/*** $Id: lobject.c,v 2.22 2006/02/10 17:43:52 roberto Exp $** Some generic functions over Lua objects** See Copyright Notice in lua.h*/#include <ctype.h>#include <stdarg.h>#include <stdio.h>#include <stdlib.h>#include <string.h>#define lobject_c#define LUA_CORE#include "lua.h"#include "ldo.h"#include "lmem.h"#include "lobject.h"#include "lstate.h"#include "lstring.h"#include "lvm.h"const TValue luaO_nilobject_ = {{NULL}, LUA_TNIL};/*** converts an integer to a "floating point byte", represented as** (eeeeexxx), where the real value is (1xxx) * 2^(eeeee - 1) if** eeeee != 0 and (xxx) otherwise.*/int luaO_int2fb (unsigned int x) {  int e = 0;  /* expoent */  while (x >= 16) {    x = (x+1) >> 1;    e++;  }  if (x < 8) return x;  else return ((e+1) << 3) | (cast_int(x) - 8);}/* converts back */int luaO_fb2int (int x) {  int e = (x >> 3) & 31;  if (e == 0) return x;  else return ((x & 7)+8) << (e - 1);}int luaO_log2 (unsigned int x) {  static const lu_byte log_2[256] = {    0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,    6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,    7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,    7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,    8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,    8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,    8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,    8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8  };  int l = -1;  while (x >= 256) { l += 8; x >>= 8; }  return l + log_2[x];}int luaO_rawequalObj (const TValue *t1, const TValue *t2) {  if (ttype(t1) != ttype(t2)) return 0;  else switch (ttype(t1)) {    case LUA_TNIL:      return 1;    case LUA_TNUMBER:      return luai_numeq(nvalue(t1), nvalue(t2));    case LUA_TBOOLEAN:      return bvalue(t1) == bvalue(t2);  /* boolean true must be 1 !! */    case LUA_TLIGHTUSERDATA:      return pvalue(t1) == pvalue(t2);    default:      lua_assert(iscollectable(t1));      return gcvalue(t1) == gcvalue(t2);  }}int luaO_str2d (const char *s, lua_Number *result) {  char *endptr;  *result = lua_str2number(s, &endptr);  if (endptr == s) return 0;  /* conversion failed */  if (*endptr == 'x' || *endptr == 'X')  /* maybe an hexadecimal constant? */    *result = cast_num(strtoul(s, &endptr, 16));  if (*endptr == '\0') return 1;  /* most common case */  while (isspace(cast(unsigned char, *endptr))) endptr++;  if (*endptr != '\0') return 0;  /* invalid trailing characters? */  return 1;}static void pushstr (lua_State *L, const char *str) {  setsvalue2s(L, L->top, luaS_new(L, str));  incr_top(L);}/* this function handles only `%d', `%c', %f, %p, and `%s' formats */const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) {  int n = 1;  pushstr(L, "");  for (;;) {    const char *e = strchr(fmt, '%');    if (e == NULL) break;    setsvalue2s(L, L->top, luaS_newlstr(L, fmt, e-fmt));    incr_top(L);    switch (*(e+1)) {      case 's': {        const char *s = va_arg(argp, char *);        if (s == NULL) s = "(null)";        pushstr(L, s);        break;      }      case 'c': {        char buff[2];        buff[0] = cast(char, va_arg(argp, int));        buff[1] = '\0';        pushstr(L, buff);        break;      }      case 'd': {        setnvalue(L->top, cast_num(va_arg(argp, int)));        incr_top(L);        break;      }      case 'f': {        setnvalue(L->top, cast_num(va_arg(argp, l_uacNumber)));        incr_top(L);        break;      }      case 'p': {        char buff[4*sizeof(void *) + 8]; /* should be enough space for a `%p' */        sprintf(buff, "%p", va_arg(argp, void *));        pushstr(L, buff);        break;      }      case '%': {        pushstr(L, "%");        break;      }      default: {        char buff[3];        buff[0] = '%';        buff[1] = *(e+1);        buff[2] = '\0';        pushstr(L, buff);        break;      }    }    n += 2;    fmt = e+2;  }  pushstr(L, fmt);  luaV_concat(L, n+1, cast_int(L->top - L->base) - 1);  L->top -= n;  return svalue(L->top - 1);}const char *luaO_pushfstring (lua_State *L, const char *fmt, ...) {  const char *msg;  va_list argp;  va_start(argp, fmt);  msg = luaO_pushvfstring(L, fmt, argp);  va_end(argp);  return msg;}void luaO_chunkid (char *out, const char *source, size_t bufflen) {  if (*source == '=') {    strncpy(out, source+1, bufflen);  /* remove first char */    out[bufflen-1] = '\0';  /* ensures null termination */  }  else {  /* out = "source", or "...source" */    if (*source == '@') {      size_t l;      source++;  /* skip the `@' */      bufflen -= sizeof(" '...' ");      l = strlen(source);      strcpy(out, "");      if (l > bufflen) {        source += (l-bufflen);  /* get last part of file name */        strcat(out, "...");      }      strcat(out, source);    }    else {  /* out = [string "string"] */      size_t len = strcspn(source, "\n\r");  /* stop at first newline */      bufflen -= sizeof(" [string \"...\"] ");      if (len > bufflen) len = bufflen;      strcpy(out, "[string \"");      if (source[len] != '\0') {  /* must truncate? */        strncat(out, source, len);        strcat(out, "...");      }      else        strcat(out, source);      strcat(out, "\"]");    }  }}