dd481ccffd
In <https://sourceware.org/ml/libc-alpha/2013-12/msg00008.html>, Aurelien noted issues with the definition of __ASSUME_ACCEPT4, which I discussed in more detail in <https://sourceware.org/ml/libc-alpha/2013-12/msg00014.html>; these are now bug 16609. As previously noted, __ASSUME_ACCEPT4 is used in two ways: * In OS-independent code, to mean "accept4 can be assumed to work rather than fail with ENOSYS". It doesn't matter whether it's implemented with socketcall or a separate syscall. * In Linux-specific code, to mean "the socketcall multiplex syscall can be assumed to handle the accept4 operation. When used in Linux-specific code, it *never* refers to anything relating to the accept4 syscall, only to the socketcall multiplexer. This patch splits the macro into separate __ASSUME_ACCEPT4_SOCKETCALL, __ASSUME_ACCEPT4_SYSCALL and __ASSUME_ACCEPT4 to clarify the different cases involved. A macro __ASSUME_SOCKETCALL is added for convenience in writing logic relating to all socketcall architectures. In addition, to address the issue of architectures where socketcall support for accept4 was added before a separate syscall was added (and so the separate syscall should not be used unless known to be present or fallback to socketcall is available), a fourth macro __ASSUME_ACCEPT4_SYSCALL_WITH_SOCKETCALL is added to indicate that the syscall became available at the same time as socketcall support. This is then used in the relevant places in a conditional determining whether to undefine __NR_accept4 (the simple approach to avoiding the syscall's presence causing problems; I didn't try to implement runtime fallback from the syscall to socketcall). Architecture-specific note: alpha defined __ASSUME_ACCEPT4 for 2.6.33 and later, but actually the syscall was added for alpha in 3.2, so this patch uses the correct condition for __ASSUME_ACCEPT4_SYSCALL there. Tested x86_64, including that disassembly of the installed shared libraries is unchanged by this patch. [BZ #16609] * sysdeps/unix/sysv/linux/kernel-features.h [__i386__ || __powerpc__ || __s390__ || __sh__ || __sparc__] (__ASSUME_SOCKETCALL): Define. [__LINUX_KERNEL_VERSION && __ASSUME_SOCKETCALL] (__ASSUME_ACCEPT4_SOCKETCALL): Likewise. [(__LINUX_KERNEL_VERSION >= 0x02061c && (__x86_64__ || __sparc__)) || (__LINUX_KERNEL_VERSION >= 0x020625 && (__powerpc__ || __sh__))] (__ASSUME_ACCEPT4_SYSCALL): Likewise. [__sparc__] (__ASSUME_ACCEPT4_SYSCALL_WITH_SOCKETCALL): Likewise. [__ASSUME_ACCEPT4_SOCKETCALL || __ASSUME_ACCEPT4_SYSCALL] (__ASSUME_ACCEPT4): Define instead of using previous [__LINUX_KERNEL_VERSION >= 0x02061c && (__i386__ || __x86_64__ || __powerpc__ || __sparc__ || __s390__)] condition. * sysdeps/unix/sysv/linux/aarch64/kernel-features.h (__ASSUME_ACCEPT4): Change to __ASSUME_ACCEPT4_SYSCALL. * sysdeps/unix/sysv/linux/accept4.c [__ASSUME_SOCKETCALL && !__ASSUME_ACCEPT4_SYSCALL_WITH_SOCKETCALL && !__ASSUME_ACCEPT4_SYSCALL] (__NR_accept4): Undefine. [!__ASSUME_ACCEPT4]: Change condition to [!__ASSUME_ACCEPT4_SOCKETCALL]. * sysdeps/unix/sysv/linux/alpha/kernel-features.h (__ASSUME_ACCEPT4): Change to __ASSUME_ACCEPT4_SYSCALL. Correct condition to [__LINUX_KERNEL_VERSION >= 0x030200]. * sysdeps/unix/sysv/linux/arm/kernel-features.h [__LINUX_KERNEL_VERSION >= 0x020624] (__ASSUME_ACCEPT4): Change to __ASSUME_ACCEPT4_SYSCALL. * sysdeps/unix/sysv/linux/i386/accept4.S [__ASSUME_ACCEPT4]: Change conditions to [__ASSUME_ACCEPT4_SOCKETCALL]. * sysdeps/unix/sysv/linux/ia64/kernel-features.h [__LINUX_KERNEL_VERSION >= 0x030300] (__ASSUME_ACCEPT4): Change to __ASSUME_ACCEPT4_SYSCALL. * sysdeps/unix/sysv/linux/internal_accept4.S [__ASSUME_SOCKETCALL && !__ASSUME_ACCEPT4_SYSCALL_WITH_SOCKETCALL && !__ASSUME_ACCEPT4_SYSCALL] (__NR_accept4): Undefine. [__ASSUME_ACCEPT4]: Change condition to [__ASSUME_ACCEPT4_SOCKETCALL]. * sysdeps/unix/sysv/linux/m68k/kernel-features.h (__ASSUME_SOCKETCALL): Define. [__LINUX_KERNEL_VERSION >= 0x02061c] (__ASSUME_ACCEPT4): Remove. * sysdeps/unix/sysv/linux/microblaze/kernel-features.h (__ASSUME_SOCKETCALL): Define. (__ASSUME_ACCEPT4): Remove. [__LINUX_KERNEL_VERSION >= 0x020621] (__ASSUME_ACCEPT4_SYSCALL): Define. * sysdeps/unix/sysv/linux/mips/kernel-features.h [__LINUX_KERNEL_VERSION >= 0x02061f] (__ASSUME_ACCEPT4_SYSCALL): Likewise. * sysdeps/unix/sysv/linux/tile/kernel-features.h (__ASSUME_ACCEPT4): Change to __ASSUME_ACCEPT4_SYSCALL. * sysdeps/unix/sysv/linux/hppa/kernel-features.h [__LINUX_KERNEL_VERSION >= 0x020622] (__ASSUME_ACCEPT4_SYSCALL): Define.
46 lines
1.6 KiB
C
46 lines
1.6 KiB
C
/* Set flags signalling availability of kernel features based on given
|
|
kernel version number.
|
|
Copyright (C) 2006-2014 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, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
/* The utimes syscall was added before 2.6.1. */
|
|
#define __ASSUME_UTIMES 1
|
|
|
|
/* The signal frame layout changed in 2.6.18. */
|
|
#if __LINUX_KERNEL_VERSION >= 132626
|
|
# define __ASSUME_SIGFRAME_V2 1
|
|
#endif
|
|
|
|
/* Support for the eventfd2 and signalfd4 syscalls was added in 2.6.27. */
|
|
#if __LINUX_KERNEL_VERSION >= 0x02061b
|
|
# define __ASSUME_EVENTFD2 1
|
|
# define __ASSUME_SIGNALFD4 1
|
|
#endif
|
|
|
|
/* Support for the accept4 syscall was added in 2.6.36. */
|
|
#if __LINUX_KERNEL_VERSION >= 0x020624
|
|
# define __ASSUME_ACCEPT4_SYSCALL 1
|
|
#endif
|
|
|
|
#include_next <kernel-features.h>
|
|
|
|
/* Support for pselect6, ppoll and epoll_pwait was added in 2.6.32. */
|
|
#if __LINUX_KERNEL_VERSION < 0x020620
|
|
# undef __ASSUME_PSELECT
|
|
# undef __ASSUME_PPOLL
|
|
#endif
|