1 /* Setup of nscd worker threads. Linux version.
2 Copyright (C) 2004-2024 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, see <https://www.gnu.org/licenses/>. */
25 setup_thread (struct database_dyn
*db
)
27 /* Only supported when NPTL is used. */
29 if (confstr (_CS_GNU_LIBPTHREAD_VERSION
, buf
, sizeof (buf
)) >= sizeof (buf
)
30 || strncmp (buf
, "NPTL", 4) != 0)
33 /* Do not try this at home, kids. We play with the SETTID address
34 even thought the process is multi-threaded. This can only work
35 since none of the threads ever terminates. */
36 int r
= INTERNAL_SYSCALL_CALL (set_tid_address
,
37 &db
->head
->nscd_certainly_running
);
38 if (!INTERNAL_SYSCALL_ERROR_P (r
))
39 /* We know the kernel can reset this field when nscd terminates.
40 So, set the field to a nonzero value which indicates that nscd
41 is certainly running and clients can skip the test. */
42 return db
->head
->nscd_certainly_running
= 1;