/* Checking gets. Copyright (C) 2005 Free Software Foundation, Inc. This file is part of GCC. GCC 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 2, or (at your option) any later version. In addition to the permissions in the GNU General Public License, the Free Software Foundation gives you unlimited permission to link the compiled version of this file into combinations with other programs, and to distribute those combinations without any restriction coming from the use of this file. (The General Public License restrictions do apply in other respects; for example, they cover modification of the file, and distribution when not linked into a combine executable.) GCC 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 GCC; see the file COPYING. If not, write to the Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ /* As a special exception, if you link this library with files compiled with GCC to produce an executable, this does not cause the resulting executable to be covered by the GNU General Public License. This exception does not however invalidate any other reasons why the executable file might be covered by the GNU General Public License. */ #include "config.h" #include <ssp/ssp.h> #include <stdarg.h> #ifdef HAVE_STDLIB_H # include <stdlib.h> #endif #ifdef HAVE_ALLOCA_H # include <alloca.h> #endif #ifdef HAVE_LIMITS_H # include <limits.h> #endif #ifdef HAVE_STDIO_H # include <stdio.h> #endif #ifdef HAVE_STRING_H # include <string.h> #endif extern void __chk_fail (void) __attribute__((__noreturn__)); char * __gets_chk (char *s, size_t slen) { char *ret, *buf; if (slen >= (size_t) INT_MAX) return gets (s); if (slen <= 8192) buf = alloca (slen + 1); else buf = malloc (slen + 1); if (buf == NULL) return gets (s); ret = fgets (buf, (int) (slen + 1), stdin); if (ret != NULL) { size_t len = strlen (buf); if (len > 0 && buf[len - 1] == '\n') --len; if (len == slen) __chk_fail (); memcpy (s, buf, len); s[len] = '\0'; ret = s; } if (slen > 8192) free (buf); return ret; }