// String and Binary handling. These are represented as a long, which is an offset into a file.
public long EncodeString( string s )
{
if ( s == "" ) return 0;
// See if it is in SysStringIndex
try
{
var start = new StringStart( s );
foreach( IndexFileRecord ixr in SysStringIndex.From( start.Compare, false ) )
{
if ( (string)(ixr.Col[0]._O) == s ) return ixr.Col[0].L;
break;
}
}
catch ( System.Exception x )
{
SysStringIndex.Dump();
throw x;
}
// Save to file.
long sid = SysString.Length;
SysString.Position = sid;
SysStringWriter.Write( s );
// Insert into the index
IndexFileRecord r = new IndexFileRecord( 1 );
r.Col[ 0 ].L = sid + 1;
r.Col[ 0 ]._O = s;
SysStringIndex.Insert( ref r );
return sid + 1; // + 1 because zero indicates the encoding has not yet been done.
}
/* Private methods */
void Commit( CommitStage c )
{
SysString.Commit( c );
SysBinary.Commit( c );
SysStringIndex.Commit( c );
SysBinaryIndex.Commit( c );
foreach( G.KeyValuePair<string,Schema> p in SchemaDict )
foreach( G.KeyValuePair<string,TableExpression> q in p.Value.TableDict )
q.Value.Commit( c );
}
/* Private methods */
void RollbackOrCommit()
{
if ( Rollback )
{
Log.Reset();
foreach( G.KeyValuePair<string,Schema> p in SchemaDict )
foreach( G.KeyValuePair<string,TableExpression> q in p.Value.TableDict )
q.Value.Rollback();
Rollback = false;
}
else
{
// Save indexes to underlying buffered streams ( can add more Log entries ).
SysStringIndex.PrepareToCommit();
SysBinaryIndex.PrepareToCommit();
foreach( G.KeyValuePair<string,Schema> p in SchemaDict )
foreach( G.KeyValuePair<string,TableExpression> q in p.Value.TableDict )
q.Value.PrepareToCommit();
if ( Log.Commit() )
{
SysString.Flush(); SysStringIndex.Commit();
SysBinary.Flush(); SysBinaryIndex.Commit();
foreach( G.KeyValuePair<string,Schema> p in SchemaDict )
foreach( G.KeyValuePair<string,TableExpression> q in p.Value.TableDict )
q.Value.Commit();
foreach ( long fileId in DeletedFiles )
{
var f = new IO.FileInfo( Name + fileId );
f.Delete();
}
Log.Reset();
}
}
DeletedFiles.Clear();
}
