From 39f978675a7efef5b7301b3edff76f54325b559b Mon Sep 17 00:00:00 2001
From: Mike Blumenkrantz <zmike@samsung.com>
Date: Fri, 23 Aug 2019 13:21:58 -0400
Subject: [PATCH] efl/io: fix race condition with child model deletion

Summary:
if an event is emitted for a child that is added to the model during a
call to _efl_io_model_children_list(), it's possible that this child
will never be detected by the model's monitor/sentry if it is deleted
before the monitor can detect it, which means there will never be a
corresponding eio event emitted

in this case, ensure that we manually remove this child from the model
since we know we've just deleted it

this fixes reliability issues with efl io model monitor unit test

@fix

Reviewers: cedric

Reviewed By: cedric

Subscribers: #reviewers, #committers

Tags: #efl

Differential Revision: https://phab.enlightenment.org/D9708
---
 src/lib/eio/efl_io_model.c | 43 ++++++++++++++++++++++----------------
 1 file changed, 25 insertions(+), 18 deletions(-)

diff --git a/src/lib/eio/efl_io_model.c b/src/lib/eio/efl_io_model.c
index 3383aac058..609958f485 100644
--- a/src/lib/eio/efl_io_model.c
+++ b/src/lib/eio/efl_io_model.c
@@ -154,37 +154,25 @@ _efl_model_evt_added_ecore_cb(void *data, int type, void *event)
    return EINA_TRUE;
 }
 
-static Eina_Bool
-_efl_model_evt_deleted_ecore_cb(void *data, int type, void *event)
+static void
+_model_child_remove(Efl_Io_Model_Data *pd, Eina_Stringshare *path)
 {
    Efl_Io_Model_Info *mi;
    Eina_List *l;
-   Eio_Monitor_Event *ev = event;
-   Efl_Io_Model *obj;
-   Efl_Io_Model_Data *pd = data;
-   Eina_Stringshare *spath = NULL;
+   Efl_Io_Model *obj = pd->self;
    Efl_Model_Children_Event cevt = { 0 };
    unsigned int i = 0;
 
-   if (type != EIO_MONITOR_DIRECTORY_DELETED && type != EIO_MONITOR_FILE_DELETED)
-     return EINA_TRUE;
-
-   if (ev->monitor != pd->monitor) return EINA_TRUE;
-
-   obj = pd->self;
-
-   spath = eina_stringshare_add(ev->filename);
-
    // FIXME: Linear search is pretty slow
    EINA_LIST_FOREACH(pd->files, l, mi)
      {
-        if (mi->path == spath)
+        if (mi->path == path)
           break ;
         ++i;
      }
 
    if (i >= eina_list_count(pd->files))
-     goto end;
+     return;
 
    cevt.index = i;
    cevt.child = mi->object;
@@ -197,8 +185,22 @@ _efl_model_evt_deleted_ecore_cb(void *data, int type, void *event)
 
    // This will only trigger the data destruction if no object is referencing them.
    _efl_io_model_info_free(mi, EINA_FALSE);
+}
 
- end:
+static Eina_Bool
+_efl_model_evt_deleted_ecore_cb(void *data, int type, void *event)
+{
+   Eio_Monitor_Event *ev = event;
+   Efl_Io_Model_Data *pd = data;
+   Eina_Stringshare *spath = NULL;
+
+   if (type != EIO_MONITOR_DIRECTORY_DELETED && type != EIO_MONITOR_FILE_DELETED)
+     return EINA_TRUE;
+
+   if (ev->monitor != pd->monitor) return EINA_TRUE;
+
+   spath = eina_stringshare_add(ev->filename);
+   _model_child_remove(pd, spath);
    eina_stringshare_del(spath);
 
    return EINA_TRUE;
@@ -221,7 +223,12 @@ static void
 _eio_done_unlink_cb(void *data, Eio_File *handler EINA_UNUSED)
 {
    Efl_Io_Model *child = data;
+   Efl_Io_Model_Data *child_pd, *pd;
 
+   child_pd = efl_data_scope_get(child, MY_CLASS);
+   pd = efl_data_scope_get(efl_parent_get(child), MY_CLASS);
+
+   _model_child_remove(pd, child_pd->path);
    _eio_del_cleanup(child);
 }