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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Based on my reading of the Plugin Writer’s Guide &
the GstElement reference docs, elements are supposed to complete all of their
deallocation on the READY -> NULL transition. However, it’s always
bothered me that there’s a case where you could still get a memory leak.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Suppose an element’s GObjectClass.set_property() gets
called while the element is still in the NULL state. If this property
accepts a string or some other type of heap-allocated object, the element is
probably going to create a copy or add a ref. Now, suppose some problem occurs
and the element is disposed before ever going to the READY state. There
will be no transition back to NULL. Therefore, the only possibility of
deallocating the value is by overriding GstObjetClass.dispose().<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I concede that this isn’t normally an issue, since the
size of any such properties is likely to be very small and many applications
will either exit or typically repeat this sequence a limited number of times.
However, it’s quite possible that some sort of automated recording
application might repeat this sequence somewhat rapidly and for an indefinite
period of time.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Then, there’s the whole philosophical issue of
avoiding even small leaks, which turns into a very practical issue when trying
to use tools to find slightly more serious leaks. I know you can usually
work around this, through the use of filtering, but it’s inconvenient and
not always satisfactory… let’s please try to avoid a flame war
about this.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Would it be so bad for GstObjectClass and GstElementClass to
at least provide a dispose() hook? I’m aware that I could just save
the old value & replace with my own dispose(), but something feels wrong
about having the derived type dispose of its ancestors. It’s also
not a very user-friendly way to do it, since there are numerous ways the
derived type can mess things up (i.e. not saving the old value or failing to call
it last).<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Matt<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
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