telepathy-logger: log-iter-xml: Fix crash when logs are corrupted or invalid XML

[Debarshi Ray]

Module: telepathy-logger
Branch: master
Commit: 711842911edb15977430c0b6c1803e947619efc3
URL:    http://cgit.freedesktop.org/telepathy/telepathy-logger/commit/?id=711842911edb15977430c0b6c1803e947619efc3

Author: Debarshi Ray <debarshir at freedesktop.org>
Date:   Fri Apr 17 18:28:20 2015 +0200

log-iter-xml: Fix crash when logs are corrupted or invalid XML

Chances of _tpl_log_store_get_events_for_date returning NULL due to an
invalid XML file are lower because we ask libxml2 (since commit
734af80691) to recover from errors if possible. Even then, it doesn't
hurt to defend against this eventuality.

Thanks to Daniel Thompson for catching this!

https://bugs.freedesktop.org/show_bug.cgi?id=89595

---

 telepathy-logger/log-iter-xml.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/telepathy-logger/log-iter-xml.c b/telepathy-logger/log-iter-xml.c
index 1684a74..df531e4 100644
--- a/telepathy-logger/log-iter-xml.c
+++ b/telepathy-logger/log-iter-xml.c
@@ -81,8 +81,12 @@ tpl_log_iter_xml_get_events (TplLogIter *iter,
               priv->account, priv->target, priv->type_mask,
               (GDate *) priv->next_date->data);
 
-          priv->next_event = g_list_last (priv->events);
           priv->next_date = g_list_previous (priv->next_date);
+
+          if (priv->events == NULL)
+            continue;
+
+          priv->next_event = g_list_last (priv->events);
         }
 
       event = TPL_EVENT (priv->next_event->data);