glibc/misc/qefgcvt.c

46 lines
1.8 KiB
C

/* Compatibility functions for floating point formatting, long double version.
Copyright (C) 1996, 1997, 1999, 2000 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <float.h>
#define FLOAT_TYPE long double
#define FUNC_PREFIX q
#define FLOAT_FMT_FLAG "L"
/* Actually we have to write (LDBL_DIG + log10 (LDBL_MAX_10_EXP)) but
we don't have log10 available in the preprocessor. Since we cannot
assume anything on the used `long double' format be generous. */
#define MAXDIG (NDIGIT_MAX + 12)
#define FCVT_MAXDIG (LDBL_MAX_10_EXP + MAXDIG)
#if LDBL_MANT_DIG == 64
# define NDIGIT_MAX 21
#elif LDBL_MANT_DIG == 53
# define NDIGIT_MAX 17
#elif LDBL_MANT_DIG == 113
# define NDIGIT_MAX 36
#elif LDBL_MANT_DIG == 56
# define NDIGIT_MAX 18
#else
/* See IEEE 854 5.6, table 2 for this formula. Unfortunately we need a
compile time constant here, so we cannot use it. */
# error "NDIGIT_MAX must be precomputed"
# define NDIGIT_MAX (lrint (ceil (M_LN2 / M_LN10 * LDBL_MANT_DIG + 1.0)))
#endif
#include "efgcvt.c"