glibc/sysdeps/unix/sysv/linux/mq_timedreceive.c
Adhemerval Zanella e9e912d334 linux: Only use 64-bit syscall if required for mq_timedreceive
For !__ASSUME_TIME64_SYSCALLS there is no need to issue a 64-bit syscall
if the provided timeout fits in a 32-bit one.  The 64-bit usage should
be rare since the timeout is a relative one.

Checked on i686-linux-gnu on a 4.15 kernel and on a 5.11 kernel
(with and without --enable-kernel=5.1) and on x86_64-linux-gnu.

Reviewed-by: Lukasz Majewski <lukma@denx.de>
2021-06-22 12:09:52 -03:00

81 lines
2.7 KiB
C

/* Receive a message from a message queue with a timeout. Linux version.
Copyright (C) 2017-2021 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
<https://www.gnu.org/licenses/>. */
#include <mqueue.h>
#include <sysdep-cancel.h>
/* Receive the oldest from highest priority messages in message queue
MQDES, stop waiting if ABS_TIMEOUT expires. */
ssize_t
__mq_timedreceive_time64 (mqd_t mqdes, char *__restrict msg_ptr, size_t msg_len,
unsigned int *__restrict msg_prio,
const struct __timespec64 *__restrict abs_timeout)
{
#ifndef __NR_mq_timedreceive_time64
# define __NR_mq_timedreceive_time64 __NR_mq_timedreceive
#endif
#ifdef __ASSUME_TIME64_SYSCALLS
return SYSCALL_CANCEL (mq_timedreceive_time64, mqdes, msg_ptr, msg_len,
msg_prio, abs_timeout);
#else
bool need_time64 = abs_timeout != NULL
&& !in_time_t_range (abs_timeout->tv_sec);
if (need_time64)
{
int r = SYSCALL_CANCEL (mq_timedreceive_time64, mqdes, msg_ptr, msg_len,
msg_prio, abs_timeout);
if (r == 0 || errno != ENOSYS)
return r;
__set_errno (EOVERFLOW);
return -1;
}
struct timespec ts32, *pts32 = NULL;
if (abs_timeout != NULL)
{
ts32 = valid_timespec64_to_timespec (*abs_timeout);
pts32 = &ts32;
}
return SYSCALL_CANCEL (mq_timedreceive, mqdes, msg_ptr, msg_len, msg_prio,
pts32);
#endif
}
#if __TIMESIZE != 64
librt_hidden_def (__mq_timedreceive_time64)
ssize_t
__mq_timedreceive (mqd_t mqdes, char *__restrict msg_ptr, size_t msg_len,
unsigned int *__restrict msg_prio,
const struct timespec *__restrict abs_timeout)
{
struct __timespec64 ts64;
if (abs_timeout != NULL)
ts64 = valid_timespec_to_timespec64 (*abs_timeout);
return __mq_timedreceive_time64 (mqdes, msg_ptr, msg_len, msg_prio,
abs_timeout != NULL ? &ts64 : NULL);
}
#endif
hidden_def (__mq_timedreceive)
weak_alias (__mq_timedreceive, mq_timedreceive)
hidden_weak (mq_timedreceive)