1 /* time -- Get number of seconds since Epoch.  Linux version.
2    Copyright (C) 2020-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library 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 GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 /* Optimize the function call by setting the PLT directly to vDSO symbol.  */
20 #ifdef USE_IFUNC_TIME
21 # include <time.h>
22 # include <sysdep.h>
23 # include <sysdep-vdso.h>
24 
25 #ifdef SHARED
26 # include <dl-vdso.h>
27 # include <libc-vdso.h>
28 
29 static time_t
time_syscall(time_t * t)30 time_syscall (time_t *t)
31 {
32   return INLINE_SYSCALL_CALL (time, t);
33 }
34 
35 # undef INIT_ARCH
36 # define INIT_ARCH() \
37   void *vdso_time = dl_vdso_vsym (HAVE_TIME_VSYSCALL);
38 libc_ifunc (time,
39 	    vdso_time ? VDSO_IFUNC_RET (vdso_time)
40 		      : (void *) time_syscall);
41 
42 # else
43 time_t
time(time_t * t)44 time (time_t *t)
45 {
46   return INLINE_VSYSCALL (time, 1, t);
47 }
48 # endif /* !SHARED */
49 #else /* USE_IFUNC_TIME  */
50 # include <time.h>
51 # include <time-clockid.h>
52 # include <errno.h>
53 
54 /* Return the time now, and store it in *TIMER if not NULL.  */
55 
56 __time64_t
__time64(__time64_t * timer)57 __time64 (__time64_t *timer)
58 {
59   struct __timespec64 ts;
60   __clock_gettime64 (TIME_CLOCK_GETTIME_CLOCKID, &ts);
61 
62   if (timer != NULL)
63     *timer = ts.tv_sec;
64   return ts.tv_sec;
65 }
66 
67 # if __TIMESIZE != 64
libc_hidden_def(__time64)68 libc_hidden_def (__time64)
69 
70 time_t
71 __time (time_t *timer)
72 {
73   __time64_t t = __time64 (NULL);
74 
75   if (! in_time_t_range (t))
76     {
77       __set_errno (EOVERFLOW);
78       return -1;
79     }
80 
81   if (timer != NULL)
82     *timer = t;
83   return t;
84 }
85 # endif
86 weak_alias (__time, time)
87 #endif
88