1 | /* Compatibility functions for floating point formatting. |
2 | Copyright (C) 1995-2016 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
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. |
9 | |
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. |
14 | |
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/>. */ |
18 | |
19 | #include <math.h> |
20 | #include <stdio.h> |
21 | #include <stdlib.h> |
22 | #include <sys/param.h> |
23 | #include <float.h> |
24 | #include <libc-lock.h> |
25 | #include <math_ldbl_opt.h> |
26 | |
27 | #ifndef FLOAT_TYPE |
28 | # define FLOAT_TYPE double |
29 | # define FUNC_PREFIX |
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 |
38 | # define NDIGIT_MAX 9 |
39 | # elif DBL_MANT_DIG == 56 |
40 | # define NDIGIT_MAX 18 |
41 | # else |
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))) |
46 | # endif |
47 | #else |
48 | # define LONG_DOUBLE_CVT |
49 | #endif |
50 | |
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 |
55 | |
56 | |
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) |
60 | |
61 | |
62 | static char FCVT_BUFFER[MAXDIG]; |
63 | static char ECVT_BUFFER[MAXDIG]; |
64 | libc_freeres_ptr (static char *FCVT_BUFPTR); |
65 | |
66 | char * |
67 | __APPEND (FUNC_PREFIX, fcvt) (FLOAT_TYPE value, int ndigit, int *decpt, |
68 | int *sign) |
69 | { |
70 | if (FCVT_BUFPTR == NULL) |
71 | { |
72 | if (__APPEND (FUNC_PREFIX, fcvt_r) (value, ndigit, decpt, sign, |
73 | FCVT_BUFFER, MAXDIG) != -1) |
74 | return FCVT_BUFFER; |
75 | |
76 | FCVT_BUFPTR = (char *) malloc (FCVT_MAXDIG); |
77 | if (FCVT_BUFPTR == NULL) |
78 | return FCVT_BUFFER; |
79 | } |
80 | |
81 | (void) __APPEND (FUNC_PREFIX, fcvt_r) (value, ndigit, decpt, sign, |
82 | FCVT_BUFPTR, FCVT_MAXDIG); |
83 | |
84 | return FCVT_BUFPTR; |
85 | } |
86 | |
87 | |
88 | char * |
89 | __APPEND (FUNC_PREFIX, ecvt) (FLOAT_TYPE value, int ndigit, int *decpt, |
90 | int *sign) |
91 | { |
92 | (void) __APPEND (FUNC_PREFIX, ecvt_r) (value, ndigit, decpt, sign, |
93 | ECVT_BUFFER, MAXDIG); |
94 | |
95 | return ECVT_BUFFER; |
96 | } |
97 | |
98 | char * |
99 | __APPEND (FUNC_PREFIX, gcvt) (FLOAT_TYPE value, int ndigit, char *buf) |
100 | { |
101 | sprintf (buf, "%.*" FLOAT_FMT_FLAG "g" , MIN (ndigit, NDIGIT_MAX), value); |
102 | return buf; |
103 | } |
104 | |
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) |
112 | # else |
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) |
119 | # endif |
120 | #else |
121 | # define cvt_symbol(symbol) \ |
122 | strong_alias (__APPEND (FUNC_PREFIX, symbol), APPEND (FUNC_PREFIX, symbol)) |
123 | #endif |
124 | cvt_symbol(fcvt); |
125 | cvt_symbol(ecvt); |
126 | cvt_symbol(gcvt); |
127 | |