mariadb/strings/my_strtoll10.c
Alexander Barkov 9ac8172ac3 MDEV-31221 UBSAN runtime error: negation of -9223372036854775808 cannot be represented in type 'long long int' in my_strtoll10_utf32
The code in my_strtoll10_mb2 and my_strtoll10_utf32
could hit undefinite behavior by negation of LONGLONG_MIN.
Fixing to avoid this.

Also, fixing my_strtoll10() in the same style.
The previous reduction produced a redundant warning on
CAST(_latin1'-9223372036854775808' AS SIGNED)
2024-09-20 13:04:57 +04:00

257 lines
6.8 KiB
C

/* Copyright (c) 2003 TXT DataKonsult Ab
Copyright (c) 2009, 2013, Monty Program Ab.
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 the following disclaimer in
the documentation and/or other materials provided with the
distribution.
THIS SOFTWARE IS PROVIDED BY <COPYRIGHT HOLDER> ``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 <COPYRIGHT HOLDER> 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 "strings_def.h"
#include <my_sys.h> /* Needed for MY_ERRNO_ERANGE */
#define MAX_NEGATIVE_NUMBER ((ulonglong) 0x8000000000000000ULL)
#define INIT_CNT 9
#define LFACTOR 1000000000ULL
#define LFACTOR1 10000000000ULL
#define LFACTOR2 100000000000ULL
static unsigned long lfactor[9]=
{
1L, 10L, 100L, 1000L, 10000L, 100000L, 1000000L, 10000000L, 100000000L
};
/*
Convert a string to an to unsigned long long integer value
SYNOPSIS
my_strtoll10()
nptr in pointer to the string to be converted
endptr in/out pointer to the end of the string/
pointer to the stop character
error out returned error code
DESCRIPTION
This function takes the decimal representation of integer number
from string nptr and converts it to an signed or unsigned
long long integer value.
Space characters and tab are ignored.
A sign character might precede the digit characters. The number
may have any number of pre-zero digits.
The function stops reading the string nptr at the first character
that is not a decimal digit. If endptr is not NULL then the function
will not read characters after *endptr.
RETURN VALUES
Value of string as a signed/unsigned longlong integer
if no error and endptr != NULL, it will be set to point at the character
after the number
The error parameter contains information how things went:
-1 Number was an ok negative number
0 ok
ERANGE If the the value of the converted number exceeded the
maximum negative/unsigned long long integer.
In this case the return value is ~0 if value was
positive and LONGLONG_MIN if value was negative.
EDOM If the string didn't contain any digits. In this case
the return value is 0.
If endptr is not NULL the function will store the end pointer to
the stop character here.
*/
longlong my_strtoll10(const char *nptr, char **endptr, int *error)
{
const char *s, *end, *start, *n_end, *true_end;
char *dummy;
uchar c;
unsigned long i, j, k;
ulonglong li;
int negative;
ulong cutoff, cutoff2, cutoff3;
s= nptr;
/* If fixed length string */
if (endptr)
{
end= *endptr;
/* Skip leading spaces */
for ( ; s < end && my_isspace(&my_charset_latin1, *s) ; )
s++;
if (s == end)
goto no_conv;
}
else
{
endptr= &dummy; /* Easier end test */
/* Skip leading spaces */
for ( ; ; s++)
{
if (!*s)
goto no_conv;
if (!my_isspace(&my_charset_latin1, *s))
break;
}
/* This number must be big to guard against a lot of pre-zeros */
end= s+65535; /* Can't be longer than this */
}
/* Check for a sign. */
negative= 0;
if (*s == '-')
{
*error= -1; /* Mark as negative number */
negative= 1;
if (++s == end)
goto no_conv;
cutoff= MAX_NEGATIVE_NUMBER / LFACTOR2;
cutoff2= (MAX_NEGATIVE_NUMBER % LFACTOR2) / 100;
cutoff3= MAX_NEGATIVE_NUMBER % 100;
}
else
{
*error= 0;
if (*s == '+')
{
if (++s == end)
goto no_conv;
}
cutoff= ULONGLONG_MAX / LFACTOR2;
cutoff2= ULONGLONG_MAX % LFACTOR2 / 100;
cutoff3= ULONGLONG_MAX % 100;
}
/* Handle case where we have a lot of pre-zero */
if (*s == '0')
{
i= 0;
do
{
if (++s == end)
goto end_i; /* Return 0 */
}
while (*s == '0');
n_end= s+ INIT_CNT;
}
else
{
/* Read first digit to check that it's a valid number */
if ((c= (*s-'0')) > 9)
goto no_conv;
i= c;
n_end= ++s+ INIT_CNT-1;
}
/* Handle first 9 digits and store them in i */
if (n_end > end)
n_end= end;
for (; s != n_end ; s++)
{
if ((c= (*s-'0')) > 9)
goto end_i;
i= i*10+c;
}
if (s == end)
goto end_i;
/* Handle next 9 digits and store them in j */
j= 0;
start= s; /* Used to know how much to shift i */
n_end= true_end= s + INIT_CNT;
if (n_end > end)
n_end= end;
do
{
if ((c= (*s-'0')) > 9)
goto end_i_and_j;
j= j*10+c;
} while (++s != n_end);
if (s == end)
{
if (s != true_end)
goto end_i_and_j;
goto end3;
}
if ((c= (*s-'0')) > 9)
goto end3;
/* Handle the next 1 or 2 digits and store them in k */
k=c;
if (++s == end || (c= (*s-'0')) > 9)
goto end4;
k= k*10+c;
*endptr= (char*) ++s;
/* number string should have ended here */
if (s != end && (c= (*s-'0')) <= 9)
goto overflow;
/* Check that we didn't get an overflow with the last digit */
if (i > cutoff || (i == cutoff && (j > cutoff2 || (j == cutoff2 &&
k > cutoff3))))
goto overflow;
li=i*LFACTOR2+ (ulonglong) j*100 + k;
return (longlong) li;
overflow: /* *endptr is set here */
*error= MY_ERRNO_ERANGE;
return negative ? LONGLONG_MIN : (longlong) ULONGLONG_MAX;
end_i:
*endptr= (char*) s;
return (negative ? ((longlong) -(long) i) : (longlong) i);
end_i_and_j:
li= (ulonglong) i * lfactor[(uint) (s-start)] + j;
*endptr= (char*) s;
return (negative ? -((longlong) li) : (longlong) li);
end3:
li=(ulonglong) i*LFACTOR+ (ulonglong) j;
*endptr= (char*) s;
return (negative ? -((longlong) li) : (longlong) li);
end4:
li=(ulonglong) i*LFACTOR1+ (ulonglong) j * 10 + k;
*endptr= (char*) s;
if (negative)
{
if (li > MAX_NEGATIVE_NUMBER)
goto overflow;
if (li == MAX_NEGATIVE_NUMBER) // Avoid undefined behavior
return LONGLONG_MIN;
return -((longlong) li);
}
return (longlong) li;
no_conv:
/* There was no number to convert. */
*error= MY_ERRNO_EDOM;
*endptr= (char *) nptr;
return 0;
}