[PULL 17/18] linux-user: Add support for 'rt_sigtimedwait_time64()' and 'sched_rr_get_interval_time64()'

[Laurent Vivier <laurent@vivier.eu>]

From: Filip Bozuta <Filip.Bozuta@syrmia.com>

This patch implements functionality for following time64 syscalls:

*rt_sigtimedwait_time64()

    This is a year 2038 safe variant of syscall:

    int rt_sigtimedwait(const sigset_t *set, siginfo_t *info,
                        const struct timespec *timeout, size_t sigsetsize)
    --synchronously wait for queued signals--
    man page: https://man7.org/linux/man-pages/man2/rt_sigtimedwait.2.html

*sched_rr_get_interval_time64()

    This is a year 2038 safe variant of syscall:

    int sched_rr_get_interval(pid_t pid, struct timespec *tp)
    --get  the  SCHED_RR  interval  for the named process--
    man page: https://man7.org/linux/man-pages/man2/sched_rr_get_interval.2.html

Implementation notes:

    These syscalls were implemented in similar ways like
    'rt_sigtimedwait()' and 'sched_rr_get_interval()' except
    that functions 'target_to_host_timespec64()' and
    'host_to_target_timespec64()' were used to convert values
    of 'struct timespec' between host and target.

Signed-off-by: Filip Bozuta <Filip.Bozuta@syrmia.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20200824192116.65562-3-Filip.Bozuta@syrmia.com>
[lv: add missing defined(TARGET_NR_rt_sigtimedwait_time64)]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
---
 linux-user/syscall.c | 58 ++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 56 insertions(+), 2 deletions(-)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 82414c08d655..9d7376734ad4 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -764,7 +764,7 @@ safe_syscall6(ssize_t, recvfrom, int, fd, void *, buf, size_t, len,
 safe_syscall3(ssize_t, sendmsg, int, fd, const struct msghdr *, msg, int, flags)
 safe_syscall3(ssize_t, recvmsg, int, fd, struct msghdr *, msg, int, flags)
 safe_syscall2(int, flock, int, fd, int, operation)
-#ifdef TARGET_NR_rt_sigtimedwait
+#if defined(TARGET_NR_rt_sigtimedwait) || defined(TARGET_NR_rt_sigtimedwait_time64)
 safe_syscall4(int, rt_sigtimedwait, const sigset_t *, these, siginfo_t *, uinfo,
               const struct timespec *, uts, size_t, sigsetsize)
 #endif
@@ -1241,7 +1241,8 @@ static inline abi_long target_to_host_timespec(struct timespec *host_ts,
     defined(TARGET_NR_mq_timedsend_time64) || \
     defined(TARGET_NR_mq_timedreceive_time64) || \
     (defined(TARGET_NR_timerfd_settime64) && defined(CONFIG_TIMERFD)) || \
-    defined(TARGET_NR_clock_nanosleep_time64)
+    defined(TARGET_NR_clock_nanosleep_time64) || \
+    defined(TARGET_NR_rt_sigtimedwait_time64)
 static inline abi_long target_to_host_timespec64(struct timespec *host_ts,
                                                  abi_ulong target_addr)
 {
@@ -9042,6 +9043,48 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
             }
         }
         return ret;
+#endif
+#ifdef TARGET_NR_rt_sigtimedwait_time64
+    case TARGET_NR_rt_sigtimedwait_time64:
+        {
+            sigset_t set;
+            struct timespec uts, *puts;
+            siginfo_t uinfo;
+
+            if (arg4 != sizeof(target_sigset_t)) {
+                return -TARGET_EINVAL;
+            }
+
+            p = lock_user(VERIFY_READ, arg1, sizeof(target_sigset_t), 1);
+            if (!p) {
+                return -TARGET_EFAULT;
+            }
+            target_to_host_sigset(&set, p);
+            unlock_user(p, arg1, 0);
+            if (arg3) {
+                puts = &uts;
+                if (target_to_host_timespec64(puts, arg3)) {
+                    return -TARGET_EFAULT;
+                }
+            } else {
+                puts = NULL;
+            }
+            ret = get_errno(safe_rt_sigtimedwait(&set, &uinfo, puts,
+                                                 SIGSET_T_SIZE));
+            if (!is_error(ret)) {
+                if (arg2) {
+                    p = lock_user(VERIFY_WRITE, arg2,
+                                  sizeof(target_siginfo_t), 0);
+                    if (!p) {
+                        return -TARGET_EFAULT;
+                    }
+                    host_to_target_siginfo(p, &uinfo);
+                    unlock_user(p, arg2, sizeof(target_siginfo_t));
+                }
+                ret = host_to_target_signal(ret);
+            }
+        }
+        return ret;
 #endif
     case TARGET_NR_rt_sigqueueinfo:
         {
@@ -10566,6 +10609,17 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
         }
         return ret;
 #endif
+#ifdef TARGET_NR_sched_rr_get_interval_time64
+    case TARGET_NR_sched_rr_get_interval_time64:
+        {
+            struct timespec ts;
+            ret = get_errno(sched_rr_get_interval(arg1, &ts));
+            if (!is_error(ret)) {
+                ret = host_to_target_timespec64(arg2, &ts);
+            }
+        }
+        return ret;
+#endif
 #if defined(TARGET_NR_nanosleep)
     case TARGET_NR_nanosleep:
         {
-- 
2.26.2