-/* [efg]cvt -- compatibility functions for floating point formatting,
- reentrant versions.
-Copyright (C) 1995, 1996 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 Library General Public License as
-published by the Free Software Foundation; either version 2 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
-Library General Public License for more details.
-
-You should have received a copy of the GNU Library General Public
-License along with the GNU C Library; see the file COPYING.LIB. If
-not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA. */
+/* Compatibility functions for floating point formatting, reentrant versions.
+ Copyright (C) 1995-2019 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, see
+ <https://www.gnu.org/licenses/>. */
#include <errno.h>
+#include <float.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <math.h>
#include <stdlib.h>
+#include <sys/param.h>
+#include <math_ldbl_opt.h>
#ifndef FLOAT_TYPE
-#define FLOAT_TYPE double
-#define FUNC_PREFIX
-#define FLOAT_FMT_FLAG
-#define FLOAT_NAME_EXT
+# define FLOAT_TYPE double
+# define FUNC_PREFIX
+# define FLOAT_FMT_FLAG
+# define FLOAT_NAME_EXT
+# define FLOAT_MIN_10_EXP DBL_MIN_10_EXP
+# if DBL_MANT_DIG == 53
+# define NDIGIT_MAX 17
+# elif DBL_MANT_DIG == 24
+# define NDIGIT_MAX 9
+# elif DBL_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 * DBL_MANT_DIG + 1.0)))
+# endif
+# if DBL_MIN_10_EXP == -37
+# define FLOAT_MIN_10_NORM 1.0e-37
+# elif DBL_MIN_10_EXP == -307
+# define FLOAT_MIN_10_NORM 1.0e-307
+# elif DBL_MIN_10_EXP == -4931
+# define FLOAT_MIN_10_NORM 1.0e-4931
+# else
+/* libc can't depend on libm. */
+# error "FLOAT_MIN_10_NORM must be precomputed"
+# define FLOAT_MIN_10_NORM exp10 (DBL_MIN_10_EXP)
+# endif
+#else
+# define LONG_DOUBLE_CVT
#endif
#define APPEND(a, b) APPEND2 (a, b)
#define APPEND2(a, b) a##b
+#define __APPEND(a, b) __APPEND2 (a, b)
+#define __APPEND2(a, b) __##a##b
#define FLOOR APPEND(floor, FLOAT_NAME_EXT)
#define FABS APPEND(fabs, FLOAT_NAME_EXT)
#define LOG10 APPEND(log10, FLOAT_NAME_EXT)
+#define EXP APPEND(exp, FLOAT_NAME_EXT)
int
-APPEND (FUNC_PREFIX, fcvt_r) (value, ndigit, decpt, sign, buf, len)
- FLOAT_TYPE value;
- int ndigit, *decpt, *sign;
- char *buf;
- size_t len;
+__APPEND (FUNC_PREFIX, fcvt_r) (FLOAT_TYPE value, int ndigit, int *decpt,
+ int *sign, char *buf, size_t len)
{
- int n, i;
+ ssize_t n;
+ ssize_t i;
+ int left;
if (buf == NULL)
{
return -1;
}
- *sign = value < 0.0;
- if (*sign)
- value = - value;
+ left = 0;
+ if (isfinite (value))
+ {
+ *sign = signbit (value) != 0;
+ if (*sign)
+ value = -value;
+
+ if (ndigit < 0)
+ {
+ /* Rounding to the left of the decimal point. */
+ while (ndigit < 0)
+ {
+ FLOAT_TYPE new_value = value * 0.1;
+
+ if (new_value < 1.0)
+ {
+ ndigit = 0;
+ break;
+ }
+
+ value = new_value;
+ ++left;
+ ++ndigit;
+ }
+ }
+ }
+ else
+ /* Value is Inf or NaN. */
+ *sign = 0;
- n = snprintf (buf, len, "%.*" FLOAT_FMT_FLAG "f", ndigit, value);
- if (n < 0)
+ n = __snprintf (buf, len, "%.*" FLOAT_FMT_FLAG "f", MIN (ndigit, NDIGIT_MAX),
+ value);
+ /* Check for a too small buffer. */
+ if (n >= (ssize_t) len)
return -1;
i = 0;
while (i < n && isdigit (buf[i]))
++i;
*decpt = i;
- do
- ++i;
- while (! isdigit (buf[i]));
- memmove (&buf[i - *decpt], buf, n - (i - *decpt));
+
+ if (i == 0)
+ /* Value is Inf or NaN. */
+ return 0;
+
+ if (i < n)
+ {
+ do
+ ++i;
+ while (i < n && !isdigit (buf[i]));
+
+ if (*decpt == 1 && buf[0] == '0' && value != 0.0)
+ {
+ /* We must not have leading zeroes. Strip them all out and
+ adjust *DECPT if necessary. */
+ --*decpt;
+ while (i < n && buf[i] == '0')
+ {
+ --*decpt;
+ ++i;
+ }
+ }
+
+ memmove (&buf[MAX (*decpt, 0)], &buf[i], n - i);
+ buf[n - (i - MAX (*decpt, 0))] = '\0';
+ }
+
+ if (left)
+ {
+ *decpt += left;
+ if ((ssize_t) --len > n)
+ {
+ while (left-- > 0 && n < (ssize_t) len)
+ buf[n++] = '0';
+ buf[n] = '\0';
+ }
+ }
return 0;
}
-#define weak_extern2(name) weak_extern (name)
-weak_extern2 (FLOOR) weak_extern2 (LOG10) weak_extern2 (FABS)
-
int
-APPEND (FUNC_PREFIX, ecvt_r) (value, ndigit, decpt, sign, buf, len)
- FLOAT_TYPE value;
- int ndigit, *decpt, *sign;
- char *buf;
- size_t len;
+__APPEND (FUNC_PREFIX, ecvt_r) (FLOAT_TYPE value, int ndigit, int *decpt,
+ int *sign, char *buf, size_t len)
{
- FLOAT_TYPE (*log10_function) (FLOAT_TYPE) = &LOG10;
+ int exponent = 0;
- if (log10_function)
- {
- /* Use the reasonable code if -lm is included. */
- ndigit -= (int) FLOOR (LOG10 (FABS (value)));
- if (ndigit < 0)
- ndigit = 0;
- }
- else
+ if (isfinite (value) && value != 0.0)
{
/* Slow code that doesn't require -lm functions. */
FLOAT_TYPE d;
- for (d = value < 0.0 ? - value : value;
- ndigit > 0 && d >= 10.0;
- d *= 0.1)
- --ndigit;
+ FLOAT_TYPE f = 1.0;
+ if (value < 0.0)
+ d = -value;
+ else
+ d = value;
+ /* For denormalized numbers the d < 1.0 case below won't work,
+ as f can overflow to +Inf. */
+ if (d < FLOAT_MIN_10_NORM)
+ {
+ value /= FLOAT_MIN_10_NORM;
+ if (value < 0.0)
+ d = -value;
+ else
+ d = value;
+ exponent += FLOAT_MIN_10_EXP;
+ }
+ if (d < 1.0)
+ {
+ do
+ {
+ f *= 10.0;
+ --exponent;
+ }
+ while (d * f < 1.0);
+
+ value *= f;
+ }
+ else if (d >= 10.0)
+ {
+ do
+ {
+ f *= 10;
+ ++exponent;
+ }
+ while (d >= f * 10.0);
+
+ value /= f;
+ }
}
+ else if (value == 0.0)
+ /* SUSv2 leaves it unspecified whether *DECPT is 0 or 1 for 0.0.
+ This could be changed to -1 if we want to return 0. */
+ exponent = 0;
- return APPEND (FUNC_PREFIX, fcvt_r) (value, ndigit, decpt, sign, buf, len);
+ if (ndigit <= 0 && len > 0)
+ {
+ buf[0] = '\0';
+ *decpt = 1;
+ *sign = isfinite (value) ? signbit (value) != 0 : 0;
+ }
+ else
+ if (__APPEND (FUNC_PREFIX, fcvt_r) (value, MIN (ndigit, NDIGIT_MAX) - 1,
+ decpt, sign, buf, len))
+ return -1;
+
+ *decpt += exponent;
+ return 0;
}
+
+#if LONG_DOUBLE_COMPAT (libc, GLIBC_2_0)
+# ifdef LONG_DOUBLE_CVT
+# define cvt_symbol(symbol) \
+ cvt_symbol_1 (libc, __APPEND (FUNC_PREFIX, symbol), \
+ APPEND (FUNC_PREFIX, symbol), GLIBC_2_4)
+# define cvt_symbol_1(lib, local, symbol, version) \
+ libc_hidden_def (local) \
+ versioned_symbol (lib, local, symbol, version)
+# else
+# define cvt_symbol(symbol) \
+ cvt_symbol_1 (libc, __APPEND (FUNC_PREFIX, symbol), \
+ APPEND (q, symbol), GLIBC_2_0); \
+ weak_alias (__APPEND (FUNC_PREFIX, symbol), APPEND (FUNC_PREFIX, symbol))
+# define cvt_symbol_1(lib, local, symbol, version) \
+ libc_hidden_def (local) \
+ compat_symbol (lib, local, symbol, version)
+# endif
+#else
+# define cvt_symbol(symbol) \
+ cvt_symbol_1 (__APPEND (FUNC_PREFIX, symbol), APPEND (FUNC_PREFIX, symbol))
+# define cvt_symbol_1(local, symbol) \
+ libc_hidden_def (local) \
+ weak_alias (local, symbol)
+#endif
+cvt_symbol(fcvt_r);
+cvt_symbol(ecvt_r);
projects / thirdparty / glibc.git / blobdiff