contrib/change_prefix.sh: don't run sed on binary files

contrib/src/change_prefix.sh

@@ -43,16 +43,20 @@ else
     new_prefix=$2
 fi
 
-# process [dir] [filemask]
+# process [dir] [filemask] [text only]
 process() {
     for file in `find $1 -maxdepth 1 -type f -name "$2"`
     do
+        if [ -n "$3" ]
+        then
+            file $file | sed "s/^.*: //" | grep -q 'text\|shell' || continue
+        fi
         echo "Fixing up $file"
         sed -i.orig -e "s,$old_prefix,$new_prefix,g" $file
         rm -f $file.orig
     done
 }
 
-process bin/ "*"
+process bin/ "*" check
 process lib/ "*.la"
 process lib/pkgconfig/ "*.pc"