/// <summary>
/// Loads the specified DFA automaton
/// </summary>
/// <param name="automaton">An automaton</param>
private void LoadDFA(Automaton automaton)
{
dfa = new Automata.DFA();
for (int i = 0; i != automaton.StatesCount; i++)
{
dfa.CreateState();
}
for (int i = 0; i != automaton.StatesCount; i++)
{
Automata.DFAState current = dfa.States[i];
AutomatonState stateData = automaton.GetState(i);
// retrieve the matched terminals
for (int j = 0; j != stateData.TerminalsCount; j++)
{
MatchedTerminal mt = stateData.GetTerminal(j);
Terminal terminal = terminals[mt.Index];
current.AddItem(terminal);
if (mt.Context != 0)
{
terminals[mt.Index].Context = mt.Context;
}
}
// retrieve the transitions
for (int j = 0; j != 256; j++)
{
int next = stateData.GetCachedTransition(j);
char c = Convert.ToChar(j);
if (next != Automaton.DEAD_STATE)
{
current.AddTransition(new CharSpan(c, c), dfa.States[next]);
}
}
for (int j = 0; j != stateData.BulkTransitionsCount; j++)
{
AutomatonTransition transition = stateData.GetBulkTransition(j);
current.AddTransition(new CharSpan(Convert.ToChar(transition.Start), Convert.ToChar(transition.End)), dfa.States[transition.Target]);
}
current.RepackTransitions();
}
}
/// <summary>
/// Generates the given state binary data
/// </summary>
/// <param name="writer">The output writer</param>
/// <param name="state">The state to export</param>
private void GenerateDataFor(BinaryWriter writer, Automata.DFAState state)
{
// build the transition data
ushort[] cache = new ushort[256];
for (int i = 0; i != 256; i++)
{
cache[i] = Automaton.DEAD_STATE;
}
ushort cached = 0; // the number of cached transitions
ushort slow = 0; // the number of non-cached transitions
foreach (CharSpan span in state.Transitions)
{
if (span.Begin <= 255)
{
cached++;
int end = span.End;
if (end >= 256)
{
end = 255;
slow++;
}
for (int i = span.Begin; i <= end; i++)
{
cache[i] = (ushort)state.GetChildBy(span).ID;
}
}
else
{
slow++;
}
}
// build the matched terminals data
List <ushort> contextIDs = new List <ushort>();
List <ushort> matched = new List <ushort>();
foreach (Automata.FinalItem item in state.Items)
{
Grammars.Terminal terminal = item as Grammars.Terminal;
if (!contextIDs.Contains((ushort)terminal.Context))
{
// this is the first time this context is found in the current DFA state
// this is the terminal with the most priority for this context
contextIDs.Add((ushort)terminal.Context);
matched.Add((ushort)terminals.IndexOf(terminal));
}
}
// write the number of matched terminals
writer.Write((ushort)matched.Count);
// write the total numer of transitions
writer.Write((ushort)(slow + cached));
// write the number of non-cached transitions
writer.Write(slow);
// write the matched terminals
for (int i = 0; i != matched.Count; i++)
{
writer.Write(contextIDs[i]);
writer.Write(matched[i]);
}
// write the cached transitions
for (int i = 0; i != 256; i++)
{
writer.Write(cache[i]);
}
// write the non-cached transitions
List <CharSpan> keys = new List <CharSpan>(state.Transitions);
keys.Sort(new System.Comparison <CharSpan>(CharSpan.CompareReverse));
foreach (CharSpan span in keys)
{
if (span.End <= 255)
{
break; // the rest of the transitions are in the cache
}
ushort begin = span.Begin;
if (begin <= 255)
{
begin = 256;
}
writer.Write(begin);
writer.Write(Convert.ToUInt16(span.End));
writer.Write((ushort)state.GetChildBy(span).ID);
}
}
