1 /* gettimeofday - set time.  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 License as
7    published by the Free Software Foundation; either version 2.1 of the
8    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 #include <time.h>
20 #include <string.h>
21 
22 /* Optimize the function call by setting the PLT directly to vDSO symbol.  */
23 #ifdef USE_IFUNC_GETTIMEOFDAY
24 # include <sysdep.h>
25 # include <sysdep-vdso.h>
26 
27 # ifdef SHARED
28 # include <dl-vdso.h>
29 # include <libc-vdso.h>
30 
31 static int
__gettimeofday_syscall(struct timeval * restrict tv,void * restrict tz)32 __gettimeofday_syscall (struct timeval *restrict tv, void *restrict tz)
33 {
34   if (__glibc_unlikely (tz != 0))
35     memset (tz, 0, sizeof *tz);
36   return INLINE_SYSCALL_CALL (gettimeofday, tv, tz);
37 }
38 
39 # undef INIT_ARCH
40 # define INIT_ARCH() \
41   void *vdso_gettimeofday = dl_vdso_vsym (HAVE_GETTIMEOFDAY_VSYSCALL)
42 libc_ifunc (__gettimeofday,
43 	    vdso_gettimeofday ? VDSO_IFUNC_RET (vdso_gettimeofday)
44 			      : (void *) __gettimeofday_syscall)
45 
46 # else
47 int
48 __gettimeofday (struct timeval *restrict tv, void *restrict tz)
49 {
50   if (__glibc_unlikely (tz != 0))
51     memset (tz, 0, sizeof *tz);
52 
53   return INLINE_VSYSCALL (gettimeofday, 2, tv, tz);
54 }
55 # endif
56 weak_alias (__gettimeofday, gettimeofday)
57 #else /* USE_IFUNC_GETTIMEOFDAY  */
58 /* Conversion of gettimeofday function to support 64 bit time on archs
59    with __WORDSIZE == 32 and __TIMESIZE == 32/64  */
60 #include <errno.h>
61 
62 int
63 __gettimeofday64 (struct __timeval64 *restrict tv, void *restrict tz)
64 {
65   if (__glibc_unlikely (tz != 0))
66     memset (tz, 0, sizeof (struct timezone));
67 
68   struct __timespec64 ts64;
69   if (__clock_gettime64 (CLOCK_REALTIME, &ts64))
70 	  return -1;
71 
72   *tv = timespec64_to_timeval64 (ts64);
73   return 0;
74 }
75 
76 # if __TIMESIZE != 64
77 libc_hidden_def (__gettimeofday64)
78 
79 int
80 __gettimeofday (struct timeval *restrict tv, void *restrict tz)
81 {
82   struct __timeval64 tv64;
83   if (__gettimeofday64 (&tv64, tz))
84 	  return -1;
85 
86   if (! in_time_t_range (tv64.tv_sec))
87     {
88       __set_errno (EOVERFLOW);
89       return -1;
90     }
91 
92   *tv = valid_timeval64_to_timeval (tv64);
93   return 0;
94 }
95 # endif
96 weak_alias (__gettimeofday, gettimeofday)
97 #endif
98