syscall_fs3: correct EROFS handling for devices on a read-only fs

With this you can now boot up into a shell with r/o root so once we fix up
the native fsck to do fuzix and fit in the memory space you'll be able to
rescue the root fs natively

diff --git a/Kernel/syscall_fs3.c b/Kernel/syscall_fs3.c
index 06a2b9f..5fccbeb 100644 (file)
--- a/Kernel/syscall_fs3.c
+++ b/Kernel/syscall_fs3.c
@@ -86,7 +86,9 @@ arg_t _open(void)
                        udata.u_error = EISDIR;
                        goto cantopen;
                }
-               if (ino->c_flags & CRDONLY) {
+               /* Special case - devices on a read only file system may
+                  be opened read/write */
+               if (!isdevice(ino) && (ino->c_flags & CRDONLY)) {
                        udata.u_error = EROFS;
                        goto cantopen;
                }