+
+/*
+ External page call with saving current context.
+ $call - url of external page
+ $ctx - optional. name of SESSION context object or array of names of POST
+ variables saved on call
+*/
+function context_call($call, $ctx='')
+{
+ if (is_array($ctx))
+ {
+ foreach($ctx as $postname)
+ {
+ $context[$postname] = get_post($postname);
+ }
+ } else
+ $context = isset($_SESSION[$ctx]) ? $_SESSION[$ctx] : null;
+
+ array_unshift($_SESSION['Context'], array('name' => $ctx,
+ 'ctx' => $context,
+ 'caller' => $_SERVER['PHP_SELF'],
+ 'ret' => array()));
+ meta_forward($call);
+}
+/*
+ Restores context after external page call and
+ returns array of data passed by external page.
+*/
+function context_restore()
+{
+ if ( count($_SESSION['Context'])) {
+ if ($_SERVER['PHP_SELF'] == $_SESSION['Context'][0]['caller']) {
+ $ctx = array_shift($_SESSION['Context']);
+ if ($ctx) {
+ if (is_array($ctx['ctx'])) {
+ foreach($ctx['ctx'] as $name => $val)
+ {
+ $_POST[$name] = $val;
+ }
+ } else
+ if ($ctx['name']!='')
+ $_SESSION[$ctx['name']] = $ctx['ctx'];
+ return $ctx['ret'];
+ }
+ }
+ }
+ return false;
+}
+
+/*
+ Return to caller page if the page was called from external context.
+*/
+function context_return($ret)
+{
+ if ( count($_SESSION['Context'])) {
+ $ctx = &$_SESSION['Context'][0];
+ $ctx['ret'] = $ret;
+ meta_forward( $ctx['caller'] );
+ }
+}
+/*
+ Clearing context stack after page cancel.
+*/
+function context_reset()
+{
+ $_SESSION['Context'] = array();
+}
+
+/*
+ Context stack initialization
+*/
+if (!isset($_SESSION['Context'])) {
+ context_reset();
+}
+