/**
* Write single entry to the cache and to the database.
* Input:
* key = key with prefix
* val = value string
* Output:
* entry written to database
* cache updated
*/
private void WriteCache(string key, string val)
{
// write to database
using (MySqlCommand cmd = getCommand()) {
string command = "INSERT INTO ScriptDBs SET sdb_key=?sdbkey,sdb_val=?sdbval";
command += " ON DUPLICATE KEY UPDATE sdb_val=?sdbval";
cmd.CommandText = command;
cmd.Parameters.AddWithValue("?sdbkey", key);
cmd.Parameters.AddWithValue("?sdbval", val);
cmd.ExecuteNonQuery();
}
// remove from cache wherever it is
// make a new entry if not there already
ScriptDBCacheEntry entry;
if (m_Engine.m_ScriptDBCacheEntries.TryGetValue(key, out entry))
{
m_Engine.RemFromScriptDBCache(entry);
}
else
{
entry = new ScriptDBCacheEntry();
entry.sdbkey = key;
}
// update cache value
entry.sdbval = val;
// re-insert into cache as newest entry
m_Engine.AddToScriptDBCache(entry);
}
/**
* Read single element from database.
* Input:
* key = as given to xmrScriptDBWrite()
* notfound = value to return if not found
* Output:
* returns notfound: record not found
* else: value as given to xmrScriptDBWrite()
*/
public override string xmrScriptDBReadOne(string key, string notfound)
{
lock (m_Engine.m_ScriptDBLock) {
ScriptDBCacheEntry entry = ReadCache(getPrefix() + key);
return((entry.sdbval == null) ? notfound : entry.sdbval);
}
}
/**
* Read single entry from the cache (and database if not in cache).
* Input:
* key = key with prefix
* Output:
* returns cache entry (sdbval == null if record not found)
*/
private ScriptDBCacheEntry ReadCache(string key)
{
// remove from cache wherever it is
// create new entry if we don't already have one
ScriptDBCacheEntry entry;
if (m_Engine.m_ScriptDBCacheEntries.TryGetValue(key, out entry))
{
//?? optimization ??// if (entry.loaded == m_Engine.m_ScriptDBCacheSeq) return entry;
m_Engine.RemFromScriptDBCache(entry);
}
else
{
entry = new ScriptDBCacheEntry();
entry.sdbkey = key;
}
// make sure it was created at or after when this script was instanced so we know data isn't stale
if (entry.loaded < m_Instanced)
{
using (MySqlCommand cmd = getCommand()) {
cmd.CommandText = "SELECT sdb_val FROM ScriptDBs WHERE sdb_key=?sdbkey";
cmd.Parameters.AddWithValue("?sdbkey", key);
using (IDataReader rdr = cmd.ExecuteReader()) {
entry.sdbval = rdr.Read() ? rdr["sdb_val"].ToString() : null;
}
}
}
// add (back to) cache as the newest entry
m_Engine.AddToScriptDBCache(entry);
return(entry);
}
