From: Lukasz Majewski <lukma@denx.de>
To: Joseph Myers <joseph@codesourcery.com>,
Paul Eggert <eggert@cs.ucla.edu>,
Adhemerval Zanella <adhemerval.zanella@linaro.org>
Cc: Alistair Francis <alistair23@gmail.com>,
Arnd Bergmann <arnd@arndb.de>,
Alistair Francis <alistair.francis@wdc.com>,
GNU C Library <libc-alpha@sourceware.org>,
Florian Weimer <fweimer@redhat.com>,
Carlos O'Donell <carlos@redhat.com>,
Stepan Golosunov <stepan@golosunov.pp.ru>,
Andreas Schwab <schwab@suse.de>, Zack Weinberg <zackw@panix.com>,
Lukasz Majewski <lukma@denx.de>
Subject: [PATCH] y2038: linux: Provide __time64 implementation
Date: Thu, 15 Oct 2020 14:34:29 +0200 [thread overview]
Message-ID: <20201015123429.5446-1-lukma@denx.de> (raw)
In the glibc the time function can use vDSO (on power and x86 the
USE_IFUNC_TIME is defined), time syscall or 'default' time() from
./time/time.c (as a fallback).
In this patch the last function (time) has been refactored and moved
to ./sysdeps/unix/sysv/linux/time.c to be Linux specific.
The new __time64 explicit 64 bit function for providing 64 bit value of
seconds after epoch (by internally calling __clock_gettime64) has been
introduced.
Moreover, a 32 bit version - __time has been refactored to internally
use __time64.
The __time is now supposed to be used on systems still supporting 32 bit
time (__TIMESIZE != 64) - hence the necessary check for time_t potential
overflow.
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Run-time tests:
- Run specific tests on ARM/x86 32bit systems (qemu):
https://github.com/lmajewski/meta-y2038 and run tests:
https://github.com/lmajewski/y2038-tests/commits/master
Above tests were performed with Y2038 redirection applied as well as without
to test proper usage of both __time64 and __time.
---
include/time.h | 7 ++++++
sysdeps/unix/sysv/linux/time.c | 39 +++++++++++++++++++++++++++++++++-
2 files changed, 45 insertions(+), 1 deletion(-)
diff --git a/include/time.h b/include/time.h
index edf6cdf829..caf2af5e74 100644
--- a/include/time.h
+++ b/include/time.h
@@ -317,6 +317,13 @@ extern int __timespec_get64 (struct __timespec64 *ts, int base);
libc_hidden_proto (__timespec_get64)
#endif
+#if __TIMESIZE == 64
+# define __time64 __time
+#else
+extern __time64_t __time64 (__time64_t *timer);
+libc_hidden_proto (__time64)
+#endif
+
/* Use in the clock_* functions. Size of the field representing the
actual clock ID. */
#define CLOCK_IDFIELD_SIZE 3
diff --git a/sysdeps/unix/sysv/linux/time.c b/sysdeps/unix/sysv/linux/time.c
index 9d8e573c0a..1a9a7c0413 100644
--- a/sysdeps/unix/sysv/linux/time.c
+++ b/sysdeps/unix/sysv/linux/time.c
@@ -47,5 +47,42 @@ time (time_t *t)
}
# endif /* !SHARED */
#else /* USE_IFUNC_TIME */
-# include <time/time.c>
+/* Conversion of time function to support 64 bit time on archs
+ with __WORDSIZE == 32 and __TIMESIZE == 32/64 */
+# include <time.h>
+# include <time-clockid.h>
+# include <errno.h>
+/* Return the time now, and store it in *TIMER if not NULL. */
+
+__time64_t
+__time64 (__time64_t *timer)
+{
+ struct __timespec64 ts;
+ __clock_gettime64 (TIME_CLOCK_GETTIME_CLOCKID, &ts);
+
+ if (timer)
+ *timer = ts.tv_sec;
+ return ts.tv_sec;
+}
+
+# if __TIMESIZE != 64
+libc_hidden_def (__time64)
+
+time_t
+__time (time_t *timer)
+{
+ __time64_t t = __time64 (NULL);
+
+ if (! in_time_t_range (t))
+ {
+ __set_errno (EOVERFLOW);
+ return -1;
+ }
+
+ if (timer)
+ *timer = t;
+ return t;
+}
+# endif
+weak_alias (__time, time)
#endif
--
2.20.1
next reply other threads:[~2020-10-15 12:35 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-15 12:34 Lukasz Majewski [this message]
2020-10-15 13:03 ` Adhemerval Zanella
2020-10-16 10:18 ` Lukasz Majewski
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