Mercurial > hg > octave-kai > gnulib-hg
annotate lib/xstrtod.c @ 3063:e0287ca43594
*** empty log message ***
| author | Jim Meyering <jim@meyering.net> |
|---|---|
| date | Tue, 19 Dec 2000 08:16:25 +0000 |
| parents | a81cc8789f1f |
| children | ce37d22a271f |
| rev | line source |
|---|---|
| 569 | 1 /* xstrtod.c - error-checking interface to strtod |
|
2081
a81cc8789f1f
Add #pragma STDC FENV_ACCESS ON if C99.
Jim Meyering <jim@meyering.net>
parents:
1853
diff
changeset
|
2 Copyright (C) 1996, 1999, 2000 Free Software Foundation, Inc. |
| 569 | 3 |
| 4 This program is free software; you can redistribute it and/or modify | |
| 5 it under the terms of the GNU General Public License as published by | |
| 6 the Free Software Foundation; either version 2, or (at your option) | |
| 7 any later version. | |
| 8 | |
| 9 This program is distributed in the hope that it will be useful, | |
| 10 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 12 GNU General Public License for more details. | |
| 13 | |
| 14 You should have received a copy of the GNU General Public License | |
| 570 | 15 along with this program; if not, write to the Free Software Foundation, |
| 16 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ | |
| 569 | 17 |
| 18 /* Written by Jim Meyering. */ | |
| 19 | |
| 513 | 20 #ifdef HAVE_CONFIG_H |
| 653 | 21 # include <config.h> |
| 513 | 22 #endif |
| 23 | |
| 24 #ifdef STDC_HEADERS | |
| 653 | 25 # include <stdlib.h> |
| 513 | 26 #else |
| 27 double strtod (); | |
| 28 #endif | |
| 29 | |
| 30 #include <errno.h> | |
| 31 #include <stdio.h> | |
| 32 #include <limits.h> | |
| 33 #include "xstrtod.h" | |
| 34 | |
|
2081
a81cc8789f1f
Add #pragma STDC FENV_ACCESS ON if C99.
Jim Meyering <jim@meyering.net>
parents:
1853
diff
changeset
|
35 /* Tell the compiler that non-default rounding modes are used. */ |
|
a81cc8789f1f
Add #pragma STDC FENV_ACCESS ON if C99.
Jim Meyering <jim@meyering.net>
parents:
1853
diff
changeset
|
36 #if 199901 <= __STDC_VERSION__ |
|
a81cc8789f1f
Add #pragma STDC FENV_ACCESS ON if C99.
Jim Meyering <jim@meyering.net>
parents:
1853
diff
changeset
|
37 #pragma STDC FENV_ACCESS ON |
|
a81cc8789f1f
Add #pragma STDC FENV_ACCESS ON if C99.
Jim Meyering <jim@meyering.net>
parents:
1853
diff
changeset
|
38 #endif |
|
a81cc8789f1f
Add #pragma STDC FENV_ACCESS ON if C99.
Jim Meyering <jim@meyering.net>
parents:
1853
diff
changeset
|
39 |
| 568 | 40 /* An interface to strtod that encapsulates all the error checking |
| 569 | 41 one should usually perform. Like strtod, but upon successful |
| 42 conversion put the result in *RESULT and return zero. Return | |
| 43 non-zero and don't modify *RESULT upon any failure. */ | |
| 568 | 44 |
| 513 | 45 int |
| 46 xstrtod (str, ptr, result) | |
| 47 const char *str; | |
| 48 const char **ptr; | |
| 49 double *result; | |
| 50 { | |
| 51 double val; | |
| 52 char *terminator; | |
| 53 int fail; | |
| 54 | |
| 55 fail = 0; | |
| 56 errno = 0; | |
| 57 val = strtod (str, &terminator); | |
| 58 | |
| 59 /* Having a non-zero terminator is an error only when PTR is NULL. */ | |
| 60 if (terminator == str || (ptr == NULL && *terminator != '\0')) | |
| 61 fail = 1; | |
| 62 else | |
| 63 { | |
| 64 /* Allow underflow (in which case strtod returns zero), | |
| 65 but flag overflow as an error. */ | |
| 66 if (val != 0.0 && errno == ERANGE) | |
| 67 fail = 1; | |
| 68 } | |
| 69 | |
| 70 if (ptr != NULL) | |
| 71 *ptr = terminator; | |
| 72 | |
| 73 *result = val; | |
| 74 return fail; | |
| 75 } |