diff options
Diffstat (limited to 'debug/vswprintf_chk.c')
-rw-r--r-- | debug/vswprintf_chk.c | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/debug/vswprintf_chk.c b/debug/vswprintf_chk.c new file mode 100644 index 0000000..f9a50c6 --- /dev/null +++ b/debug/vswprintf_chk.c @@ -0,0 +1,75 @@ +/* Copyright (C) 1991,1995,1997,1998,2004,2005 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 <stdarg.h> +#include <wchar.h> +#include "../libio/libioP.h" +#include "../libio/strfile.h" + + +/* Write formatted output into S, according to the format + string FORMAT, writing no more than MAXLEN characters. */ +/* VARARGS5 */ +int +__vswprintf_chk (wchar_t *s, size_t maxlen, int flags, size_t slen, + const wchar_t *format, va_list args) +{ + /* XXX Maybe for less strict version do not fail immediately. + Though, maxlen is supposed to be the size of buffer pointed + to by s, so a conforming program can't pass such maxlen + to *snprintf. */ + if (__builtin_expect (slen < maxlen, 0)) + __chk_fail (); + + _IO_wstrnfile sf; + struct _IO_wide_data wd; + int ret; +#ifdef _IO_MTSAFE_IO + sf.f._sbf._f._lock = NULL; +#endif + + /* We need to handle the special case where MAXLEN is 0. Use the + overflow buffer right from the start. */ + if (__builtin_expect (maxlen == 0, 0)) + /* Since we have to write at least the terminating L'\0' a buffer + length of zero always makes the function fail. */ + return -1; + + _IO_no_init (&sf.f._sbf._f, _IO_USER_LOCK, 0, &wd, &_IO_wstrn_jumps); + _IO_fwide (&sf.f._sbf._f, 1); + s[0] = L'\0'; + + /* For flags > 0 (i.e. __USE_FORTIFY_LEVEL > 1) request that %n + can only come from read-only format strings. */ + if (flags > 0) + sf.f._sbf._f._flags2 |= _IO_FLAGS2_FORTIFY; + + _IO_wstr_init_static (&sf.f._sbf._f, s, maxlen - 1, s); + ret = _IO_vfwprintf ((_IO_FILE *) &sf.f._sbf, format, args); + + if (sf.f._sbf._f._wide_data->_IO_buf_base == sf.overflow_buf) + /* ISO C99 requires swprintf/vswprintf to return an error if the + output does not fit int he provided buffer. */ + return -1; + + /* Terminate the string. */ + *sf.f._sbf._f._wide_data->_IO_write_ptr = '\0'; + + return ret; +} +libc_hidden_def (__vswprintf_chk) |