/*** $Id: lbaselib.c,v 1.274 2012/04/27 14:13:19 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"  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;    size_t l;    lua_pushvalue(L, -1);  /* function to be called */    lua_pushvalue(L, i);   /* value to print */    lua_call(L, 1, 1);    s = lua_tolstring(L, -1, &l);  /* get result */    if (s == NULL)      return luaL_error(L,         LUA_QL("tostring") " must return a string to " LUA_QL("print"));    if (i>1) luai_writestring("\t", 1);    luai_writestring(s, l);    lua_pop(L, 1);  /* pop result */  }  luai_writeline();  return 0;}  #define SPACECHARS	" \f\n\r\t\v" static int luaB_tonumber (lua_State *L) {  if (lua_isnoneornil(L, 2)) {  /* standard conversion */    int isnum;    lua_Number n = lua_tonumberx(L, 1, &isnum);    if (isnum) {      lua_pushnumber(L, n);      return 1;    }  /* else not a number; must be something */    luaL_checkany(L, 1);  }  else {    size_t l;    const char *s = luaL_checklstring(L, 1, &l);    const char *e = s + l;  /* end point for 's' */    int base = luaL_checkint(L, 2);    int neg = 0;    luaL_argcheck(L, 2 <= base && base <= 36, 2, "base out of range");    s += strspn(s, SPACECHARS);  /* skip initial spaces */    if (*s == '-') { s++; neg = 1; }  /* handle signal */    else if (*s == '+') s++;    if (isalnum((unsigned char)*s)) {      lua_Number n = 0;      do {        int digit = (isdigit((unsigned char)*s)) ? *s - '0'                       : toupper((unsigned char)*s) - 'A' + 10;        if (digit >= base) break;  /* invalid numeral; force a fail */        n = n * (lua_Number)base + (lua_Number)digit;        s++;      } while (isalnum((unsigned char)*s));      s += strspn(s, SPACECHARS);  /* skip trailing spaces */      if (s == e) {  /* no invalid trailing characters? */        lua_pushnumber(L, (neg) ? -n : n);        return 1;      }  /* else not a number */    }  /* else not a number */  }  lua_pushnil(L);  /* 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"))    return luaL_error(L, "cannot change a protected metatable");  lua_settop(L, 2);  lua_setmetatable(L, 1);  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_rawlen (lua_State *L) {  int t = lua_type(L, 1);  luaL_argcheck(L, t == LUA_TTABLE || t == LUA_TSTRING, 1,                   "table or string expected");  lua_pushinteger(L, lua_rawlen(L, 1));  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_collectgarbage (lua_State *L) {  static const char *const opts[] = {"stop", "restart", "collect",    "count", "step", "setpause", "setstepmul",    "setmajorinc", "isrunning", "generational", "incremental", NULL};  static const int optsnum[] = {LUA_GCSTOP, LUA_GCRESTART, LUA_GCCOLLECT,    LUA_GCCOUNT, LUA_GCSTEP, LUA_GCSETPAUSE, LUA_GCSETSTEPMUL,    LUA_GCSETMAJORINC, LUA_GCISRUNNING, LUA_GCGEN, LUA_GCINC};  int o = optsnum[luaL_checkoption(L, 1, "collect", opts)];  int ex = luaL_optint(L, 2, 0);  int res = lua_gc(L, o, ex);  switch (o) {    case LUA_GCCOUNT: {      int b = lua_gc(L, LUA_GCCOUNTB, 0);      lua_pushnumber(L, res + ((lua_Number)b/1024));      lua_pushinteger(L, b);      return 2;    }    case LUA_GCSTEP: case LUA_GCISRUNNING: {      lua_pushboolean(L, res);      return 1;    }    default: {      lua_pushinteger(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 pairsmeta (lua_State *L, const char *method, int iszero,                      lua_CFunction iter) {  if (!luaL_getmetafield(L, 1, method)) {  /* no metamethod? */    luaL_checktype(L, 1, LUA_TTABLE);  /* argument must be a table */    lua_pushcfunction(L, iter);  /* will return generator, */    lua_pushvalue(L, 1);  /* state, */    if (iszero) lua_pushinteger(L, 0);  /* and initial value */    else lua_pushnil(L);  }  else {    lua_pushvalue(L, 1);  /* argument 'self' to metamethod */    lua_call(L, 1, 3);  /* get 3 values from metamethod */  }  return 3;}  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) {  return pairsmeta(L, "__pairs", 0, luaB_next);}  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)) ? 1 : 2;}  static int luaB_ipairs (lua_State *L) {  return pairsmeta(L, "__ipairs", 1, ipairsaux);}  static int load_aux (lua_State *L, int status) {  if (status == LUA_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_loadfile (lua_State *L) {  const char *fname = luaL_optstring(L, 1, NULL);  const char *mode = luaL_optstring(L, 2, NULL);  int env = !lua_isnone(L, 3);  /* 'env' parameter? */  int status = luaL_loadfilex(L, fname, mode);  if (status == LUA_OK && env) {  /* 'env' parameter? */    lua_pushvalue(L, 3);    lua_setupvalue(L, -2, 1);  /* set it as 1st upvalue of loaded chunk */  }  return load_aux(L, status);}  /*** {======================================================** Generic Read function** =======================================================*/  /*** reserved slot, above all arguments, to hold a copy of the returned** string to avoid it being collected while parsed. 'load' has four** optional arguments (chunk, source name, mode, and environment).*/#define RESERVEDSLOT	5  /*** 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);  /* not used */  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)) {    lua_pop(L, 1);  /* pop result */    *size = 0;    return NULL;  }  else if (!lua_isstring(L, -1))    luaL_error(L, "reader function must return a string");  lua_replace(L, RESERVEDSLOT);  /* save string in reserved slot */  return lua_tolstring(L, RESERVEDSLOT, size);}  static int luaB_load (lua_State *L) {  int status;  size_t l;  int top = lua_gettop(L);  const char *s = lua_tolstring(L, 1, &l);  const char *mode = luaL_optstring(L, 3, "bt");  if (s != NULL) {  /* loading a string? */    const char *chunkname = luaL_optstring(L, 2, s);    status = luaL_loadbufferx(L, s, l, chunkname, mode);  }  else {  /* loading from a reader function */    const char *chunkname = luaL_optstring(L, 2, "=(load)");    luaL_checktype(L, 1, LUA_TFUNCTION);    lua_settop(L, RESERVEDSLOT);  /* create reserved slot */    status = lua_load(L, generic_reader, NULL, chunkname, mode);  }  if (status == LUA_OK && top >= 4) {  /* is there an 'env' argument */    lua_pushvalue(L, 4);  /* environment for loaded function */    lua_setupvalue(L, -2, 1);  /* set it as 1st upvalue */  }  return load_aux(L, status);} /* }====================================================== */  static int dofilecont (lua_State *L) {  return lua_gettop(L) - 1;}  static int luaB_dofile (lua_State *L) {  const char *fname = luaL_optstring(L, 1, NULL);  lua_settop(L, 1);  if (luaL_loadfile(L, fname) != LUA_OK) lua_error(L);  lua_callk(L, 0, LUA_MULTRET, 0, dofilecont);  return dofilecont(L);}  static int luaB_assert (lua_State *L) {  if (!lua_toboolean(L, 1))    return luaL_error(L, "%s", luaL_optstring(L, 2, "assertion failed!"));  return lua_gettop(L);}  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 finishpcall (lua_State *L, int status) {  if (!lua_checkstack(L, 1)) {  /* no space for extra boolean? */    lua_settop(L, 0);  /* create space for return values */    lua_pushboolean(L, 0);    lua_pushstring(L, "stack overflow");    return 2;  /* return false, msg */  }  lua_pushboolean(L, status);  /* first result (status) */  lua_replace(L, 1);  /* put first result in first slot */  return lua_gettop(L);}  static int pcallcont (lua_State *L) {  int status = lua_getctx(L, NULL);  return finishpcall(L, (status == LUA_YIELD));}  static int luaB_pcall (lua_State *L) {  int status;  luaL_checkany(L, 1);  lua_pushnil(L);  lua_insert(L, 1);  /* create space for status result */  status = lua_pcallk(L, lua_gettop(L) - 2, LUA_MULTRET, 0, 0, pcallcont);  return finishpcall(L, (status == LUA_OK));}  static int luaB_xpcall (lua_State *L) {  int status;  int n = lua_gettop(L);  luaL_argcheck(L, n >= 2, 2, "value expected");  lua_pushvalue(L, 1);  /* exchange function... */  lua_copy(L, 2, 1);  /* ...and error handler */  lua_replace(L, 2);  status = lua_pcallk(L, n - 2, LUA_MULTRET, 1, 0, pcallcont);  return finishpcall(L, (status == LUA_OK));}  static int luaB_tostring (lua_State *L) {  luaL_checkany(L, 1);  luaL_tolstring(L, 1, NULL);  return 1;}  static const luaL_Reg base_funcs[] = {  {"assert", luaB_assert},  {"collectgarbage", luaB_collectgarbage},  {"dofile", luaB_dofile},  {"error", luaB_error},  {"getmetatable", luaB_getmetatable},  {"ipairs", luaB_ipairs},  {"loadfile", luaB_loadfile},  {"load", luaB_load},#if defined(LUA_COMPAT_LOADSTRING)  {"loadstring", luaB_load},#endif  {"next", luaB_next},  {"pairs", luaB_pairs},  {"pcall", luaB_pcall},  {"print", luaB_print},  {"rawequal", luaB_rawequal},  {"rawlen", luaB_rawlen},  {"rawget", luaB_rawget},  {"rawset", luaB_rawset},  {"select", luaB_select},  {"setmetatable", luaB_setmetatable},  {"tonumber", luaB_tonumber},  {"tostring", luaB_tostring},  {"type", luaB_type},  {"xpcall", luaB_xpcall},  {NULL, NULL}};  LUAMOD_API int luaopen_base (lua_State *L) {  /* set global _G */  lua_pushglobaltable(L);  lua_pushglobaltable(L);  lua_setfield(L, -2, "_G");  /* open lib into global table */  luaL_setfuncs(L, base_funcs, 0);  lua_pushliteral(L, LUA_VERSION);  lua_setfield(L, -2, "_VERSION");  /* set global _VERSION */  return 1;}