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Date: Sun, 19 May 2013 20:09:03 -0400
From: "Z. Gilboa" <>
To: <>
Subject: Re: patch: make the size of errbuf configurable

On 05/19/2013 07:22 PM, Rich Felker wrote:
> On Sun, May 19, 2013 at 06:26:04PM -0400, Z. Gilboa wrote:
>>>> In my understanding, the current approach of having a fixed buffer
>>>> size is by far the superior one.
>>> Could you elaborate as to why? Are you concerned about memory usage?
>>> Code complexity? Or some other reason?
>> A little bit of both, with complexity being the main factor.  As far
>> as I can tell (from looking at dynlink.c and otherwise), there is
>> only one case (do_relocs) where both the library name and symbol
>> name are sent to the buffer.  So given the case's rarity and
>> singularity, I would not introduce "complex" code or memory
>> allocation into the function.  We should also remember that this is
>> not about how the error is being handled, only about how it is being
>> presented, meaning that less code is probably better...
>  From what I can see, complexity can be avoided and maybe even reduced
> by refactoring the code so that all the places that set an error
> message call a short simple function that wraps snprintf and allocates
> a new buffer if needed. The complexity reduction would be if we can
> eliminate duplicate logic at each call point, which I haven't checked
> yet.
> Rich

When moving beyond dynlink.c then yes, I believe, that should be 
beneficial.  I just had a quick look at the places where snprintf is 
used, and found that the following functions might benefit from the 
above wrapper:

dynlink.c:    all functions that call snprintf
syslog.c:    _vsyslog
inet_ntop (unsure)
sem_open (unsure: _name_ can be up to 251 characters long 
(, but is link 
to _tmp_ which is only up to 64 characters long)


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