Ticket #4642: invalidated-iterator

List iterators can become invalidated by executing on them.

From: Erik Hovland <erik@hovland.org>

If they are then used in testing they may behave correctly. But
it is likely that the behavior is undefined and the invalidated
iterator can actually cause a segfault if accessed.

This patch addresses an instance where a iterator is invalidated
and is then tested.
---

 libs/libmythtv/firewiredevice.cpp |    7 +++----
 1 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/libs/libmythtv/firewiredevice.cpp b/libs/libmythtv/firewiredevice.cpp
index 52f7f9c..8abda84 100644
--- a/libs/libmythtv/firewiredevice.cpp
+++ b/libs/libmythtv/firewiredevice.cpp
@@ -49,13 +49,12 @@ void FirewireDevice::RemoveListener(TSDataListener *listener)
 {
     vector<TSDataListener*>::iterator it = m_listeners.end();
 
-    do
+    for (it = find(m_listeners.begin(), m_listeners.end(), listener);
+         it != m_listeners.end();)
     {
+        m_listeners.erase(it);
         it = find(m_listeners.begin(), m_listeners.end(), listener);
-        if (it != m_listeners.end())
-            m_listeners.erase(it);
     }
-    while (it != m_listeners.end());
 
     VERBOSE(VB_RECORD, LOC + "RemoveListener() "<<m_listeners.size());
 }