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1 /* Compatibility functions for floating point formatting.
2 Copyright (C) 1995-2018 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
22 #include <sys/param.h>
24 #include <libc-lock.h>
25 #include <math_ldbl_opt.h>
28 # define FLOAT_TYPE double
30 # define FLOAT_FMT_FLAG
31 /* Actually we have to write (DBL_DIG + log10 (DBL_MAX_10_EXP)) but we
32 don't have log10 available in the preprocessor. */
33 # define MAXDIG (NDIGIT_MAX + 3)
34 # define FCVT_MAXDIG (DBL_MAX_10_EXP + MAXDIG)
35 # if DBL_MANT_DIG == 53
36 # define NDIGIT_MAX 17
37 # elif DBL_MANT_DIG == 24
39 # elif DBL_MANT_DIG == 56
40 # define NDIGIT_MAX 18
42 /* See IEEE 854 5.6, table 2 for this formula. Unfortunately we need a
43 compile time constant here, so we cannot use it. */
44 # error "NDIGIT_MAX must be precomputed"
45 # define NDIGIT_MAX (lrint (ceil (M_LN2 / M_LN10 * DBL_MANT_DIG + 1.0)))
48 # define LONG_DOUBLE_CVT
51 #define APPEND(a, b) APPEND2 (a, b)
52 #define APPEND2(a, b) a##b
53 #define __APPEND(a, b) __APPEND2 (a, b)
54 #define __APPEND2(a, b) __##a##b
57 #define FCVT_BUFFER APPEND (FUNC_PREFIX, fcvt_buffer)
58 #define FCVT_BUFPTR APPEND (FUNC_PREFIX, fcvt_bufptr)
59 #define ECVT_BUFFER APPEND (FUNC_PREFIX, ecvt_buffer)
62 static char FCVT_BUFFER
[MAXDIG
];
63 static char ECVT_BUFFER
[MAXDIG
];
64 libc_freeres_ptr (static char *FCVT_BUFPTR
);
67 __APPEND (FUNC_PREFIX
, fcvt
) (FLOAT_TYPE value
, int ndigit
, int *decpt
,
70 if (FCVT_BUFPTR
== NULL
)
72 if (__APPEND (FUNC_PREFIX
, fcvt_r
) (value
, ndigit
, decpt
, sign
,
73 FCVT_BUFFER
, MAXDIG
) != -1)
76 FCVT_BUFPTR
= (char *) malloc (FCVT_MAXDIG
);
77 if (FCVT_BUFPTR
== NULL
)
81 (void) __APPEND (FUNC_PREFIX
, fcvt_r
) (value
, ndigit
, decpt
, sign
,
82 FCVT_BUFPTR
, FCVT_MAXDIG
);
89 __APPEND (FUNC_PREFIX
, ecvt
) (FLOAT_TYPE value
, int ndigit
, int *decpt
,
92 (void) __APPEND (FUNC_PREFIX
, ecvt_r
) (value
, ndigit
, decpt
, sign
,
99 __APPEND (FUNC_PREFIX
, gcvt
) (FLOAT_TYPE value
, int ndigit
, char *buf
)
101 sprintf (buf
, "%.*" FLOAT_FMT_FLAG
"g", MIN (ndigit
, NDIGIT_MAX
), value
);
105 #if LONG_DOUBLE_COMPAT (libc, GLIBC_2_0)
106 # ifdef LONG_DOUBLE_CVT
107 # define cvt_symbol(symbol) \
108 cvt_symbol_1 (libc, __APPEND (FUNC_PREFIX, symbol), \
109 APPEND (FUNC_PREFIX, symbol), GLIBC_2_4)
110 # define cvt_symbol_1(lib, local, symbol, version) \
111 versioned_symbol (lib, local, symbol, version)
113 # define cvt_symbol(symbol) \
114 cvt_symbol_1 (libc, __APPEND (FUNC_PREFIX, symbol), \
115 APPEND (q, symbol), GLIBC_2_0); \
116 strong_alias (__APPEND (FUNC_PREFIX, symbol), APPEND (FUNC_PREFIX, symbol))
117 # define cvt_symbol_1(lib, local, symbol, version) \
118 compat_symbol (lib, local, symbol, version)
121 # define cvt_symbol(symbol) \
122 strong_alias (__APPEND (FUNC_PREFIX, symbol), APPEND (FUNC_PREFIX, symbol))