kolibrios/programs/develop/open watcom/trunk/clib/convert/strtoll.c
Sergey Semyonov (Serge) 43bd1e645f Clib char & math functions
git-svn-id: svn://kolibrios.org@554 a494cfbc-eb01-0410-851d-a64ba20cac60
2007-06-26 11:19:49 +00:00

178 lines
5.8 KiB
C

/****************************************************************************
*
* Open Watcom Project
*
* Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
*
* ========================================================================
*
* This file contains Original Code and/or Modifications of Original
* Code as defined in and that are subject to the Sybase Open Watcom
* Public License version 1.0 (the 'License'). You may not use this file
* except in compliance with the License. BY USING THIS FILE YOU AGREE TO
* ALL TERMS AND CONDITIONS OF THE LICENSE. A copy of the License is
* provided with the Original Code and Modifications, and is also
* available at www.sybase.com/developer/opensource.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND SYBASE AND ALL CONTRIBUTORS HEREBY DISCLAIM
* ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR
* NON-INFRINGEMENT. Please see the License for the specific language
* governing rights and limitations under the License.
*
* ========================================================================
*
* Description: String to long long conversion routines.
*
****************************************************************************/
#include "variety.h"
#include "widechar.h"
#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#ifdef __WIDECHAR__
#include <wctype.h>
#else
#include <ctype.h>
#endif
#include <errno.h>
#include <limits.h>
#include "seterrno.h"
/* This is heavily based on strtol() implementation; however this code needs
* to use 64-bit arithmetic and there is little need to drag in all the
* supporting code for people who just need 16- or 32-bit string to integer
* conversion.
*/
/*
* this table is the largest value that can safely be multiplied
* by the associated base without overflowing
*/
static unsigned long long nearly_overflowing[] = {
ULLONG_MAX / 2, ULLONG_MAX / 3, ULLONG_MAX / 4, ULLONG_MAX / 5,
ULLONG_MAX / 6, ULLONG_MAX / 7, ULLONG_MAX / 8, ULLONG_MAX / 9,
ULLONG_MAX / 10, ULLONG_MAX / 11, ULLONG_MAX / 12, ULLONG_MAX / 13,
ULLONG_MAX / 14, ULLONG_MAX / 15, ULLONG_MAX / 16, ULLONG_MAX / 17,
ULLONG_MAX / 18, ULLONG_MAX / 19, ULLONG_MAX / 20, ULLONG_MAX / 21,
ULLONG_MAX / 22, ULLONG_MAX / 23, ULLONG_MAX / 24, ULLONG_MAX / 25,
ULLONG_MAX / 26, ULLONG_MAX / 27, ULLONG_MAX / 28, ULLONG_MAX / 29,
ULLONG_MAX / 30, ULLONG_MAX / 31, ULLONG_MAX / 32, ULLONG_MAX / 33,
ULLONG_MAX / 34, ULLONG_MAX / 35, ULLONG_MAX / 36
};
static int radix_value( CHAR_TYPE c )
{
if( c >= '0' && c <= '9' ) return( c - '0' );
c = __F_NAME(tolower,towlower)(c);
if( c >= 'a' && c <= 'i' ) return( c - 'a' + 10 );
if( c >= 'j' && c <= 'r' ) return( c - 'j' + 19 );
if( c >= 's' && c <= 'z' ) return( c - 's' + 28 );
return( 37 );
}
#define hexstr(p) (p[0] == '0' && (p[1] == 'x' || p[1] == 'X'))
static unsigned long long int _stoll( const CHAR_TYPE *nptr, CHAR_TYPE **endptr, int base, int who )
{
const CHAR_TYPE *p;
const CHAR_TYPE *startp;
int digit;
unsigned long long int value;
unsigned long long int prev_value;
CHAR_TYPE sign;
char overflow; /*overflow is used as a flag so it does not
*need to be of type CHAR_TYPE */
if( endptr != NULL )
*endptr = (CHAR_TYPE *)nptr;
p = nptr;
while( __F_NAME(isspace,iswspace)(*p) )
++p;
sign = *p;
if( sign == '+' || sign == '-' )
++p;
if( base == 0 ) {
if( hexstr(p) )
base = 16;
else if( *p == '0' )
base = 8;
else
base = 10;
}
if( base < 2 || base > 36 ) {
__set_errno( EDOM );
return( 0 );
}
if( base == 16 ) {
if( hexstr(p) )
p += 2; /* skip over '0x' */
}
startp = p;
overflow = 0;
value = 0;
for(;;) {
digit = radix_value( *p );
if( digit >= base )
break;
if( value > nearly_overflowing[base-2] )
overflow = 1;
prev_value = value;
value = value * base + digit;
if( value < prev_value )
overflow = 1;
++p;
}
if( p == startp )
p = nptr;
if( endptr != NULL )
*endptr = (CHAR_TYPE *)p;
if( who == 1 ) {
if( value >= 0x8000000000000000 ) {
if( value == 0x8000000000000000 && sign == '-' ) {
; /* OK */
} else {
overflow = 1;
}
}
}
if( overflow ) {
__set_errno( ERANGE );
if( who == 0 )
return( ULLONG_MAX );
if( sign == '-' )
return( LLONG_MIN );
return( LLONG_MAX );
}
if( sign == '-' )
value = - value;
return( value );
}
_WCRTLINK unsigned long long int __F_NAME(strtoull,wcstoull)( const CHAR_TYPE *nptr, CHAR_TYPE **endptr, int base )
{
return( _stoll( nptr, endptr, base, 0 ) );
}
_WCRTLINK long long int __F_NAME(strtoll,wcstoll)( const CHAR_TYPE *nptr, CHAR_TYPE **endptr, int base )
{
return( _stoll( nptr, endptr, base, 1 ) );
}
/* Assuming that intmax_t is equal to long long and uintmax_t to unsigned long long */
_WCRTLINK uintmax_t __F_NAME(strtoumax,wcstoumax)( const CHAR_TYPE *nptr, CHAR_TYPE **endptr, int base )
{
return( _stoll( nptr, endptr, base, 0 ) );
}
_WCRTLINK intmax_t __F_NAME(strtoimax,wcstoimax)( const CHAR_TYPE *nptr, CHAR_TYPE **endptr, int base )
{
return( _stoll( nptr, endptr, base, 1 ) );
}