lua_State *L1 = getthread(L, &arg);
 287   char buff[5];
 288   int mask = lua_gethookmask(L1);
 289   lua_Hook hook = lua_gethook(L1);
 290   if (hook != NULL && hook != hookf)  /* external hook? */
 291     lua_pushliteral(L, "external hook");
 292   else {
 293     gethooktable(L);
 294     lua_pushlightuserdata(L, L1);
 295     lua_rawget(L, -2);   /* get hook */
 296     lua_remove(L, -2);  /* remove hook table */
 297   }
 298   lua_pushstring(L, unmakemask(mask, buff));
 299   lua_pushinteger(L, lua_gethookcount(L1));
 300   return 3;
 301 }
 302
 303
 304 static int db_debug (lua_State *L) {
 305   for (;;) {
 306     char buffer[250];
 307     fputs("lua_debug> ", stderr);
 308     if (fgets(buffer, sizeof(buffer), stdin) == 0 ||
 309         strcmp(buffer, "cont\n") == 0)
 310       return 0;
 311     if (luaL_loadbuffer(L, buffer, strlen(buffer), "=(debug command)") ||
 312         lua_pcall(L, 0, 0, 0)) {
 313       fputs(lua_tostring(L, -1), stderr);
 314       fputs("\n", stderr);
 315     }
 316     lua_settop(L, 0);  /* remove eventual returns */
 317   }
 318 }
 319
 320
 321 #define LEVELS1 12      /* size of the first part of the stack */
 322 #define LEVELS2 10      /* size of the second part of the stack */
 323
 324 static int db_errorfb (lua_State *L) {
 325   int level;
 326   int firstpart = 1;  /* still before eventual `...' */
 327   int arg;
 328   lua_State *L1 = getthread(L, &arg);
 329   lua_Debug ar;
 330   if (lua_isnumber(L, arg+2)) {
 331     level = (int)lua_tointeger(L, arg+2);
 332     lua_pop(L, 1);
 333   }
 334   else
 335     level = (L == L1) ? 1 : 0;  /* level 0 may be this own function */
 336   if (lua_gettop(L) == arg)
 337     lua_pushliteral(L, "");
 338   else if (!lua_isstring(L, arg+1)) return 1;  /* message is not a string */
 339   else lua_pushliteral(L, "\n");
 340   lua_pushliteral(L, "stack traceback:");
 341   while (lua_getstack(L1, level++, &ar)) {
 342     if (level > LEVELS1 && firstpart) {
 343       /* no more than `LEVELS2' more levels? */
 344       if (!lua_getstack(L1, level+LEVELS2, &ar))
 345         level--;  /* keep going */
 346       else {
 347         lua_pushliteral(L, "\n\t...");  /* too many levels */
 348         while (lua_getstack(L1, level+LEVELS2, &ar))  /* find last levels */
 349           level++;
 350       }
 351       firstpart = 0;
 352       continue;
 353     }
 354     lua_pushliteral(L, "\n\t");
 355     lua_getinfo(L1, "Snl", &ar);
 356     lua_pushfstring(L, "%s:", ar.short_src);
 357     if (ar.currentline > 0)
 358       lua_pushfstring(L, "%d:", ar.currentline);
 359     if (*ar.namewhat != '\0')  /* is there a name? */
 360         lua_pushfstring(L, " in function " LUA_QS, ar.name);
 361     else {
 362       if (*ar.what == 'm')  /* main? */
 363         lua_pushfstring(L, " in main chunk");
 364       else if (*ar.what == 'C' || *ar.what == 't')
 365         lua_pushliteral(L, " ?");  /* C function or tail call */
 366       else
 367         lua_pushfstring(L, " in function <%s:%d>",
 368                            ar.short_src, ar.linedefined);
 369     }
 370     lua_concat(L, lua_gettop(L) - arg);
 371   }
 372   lua_concat(L, lua_gettop(L) - arg);
 373   return 1;
 374 }
 375
 376
 377 static const luaL_Reg dblib[] = {
 378   {"debug", db_debug},
 379   {"getfenv", db_getfenv},
 380   {"gethook", db_gethook},
 381   {"getinfo", db_getinfo},
 382   {"getlocal", db_getlocal},
 383   {"getregistry", db_getregistry},
 384   {"getmetatable", db_getmetatable},
 385   {"getupvalue", db_getupvalue},
 386   {"setfenv", db_setfenv},
 387   {"sethook", db_sethook},
 388   {"setlocal", db_setlocal},
 389   {"setmetatable", db_setmetatable},
 390   {"setupvalue", db_setupvalue},
 391   {"traceback", db_errorfb},
 392   {NULL, NULL}
 393 };
 394
 395
 396 LUALIB_API int luaopen_debug (lua_State *L) {
 397   luaL_register(L, LUA_DBLIBNAME, dblib);
 398   return 1;
 399 }
 400