Mercurial > projects > pwm
view compat/asprintf.c @ 33:fa93d2ff9c62
Prevent potential division by zero
Add safeguard ensuring that there is at least one possible character to
generate passwords from in order to exclude the possibility of a division by
zero error in rand_uniform.
author | Guido Berhoerster <guido+pwm@berhoerster.name> |
---|---|
date | Tue, 30 Jul 2019 20:38:08 +0200 |
parents | a7e41e1a79c8 |
children |
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/* * Copyright (C) 2015 Guido Berhoerster <guido+pwm@berhoerster.name> * * Permission is hereby granted, free of charge, to any person obtaining * a copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice shall be included * in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ #include <stdlib.h> #include <stdio.h> #include <string.h> #include <errno.h> #include "asprintf.h" int vasprintf(char **strp, const char *fmt, va_list args) { int len; va_list args_new; char *str; *strp = NULL; va_copy(args_new, args); len = vsnprintf(NULL, 0, fmt, args); if (len < 0) { goto out; } str = malloc(len + 1); if (str == NULL) { goto out; } len = vsnprintf(str, len + 1, fmt, args_new); if (len < 0) { free(str); goto out; } *strp = str; out: va_end(args_new); return (len); } int asprintf(char **strp, const char *fmt, ...) { int len; va_list args; va_start(args, fmt); len = vasprintf(strp, fmt, args); va_end(args); return (len); }