I have a Drupal 7 custom form where the image or file field is not required. When the form is submitted and no file/image has been uploaded, I get the following errors.

Notice: Undefined index: storage in jobform_my_form_submit() (line 136 of /var/www/html/drupaltst/sites/all/modules/jobpackage/jobform.module).
Warning: Creating default object from empty value in jobform_my_form_submit() (line 141 of var/www/html/drupaltst/sites/all/modules/jobpackage/jobform.module). Notice: Undefined property: stdClass::$uri in file_save() (line 601 of /var/www/html/drupaltst/includes/file.inc).

Any help is appreciated!

function jobform_permission() {   return array(     'add jobs module' => array(        'title' => t('Administer permission for your module'),        'description' => t('Some description that would appear on the permission page..'),     ),   ); }  function jobform_menu() {   $items = array();   //$items['jobform/form'] = array(   $items['jobform'] = array(     'title' => t('Job Form Details'),     'page callback' => 'jobform_form',     'page arguments' => array('jobform_form'),     'access arguments' => array('add jobs module'),     'description' => t('My form'),     'type' => MENU_CALLBACK,   );   return $items; }      function jobform_form() {   return drupal_get_form('jobform_my_form'); }   function jobform_my_form($form, &$form_state) {   $form['title'] = array(     '#type' => 'textfield',     '#title' => t('Title'),     '#required' => TRUE,     '#maxlength' => 100,     '#prefix' => '<div class="titletle"><img src="/drupaltst/sites/default/files/images/title_icon.png" height="50" width="45">',       '#suffix' => '</img></div>',      '#attributes' => array(        'placeholder' => t('Enter a Short Title'),      ),     );        $form['descr'] = array(      '#type' => 'textarea',      '#title' => t('Description'),      '#required' => TRUE,      '#size' => 150,      '#maxlength' => 5000,      '#prefix' => '<div class="titledescr"><img src="/drupaltst/sites/default/files/images/descr_req_icon.png" height="50" width="45">',       '#suffix' => '</img></div>',      '#attributes' => array(        'placeholder' => t('Enter some specific details about the service you provide!'),      ),     );           $form['location'] = array(      '#type' => 'textfield',      '#title' => t('Enter Your Location'),      '#required' => TRUE,      '#size' => 75,      '#prefix' => '<div class="titleloc"><img src="/drupaltst/sites/default/files/images/loc_icon.png" height="50" width="41">',       '#suffix' => '</img></div>',      '#attributes' => array(       'placeholder' => t('Where Can the Work Be Completed? (i.e. Online, City, State, Zip)'),      ),        );             //Image Field    $form['image'] = array(      '#type' => 'file',      '#title' => t('Upload a Photo'),      '#description' => t('Allowed extensions: gif png jpg jpeg'),      '#prefix' => '<br><div class="titlefile"><img src="/drupaltst/sites/default/files/images/upload_image_icon.png" height="50" width="41">',       '#suffix' => '</img></div>',    );    $form['submit'] = array(      '#type' => 'submit',      '#value' => 'Submit',      '#prefix' => '<br><div class="titlesubmit">',       '#suffix' => '</div>',    );           return $form;  }   function jobform_my_form_validate($form, &$form_state) {    $file = file_save_upload('image', array(      // Validates file is really an image.      'file_validate_is_image' => array(),      // Validate extensions.      'file_validate_extensions' => array('png gif jpg jpeg'),    ));    // If the file passed validation:    if ($file) {      // Move the file into the Drupal file system.      if ($file = file_move($file, 'public://images/')) {        // Save the file for use in the submit handler.        //$form_state['image'] = $file;        $form_state['storage']['image'] = $file;      }      else {        form_set_error('image', t("Failed to write the uploaded file to the site's file folder."));      }    }     else {      form_set_error('image', t('No file was uploaded.'));      //$file = file_move($file, 'public://images/title_icon.png');    }  }      function jobform_my_form_submit($form, $form_state) {        $file = $form_state['storage']['image'];    // We are done with the file, remove it from storage.    //unset($form_state['image']);    unset($form_state['storage']['image']);    // Make the storage of the file permanent.    $file->status = FILE_STATUS_PERMANENT;    // Save file status.    file_save($file);    global $user;     $na = 0;    $istat = 1;    db_insert('job_mp_catalog')      ->fields(array(        'user_id' => $user->uid,        'title' => $form_state['values']['title'],        'descr' => $form_state['values']['descr'],        'location' => $form_state['values']['location'],        'image' => $file->fid,))      ->execute();         drupal_set_message("successfully saved ");    //Example:    //drupal_goto("user/".$user->uid."/edit");    drupal_goto("content/test-page");    //drupal_set_message("successfully saved Job!");  }