lbaselib.c

小游戏 linux very happy

/*
** $Id: lbaselib.c,v 1.2 2002/07/12 07:49:04 jcatki Exp $
** Basic library
** See Copyright Notice in lua.h
*/



#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "lua.h"

#include "lauxlib.h"
#include "luadebug.h"
#include "lualib.h"



/*
** If your system does not support `stderr', redefine this function, or
** redefine _ERRORMESSAGE so that it won't need _ALERT.
*/
static int luaB__ALERT (lua_State *L) {
  fputs(luaL_check_string(L, 1), stderr);
  return 0;
}


/*
** Basic implementation of _ERRORMESSAGE.
** The library `liolib' redefines _ERRORMESSAGE for better error information.
*/
static int luaB__ERRORMESSAGE (lua_State *L) {
  luaL_checktype(L, 1, LUA_TSTRING);
  lua_getglobal(L, LUA_ALERT);
  if (lua_isfunction(L, -1)) {  /* avoid error loop if _ALERT is not defined */
    lua_Debug ar;
    lua_pushstring(L, "error: ");
    lua_pushvalue(L, 1);
    if (lua_getstack(L, 1, &ar)) {
      lua_getinfo(L, "Sl", &ar);
      if (ar.source && ar.currentline > 0) {
        char buff[100];
        sprintf(buff, "\n  <%.70s: line %d>", ar.short_src, ar.currentline);
        lua_pushstring(L, buff);
        lua_concat(L, 2);
      }
    }
    lua_pushstring(L, "\n");
    lua_concat(L, 3);
    lua_rawcall(L, 1, 0);
  }
  return 0;
}


/*
** 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_rawcall(L, 1, 1);
    s = lua_tostring(L, -1);  /* get result */
    if (s == NULL)
      lua_error(L, "`tostring' must return a string to `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_opt_int(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_check_string(L, 1);
    char *s2;
    unsigned long n;
    luaL_arg_check(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, n);
        return 1;
      }
    }
  }
  lua_pushnil(L);  /* else not a number */
  return 1;
}


static int luaB_error (lua_State *L) {
  lua_error(L, luaL_opt_string(L, 1, NULL));
  return 0;  /* to avoid warnings */
}

static int luaB_setglobal (lua_State *L) {
  luaL_checkany(L, 2);
  lua_setglobal(L, luaL_check_string(L, 1));
  return 0;
}

static int luaB_getglobal (lua_State *L) {
  lua_getglobal(L, luaL_check_string(L, 1));
  return 1;
}

static int luaB_tag (lua_State *L) {
  luaL_checkany(L, 1);
  lua_pushnumber(L, lua_tag(L, 1));
  return 1;
}

static int luaB_settag (lua_State *L) {
  luaL_checktype(L, 1, LUA_TTABLE);
  lua_pushvalue(L, 1);  /* push table */
  lua_settag(L, luaL_check_int(L, 2));
  return 1;  /* return table */
}

static int luaB_newtag (lua_State *L) {
  lua_pushnumber(L, lua_newtag(L));
  return 1;
}

static int luaB_copytagmethods (lua_State *L) {
  lua_pushnumber(L, lua_copytagmethods(L, luaL_check_int(L, 1),
                                          luaL_check_int(L, 2)));
  return 1;
}

static int luaB_globals (lua_State *L) {
  lua_getglobals(L);  /* value to be returned */
  if (!lua_isnull(L, 1)) {
    luaL_checktype(L, 1, LUA_TTABLE);
    lua_pushvalue(L, 1);  /* new table of globals */
    lua_setglobals(L);
  }
  return 1;
}

static int luaB_rawget (lua_State *L) {
  luaL_checktype(L, 1, LUA_TTABLE);
  luaL_checkany(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_rawset(L, 1);
  return 1;
}

static int luaB_settagmethod (lua_State *L) {
  int tag = luaL_check_int(L, 1);
  const char *event = luaL_check_string(L, 2);
  luaL_arg_check(L, lua_isfunction(L, 3) || lua_isnil(L, 3), 3,
                 "function or nil expected");
  if (strcmp(event, "gc") == 0)
    lua_error(L, "deprecated use: cannot set the `gc' tag method from Lua");
  lua_gettagmethod(L, tag, event);
  lua_pushvalue(L, 3);
  lua_settagmethod(L, tag, event);
  return 1;
}


static int luaB_gettagmethod (lua_State *L) {
  int tag = luaL_check_int(L, 1);
  const char *event = luaL_check_string(L, 2);
  if (strcmp(event, "gc") == 0)
    lua_error(L, "deprecated use: cannot get the `gc' tag method from Lua");
  lua_gettagmethod(L, tag, event);
  return 1;
}


static int luaB_gcinfo (lua_State *L) {
  lua_pushnumber(L, lua_getgccount(L));
  lua_pushnumber(L, lua_getgcthreshold(L));
  return 2;
}


static int luaB_collectgarbage (lua_State *L) {
  lua_setgcthreshold(L, luaL_opt_int(L, 1, 0));
  return 0;
}


static int luaB_type (lua_State *L) {
  luaL_checkany(L, 1);
  lua_pushstring(L, lua_typename(L, lua_type(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 passresults (lua_State *L, int status, int oldtop) {
  static const char *const errornames[] =
    {"ok", "run-time error", "file error", "syntax error",
     "memory error", "error in error handling"};
  if (status == 0) {
    int nresults = lua_gettop(L) - oldtop;
    if (nresults > 0)
      return nresults;  /* results are already on the stack */
    else {
      lua_pushuserdata(L, NULL);  /* at least one result to signal no errors */
      return 1;
    }
  }
  else {  /* error */
    lua_pushnil(L);
    lua_pushstring(L, errornames[status]);  /* error code */
    return 2;
  }
}

static int luaB_dostring (lua_State *L) {
  int oldtop = lua_gettop(L);
  size_t l;
  const char *s = luaL_check_lstr(L, 1, &l);
  if (*s == '\33')  /* binary files start with ESC... */
    lua_error(L, "`dostring' cannot run pre-compiled code");
  return passresults(L, lua_dobuffer(L, s, l, luaL_opt_string(L, 2, s)), oldtop);
}


static int luaB_dofile (lua_State *L) {
  int oldtop = lua_gettop(L);
  const char *fname = luaL_opt_string(L, 1, NULL);
  return passresults(L, lua_dofile(L, fname), oldtop);
}


static int luaB_call (lua_State *L) {
  int oldtop;
  const char *options = luaL_opt_string(L, 3, "");
  int err = 0;  /* index of old error method */
  int i, status;
  int n;
  luaL_checktype(L, 2, LUA_TTABLE);
  n = lua_getn(L, 2);
  if (!lua_isnull(L, 4)) {  /* set new error method */
    lua_getglobal(L, LUA_ERRORMESSAGE);
    err = lua_gettop(L);  /* get index */
    lua_pushvalue(L, 4);
    lua_setglobal(L, LUA_ERRORMESSAGE);
  }
  oldtop = lua_gettop(L);  /* top before function-call preparation */
  /* push function */
  lua_pushvalue(L, 1);
  luaL_checkstack(L, n, "too many arguments");
  for (i=0; i<n; i++)  /* push arg[1...n] */
    lua_rawgeti(L, 2, i+1);
  status = lua_call(L, n, LUA_MULTRET);
  if (err != 0) {  /* restore old error method */
    lua_pushvalue(L, err);
    lua_setglobal(L, LUA_ERRORMESSAGE);
  }
  if (status != 0) {  /* error in call? */
    if (strchr(options, 'x'))
      lua_pushnil(L);  /* return nil to signal the error */
    else
      lua_error(L, NULL);  /* propagate error without additional messages */
    return 1;
  }
  if (strchr(options, 'p'))  /* pack results? */
    lua_error(L, "deprecated option `p' in `call'");
  return lua_gettop(L) - oldtop;  /* results are already on the stack */
}


static int luaB_tostring (lua_State *L) {
  char buff[64];
  switch (lua_type(L, 1)) {
    case LUA_TNUMBER:
      lua_pushstring(L, lua_tostring(L, 1));
      return 1;
    case LUA_TSTRING:
      lua_pushvalue(L, 1);
      return 1;
    case LUA_TTABLE:
      sprintf(buff, "table: %p", lua_topointer(L, 1));
      break;
    case LUA_TFUNCTION:
      sprintf(buff, "function: %p", lua_topointer(L, 1));
      break;
    case LUA_TUSERDATA: