diff options
Diffstat (limited to 'sysdeps/generic/strcpy_chk.c')
-rw-r--r-- | sysdeps/generic/strcpy_chk.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/sysdeps/generic/strcpy_chk.c b/sysdeps/generic/strcpy_chk.c new file mode 100644 index 0000000..a4d909f --- /dev/null +++ b/sysdeps/generic/strcpy_chk.c @@ -0,0 +1,68 @@ +/* Copyright (C) 1991, 1997, 2000, 2003, 2004 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <stddef.h> +#include <string.h> +#include <memcopy.h> + +#undef strcpy + +/* Copy SRC to DEST with checking of destination buffer overflow. */ +char * +__strcpy_chk (dest, src, destlen) + char *dest; + const char *src; + size_t destlen; +{ + reg_char c; + char *s = (char *) src; + const ptrdiff_t off = dest - s; + + while (__builtin_expect (destlen >= 4, 0)) + { + c = s[0]; + s[off] = c; + if (c == '\0') + return dest; + c = s[1]; + s[off + 1] = c; + if (c == '\0') + return dest; + c = s[2]; + s[off + 2] = c; + if (c == '\0') + return dest; + c = s[3]; + s[off + 3] = c; + if (c == '\0') + return dest; + destlen -= 4; + s += 4; + } + + do + { + if (__builtin_expect (destlen-- == 0, 0)) + __chk_fail (); + c = *s; + *(s++ + off) = c; + } + while (c != '\0'); + + return dest; +} |