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 */
}
/*
** 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; /* result (accumulator) */
int sigdig = 0; /* number of significant digits */
int nosigdig = 0; /* number of non-significant digits */
int e = 0; /* exponent correction */
int neg = 0; /* 1 if number is negative */
int dot = 0; /* true after seen a dot */
*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') */
for (s += 2; ; s++) { /* skip '0x' and read numeral */
if (*s == '.') {
if (dot) break; /* second dot? stop loop */
else dot = 1;
}
else if (lisxdigit(cast_uchar(*s))) {
if (sigdig == 0 && *s == '0') { /* non-significant zero? */
nosigdig++;
if (dot) e--; /* zero after dot? correct exponent */
}
else {
if (++sigdig <= MAXSIGDIG) { /* can read it without overflow? */
r = (r * cast_num(16.0)) + luaO_hexavalue(cast_uchar(*s));
if (dot) e--; /* decimal digit */
}
else /* too many digits; ignore */
if (!dot) e++; /* still count it for exponent */
}
}
else break; /* neither a dot nor a digit */
}
if (nosigdig + sigdig == 0) /* no digits? */
return 0.0; /* invalid format */
*endptr = cast(char *, s); /* valid up to here */
e *= 4; /* each digit multiplies/divides value by 2^4 */
if (*s == 'p' || *s == 'P') { /* exponent part? */
int exp1 = 0; /* exponent value */
int neg1; /* exponent signal */
s++; /* skip 'p' */
neg1 = isneg(&s); /* signal */
if (!lisdigit(cast_uchar(*s)))
return 0.0; /* invalid; 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 */
}
static lua_Number lua_strb2number (const char *s, char **endptr) {
lua_Number r = 0.0;
int i = 0; int f = 0;
*endptr = cast(char *, s); /* nothing is valid yet */
while (lisspace(cast_uchar(*s))) s++; /* skip initial spaces */
if (!(*s == '0' && (*(s + 1) == 'b' || *(s + 1) == 'B'))) /* check '0b' */
return 0.0; /* invalid format (no '0b') */
s += 2; /* skip '0b' */
while ((*s == '0') || (*s == '1'))
{
f = 0;
r *= 2.0;
if (*s == '1') r += 1.0;
i++; s++;
while (*s == '_') {s++; f = 1;}
}
if ((i == 0) || (f > 0))
return 0.0; /* invalid format */
*endptr = cast(char *, s); /* valid up to here */
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 l_mathop(ldexp)(r, e);
}
static void read_string (LexState *ls, int del, SemInfo *seminfo) {
save_and_next(ls); /* keep delimiter (for error messages) */
while (ls->current != del) {
switch (ls->current) {
case EOZ:
lexerror(ls, "unfinished string", TK_EOS);
break; /* to avoid warnings */
case '\n':
case '\r':
lexerror(ls, "unfinished string", TK_STRING);
break; /* to avoid warnings */
case '\\': { /* escape sequences */
int c; /* final character to be saved */
save_and_next(ls); /* keep '\\' for error messages */
switch (ls->current) {
case 'a': c = '\a'; goto read_save;
case 'b': c = '\b'; goto read_save;
case 'f': c = '\f'; goto read_save;
case 'n': c = '\n'; goto read_save;
case 'r': c = '\r'; goto read_save;
case 't': c = '\t'; goto read_save;
case 'v': c = '\v'; goto read_save;
case 'x': c = readhexaesc(ls); goto read_save;
case 'u': utf8esc(ls); goto no_save;
case '\n': case '\r':
inclinenumber(ls); c = '\n'; goto only_save;
case '\\': case '\"': case '\'':
c = ls->current; goto read_save;
case EOZ: goto no_save; /* will raise an error next loop */
case 'z': { /* zap following span of spaces */
luaZ_buffremove(ls->buff, 1); /* remove '\\' */
next(ls); /* skip the 'z' */
while (lisspace(ls->current)) {
if (currIsNewline(ls)) inclinenumber(ls);
else next(ls);
}
goto no_save;
}
default: {
esccheck(ls, lisdigit(ls->current), "invalid escape sequence");
c = readdecesc(ls); /* digital escape '\ddd' */
goto only_save;
}
}
read_save:
next(ls);
/* go through */
only_save:
luaZ_buffremove(ls->buff, 1); /* remove '\\' */
save(ls, c);
/* go through */
no_save: break;
}
default:
save_and_next(ls);
}
}
save_and_next(ls); /* skip delimiter */
seminfo->ts = luaX_newstring(ls, luaZ_buffer(ls->buff) + 1,
luaZ_bufflen(ls->buff) - 2);
}
