glibc/stdio-common/vfwscanf.c

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Add __vfscanf_internal and __vfwscanf_internal with flags arguments. There are two flags currently defined: SCANF_LDBL_IS_DBL is the mode used by __nldbl_ scanf variants, and SCANF_ISOC99_A is the mode used by __isoc99_ scanf variants. In this patch, the new functions honor these flag bits if they're set, but they still also look at the corresponding bits of environmental state, and callers all pass zero. The new functions do *not* have the "errp" argument possessed by _IO_vfscanf and _IO_vfwscanf. All internal callers passed NULL for that argument. External callers could theoretically exist, so I preserved wrappers, but they are flagged as compat symbols and they don't preserve the three-way distinction among types of errors that was formerly exposed. These functions probably should have been in the list of deprecated _IO_ symbols in 2.27 NEWS -- they're not just aliases for vfscanf and vfwscanf. (It was necessary to introduce ldbl_compat_symbol for _IO_vfscanf. Please check that part of the patch very carefully, I am still not confident I understand all of the details of ldbl-opt.) This patch also introduces helper inlines in libio/strfile.h that encapsulate the process of initializing an _IO_strfile object for reading. This allows us to call __vfscanf_internal directly from sscanf, and __vfwscanf_internal directly from swscanf, without duplicating the initialization code. (Previously, they called their v-counterparts, but that won't work if we want to control *both* C99 mode and ldbl-is-dbl mode using the flags argument to__vfscanf_internal.) It's still a little awkward, especially for wide strfiles, but it's much better than what we had. Tested for powerpc and powerpc64le.
2018-03-07 19:31:58 +00:00
/* Implementation and symbols for vfwscanf.
Copyright (C) 2018-2024 Free Software Foundation, Inc.
Add __vfscanf_internal and __vfwscanf_internal with flags arguments. There are two flags currently defined: SCANF_LDBL_IS_DBL is the mode used by __nldbl_ scanf variants, and SCANF_ISOC99_A is the mode used by __isoc99_ scanf variants. In this patch, the new functions honor these flag bits if they're set, but they still also look at the corresponding bits of environmental state, and callers all pass zero. The new functions do *not* have the "errp" argument possessed by _IO_vfscanf and _IO_vfwscanf. All internal callers passed NULL for that argument. External callers could theoretically exist, so I preserved wrappers, but they are flagged as compat symbols and they don't preserve the three-way distinction among types of errors that was formerly exposed. These functions probably should have been in the list of deprecated _IO_ symbols in 2.27 NEWS -- they're not just aliases for vfscanf and vfwscanf. (It was necessary to introduce ldbl_compat_symbol for _IO_vfscanf. Please check that part of the patch very carefully, I am still not confident I understand all of the details of ldbl-opt.) This patch also introduces helper inlines in libio/strfile.h that encapsulate the process of initializing an _IO_strfile object for reading. This allows us to call __vfscanf_internal directly from sscanf, and __vfwscanf_internal directly from swscanf, without duplicating the initialization code. (Previously, they called their v-counterparts, but that won't work if we want to control *both* C99 mode and ldbl-is-dbl mode using the flags argument to__vfscanf_internal.) It's still a little awkward, especially for wide strfiles, but it's much better than what we had. Tested for powerpc and powerpc64le.
2018-03-07 19:31:58 +00:00
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, see
Prefer https to http for gnu.org and fsf.org URLs Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-09-07 05:40:42 +00:00
<https://www.gnu.org/licenses/>. */
Add __vfscanf_internal and __vfwscanf_internal with flags arguments. There are two flags currently defined: SCANF_LDBL_IS_DBL is the mode used by __nldbl_ scanf variants, and SCANF_ISOC99_A is the mode used by __isoc99_ scanf variants. In this patch, the new functions honor these flag bits if they're set, but they still also look at the corresponding bits of environmental state, and callers all pass zero. The new functions do *not* have the "errp" argument possessed by _IO_vfscanf and _IO_vfwscanf. All internal callers passed NULL for that argument. External callers could theoretically exist, so I preserved wrappers, but they are flagged as compat symbols and they don't preserve the three-way distinction among types of errors that was formerly exposed. These functions probably should have been in the list of deprecated _IO_ symbols in 2.27 NEWS -- they're not just aliases for vfscanf and vfwscanf. (It was necessary to introduce ldbl_compat_symbol for _IO_vfscanf. Please check that part of the patch very carefully, I am still not confident I understand all of the details of ldbl-opt.) This patch also introduces helper inlines in libio/strfile.h that encapsulate the process of initializing an _IO_strfile object for reading. This allows us to call __vfscanf_internal directly from sscanf, and __vfwscanf_internal directly from swscanf, without duplicating the initialization code. (Previously, they called their v-counterparts, but that won't work if we want to control *both* C99 mode and ldbl-is-dbl mode using the flags argument to__vfscanf_internal.) It's still a little awkward, especially for wide strfiles, but it's much better than what we had. Tested for powerpc and powerpc64le.
2018-03-07 19:31:58 +00:00
Use C99-compliant scanf under _GNU_SOURCE with modern compilers. The only difference between noncompliant and C99-compliant scanf is that the former accepts the archaic GNU extension '%as' (also %aS and %a[...]) meaning to allocate space for the input string with malloc. This extension conflicts with C99's use of %a as a format _type_ meaning to read a floating-point number; POSIX.1-2008 standardized equivalent functionality using the modifier letter 'm' instead (%ms, %mS, %m[...]). The extension was already disabled in most conformance modes: specifically, any mode that doesn't involve _GNU_SOURCE and _does_ involve either strict conformance to C99 or loose conformance to both C99 and POSIX.1-2001 would get the C99-compliant scanf. With compilers new enough to use -std=gnu11 instead of -std=gnu89, or equivalent, that includes the default mode. With this patch, we now provide C99-compliant scanf in all configurations except when _GNU_SOURCE is defined *and* __STDC_VERSION__ or __cplusplus (whichever is relevant) indicates C89/C++98. This leaves the old scanf available under e.g. -std=c89 -D_GNU_SOURCE, but removes it from e.g. -std=gnu11 -D_GNU_SOURCE (it was already not present under -std=gnu11 without -D_GNU_SOURCE) and from -std=gnu89 without -D_GNU_SOURCE. There needs to be an internal override so we can compile the noncompliant scanf itself. This is the same problem we had when we removed 'gets' from _GNU_SOURCE and it's dealt with the same way: there's a new __GLIBC_USE symbol, DEPRECATED_SCANF, which defaults to off under the appropriate conditions for external code, but can be overridden by individual files within stdio. We also run into problems with PLT bypass for internal uses of sscanf, because libc_hidden_proto uses __REDIRECT and so does the logic in stdio.h for choosing which implementation of scanf to use; __REDIRECT isn't transitive, so include/stdio.h needs to bridge the gap with a macro. As far as I can tell, sscanf is the only function in this family that's internally called by unrelated code. Finally, there are several tests in stdio-common that use the extension. bug21.c is a regression test for a crash; it still exercises the relevant code when changed to use %ms instead of %as. scanf14.c through scanf17.c are more complicated since they are actually testing the subtleties of the extension - under what circumstances is 'a' treated as a modifier letter, etc. I changed all of them to use %ms instead of %as as well, but duplicated scanf14.c and scanf16.c as scanf14a.c and scanf16a.c. These still use %as and are compiled with -std=gnu89 to access the old extension. A bunch of diagnostic overrides and manual workarounds for the old stdio.h behavior become unnecessary. Yay! * include/features.h (__GLIBC_USE_DEPRECATED_SCANF): New __GLIBC_USE parameter. Only use deprecated scanf when __USE_GNU is defined and __STDC_VERSION__ is less than 199901L or __cplusplus is less than 201103L, whichever is relevant for the language being compiled. * libio/stdio.h, libio/bits/stdio-ldbl.h: Decide whether to redirect scanf, fscanf, sscanf, vscanf, vfscanf, and vsscanf to their __isoc99_ variants based only on __GLIBC_USE (DEPRECATED_SCANF). * wcsmbs/wchar.h: wcsmbs/bits/wchar-ldbl.h: Likewise for wscanf, fwscanf, swscanf, vwscanf, vfwscanf, and vswscanf. * libio/iovsscanf.c * libio/fwscanf.c * libio/iovswscanf.c * libio/swscanf.c * libio/vscanf.c * libio/vwscanf.c * libio/wscanf.c * stdio-common/fscanf.c * stdio-common/scanf.c * stdio-common/vfscanf.c * stdio-common/vfwscanf.c * sysdeps/ieee754/ldbl-opt/nldbl-compat.c * sysdeps/ieee754/ldbl-opt/nldbl-fscanf.c * sysdeps/ieee754/ldbl-opt/nldbl-fwscanf.c * sysdeps/ieee754/ldbl-opt/nldbl-iovfscanf.c * sysdeps/ieee754/ldbl-opt/nldbl-scanf.c * sysdeps/ieee754/ldbl-opt/nldbl-sscanf.c * sysdeps/ieee754/ldbl-opt/nldbl-swscanf.c * sysdeps/ieee754/ldbl-opt/nldbl-vfscanf.c * sysdeps/ieee754/ldbl-opt/nldbl-vfwscanf.c * sysdeps/ieee754/ldbl-opt/nldbl-vscanf.c * sysdeps/ieee754/ldbl-opt/nldbl-vsscanf.c * sysdeps/ieee754/ldbl-opt/nldbl-vswscanf.c * sysdeps/ieee754/ldbl-opt/nldbl-vwscanf.c * sysdeps/ieee754/ldbl-opt/nldbl-wscanf.c: Override __GLIBC_USE_DEPRECATED_SCANF to 1. * stdio-common/sscanf.c: Likewise. Remove ldbl_hidden_def for __sscanf. * stdio-common/isoc99_sscanf.c: Add libc_hidden_def for __isoc99_sscanf. * include/stdio.h: Provide libc_hidden_proto for __isoc99_sscanf, not sscanf. [!__GLIBC_USE (DEPRECATED_SCANF)]: Define sscanf as __isoc99_scanf with a preprocessor macro. * stdio-common/bug21.c, stdio-common/scanf14.c: Use %ms instead of %as, %mS instead of %aS, %m[] instead of %a[]; remove DIAG_IGNORE_NEEDS_COMMENT for -Wformat. * stdio-common/scanf16.c: Likewise. Add __attribute__ ((format (scanf))) to xscanf, xfscanf, xsscanf. * stdio-common/scanf14a.c: New copy of scanf14.c which still uses %as, %aS, %a[]. Remove DIAG_IGNORE_NEEDS_COMMENT for -Wformat. * stdio-common/scanf16a.c: New copy of scanf16.c which still uses %as, %aS, %a[]. Add __attribute__ ((format (scanf))) to xscanf, xfscanf, xsscanf. * stdio-common/scanf15.c, stdio-common/scanf17.c: No need to override feature selection macros or provide definitions of u_char etc. * stdio-common/Makefile (tests): Add scanf14a and scanf16a. (CFLAGS-scanf15.c, CFLAGS-scanf17.c): Remove. (CFLAGS-scanf14a.c, CFLAGS-scanf16a.c): New. Compile these files with -std=gnu89.
2018-02-10 16:58:35 +00:00
/* This file defines one of the deprecated scanf variants. */
#include <features.h>
#undef __GLIBC_USE_DEPRECATED_SCANF
#define __GLIBC_USE_DEPRECATED_SCANF 1
Add __vfscanf_internal and __vfwscanf_internal with flags arguments. There are two flags currently defined: SCANF_LDBL_IS_DBL is the mode used by __nldbl_ scanf variants, and SCANF_ISOC99_A is the mode used by __isoc99_ scanf variants. In this patch, the new functions honor these flag bits if they're set, but they still also look at the corresponding bits of environmental state, and callers all pass zero. The new functions do *not* have the "errp" argument possessed by _IO_vfscanf and _IO_vfwscanf. All internal callers passed NULL for that argument. External callers could theoretically exist, so I preserved wrappers, but they are flagged as compat symbols and they don't preserve the three-way distinction among types of errors that was formerly exposed. These functions probably should have been in the list of deprecated _IO_ symbols in 2.27 NEWS -- they're not just aliases for vfscanf and vfwscanf. (It was necessary to introduce ldbl_compat_symbol for _IO_vfscanf. Please check that part of the patch very carefully, I am still not confident I understand all of the details of ldbl-opt.) This patch also introduces helper inlines in libio/strfile.h that encapsulate the process of initializing an _IO_strfile object for reading. This allows us to call __vfscanf_internal directly from sscanf, and __vfwscanf_internal directly from swscanf, without duplicating the initialization code. (Previously, they called their v-counterparts, but that won't work if we want to control *both* C99 mode and ldbl-is-dbl mode using the flags argument to__vfscanf_internal.) It's still a little awkward, especially for wide strfiles, but it's much better than what we had. Tested for powerpc and powerpc64le.
2018-03-07 19:31:58 +00:00
#include <libioP.h>
int
__vfwscanf (FILE *s, const wchar_t *format, va_list argptr)
{
return __vfwscanf_internal (s, format, argptr, 0);
}
ldbl_weak_alias (__vfwscanf, vfwscanf)