function onLoad() {
  update(document.getElementById('title'), 'title_dst');
  update_url(document.getElementById('url'), 'url_dst');
  update(document.getElementById('descr'), 'descr_dst');
}

function validateForm(form) {
  if (form.linkpage.value.length < 7) {
    alert("Step 2: URL -> missing or invalid\n" +
          "A valid example: http://www.mysite.com/links.html");
    return false;
  }

  if (form.title.value.length <= 0) {
    alert("Step 3: Title -> missing");
    return false;
  }

  if (form.url.value.length <= 7) {
    alert("Step 3: URL -> missing or invalid\n" +
          "A valid example: http://www.mysite.com/");
    return false;
  }

  if (form.descr.value.length <= 10) {
    alert("Step 3: Description -> missing or too short");
    return false;
  }

  if (form.descr.value.length > 500) {
    alert("Step 3: Description -> too long (" + 
          form.descr.value.length + " characters).\n" + 
          "Please edit it to keep it below 500 characters.");
    return false;
  }

  return true;
}

function update(src, dst) {
  document.getElementById(dst).innerHTML = src.value;
}

function update_url(src, dst) {
  document.getElementById(dst).href = src.value;
}