/* error-checking interface to strtod-like functions Copyright (C) 1996, 1999-2000, 2003-2006, 2009-2015 Free Software Foundation, Inc. This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program 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 General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see . */ /* Written by Jim Meyering. */ #include #include "xstrtod.h" #include #include #include #if LONG # define XSTRTOD xstrtold # define DOUBLE long double #else # define XSTRTOD xstrtod # define DOUBLE double #endif /* An interface to a string-to-floating-point conversion function that encapsulates all the error checking one should usually perform. Like strtod/strtold, but upon successful conversion put the result in *RESULT and return true. Return false and don't modify *RESULT upon any failure. CONVERT specifies the conversion function, e.g., strtod itself. */ bool XSTRTOD (char const *str, char const **ptr, DOUBLE *result, DOUBLE (*convert) (char const *, char **)) { DOUBLE val; char *terminator; bool ok = true; errno = 0; val = convert (str, &terminator); /* Having a non-zero terminator is an error only when PTR is NULL. */ if (terminator == str || (ptr == NULL && *terminator != '\0')) ok = false; else { /* Allow underflow (in which case CONVERT returns zero), but flag overflow as an error. */ if (val != 0 && errno == ERANGE) ok = false; } if (ptr != NULL) *ptr = terminator; *result = val; return ok; }