save scroll state

index.html

@@ -72,6 +72,7 @@ function init() {
     document.getElementById("filter").focus();
     hitList=search_hits(document.getElementById("filter").value);
     print_results(hitList);
+    scroll_load();
 }
 function narrow_window() {
     return window.innerWidth < config.narrow;
@@ -280,7 +281,22 @@ function toggle_blank() {
   }
   arrow.innerHTML=arrowChar;
 }
+function scroll_save() {
+  document.cookie = "position=" + window.scrollY + ";";
+}
+function scroll_load() {
+  var nameEQ = "position=";
+  var ca = document.cookie.split(';');
+  position=0;
+  for(var i=0;i < ca.length;i++) {
+    var c = ca[i];
+    while (c.charAt(0)==' ') c = c.substring(1,c.length);
+    if (c.indexOf(nameEQ) == 0) { position=parseInt(c.substring(nameEQ.length,c.length)); break; }
+  }
+  window.scrollTo(0,position);
+}
 document.onkeyup=move_cursor;
+document.onscroll=scroll_save;
 var linkReg=/([^\[]*)\[([^\]]+)\]\(([^\)]+)\)(.*)/;
 var linkPlain=/(.*)(http[^\s]+)(.*)/;
 var linkList=[];