[PATCH v9 2/4] linux-user/syscall: Add support for clock_gettime64/clock_settime64

[Alistair Francis <alistair.francis@wdc.com>]

Add support for the clock_gettime64/clock_settime64 syscalls.

If your host is 64-bit or is 32-bit with the *_time64 syscall then the
timespec will correctly be a 64-bit time_t. Otherwise the host will
return a 32-bit time_t which will be rounded to 64-bits. This will be
incorrect after y2038.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
---
 linux-user/syscall.c | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 909bec94a5..60fd775d9c 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -1229,6 +1229,22 @@ static inline abi_long target_to_host_timespec(struct timespec *host_ts,
 }
 #endif
 
+#if defined(TARGET_NR_clock_settime64)
+static inline abi_long target_to_host_timespec64(struct timespec *host_ts,
+                                                 abi_ulong target_addr)
+{
+    struct target__kernel_timespec *target_ts;
+
+    if (!lock_user_struct(VERIFY_READ, target_ts, target_addr, 1)) {
+        return -TARGET_EFAULT;
+    }
+    __get_user(host_ts->tv_sec, &target_ts->tv_sec);
+    __get_user(host_ts->tv_nsec, &target_ts->tv_nsec);
+    unlock_user_struct(target_ts, target_addr, 0);
+    return 0;
+}
+#endif
+
 static inline abi_long host_to_target_timespec(abi_ulong target_addr,
                                                struct timespec *host_ts)
 {
@@ -11458,6 +11474,18 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
         return ret;
     }
 #endif
+#ifdef TARGET_NR_clock_settime64
+    case TARGET_NR_clock_settime64:
+    {
+        struct timespec ts;
+
+        ret = target_to_host_timespec64(&ts, arg2);
+        if (!is_error(ret)) {
+            ret = get_errno(clock_settime(arg1, &ts));
+        }
+        return ret;
+    }
+#endif
 #ifdef TARGET_NR_clock_gettime
     case TARGET_NR_clock_gettime:
     {
@@ -11469,6 +11497,17 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
         return ret;
     }
 #endif
+#ifdef TARGET_NR_clock_gettime64
+    case TARGET_NR_clock_gettime64:
+    {
+        struct timespec ts;
+        ret = get_errno(clock_gettime(arg1, &ts));
+        if (!is_error(ret)) {
+            ret = host_to_target_timespec64(arg2, &ts);
+        }
+        return ret;
+    }
+#endif
 #ifdef TARGET_NR_clock_getres
     case TARGET_NR_clock_getres:
     {
-- 
2.25.1