[PATCH] convert udevsend/udevd to DGRAM and single-threaded

[PATCH] convert udevsend/udevd to DGRAM and single-threaded

On Fri, Feb 06, 2004 at 01:08:24AM -0500, Chris Friesen wrote:
>
> Kay, you said "unless we can get rid of _all_ the threads or at least
> getting faster, I don't want to change it."
>
> Well how about we get rid of all the threads, *and* we get faster?

Yes, we are twice as fast now on my box :)

> This patch applies to current bk trees, and does the following:
>
> 1) Switch to DGRAM sockets rather than STREAM.  This simplifies things
> as mentioned in the previous message.
>
> 2) Invalid sequence numbers are mapped to -1 rather than zero, since
> zero is a valid sequence number (I think).  Also, this allows for real
> speed tests using scripts starting at a zero sequence number, since that
> is what the initial expected sequence number is.
>
> 3) Get rid of all threading.  This is the biggie.  Some highlights:
> 	a) timeout using setitimer() and SIGALRM
> 	b) async child death notification via SIGCHLD
> 	c) these two signal handlers do nothing but raise volatile flags,
> 	all the
> work is done in the main loop
> 	d) locking no longer required

I cleaned up the rest of the comments, the whitespace and a few names to match
the whole thing. Please recheck it. Test script is switched to work on subsystem
'test' to let udev ignore it.