/*

 ** $Id: lbaselib.c,v 1.191.1.6 2008/02/14 16:46:22 roberto Exp $

 ** Basic library

 ** See Copyright Notice in lua.h

 */

 

 

 

 #include <ctype.h>

 #include <stdio.h>

 #include <stdlib.h>

 #include <string.h>

 

 #define lbaselib_c

 #define LUA_LIB

 

 #include "lua.h"

 

 #include "lauxlib.h"

 #include "lualib.h"

 

 

 

 

 /*

 ** If your system does not support `stdout', you can just remove this function.

 ** If you need, you can define your own `print' function, following this

 ** model but changing `fputs' to put the strings at a proper place

 ** (a console window or a log file, for instance).

 */

 static int luaB_print (lua_State *L) {

   int n = lua_gettop(L);  /* number of arguments */

   int i;

   lua_getglobal(L, "tostring");

   for (i=1; i<=n; i++) {

     const char *s;

     lua_pushvalue(L, -1);  /* function to be called */

     lua_pushvalue(L, i);   /* value to print */

     lua_call(L, 1, 1);

     s = lua_tostring(L, -1);  /* get result */

     if (s == NULL)

       return luaL_error(L, LUA_QL("tostring") " must return a string to "

                            LUA_QL("print"));

     if (i>1) fputs("\t", stdout);

     fputs(s, stdout);

     lua_pop(L, 1);  /* pop result */

   }

   fputs("\n", stdout);

   return 0;

 }

 

 

 static int luaB_tonumber (lua_State *L) {

   int base = luaL_optint(L, 2, 10);

   if (base == 10) {  /* standard conversion */

     luaL_checkany(L, 1);

     if (lua_isnumber(L, 1)) {

       lua_pushnumber(L, lua_tonumber(L, 1));

       return 1;

     }

   }

   else {

     const char *s1 = luaL_checkstring(L, 1);

     char *s2;

     unsigned long n;

     luaL_argcheck(L, 2 <= base && base <= 36, 2, "base out of range");

     n = strtoul(s1, &s2, base);

     if (s1 != s2) {  /* at least one valid digit? */

       while (isspace((unsigned char)(*s2))) s2++;  /* skip trailing spaces */

       if (*s2 == '\0') {  /* no invalid trailing characters? */

         lua_pushnumber(L, (lua_Number)n);

         return 1;

       }

     }

   }

   lua_pushnil(L);  /* else not a number */

   return 1;

 }

 

 

 static int luaB_error (lua_State *L) {

   int level = luaL_optint(L, 2, 1);

   lua_settop(L, 1);

   if (lua_isstring(L, 1) && level > 0) {  /* add extra information? */

     luaL_where(L, level);

     lua_pushvalue(L, 1);

     lua_concat(L, 2);

   }

   return lua_error(L);

 }

 

 

 static int luaB_getmetatable (lua_State *L) {

   luaL_checkany(L, 1);

   if (!lua_getmetatable(L, 1)) {

     lua_pushnil(L);

     return 1;  /* no metatable */

   }

   luaL_getmetafield(L, 1, "__metatable");

   return 1;  /* returns either __metatable field (if present) or metatable */

 }

 

 

 static int luaB_setmetatable (lua_State *L) {

   int t = lua_type(L, 2);

   luaL_checktype(L, 1, LUA_TTABLE);

   luaL_argcheck(L, t == LUA_TNIL || t == LUA_TTABLE, 2,

                     "nil or table expected");

   if (luaL_getmetafield(L, 1, "__metatable"))

     luaL_error(L, "cannot change a protected metatable");

   lua_settop(L, 2);

   lua_setmetatable(L, 1);

   return 1;

 }

 

 

 static void getfunc (lua_State *L, int opt) {

   if (lua_isfunction(L, 1)) lua_pushvalue(L, 1);

   else {

     lua_Debug ar;

     int level = opt ? luaL_optint(L, 1, 1) : luaL_checkint(L, 1);

     luaL_argcheck(L, level >= 0, 1, "level must be non-negative");

     if (lua_getstack(L, level, &ar) == 0)

       luaL_argerror(L, 1, "invalid level");

     lua_getinfo(L, "f", &ar);

     if (lua_isnil(L, -1))

       luaL_error(L, "no function environment for tail call at level %d",

                     level);

   }

 }

 

 

 static int luaB_getfenv (lua_State *L) {

   getfunc(L, 1);

   if (lua_iscfunction(L, -1))  /* is a C function? */

     lua_pushvalue(L, LUA_GLOBALSINDEX);  /* return the thread's global env. */

   else

     lua_getfenv(L, -1);

   return 1;

 }

 

 

 static int luaB_setfenv (lua_State *L) {

   luaL_checktype(L, 2, LUA_TTABLE);

   getfunc(L, 0);

   lua_pushvalue(L, 2);

   if (lua_isnumber(L, 1) && lua_tonumber(L, 1) == 0) {

     /* change environment of current thread */

     lua_pushthread(L);

     lua_insert(L, -2);

     lua_setfenv(L, -2);

     return 0;

   }

   else if (lua_iscfunction(L, -2) || lua_setfenv(L, -2) == 0)

     luaL_error(L,

           LUA_QL("setfenv") " cannot change environment of given object");

   return 1;

 }

 

 

 static int luaB_rawequal (lua_State *L) {

   luaL_checkany(L, 1);

   luaL_checkany(L, 2);

   lua_pushboolean(L, lua_rawequal(L, 1, 2));

   return 1;

 }

 

 

 static int luaB_rawget (lua_State *L) {

   luaL_checktype(L, 1, LUA_TTABLE);

   luaL_checkany(L, 2);

   lua_settop(L, 2);

   lua_rawget(L, 1);

   return 1;

 }

 

 static int luaB_rawset (lua_State *L) {

   luaL_checktype(L, 1, LUA_TTABLE);

   luaL_checkany(L, 2);

   luaL_checkany(L, 3);

   lua_settop(L, 3);

   lua_rawset(L, 1);

   return 1;

 }

 

 

 static int luaB_gcinfo (lua_State *L) {

   lua_pushinteger(L, lua_getgccount(L));

   return 1;

 }

 

 

 static int luaB_collectgarbage (lua_State *L) {

   static const char *const opts[] = {"stop", "restart", "collect",

     "count", "step", "setpause", "setstepmul", NULL};

   static const int optsnum[] = {LUA_GCSTOP, LUA_GCRESTART, LUA_GCCOLLECT,

     LUA_GCCOUNT, LUA_GCSTEP, LUA_GCSETPAUSE, LUA_GCSETSTEPMUL};

   int o = luaL_checkoption(L, 1, "collect", opts);

   int ex = luaL_optint(L, 2, 0);

   int res = lua_gc(L, optsnum[o], ex);

   switch (optsnum[o]) {

     case LUA_GCCOUNT: {

       int b = lua_gc(L, LUA_GCCOUNTB, 0);

       lua_pushnumber(L, res + ((lua_Number)b/1024));

       return 1;

     }

     case LUA_GCSTEP: {

       lua_pushboolean(L, res);

       return 1;

     }

     default: {

       lua_pushnumber(L, res);

       return 1;

     }

   }

 }

 

 

 static int luaB_type (lua_State *L) {

   luaL_checkany(L, 1);

   lua_pushstring(L, luaL_typename(L, 1));

   return 1;

 }

 

 

 static int luaB_next (lua_State *L) {

   luaL_checktype(L, 1, LUA_TTABLE);

   lua_settop(L, 2);  /* create a 2nd argument if there isn't one */

   if (lua_next(L, 1))

     return 2;

   else {

     lua_pushnil(L);

     return 1;

   }

 }

 

 

 static int luaB_pairs (lua_State *L) {

   luaL_checktype(L, 1, LUA_TTABLE);

   lua_pushvalue(L, lua_upvalueindex(1));  /* return generator, */

   lua_pushvalue(L, 1);  /* state, */

   lua_pushnil(L);  /* and initial value */

   return 3;

 }

 

 

 static int ipairsaux (lua_State *L) {

   int i = luaL_checkint(L, 2);

   luaL_checktype(L, 1, LUA_TTABLE);

   i++;  /* next value */

   lua_pushinteger(L, i);

   lua_rawgeti(L, 1, i);

   return (lua_isnil(L, -1)) ? 0 : 2;

 }

 

 

 static int luaB_ipairs (lua_State *L) {

   luaL_checktype(L, 1, LUA_TTABLE);

   lua_pushvalue(L, lua_upvalueindex(1));  /* return generator, */

   lua_pushvalue(L, 1);  /* state, */

   lua_pushinteger(L, 0);  /* and initial value */

   return 3;

 }

 

 

 static int load_aux (lua_State *L, int status) {

   if (status == 0)  /* OK? */

     return 1;

   else {

     lua_pushnil(L);

     lua_insert(L, -2);  /* put before error message */

     return 2;  /* return nil plus error message */

   }

 }

 

 

 static int luaB_loadstring (lua_State *L) {

   size_t l;

   const char *s = luaL_checklstring(L, 1, &l);

   const char *chunkname = luaL_optstring(L, 2, s);

   return load_aux(L, luaL_loadbuffer(L, s, l, chunkname));

 }

 

 

 static int luaB_loadfile (lua_State *L) {

   const char *fname = luaL_optstring(L, 1, NULL);

   return load_aux(L, luaL_loadfile(L, fname));

 }

 

 

 /*

 ** Reader for generic `load' function: `lua_load' uses the

 ** stack for internal stuff, so the reader cannot change the

 ** stack top. Instead, it keeps its resulting string in a

 ** reserved slot inside the stack.

 */

 static const char *generic_reader (lua_State *L, void *ud, size_t *size) {

   (void)ud;  /* to avoid warnings */

   luaL_checkstack(L, 2, "too many nested functions");

   lua_pushvalue(L, 1);  /* get function */

   lua_call(L, 0, 1);  /* call it */

   if (lua_isnil(L, -1)) {

     *size = 0;

     return NULL;

   }

   else if (lua_isstring(L, -1)) {

     lua_replace(L, 3);  /* save string in a reserved stack slot */

     return lua_tolstring(L, 3, size);

   }

   else luaL_error(L, "reader function must return a string");

   return NULL;  /* to avoid warnings */

 }

 

 

 static int luaB_load (lua_State *L) {

   int status;

   const char *cname = luaL_optstring(L, 2, "=(load)");

   luaL_checktype(L, 1, LUA_TFUNCTION);

   lua_settop(L, 3);  /* function, eventual name, plus one reserved slot */

   status = lua_load(L, generic_reader, NULL, cname);

   return load_aux(L, status);

 }

 

 

 static int luaB_dofile (lua_State *L) {

   const char *fname = luaL_optstring(L, 1, NULL);

   int n = lua_gettop(L);

   if (luaL_loadfile(L, fname) != 0) lua_error(L);

   lua_call(L, 0, LUA_MULTRET);

   return lua_gettop(L) - n;

 }

 

 

 static int luaB_assert (lua_State *L) {

   luaL_checkany(L, 1);

   if (!lua_toboolean(L, 1))

     return luaL_error(L, "%s", luaL_optstring(L, 2, "assertion failed!"));

   return lua_gettop(L);

 }

 

 

 static int luaB_unpack (lua_State *L) {

   int i, e, n;

   luaL_checktype(L, 1, LUA_TTABLE);

   i = luaL_optint(L, 2, 1);

   e = luaL_opt(L, luaL_checkint, 3, luaL_getn(L, 1));

   if (i > e) return 0;  /* empty range */

   n = e - i + 1;  /* number of elements */

   if (n <= 0 || !lua_checkstack(L, n))  /* n <= 0 means arith. overflow */

     return luaL_error(L, "too many results to unpack");

   lua_rawgeti(L, 1, i);  /* push arg[i] (avoiding overflow problems) */

   while (i++ < e)  /* push arg[i + 1...e] */

     lua_rawgeti(L, 1, i);

   return n;

 }

 

 

 static int luaB_select (lua_State *L) {

   int n = lua_gettop(L);

   if (lua_type(L, 1) == LUA_TSTRING && *lua_tostring(L, 1) == '#') {

     lua_pushinteger(L, n-1);

     return 1;

   }

   else {

     int i = luaL_checkint(L, 1);

     if (i < 0) i = n + i;

     else if (i > n) i = n;

     luaL_argcheck(L, 1 <= i, 1, "index out of range");

     return n - i;

   }

 }

 

 

 static int luaB_pcall (lua_State *L) {

   int status;

   luaL_checkany(L, 1);

   status = lua_pcall(L, lua_gettop(L) - 1, LUA_MULTRET, 0);

   lua_pushboolean(L, (status == 0));

   lua_insert(L, 1);

   return lua_gettop(L);  /* return status + all results */

 }

 

 

 static int luaB_xpcall (lua_State *L) {

   int status;

   luaL_checkany(L, 2);

   lua_settop(L, 2);

   lua_insert(L, 1);  /* put error function under function to be called */

   status = lua_pcall(L, 0, LUA_MULTRET, 1);

   lua_pushboolean(L, (status == 0));

   lua_replace(L, 1);

   return lua_gettop(L);  /* return status + all results */

 }

 

 

 static int luaB_tostring (lua_State *L) {

   luaL_checkany(L, 1);

   if (luaL_callmeta(L, 1, "__tostring"))  /* is there a metafield? */

     return 1;  /* use its value */

   switch (lua_type(L, 1)) {

     case LUA_TNUMBER:

       lua_pushstring(L, lua_tostring(L, 1));

       break;

     case LUA_TSTRING:

       lua_pushvalue(L, 1);

       break;

     case LUA_TBOOLEAN:

       lua_pushstring(L, (lua_toboolean(L, 1) ? "true" : "false"));

       break;

     case LUA_TNIL:

       lua_pushliteral(L, "nil");

       break;

     default:

       lua_pushfstring(L, "%s: %p", luaL_typename(L, 1), lua_topointer(L, 1));

       break;

   }

   return 1;

 }

 

 

 static int luaB_newproxy (lua_State *L) {

   lua_settop(L, 1);

   lua_newuserdata(L, 0);  /* create proxy */

   if (lua_toboolean(L, 1) == 0)

     return 1;  /* no metatable */

   else if (lua_isboolean(L, 1)) {

     lua_newtable(L);  /* create a new metatable `m' ... */

     lua_pushvalue(L, -1);  /* ... and mark `m' as a valid metatable */

     lua_pushboolean(L, 1);

     lua_rawset(L, lua_upvalueindex(1));  /* weaktable[m] = true */

   }

   else {

     int validproxy = 0;  /* to check if weaktable[metatable(u)] == true */

     if (lua_getmetatable(L, 1)) {

       lua_rawget(L, lua_upvalueindex(1));

       validproxy = lua_toboolean(L, -1);

       lua_pop(L, 1);  /* remove value */

     }

     luaL_argcheck(L, validproxy, 1, "boolean or proxy expected");

     lua_getmetatable(L, 1);  /* metatable is valid; get it */

   }

   lua_setmetatable(L, 2);

   return 1;

 }

 

 

 static const luaL_Reg base_funcs[] = {

   {"assert", luaB_assert},

   {"collectgarbage", luaB_collectgarbage},

   {"dofile", luaB_dofile},

   {"error", luaB_error},

   {"gcinfo", luaB_gcinfo},

   {"getfenv", luaB_getfenv},

   {"getmetatable", luaB_getmetatable},

   {"loadfile", luaB_loadfile},

   {"load", luaB_load},

   {"loadstring", luaB_loadstring},

   {"next", luaB_next},

   {"pcall", luaB_pcall},

   {"print", luaB_print},

   {"rawequal", luaB_rawequal},

   {"rawget", luaB_rawget},

   {"rawset", luaB_rawset},

   {"select", luaB_select},

   {"setfenv", luaB_setfenv},

   {"setmetatable", luaB_setmetatable},

   {"tonumber", luaB_tonumber},

   {"tostring", luaB_tostring},

   {"type", luaB_type},

   {"unpack", luaB_unpack},

   {"xpcall", luaB_xpcall},

   {NULL, NULL}

 };

 

 

 /*

 ** {======================================================

 ** Coroutine library

 ** =======================================================

 */

 

 #define CO_RUN	0	/* running */

 #define CO_SUS	1	/* suspended */

 #define CO_NOR	2	/* 'normal' (it resumed another coroutine) */

 #define CO_DEAD	3

 

 static const char *const statnames[] =

     {"running", "suspended", "normal", "dead"};

 

 static int costatus (lua_State *L, lua_State *co) {

   if (L == co) return CO_RUN;

   switch (lua_status(co)) {

     case LUA_YIELD:

       return CO_SUS;

     case 0: {

       lua_Debug ar;

       if (lua_getstack(co, 0, &ar) > 0)  /* does it have frames? */

         return CO_NOR;  /* it is running */

       else if (lua_gettop(co) == 0)

           return CO_DEAD;

       else

         return CO_SUS;  /* initial state */

     }

     default:  /* some error occured */

       return CO_DEAD;

   }

 }

 

 

 static int luaB_costatus (lua_State *L) {

   lua_State *co = lua_tothread(L, 1);

   luaL_argcheck(L, co, 1, "coroutine expected");

   lua_pushstring(L, statnames[costatus(L, co)]);

   return 1;

 }

 

 

 static int auxresume (lua_State *L, lua_State *co, int narg) {

   int status = costatus(L, co);

   if (!lua_checkstack(co, narg))

     luaL_error(L, "too many arguments to resume");

   if (status != CO_SUS) {

     lua_pushfstring(L, "cannot resume %s coroutine", statnames[status]);

     return -1;  /* error flag */

   }

   lua_xmove(L, co, narg);

   lua_setlevel(L, co);

   status = lua_resume(co, narg);

   if (status == 0 || status == LUA_YIELD) {

     int nres = lua_gettop(co);

     if (!lua_checkstack(L, nres + 1))

       luaL_error(L, "too many results to resume");

     lua_xmove(co, L, nres);  /* move yielded values */

     return nres;

   }

   else {

     lua_xmove(co, L, 1);  /* move error message */

     return -1;  /* error flag */

   }

 }

 

 

 static int luaB_coresume (lua_State *L) {

   lua_State *co = lua_tothread(L, 1);

   int r;

   luaL_argcheck(L, co, 1, "coroutine expected");

   r = auxresume(L, co, lua_gettop(L) - 1);

   if (r < 0) {

     lua_pushboolean(L, 0);

     lua_insert(L, -2);

     return 2;  /* return false + error message */

   }

   else {

     lua_pushboolean(L, 1);

     lua_insert(L, -(r + 1));

     return r + 1;  /* return true + `resume' returns */

   }

 }

 

 

 static int luaB_auxwrap (lua_State *L) {

   lua_State *co = lua_tothread(L, lua_upvalueindex(1));

   int r = auxresume(L, co, lua_gettop(L));

   if (r < 0) {

     if (lua_isstring(L, -1)) {  /* error object is a string? */

       luaL_where(L, 1);  /* add extra info */

       lua_insert(L, -2);

       lua_concat(L, 2);

     }

     lua_error(L);  /* propagate error */

   }

   return r;

 }

 

 

 static int luaB_cocreate (lua_State *L) {

   lua_State *NL = lua_newthread(L);

   luaL_argcheck(L, lua_isfunction(L, 1) && !lua_iscfunction(L, 1), 1,

     "Lua function expected");

   lua_pushvalue(L, 1);  /* move function to top */

   lua_xmove(L, NL, 1);  /* move function from L to NL */

   return 1;

 }

 

 

 static int luaB_cowrap (lua_State *L) {

   luaB_cocreate(L);

   lua_pushcclosure(L, luaB_auxwrap, 1);

   return 1;

 }

 

 

 static int luaB_yield (lua_State *L) {

   return lua_yield(L, lua_gettop(L));

 }

 

 

 static int luaB_corunning (lua_State *L) {

   if (lua_pushthread(L))

     lua_pushnil(L);  /* main thread is not a coroutine */

   return 1;

 }

 

 

 static const luaL_Reg co_funcs[] = {

   {"create", luaB_cocreate},

   {"resume", luaB_coresume},

   {"running", luaB_corunning},

   {"status", luaB_costatus},

   {"wrap", luaB_cowrap},

   {"yield", luaB_yield},

   {NULL, NULL}

 };

 

 /* }====================================================== */

 

 

 static void auxopen (lua_State *L, const char *name,

                      lua_CFunction f, lua_CFunction u) {

   lua_pushcfunction(L, u);

   lua_pushcclosure(L, f, 1);

   lua_setfield(L, -2, name);

 }

 

 

 static void base_open (lua_State *L) {

   /* set global _G */

   lua_pushvalue(L, LUA_GLOBALSINDEX);

   lua_setglobal(L, "_G");

   /* open lib into global table */

   luaL_register(L, "_G", base_funcs);

   lua_pushliteral(L, LUA_VERSION);

   lua_setglobal(L, "_VERSION");  /* set global _VERSION */

   /* `ipairs' and `pairs' need auxliliary functions as upvalues */

   auxopen(L, "ipairs", luaB_ipairs, ipairsaux);

   auxopen(L, "pairs", luaB_pairs, luaB_next);

   /* `newproxy' needs a weaktable as upvalue */

   lua_createtable(L, 0, 1);  /* new table `w' */

   lua_pushvalue(L, -1);  /* `w' will be its own metatable */

   lua_setmetatable(L, -2);

   lua_pushliteral(L, "kv");

   lua_setfield(L, -2, "__mode");  /* metatable(w).__mode = "kv" */

   lua_pushcclosure(L, luaB_newproxy, 1);

   lua_setglobal(L, "newproxy");  /* set global `newproxy' */

 }

 

 

 LUALIB_API int luaopen_base (lua_State *L) {

   base_open(L);

   luaL_register(L, LUA_COLIBNAME, co_funcs);

   return 2;

 }