/***************************************************************
* Function: machine
* Description: Recursive descent regular expression parser.
**************************************************************/
private CNfa machine
(
)
{
CNfa start;
CNfa p;
SparseBitSet states;
if (CUtility.DESCENT_DEBUG)
{
CUtility.enter("machine", m_spec.m_lexeme, m_spec.m_current_token);
}
start = CAlloc.newCNfa(m_spec);
p = start;
states = m_lexGen.getStates();
/* Begin: Added for states. */
m_spec.m_current_token = CLexGen.EOS;
m_lexGen.advance();
/* End: Added for states. */
if (CLexGen.END_OF_INPUT != m_spec.m_current_token) // CSA fix.
{
p.m_next = rule();
processStates(states, p.m_next);
}
while (CLexGen.END_OF_INPUT != m_spec.m_current_token)
{
/* Make state changes HERE. */
states = m_lexGen.getStates();
/* Begin: Added for states. */
m_lexGen.advance();
if (CLexGen.END_OF_INPUT == m_spec.m_current_token)
{
break;
}
/* End: Added for states. */
p.m_next2 = CAlloc.newCNfa(m_spec);
p = p.m_next2;
p.m_next = rule();
processStates(states, p.m_next);
}
// CSA: add pseudo-rules for BOL and EOF
SparseBitSet all_states = new SparseBitSet();
for (int i = 0; i < m_spec.m_states.Count; ++i)
{
all_states.Set(i);
}
p.m_next2 = CAlloc.newCNfa(m_spec);
p = p.m_next2;
p.m_next = CAlloc.newCNfa(m_spec);
p.m_next.m_edge = CNfa.CCL;
p.m_next.m_next = CAlloc.newCNfa(m_spec);
p.m_next.m_set = new CSet();
p.m_next.m_set.add(m_spec.BOL);
p.m_next.m_set.add(m_spec.EOF);
p.m_next.m_next.m_accept = // do-nothing accept rule
new CAccept(new char[0], 0, m_input.m_line_number + 1);
processStates(all_states, p.m_next);
// CSA: done.
if (CUtility.DESCENT_DEBUG)
{
CUtility.leave("machine", m_spec.m_lexeme, m_spec.m_current_token);
}
return(start);
}