check if clsss's style is valid when clearing the pen

[assefa]

Latest changes in MapServer with class and styles initialisation were causing MapServer to crash while drawing 24bis images into 8bit output. I have done the same test with the 4.10.x and there is no issue with it.

--- mapdrawgdal.c (revision 6087)

+++ mapdrawgdal.c (working copy)

@@ -577,8 +577,12 @@

if( gdImg && !truecolor ) {

int iClass;

+ int iStyle;

for( iClass = 0; iClass < layer->numclasses; iClass++ )

• layer->class[iClass]->styles[0]->color.pen = MS_PEN_UNSET;

+ { + for (iStyle=0; iStyle<layer->class[iClass]->numstyles; iStyle++) + layer->class[iClass]->styles[iStyle]->color.pen = MS_PEN_UNSET; + }

}

[assefa]

fixed in main trunck r6096