2 * Copyright (c) 2003 David Schultz <das@FreeBSD.ORG>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
39 * ldtoa() is a wrapper for gdtoa() that makes it smell like dtoa(),
40 * except that the floating point argument is passed by reference.
41 * When dtoa() is passed a NaN or infinity, it sets expt to 9999.
42 * However, a long double could have a valid exponent of 9999, so we
43 * use INT_MAX in ldtoa() instead.
46 __ldtoa(long double *ld, int mode, int ndigits, int *decpt, int *sign,
50 LDBL_MANT_DIG, /* nbits */
51 LDBL_MIN_EXP - LDBL_MANT_DIG, /* emin */
52 LDBL_MAX_EXP - LDBL_MANT_DIG, /* emax */
53 FPI_Round_near, /* rounding */
54 #ifdef Sudden_Underflow /* unused, but correct anyway */
63 uint32_t bits[(LDBL_MANT_DIG + 31) / 32];
67 be = u.bits.exp - (LDBL_MAX_EXP - 1) - (LDBL_MANT_DIG - 1);
68 LDBL_TO_ARRAY32(u, bits);
70 switch (fpclassify(u.e)) {
73 #ifdef LDBL_IMPLICIT_NBIT
74 bits[LDBL_MANT_DIG / 32] |= 1 << ((LDBL_MANT_DIG - 1) % 32);
75 #endif /* LDBL_IMPLICIT_NBIT */
81 kind = STRTOG_Denormal;
85 kind = STRTOG_Infinite;
94 ret = gdtoa(&fpi, be, (ULong *)bits, &kind, mode, ndigits, decpt, rve);