0595c98494
mq_notify (in the 1996 edition of POSIX) brings in references to recv and socket (not in POSIX until the 2001 edition). This patch fixes this by using __recv and __socket, exporting them from libc at version GLIBC_PRIVATE. Tested for x86_64 and x86 (testsuite and comparison of installed stripped shared libraries; PLT / dynamic symbol table changes render the comparison not particularly useful for libc). [BZ #18546] * socket/recv.c (__recv): Use libc_hidden_def. * socket/socket.c (__socket): Likewise. * sysdeps/mach/hurd/recv.c (__recv): Likewise. * sysdeps/mach/hurd/socket.c (__socket): Likewise. * sysdeps/unix/sysv/linux/generic/recv.c (__recv): Likewise. * sysdeps/unix/sysv/linux/recv.c (__recv): Use libc_hidden_weak. * sysdeps/unix/sysv/linux/socket.c (__socket): Use libc_hidden_def. * sysdeps/unix/sysv/linux/x86_64/recv.c (__recv): Use libc_hidden_weak. * include/sys/socket.h (__socket): Do not use attribute_hidden. Use libc_hidden_proto. (__recv): Likewise. * socket/Versions (libc): Export __recv and __socket at version GLIBC_PRIVATE. * sysdeps/unix/sysv/linux/mq_notify.c (helper_thread): Call __recv instead of recv. (init_mq_netlink): Call __socket instead of socket. * conform/Makefile (test-xfail-POSIX/mqueue.h/linknamespace): Remove variable.
This hierarchy supports Linux systems using the new asm-generic/unistd.h, which removes many familiar old syscalls. For example, to implement open(), newer Linux architectures require glibc to invoke the __NR_openat syscall with AT_FDCWD. This hierarchy provides all those implementations. It also provides support for 32-bit platforms using the 64-bit kernel syscall APIs, as the 32-bit ones are no longer provided. Note that newer ILP32 environments (x32 or AArch64:ILP32, for example) are converting to use more 64-bit types in kernel syscalls, so that aspect of this support is in more flux as of this writing.