y2038: linux: Provide __timerfd_gettime64 implementation

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.

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>

---
Changes for v4:
- Update date from 2019 to 2020

Changes for v3:
- Add missing libc_hidden_def()

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

1 files changed, 3 insertions, 0 deletions

diff --git a/include/time.h b/include/time.h
index e5e8246eac..eb5082b4d7 100644
--- a/include/time.h
+++ b/include/time.h
@@ -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