OSDUpdateLocker Class Reference

#include <osdtypeteletext.h>

Detailed Description

Helper class to the OSDTypeTeletext.

This class is used to lock the m_lock semaphore when there is a chance that the locked code will result in the OSD::UpdateTeletext() function being called. It's purpose is to lock the semaphore and once the locked code has finished to check for a request to call OSD::UpdateTeletext(). If required, the m_lock is released and the required call made

This is to overcome the possible semaphore deadlock as follows:

   - Teletext data arrives -> locks m_lock
   - While the teletext data is being processed the XMV request an
     OSD update display
   - The OSD update display will lock the osdlock
   - The OSD update can results in the Teletext:Draw method being
     called and hence the OSD update is now waiting on m_lock being
     released to continue it's drawing process
   - If the processing of the teletext data result in the function
     OSD::UpdateTeletext being called, this function will try to
     get the osdlock.
   - This results in the classic semaphore deadlock and hence all
     OSD update cease.

Definition at line 109 of file osdtypeteletext.h.


Public Member Functions
	OSDUpdateLocker (QMutex lock, OSDTypeTeletext parent)
	~OSDUpdateLocker (void)
Private Attributes
QMutex *	m_lock
OSDTypeTeletext *	m_parent