Attempt to return proper overflow/underflow messages for platforms that

only return Nan and set errno for pow/exp overflow/underflow.
This commit is contained in:
Bruce Momjian 2007-01-03 14:35:24 +00:00
parent ada6fd63d9
commit 990fea847f
1 changed files with 23 additions and 6 deletions

View File

@ -8,7 +8,7 @@
* *
* *
* IDENTIFICATION * IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/utils/adt/float.c,v 1.136 2007/01/03 04:21:47 momjian Exp $ * $PostgreSQL: pgsql/src/backend/utils/adt/float.c,v 1.137 2007/01/03 14:35:24 momjian Exp $
* *
*------------------------------------------------------------------------- *-------------------------------------------------------------------------
*/ */
@ -1440,11 +1440,19 @@ dpow(PG_FUNCTION_ARGS)
/* /*
* pow() sets errno only on some platforms, depending on whether it * pow() sets errno only on some platforms, depending on whether it
* follows _IEEE_, _POSIX_, _XOPEN_, or _SVID_, so, for consistency, * follows _IEEE_, _POSIX_, _XOPEN_, or _SVID_, and some return Nan,
* we don't consult it and just do our check below. * so we check and set result properly.
*/ */
errno = 0;
result = pow(arg1, arg2); result = pow(arg1, arg2);
if (errno == ERANGE && isnan(result))
{
if ((fabs(arg1) > 1 && arg2 >= 0) || (fabs(arg1) < 1 && arg2 < 0))
result = (arg1 >= 0) ? get_float8_infinity() : -get_float8_infinity();
else
result = 0;
}
CHECKFLOATVAL(result, isinf(arg1) || isinf(arg2), arg1 == 0); CHECKFLOATVAL(result, isinf(arg1) || isinf(arg2), arg1 == 0);
PG_RETURN_FLOAT8(result); PG_RETURN_FLOAT8(result);
} }
@ -1461,10 +1469,19 @@ dexp(PG_FUNCTION_ARGS)
/* /*
* exp() sets errno only on some platforms, depending on whether it * exp() sets errno only on some platforms, depending on whether it
* follows _IEEE_, _POSIX_, _XOPEN_, or _SVID_, so, for consistency, * follows _IEEE_, _POSIX_, _XOPEN_, or _SVID_, and some return Nan,
* we don't consult it and just do our check below. * so we check and set result properly.
*/ */
errno = 0;
result = exp(arg1); result = exp(arg1);
if (errno == ERANGE && isnan(result))
{
if (arg1 >= 0)
result = get_float8_infinity();
else
result = 0;
}
CHECKFLOATVAL(result, isinf(arg1), false); CHECKFLOATVAL(result, isinf(arg1), false);
PG_RETURN_FLOAT8(result); PG_RETURN_FLOAT8(result);