| /* |
| ********************************************************************** |
| * Copyright (C) 2002 International Business Machines Corporation * |
| * and others. All rights reserved. * |
| ********************************************************************** |
| */ |
| |
| // |
| // File: rbbinode.cpp |
| // |
| // Implementation of class RBBINode, which represents a node in the |
| // tree generated when parsing the Rules Based Break Iterator rules. |
| // |
| // This "Class" is actually closer to a struct. |
| // Code using it is expected to directly access fields much of the time. |
| // |
| |
| #include "unicode/unistr.h" |
| #include "unicode/uniset.h" |
| #include "unicode/uchar.h" |
| #include "unicode/parsepos.h" |
| #include "uvector.h" |
| |
| #include "rbbirb.h" |
| #include "rbbinode.h" |
| |
| #include "uassert.h" |
| |
| |
| U_NAMESPACE_BEGIN |
| |
| const char RBBINode::fgClassID=0; |
| |
| int RBBINode::gLastSerial = 0; |
| |
| |
| |
| //------------------------------------------------------------------------- |
| // |
| // Constructor. Just set the fields to reasonable default values. |
| // |
| //------------------------------------------------------------------------- |
| RBBINode::RBBINode(NodeType t) : UObject() { |
| fSerialNum = ++gLastSerial; |
| fType = t; |
| fParent = NULL; |
| fLeftChild = NULL; |
| fRightChild = NULL; |
| fInputSet = NULL; |
| fFirstPos = 0; |
| fLastPos = 0; |
| fNullable = FALSE; |
| fLookAheadEnd = FALSE; |
| fVal = 0; |
| fPrecedence = precZero; |
| |
| UErrorCode status = U_ZERO_ERROR; |
| fFirstPosSet = new UVector(status); // TODO - get a real status from somewhere |
| fLastPosSet = new UVector(status); |
| fFollowPos = new UVector(status); |
| if (t==opCat) {fPrecedence = precOpCat;} |
| else if (t==opOr) {fPrecedence = precOpOr;} |
| else if (t==opStart) {fPrecedence = precStart;} |
| else if (t==opLParen) {fPrecedence = precLParen;} |
| |
| }; |
| |
| |
| RBBINode::RBBINode(const RBBINode &other) : UObject(other) { |
| fSerialNum = ++gLastSerial; |
| fType = other.fType; |
| fParent = NULL; |
| fLeftChild = NULL; |
| fRightChild = NULL; |
| fInputSet = other.fInputSet; |
| fPrecedence = other.fPrecedence; |
| fText = other.fText; |
| fFirstPos = other.fFirstPos; |
| fLastPos = other.fLastPos; |
| fNullable = other.fNullable; |
| fVal = other.fVal; |
| UErrorCode status = U_ZERO_ERROR; |
| fFirstPosSet = new UVector(status); // TODO - get a real status from somewhere |
| fLastPosSet = new UVector(status); |
| fFollowPos = new UVector(status); |
| }; |
| |
| |
| //------------------------------------------------------------------------- |
| // |
| // Destructor. Deletes both this node AND any child nodes, |
| // except in the case of variable reference nodes. For |
| // these, the l. child points back to the definition, which |
| // is common for all references to the variable, meaning |
| // it can't be deleted here. |
| // |
| //------------------------------------------------------------------------- |
| RBBINode::~RBBINode() { |
| // printf("deleting node %8x serial %4d\n", this, this->fSerialNum); |
| delete fInputSet; |
| fInputSet = NULL; |
| |
| switch (this->fType) { |
| case varRef: |
| case setRef: |
| // for these node types, multiple instances point to the same "children" |
| // Storage ownership of children handled elsewhere. Don't delete here. |
| break; |
| |
| case uset: |
| delete fLeftChild; |
| // For usets, don't delete the right child; it's used to form a linked list of usets. |
| break; |
| |
| default: |
| delete fLeftChild; |
| fLeftChild = NULL; |
| delete fRightChild; |
| fRightChild = NULL; |
| } |
| |
| |
| delete fFirstPosSet; |
| delete fLastPosSet; |
| delete fFollowPos; |
| |
| } |
| |
| |
| //------------------------------------------------------------------------- |
| // |
| // cloneTree Make a copy of the subtree rooted at this node. |
| // Discard any variable references encountered along the way, |
| // and replace with copies of the variable's definitions. |
| // Used to replicate the expression underneath variable |
| // references in preparation for generating the DFA tables. |
| // |
| //------------------------------------------------------------------------- |
| RBBINode *RBBINode::cloneTree() { |
| RBBINode *n; |
| |
| if (fType == RBBINode::varRef) { |
| // If the current node is a variable reference, skip over it |
| // and clone the definition of the variable instead. |
| n = fLeftChild->cloneTree(); |
| } else if (fType == RBBINode::uset) { |
| n = this; |
| } else { |
| n = new RBBINode(*this); |
| if (fLeftChild != NULL) { |
| n->fLeftChild = fLeftChild->cloneTree(); |
| n->fLeftChild->fParent = n; |
| } |
| if (fRightChild != NULL) { |
| n->fRightChild = fRightChild->cloneTree(); |
| n->fRightChild->fParent = n; |
| } |
| } |
| return n; |
| }; |
| |
| |
| |
| //------------------------------------------------------------------------- |
| // |
| // flattenVariables Walk a parse tree, replacing any variable |
| // references with a copy of the variable's definition. |
| // Aside from variables, the tree is not changed. |
| // |
| // This function works by recursively walking the tree |
| // without doing anything until a variable reference is |
| // found, then calling cloneTree() at that point. Any |
| // nested references are handled by cloneTree(), not here. |
| // |
| //------------------------------------------------------------------------- |
| void RBBINode::flattenVariables() { |
| U_ASSERT(fType != varRef); |
| |
| if (fLeftChild != NULL) { |
| if (fLeftChild->fType==varRef) { |
| RBBINode *oldChild = fLeftChild; |
| fLeftChild = oldChild->cloneTree(); |
| fLeftChild->fParent = this; |
| delete oldChild; |
| } else { |
| fLeftChild->flattenVariables(); |
| } |
| } |
| |
| if (fRightChild != NULL) { |
| if (fRightChild->fType==varRef) { |
| RBBINode *oldChild = fRightChild; |
| fRightChild = oldChild->cloneTree(); |
| fRightChild->fParent = this; |
| delete oldChild; |
| } else { |
| fRightChild->flattenVariables(); |
| } |
| } |
| } |
| |
| |
| |
| //------------------------------------------------------------------------- |
| // |
| // flattenSets Walk the parse tree, replacing any nodes of type setRef |
| // with a copy of the expression tree for the set. A set's |
| // equivalent expression tree is precomputed and saved as |
| // the left child of the uset node. |
| // |
| //------------------------------------------------------------------------- |
| void RBBINode::flattenSets() { |
| U_ASSERT(fType != setRef); |
| |
| if (fLeftChild != NULL) { |
| if (fLeftChild->fType==setRef) { |
| RBBINode *setRefNode = fLeftChild; |
| RBBINode *usetNode = setRefNode->fLeftChild; |
| RBBINode *replTree = usetNode->fLeftChild; |
| fLeftChild = replTree->cloneTree(); |
| fLeftChild->fParent = this; |
| delete setRefNode; |
| } else { |
| fLeftChild->flattenSets(); |
| } |
| } |
| |
| if (fRightChild != NULL) { |
| if (fRightChild->fType==setRef) { |
| RBBINode *setRefNode = fRightChild; |
| RBBINode *usetNode = setRefNode->fLeftChild; |
| RBBINode *replTree = usetNode->fLeftChild; |
| fRightChild = replTree->cloneTree(); |
| fRightChild->fParent = this; |
| delete setRefNode; |
| } else { |
| fRightChild->flattenSets(); |
| } |
| } |
| } |
| |
| |
| |
| //------------------------------------------------------------------------- |
| // |
| // findNodes() Locate all the nodes of the specified type, starting |
| // at the specified root. |
| // |
| //------------------------------------------------------------------------- |
| void RBBINode::findNodes(UVector *dest, RBBINode::NodeType kind, UErrorCode &status) { |
| /* test for buffer overflows */ |
| if (U_FAILURE(status)) { |
| return; |
| } |
| if (fType == kind) { |
| dest->addElement(this, status); |
| } |
| if (fLeftChild != NULL) { |
| fLeftChild->findNodes(dest, kind, status); |
| } |
| if (fRightChild !=NULL && fType != RBBINode::uset) { |
| fRightChild->findNodes(dest, kind, status); |
| } |
| } |
| |
| |
| //------------------------------------------------------------------------- |
| // |
| // print. Print out a single node, for debugging. |
| // |
| //------------------------------------------------------------------------- |
| static const char *nodeTypeNames[] = { |
| "setRef", |
| "uset", |
| "varRef", |
| "leafChar", |
| "lookAhead", |
| "tag", |
| "endMark", |
| "opStart", |
| "opCat", |
| "opOr", |
| "opStar", |
| "opPlus", |
| "opQuestion", |
| "opBreak", |
| "opReverse", |
| "opLParen" |
| }; |
| |
| void RBBINode::print() { |
| RBBIDebugPrintf("%10p %12s %10p %10p %10p %4d %6d %d ", |
| (void *)this, nodeTypeNames[fType], (void *)fParent, (void *)fLeftChild, (void *)fRightChild, |
| fSerialNum, fFirstPos, fVal); |
| if (fType == varRef) { |
| printUnicodeString(fText); |
| } |
| RBBIDebugPrintf("\n"); |
| } |
| |
| |
| void RBBINode::printUnicodeString(const UnicodeString &s, int minWidth) |
| { |
| int i; |
| for (i=0; i<s.length(); i++) { |
| RBBIDebugPrintf("%c", s.charAt(i)); |
| // putc(s.charAt(i), stdout); |
| } |
| for (i=s.length(); i<minWidth; i++) { |
| RBBIDebugPrintf(" "); |
| } |
| } |
| |
| |
| //------------------------------------------------------------------------- |
| // |
| // print. Print out the tree of nodes rooted at "this" |
| // |
| //------------------------------------------------------------------------- |
| void RBBINode::printTree(UBool printHeading, UBool doVars) { |
| if (printHeading) { |
| RBBIDebugPrintf( "-------------------------------------------------------------------\n" |
| " Address type Parent LeftChild RightChild serial position value\n" |
| ); |
| } |
| this->print(); |
| // Only dump the definition under a variable reference if asked to. |
| // Unconditinally dump children of all other node types. |
| if (fType != varRef || doVars) { |
| if (fLeftChild != NULL) { |
| fLeftChild->printTree(FALSE); |
| } |
| |
| // Note: The right child field of uset nodes is borrowed to link them into a list |
| // They are actually a leaf node as far as the tree is concerned. |
| if (fRightChild != NULL && this->fType != RBBINode::uset) { |
| fRightChild->printTree(FALSE); |
| } |
| } |
| } |
| |
| |
| |
| U_NAMESPACE_END |
| |
| |