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Date: Tue, 27 Mar 2012 10:23:56 +0200
From: Peter Rosin <peda AT lysator DOT liu DOT se>
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Subject: Re: rcs 5.8-1 checks out wrong version of file when using similar mark symbols
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Peter Rosin skrev 2012-03-27 10:11:
> But...careful!  You have to assume that the original authors were not
> idiots!  Maybe the obvious strcmp was not used for a *good* reason?  I
> can't tell if d->meaningful is guaranteed to be zero-terminated from the
> limited context, but it sure is suspect.  Assuming that the original
> authors were not idiots but instead made an off-by one error missing a
> corner-case, the safer approach is to replace line 11 with:
> 
> 11:        if (!strncmp (d->meaningful, id->string, id->size + 1))
> 
> That is, if id->string is guaranteed to be zero-terminated, which is
> not clear either, but perhaps easier to verify...

Scratch that, including the zero-terminator in the compare doesn't work
as expected if one of the strings is not zero-terminated.  But the point
still stands, don't assume the original authors were idiots, and dig
into the reasons for them to not having used strcmp from the start.

Cheers,
Peter

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