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glibc/sysdeps/unix/sysv/linux/alpha/osf_settimeofday.c

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Linux/Alpha: don't use timeval32 system calls. Linux/Alpha has two versions of several system call wrappers that take or return data of type "struct timeval" (possibly nested inside a larger structure). The GLIBC_2.0 version is a compat symbol that calls __NR_osf_foo or __NR_old_foo and uses a struct timeval with a 32-bit tv_sec field. The GLIBC_2.1 version is used for current code, calls __NR_foo, and uses a struct timeval with a 64-bit tv_sec field. This patch changes all of the compat symbols of this type to be wrappers around their GLIBC_2.1 counterparts; the compatibility system calls will no longer be used. It serves as a proposal for part of how we do the transition to 64-bit time_t on systems that currently use 32-bit time_t: * The patched glibc will NOT use system calls that involve 32-bit time_t to implement its compatibility symbols. This will make both our lives and the kernel maintainers' lives easier. The primary argument I've seen against it is that the kernel could warn about uses of the old system calls, helping people find old binaries that need to be recompiled. I think there are several other ways we could accomplish this, e.g. scripts to scan the filesystem for binaries with references to the old symbol versions, or issuing diagnostics ourselves. * The compat symbols do NOT report failure after the Y2038 deadline. An earlier revision of this patch had them return -1 and set errno to EOVERFLOW, but Adhemerval pointed out that many of them have already performed side effects at the point where we discover the overflow, so that would break more than it fixes. Also, we don't want people to be _checking_ for EOVERFLOW from these functions; we want them to recompile with 64-bit time_t. So it's not actually useful for them to report failure to the calling code. * What they do do, when they encounter overflow, is saturate the overflowed "struct timeval"(s): tv_sec is set to INT32_MAX and tv_nsec is set to 999999. That means time stops advancing for programs with 32-bit time_t when they reach the deadline. That's obviously going to break stuff, but I think wrapping around is probably going to break _more_ stuff. I'd be interested to hear arguments against, if anyone has one. The new header file tv32-compat.h is currently Alpha-specific but I mean for it to be reused to aid in writing wrappers for all affected architectures. I only put it in sysdeps/unix/sysv/linux/alpha for now because I haven't checked whether the various "foo32" structures it defines agree with the ABI for ports other than Linux/Alpha. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-08-19 18:18:08 +00:00
/* settimeofday -- Set the current time of day. Linux/Alpha/tv32 version.
Update copyright dates with scripts/update-copyrights
2023-01-06 21:08:04 +00:00
Copyright (C) 2019-2023 Free Software Foundation, Inc.
Linux/Alpha: don't use timeval32 system calls. Linux/Alpha has two versions of several system call wrappers that take or return data of type "struct timeval" (possibly nested inside a larger structure). The GLIBC_2.0 version is a compat symbol that calls __NR_osf_foo or __NR_old_foo and uses a struct timeval with a 32-bit tv_sec field. The GLIBC_2.1 version is used for current code, calls __NR_foo, and uses a struct timeval with a 64-bit tv_sec field. This patch changes all of the compat symbols of this type to be wrappers around their GLIBC_2.1 counterparts; the compatibility system calls will no longer be used. It serves as a proposal for part of how we do the transition to 64-bit time_t on systems that currently use 32-bit time_t: * The patched glibc will NOT use system calls that involve 32-bit time_t to implement its compatibility symbols. This will make both our lives and the kernel maintainers' lives easier. The primary argument I've seen against it is that the kernel could warn about uses of the old system calls, helping people find old binaries that need to be recompiled. I think there are several other ways we could accomplish this, e.g. scripts to scan the filesystem for binaries with references to the old symbol versions, or issuing diagnostics ourselves. * The compat symbols do NOT report failure after the Y2038 deadline. An earlier revision of this patch had them return -1 and set errno to EOVERFLOW, but Adhemerval pointed out that many of them have already performed side effects at the point where we discover the overflow, so that would break more than it fixes. Also, we don't want people to be _checking_ for EOVERFLOW from these functions; we want them to recompile with 64-bit time_t. So it's not actually useful for them to report failure to the calling code. * What they do do, when they encounter overflow, is saturate the overflowed "struct timeval"(s): tv_sec is set to INT32_MAX and tv_nsec is set to 999999. That means time stops advancing for programs with 32-bit time_t when they reach the deadline. That's obviously going to break stuff, but I think wrapping around is probably going to break _more_ stuff. I'd be interested to hear arguments against, if anyone has one. The new header file tv32-compat.h is currently Alpha-specific but I mean for it to be reused to aid in writing wrappers for all affected architectures. I only put it in sysdeps/unix/sysv/linux/alpha for now because I haven't checked whether the various "foo32" structures it defines agree with the ABI for ports other than Linux/Alpha. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-08-19 18:18:08 +00:00
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 <shlib-compat.h>
#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
sysv/alpha: Use generic __timeval32 and helpers Now there is a generic __timeval32 and helpers we can use them for Alpha instead of the Alpha specific ones. Reviewed-by: Lukasz Majewski <lukma@denx.de> Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2020-02-11 21:16:14 +00:00
#include <time.h>
Linux/Alpha: don't use timeval32 system calls. Linux/Alpha has two versions of several system call wrappers that take or return data of type "struct timeval" (possibly nested inside a larger structure). The GLIBC_2.0 version is a compat symbol that calls __NR_osf_foo or __NR_old_foo and uses a struct timeval with a 32-bit tv_sec field. The GLIBC_2.1 version is used for current code, calls __NR_foo, and uses a struct timeval with a 64-bit tv_sec field. This patch changes all of the compat symbols of this type to be wrappers around their GLIBC_2.1 counterparts; the compatibility system calls will no longer be used. It serves as a proposal for part of how we do the transition to 64-bit time_t on systems that currently use 32-bit time_t: * The patched glibc will NOT use system calls that involve 32-bit time_t to implement its compatibility symbols. This will make both our lives and the kernel maintainers' lives easier. The primary argument I've seen against it is that the kernel could warn about uses of the old system calls, helping people find old binaries that need to be recompiled. I think there are several other ways we could accomplish this, e.g. scripts to scan the filesystem for binaries with references to the old symbol versions, or issuing diagnostics ourselves. * The compat symbols do NOT report failure after the Y2038 deadline. An earlier revision of this patch had them return -1 and set errno to EOVERFLOW, but Adhemerval pointed out that many of them have already performed side effects at the point where we discover the overflow, so that would break more than it fixes. Also, we don't want people to be _checking_ for EOVERFLOW from these functions; we want them to recompile with 64-bit time_t. So it's not actually useful for them to report failure to the calling code. * What they do do, when they encounter overflow, is saturate the overflowed "struct timeval"(s): tv_sec is set to INT32_MAX and tv_nsec is set to 999999. That means time stops advancing for programs with 32-bit time_t when they reach the deadline. That's obviously going to break stuff, but I think wrapping around is probably going to break _more_ stuff. I'd be interested to hear arguments against, if anyone has one. The new header file tv32-compat.h is currently Alpha-specific but I mean for it to be reused to aid in writing wrappers for all affected architectures. I only put it in sysdeps/unix/sysv/linux/alpha for now because I haven't checked whether the various "foo32" structures it defines agree with the ABI for ports other than Linux/Alpha. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-08-19 18:18:08 +00:00
#include <sys/time.h>
#include <time.h>
#include <errno.h>
/* Set the current time of day and timezone information.
This call is restricted to the super-user. */
int
attribute_compat_text_section
sysv/alpha: Use generic __timeval32 and helpers Now there is a generic __timeval32 and helpers we can use them for Alpha instead of the Alpha specific ones. Reviewed-by: Lukasz Majewski <lukma@denx.de> Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2020-02-11 21:16:14 +00:00
__settimeofday_tv32 (const struct __timeval32 *tv32,
Linux/Alpha: don't use timeval32 system calls. Linux/Alpha has two versions of several system call wrappers that take or return data of type "struct timeval" (possibly nested inside a larger structure). The GLIBC_2.0 version is a compat symbol that calls __NR_osf_foo or __NR_old_foo and uses a struct timeval with a 32-bit tv_sec field. The GLIBC_2.1 version is used for current code, calls __NR_foo, and uses a struct timeval with a 64-bit tv_sec field. This patch changes all of the compat symbols of this type to be wrappers around their GLIBC_2.1 counterparts; the compatibility system calls will no longer be used. It serves as a proposal for part of how we do the transition to 64-bit time_t on systems that currently use 32-bit time_t: * The patched glibc will NOT use system calls that involve 32-bit time_t to implement its compatibility symbols. This will make both our lives and the kernel maintainers' lives easier. The primary argument I've seen against it is that the kernel could warn about uses of the old system calls, helping people find old binaries that need to be recompiled. I think there are several other ways we could accomplish this, e.g. scripts to scan the filesystem for binaries with references to the old symbol versions, or issuing diagnostics ourselves. * The compat symbols do NOT report failure after the Y2038 deadline. An earlier revision of this patch had them return -1 and set errno to EOVERFLOW, but Adhemerval pointed out that many of them have already performed side effects at the point where we discover the overflow, so that would break more than it fixes. Also, we don't want people to be _checking_ for EOVERFLOW from these functions; we want them to recompile with 64-bit time_t. So it's not actually useful for them to report failure to the calling code. * What they do do, when they encounter overflow, is saturate the overflowed "struct timeval"(s): tv_sec is set to INT32_MAX and tv_nsec is set to 999999. That means time stops advancing for programs with 32-bit time_t when they reach the deadline. That's obviously going to break stuff, but I think wrapping around is probably going to break _more_ stuff. I'd be interested to hear arguments against, if anyone has one. The new header file tv32-compat.h is currently Alpha-specific but I mean for it to be reused to aid in writing wrappers for all affected architectures. I only put it in sysdeps/unix/sysv/linux/alpha for now because I haven't checked whether the various "foo32" structures it defines agree with the ABI for ports other than Linux/Alpha. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-08-19 18:18:08 +00:00
const struct timezone *tz)
{
Use clock_settime to implement settimeofday. Unconditionally, on all ports, use clock_settime to implement settimeofday. Remove sysdeps/unix/clock_settime.c, which implemented clock_settime by calling settimeofday; new OS ports must henceforth provide a real implementation of clock_settime. Hurd had a real implementation of settimeofday but not of clock_settime; this patch converts it into an implementation of clock_settime. It only supports CLOCK_REALTIME and microsecond resolution; Hurd/Mach does not appear to have any support for finer-resolution clocks. The vestigial "set time zone" feature of settimeofday complicates the generic settimeofday implementation a little. The only remaining uses of this feature that aren't just bugs, are using it to inform the Linux kernel of the offset between the hardware clock and UTC, on systems where the hardware clock doesn't run in UTC (usually because of dual-booting with Windows). There currently isn't any other way to do this. However, the callers that do this call settimeofday with _only_ the timezone argument non-NULL. Therefore, glibc's new behavior is: callers of settimeofday must supply one and only one of the two arguments. If both arguments are non-NULL, or both arguments are NULL, the call fails and sets errno to EINVAL. When only the timeval argument is supplied, settimeofday calls __clock_settime(CLOCK_REALTIME), same as stime. When only the timezone argument is supplied, settimeofday calls a new internal function called __settimezone. On Linux, only, this function will pass the timezone structure to the settimeofday system call. On all other operating systems, and on Linux architectures that don't define __NR_settimeofday, __settimezone is a stub that always sets errno to ENOSYS and returns -1. The settimeoday syscall is enabled on Linux by the flag COMPAT_32BIT_TIME, which is an option to either 32-bits ABIs or COMPAT builds (defined usually by 64-bit kernels that want to support 32-bit ABIs, such as x86). The idea to future 64-bit time_t only ABIs is to not provide settimeofday syscall. The same semantics are implemented for Linux/Alpha's GLIBC_2.0 compat symbol for settimeofday. There are no longer any internal callers of __settimeofday, so the internal prototype is removed. Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu, powerpc64-linux-gnu, powerpc-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> Reviewed-by: Lukasz Majewski <lukma@denx.de>
2019-08-28 12:25:49 +00:00
if (__glibc_unlikely (tz != 0))
{
if (tv32 != 0)
{
__set_errno (EINVAL);
return -1;
}
return __settimezone (tz);
}
sysv/alpha: Use generic __timeval32 and helpers Now there is a generic __timeval32 and helpers we can use them for Alpha instead of the Alpha specific ones. Reviewed-by: Lukasz Majewski <lukma@denx.de> Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2020-02-11 21:16:14 +00:00
struct timespec ts = valid_timeval32_to_timespec (*tv32);
Use clock_settime to implement settimeofday. Unconditionally, on all ports, use clock_settime to implement settimeofday. Remove sysdeps/unix/clock_settime.c, which implemented clock_settime by calling settimeofday; new OS ports must henceforth provide a real implementation of clock_settime. Hurd had a real implementation of settimeofday but not of clock_settime; this patch converts it into an implementation of clock_settime. It only supports CLOCK_REALTIME and microsecond resolution; Hurd/Mach does not appear to have any support for finer-resolution clocks. The vestigial "set time zone" feature of settimeofday complicates the generic settimeofday implementation a little. The only remaining uses of this feature that aren't just bugs, are using it to inform the Linux kernel of the offset between the hardware clock and UTC, on systems where the hardware clock doesn't run in UTC (usually because of dual-booting with Windows). There currently isn't any other way to do this. However, the callers that do this call settimeofday with _only_ the timezone argument non-NULL. Therefore, glibc's new behavior is: callers of settimeofday must supply one and only one of the two arguments. If both arguments are non-NULL, or both arguments are NULL, the call fails and sets errno to EINVAL. When only the timeval argument is supplied, settimeofday calls __clock_settime(CLOCK_REALTIME), same as stime. When only the timezone argument is supplied, settimeofday calls a new internal function called __settimezone. On Linux, only, this function will pass the timezone structure to the settimeofday system call. On all other operating systems, and on Linux architectures that don't define __NR_settimeofday, __settimezone is a stub that always sets errno to ENOSYS and returns -1. The settimeoday syscall is enabled on Linux by the flag COMPAT_32BIT_TIME, which is an option to either 32-bits ABIs or COMPAT builds (defined usually by 64-bit kernels that want to support 32-bit ABIs, such as x86). The idea to future 64-bit time_t only ABIs is to not provide settimeofday syscall. The same semantics are implemented for Linux/Alpha's GLIBC_2.0 compat symbol for settimeofday. There are no longer any internal callers of __settimeofday, so the internal prototype is removed. Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu, powerpc64-linux-gnu, powerpc-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> Reviewed-by: Lukasz Majewski <lukma@denx.de>
2019-08-28 12:25:49 +00:00
return __clock_settime (CLOCK_REALTIME, &ts);
Linux/Alpha: don't use timeval32 system calls. Linux/Alpha has two versions of several system call wrappers that take or return data of type "struct timeval" (possibly nested inside a larger structure). The GLIBC_2.0 version is a compat symbol that calls __NR_osf_foo or __NR_old_foo and uses a struct timeval with a 32-bit tv_sec field. The GLIBC_2.1 version is used for current code, calls __NR_foo, and uses a struct timeval with a 64-bit tv_sec field. This patch changes all of the compat symbols of this type to be wrappers around their GLIBC_2.1 counterparts; the compatibility system calls will no longer be used. It serves as a proposal for part of how we do the transition to 64-bit time_t on systems that currently use 32-bit time_t: * The patched glibc will NOT use system calls that involve 32-bit time_t to implement its compatibility symbols. This will make both our lives and the kernel maintainers' lives easier. The primary argument I've seen against it is that the kernel could warn about uses of the old system calls, helping people find old binaries that need to be recompiled. I think there are several other ways we could accomplish this, e.g. scripts to scan the filesystem for binaries with references to the old symbol versions, or issuing diagnostics ourselves. * The compat symbols do NOT report failure after the Y2038 deadline. An earlier revision of this patch had them return -1 and set errno to EOVERFLOW, but Adhemerval pointed out that many of them have already performed side effects at the point where we discover the overflow, so that would break more than it fixes. Also, we don't want people to be _checking_ for EOVERFLOW from these functions; we want them to recompile with 64-bit time_t. So it's not actually useful for them to report failure to the calling code. * What they do do, when they encounter overflow, is saturate the overflowed "struct timeval"(s): tv_sec is set to INT32_MAX and tv_nsec is set to 999999. That means time stops advancing for programs with 32-bit time_t when they reach the deadline. That's obviously going to break stuff, but I think wrapping around is probably going to break _more_ stuff. I'd be interested to hear arguments against, if anyone has one. The new header file tv32-compat.h is currently Alpha-specific but I mean for it to be reused to aid in writing wrappers for all affected architectures. I only put it in sysdeps/unix/sysv/linux/alpha for now because I haven't checked whether the various "foo32" structures it defines agree with the ABI for ports other than Linux/Alpha. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2019-08-19 18:18:08 +00:00
}
compat_symbol (libc, __settimeofday_tv32, settimeofday, GLIBC_2_0);
#endif
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