[v2,1/2] y2038: linux: Provide __timerfd_gettime64 implementation
Commit Message
This patch replaces auto generated wrapper (as described in
sysdeps/unix/sysv/linux/syscalls.list) for timerfd_gettime with one which
adds extra support for reading 64 bit time values on machines with
__TIMESIZE != 64.
There is no functional change for architectures already supporting 64 bit
time ABI.
This patch is conceptually identical to timer_gettime conversion already
done in sysdeps/unix/sysv/linux/timer_gettime.c.
Please refer to corresponding commit message for detailed description of
introduced functions and the testing procedure.
---
Changes for v2:
- Remove "Contributed by" from the file header
- Remove early check for (fd < 0) in __timerfd_gettime64 as the fd
correctness check is already done in Linux kernel
- Add single descriptive comment line to provide concise explanation
of the code
---
include/time.h | 3 ++
sysdeps/unix/sysv/linux/Makefile | 3 +-
sysdeps/unix/sysv/linux/syscalls.list | 1 -
sysdeps/unix/sysv/linux/timerfd_gettime.c | 66 +++++++++++++++++++++++
4 files changed, 71 insertions(+), 2 deletions(-)
create mode 100644 sysdeps/unix/sysv/linux/timerfd_gettime.c
Comments
On Dez 11 2019, Lukasz Majewski wrote:
> diff --git a/sysdeps/unix/sysv/linux/timerfd_gettime.c b/sysdeps/unix/sysv/linux/timerfd_gettime.c
> new file mode 100644
> index 0000000000..18e1fd2991
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/timerfd_gettime.c
> @@ -0,0 +1,66 @@
> +/* timerfd_gettime -- get the timer setting referred to by file descriptor.
> + Copyright (C) 2019 Free Software Foundation, Inc.
> + This file is part of the GNU C Library.
> +
> + The GNU C Library is free software; you can redistribute it and/or
> + modify it under the terms of the GNU Lesser General Public License as
> + published by the Free Software Foundation; either version 2.1 of the
> + License, or (at your option) any later version.
> +
> + The GNU C Library is distributed in the hope that it will be useful,
> + but WITHOUT ANY WARRANTY; without even the implied warranty of
> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + Lesser General Public License for more details.
> +
> + You should have received a copy of the GNU Lesser General Public
> + License along with the GNU C Library; see the file COPYING.LIB. If
> + not, see <https://www.gnu.org/licenses/>. */
> +
> +#include <errno.h>
> +#include <stdlib.h>
> +#include <time.h>
> +#include <sysdep.h>
> +#include <kernel-features.h>
> +
> +int
> +__timerfd_gettime64 (int fd, struct __itimerspec64 *value)
> +{
> +#ifdef __ASSUME_TIME64_SYSCALLS
> +# ifndef __NR_timerfd_gettime64
> +# define __NR_timerfd_gettime64 __NR_timerfd_gettime
> +# endif
> + return INLINE_SYSCALL_CALL (timerfd_gettime64, fd, value);
> +#else
> +# ifdef __NR_timerfd_gettime64
> + int ret = INLINE_SYSCALL_CALL (timerfd_gettime64, fd, value);
> + if (ret == 0 || errno != ENOSYS)
> + return ret;
> +# endif
> + struct itimerspec its32;
> + int retval = INLINE_SYSCALL_CALL (timerfd_gettime, fd, &its32);
> + if (retval == 0)
> + {
> + value->it_interval = valid_timespec_to_timespec64 (its32.it_interval);
> + value->it_value = valid_timespec_to_timespec64 (its32.it_value);
> + }
> +
> + return retval;
> +#endif
> +}
You need a libc_hidden_def matching the libc_hidden_proto in
include/time.h.
Andreas.
Hi Andreas,
> On Dez 11 2019, Lukasz Majewski wrote:
>
> > diff --git a/sysdeps/unix/sysv/linux/timerfd_gettime.c
> > b/sysdeps/unix/sysv/linux/timerfd_gettime.c new file mode 100644
> > index 0000000000..18e1fd2991
> > --- /dev/null
> > +++ b/sysdeps/unix/sysv/linux/timerfd_gettime.c
> > @@ -0,0 +1,66 @@
> > +/* timerfd_gettime -- get the timer setting referred to by file
> > descriptor.
> > + Copyright (C) 2019 Free Software Foundation, Inc.
> > + This file is part of the GNU C Library.
> > +
> > + The GNU C Library is free software; you can redistribute it
> > and/or
> > + modify it under the terms of the GNU Lesser General Public
> > License as
> > + published by the Free Software Foundation; either version 2.1
> > of the
> > + License, or (at your option) any later version.
> > +
> > + The GNU C Library is distributed in the hope that it will be
> > useful,
> > + but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> > GNU
> > + Lesser General Public License for more details.
> > +
> > + You should have received a copy of the GNU Lesser General Public
> > + License along with the GNU C Library; see the file COPYING.LIB.
> > If
> > + not, see <https://www.gnu.org/licenses/>. */
> > +
> > +#include <errno.h>
> > +#include <stdlib.h>
> > +#include <time.h>
> > +#include <sysdep.h>
> > +#include <kernel-features.h>
> > +
> > +int
> > +__timerfd_gettime64 (int fd, struct __itimerspec64 *value)
> > +{
> > +#ifdef __ASSUME_TIME64_SYSCALLS
> > +# ifndef __NR_timerfd_gettime64
> > +# define __NR_timerfd_gettime64 __NR_timerfd_gettime
> > +# endif
> > + return INLINE_SYSCALL_CALL (timerfd_gettime64, fd, value);
> > +#else
> > +# ifdef __NR_timerfd_gettime64
> > + int ret = INLINE_SYSCALL_CALL (timerfd_gettime64, fd, value);
> > + if (ret == 0 || errno != ENOSYS)
> > + return ret;
> > +# endif
> > + struct itimerspec its32;
> > + int retval = INLINE_SYSCALL_CALL (timerfd_gettime, fd, &its32);
> > + if (retval == 0)
> > + {
> > + value->it_interval = valid_timespec_to_timespec64
> > (its32.it_interval);
> > + value->it_value = valid_timespec_to_timespec64
> > (its32.it_value);
> > + }
> > +
> > + return retval;
> > +#endif
> > +}
Thank you for your comment.
>
> You need a libc_hidden_def matching the libc_hidden_proto in
> include/time.h.
I'm a bit confused with this function. Before this patch, it was auto
generated from sysdeps/unix/sysv/linux/syscalls.list description.
From what I've dug (by examining the sysdeps/unix/make-syscalls.sh) it
was a "strong" symbol without the hidden definition.
Considering the above - there shall NOT be
+libc_hidden_proto (__timerfd_gettime64); in the first place.
Or do I miss something?
>
> Andreas.
>
Best regards,
Lukasz Majewski
--
DENX Software Engineering GmbH, Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma@denx.de
On Dez 11 2019, Lukasz Majewski wrote:
> From what I've dug (by examining the sysdeps/unix/make-syscalls.sh) it
> was a "strong" symbol without the hidden definition.
> Considering the above - there shall NOT be
>
> +libc_hidden_proto (__timerfd_gettime64); in the first place.
>
> Or do I miss something?
If the function is global and called within the same shlib, it needs to
have a hidden alias.
Andreas.
@@ -181,9 +181,12 @@ libc_hidden_proto (__futimens64);
#if __TIMESIZE == 64
# define __timer_gettime64 __timer_gettime
+# define __timerfd_gettime64 __timerfd_gettime
#else
extern int __timer_gettime64 (timer_t timerid, struct __itimerspec64 *value);
+extern int __timerfd_gettime64 (int fd, struct __itimerspec64 *value);
libc_hidden_proto (__timer_gettime64);
+libc_hidden_proto (__timerfd_gettime64);
#endif
#if __TIMESIZE == 64
@@ -18,7 +18,8 @@ sysdep_routines += adjtimex clone umount umount2 readahead \
setfsuid setfsgid epoll_pwait signalfd \
eventfd eventfd_read eventfd_write prlimit \
personality epoll_wait tee vmsplice splice \
- open_by_handle_at mlock2 pkey_mprotect pkey_set pkey_get
+ open_by_handle_at mlock2 pkey_mprotect pkey_set pkey_get \
+ timerfd_gettime
CFLAGS-gethostid.c = -fexceptions
CFLAGS-tee.c = -fexceptions -fasynchronous-unwind-tables
@@ -95,7 +95,6 @@ mq_setattr - mq_getsetattr i:ipp mq_setattr
timerfd_create EXTRA timerfd_create i:ii timerfd_create
timerfd_settime EXTRA timerfd_settime i:iipp timerfd_settime
-timerfd_gettime EXTRA timerfd_gettime i:ip timerfd_gettime
fanotify_init EXTRA fanotify_init i:ii fanotify_init
new file mode 100644
@@ -0,0 +1,66 @@
+/* timerfd_gettime -- get the timer setting referred to by file descriptor.
+ Copyright (C) 2019 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public License as
+ published by the Free Software Foundation; either version 2.1 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If
+ not, see <https://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <stdlib.h>
+#include <time.h>
+#include <sysdep.h>
+#include <kernel-features.h>
+
+int
+__timerfd_gettime64 (int fd, struct __itimerspec64 *value)
+{
+#ifdef __ASSUME_TIME64_SYSCALLS
+# ifndef __NR_timerfd_gettime64
+# define __NR_timerfd_gettime64 __NR_timerfd_gettime
+# endif
+ return INLINE_SYSCALL_CALL (timerfd_gettime64, fd, value);
+#else
+# ifdef __NR_timerfd_gettime64
+ int ret = INLINE_SYSCALL_CALL (timerfd_gettime64, fd, value);
+ if (ret == 0 || errno != ENOSYS)
+ return ret;
+# endif
+ struct itimerspec its32;
+ int retval = INLINE_SYSCALL_CALL (timerfd_gettime, fd, &its32);
+ if (retval == 0)
+ {
+ value->it_interval = valid_timespec_to_timespec64 (its32.it_interval);
+ value->it_value = valid_timespec_to_timespec64 (its32.it_value);
+ }
+
+ return retval;
+#endif
+}
+
+#if __TIMESIZE != 64
+int
+__timerfd_gettime (int fd, struct itimerspec *value)
+{
+ struct __itimerspec64 its64;
+ int retval = __timerfd_gettime64 (fd, &its64);
+ if (retval == 0)
+ {
+ value->it_interval = valid_timespec64_to_timespec (its64.it_interval);
+ value->it_value = valid_timespec64_to_timespec (its64.it_value);
+ }
+
+ return retval;
+}
+#endif
+strong_alias (__timerfd_gettime, timerfd_gettime)