hush/libbb/bb_strtonum.c
Denys Vlasenko ba65872950 libbb/bb_strtonum: always set end ptr, even on error return
function                                             old     new   delta
handle_errors                                         69      61      -8

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2011-12-22 13:00:32 +01:00

161 lines
4.0 KiB
C

/* 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 source tree.
*/
#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 otherwise 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 )
* return value is all-ones in this case.
*
* Test code:
* char *endptr;
* const char *minus = "-";
* errno = 0;
* bb_strtoi(minus, &endptr, 0); // must set ERANGE
* printf("minus:%p endptr:%p errno:%d EINVAL:%d\n", minus, endptr, errno, EINVAL);
* errno = 0;
* bb_strtoi("-0-", &endptr, 0); // must set EINVAL and point to second '-'
* printf("endptr[0]:%c errno:%d EINVAL:%d\n", endptr[0], errno, EINVAL);
*/
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 next_ch = **endp;
/* errno is already set to ERANGE by strtoXXX if value overflowed */
if (next_ch) {
/* "1234abcg" or out-of-range? */
if (isalnum(next_ch) || errno)
return ret_ERANGE();
/* good number, just suspicious terminator */
errno = EINVAL;
}
return v;
}
unsigned long long FAST_FUNC bb_strtoull(const char *arg, char **endp, int base)
{
unsigned long long v;
char *endptr;
if (!endp) endp = &endptr;
*endp = (char*) arg;
/* 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;
v = strtoull(arg, endp, base);
return handle_errors(v, endp);
}
long long FAST_FUNC bb_strtoll(const char *arg, char **endp, int base)
{
unsigned long long v;
char *endptr;
char first;
if (!endp) endp = &endptr;
*endp = (char*) arg;
/* Check for the weird "feature":
* a "-" string is apparently a valid "number" for strto[u]l[l]!
* It returns zero and errno is 0! :( */
first = (arg[0] != '-' ? arg[0] : arg[1]);
if (!isalnum(first)) return ret_ERANGE();
errno = 0;
v = strtoll(arg, endp, base);
return handle_errors(v, endp);
}
#if ULONG_MAX != ULLONG_MAX
unsigned long FAST_FUNC bb_strtoul(const char *arg, char **endp, int base)
{
unsigned long v;
char *endptr;
if (!endp) endp = &endptr;
*endp = (char*) arg;
if (!isalnum(arg[0])) return ret_ERANGE();
errno = 0;
v = strtoul(arg, endp, base);
return handle_errors(v, endp);
}
long FAST_FUNC bb_strtol(const char *arg, char **endp, int base)
{
long v;
char *endptr;
char first;
if (!endp) endp = &endptr;
*endp = (char*) arg;
first = (arg[0] != '-' ? arg[0] : arg[1]);
if (!isalnum(first)) return ret_ERANGE();
errno = 0;
v = strtol(arg, endp, base);
return handle_errors(v, endp);
}
#endif
#if UINT_MAX != ULONG_MAX
unsigned FAST_FUNC bb_strtou(const char *arg, char **endp, int base)
{
unsigned long v;
char *endptr;
if (!endp) endp = &endptr;
*endp = (char*) arg;
if (!isalnum(arg[0])) return ret_ERANGE();
errno = 0;
v = strtoul(arg, endp, base);
if (v > UINT_MAX) return ret_ERANGE();
return handle_errors(v, endp);
}
int FAST_FUNC bb_strtoi(const char *arg, char **endp, int base)
{
long v;
char *endptr;
char first;
if (!endp) endp = &endptr;
*endp = (char*) arg;
first = (arg[0] != '-' ? arg[0] : arg[1]);
if (!isalnum(first)) return ret_ERANGE();
errno = 0;
v = strtol(arg, endp, base);
if (v > INT_MAX) return ret_ERANGE();
if (v < INT_MIN) return ret_ERANGE();
return handle_errors(v, endp);
}
#endif