Use PRINTF_FORTIFY instead of _IO_FLAGS2_FORTIFY (bug 11319)

The _chk variants of all of the printf functions become much simpler.
This is the last thing that we needed _IO_acquire_lock_clear_flags2
for, so it can go as well.  I took the opportunity to make the headers
included and the names of all local variables consistent across all the
affected files.

Since we ultimately want to get rid of __no_long_double as well, it
must be possible to get all of the nontrivial effects of the _chk
functions by calling the _internal functions with appropriate flags.
For most of the __(v)xprintf_chk functions, this is covered by
PRINTF_FORTIFY plus some up-front argument checks that can be
duplicated.  However, __(v)sprintf_chk installs a custom jump table so
that it can crash instead of overflowing the output buffer.  This
functionality is moved to __vsprintf_internal, which now has a
'maxlen' argument like __vsnprintf_internal; to get the unsafe
behavior of ordinary (v)sprintf, pass -1 for that argument.

obstack_printf_chk and obstack_vprintf_chk are no longer in the same
file.

As a side-effect of the unification of both fortified and non-fortified
vdprintf initialization, this patch fixes bug 11319 for __dprintf_chk
and __vdprintf_chk, which was previously fixed only for dprintf and
vdprintf by the commit

commit 7ca890b88e6ab7624afb1742a9fffb37ad5b3fc3
Author: Ulrich Drepper <drepper@redhat.com>
Date:   Wed Feb 24 16:07:57 2010 -0800

    Fix reporting of I/O errors in *dprintf functions.

This patch adds a test case to avoid regressions.

Tested for powerpc and powerpc64le.

1 files changed, 9 insertions, 18 deletions

diff --git a/libio/libioP.h b/libio/libioP.h
index fe52ef1..ce5228e 100644
--- a/libio/libioP.h
+++ b/libio/libioP.h
@@ -677,9 +677,16 @@ extern int __obstack_vprintf_internal (struct obstack *ob, const char *fmt,
 				       va_list ap, unsigned int mode_flags)
     attribute_hidden;
 
-extern int __vsprintf_internal (char *string, const char *format, va_list ap,
+/* Note: __vsprintf_internal, unlike vsprintf, does take a maxlen argument,
+   because it's called by both vsprintf and vsprintf_chk.  If maxlen is
+   not set to -1, overrunning the buffer will cause a prompt crash.
+   This is the behavior of ordinary (v)sprintf functions, thus they call
+   __vsprintf_internal with that argument set to -1.  */
+extern int __vsprintf_internal (char *string, size_t maxlen,
+				const char *format, va_list ap,
 				unsigned int mode_flags)
     attribute_hidden;
+
 extern int __vsnprintf_internal (char *string, size_t maxlen,
 				 const char *format, va_list ap,
 				 unsigned int mode_flags)
@@ -818,26 +825,10 @@ _IO_acquire_lock_fct (FILE **p)
     _IO_funlockfile (fp);
 }
 
-static inline void
-__attribute__ ((__always_inline__))
-_IO_acquire_lock_clear_flags2_fct (FILE **p)
-{
-  FILE *fp = *p;
-  fp->_flags2 &= ~(_IO_FLAGS2_FORTIFY);
-  if ((fp->_flags & _IO_USER_LOCK) == 0)
-    _IO_funlockfile (fp);
-}
-
 #if !defined _IO_MTSAFE_IO && IS_IN (libc)
 # define _IO_acquire_lock(_fp)						      \
-  do {									      \
-    FILE *_IO_acquire_lock_file = NULL
-# define _IO_acquire_lock_clear_flags2(_fp)				      \
-  do {									      \
-    FILE *_IO_acquire_lock_file = (_fp)
+  do {
 # define _IO_release_lock(_fp)						      \
-    if (_IO_acquire_lock_file != NULL)					      \
-      _IO_acquire_lock_file->_flags2 &= ~(_IO_FLAGS2_FORTIFY);		      \
   } while (0)
 #endif