linux-user: Use safe_syscall for read and write system calls

Restart read() and write() if signals occur before, or during with SA_RESTART

Signed-off-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Message-id: 1441497448-32489-15-git-send-email-T.E.Baldwin99@members.leeds.ac.uk
[PMM: Update to new safe_syscall() convention of setting errno]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index b6a8ed6..bee1360 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -707,6 +707,9 @@
     return safe_syscall(__NR_##name, arg1, arg2, arg3, arg4, arg5, arg6); \
 }
 
+safe_syscall3(ssize_t, read, int, fd, void *, buff, size_t, count)
+safe_syscall3(ssize_t, write, int, fd, const void *, buff, size_t, count)
+
 static inline int host_to_target_sock_type(int host_type)
 {
     int target_type;
@@ -5983,7 +5986,7 @@
         else {
             if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
                 goto efault;
-            ret = get_errno(read(arg1, p, arg3));
+            ret = get_errno(safe_read(arg1, p, arg3));
             if (ret >= 0 &&
                 fd_trans_host_to_target_data(arg1)) {
                 ret = fd_trans_host_to_target_data(arg1)(p, ret);
@@ -5994,7 +5997,7 @@
     case TARGET_NR_write:
         if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1)))
             goto efault;
-        ret = get_errno(write(arg1, p, arg3));
+        ret = get_errno(safe_write(arg1, p, arg3));
         unlock_user(p, arg2, 0);
         break;
 #ifdef TARGET_NR_open