extmod/vfs: Support larger integer range in VFS stat time fields.

On ports like unix where the Epoch is 1970/1/1 and atime/mtime/ctime are in
seconds since the Epoch, this value will overflow a small-int on 32-bit
systems.  So far this is only an issue on 32-bit unix builds that use the
VFS layer (eg dev and coverage unix variants) but the fix (using
mp_obj_new_int_from_uint instead of MP_OBJ_NEW_SMALL_INT) is there for all
ports so as to not complicate the code, and because they will need the
range one day.

Also apply a similar fix to other fields in VfsPosix.stat because they may
also be large.
Signed-off-by: Damien George <damien@micropython.org>

extmod/vfs_fat.c

@@ -326,9 +326,9 @@ STATIC mp_obj_t fat_vfs_stat(mp_obj_t vfs_in, mp_obj_t path_in) {
     t->items[4] = MP_OBJ_NEW_SMALL_INT(0); // st_uid
     t->items[5] = MP_OBJ_NEW_SMALL_INT(0); // st_gid
     t->items[6] = mp_obj_new_int_from_uint(fno.fsize); // st_size
-    t->items[7] = MP_OBJ_NEW_SMALL_INT(seconds); // st_atime
-    t->items[8] = MP_OBJ_NEW_SMALL_INT(seconds); // st_mtime
-    t->items[9] = MP_OBJ_NEW_SMALL_INT(seconds); // st_ctime
+    t->items[7] = mp_obj_new_int_from_uint(seconds); // st_atime
+    t->items[8] = mp_obj_new_int_from_uint(seconds); // st_mtime
+    t->items[9] = mp_obj_new_int_from_uint(seconds); // st_ctime
 
     return MP_OBJ_FROM_PTR(t);
 }

extmod/vfs_lfsx.c

@@ -377,9 +377,9 @@ STATIC mp_obj_t MP_VFS_LFSx(stat)(mp_obj_t self_in, mp_obj_t path_in) {
     t->items[4] = MP_OBJ_NEW_SMALL_INT(0); // st_uid
     t->items[5] = MP_OBJ_NEW_SMALL_INT(0); // st_gid
     t->items[6] = mp_obj_new_int_from_uint(info.size); // st_size
-    t->items[7] = MP_OBJ_NEW_SMALL_INT(mtime); // st_atime
-    t->items[8] = MP_OBJ_NEW_SMALL_INT(mtime); // st_mtime
-    t->items[9] = MP_OBJ_NEW_SMALL_INT(mtime); // st_ctime
+    t->items[7] = mp_obj_new_int_from_uint(mtime); // st_atime
+    t->items[8] = mp_obj_new_int_from_uint(mtime); // st_mtime
+    t->items[9] = mp_obj_new_int_from_uint(mtime); // st_ctime
 
     return MP_OBJ_FROM_PTR(t);
 }

extmod/vfs_posix.c

@@ -295,15 +295,15 @@ STATIC mp_obj_t vfs_posix_stat(mp_obj_t self_in, mp_obj_t path_in) {
     MP_HAL_RETRY_SYSCALL(ret, stat(path, &sb), mp_raise_OSError(err));
     mp_obj_tuple_t *t = MP_OBJ_TO_PTR(mp_obj_new_tuple(10, NULL));
     t->items[0] = MP_OBJ_NEW_SMALL_INT(sb.st_mode);
-    t->items[1] = MP_OBJ_NEW_SMALL_INT(sb.st_ino);
-    t->items[2] = MP_OBJ_NEW_SMALL_INT(sb.st_dev);
-    t->items[3] = MP_OBJ_NEW_SMALL_INT(sb.st_nlink);
-    t->items[4] = MP_OBJ_NEW_SMALL_INT(sb.st_uid);
-    t->items[5] = MP_OBJ_NEW_SMALL_INT(sb.st_gid);
-    t->items[6] = MP_OBJ_NEW_SMALL_INT(sb.st_size);
-    t->items[7] = MP_OBJ_NEW_SMALL_INT(sb.st_atime);
-    t->items[8] = MP_OBJ_NEW_SMALL_INT(sb.st_mtime);
-    t->items[9] = MP_OBJ_NEW_SMALL_INT(sb.st_ctime);
+    t->items[1] = mp_obj_new_int_from_uint(sb.st_ino);
+    t->items[2] = mp_obj_new_int_from_uint(sb.st_dev);
+    t->items[3] = mp_obj_new_int_from_uint(sb.st_nlink);
+    t->items[4] = mp_obj_new_int_from_uint(sb.st_uid);
+    t->items[5] = mp_obj_new_int_from_uint(sb.st_gid);
+    t->items[6] = mp_obj_new_int_from_uint(sb.st_size);
+    t->items[7] = mp_obj_new_int_from_uint(sb.st_atime);
+    t->items[8] = mp_obj_new_int_from_uint(sb.st_mtime);
+    t->items[9] = mp_obj_new_int_from_uint(sb.st_ctime);
     return MP_OBJ_FROM_PTR(t);
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_2(vfs_posix_stat_obj, vfs_posix_stat);