From owner-freebsd-hackers  Wed Feb 12 01:45:34 1997
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Date: Wed, 12 Feb 1997 20:45:17 +1100
From: David Nugent <davidn@labs.usn.blaze.net.au>
To: "Daniel O'Callaghan" <danny@panda.hilink.com.au>
Cc: hackers@freebsd.org
Subject: Re: strlen() question
References: <Pine.BSF.3.91.970212175317.427s-100000@panda.hilink.com.au>
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In-Reply-To: <Pine.BSF.3.91.970212175317.427s-100000@panda.hilink.com.au>; from Daniel O'Callaghan on Feb 02, 1997 at 06:04:59PM
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On Feb 02, 1997 at 06:04:59PM, Daniel O'Callaghan wrote:
> Below is the code for strlen() from libc.  It is extremely simple, and
> fast. Is it really safe to assume that strlen() will never exceed process
> memory bounds before striking a '\0'?

This is the programmer's responsibility.


> Or should there be a strnlen() function in libc for checking the
> length of suspicious strings? 

No. FWIW, you can use memchr(3) for that.


Regards,

David Nugent - Unique Computing Pty Ltd - Melbourne, Australia
Voice +61-3-9791-9547  Data/BBS +61-3-9792-3507  3:632/348@fidonet
davidn@freebsd.org davidn@blaze.net.au http://www.blaze.net.au/~davidn/