Fix dup for /dev/dsp

Corinna Vinschen
Mon Jul 19 11:45:00 GMT 2004

On Jul 18 18:11, Gerd Spalink wrote:
> What I did:
> The static open_count is no longer needed because now we consistently
> use the return status from the windows API to decide if we can open or not.
> This change is not related to dup.
> Wave header parsing needed a small fix. It was a +/-1 problem.
> To fix all cases of dup, a dup_chain is maintained to keep all duped instances
> consistent. I did not understand how to apply archetypes for this problem,
> and this solution works (test suite contribution is in separate patch).

Well... don't get me wrong but the doubely linked list looks a bit overly
complicated to me.  What is the problem you have with the archetype idea?
Did you have a look into fhandler_tty_slave::open/close/dup?  The archetype
really just adds a few lines of code and seems pretty straightforward to me.

Other than that, the code looks ok to me.  But I really think you should
give the archetype idea another try.


> ChangeLog:
> 2004-07-18 Gerd Spalink <>
> 	* fhandler.h (class fhandler_dev_dsp): Remove static open_count,
> 	add members to keep track of duped instances.
> 	* (fhandler_dev_dsp::Audio_out::parsewav): Compare
> 	with <= end for the case that only the header is passed to write.
> 	(fhandler_dev_dsp::fhandler_dev_dsp): Initialize new members
> 	dup_chain_next and dup_chain_prev.
> 	(fhandler_dev_dsp::open): Remove open_count; instead of query use
> 	start/stop to get wave device status from win32.
> 	(fhandler_dev_dsp::write): Insert call to update_duped.
> 	(fhandler_dev_dsp::close): Check dup_chain before stop of audio
> 	device.
> 	(fhandler_dev_dsp::dup): Create dup_chain linked list. Copy members
> 	by calling dup_cpy.
> 	(fhandler_dev_dsp::dup_cpy): New.
> 	(fhandler_dev_dsp::update_duped): New.
> 	(fhandler_dev_dsp::ioctl): Replace all inline return statements by
> 	setting variable rc. At the end, reflect any changes in duped instances
> 	by calling update_duped ().

Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Co-Project Leader
Red Hat, Inc.

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