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-rw-r--r--debug/vsnprintf_chk.c70
1 files changed, 70 insertions, 0 deletions
diff --git a/debug/vsnprintf_chk.c b/debug/vsnprintf_chk.c
new file mode 100644
index 0000000000..850cd5af5a
--- /dev/null
+++ b/debug/vsnprintf_chk.c
@@ -0,0 +1,70 @@
+/* Copyright (C) 1991, 1995, 1997, 1998, 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 <stdarg.h>
+#include <stdio.h>
+#include "../libio/libioP.h"
+#include "../libio/strfile.h"
+
+extern const struct _IO_jump_t _IO_strn_jumps attribute_hidden;
+
+/* Write formatted output into S, according to the format
+ string FORMAT, writing no more than MAXLEN characters. */
+/* VARARGS5 */
+int
+__vsnprintf_chk (char *s, size_t maxlen, int flags, size_t slen,
+ const char *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_strnfile sf;
+ 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 (maxlen == 0)
+ {
+ s = sf.overflow_buf;
+ maxlen = sizeof (sf.overflow_buf);
+ }
+
+ _IO_no_init (&sf.f._sbf._f, _IO_USER_LOCK, -1, NULL, NULL);
+ _IO_JUMPS ((struct _IO_FILE_plus *) &sf.f._sbf) = &_IO_strn_jumps;
+ s[0] = '\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_CHECK_PERCENT_N;
+
+ _IO_str_init_static_internal (&sf.f, s, maxlen - 1, s);
+ ret = INTUSE(_IO_vfprintf) ((_IO_FILE *) &sf.f._sbf, format, args);
+
+ if (sf.f._sbf._f._IO_buf_base != sf.overflow_buf)
+ *sf.f._sbf._f._IO_write_ptr = '\0';
+ return ret;
+}
+libc_hidden_def (__vsnprintf_chk)