On powerpc64le, long double can currently take two formats: the same as
double (-mlong-double-64) or IBM Extended Precision (default with
-mlong-double-128 or explicitly with -mabi=ibmlongdouble). The internal
implementation of printf-like functions is aware of these possibilities
and properly parses floating-point values from the variable arguments,
before making calls to __printf_fp and __printf_fphex. These functions
are also aware of the format possibilities and know how to convert both
formats to string.
When library support for TS 18661-3 was added to glibc, __printf_fp and
__printf_fphex were extended with support for an additional type
(__float128/_Float128) with a different format (binary128). Now that
powerpc64le is getting support for its third long double format, and
taking into account that this format is the same as the format of
__float128/_Float128, this patch extends __vfprintf_internal to properly
call __printf_fp and __printf_fphex with this new format.
Tested for powerpc64le (with additional patches to actually enable the
use of these preparations) and for x86_64.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
After all that prep work, nldbl-compat.c can now use PRINTF_LDBL_IS_DBL
instead of __no_long_double to control the behavior of printf-like
functions; this is the last thing we needed __no_long_double for, so it
can go away entirely.
Tested for powerpc and powerpc64le.
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.
There are a lot more printf variants than there are scanf variants,
and the code for setting up and tearing down their custom FILE
variants around the call to __vf(w)printf is more complicated and
variable. Therefore, I have added _internal versions of all the
v*printf variants, rather than introducing helper routines so that
they can all directly call __vf(w)printf_internal, as was done with
scanf.
As with the scanf changes, in this patch the _internal functions still
look at the environmental mode bits and all callers pass 0 for the
flags parameter.
Several of the affected public functions had _IO_ name aliases that
were not exported (but, in one case, appeared in libio.h anyway);
I was originally planning to leave them as aliases to avoid having
to touch internal callers, but it turns out ldbl_*_alias only work
for exported symbols, so they've all been removed instead. It also
turns out there were hardly any internal callers. _IO_vsprintf and
_IO_vfprintf *are* exported, so those two stick around.
Summary for the changes to each of the affected symbols:
_IO_vfprintf, _IO_vsprintf:
All internal calls removed, thus the internal declarations, as well
as uses of libc_hidden_proto and libc_hidden_def, were also removed.
The external symbol is now exposed via uses of ldbl_strong_alias
to __vfprintf_internal and __vsprintf_internal, respectively.
_IO_vasprintf, _IO_vdprintf, _IO_vsnprintf,
_IO_vfwprintf, _IO_vswprintf,
_IO_obstack_vprintf, _IO_obstack_printf:
All internal calls removed, thus declaration in internal headers
were also removed. They were never exported, so there are no
aliases tying them to the internal functions. I.e.: entirely gone.
__vsnprintf:
Internal calls were always preceded by macros such as
#define __vsnprintf _IO_vsnprintf, and
#define __vsnprintf vsnprintf
The macros were removed and their uses replaced with calls to the
new internal function __vsnprintf_internal. Since there were no
internal calls, the internal declaration was also removed. The
external symbol is preserved with ldbl_weak_alias to ___vsnprintf.
__vfwprintf:
All internal calls converted into calls to __vfwprintf_internal,
thus the internal declaration was removed. The function is now a
wrapper that calls __vfwprintf_internal. The external symbol is
preserved.
__vswprintf:
Similarly, but no external symbol.
__vasprintf, __vdprintf, __vfprintf, __vsprintf:
New internal wrappers. Not exported.
vasprintf, vdprintf, vfprintf, vsprintf, vsnprintf,
vfwprintf, vswprintf,
obstack_vprintf, obstack_printf:
These functions used to be aliases to the respective _IO_* function,
they are now aliases to their respective __* functions.
Tested for powerpc and powerpc64le.