Re: [xml] Building libxml2 as a DLL under MinGW MSYS

[jhheider attbi com]

> On Tue, Sep 24, 2002 at 04:21:13PM +0000, 
jhheider attbi com wrote:
> > When I build libxml as a DLL using the
> > win32/Makefile.mingw, I get errors indicating that 
the 
> > code I'm using can't find _imp__xmlFree. A co-worker 
and
> > I are using libxml with Peter Jones's xmlwrapp C++
> > wrapper (http://pmade.org/pjones/software/xmlwrapp/)
> > and we came up with a way to build the system with 
only
> > minor changes to source files. I'm not as familar as 
I'd
> > like to be with the autotools for configuration, so 
this
> > can probably be improved, but these changes do allow 
us
> > to build a dll that works with xmlwrapp. These 
changes
> > are against the 2.4.24 source using the MSYS 
environment
> > from the MinGW folks 
(http://www.mingw.org/msys.shtml).
> > Hope this helps.
> >
> > Please let me know if I can be of further assistance
> > getting these changes integrated.
>
>    What do they do ? A patch without explanation of 
what it's
> supposed to do has little chances to get in. Give 
details please !
> Daniel

Of course. By file:

include/libxml/entities.h
include/libxml/parser.h
  - Added 'LIBXML_DLL_IMPORT' to all function definitions
    for replacement with __declspec(dllimport) or 
    __declspec(dllexport) as needed.

include/libxml/tree.h
  - Same as above
  - Replaced
#if defined(WIN32) && (defined(_MSC_VER) || defined
(__BORLANDC__))
    with
#if defined(__WIN32__)
    since MinGW compiler doesn't define either of these.

include/libxml/xmlversion.h
  - disabled libiconv

include/win32config.h
  - changed an 
#ifdef _MSC_VER
    to
#if defined(_MSC_VER) || defined(__MINGW32__)
  - expanded 'LIBXML_DLL_IMPORT' logic to set both
    __declspec(dllimport) and __declspec(dllexport)
    as appropriate.

configure
  - added a block to set NEED_TRIO, LDFLAGS, and CPPFLAGS
    appropriately for MINGW32. Also added an 
    ADDIITIONAL_DLL_COMMANDS replacement to insert dll
    commands in the makefile.

trio.h
  - modified this block
#if defined(WIN32) && !defined(isascii)
# define isascii ((unsigned)(x) < 0x80)
#endif
    by inserting '0 &&' after '#if'. It looks like 'x'
    should be a macro arguement, and gcc seems to have no
    problem without this.

Makefile.in
  - Added '@ADDITIONAL_DLL_COMMANDS@' for insertion of
    additional calls.

I realize that not all of the changes may require
modification so as to not change any already existing
functionality, but as they stand, they comprise a 
sufficient set to allow one to build libxml under MSYS.