Mapserver compilation flags should be added to the SWIG command line

Thu Aug 31 06:34:45 EDT 2006

Tamas,
I have reviewed all the .h files included in mapscript.i and I have
found that there are only a few unsafe usages of defines (and they
refer to the usual suspects, that is z/m members for points and geos).

In mapprimitive.h

line 74 (Definitely UNSAFE!!)
#ifdef USE_POINT_Z_M
  double z;
  double m;
#endif

line 100 (UNSAFE, but fixable):
#ifdef USE_GEOS
  void *geometry;
#endif

Other suspicious usages could be in mapows.h, but at this time I am
not sure whether they are actually posing a problem.

I don't see an easy solution to the z/m defines, but I attach a patch
that removes the need for #ifdef USE_GEOS in mapprimitive.h. I have
made a couple of tests and it seems ok to me, but I want your valuable
feedback and Steve's approval before I commit it.

Umberto

On 8/31/06, Tamas Szekeres <szekerest at gmail.com> wrote:
> Hi Umberto,
>
> How your proposal will prevent from the need of settings the defines to SWIG?
> We have ifdefs in some of the headers (eg. in map.h) will continue to
> affect the interface generation.
>
> Tamas
>
>
>
> 2006/8/31, Umberto Nicoletti <umberto.nicoletti at gmail.com>:
> > Hi Tamas,
> >
> > On 8/30/06, Tamas Szekeres <szekerest at gmail.com> wrote:
> > > Umberto,
> > >
> > > I guess your proposal was to replace the affected functions from the
> > > interface files to the core mapserver code, correct me if I am wrong.
> >
> > You are right.
> >
> > > But I still can't understand what's the problem with adding the
> > > preprocessor defines to the SWIG command line. It requires to change
> > > only a line in the makefile.
> >
> > Only Java and c# have makefiles. Perl, python, tcl don't.
> > Keeping preprocessor defines out of the interface files was a design
> > decision taken a long time ago and (almost) always enforced. In fact
> > there aren't other defines in all the rest of the swig interface
> > files.
> >
> > Umberto
> >
> > >
> > > Tamas
> > >
> > >
> > >
> > > 2006/8/30, Umberto Nicoletti <umberto.nicoletti at gmail.com>:
> > > > Hi Steve,
> > > > While doing the usual house keeping before 4.10 gets out I have looked
> > > > at the source of the swig interface files and found that they contain
> > > > preprocessor defines (#ifdef USE_GEOS for example).
> > > > Most of the mapscript laguages will ignore these defines because swig
> > > > is not passed the list of options built by configure. Java mapscript
> > > > used to pass the list to swig, but this feature was removed a long
> > > > time ago because Sean opted for removing the preprocessor defines from
> > > > the swig interface files to keep them tidier.
> > > > C# mapscript at this point is the only laguage still passing defines to swig.
> > > > Perl, Ruby and Python invoke swig without passing the defines; also,
> > > > in the case of Perl and Python swig must be run manually by the user
> > > > (by typing the right command in the shell).
> > > >
> > > > Now since most mapscript will ignore those preprocessor defines we are
> > > > facing a potentially critical issue and, in the case of GEOS,
> > > > mapscript won't use some GEOS functions.
> > > > Other possible errors could be memory errors due to the use of non
> > > > initialized variables (this is the case of POINT_Z_M).
> > > >
> > > > I have reviewed the swig interface files and found these possibly
> > > > harmful defines:
> > > >
> > > > swiginc/image.i:#if GD2_VERS > 1
> > > >
> > > > Not sure about this one, maybe it is right. Dunno where GD2_VERS is defined.
> > > >
> > > > swiginc/image.i:#ifdef USE_GD_GIF
> > > > swiginc/image.i:#ifdef USE_GD_PNG
> > > > swiginc/image.i:#ifdef USE_GD_JPEG
> > > > swiginc/image.i:#ifdef USE_GD_WBMP
> > > >
> > > > These were added by Sean in July 04 and should be removed, I guess.
> > > > They only affect TCL.
> > > >
> > > > swiginc/point.i:#ifdef USE_POINT_Z_M
> > > > swiginc/point.i:#ifdef USE_POINT_Z_M
> > > > swiginc/point.i:#ifdef USE_POINT_Z_M
> > > > swiginc/point.i:#ifdef USE_POINT_Z_M
> > > > swiginc/point.i:#ifdef USE_POINT_Z_M
> > > > swiginc/point.i:#ifdef USE_POINT_Z_M
> > > >
> > > > These are *rarely* used and they are not a real problem, at least for
> > > > 4.10. If used they crash Java mapscript for sure.
> > > >
> > > > swiginc/shape.i:#ifdef USE_GEOS
> > > > swiginc/shape.i:#ifdef USE_GEOS
> > > >
> > > > These were added by sdlime on his lates rework of geos code this june.
> > > > They should be moved out of the swig interface file into the c code of mapserver
> > > >
> > > > I hope I made myself clear,
> > > > Umberto
> > > >
> > > > On 8/28/06, Steve Lime <Steve.Lime at dnr.state.mn.us> wrote:
> > > > > Confused, what's the desired fix?
> > > > >
> > > > > >>> Umberto Nicoletti <umberto.nicoletti at GMAIL.COM> 8/28/2006 10:47:08
> > > > > AM >>>
> > > > > I have posted a similar mail today (search for Defines in swig
> > > > > interface files in the subject) . Tamas, sorry for the double posting,
> > > > > I missed this one.
> > > > >
> > > > > I appear to recall that it was once agreed that swig interface files
> > > > > should not have defines in them, but I at the moment the only
> > > > > reference I found is here:
> > > > >
> > > > > http://mapserver.gis.umn.edu/bugs/show_bug.cgi?id=895#c2
> > > > > (end of first para)
> > > > >
> > > > > Sean Gillies probably knows better.
> > > > >
> > > > > At this point C# is the only language that has 100% correct
> > > > > compilation today. Java mapscript had the flags passed to swig, but
> > > > > they were removed a long time ago.
> > > > > Other laguages like ruby and python require the user to generate the
> > > > > interface by running swig by hand. This makes it much difficult to
> > > > > pass defines to swig as the user should have to copy them from the
> > > > > Makefile or alternatively we should provide and mantain Makefiles for
> > > > > all mapscripts.
> > > > >
> > > > > This is the list of defines (still) in the swig interface files:
> > > > >
> > > > > swiginc/image.i:#if GD2_VERS > 1
> > > > >
> > > > > Not sure about this one, maybe it is right.....
> > > > >
> > > > > swiginc/image.i:#ifdef USE_GD_GIF
> > > > > swiginc/image.i:#ifdef USE_GD_PNG
> > > > > swiginc/image.i:#ifdef USE_GD_JPEG
> > > > > swiginc/image.i:#ifdef USE_GD_WBMP
> > > > >
> > > > > These were added by Sean in July 04.
> > > > >
> > > > > swiginc/point.i:#ifdef USE_POINT_Z_M
> > > > > swiginc/point.i:#ifdef USE_POINT_Z_M
> > > > > swiginc/point.i:#ifdef USE_POINT_Z_M
> > > > > swiginc/point.i:#ifdef USE_POINT_Z_M
> > > > > swiginc/point.i:#ifdef USE_POINT_Z_M
> > > > > swiginc/point.i:#ifdef USE_POINT_Z_M
> > > > >
> > > > > These are rarely used and they are not a real problem, at least for
> > > > > 4.10
> > > > >
> > > > > swiginc/shape.i:#ifdef USE_GEOS
> > > > > swiginc/shape.i:#ifdef USE_GEOS
> > > > >
> > > > > These were added by sdlime on his lates rework of geos code this june.
> > > > >
> > > > > I can try to take care of the defines in image.i and maybe steve of
> > > > > those in shape.i, but I dunno if I'm going or if we should do it for
> > > > > for 4.10?
> > > > >
> > > > > Umberto
> > > > >
> > > > >
> > > > > On 8/28/06, Daniel Morissette <dmorissette at mapgears.com> wrote:
> > > > > > Tamas Szekeres wrote:
> > > > > > > Folks,
> > > > > > >
> > > > > > > Currently most of the SWIG bindings does not add mapserver
> > > > > compilation
> > > > > > > flags to the
> > > > > > > SWIG command line and therefore the interface might not be
> > > > > generated
> > > > > > > properly.
> > > > > > > For example missing -DUSE_POINT_Z_M will prevent from generating z
> > > > > and m
> > > > > > > members
> > > > > > > for pointObj etc.
> > > > > > >
> > > > > > > I've added a bug for this issue:
> > > > > > > http://mapserver.gis.umn.edu/bugs/show_bug.cgi?id=1881
> > > > > > >
> > > > > > > And fixed for C#
> > > > > > >
> > > > > >
> > > > > > Does something need to be done for this for the other wrappers?
> > > > > There
> > > > > > used to be a 'mapscriptvars' file with all the compile flags used by
> > > > > the
> > > > > > Perl Makefile. Is this not used by the other bindings?
> > > > > >
> > > > > > Daniel
> > > > > > --
> > > > > > Daniel Morissette
> > > > > > http://www.mapgears.com/
> > > > > >
> > > > >
> > > >
> > >
> >
>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: patch-GEOS-defines.patch
Type: text/x-patch
Size: 1071 bytes
Desc: not available
Url : http://lists.osgeo.org/pipermail/mapserver-dev/attachments/20060831/c992a157/patch-GEOS-defines.bin