busybox/libbb/bb_strtonum.c

148 lines
3.7 KiB
C
Raw Normal View History

2006-11-27 20:42:16 +05:30
/* vi: set sw=4 ts=4: */
/*
* Utility routines.
*
* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
#include "libbb.h"
/* On exit: errno = 0 only if there was non-empty, '\0' terminated value
* errno = EINVAL if value was not '\0' terminated, but othervise ok
* Return value is still valid, caller should just check whether end[0]
* is a valid terminating char for particular case. OTOH, if caller
* requires '\0' terminated input, [s]he can just check errno == 0.
* errno = ERANGE if value had alphanumeric terminating char ("1234abcg").
* errno = ERANGE if value is out of range, missing, etc.
* errno = ERANGE if value had minus sign for strtouXX (even "-0" is not ok )
*/
static unsigned long long ret_ERANGE(void)
{
errno = ERANGE; /* this ain't as small as it looks (on glibc) */
return ULLONG_MAX;
}
static unsigned long long handle_errors(unsigned long long v, char **endp, char *endptr)
{
if (endp) *endp = endptr;
/* Check for the weird "feature":
* a "-" string is apparently a valid "number" for strto[u]l[l]!
* It returns zero and errno is 0! :( */
if (endptr[-1] == '-')
return ret_ERANGE();
/* errno is already set to ERANGE by strtoXXX if value overflowed */
if (endptr[0]) {
/* "1234abcg" or out-of-range? */
if (isalnum(endptr[0]) || errno)
return ret_ERANGE();
/* good number, just suspicious terminator */
errno = EINVAL;
}
return v;
}
unsigned long long bb_strtoull(const char *arg, char **endp, int base)
{
char *endptr;
/* strtoul(" -4200000000") returns 94967296, errno 0 (!) */
/* I don't think that this is right. Preventing this... */
if (!isalnum(arg[0])) return ret_ERANGE();
/* not 100% correct for lib func, but convenient for the caller */
errno = 0;
return handle_errors(strtoull(arg, &endptr, base), endp, endptr);
}
long long bb_strtoll(const char *arg, char **endp, int base)
{
char *endptr;
if (arg[0] != '-' && !isalnum(arg[0])) return ret_ERANGE();
errno = 0;
return handle_errors(strtoll(arg, &endptr, base), endp, endptr);
}
#if ULONG_MAX != ULLONG_MAX
unsigned long bb_strtoul(const char *arg, char **endp, int base)
{
char *endptr;
if (!isalnum(arg[0])) return ret_ERANGE();
errno = 0;
return handle_errors(strtoul(arg, &endptr, base), endp, endptr);
}
long bb_strtol(const char *arg, char **endp, int base)
{
char *endptr;
if (arg[0] != '-' && !isalnum(arg[0])) return ret_ERANGE();
errno = 0;
return handle_errors(strtol(arg, &endptr, base), endp, endptr);
}
#endif
#if UINT_MAX != ULONG_MAX
unsigned bb_strtou(const char *arg, char **endp, int base)
{
unsigned long v;
char *endptr;
if (!isalnum(arg[0])) return ret_ERANGE();
errno = 0;
v = strtoul(arg, &endptr, base);
if (v > UINT_MAX) return ret_ERANGE();
return handle_errors(v, endp, endptr);
}
int bb_strtoi(const char *arg, char **endp, int base)
{
long v;
char *endptr;
if (arg[0] != '-' && !isalnum(arg[0])) return ret_ERANGE();
errno = 0;
v = strtol(arg, &endptr, base);
if (v > INT_MAX) return ret_ERANGE();
if (v < INT_MIN) return ret_ERANGE();
return handle_errors(v, endp, endptr);
}
#endif
/* Floating point */
#if 0
#include <math.h> /* just for HUGE_VAL */
#define NOT_DIGIT(a) (((unsigned char)(a-'0')) > 9)
double bb_strtod(const char *arg, char **endp)
{
double v;
char *endptr;
if (arg[0] != '-' && NOT_DIGIT(arg[0])) goto err;
errno = 0;
v = strtod(arg, &endptr);
if (endp) *endp = endptr;
if (endptr[0]) {
/* "1234abcg" or out-of-range? */
if (isalnum(endptr[0]) || errno) {
err:
errno = ERANGE;
return HUGE_VAL;
}
/* good number, just suspicious terminator */
errno = EINVAL;
}
return v;
}
#endif