1 /* Copyright (C) 2001-2023 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 #include <errno.h>
19 #include <netdb.h>
20 #include <pthread.h>
21 #include <stdlib.h>
22 #include <sys/time.h>
23
24 #include <gai_misc.h>
25
26 int
27 ___gai_suspend_time64 (const struct gaicb *const list[], int ent,
28 const struct __timespec64 *timeout)
29 {
30 struct waitlist waitlist[ent];
31 struct requestlist *requestlist[ent];
32 #ifndef DONT_NEED_GAI_MISC_COND
33 pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
34 #endif
35 int cnt;
36 unsigned int cntr = 1;
37 int none = 1;
38 int result;
39
40 /* Request the mutex. */
41 __pthread_mutex_lock (&__gai_requests_mutex);
42
43 /* There is not yet a finished request. Signal the request that
44 we are working for it. */
45 for (cnt = 0; cnt < ent; ++cnt)
46 if (list[cnt] != NULL && list[cnt]->__return == EAI_INPROGRESS)
47 {
48 requestlist[cnt] = __gai_find_request (list[cnt]);
49
50 if (requestlist[cnt] != NULL)
51 {
52 #ifndef DONT_NEED_GAI_MISC_COND
53 waitlist[cnt].cond = &cond;
54 #endif
55 waitlist[cnt].next = requestlist[cnt]->waiting;
56 waitlist[cnt].counterp = &cntr;
57 waitlist[cnt].sigevp = NULL;
58 waitlist[cnt].caller_pid = 0; /* Not needed. */
59 requestlist[cnt]->waiting = &waitlist[cnt];
60 none = 0;
61 }
62 }
63
64 struct __timespec64 ts;
65 if (timeout != NULL)
66 {
67 __clock_gettime64 (CLOCK_MONOTONIC, &ts);
68 ts.tv_sec += timeout->tv_sec;
69 ts.tv_nsec += timeout->tv_nsec;
70 if (ts.tv_nsec >= 1000000000)
71 {
72 ts.tv_nsec -= 1000000000;
73 ts.tv_sec++;
74 }
75 }
76
77 if (none)
78 {
79 if (cnt < ent)
80 /* There is an entry which is finished. */
81 result = 0;
82 else
83 result = EAI_ALLDONE;
84 }
85 else
86 {
87 /* There is no request done but some are still being worked on. */
88 int oldstate;
89
90 /* Since `pthread_cond_wait'/`pthread_cond_timedwait' are cancelation
91 points we must be careful. We added entries to the waiting lists
92 which we must remove. So defer cancelation for now. */
93 __pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, &oldstate);
94
95 #ifdef DONT_NEED_GAI_MISC_COND
96 result = 0;
97 GAI_MISC_WAIT (result, cntr, timeout == NULL ? NULL : &ts, 1);
98 #else
99 struct timespec ts32 = valid_timespec64_to_timespec (ts);
100 result = pthread_cond_timedwait (&cond, &__gai_requests_mutex,
101 timeout == NULL ? NULL : &ts32);
102 #endif
103
104 /* Now remove the entry in the waiting list for all requests
105 which didn't terminate. */
106 for (cnt = 0; cnt < ent; ++cnt)
107 if (list[cnt] != NULL && list[cnt]->__return == EAI_INPROGRESS
108 && requestlist[cnt] != NULL)
109 {
110 struct waitlist **listp = &requestlist[cnt]->waiting;
111
112 /* There is the chance that we cannot find our entry anymore.
113 This could happen if the request terminated and restarted
114 again. */
115 while (*listp != NULL && *listp != &waitlist[cnt])
116 listp = &(*listp)->next;
117
118 if (*listp != NULL)
119 *listp = (*listp)->next;
120 }
121
122 /* Now it's time to restore the cancelation state. */
123 __pthread_setcancelstate (oldstate, NULL);
124
125 #ifndef DONT_NEED_GAI_MISC_COND
126 /* Release the conditional variable. */
127 if (pthread_cond_destroy (&cond) != 0)
128 /* This must never happen. */
129 abort ();
130 #endif
131
132 if (result != 0)
133 {
134 /* An error occurred. Possibly it's EINTR. We have to translate
135 the timeout error report of `pthread_cond_timedwait' to the
136 form expected from `gai_suspend'. */
137 if (__glibc_likely (result == ETIMEDOUT))
138 result = EAI_AGAIN;
139 else if (result == EINTR)
140 result = EAI_INTR;
141 else
142 result = EAI_SYSTEM;
143 }
144 }
145
146 /* Release the mutex. */
147 __pthread_mutex_unlock (&__gai_requests_mutex);
148
149 return result;
150 }
151
152 #if __TIMESIZE == 64
153 # if PTHREAD_IN_LIBC
154 versioned_symbol (libc, ___gai_suspend_time64, gai_suspend, GLIBC_2_34);
155 # if OTHER_SHLIB_COMPAT (libanl, GLIBC_2_2_3, GLIBC_2_34)
156 compat_symbol (libanl, ___gai_suspend_time64, gai_suspend, GLIBC_2_2_3);
157 # endif
158 # else
159 weak_alias (___gai_suspend_time64, gai_suspend)
160 # endif /* PTHREAD_IN_LIBC */
161
162 #else /* __TIMESIZE != 64 */
163 # if PTHREAD_IN_LIBC
164 libc_hidden_ver (___gai_suspend_time64, __gai_suspend_time64)
165 versioned_symbol (libc, ___gai_suspend_time64, __gai_suspend_time64,
166 GLIBC_2_34);
167 # else /* !PTHREAD_IN_LIBC */
168 # if IS_IN (libanl)
169 hidden_ver (___gai_suspend_time64, __gai_suspend_time64)
170 # endif
171 #endif /* !PTHREAD_IN_LIBC */
172
173 int
174 ___gai_suspend (const struct gaicb *const list[], int ent,
175 const struct timespec *timeout)
176 {
177 struct __timespec64 ts64;
178
179 if (timeout != NULL)
180 ts64 = valid_timespec_to_timespec64 (*timeout);
181
182 return __gai_suspend_time64 (list, ent, timeout != NULL ? &ts64 : NULL);
183 }
184 #if PTHREAD_IN_LIBC
185 versioned_symbol (libc, ___gai_suspend, gai_suspend, GLIBC_2_34);
186 # if OTHER_SHLIB_COMPAT (libanl, GLIBC_2_2_3, GLIBC_2_34)
187 compat_symbol (libanl, ___gai_suspend, gai_suspend, GLIBC_2_2_3);
188 # endif
189 # else
190 weak_alias (___gai_suspend, gai_suspend)
191 # endif /* !PTHREAD_IN_LIBC */
192 #endif /* __TIMESIZE != 64 */