/**
  * Check if cache is valid, lock cache if required
  *
  * @param \Smarty_Internal_Template $_template
  *
  * @return bool flag true if cache is valid
  */
 public function isCached(Smarty_Internal_Template $_template)
 {
     if ($this->valid !== null) {
         return $this->valid;
     }
     while (true) {
         while (true) {
             if ($this->exists === false || $_template->smarty->force_compile || $_template->smarty->force_cache) {
                 $this->valid = false;
             } else {
                 $this->valid = true;
             }
             if ($this->valid && $_template->caching == Smarty::CACHING_LIFETIME_CURRENT && $_template->cache_lifetime >= 0 && time() > $this->timestamp + $_template->cache_lifetime) {
                 // lifetime expired
                 $this->valid = false;
             }
             if ($this->valid && $_template->smarty->compile_check == 1 && $_template->source->getTimeStamp() > $this->timestamp) {
                 $this->valid = false;
             }
             if ($this->valid || !$_template->smarty->cache_locking) {
                 break;
             }
             if (!$this->handler->locked($_template->smarty, $this)) {
                 $this->handler->acquireLock($_template->smarty, $this);
                 break 2;
             }
             $this->handler->populate($this, $_template);
         }
         if ($this->valid) {
             if (!$_template->smarty->cache_locking || $this->handler->locked($_template->smarty, $this) === null) {
                 // load cache file for the following checks
                 if ($_template->smarty->debugging) {
                     $_template->smarty->_debug->start_cache($_template);
                 }
                 if ($this->handler->process($_template, $this) === false) {
                     $this->valid = false;
                 } else {
                     $this->processed = true;
                 }
                 if ($_template->smarty->debugging) {
                     $_template->smarty->_debug->end_cache($_template);
                 }
             } else {
                 $this->is_locked = true;
                 continue;
             }
         } else {
             return $this->valid;
         }
         if ($this->valid && $_template->caching === Smarty::CACHING_LIFETIME_SAVED && $_template->cached->cache_lifetime >= 0 && time() > $_template->cached->timestamp + $_template->cached->cache_lifetime) {
             $this->valid = false;
         }
         if ($_template->smarty->cache_locking) {
             if (!$this->valid) {
                 $this->handler->acquireLock($_template->smarty, $this);
             } elseif ($this->is_locked) {
                 $this->handler->releaseLock($_template->smarty, $this);
             }
         }
         return $this->valid;
     }
     return $this->valid;
 }
 /**
  * Check if cache is valid, lock cache if required
  * @param \Smarty_Internal_Template $_template
  * @return bool flag true if cache is valid
  */
 public function isCached(Smarty_Internal_Template $_template)
 {
     if ($this->valid !== NULL) {
         return $this->valid;
     }
     while (TRUE) {
         while (TRUE) {
             if ($this->exists === FALSE || $_template->smarty->force_compile || $_template->smarty->force_cache) {
                 $this->valid = FALSE;
             } else {
                 $this->valid = TRUE;
             }
             if ($this->valid && $_template->caching == Smarty::CACHING_LIFETIME_CURRENT && $_template->cache_lifetime >= 0 && time() > $this->timestamp + $_template->cache_lifetime) {
                 // lifetime expired
                 $this->valid = FALSE;
             }
             if ($this->valid && $_template->source->timestamp > $this->timestamp) {
                 $this->valid = FALSE;
             }
             if ($this->valid || !$_template->smarty->cache_locking) {
                 break;
             }
             if (!$this->handler->locked($_template->smarty, $this)) {
                 $this->handler->acquireLock($_template->smarty, $this);
                 break 2;
             }
             $this->handler->populate($this, $_template);
         }
         if ($this->valid) {
             if (!$_template->smarty->cache_locking || $this->handler->locked($_template->smarty, $this) === NULL) {
                 // load cache file for the following checks
                 if ($_template->smarty->debugging) {
                     Smarty_Internal_Debug::start_cache($_template);
                 }
                 if ($this->handler->process($_template, $this) === FALSE) {
                     $this->valid = FALSE;
                 } else {
                     $this->processed = TRUE;
                 }
                 if ($_template->smarty->debugging) {
                     Smarty_Internal_Debug::end_cache($_template);
                 }
             } else {
                 $this->is_locked = TRUE;
                 continue;
             }
         } else {
             return $this->valid;
         }
         if ($this->valid && $_template->caching === Smarty::CACHING_LIFETIME_SAVED && $_template->properties['cache_lifetime'] >= 0 && time() > $_template->cached->timestamp + $_template->properties['cache_lifetime']) {
             $this->valid = FALSE;
         }
         if ($_template->smarty->cache_locking) {
             if (!$this->valid) {
                 $this->handler->acquireLock($_template->smarty, $this);
             } elseif ($this->is_locked) {
                 $this->handler->releaseLock($_template->smarty, $this);
             }
         }
         return $this->valid;
     }
     return $this->valid;
 }