Message-ID: <5d6b657504091608511f100109@mail.gmail.com>
Date: Thu, 16 Sep 2004 17:51:04 +0200
From: Buddy Lucas <buddy.lucas@gmail.com>
Reply-To: Buddy Lucas <buddy.lucas@gmail.com>
To: Stelian Pop <stelian@popies.net>, Buddy Lucas <buddy.lucas@gmail.com>,
       Andrew Morton <akpm@osdl.org>, linux-kernel@vger.kernel.org
Subject: Re: [RFC, 2.6] a simple FIFO implementation
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On Thu, 16 Sep 2004 17:29:19 +0200, Stelian Pop <stelian@popies.net> wrote:
> On Thu, Sep 16, 2004 at 05:09:51PM +0200, Buddy Lucas wrote:
> 
> > > +       total = remaining = min(len, fifo->size - fifo->tail + fifo->head);
> >
> > I could be mistaken (long day at the office ;-) but doesn't this fail after
> > wrapping?
> 
> No, because the type is *unsigned* int.

Indeed, that would exactly be the reason *why* this would fail. ;-) 

The expression fifo->size - fifo->tail + fifo->head might be negative
at some point, right? (fifo->head has wrapped to some small value and
fifo->tail > fifo->size)


Cheers,
Buddy

> 
> Stelian.
> --
> 
> 
> Stelian Pop <stelian@popies.net>
>
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