[mapserver-users] HELP-Bug or Stupid Error on my part in MAPSERVER C API

[Scott Shealy]

Hey guys I have got a problem that I have been trying to figure out for over 
3 days now and was wondering if anyone else has any clues.

I am using the following Map File ....

---> begin Map file

NAME test
EXTENT -97.000 25.76 -88.049 31.00
SIZE 800 400
SHAPEPATH "/test_maps/base_cov"
IMAGECOLOR 0 0 204
SYMBOL
  NAME "circle"
  TYPE ellipse
  FILLED true
  POINTS 1 1 END
END

  LAYER
	NAME "query_wells"
	DATA "all_wells"
	STATUS ON
	TYPE POINT
	CLASS
		EXPRESSION ([api] EQ 42704400350000 OR [api] EQ 17101200790000)
		SYMBOL "circle"
		COLOR 0 0 0
		SIZE 5
	END
	TOLERANCEUNITS pixels
	TOLERANCE 20 
  END
END

<--- End Map file

I am using the following C program to demonstrate my problem

---> Begin c program

#include <stdlib.h>
#include "../../map.h"

int main(int argc,char *argv[]) {
	mapObj *m; 
	layerObj *l;
	int i,j,layernum,return_code,layer_num;
	gdImagePtr img;
	
	for(i=0; i<10;i++) {  
		printf("starting iteration %ld\n",i);
		m=msLoadMap("./test.map");
		if(m==NULL) {
			printf("error loading map on %ld iteration",i);
			exit(-1);
		}
		printf("Number of layers is %ld\n",m->numlayers);
		for( j=0;j<m->numlayers;j++) {
			printf("%s\n",m->layers[j].name);
		}

		img = msDrawMap(m);
		msSaveImage(img,"/tmp/xxx.png",m->imagetype,m->transparent,
			m->interlace,m->imagequality);
		msFreeImage(img);
		msFreeMap(m);

	}
	
	
}

<---  End C test program

When I run this program the first iteration of the main loop is ok and the 
genrated map image is correct...  But  the second iteration of the main loop 
fails at loading the map.  I stuck this thing in the debugger and when I 
enter msLoadMap on the second iteration everything is fine.  It appears to 
successfully open the map and then proceeds to parse the map file.  When the 
parser goes to get the first token it returns nothing and the msLoadMap 
function bails with an an error.  That definitely doesn't seem right but I 
can't figure out why it is bailing.  I can modify my setup two ways to make 
this problem go away but neither are acceptable but may provide some clues as 
to what is going on.

1) In my map file I can remove the EXPRESSION from the CLASS and everything 
runs fine... It goes through each iteration just fine and draws the map.

2)If I move the msLoadmap and msFreeMap() outside the main loop(ie only load 
the map once) everything works fine... even with the EXPRESSION Object in the 
map file. (But this won't work for me)

If I am using the mapserver C API correctly (thats a big if...please let me 
know if I am not) this sort of suggests to me  that there might be a bug in 
the cleaning up of resources associated with EXPRESSION Objects.

Other pertinant details include (using mapserver nightly build from 2 days 
ago(also used one from about a month ago with the same results)).

used this configure command

configure --with-proj --with-gdal

compile my test program with the following script
#!/bin/sh
FLAGS="-DUSE_PROJ -DUSE_PROJ_API_H -DUSE_GD_PNG -DUSE_GD_JPEG -DUSE_GD_WBMP 
-DUSE_GD_FT -DUSE_TIFF -DUSE_JPEG -DUSE_EPPL -DUSE_GDAL -DUSE_WMS 
-DIGNORE_MISSING_DATA"

gcc test2.c $FLAGS -g -L/usr/lib -lgd -ljpeg -lfreetype -lpng -lz -ltiff  
-L/usr/local/lib -lproj -lgdal.1.1 ../../libmap.a 

Any suggestion is greatly appreciated... meanwhile I will keep working on 
it...

Thanks,
Scott Shealy