2019-01-01 08:11:28 +08:00
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/* Copyright (C) 2005-2019 Free Software Foundation, Inc.
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2005-07-20 07:46:55 +08:00
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This file is part of the GNU C Library.
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Contributed by Ulrich Drepper <drepper@gnu.org>.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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2012-02-10 07:18:22 +08:00
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License along with the GNU C Library; if not, see
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<http://www.gnu.org/licenses/>. */
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2005-07-20 07:46:55 +08:00
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#include <stdarg.h>
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#include <stdio.h>
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getopt: clean up error reporting
getopt can print a whole bunch of error messages, and when used
standalone (from gnulib) it uses fprintf to do that. But fprintf is a
cancellation point and getopt isn't, and also applying fprintf to a
stream in wide-character mode is not allowed.
glibc has an internal function called __fxprintf that writes a narrow
format string to a stream regardless of mode, but it only handles
ASCII format strings, and it's still a cancellation point. getopt's
messages are translated, so they might not be ASCII. So getopt has an
error message to an asprintf buffer, monkeys with internal flag bits
on stderr to disable cancellation, and then calls
__fxprintf(stderr, "%s", buffer). There isn't even a helper function,
the code is duplicated every time.
This patch fixes __fxprintf to handle arbitrary multibyte format
strings, and adds a variant __fxprintf_nocancel that does the same
thing but also isn't a cancellation point. (It still _works_ by
monkeying with internal flag bits on the FILE, but that's not really a
layering violation for code in stdio-common.) All of the #ifdef _LIBC
blocks can then be reduced to their standalone versions with a little
help from some macros at the top of the file.
I also wrote a test case to verify that getopt really isn't a
cancellation point, and I'm glad I did, because it found two bugs, one
of which wasn't even to do with cancellation (see previous patch).
* stdio-common/fxprintf.c (__fxprintf_nocancel): New function.
(locked_vfxprintf): New helper function. Handle arbitrary
multibyte strings, not just ASCII.
* include/stdio.h: Declare __fxprintf_nocancel.
* posix/getopt.c: When _LIBC is defined, define fprintf to
__fxprintf_nocancel, flockfile to _IO_flockfile, and
funlockfile to _IO_funlockfile. When neither _LIBC nor
_POSIX_THREAD_SAFE_FUNCTIONS is defined, define flockfile and
funlockfile as no-ops. (_getopt_internal_r): Remove all
internal #ifdef _LIBC blocks; the standalone error-printing
code can now be used for libc as well. Add an
flockfile/funlockfile pair around one case where the error
message is printed in several chunks. Don't use fputc.
* posix/tst-getopt-cancel.c: New test.
* posix/Makefile: Run it.
2017-04-01 22:17:44 +08:00
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#include <stdlib.h>
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2005-07-22 00:23:54 +08:00
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#include <string.h>
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getopt: clean up error reporting
getopt can print a whole bunch of error messages, and when used
standalone (from gnulib) it uses fprintf to do that. But fprintf is a
cancellation point and getopt isn't, and also applying fprintf to a
stream in wide-character mode is not allowed.
glibc has an internal function called __fxprintf that writes a narrow
format string to a stream regardless of mode, but it only handles
ASCII format strings, and it's still a cancellation point. getopt's
messages are translated, so they might not be ASCII. So getopt has an
error message to an asprintf buffer, monkeys with internal flag bits
on stderr to disable cancellation, and then calls
__fxprintf(stderr, "%s", buffer). There isn't even a helper function,
the code is duplicated every time.
This patch fixes __fxprintf to handle arbitrary multibyte format
strings, and adds a variant __fxprintf_nocancel that does the same
thing but also isn't a cancellation point. (It still _works_ by
monkeying with internal flag bits on the FILE, but that's not really a
layering violation for code in stdio-common.) All of the #ifdef _LIBC
blocks can then be reduced to their standalone versions with a little
help from some macros at the top of the file.
I also wrote a test case to verify that getopt really isn't a
cancellation point, and I'm glad I did, because it found two bugs, one
of which wasn't even to do with cancellation (see previous patch).
* stdio-common/fxprintf.c (__fxprintf_nocancel): New function.
(locked_vfxprintf): New helper function. Handle arbitrary
multibyte strings, not just ASCII.
* include/stdio.h: Declare __fxprintf_nocancel.
* posix/getopt.c: When _LIBC is defined, define fprintf to
__fxprintf_nocancel, flockfile to _IO_flockfile, and
funlockfile to _IO_funlockfile. When neither _LIBC nor
_POSIX_THREAD_SAFE_FUNCTIONS is defined, define flockfile and
funlockfile as no-ops. (_getopt_internal_r): Remove all
internal #ifdef _LIBC blocks; the standalone error-printing
code can now be used for libc as well. Add an
flockfile/funlockfile pair around one case where the error
message is printed in several chunks. Don't use fputc.
* posix/tst-getopt-cancel.c: New test.
* posix/Makefile: Run it.
2017-04-01 22:17:44 +08:00
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#include <wchar.h>
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2005-08-09 04:06:29 +08:00
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#include <libioP.h>
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2005-07-20 07:46:55 +08:00
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getopt: clean up error reporting
getopt can print a whole bunch of error messages, and when used
standalone (from gnulib) it uses fprintf to do that. But fprintf is a
cancellation point and getopt isn't, and also applying fprintf to a
stream in wide-character mode is not allowed.
glibc has an internal function called __fxprintf that writes a narrow
format string to a stream regardless of mode, but it only handles
ASCII format strings, and it's still a cancellation point. getopt's
messages are translated, so they might not be ASCII. So getopt has an
error message to an asprintf buffer, monkeys with internal flag bits
on stderr to disable cancellation, and then calls
__fxprintf(stderr, "%s", buffer). There isn't even a helper function,
the code is duplicated every time.
This patch fixes __fxprintf to handle arbitrary multibyte format
strings, and adds a variant __fxprintf_nocancel that does the same
thing but also isn't a cancellation point. (It still _works_ by
monkeying with internal flag bits on the FILE, but that's not really a
layering violation for code in stdio-common.) All of the #ifdef _LIBC
blocks can then be reduced to their standalone versions with a little
help from some macros at the top of the file.
I also wrote a test case to verify that getopt really isn't a
cancellation point, and I'm glad I did, because it found two bugs, one
of which wasn't even to do with cancellation (see previous patch).
* stdio-common/fxprintf.c (__fxprintf_nocancel): New function.
(locked_vfxprintf): New helper function. Handle arbitrary
multibyte strings, not just ASCII.
* include/stdio.h: Declare __fxprintf_nocancel.
* posix/getopt.c: When _LIBC is defined, define fprintf to
__fxprintf_nocancel, flockfile to _IO_flockfile, and
funlockfile to _IO_funlockfile. When neither _LIBC nor
_POSIX_THREAD_SAFE_FUNCTIONS is defined, define flockfile and
funlockfile as no-ops. (_getopt_internal_r): Remove all
internal #ifdef _LIBC blocks; the standalone error-printing
code can now be used for libc as well. Add an
flockfile/funlockfile pair around one case where the error
message is printed in several chunks. Don't use fputc.
* posix/tst-getopt-cancel.c: New test.
* posix/Makefile: Run it.
2017-04-01 22:17:44 +08:00
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static int
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locked_vfxprintf (FILE *fp, const char *fmt, va_list ap)
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{
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if (_IO_fwide (fp, 0) <= 0)
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Add __v*printf_internal with flags arguments
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.
2018-03-08 03:32:01 +08:00
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return __vfprintf_internal (fp, fmt, ap, 0);
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getopt: clean up error reporting
getopt can print a whole bunch of error messages, and when used
standalone (from gnulib) it uses fprintf to do that. But fprintf is a
cancellation point and getopt isn't, and also applying fprintf to a
stream in wide-character mode is not allowed.
glibc has an internal function called __fxprintf that writes a narrow
format string to a stream regardless of mode, but it only handles
ASCII format strings, and it's still a cancellation point. getopt's
messages are translated, so they might not be ASCII. So getopt has an
error message to an asprintf buffer, monkeys with internal flag bits
on stderr to disable cancellation, and then calls
__fxprintf(stderr, "%s", buffer). There isn't even a helper function,
the code is duplicated every time.
This patch fixes __fxprintf to handle arbitrary multibyte format
strings, and adds a variant __fxprintf_nocancel that does the same
thing but also isn't a cancellation point. (It still _works_ by
monkeying with internal flag bits on the FILE, but that's not really a
layering violation for code in stdio-common.) All of the #ifdef _LIBC
blocks can then be reduced to their standalone versions with a little
help from some macros at the top of the file.
I also wrote a test case to verify that getopt really isn't a
cancellation point, and I'm glad I did, because it found two bugs, one
of which wasn't even to do with cancellation (see previous patch).
* stdio-common/fxprintf.c (__fxprintf_nocancel): New function.
(locked_vfxprintf): New helper function. Handle arbitrary
multibyte strings, not just ASCII.
* include/stdio.h: Declare __fxprintf_nocancel.
* posix/getopt.c: When _LIBC is defined, define fprintf to
__fxprintf_nocancel, flockfile to _IO_flockfile, and
funlockfile to _IO_funlockfile. When neither _LIBC nor
_POSIX_THREAD_SAFE_FUNCTIONS is defined, define flockfile and
funlockfile as no-ops. (_getopt_internal_r): Remove all
internal #ifdef _LIBC blocks; the standalone error-printing
code can now be used for libc as well. Add an
flockfile/funlockfile pair around one case where the error
message is printed in several chunks. Don't use fputc.
* posix/tst-getopt-cancel.c: New test.
* posix/Makefile: Run it.
2017-04-01 22:17:44 +08:00
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/* We must convert the narrow format string to a wide one.
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Each byte can produce at most one wide character. */
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wchar_t *wfmt;
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mbstate_t mbstate;
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int res;
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int used_malloc = 0;
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size_t len = strlen (fmt) + 1;
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if (__glibc_unlikely (len > SIZE_MAX / sizeof (wchar_t)))
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{
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__set_errno (EOVERFLOW);
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return -1;
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}
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if (__libc_use_alloca (len * sizeof (wchar_t)))
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wfmt = alloca (len * sizeof (wchar_t));
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else if ((wfmt = malloc (len * sizeof (wchar_t))) == NULL)
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return -1;
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else
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used_malloc = 1;
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memset (&mbstate, 0, sizeof mbstate);
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res = __mbsrtowcs (wfmt, &fmt, len, &mbstate);
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if (res != -1)
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Add __v*printf_internal with flags arguments
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.
2018-03-08 03:32:01 +08:00
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res = __vfwprintf_internal (fp, wfmt, ap, 0);
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getopt: clean up error reporting
getopt can print a whole bunch of error messages, and when used
standalone (from gnulib) it uses fprintf to do that. But fprintf is a
cancellation point and getopt isn't, and also applying fprintf to a
stream in wide-character mode is not allowed.
glibc has an internal function called __fxprintf that writes a narrow
format string to a stream regardless of mode, but it only handles
ASCII format strings, and it's still a cancellation point. getopt's
messages are translated, so they might not be ASCII. So getopt has an
error message to an asprintf buffer, monkeys with internal flag bits
on stderr to disable cancellation, and then calls
__fxprintf(stderr, "%s", buffer). There isn't even a helper function,
the code is duplicated every time.
This patch fixes __fxprintf to handle arbitrary multibyte format
strings, and adds a variant __fxprintf_nocancel that does the same
thing but also isn't a cancellation point. (It still _works_ by
monkeying with internal flag bits on the FILE, but that's not really a
layering violation for code in stdio-common.) All of the #ifdef _LIBC
blocks can then be reduced to their standalone versions with a little
help from some macros at the top of the file.
I also wrote a test case to verify that getopt really isn't a
cancellation point, and I'm glad I did, because it found two bugs, one
of which wasn't even to do with cancellation (see previous patch).
* stdio-common/fxprintf.c (__fxprintf_nocancel): New function.
(locked_vfxprintf): New helper function. Handle arbitrary
multibyte strings, not just ASCII.
* include/stdio.h: Declare __fxprintf_nocancel.
* posix/getopt.c: When _LIBC is defined, define fprintf to
__fxprintf_nocancel, flockfile to _IO_flockfile, and
funlockfile to _IO_funlockfile. When neither _LIBC nor
_POSIX_THREAD_SAFE_FUNCTIONS is defined, define flockfile and
funlockfile as no-ops. (_getopt_internal_r): Remove all
internal #ifdef _LIBC blocks; the standalone error-printing
code can now be used for libc as well. Add an
flockfile/funlockfile pair around one case where the error
message is printed in several chunks. Don't use fputc.
* posix/tst-getopt-cancel.c: New test.
* posix/Makefile: Run it.
2017-04-01 22:17:44 +08:00
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if (used_malloc)
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free (wfmt);
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return res;
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}
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2005-07-20 07:46:55 +08:00
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int
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2018-08-14 19:36:10 +08:00
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__vfxprintf (FILE *fp, const char *fmt, va_list ap)
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2005-07-20 07:46:55 +08:00
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{
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if (fp == NULL)
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fp = stderr;
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getopt: clean up error reporting
getopt can print a whole bunch of error messages, and when used
standalone (from gnulib) it uses fprintf to do that. But fprintf is a
cancellation point and getopt isn't, and also applying fprintf to a
stream in wide-character mode is not allowed.
glibc has an internal function called __fxprintf that writes a narrow
format string to a stream regardless of mode, but it only handles
ASCII format strings, and it's still a cancellation point. getopt's
messages are translated, so they might not be ASCII. So getopt has an
error message to an asprintf buffer, monkeys with internal flag bits
on stderr to disable cancellation, and then calls
__fxprintf(stderr, "%s", buffer). There isn't even a helper function,
the code is duplicated every time.
This patch fixes __fxprintf to handle arbitrary multibyte format
strings, and adds a variant __fxprintf_nocancel that does the same
thing but also isn't a cancellation point. (It still _works_ by
monkeying with internal flag bits on the FILE, but that's not really a
layering violation for code in stdio-common.) All of the #ifdef _LIBC
blocks can then be reduced to their standalone versions with a little
help from some macros at the top of the file.
I also wrote a test case to verify that getopt really isn't a
cancellation point, and I'm glad I did, because it found two bugs, one
of which wasn't even to do with cancellation (see previous patch).
* stdio-common/fxprintf.c (__fxprintf_nocancel): New function.
(locked_vfxprintf): New helper function. Handle arbitrary
multibyte strings, not just ASCII.
* include/stdio.h: Declare __fxprintf_nocancel.
* posix/getopt.c: When _LIBC is defined, define fprintf to
__fxprintf_nocancel, flockfile to _IO_flockfile, and
funlockfile to _IO_funlockfile. When neither _LIBC nor
_POSIX_THREAD_SAFE_FUNCTIONS is defined, define flockfile and
funlockfile as no-ops. (_getopt_internal_r): Remove all
internal #ifdef _LIBC blocks; the standalone error-printing
code can now be used for libc as well. Add an
flockfile/funlockfile pair around one case where the error
message is printed in several chunks. Don't use fputc.
* posix/tst-getopt-cancel.c: New test.
* posix/Makefile: Run it.
2017-04-01 22:17:44 +08:00
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_IO_flockfile (fp);
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int res = locked_vfxprintf (fp, fmt, ap);
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_IO_funlockfile (fp);
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2018-08-14 19:36:10 +08:00
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return res;
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}
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int
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__fxprintf (FILE *fp, const char *fmt, ...)
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{
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va_list ap;
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va_start (ap, fmt);
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int res = __vfxprintf (fp, fmt, ap);
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2005-07-20 07:46:55 +08:00
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va_end (ap);
|
getopt: clean up error reporting
getopt can print a whole bunch of error messages, and when used
standalone (from gnulib) it uses fprintf to do that. But fprintf is a
cancellation point and getopt isn't, and also applying fprintf to a
stream in wide-character mode is not allowed.
glibc has an internal function called __fxprintf that writes a narrow
format string to a stream regardless of mode, but it only handles
ASCII format strings, and it's still a cancellation point. getopt's
messages are translated, so they might not be ASCII. So getopt has an
error message to an asprintf buffer, monkeys with internal flag bits
on stderr to disable cancellation, and then calls
__fxprintf(stderr, "%s", buffer). There isn't even a helper function,
the code is duplicated every time.
This patch fixes __fxprintf to handle arbitrary multibyte format
strings, and adds a variant __fxprintf_nocancel that does the same
thing but also isn't a cancellation point. (It still _works_ by
monkeying with internal flag bits on the FILE, but that's not really a
layering violation for code in stdio-common.) All of the #ifdef _LIBC
blocks can then be reduced to their standalone versions with a little
help from some macros at the top of the file.
I also wrote a test case to verify that getopt really isn't a
cancellation point, and I'm glad I did, because it found two bugs, one
of which wasn't even to do with cancellation (see previous patch).
* stdio-common/fxprintf.c (__fxprintf_nocancel): New function.
(locked_vfxprintf): New helper function. Handle arbitrary
multibyte strings, not just ASCII.
* include/stdio.h: Declare __fxprintf_nocancel.
* posix/getopt.c: When _LIBC is defined, define fprintf to
__fxprintf_nocancel, flockfile to _IO_flockfile, and
funlockfile to _IO_funlockfile. When neither _LIBC nor
_POSIX_THREAD_SAFE_FUNCTIONS is defined, define flockfile and
funlockfile as no-ops. (_getopt_internal_r): Remove all
internal #ifdef _LIBC blocks; the standalone error-printing
code can now be used for libc as well. Add an
flockfile/funlockfile pair around one case where the error
message is printed in several chunks. Don't use fputc.
* posix/tst-getopt-cancel.c: New test.
* posix/Makefile: Run it.
2017-04-01 22:17:44 +08:00
|
|
|
return res;
|
|
|
|
|
}
|
2005-07-20 07:46:55 +08:00
|
|
|
|
getopt: clean up error reporting
getopt can print a whole bunch of error messages, and when used
standalone (from gnulib) it uses fprintf to do that. But fprintf is a
cancellation point and getopt isn't, and also applying fprintf to a
stream in wide-character mode is not allowed.
glibc has an internal function called __fxprintf that writes a narrow
format string to a stream regardless of mode, but it only handles
ASCII format strings, and it's still a cancellation point. getopt's
messages are translated, so they might not be ASCII. So getopt has an
error message to an asprintf buffer, monkeys with internal flag bits
on stderr to disable cancellation, and then calls
__fxprintf(stderr, "%s", buffer). There isn't even a helper function,
the code is duplicated every time.
This patch fixes __fxprintf to handle arbitrary multibyte format
strings, and adds a variant __fxprintf_nocancel that does the same
thing but also isn't a cancellation point. (It still _works_ by
monkeying with internal flag bits on the FILE, but that's not really a
layering violation for code in stdio-common.) All of the #ifdef _LIBC
blocks can then be reduced to their standalone versions with a little
help from some macros at the top of the file.
I also wrote a test case to verify that getopt really isn't a
cancellation point, and I'm glad I did, because it found two bugs, one
of which wasn't even to do with cancellation (see previous patch).
* stdio-common/fxprintf.c (__fxprintf_nocancel): New function.
(locked_vfxprintf): New helper function. Handle arbitrary
multibyte strings, not just ASCII.
* include/stdio.h: Declare __fxprintf_nocancel.
* posix/getopt.c: When _LIBC is defined, define fprintf to
__fxprintf_nocancel, flockfile to _IO_flockfile, and
funlockfile to _IO_funlockfile. When neither _LIBC nor
_POSIX_THREAD_SAFE_FUNCTIONS is defined, define flockfile and
funlockfile as no-ops. (_getopt_internal_r): Remove all
internal #ifdef _LIBC blocks; the standalone error-printing
code can now be used for libc as well. Add an
flockfile/funlockfile pair around one case where the error
message is printed in several chunks. Don't use fputc.
* posix/tst-getopt-cancel.c: New test.
* posix/Makefile: Run it.
2017-04-01 22:17:44 +08:00
|
|
|
int
|
|
|
|
|
__fxprintf_nocancel (FILE *fp, const char *fmt, ...)
|
|
|
|
|
{
|
|
|
|
|
if (fp == NULL)
|
|
|
|
|
fp = stderr;
|
|
|
|
|
|
|
|
|
|
va_list ap;
|
|
|
|
|
va_start (ap, fmt);
|
|
|
|
|
_IO_flockfile (fp);
|
2018-02-08 07:42:04 +08:00
|
|
|
int save_flags2 = fp->_flags2;
|
|
|
|
|
fp->_flags2 |= _IO_FLAGS2_NOTCANCEL;
|
getopt: clean up error reporting
getopt can print a whole bunch of error messages, and when used
standalone (from gnulib) it uses fprintf to do that. But fprintf is a
cancellation point and getopt isn't, and also applying fprintf to a
stream in wide-character mode is not allowed.
glibc has an internal function called __fxprintf that writes a narrow
format string to a stream regardless of mode, but it only handles
ASCII format strings, and it's still a cancellation point. getopt's
messages are translated, so they might not be ASCII. So getopt has an
error message to an asprintf buffer, monkeys with internal flag bits
on stderr to disable cancellation, and then calls
__fxprintf(stderr, "%s", buffer). There isn't even a helper function,
the code is duplicated every time.
This patch fixes __fxprintf to handle arbitrary multibyte format
strings, and adds a variant __fxprintf_nocancel that does the same
thing but also isn't a cancellation point. (It still _works_ by
monkeying with internal flag bits on the FILE, but that's not really a
layering violation for code in stdio-common.) All of the #ifdef _LIBC
blocks can then be reduced to their standalone versions with a little
help from some macros at the top of the file.
I also wrote a test case to verify that getopt really isn't a
cancellation point, and I'm glad I did, because it found two bugs, one
of which wasn't even to do with cancellation (see previous patch).
* stdio-common/fxprintf.c (__fxprintf_nocancel): New function.
(locked_vfxprintf): New helper function. Handle arbitrary
multibyte strings, not just ASCII.
* include/stdio.h: Declare __fxprintf_nocancel.
* posix/getopt.c: When _LIBC is defined, define fprintf to
__fxprintf_nocancel, flockfile to _IO_flockfile, and
funlockfile to _IO_funlockfile. When neither _LIBC nor
_POSIX_THREAD_SAFE_FUNCTIONS is defined, define flockfile and
funlockfile as no-ops. (_getopt_internal_r): Remove all
internal #ifdef _LIBC blocks; the standalone error-printing
code can now be used for libc as well. Add an
flockfile/funlockfile pair around one case where the error
message is printed in several chunks. Don't use fputc.
* posix/tst-getopt-cancel.c: New test.
* posix/Makefile: Run it.
2017-04-01 22:17:44 +08:00
|
|
|
|
|
|
|
|
int res = locked_vfxprintf (fp, fmt, ap);
|
|
|
|
|
|
2018-02-08 07:42:04 +08:00
|
|
|
fp->_flags2 = save_flags2;
|
getopt: clean up error reporting
getopt can print a whole bunch of error messages, and when used
standalone (from gnulib) it uses fprintf to do that. But fprintf is a
cancellation point and getopt isn't, and also applying fprintf to a
stream in wide-character mode is not allowed.
glibc has an internal function called __fxprintf that writes a narrow
format string to a stream regardless of mode, but it only handles
ASCII format strings, and it's still a cancellation point. getopt's
messages are translated, so they might not be ASCII. So getopt has an
error message to an asprintf buffer, monkeys with internal flag bits
on stderr to disable cancellation, and then calls
__fxprintf(stderr, "%s", buffer). There isn't even a helper function,
the code is duplicated every time.
This patch fixes __fxprintf to handle arbitrary multibyte format
strings, and adds a variant __fxprintf_nocancel that does the same
thing but also isn't a cancellation point. (It still _works_ by
monkeying with internal flag bits on the FILE, but that's not really a
layering violation for code in stdio-common.) All of the #ifdef _LIBC
blocks can then be reduced to their standalone versions with a little
help from some macros at the top of the file.
I also wrote a test case to verify that getopt really isn't a
cancellation point, and I'm glad I did, because it found two bugs, one
of which wasn't even to do with cancellation (see previous patch).
* stdio-common/fxprintf.c (__fxprintf_nocancel): New function.
(locked_vfxprintf): New helper function. Handle arbitrary
multibyte strings, not just ASCII.
* include/stdio.h: Declare __fxprintf_nocancel.
* posix/getopt.c: When _LIBC is defined, define fprintf to
__fxprintf_nocancel, flockfile to _IO_flockfile, and
funlockfile to _IO_funlockfile. When neither _LIBC nor
_POSIX_THREAD_SAFE_FUNCTIONS is defined, define flockfile and
funlockfile as no-ops. (_getopt_internal_r): Remove all
internal #ifdef _LIBC blocks; the standalone error-printing
code can now be used for libc as well. Add an
flockfile/funlockfile pair around one case where the error
message is printed in several chunks. Don't use fputc.
* posix/tst-getopt-cancel.c: New test.
* posix/Makefile: Run it.
2017-04-01 22:17:44 +08:00
|
|
|
_IO_funlockfile (fp);
|
|
|
|
|
va_end (ap);
|
2005-07-20 07:46:55 +08:00
|
|
|
return res;
|
|
|
|
|
}
|
