/* $NetBSD: strtoimax.c,v 1.4 2005/11/29 03:12:00 christos Exp $ */ | |
/*- | |
* Copyright (c) 1992, 1993 | |
* The Regents of the University of California. All rights reserved. | |
* | |
* Redistribution and use in source and binary forms, with or without | |
* modification, are permitted provided that the following conditions | |
* are met: | |
* 1. Redistributions of source code must retain the above copyright | |
* notice, this list of conditions and the following disclaimer. | |
* 2. Redistributions in binary form must reproduce the above copyright | |
* notice, this list of conditions and the following disclaimer in the | |
* documentation and/or other materials provided with the distribution. | |
* 3. Neither the name of the University nor the names of its contributors | |
* may be used to endorse or promote products derived from this software | |
* without specific prior written permission. | |
* | |
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND | |
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE | |
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
* SUCH DAMAGE. | |
*/ | |
#include <LibConfig.h> | |
#include <sys/EfiCdefs.h> | |
#if defined(LIBC_SCCS) && !defined(lint) | |
#if 0 | |
static char sccsid[] = "from: @(#)strtoq.c 8.1 (Berkeley) 6/4/93"; | |
#else | |
__RCSID("$NetBSD: strtoimax.c,v 1.4 2005/11/29 03:12:00 christos Exp $"); | |
#endif | |
#endif /* LIBC_SCCS and not lint */ | |
#include "namespace.h" | |
#include <assert.h> | |
#include <ctype.h> | |
#include <errno.h> | |
#include <inttypes.h> | |
#include <stddef.h> | |
#ifdef __weak_alias | |
__weak_alias(strtoimax, _strtoimax) | |
#endif | |
/* | |
* Convert a string to an intmax_t. | |
* | |
* Ignores `locale' stuff. Assumes that the upper and lower case | |
* alphabets and digits are each contiguous. | |
*/ | |
intmax_t | |
_strtoimax(const char *nptr, char **endptr, int base) | |
{ | |
const char *s; | |
intmax_t acc, cutoff; | |
int c; | |
int neg, any, cutlim; | |
_DIAGASSERT(nptr != NULL); | |
/* endptr may be NULL */ | |
#ifdef __GNUC__ | |
/* This outrageous construct just to shut up a GCC warning. */ | |
(void) &acc; (void) &cutoff; | |
#endif | |
/* | |
* Skip white space and pick up leading +/- sign if any. | |
* If base is 0, allow 0x for hex and 0 for octal, else | |
* assume decimal; if base is already 16, allow 0x. | |
*/ | |
s = nptr; | |
do { | |
c = (unsigned char) *s++; | |
} while (isspace(c)); | |
if (c == '-') { | |
neg = 1; | |
c = *s++; | |
} else { | |
neg = 0; | |
if (c == '+') | |
c = *s++; | |
} | |
if ((base == 0 || base == 16) && | |
c == '0' && (*s == 'x' || *s == 'X')) { | |
c = s[1]; | |
s += 2; | |
base = 16; | |
} | |
if (base == 0) | |
base = c == '0' ? 8 : 10; | |
/* | |
* Compute the cutoff value between legal numbers and illegal | |
* numbers. That is the largest legal value, divided by the | |
* base. An input number that is greater than this value, if | |
* followed by a legal input character, is too big. One that | |
* is equal to this value may be valid or not; the limit | |
* between valid and invalid numbers is then based on the last | |
* digit. For instance, if the range for intmax_t is | |
* [-9223372036854775808..9223372036854775807] and the input base | |
* is 10, cutoff will be set to 922337203685477580 and cutlim to | |
* either 7 (neg==0) or 8 (neg==1), meaning that if we have | |
* accumulated a value > 922337203685477580, or equal but the | |
* next digit is > 7 (or 8), the number is too big, and we will | |
* return a range error. | |
* | |
* Set any if any `digits' consumed; make it negative to indicate | |
* overflow. | |
*/ | |
cutoff = neg ? INTMAX_MIN : INTMAX_MAX; | |
cutlim = (int)(cutoff % base); | |
cutoff /= base; | |
if (neg) { | |
if (cutlim > 0) { | |
cutlim -= base; | |
cutoff += 1; | |
} | |
cutlim = -cutlim; | |
} | |
for (acc = 0, any = 0;; c = (unsigned char) *s++) { | |
if (isdigit(c)) | |
c -= '0'; | |
else if (isalpha(c)) | |
c -= isupper(c) ? 'A' - 10 : 'a' - 10; | |
else | |
break; | |
if (c >= base) | |
break; | |
if (any < 0) | |
continue; | |
if (neg) { | |
if (acc < cutoff || (acc == cutoff && c > cutlim)) { | |
any = -1; | |
acc = INTMAX_MIN; | |
errno = ERANGE; | |
} else { | |
any = 1; | |
acc *= base; | |
acc -= c; | |
} | |
} else { | |
if (acc > cutoff || (acc == cutoff && c > cutlim)) { | |
any = -1; | |
acc = INTMAX_MAX; | |
errno = ERANGE; | |
} else { | |
any = 1; | |
acc *= base; | |
acc += c; | |
} | |
} | |
} | |
if (endptr != 0) | |
*endptr = (char *)(any ? s - 1 : nptr); | |
//*endptr = __UNCONST(any ? s - 1 : nptr); | |
return (acc); | |
} |