| Message ID | 20190820132152.24100-5-zackw@panix.com |
|---|---|
| State | New |
| Headers | show |
| Series | Y2038 preparation: use clock_[gs]ettime to implement the other time-getting and -setting functions | expand |
On 20/08/2019 10:21, Zack Weinberg wrote: > Unconditionally, on all ports, use clock_settime to implement stime, > not settimeofday or a direct syscall. > > Note that the former stub implementation of stime would return -1 with > errno set to EINVAL if passed a null pointer. With this change, it > instead unconditionally dereferences the pointer, so any hypothetical > callers that passed NULL will now segfault. I don’t think this will break > any non-contrived programs. I agree that using a null point does not make sense, so I would also recommend to use __nonnull ((1)) on function prototype as well. > > * time/stime.c (stime): No longer a stub implementation. > Call __clock_settime. > > * sysdeps/unix/stime.c: Delete file. > * sysdeps/unix/sysv/linux/syscalls.list: Remove entry for stime. > > * include/time.h: Add libc_hidden_proto for __clock_settime. > * rt/clock_settime.c, sysdeps/unix/sysv/linux/clock_settime.c: > Add libc_hidden_def for __clock_settime. LGTM. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> > --- > include/time.h | 1 + > rt/clock_settime.c | 1 + > sysdeps/unix/stime.c | 39 ------------------------- > sysdeps/unix/sysv/linux/clock_settime.c | 1 + > sysdeps/unix/sysv/linux/syscalls.list | 1 - > time/stime.c | 15 +++------- > 6 files changed, 7 insertions(+), 51 deletions(-) > delete mode 100644 sysdeps/unix/stime.c > > diff --git a/include/time.h b/include/time.h > index ac3163c2a5..c0421c7a28 100644 > --- a/include/time.h > +++ b/include/time.h > @@ -22,6 +22,7 @@ extern __typeof (clock_getres) __clock_getres; > extern __typeof (clock_gettime) __clock_gettime; > libc_hidden_proto (__clock_gettime) > extern __typeof (clock_settime) __clock_settime; > +libc_hidden_proto (__clock_settime) > extern __typeof (clock_nanosleep) __clock_nanosleep; > extern __typeof (clock_getcpuclockid) __clock_getcpuclockid; > Ok. > diff --git a/rt/clock_settime.c b/rt/clock_settime.c > index 891925ab2c..9c4f4fbc10 100644 > --- a/rt/clock_settime.c > +++ b/rt/clock_settime.c > @@ -26,5 +26,6 @@ __clock_settime (clockid_t clock_id, const struct timespec *tp) > __set_errno (ENOSYS); > return -1; > } > +libc_hidden_def (__clock_settime) > weak_alias (__clock_settime, clock_settime) > stub_warning (clock_settime) Ok. > diff --git a/sysdeps/unix/stime.c b/sysdeps/unix/stime.c > deleted file mode 100644 > index b0809be400..0000000000 > --- a/sysdeps/unix/stime.c > +++ /dev/null > @@ -1,39 +0,0 @@ > -/* Copyright (C) 1992-2019 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; if not, see > - <http://www.gnu.org/licenses/>. */ > - > -#include <errno.h> > -#include <stddef.h> /* For NULL. */ > -#include <sys/time.h> > -#include <time.h> > - > -/* Set the system clock to *WHEN. */ > - > -int > -stime (const time_t *when) > -{ > - struct timeval tv; > - > - if (when == NULL) > - { > - __set_errno (EINVAL); > - return -1; > - } > - > - tv.tv_sec = *when; > - tv.tv_usec = 0; > - return __settimeofday (&tv, (struct timezone *) 0); > -} Ok. > diff --git a/sysdeps/unix/sysv/linux/clock_settime.c b/sysdeps/unix/sysv/linux/clock_settime.c > index d837e3019c..ef1512cc91 100644 > --- a/sysdeps/unix/sysv/linux/clock_settime.c > +++ b/sysdeps/unix/sysv/linux/clock_settime.c > @@ -34,4 +34,5 @@ __clock_settime (clockid_t clock_id, const struct timespec *tp) > > return INLINE_SYSCALL_CALL (clock_settime, clock_id, tp); > } > +libc_hidden_def (__clock_settime) > weak_alias (__clock_settime, clock_settime) Ok. > diff --git a/sysdeps/unix/sysv/linux/syscalls.list b/sysdeps/unix/sysv/linux/syscalls.list > index e374f97b5f..f6cb655e2c 100644 > --- a/sysdeps/unix/sysv/linux/syscalls.list > +++ b/sysdeps/unix/sysv/linux/syscalls.list > @@ -62,7 +62,6 @@ setfsgid EXTRA setfsgid i:i setfsgid > setfsuid EXTRA setfsuid i:i setfsuid > setpgid - setpgid i:ii __setpgid setpgid > sigaltstack - sigaltstack i:PP __sigaltstack sigaltstack > -stime - stime i:p stime > sysinfo EXTRA sysinfo i:p __sysinfo sysinfo > swapon - swapon i:si __swapon swapon > swapoff - swapoff i:s __swapoff swapoff Ok. > diff --git a/time/stime.c b/time/stime.c > index de58c49562..b4d692ca32 100644 > --- a/time/stime.c > +++ b/time/stime.c > @@ -15,23 +15,16 @@ > License along with the GNU C Library; if not, see > <http://www.gnu.org/licenses/>. */ > > -#include <errno.h> > #include <time.h> > -#include <stddef.h> > > /* Set the system clock to *WHEN. */ > > int > stime (const time_t *when) > { > - if (when == NULL) > - { > - __set_errno (EINVAL); > - return -1; > - } > + struct timespec ts; > + ts.tv_sec = *when; > + ts.tv_nsec = 0; > > - __set_errno (ENOSYS); > - return -1; > + return __clock_settime (CLOCK_REALTIME, &ts); > } > - > -stub_warning (stime) > Ok.
On 8/21/19 11:10 AM, Adhemerval Zanella wrote: > > > On 20/08/2019 10:21, Zack Weinberg wrote: >> Unconditionally, on all ports, use clock_settime to implement stime, >> not settimeofday or a direct syscall. >> >> Note that the former stub implementation of stime would return -1 with >> errno set to EINVAL if passed a null pointer. With this change, it >> instead unconditionally dereferences the pointer, so any hypothetical >> callers that passed NULL will now segfault. I don’t think this will break >> any non-contrived programs. > > I agree that using a null point does not make sense, so I would also recommend > to use __nonnull ((1)) on function prototype as well. Good point, but I'm not going to make this change because instead I'm going to add a patch to the series that demotes stime to a compatibility symbol, so its public prototype will be removed. zw
diff --git a/include/time.h b/include/time.h index ac3163c2a5..c0421c7a28 100644 --- a/include/time.h +++ b/include/time.h @@ -22,6 +22,7 @@ extern __typeof (clock_getres) __clock_getres; extern __typeof (clock_gettime) __clock_gettime; libc_hidden_proto (__clock_gettime) extern __typeof (clock_settime) __clock_settime; +libc_hidden_proto (__clock_settime) extern __typeof (clock_nanosleep) __clock_nanosleep; extern __typeof (clock_getcpuclockid) __clock_getcpuclockid; diff --git a/rt/clock_settime.c b/rt/clock_settime.c index 891925ab2c..9c4f4fbc10 100644 --- a/rt/clock_settime.c +++ b/rt/clock_settime.c @@ -26,5 +26,6 @@ __clock_settime (clockid_t clock_id, const struct timespec *tp) __set_errno (ENOSYS); return -1; } +libc_hidden_def (__clock_settime) weak_alias (__clock_settime, clock_settime) stub_warning (clock_settime) diff --git a/sysdeps/unix/stime.c b/sysdeps/unix/stime.c deleted file mode 100644 index b0809be400..0000000000 --- a/sysdeps/unix/stime.c +++ /dev/null @@ -1,39 +0,0 @@ -/* Copyright (C) 1992-2019 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; if not, see - <http://www.gnu.org/licenses/>. */ - -#include <errno.h> -#include <stddef.h> /* For NULL. */ -#include <sys/time.h> -#include <time.h> - -/* Set the system clock to *WHEN. */ - -int -stime (const time_t *when) -{ - struct timeval tv; - - if (when == NULL) - { - __set_errno (EINVAL); - return -1; - } - - tv.tv_sec = *when; - tv.tv_usec = 0; - return __settimeofday (&tv, (struct timezone *) 0); -} diff --git a/sysdeps/unix/sysv/linux/clock_settime.c b/sysdeps/unix/sysv/linux/clock_settime.c index d837e3019c..ef1512cc91 100644 --- a/sysdeps/unix/sysv/linux/clock_settime.c +++ b/sysdeps/unix/sysv/linux/clock_settime.c @@ -34,4 +34,5 @@ __clock_settime (clockid_t clock_id, const struct timespec *tp) return INLINE_SYSCALL_CALL (clock_settime, clock_id, tp); } +libc_hidden_def (__clock_settime) weak_alias (__clock_settime, clock_settime) diff --git a/sysdeps/unix/sysv/linux/syscalls.list b/sysdeps/unix/sysv/linux/syscalls.list index e374f97b5f..f6cb655e2c 100644 --- a/sysdeps/unix/sysv/linux/syscalls.list +++ b/sysdeps/unix/sysv/linux/syscalls.list @@ -62,7 +62,6 @@ setfsgid EXTRA setfsgid i:i setfsgid setfsuid EXTRA setfsuid i:i setfsuid setpgid - setpgid i:ii __setpgid setpgid sigaltstack - sigaltstack i:PP __sigaltstack sigaltstack -stime - stime i:p stime sysinfo EXTRA sysinfo i:p __sysinfo sysinfo swapon - swapon i:si __swapon swapon swapoff - swapoff i:s __swapoff swapoff diff --git a/time/stime.c b/time/stime.c index de58c49562..b4d692ca32 100644 --- a/time/stime.c +++ b/time/stime.c @@ -15,23 +15,16 @@ License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ -#include <errno.h> #include <time.h> -#include <stddef.h> /* Set the system clock to *WHEN. */ int stime (const time_t *when) { - if (when == NULL) - { - __set_errno (EINVAL); - return -1; - } + struct timespec ts; + ts.tv_sec = *when; + ts.tv_nsec = 0; - __set_errno (ENOSYS); - return -1; + return __clock_settime (CLOCK_REALTIME, &ts); } - -stub_warning (stime)