| lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 1 | /* |
| 2 | * ==================================================== |
| 3 | * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
| 4 | * |
| 5 | * Developed at SunPro, a Sun Microsystems, Inc. business. |
| 6 | * Permission to use, copy, modify, and distribute this |
| 7 | * software is freely granted, provided that this notice |
| 8 | * is preserved. |
| 9 | * ==================================================== |
| 10 | */ |
| 11 | |
| 12 | #include "math.h" |
| 13 | #include "math_private.h" |
| 14 | #include <errno.h> |
| 15 | |
| 16 | /* TODO: POSIX says: |
| 17 | * |
| 18 | * "If the integer expression (math_errhandling & MATH_ERRNO) is non-zero, |
| 19 | * then errno shall be set to [ERANGE]. If the integer expression |
| 20 | * (math_errhandling & MATH_ERREXCEPT) is non-zero, then the underflow |
| 21 | * floating-point exception shall be raised." |
| 22 | * |
| 23 | * *And it says the same about scalbn*! Thus these two functions |
| 24 | * are the same and can be just aliased. |
| 25 | * |
| 26 | * Currently, ldexp tries to be vaguely POSIX compliant while scalbn |
| 27 | * does not (it does not set ERRNO). |
| 28 | */ |
| 29 | |
| 30 | double ldexp(double value, int _exp) |
| 31 | { |
| 32 | if (!isfinite(value) || value == 0.0) |
| 33 | return value; |
| 34 | value = scalbn(value, _exp); |
| 35 | if (!isfinite(value) || value == 0.0) |
| 36 | errno = ERANGE; |
| 37 | return value; |
| 38 | } |
| 39 | libm_hidden_def(ldexp) |