[2/2] y2038: linux: Provide __mq_timedreceive_time64 implementation
Commit Message
This patch provides new __mq_timedreceive_time64 explicit 64 bit function for
receiving messages with absolute timeout.
Moreover, a 32 bit version - __mq_timedreceive has been refactored to
internally use __mq_timedreceive_time64.
The __mq_timedreceive is now supposed to be used on systems still supporting 32
bit time (__TIMESIZE != 64) - hence the necessary conversion to 64 bit struct
__timespec64 from struct timespec.
The new mq_timerdsend_time64 syscall available from Linux 5.1+ has been used,
when applicable.
As this wrapper function is also used internally in the glibc, to e.g. provide
mq_receive implementation, an explicit check for abs_timeout being NULL has been
added due to conversions between struct timespec and struct __timespec64.
Before this change the Linux kernel handled this NULL pointer.
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
Linux kernel, headers and minimal kernel version for glibc build test matrix:
- Linux v5.1 (with mq_timedreceive_time64) and glibc built with v5.1 as
minimal kernel version (--enable-kernel="5.1.0")
The __ASSUME_TIME64_SYSCALLS flag defined.
- Linux v5.1 and default minimal kernel version
The __ASSUME_TIME64_SYSCALLS not defined, but kernel supports
mq_timedreceive_time64 syscall.
- Linux v4.19 (no mq_timedreceive_time64 support) with default minimal kernel
version for contemporary glibc (3.2.0)
This kernel doesn't support mq_timedreceive_time64 syscall, so the fallback to
mq_timedreceive is tested.
Above tests were performed with Y2038 redirection applied as well as without
(so the __TIMESIZE != 64 execution path is checked as well).
---
include/mqueue.h | 6 +++
sysdeps/unix/sysv/linux/mq_timedreceive.c | 51 +++++++++++++++++++++--
2 files changed, 53 insertions(+), 4 deletions(-)
@@ -12,11 +12,17 @@ hidden_proto (mq_setattr)
# endif
#if __TIMESIZE == 64
# define __mq_timedsend_time64 __mq_timedsend
+# define __mq_timedreceive_time64 __mq_timedreceive
#else
#include <include/time.h>
extern int __mq_timedsend_time64 (mqd_t mqdes, const char *msg_ptr,
size_t msg_len, unsigned int msg_prio,
const struct __timespec64 *abs_timeout);
librt_hidden_proto (__mq_timedsend_time64)
+extern 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);
+librt_hidden_proto (__mq_timedreceive_time64)
#endif
#endif
@@ -22,13 +22,56 @@
/* Receive the oldest from highest priority messages in message queue
MQDES, stop waiting if ABS_TIMEOUT expires. */
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)
+__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)
{
+#ifdef __ASSUME_TIME64_SYSCALLS
+# ifndef __NR_mq_timedreceive_time64
+# define __NR_mq_timedreceive_time64 __NR_mq_timedreceive
+# endif
+ return SYSCALL_CANCEL (mq_timedreceive_time64, mqdes, msg_ptr, msg_len,
+ msg_prio, abs_timeout);
+#else
+ int ret = SYSCALL_CANCEL (mq_timedreceive_time64, mqdes, msg_ptr, msg_len,
+ msg_prio, abs_timeout);
+ if (ret == 0 || errno != ENOSYS)
+ return ret;
+
+ struct timespec ts32;
+ if (abs_timeout)
+ {
+ if (! in_time_t_range (abs_timeout->tv_sec))
+ {
+ __set_errno (EOVERFLOW);
+ return -1;
+ }
+
+ ts32 = valid_timespec64_to_timespec (*abs_timeout);
+ }
+
return SYSCALL_CANCEL (mq_timedreceive, mqdes, msg_ptr, msg_len, msg_prio,
- abs_timeout);
+ abs_timeout ? &ts32 : NULL);
+#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)
+ ts64 = valid_timespec_to_timespec64 (*abs_timeout);
+
+ return __mq_timedreceive_time64 (mqdes, msg_ptr, msg_len, msg_prio,
+ abs_timeout ? &ts64 : NULL);
}
+#endif
+
hidden_def (__mq_timedreceive)
weak_alias (__mq_timedreceive, mq_timedreceive)
hidden_weak (mq_timedreceive)