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Date: Fri, 22 Aug 2008 12:16:39 +0200
From: Luigi Rizzo <rizzo@iet.unipi.it>
To: Ivan Voras <ivoras@freebsd.org>
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Cc: freebsd-arch@freebsd.org
Subject: Re: Magic symlinks redux
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On Fri, Aug 22, 2008 at 11:59:07AM +0200, Ivan Voras wrote:
...
> >+ efficiency of symlink_magic() might be improved too:
> >  e.g. the function could do a quick check for the presence of @ and return
> >  without allocation/deallocation if not found;
> 
> I think it's because the author wanted a single pass over the string (in 
> case of the "extended" @{...} syntax we can't just check if cp[0] == 
> '@'). The first few lines of the symlink_magic loop ("if (cp[i] != 
> '@')") effectively do what strchr() does.

right, but doing the check upfront might save the uma_zalloc/zfree call
in the common case.

	cheers
	luigi