/// Get tree node at current input pointer + i ahead where i=1 is next node.
/// i<0 indicates nodes in the past. So -1 is previous node and -2 is
/// two nodes ago. LT(0) is undefined. For i>=n, return null.
/// Return null for LT(0) and any index that results in an absolute address
/// that is negative.
///
/// This is analogous to the _LT() method of the TokenStream, but this
/// returns a tree node instead of a token. Makes code gen identical
/// for both parser and tree grammars. :)
///
static pANTLR3_BASE_TREE
_LT (pANTLR3_TREE_NODE_STREAM tns, ANTLR3_INT32 k)
{
if (tns->ctns->p == -1)
{
fillBufferRoot(tns->ctns);
}
if (k < 0)
{
return LB(tns, -k);
}
else if (k == 0)
{
return &(tns->ctns->INVALID_NODE.baseTree);
}
// k was a legitimate request,
//
if (( tns->ctns->p + k - 1) >= (ANTLR3_INT32)(tns->ctns->nodes->count))
{
return &(tns->ctns->EOF_NODE.baseTree);
}
return tns->ctns->nodes->get(tns->ctns->nodes, tns->ctns->p + k - 1);
}
static pANTLR3_BASE_TREE
get (pANTLR3_TREE_NODE_STREAM tns, ANTLR3_INT32 k)
{
if (tns->ctns->p == -1)
{
fillBufferRoot(tns->ctns);
}
return tns->ctns->nodes->get(tns->ctns->nodes, k);
}
/// Consume the next node from the input stream
///
static void
consume (pANTLR3_INT_STREAM is)
{
pANTLR3_TREE_NODE_STREAM tns;
pANTLR3_COMMON_TREE_NODE_STREAM ctns;
tns = (pANTLR3_TREE_NODE_STREAM)(is->super);
ctns = tns->ctns;
if (ctns->p == -1)
{
fillBufferRoot(ctns);
}
ctns->p++;
}
/// Expensive to compute the size of the whole tree while parsing.
/// This method only returns how much input has been seen so far. So
/// after parsing it returns true size.
///
static ANTLR3_UINT32
size (pANTLR3_INT_STREAM is)
{
pANTLR3_TREE_NODE_STREAM tns;
pANTLR3_COMMON_TREE_NODE_STREAM ctns;
tns = (pANTLR3_TREE_NODE_STREAM)(is->super);
ctns = tns->ctns;
if (ctns->p == -1)
{
fillBufferRoot(ctns);
}
return ctns->nodes->size(ctns->nodes);
}
/// Mark the state of the input stream so that we can come back to it
/// after a syntactic predicate and so on.
///
static ANTLR3_MARKER
mark (pANTLR3_INT_STREAM is)
{
pANTLR3_TREE_NODE_STREAM tns;
pANTLR3_COMMON_TREE_NODE_STREAM ctns;
tns = (pANTLR3_TREE_NODE_STREAM)(is->super);
ctns = tns->ctns;
if (tns->ctns->p == -1)
{
fillBufferRoot(tns->ctns);
}
// Return the current mark point
//
ctns->tnstream->istream->lastMarker = ctns->tnstream->istream->index(ctns->tnstream->istream);
return ctns->tnstream->istream->lastMarker;
}
/// Determine the stream index for a particular node.
/// NB: This uses internal knowledge of the Antlr3 Vector for the
/// sake of efficiency. Don't do this in application code.
/// This is just an internal debugging type interface so does not need to be improved.
///
static ANTLR3_INT32
getNodeIndex(pANTLR3_COMMON_TREE_NODE_STREAM ctns, pANTLR3_BASE_TREE t)
{
ANTLR3_UINT32 i;
ANTLR3_UINT32 j;
pANTLR3_VECTOR_ELEMENT elements;
if (ctns->p == -1)
{
fillBufferRoot(ctns);
}
j = ctns->nodes->count;
elements = ctns->nodes->elements;
for (i = 0; i < j; i++)
{
if (t == elements[i].element)
{
return i;
}
}
}
