utime: Add the Unix API weirdnesses for utime(filename, NULL);

diff --git a/Kernel/syscall_fs2.c b/Kernel/syscall_fs2.c
index 3786cd8..2ee3aa9 100644 (file)
--- a/Kernel/syscall_fs2.c
+++ b/Kernel/syscall_fs2.c
@@ -309,15 +309,21 @@ int16_t _utime(void)
        inoptr ino;
        time_t t[2];
 
-       if (!valaddr(buf, 2 * sizeof(time_t)))
-               return (-1);
        if (!(ino = n_open(file, NULLINOPTR)))
                return (-1);
-       if (ino->c_node.i_uid != udata.u_euid && esuper()) {
-               i_deref(ino);
-               return (-1);
-       }
-       uget(buf, t, 2 * sizeof(time_t));
+       /* Special case in the Unix API - NULL means now */
+       if (buf) {
+               if (ino->c_node.i_uid != udata.u_euid && esuper())
+                       goto out;
+               if (!valaddr(buf, 2 * sizeof(time_t)))
+                       goto out2;
+               uget(buf, t, 2 * sizeof(time_t));
+       } else {
+               if (!(getperm(ino) & OTH_WR))
+                       goto out;
+               rdtime(&t[0]);
+               memcpy(&t[1], &t[0], sizeof(t[1]));
+        }
        /* FIXME: needs updating once we pack top bits
           elsewhere in the inode */
        ino->c_node.i_atime = t[0].low;
@@ -325,6 +331,11 @@ int16_t _utime(void)
        setftime(ino, C_TIME);
        i_deref(ino);
        return (0);
+out:
+       udata.u_error = EPERM;
+out2:
+       i_deref(ino);
+       return -1;
 }
 
 #undef file