diff options
Diffstat (limited to 'sysdeps/unix')
-rw-r--r-- | sysdeps/unix/sysv/linux/nscd_setup_thread.c | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/nscd_setup_thread.c b/sysdeps/unix/sysv/linux/nscd_setup_thread.c new file mode 100644 index 0000000000..3496f02dca --- /dev/null +++ b/sysdeps/unix/sysv/linux/nscd_setup_thread.c @@ -0,0 +1,47 @@ +/* Setup of nscd worker threads. Linux verison. + Copyright (C) 2004 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@redhat.com>, 2004. + + 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <string.h> +#include <unistd.h> +#include <nscd.h> +#include <sysdep.h> + + +void +setup_thread (struct database_dyn *db) +{ + /* Only supported when NPTL is used. */ + char buf[100]; + if (confstr (_CS_GNU_LIBPTHREAD_VERSION, buf, sizeof (buf)) >= sizeof (buf) + || strncmp (buf, "NPTL", 4) != 0) + return; + + /* Do not try this at home, kids. We play with the SETTID address + even thought the process is multi-threaded. This can only work + since none of the threads ever terminates. */ + INTERNAL_SYSCALL_DECL (err); + int r = INTERNAL_SYSCALL (set_tid_address, err, 1, + &db->head->nscd_certainly_running); + if (!INTERNAL_SYSCALL_ERROR_P (r, err)) + /* We know the kernel can reset this field when nscd terminates. + So, set the field to a nonzero value which indicates that nscd + is certainly running and clients can skip the test. */ + db->head->nscd_certainly_running = 1; +} |