Method store_if_not_there

libcppcryptfs/filename/longfilenamecache.cpp:177–238

bool LongFilenameCache::store_if_not_there(LPCWSTR base64_hash, LPCWSTR path, const char *actual_encrypted)
{

	bool rval = true;

	const WCHAR *key = base64_hash;

	lock();

	try {

		// see if it's already there.  If it isn't, inser it.
		
		// If it is already there THEN DO NOTHING

		auto mp = m_map.emplace(key, (LongFilenameCacheNode*)NULL);		

		if (mp.second) {

			LongFilenameCacheNode *node = NULL;

			// if it isn't, then see if the cache is full
			
			// if so, remove oldest entry (from tail of linked list)
			
			if (m_map.size() >= LFN_CACHE_ENTRIES) {
				node = m_lru_list.back();
				m_lru_list.pop_back();
				m_map.erase(node->m_key);
			}

			// re-use node if we removed one, otherwise get one from spare list, otherwise make a new one

			if (!node) {
				if (!m_spare_node_list.empty()) {
					node = m_spare_node_list.front();
					m_spare_node_list.pop_front();
				} else {
					node = new LongFilenameCacheNode;
				}
			}

			mp.first->second = node;

			node->m_key = mp.first->first;
			node->m_path = path;
			node->m_actual_encrypted = actual_encrypted;
#ifndef LFN_CACHE_NOTTL
			node->m_timestap = GetTickCount64();
#endif
			node->m_list_it = m_lru_list.insert(m_lru_list.begin(), node);
			
		}

	} catch (...) {
		rval = false;
	}