Joseph Myers dd481ccffd Fix __ASSUME_ACCEPT4 issues (bug 16609). ... 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.		2014-02-20 17:50:31 +00:00
..
linux	Fix __ASSUME_ACCEPT4 issues (bug 16609).	2014-02-20 17:50:31 +00:00