1/* Copyright (C) 2001-2022 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#ifndef _GAI_MISC_H
19#define _GAI_MISC_H 1
20
21#include <netdb.h>
22#include <signal.h>
23
24
25/* Used to synchronize. */
26struct waitlist
27 {
28 struct waitlist *next;
29
30#ifndef DONT_NEED_GAI_MISC_COND
31 pthread_cond_t *cond;
32#endif
33 volatile unsigned int *counterp;
34 /* The next field is used in asynchronous `lio_listio' operations. */
35 struct sigevent *sigevp;
36 /* XXX See requestlist, it's used to work around the broken signal
37 handling in Linux. */
38 pid_t caller_pid;
39 };
40
41
42/* Used to queue requests.. */
43struct requestlist
44 {
45 int running;
46
47 struct requestlist *next;
48
49 /* Pointer to the actual data. */
50 struct gaicb *gaicbp;
51
52 /* List of waiting processes. */
53 struct waitlist *waiting;
54 };
55
56/* To customize the implementation one can use the following struct.
57 This implementation follows the one in Irix. */
58struct gaiinit
59 {
60 int gai_threads; /* Maximal number of threads. */
61 int gai_num; /* Number of expected simultanious requests. */
62 int gai_locks; /* Not used. */
63 int gai_usedba; /* Not used. */
64 int gai_debug; /* Not used. */
65 int gai_numusers; /* Not used. */
66 int gai_idle_time; /* Number of seconds before idle thread
67 terminates. */
68 int gai_reserved;
69 };
70
71
72/* Lock for global I/O list of requests. */
73extern pthread_mutex_t __gai_requests_mutex;
74
75
76/* Enqueue request. */
77extern struct requestlist *__gai_enqueue_request (struct gaicb *gaicbp)
78 attribute_hidden;
79
80/* Find request on wait list. */
81extern struct requestlist *__gai_find_request (const struct gaicb *gaicbp)
82 attribute_hidden;
83
84/* Remove request from waitlist. */
85extern int __gai_remove_request (struct gaicb *gaicbp)
86 attribute_hidden;
87
88/* Notify initiator of request and tell this everybody listening. */
89extern void __gai_notify (struct requestlist *req)
90 attribute_hidden;
91
92/* Notify initiator of request. */
93extern int __gai_notify_only (struct sigevent *sigev, pid_t caller_pid)
94 attribute_hidden;
95
96/* Send the signal. */
97extern int __gai_sigqueue (int sig, const union sigval val, pid_t caller_pid);
98libc_hidden_proto (__gai_sigqueue)
99
100#endif /* gai_misc.h */
101

source code of glibc/resolv/gai_misc.h