Re: [xml] libxml2 memory management and iconv

[Daniel Veillard <veillard redhat com>]

On Wed, Jan 10, 2007 at 05:59:23PM -0500, Tim Conkling wrote:
> I'm interested in compiling libxml2 for a videogame console that I'm working
> with (unfortunately, I'm contractually prevented from revealing the name of
> the particular console in question). In order to use libxml2 properly on
> this system, I need to supply it with my own memory management routines --
> calling malloc is an error.
>
> While making a build of the iconv library (I'm using the GNU iconv lib), I
> noticed that the iconv_open function calls malloc (and the corresponding
> function, iconv_close, calls free). libxml2 calls both of these functions.
>
> I'm not sure that I understand the whole picture here, but it _seems_ that
> libxml2 is making a promise to only use user-defined memory management
> routines if they are supplied, and then breaking that promise by calling an
> API that performs its own memory management.
>
> I'm looking for help in figuring out which of these statements is true:
>
> 1. libxml2's memory management design is broken, and the library's implicit
> guarantee to use user-supplied routines for memory management can't be
> relied on.
> 2. libxml2's memory management design is not broken; instead, libxml2
> assumes that a user who has specific memory management requirements will
> provide a version of the iconv API that meets these requirements.

  That one. Just compile without iconv supprt. Of course only a limited subset
of encodings will be supported, the XML-1.0 spec requires only UTF-8 and 
UTF-16, libxml2 also handle the ISO Latin x ones too natively. Read
    http://xmlsoft.org/encoding.html

> If #2 is the case, are there other external functions that libxml2 calls
> that may allocate their own memory, and that I should therefore supply my
> own implementation for?

  Not that I know of.

Daniel

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