Subversion Repositories Kolibri OS

/*

** $Id: lobject.c,v 2.55 2011/11/30 19:30:16 roberto Exp $

** Some generic functions over Lua objects

** See Copyright Notice in lua.h

*/

#include 

#include 

#include 

#include 

#define lobject_c

#define LUA_CORE

#include "lua.h"

#include "lctype.h"

#include "ldebug.h"

#include "ldo.h"

#include "lmem.h"

#include "lobject.h"

#include "lstate.h"

#include "lstring.h"

#include "lvm.h"

LUAI_DDEF const TValue luaO_nilobject_ = {NILCONSTANT};

/*

** 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;  /* exponent */

  if (x < 8) return x;

  while (x >= 0x10) {

    x = (x+1) >> 1;

    e++;

  }

  return ((e+1) << 3) | (cast_int(x) - 8);

}

/* converts back */

int luaO_fb2int (int x) {

  int e = (x >> 3) & 0x1f;

  if (e == 0) return x;

  else return ((x & 7) + 8) << (e - 1);

}

int luaO_ceillog2 (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 = 0;

  x--;

  while (x >= 256) { l += 8; x >>= 8; }

  return l + log_2[x];

}

lua_Number luaO_arith (int op, lua_Number v1, lua_Number v2) {

  switch (op) {

    case LUA_OPADD: return luai_numadd(NULL, v1, v2);

    case LUA_OPSUB: return luai_numsub(NULL, v1, v2);

    case LUA_OPMUL: return luai_nummul(NULL, v1, v2);

    case LUA_OPDIV: return luai_numdiv(NULL, v1, v2);

    case LUA_OPMOD: return luai_nummod(NULL, v1, v2);

    case LUA_OPPOW: return luai_numpow(NULL, v1, v2);

    case LUA_OPUNM: return luai_numunm(NULL, v1);

    default: lua_assert(0); return 0;

  }

}

int luaO_hexavalue (int c) {

  if (lisdigit(c)) return c - '0';

  else return ltolower(c) - 'a' + 10;

}

#if !defined(lua_strx2number)

#include 

static int isneg (const char **s) {

  if (**s == '-') { (*s)++; return 1; }

  else if (**s == '+') (*s)++;

  return 0;

}

static lua_Number readhexa (const char **s, lua_Number r, int *count) {

  for (; lisxdigit(cast_uchar(**s)); (*s)++) {  /* read integer part */

    r = (r * 16.0) + cast_num(luaO_hexavalue(cast_uchar(**s)));

    (*count)++;

  }

  return r;

}

/*

** convert an hexadecimal numeric string to a number, following

** C99 specification for 'strtod'

*/

static lua_Number lua_strx2number (const char *s, char **endptr) {

  lua_Number r = 0.0;

  int e = 0, i = 0;

  int neg = 0;  /* 1 if number is negative */

  *endptr = cast(char *, s);  /* nothing is valid yet */

  while (lisspace(cast_uchar(*s))) s++;  /* skip initial spaces */

  neg = isneg(&s);  /* check signal */

  if (!(*s == '0' && (*(s + 1) == 'x' || *(s + 1) == 'X')))  /* check '0x' */

    return 0.0;  /* invalid format (no '0x') */

  s += 2;  /* skip '0x' */

  r = readhexa(&s, r, &i);  /* read integer part */

  if (*s == '.') {

    s++;  /* skip dot */

    r = readhexa(&s, r, &e);  /* read fractional part */

  }

  if (i == 0 && e == 0)

    return 0.0;  /* invalid format (no digit) */

  e *= -4;  /* each fractional digit divides value by 2^-4 */

  *endptr = cast(char *, s);  /* valid up to here */

  if (*s == 'p' || *s == 'P') {  /* exponent part? */

    int exp1 = 0;

    int neg1;

    s++;  /* skip 'p' */

    neg1 = isneg(&s);  /* signal */

    if (!lisdigit(cast_uchar(*s)))

      goto ret;  /* must have at least one digit */

    while (lisdigit(cast_uchar(*s)))  /* read exponent */

      exp1 = exp1 * 10 + *(s++) - '0';

    if (neg1) exp1 = -exp1;

    e += exp1;

  }

  *endptr = cast(char *, s);  /* valid up to here */

 ret:

  if (neg) r = -r;

  return ldexp(r, e);

}

#endif

int luaO_str2d (const char *s, size_t len, lua_Number *result) {

  char *endptr;

  if (strpbrk(s, "nN"))  /* reject 'inf' and 'nan' */

    return 0;

  else if (strpbrk(s, "xX"))  /* hexa? */

    *result = lua_strx2number(s, &endptr);

  else

    *result = lua_str2number(s, &endptr);

  if (endptr == s) return 0;  /* nothing recognized */

  while (lisspace(cast_uchar(*endptr))) endptr++;

  return (endptr == s + len);  /* OK if no trailing characters */

}

static void pushstr (lua_State *L, const char *str, size_t l) {

  setsvalue2s(L, L->top, luaS_newlstr(L, str, l));

  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 = 0;

  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, strlen(s));

        break;

      }

      case 'c': {

        char buff;

        buff = cast(char, va_arg(argp, int));

        pushstr(L, &buff, 1);

        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' */

        int l = sprintf(buff, "%p", va_arg(argp, void *));

        pushstr(L, buff, l);

        break;

      }

      case '%': {

        pushstr(L, "%", 1);

        break;

      }

      default: {

        luaG_runerror(L,

            "invalid option " LUA_QL("%%%c") " to " LUA_QL("lua_pushfstring"),

            *(e + 1));

      }

    }

    n += 2;

    fmt = e+2;

  }

  pushstr(L, fmt, strlen(fmt));

  if (n > 0) luaV_concat(L, n + 1);

  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;

}

/* number of chars of a literal string without the ending \0 */

#define LL(x)	(sizeof(x)/sizeof(char) - 1)

#define RETS	"..."

#define PRE	"[string \""

#define POS	"\"]"

#define addstr(a,b,l)	( memcpy(a,b,(l) * sizeof(char)), a += (l) )

void luaO_chunkid (char *out, const char *source, size_t bufflen) {

  size_t l = strlen(source);

  if (*source == '=') {  /* 'literal' source */

    if (l <= bufflen)  /* small enough? */

      memcpy(out, source + 1, l * sizeof(char));

    else {  /* truncate it */

      addstr(out, source + 1, bufflen - 1);

      *out = '\0';

    }

  }

  else if (*source == '@') {  /* file name */

    if (l <= bufflen)  /* small enough? */

      memcpy(out, source + 1, l * sizeof(char));

    else {  /* add '...' before rest of name */

      addstr(out, RETS, LL(RETS));

      bufflen -= LL(RETS);

      memcpy(out, source + 1 + l - bufflen, bufflen * sizeof(char));

    }

  }

  else {  /* string; format as [string "source"] */

    const char *nl = strchr(source, '\n');  /* find first new line (if any) */

    addstr(out, PRE, LL(PRE));  /* add prefix */

    bufflen -= LL(PRE RETS POS) + 1;  /* save space for prefix+suffix+'\0' */

    if (l < bufflen && nl == NULL) {  /* small one-line source? */

      addstr(out, source, l);  /* keep it */

    }

    else {

      if (nl != NULL) l = nl - source;  /* stop at first newline */

      if (l > bufflen) l = bufflen;

      addstr(out, source, l);

      addstr(out, RETS, LL(RETS));

    }

    memcpy(out, POS, (LL(POS) + 1) * sizeof(char));

  }

}