diff options
Diffstat (limited to 'stdlib/strtod_nan_main.c')
-rw-r--r-- | stdlib/strtod_nan_main.c | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/stdlib/strtod_nan_main.c b/stdlib/strtod_nan_main.c new file mode 100644 index 0000000000..bc37a63a27 --- /dev/null +++ b/stdlib/strtod_nan_main.c @@ -0,0 +1,63 @@ +/* Convert string for NaN payload to corresponding NaN. + Copyright (C) 1997-2015 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 + <http://www.gnu.org/licenses/>. */ + +#include <ieee754.h> +#include <locale.h> +#include <math.h> +#include <stdlib.h> +#include <wchar.h> + + +/* If STR starts with an optional n-char-sequence as defined by ISO C + (a sequence of ASCII letters, digits and underscores), followed by + ENDC, return a NaN whose payload is set based on STR. Otherwise, + return a default NAN. If ENDPTR is not NULL, set *ENDPTR to point + to the character after the initial n-char-sequence. */ + +internal_function +FLOAT +STRTOD_NAN (const STRING_TYPE *str, STRING_TYPE **endptr, STRING_TYPE endc) +{ + const STRING_TYPE *cp = str; + + while ((*cp >= L_('0') && *cp <= L_('9')) + || (*cp >= L_('A') && *cp <= L_('Z')) + || (*cp >= L_('a') && *cp <= L_('z')) + || *cp == L_('_')) + ++cp; + + FLOAT retval = NAN; + if (*cp != endc) + goto out; + + /* This is a system-dependent way to specify the bitmask used for + the NaN. We expect it to be a number which is put in the + mantissa of the number. */ + STRING_TYPE *endp; + unsigned long long int mant; + + mant = STRTOULL (str, &endp, 0); + if (endp == cp) + SET_MANTISSA (retval, mant); + + out: + if (endptr != NULL) + *endptr = (STRING_TYPE *) cp; + return retval; +} +libc_hidden_def (STRTOD_NAN) |