| |
| // |
| // file: rbbiscan.cpp |
| // |
| // Copyright (C) 2002-2010, International Business Machines Corporation and others. |
| // All Rights Reserved. |
| // |
| // This file contains the Rule Based Break Iterator Rule Builder functions for |
| // scanning the rules and assembling a parse tree. This is the first phase |
| // of compiling the rules. |
| // |
| // The overall of the rules is managed by class RBBIRuleBuilder, which will |
| // create and use an instance of this class as part of the process. |
| // |
| |
| #include "unicode/utypes.h" |
| |
| #if !UCONFIG_NO_BREAK_ITERATION |
| |
| #include "unicode/unistr.h" |
| #include "unicode/uniset.h" |
| #include "unicode/uchar.h" |
| #include "unicode/uchriter.h" |
| #include "unicode/parsepos.h" |
| #include "unicode/parseerr.h" |
| #include "util.h" |
| #include "cmemory.h" |
| #include "cstring.h" |
| |
| #include "rbbirpt.h" // Contains state table for the rbbi rules parser. |
| // generated by a Perl script. |
| #include "rbbirb.h" |
| #include "rbbinode.h" |
| #include "rbbiscan.h" |
| #include "rbbitblb.h" |
| |
| #include "uassert.h" |
| |
| |
| //------------------------------------------------------------------------------ |
| // |
| // Unicode Set init strings for each of the character classes needed for parsing a rule file. |
| // (Initialized with hex values for portability to EBCDIC based machines. |
| // Really ugly, but there's no good way to avoid it.) |
| // |
| // The sets are referred to by name in the rbbirpt.txt, which is the |
| // source form of the state transition table for the RBBI rule parser. |
| // |
| //------------------------------------------------------------------------------ |
| static const UChar gRuleSet_rule_char_pattern[] = { |
| // [ ^ [ \ p { Z } \ u 0 0 2 0 |
| 0x5b, 0x5e, 0x5b, 0x5c, 0x70, 0x7b, 0x5a, 0x7d, 0x5c, 0x75, 0x30, 0x30, 0x32, 0x30, |
| // - \ u 0 0 7 f ] - [ \ p |
| 0x2d, 0x5c, 0x75, 0x30, 0x30, 0x37, 0x66, 0x5d, 0x2d, 0x5b, 0x5c, 0x70, |
| // { L } ] - [ \ p { N } ] ] |
| 0x7b, 0x4c, 0x7d, 0x5d, 0x2d, 0x5b, 0x5c, 0x70, 0x7b, 0x4e, 0x7d, 0x5d, 0x5d, 0}; |
| |
| static const UChar gRuleSet_name_char_pattern[] = { |
| // [ _ \ p { L } \ p { N } ] |
| 0x5b, 0x5f, 0x5c, 0x70, 0x7b, 0x4c, 0x7d, 0x5c, 0x70, 0x7b, 0x4e, 0x7d, 0x5d, 0}; |
| |
| static const UChar gRuleSet_digit_char_pattern[] = { |
| // [ 0 - 9 ] |
| 0x5b, 0x30, 0x2d, 0x39, 0x5d, 0}; |
| |
| static const UChar gRuleSet_name_start_char_pattern[] = { |
| // [ _ \ p { L } ] |
| 0x5b, 0x5f, 0x5c, 0x70, 0x7b, 0x4c, 0x7d, 0x5d, 0 }; |
| |
| static const UChar kAny[] = {0x61, 0x6e, 0x79, 0x00}; // "any" |
| |
| |
| U_CDECL_BEGIN |
| static void U_CALLCONV RBBISetTable_deleter(void *p) { |
| U_NAMESPACE_QUALIFIER RBBISetTableEl *px = (U_NAMESPACE_QUALIFIER RBBISetTableEl *)p; |
| delete px->key; |
| // Note: px->val is owned by the linked list "fSetsListHead" in scanner. |
| // Don't delete the value nodes here. |
| uprv_free(px); |
| } |
| U_CDECL_END |
| |
| U_NAMESPACE_BEGIN |
| |
| //------------------------------------------------------------------------------ |
| // |
| // Constructor. |
| // |
| //------------------------------------------------------------------------------ |
| RBBIRuleScanner::RBBIRuleScanner(RBBIRuleBuilder *rb) |
| { |
| fRB = rb; |
| fStackPtr = 0; |
| fStack[fStackPtr] = 0; |
| fNodeStackPtr = 0; |
| fRuleNum = 0; |
| fNodeStack[0] = NULL; |
| |
| fSymbolTable = NULL; |
| fSetTable = NULL; |
| |
| fScanIndex = 0; |
| fNextIndex = 0; |
| |
| fReverseRule = FALSE; |
| fLookAheadRule = FALSE; |
| |
| fLineNum = 1; |
| fCharNum = 0; |
| fQuoteMode = FALSE; |
| |
| // Do not check status until after all critical fields are sufficiently initialized |
| // that the destructor can run cleanly. |
| if (U_FAILURE(*rb->fStatus)) { |
| return; |
| } |
| |
| // |
| // Set up the constant Unicode Sets. |
| // Note: These could be made static, lazily initialized, and shared among |
| // all instances of RBBIRuleScanners. BUT this is quite a bit simpler, |
| // and the time to build these few sets should be small compared to a |
| // full break iterator build. |
| fRuleSets[kRuleSet_rule_char-128] = UnicodeSet(gRuleSet_rule_char_pattern, *rb->fStatus); |
| UnicodeSet *whitespaceSet = uprv_openRuleWhiteSpaceSet(rb->fStatus); |
| if (U_FAILURE(*rb->fStatus)) { |
| return; |
| } |
| fRuleSets[kRuleSet_white_space-128] = *whitespaceSet; |
| delete whitespaceSet; |
| fRuleSets[kRuleSet_name_char-128] = UnicodeSet(gRuleSet_name_char_pattern, *rb->fStatus); |
| fRuleSets[kRuleSet_name_start_char-128] = UnicodeSet(gRuleSet_name_start_char_pattern, *rb->fStatus); |
| fRuleSets[kRuleSet_digit_char-128] = UnicodeSet(gRuleSet_digit_char_pattern, *rb->fStatus); |
| if (*rb->fStatus == U_ILLEGAL_ARGUMENT_ERROR) { |
| // This case happens if ICU's data is missing. UnicodeSet tries to look up property |
| // names from the init string, can't find them, and claims an illegal arguement. |
| // Change the error so that the actual problem will be clearer to users. |
| *rb->fStatus = U_BRK_INIT_ERROR; |
| } |
| if (U_FAILURE(*rb->fStatus)) { |
| return; |
| } |
| |
| fSymbolTable = new RBBISymbolTable(this, rb->fRules, *rb->fStatus); |
| if (fSymbolTable == NULL) { |
| *rb->fStatus = U_MEMORY_ALLOCATION_ERROR; |
| return; |
| } |
| fSetTable = uhash_open(uhash_hashUnicodeString, uhash_compareUnicodeString, NULL, rb->fStatus); |
| if (U_FAILURE(*rb->fStatus)) { |
| return; |
| } |
| uhash_setValueDeleter(fSetTable, RBBISetTable_deleter); |
| } |
| |
| |
| |
| //------------------------------------------------------------------------------ |
| // |
| // Destructor |
| // |
| //------------------------------------------------------------------------------ |
| RBBIRuleScanner::~RBBIRuleScanner() { |
| delete fSymbolTable; |
| if (fSetTable != NULL) { |
| uhash_close(fSetTable); |
| fSetTable = NULL; |
| |
| } |
| |
| |
| // Node Stack. |
| // Normally has one entry, which is the entire parse tree for the rules. |
| // If errors occured, there may be additional subtrees left on the stack. |
| while (fNodeStackPtr > 0) { |
| delete fNodeStack[fNodeStackPtr]; |
| fNodeStackPtr--; |
| } |
| |
| } |
| |
| //------------------------------------------------------------------------------ |
| // |
| // doParseAction Do some action during rule parsing. |
| // Called by the parse state machine. |
| // Actions build the parse tree and Unicode Sets, |
| // and maintain the parse stack for nested expressions. |
| // |
| // TODO: unify EParseAction and RBBI_RuleParseAction enum types. |
| // They represent exactly the same thing. They're separate |
| // only to work around enum forward declaration restrictions |
| // in some compilers, while at the same time avoiding multiple |
| // definitions problems. I'm sure that there's a better way. |
| // |
| //------------------------------------------------------------------------------ |
| UBool RBBIRuleScanner::doParseActions(int32_t action) |
| { |
| RBBINode *n = NULL; |
| |
| UBool returnVal = TRUE; |
| |
| switch (action) { |
| |
| case doExprStart: |
| pushNewNode(RBBINode::opStart); |
| fRuleNum++; |
| break; |
| |
| |
| case doExprOrOperator: |
| { |
| fixOpStack(RBBINode::precOpCat); |
| RBBINode *operandNode = fNodeStack[fNodeStackPtr--]; |
| RBBINode *orNode = pushNewNode(RBBINode::opOr); |
| orNode->fLeftChild = operandNode; |
| operandNode->fParent = orNode; |
| } |
| break; |
| |
| case doExprCatOperator: |
| // concatenation operator. |
| // For the implicit concatenation of adjacent terms in an expression that are |
| // not separated by any other operator. Action is invoked between the |
| // actions for the two terms. |
| { |
| fixOpStack(RBBINode::precOpCat); |
| RBBINode *operandNode = fNodeStack[fNodeStackPtr--]; |
| RBBINode *catNode = pushNewNode(RBBINode::opCat); |
| catNode->fLeftChild = operandNode; |
| operandNode->fParent = catNode; |
| } |
| break; |
| |
| case doLParen: |
| // Open Paren. |
| // The openParen node is a dummy operation type with a low precedence, |
| // which has the affect of ensuring that any real binary op that |
| // follows within the parens binds more tightly to the operands than |
| // stuff outside of the parens. |
| pushNewNode(RBBINode::opLParen); |
| break; |
| |
| case doExprRParen: |
| fixOpStack(RBBINode::precLParen); |
| break; |
| |
| case doNOP: |
| break; |
| |
| case doStartAssign: |
| // We've just scanned "$variable = " |
| // The top of the node stack has the $variable ref node. |
| |
| // Save the start position of the RHS text in the StartExpression node |
| // that precedes the $variableReference node on the stack. |
| // This will eventually be used when saving the full $variable replacement |
| // text as a string. |
| n = fNodeStack[fNodeStackPtr-1]; |
| n->fFirstPos = fNextIndex; // move past the '=' |
| |
| // Push a new start-of-expression node; needed to keep parse of the |
| // RHS expression happy. |
| pushNewNode(RBBINode::opStart); |
| break; |
| |
| |
| |
| |
| case doEndAssign: |
| { |
| // We have reached the end of an assignement statement. |
| // Current scan char is the ';' that terminates the assignment. |
| |
| // Terminate expression, leaves expression parse tree rooted in TOS node. |
| fixOpStack(RBBINode::precStart); |
| |
| RBBINode *startExprNode = fNodeStack[fNodeStackPtr-2]; |
| RBBINode *varRefNode = fNodeStack[fNodeStackPtr-1]; |
| RBBINode *RHSExprNode = fNodeStack[fNodeStackPtr]; |
| |
| // Save original text of right side of assignment, excluding the terminating ';' |
| // in the root of the node for the right-hand-side expression. |
| RHSExprNode->fFirstPos = startExprNode->fFirstPos; |
| RHSExprNode->fLastPos = fScanIndex; |
| fRB->fRules.extractBetween(RHSExprNode->fFirstPos, RHSExprNode->fLastPos, RHSExprNode->fText); |
| |
| // Expression parse tree becomes l. child of the $variable reference node. |
| varRefNode->fLeftChild = RHSExprNode; |
| RHSExprNode->fParent = varRefNode; |
| |
| // Make a symbol table entry for the $variableRef node. |
| fSymbolTable->addEntry(varRefNode->fText, varRefNode, *fRB->fStatus); |
| if (U_FAILURE(*fRB->fStatus)) { |
| // This is a round-about way to get the parse position set |
| // so that duplicate symbols error messages include a line number. |
| UErrorCode t = *fRB->fStatus; |
| *fRB->fStatus = U_ZERO_ERROR; |
| error(t); |
| } |
| |
| // Clean up the stack. |
| delete startExprNode; |
| fNodeStackPtr-=3; |
| break; |
| } |
| |
| case doEndOfRule: |
| { |
| fixOpStack(RBBINode::precStart); // Terminate expression, leaves expression |
| if (U_FAILURE(*fRB->fStatus)) { // parse tree rooted in TOS node. |
| break; |
| } |
| #ifdef RBBI_DEBUG |
| if (fRB->fDebugEnv && uprv_strstr(fRB->fDebugEnv, "rtree")) {printNodeStack("end of rule");} |
| #endif |
| U_ASSERT(fNodeStackPtr == 1); |
| |
| // If this rule includes a look-ahead '/', add a endMark node to the |
| // expression tree. |
| if (fLookAheadRule) { |
| RBBINode *thisRule = fNodeStack[fNodeStackPtr]; |
| RBBINode *endNode = pushNewNode(RBBINode::endMark); |
| RBBINode *catNode = pushNewNode(RBBINode::opCat); |
| fNodeStackPtr -= 2; |
| catNode->fLeftChild = thisRule; |
| catNode->fRightChild = endNode; |
| fNodeStack[fNodeStackPtr] = catNode; |
| endNode->fVal = fRuleNum; |
| endNode->fLookAheadEnd = TRUE; |
| } |
| |
| // All rule expressions are ORed together. |
| // The ';' that terminates an expression really just functions as a '|' with |
| // a low operator prededence. |
| // |
| // Each of the four sets of rules are collected separately. |
| // (forward, reverse, safe_forward, safe_reverse) |
| // OR this rule into the appropriate group of them. |
| // |
| RBBINode **destRules = (fReverseRule? &fRB->fReverseTree : fRB->fDefaultTree); |
| |
| if (*destRules != NULL) { |
| // This is not the first rule encounted. |
| // OR previous stuff (from *destRules) |
| // with the current rule expression (on the Node Stack) |
| // with the resulting OR expression going to *destRules |
| // |
| RBBINode *thisRule = fNodeStack[fNodeStackPtr]; |
| RBBINode *prevRules = *destRules; |
| RBBINode *orNode = pushNewNode(RBBINode::opOr); |
| orNode->fLeftChild = prevRules; |
| prevRules->fParent = orNode; |
| orNode->fRightChild = thisRule; |
| thisRule->fParent = orNode; |
| *destRules = orNode; |
| } |
| else |
| { |
| // This is the first rule encountered (for this direction). |
| // Just move its parse tree from the stack to *destRules. |
| *destRules = fNodeStack[fNodeStackPtr]; |
| } |
| fReverseRule = FALSE; // in preparation for the next rule. |
| fLookAheadRule = FALSE; |
| fNodeStackPtr = 0; |
| } |
| break; |
| |
| |
| case doRuleError: |
| error(U_BRK_RULE_SYNTAX); |
| returnVal = FALSE; |
| break; |
| |
| |
| case doVariableNameExpectedErr: |
| error(U_BRK_RULE_SYNTAX); |
| break; |
| |
| |
| // |
| // Unary operands + ? * |
| // These all appear after the operand to which they apply. |
| // When we hit one, the operand (may be a whole sub expression) |
| // will be on the top of the stack. |
| // Unary Operator becomes TOS, with the old TOS as its one child. |
| case doUnaryOpPlus: |
| { |
| RBBINode *operandNode = fNodeStack[fNodeStackPtr--]; |
| RBBINode *plusNode = pushNewNode(RBBINode::opPlus); |
| plusNode->fLeftChild = operandNode; |
| operandNode->fParent = plusNode; |
| } |
| break; |
| |
| case doUnaryOpQuestion: |
| { |
| RBBINode *operandNode = fNodeStack[fNodeStackPtr--]; |
| RBBINode *qNode = pushNewNode(RBBINode::opQuestion); |
| qNode->fLeftChild = operandNode; |
| operandNode->fParent = qNode; |
| } |
| break; |
| |
| case doUnaryOpStar: |
| { |
| RBBINode *operandNode = fNodeStack[fNodeStackPtr--]; |
| RBBINode *starNode = pushNewNode(RBBINode::opStar); |
| starNode->fLeftChild = operandNode; |
| operandNode->fParent = starNode; |
| } |
| break; |
| |
| case doRuleChar: |
| // A "Rule Character" is any single character that is a literal part |
| // of the regular expression. Like a, b and c in the expression "(abc*) | [:L:]" |
| // These are pretty uncommon in break rules; the terms are more commonly |
| // sets. To keep things uniform, treat these characters like as |
| // sets that just happen to contain only one character. |
| { |
| n = pushNewNode(RBBINode::setRef); |
| findSetFor(fC.fChar, n); |
| n->fFirstPos = fScanIndex; |
| n->fLastPos = fNextIndex; |
| fRB->fRules.extractBetween(n->fFirstPos, n->fLastPos, n->fText); |
| break; |
| } |
| |
| case doDotAny: |
| // scanned a ".", meaning match any single character. |
| { |
| n = pushNewNode(RBBINode::setRef); |
| findSetFor(kAny, n); |
| n->fFirstPos = fScanIndex; |
| n->fLastPos = fNextIndex; |
| fRB->fRules.extractBetween(n->fFirstPos, n->fLastPos, n->fText); |
| break; |
| } |
| |
| case doSlash: |
| // Scanned a '/', which identifies a look-ahead break position in a rule. |
| n = pushNewNode(RBBINode::lookAhead); |
| n->fVal = fRuleNum; |
| n->fFirstPos = fScanIndex; |
| n->fLastPos = fNextIndex; |
| fRB->fRules.extractBetween(n->fFirstPos, n->fLastPos, n->fText); |
| fLookAheadRule = TRUE; |
| break; |
| |
| |
| case doStartTagValue: |
| // Scanned a '{', the opening delimiter for a tag value within a rule. |
| n = pushNewNode(RBBINode::tag); |
| n->fVal = 0; |
| n->fFirstPos = fScanIndex; |
| n->fLastPos = fNextIndex; |
| break; |
| |
| case doTagDigit: |
| // Just scanned a decimal digit that's part of a tag value |
| { |
| n = fNodeStack[fNodeStackPtr]; |
| uint32_t v = u_charDigitValue(fC.fChar); |
| U_ASSERT(v < 10); |
| n->fVal = n->fVal*10 + v; |
| break; |
| } |
| |
| case doTagValue: |
| n = fNodeStack[fNodeStackPtr]; |
| n->fLastPos = fNextIndex; |
| fRB->fRules.extractBetween(n->fFirstPos, n->fLastPos, n->fText); |
| break; |
| |
| case doTagExpectedError: |
| error(U_BRK_MALFORMED_RULE_TAG); |
| returnVal = FALSE; |
| break; |
| |
| case doOptionStart: |
| // Scanning a !!option. At the start of string. |
| fOptionStart = fScanIndex; |
| break; |
| |
| case doOptionEnd: |
| { |
| UnicodeString opt(fRB->fRules, fOptionStart, fScanIndex-fOptionStart); |
| if (opt == UNICODE_STRING("chain", 5)) { |
| fRB->fChainRules = TRUE; |
| } else if (opt == UNICODE_STRING("LBCMNoChain", 11)) { |
| fRB->fLBCMNoChain = TRUE; |
| } else if (opt == UNICODE_STRING("forward", 7)) { |
| fRB->fDefaultTree = &fRB->fForwardTree; |
| } else if (opt == UNICODE_STRING("reverse", 7)) { |
| fRB->fDefaultTree = &fRB->fReverseTree; |
| } else if (opt == UNICODE_STRING("safe_forward", 12)) { |
| fRB->fDefaultTree = &fRB->fSafeFwdTree; |
| } else if (opt == UNICODE_STRING("safe_reverse", 12)) { |
| fRB->fDefaultTree = &fRB->fSafeRevTree; |
| } else if (opt == UNICODE_STRING("lookAheadHardBreak", 18)) { |
| fRB->fLookAheadHardBreak = TRUE; |
| } else { |
| error(U_BRK_UNRECOGNIZED_OPTION); |
| } |
| } |
| break; |
| |
| case doReverseDir: |
| fReverseRule = TRUE; |
| break; |
| |
| case doStartVariableName: |
| n = pushNewNode(RBBINode::varRef); |
| if (U_FAILURE(*fRB->fStatus)) { |
| break; |
| } |
| n->fFirstPos = fScanIndex; |
| break; |
| |
| case doEndVariableName: |
| n = fNodeStack[fNodeStackPtr]; |
| if (n==NULL || n->fType != RBBINode::varRef) { |
| error(U_BRK_INTERNAL_ERROR); |
| break; |
| } |
| n->fLastPos = fScanIndex; |
| fRB->fRules.extractBetween(n->fFirstPos+1, n->fLastPos, n->fText); |
| // Look the newly scanned name up in the symbol table |
| // If there's an entry, set the l. child of the var ref to the replacement expression. |
| // (We also pass through here when scanning assignments, but no harm is done, other |
| // than a slight wasted effort that seems hard to avoid. Lookup will be null) |
| n->fLeftChild = fSymbolTable->lookupNode(n->fText); |
| break; |
| |
| case doCheckVarDef: |
| n = fNodeStack[fNodeStackPtr]; |
| if (n->fLeftChild == NULL) { |
| error(U_BRK_UNDEFINED_VARIABLE); |
| returnVal = FALSE; |
| } |
| break; |
| |
| case doExprFinished: |
| break; |
| |
| case doRuleErrorAssignExpr: |
| error(U_BRK_ASSIGN_ERROR); |
| returnVal = FALSE; |
| break; |
| |
| case doExit: |
| returnVal = FALSE; |
| break; |
| |
| case doScanUnicodeSet: |
| scanSet(); |
| break; |
| |
| default: |
| error(U_BRK_INTERNAL_ERROR); |
| returnVal = FALSE; |
| break; |
| } |
| return returnVal; |
| } |
| |
| |
| |
| |
| //------------------------------------------------------------------------------ |
| // |
| // Error Report a rule parse error. |
| // Only report it if no previous error has been recorded. |
| // |
| //------------------------------------------------------------------------------ |
| void RBBIRuleScanner::error(UErrorCode e) { |
| if (U_SUCCESS(*fRB->fStatus)) { |
| *fRB->fStatus = e; |
| if (fRB->fParseError) { |
| fRB->fParseError->line = fLineNum; |
| fRB->fParseError->offset = fCharNum; |
| fRB->fParseError->preContext[0] = 0; |
| fRB->fParseError->preContext[0] = 0; |
| } |
| } |
| } |
| |
| |
| |
| |
| //------------------------------------------------------------------------------ |
| // |
| // fixOpStack The parse stack holds partially assembled chunks of the parse tree. |
| // An entry on the stack may be as small as a single setRef node, |
| // or as large as the parse tree |
| // for an entire expression (this will be the one item left on the stack |
| // when the parsing of an RBBI rule completes. |
| // |
| // This function is called when a binary operator is encountered. |
| // It looks back up the stack for operators that are not yet associated |
| // with a right operand, and if the precedence of the stacked operator >= |
| // the precedence of the current operator, binds the operand left, |
| // to the previously encountered operator. |
| // |
| //------------------------------------------------------------------------------ |
| void RBBIRuleScanner::fixOpStack(RBBINode::OpPrecedence p) { |
| RBBINode *n; |
| // printNodeStack("entering fixOpStack()"); |
| for (;;) { |
| n = fNodeStack[fNodeStackPtr-1]; // an operator node |
| if (n->fPrecedence == 0) { |
| RBBIDebugPuts("RBBIRuleScanner::fixOpStack, bad operator node"); |
| error(U_BRK_INTERNAL_ERROR); |
| return; |
| } |
| |
| if (n->fPrecedence < p || n->fPrecedence <= RBBINode::precLParen) { |
| // The most recent operand goes with the current operator, |
| // not with the previously stacked one. |
| break; |
| } |
| // Stack operator is a binary op ( '|' or concatenation) |
| // TOS operand becomes right child of this operator. |
| // Resulting subexpression becomes the TOS operand. |
| n->fRightChild = fNodeStack[fNodeStackPtr]; |
| fNodeStack[fNodeStackPtr]->fParent = n; |
| fNodeStackPtr--; |
| // printNodeStack("looping in fixOpStack() "); |
| } |
| |
| if (p <= RBBINode::precLParen) { |
| // Scan is at a right paren or end of expression. |
| // The scanned item must match the stack, or else there was an error. |
| // Discard the left paren (or start expr) node from the stack, |
| // leaving the completed (sub)expression as TOS. |
| if (n->fPrecedence != p) { |
| // Right paren encountered matched start of expression node, or |
| // end of expression matched with a left paren node. |
| error(U_BRK_MISMATCHED_PAREN); |
| } |
| fNodeStack[fNodeStackPtr-1] = fNodeStack[fNodeStackPtr]; |
| fNodeStackPtr--; |
| // Delete the now-discarded LParen or Start node. |
| delete n; |
| } |
| // printNodeStack("leaving fixOpStack()"); |
| } |
| |
| |
| |
| |
| //------------------------------------------------------------------------------ |
| // |
| // findSetFor given a UnicodeString, |
| // - find the corresponding Unicode Set (uset node) |
| // (create one if necessary) |
| // - Set fLeftChild of the caller's node (should be a setRef node) |
| // to the uset node |
| // Maintain a hash table of uset nodes, so the same one is always used |
| // for the same string. |
| // If a "to adopt" set is provided and we haven't seen this key before, |
| // add the provided set to the hash table. |
| // If the string is one (32 bit) char in length, the set contains |
| // just one element which is the char in question. |
| // If the string is "any", return a set containing all chars. |
| // |
| //------------------------------------------------------------------------------ |
| void RBBIRuleScanner::findSetFor(const UnicodeString &s, RBBINode *node, UnicodeSet *setToAdopt) { |
| |
| RBBISetTableEl *el; |
| |
| // First check whether we've already cached a set for this string. |
| // If so, just use the cached set in the new node. |
| // delete any set provided by the caller, since we own it. |
| el = (RBBISetTableEl *)uhash_get(fSetTable, &s); |
| if (el != NULL) { |
| delete setToAdopt; |
| node->fLeftChild = el->val; |
| U_ASSERT(node->fLeftChild->fType == RBBINode::uset); |
| return; |
| } |
| |
| // Haven't seen this set before. |
| // If the caller didn't provide us with a prebuilt set, |
| // create a new UnicodeSet now. |
| if (setToAdopt == NULL) { |
| if (s.compare(kAny, -1) == 0) { |
| setToAdopt = new UnicodeSet(0x000000, 0x10ffff); |
| } else { |
| UChar32 c; |
| c = s.char32At(0); |
| setToAdopt = new UnicodeSet(c, c); |
| } |
| } |
| |
| // |
| // Make a new uset node to refer to this UnicodeSet |
| // This new uset node becomes the child of the caller's setReference node. |
| // |
| RBBINode *usetNode = new RBBINode(RBBINode::uset); |
| if (usetNode == NULL) { |
| error(U_MEMORY_ALLOCATION_ERROR); |
| return; |
| } |
| usetNode->fInputSet = setToAdopt; |
| usetNode->fParent = node; |
| node->fLeftChild = usetNode; |
| usetNode->fText = s; |
| |
| |
| // |
| // Add the new uset node to the list of all uset nodes. |
| // |
| fRB->fUSetNodes->addElement(usetNode, *fRB->fStatus); |
| |
| |
| // |
| // Add the new set to the set hash table. |
| // |
| el = (RBBISetTableEl *)uprv_malloc(sizeof(RBBISetTableEl)); |
| UnicodeString *tkey = new UnicodeString(s); |
| if (tkey == NULL || el == NULL || setToAdopt == NULL) { |
| // Delete to avoid memory leak |
| delete tkey; |
| tkey = NULL; |
| uprv_free(el); |
| el = NULL; |
| delete setToAdopt; |
| setToAdopt = NULL; |
| |
| error(U_MEMORY_ALLOCATION_ERROR); |
| return; |
| } |
| el->key = tkey; |
| el->val = usetNode; |
| uhash_put(fSetTable, el->key, el, fRB->fStatus); |
| |
| return; |
| } |
| |
| |
| |
| // |
| // Assorted Unicode character constants. |
| // Numeric because there is no portable way to enter them as literals. |
| // (Think EBCDIC). |
| // |
| static const UChar chCR = 0x0d; // New lines, for terminating comments. |
| static const UChar chLF = 0x0a; |
| static const UChar chNEL = 0x85; // NEL newline variant |
| static const UChar chLS = 0x2028; // Unicode Line Separator |
| static const UChar chApos = 0x27; // single quote, for quoted chars. |
| static const UChar chPound = 0x23; // '#', introduces a comment. |
| static const UChar chBackSlash = 0x5c; // '\' introduces a char escape |
| static const UChar chLParen = 0x28; |
| static const UChar chRParen = 0x29; |
| |
| |
| //------------------------------------------------------------------------------ |
| // |
| // stripRules Return a rules string without unnecessary |
| // characters. |
| // |
| //------------------------------------------------------------------------------ |
| UnicodeString RBBIRuleScanner::stripRules(const UnicodeString &rules) { |
| UnicodeString strippedRules; |
| int rulesLength = rules.length(); |
| for (int idx = 0; idx < rulesLength; ) { |
| UChar ch = rules[idx++]; |
| if (ch == chPound) { |
| while (idx < rulesLength |
| && ch != chCR && ch != chLF && ch != chNEL) |
| { |
| ch = rules[idx++]; |
| } |
| } |
| if (!u_isISOControl(ch)) { |
| strippedRules.append(ch); |
| } |
| } |
| // strippedRules = strippedRules.unescape(); |
| return strippedRules; |
| } |
| |
| |
| //------------------------------------------------------------------------------ |
| // |
| // nextCharLL Low Level Next Char from rule input source. |
| // Get a char from the input character iterator, |
| // keep track of input position for error reporting. |
| // |
| //------------------------------------------------------------------------------ |
| UChar32 RBBIRuleScanner::nextCharLL() { |
| UChar32 ch; |
| |
| if (fNextIndex >= fRB->fRules.length()) { |
| return (UChar32)-1; |
| } |
| ch = fRB->fRules.char32At(fNextIndex); |
| fNextIndex = fRB->fRules.moveIndex32(fNextIndex, 1); |
| |
| if (ch == chCR || |
| ch == chNEL || |
| ch == chLS || |
| (ch == chLF && fLastChar != chCR)) { |
| // Character is starting a new line. Bump up the line number, and |
| // reset the column to 0. |
| fLineNum++; |
| fCharNum=0; |
| if (fQuoteMode) { |
| error(U_BRK_NEW_LINE_IN_QUOTED_STRING); |
| fQuoteMode = FALSE; |
| } |
| } |
| else { |
| // Character is not starting a new line. Except in the case of a |
| // LF following a CR, increment the column position. |
| if (ch != chLF) { |
| fCharNum++; |
| } |
| } |
| fLastChar = ch; |
| return ch; |
| } |
| |
| |
| //------------------------------------------------------------------------------ |
| // |
| // nextChar for rules scanning. At this level, we handle stripping |
| // out comments and processing backslash character escapes. |
| // The rest of the rules grammar is handled at the next level up. |
| // |
| //------------------------------------------------------------------------------ |
| void RBBIRuleScanner::nextChar(RBBIRuleChar &c) { |
| |
| // Unicode Character constants needed for the processing done by nextChar(), |
| // in hex because literals wont work on EBCDIC machines. |
| |
| fScanIndex = fNextIndex; |
| c.fChar = nextCharLL(); |
| c.fEscaped = FALSE; |
| |
| // |
| // check for '' sequence. |
| // These are recognized in all contexts, whether in quoted text or not. |
| // |
| if (c.fChar == chApos) { |
| if (fRB->fRules.char32At(fNextIndex) == chApos) { |
| c.fChar = nextCharLL(); // get nextChar officially so character counts |
| c.fEscaped = TRUE; // stay correct. |
| } |
| else |
| { |
| // Single quote, by itself. |
| // Toggle quoting mode. |
| // Return either '(' or ')', because quotes cause a grouping of the quoted text. |
| fQuoteMode = !fQuoteMode; |
| if (fQuoteMode == TRUE) { |
| c.fChar = chLParen; |
| } else { |
| c.fChar = chRParen; |
| } |
| c.fEscaped = FALSE; // The paren that we return is not escaped. |
| return; |
| } |
| } |
| |
| if (fQuoteMode) { |
| c.fEscaped = TRUE; |
| } |
| else |
| { |
| // We are not in a 'quoted region' of the source. |
| // |
| if (c.fChar == chPound) { |
| // Start of a comment. Consume the rest of it. |
| // The new-line char that terminates the comment is always returned. |
| // It will be treated as white-space, and serves to break up anything |
| // that might otherwise incorrectly clump together with a comment in |
| // the middle (a variable name, for example.) |
| for (;;) { |
| c.fChar = nextCharLL(); |
| if (c.fChar == (UChar32)-1 || // EOF |
| c.fChar == chCR || |
| c.fChar == chLF || |
| c.fChar == chNEL || |
| c.fChar == chLS) {break;} |
| } |
| } |
| if (c.fChar == (UChar32)-1) { |
| return; |
| } |
| |
| // |
| // check for backslash escaped characters. |
| // Use UnicodeString::unescapeAt() to handle them. |
| // |
| if (c.fChar == chBackSlash) { |
| c.fEscaped = TRUE; |
| int32_t startX = fNextIndex; |
| c.fChar = fRB->fRules.unescapeAt(fNextIndex); |
| if (fNextIndex == startX) { |
| error(U_BRK_HEX_DIGITS_EXPECTED); |
| } |
| fCharNum += fNextIndex-startX; |
| } |
| } |
| // putc(c.fChar, stdout); |
| } |
| |
| //------------------------------------------------------------------------------ |
| // |
| // Parse RBBI rules. The state machine for rules parsing is here. |
| // The state tables are hand-written in the file rbbirpt.txt, |
| // and converted to the form used here by a perl |
| // script rbbicst.pl |
| // |
| //------------------------------------------------------------------------------ |
| void RBBIRuleScanner::parse() { |
| uint16_t state; |
| const RBBIRuleTableEl *tableEl; |
| |
| if (U_FAILURE(*fRB->fStatus)) { |
| return; |
| } |
| |
| state = 1; |
| nextChar(fC); |
| // |
| // Main loop for the rule parsing state machine. |
| // Runs once per state transition. |
| // Each time through optionally performs, depending on the state table, |
| // - an advance to the the next input char |
| // - an action to be performed. |
| // - pushing or popping a state to/from the local state return stack. |
| // |
| for (;;) { |
| // Bail out if anything has gone wrong. |
| // RBBI rule file parsing stops on the first error encountered. |
| if (U_FAILURE(*fRB->fStatus)) { |
| break; |
| } |
| |
| // Quit if state == 0. This is the normal way to exit the state machine. |
| // |
| if (state == 0) { |
| break; |
| } |
| |
| // Find the state table element that matches the input char from the rule, or the |
| // class of the input character. Start with the first table row for this |
| // state, then linearly scan forward until we find a row that matches the |
| // character. The last row for each state always matches all characters, so |
| // the search will stop there, if not before. |
| // |
| tableEl = &gRuleParseStateTable[state]; |
| #ifdef RBBI_DEBUG |
| if (fRB->fDebugEnv && uprv_strstr(fRB->fDebugEnv, "scan")) { |
| RBBIDebugPrintf("char, line, col = (\'%c\', %d, %d) state=%s ", |
| fC.fChar, fLineNum, fCharNum, RBBIRuleStateNames[state]); |
| } |
| #endif |
| |
| for (;;) { |
| #ifdef RBBI_DEBUG |
| if (fRB->fDebugEnv && uprv_strstr(fRB->fDebugEnv, "scan")) { RBBIDebugPrintf(".");} |
| #endif |
| if (tableEl->fCharClass < 127 && fC.fEscaped == FALSE && tableEl->fCharClass == fC.fChar) { |
| // Table row specified an individual character, not a set, and |
| // the input character is not escaped, and |
| // the input character matched it. |
| break; |
| } |
| if (tableEl->fCharClass == 255) { |
| // Table row specified default, match anything character class. |
| break; |
| } |
| if (tableEl->fCharClass == 254 && fC.fEscaped) { |
| // Table row specified "escaped" and the char was escaped. |
| break; |
| } |
| if (tableEl->fCharClass == 253 && fC.fEscaped && |
| (fC.fChar == 0x50 || fC.fChar == 0x70 )) { |
| // Table row specified "escaped P" and the char is either 'p' or 'P'. |
| break; |
| } |
| if (tableEl->fCharClass == 252 && fC.fChar == (UChar32)-1) { |
| // Table row specified eof and we hit eof on the input. |
| break; |
| } |
| |
| if (tableEl->fCharClass >= 128 && tableEl->fCharClass < 240 && // Table specs a char class && |
| fC.fEscaped == FALSE && // char is not escaped && |
| fC.fChar != (UChar32)-1) { // char is not EOF |
| if (fRuleSets[tableEl->fCharClass-128].contains(fC.fChar)) { |
| // Table row specified a character class, or set of characters, |
| // and the current char matches it. |
| break; |
| } |
| } |
| |
| // No match on this row, advance to the next row for this state, |
| tableEl++; |
| } |
| if (fRB->fDebugEnv && uprv_strstr(fRB->fDebugEnv, "scan")) { RBBIDebugPuts("");} |
| |
| // |
| // We've found the row of the state table that matches the current input |
| // character from the rules string. |
| // Perform any action specified by this row in the state table. |
| if (doParseActions((int32_t)tableEl->fAction) == FALSE) { |
| // Break out of the state machine loop if the |
| // the action signalled some kind of error, or |
| // the action was to exit, occurs on normal end-of-rules-input. |
| break; |
| } |
| |
| if (tableEl->fPushState != 0) { |
| fStackPtr++; |
| if (fStackPtr >= kStackSize) { |
| error(U_BRK_INTERNAL_ERROR); |
| RBBIDebugPuts("RBBIRuleScanner::parse() - state stack overflow."); |
| fStackPtr--; |
| } |
| fStack[fStackPtr] = tableEl->fPushState; |
| } |
| |
| if (tableEl->fNextChar) { |
| nextChar(fC); |
| } |
| |
| // Get the next state from the table entry, or from the |
| // state stack if the next state was specified as "pop". |
| if (tableEl->fNextState != 255) { |
| state = tableEl->fNextState; |
| } else { |
| state = fStack[fStackPtr]; |
| fStackPtr--; |
| if (fStackPtr < 0) { |
| error(U_BRK_INTERNAL_ERROR); |
| RBBIDebugPuts("RBBIRuleScanner::parse() - state stack underflow."); |
| fStackPtr++; |
| } |
| } |
| |
| } |
| |
| // |
| // If there were NO user specified reverse rules, set up the equivalent of ".*;" |
| // |
| if (fRB->fReverseTree == NULL) { |
| fRB->fReverseTree = pushNewNode(RBBINode::opStar); |
| RBBINode *operand = pushNewNode(RBBINode::setRef); |
| findSetFor(kAny, operand); |
| fRB->fReverseTree->fLeftChild = operand; |
| operand->fParent = fRB->fReverseTree; |
| fNodeStackPtr -= 2; |
| } |
| |
| |
| // |
| // Parsing of the input RBBI rules is complete. |
| // We now have a parse tree for the rule expressions |
| // and a list of all UnicodeSets that are referenced. |
| // |
| #ifdef RBBI_DEBUG |
| if (fRB->fDebugEnv && uprv_strstr(fRB->fDebugEnv, "symbols")) {fSymbolTable->rbbiSymtablePrint();} |
| if (fRB->fDebugEnv && uprv_strstr(fRB->fDebugEnv, "ptree")) |
| { |
| RBBIDebugPrintf("Completed Forward Rules Parse Tree...\n"); |
| fRB->fForwardTree->printTree(TRUE); |
| RBBIDebugPrintf("\nCompleted Reverse Rules Parse Tree...\n"); |
| fRB->fReverseTree->printTree(TRUE); |
| RBBIDebugPrintf("\nCompleted Safe Point Forward Rules Parse Tree...\n"); |
| fRB->fSafeFwdTree->printTree(TRUE); |
| RBBIDebugPrintf("\nCompleted Safe Point Reverse Rules Parse Tree...\n"); |
| fRB->fSafeRevTree->printTree(TRUE); |
| } |
| #endif |
| } |
| |
| |
| //------------------------------------------------------------------------------ |
| // |
| // printNodeStack for debugging... |
| // |
| //------------------------------------------------------------------------------ |
| #ifdef RBBI_DEBUG |
| void RBBIRuleScanner::printNodeStack(const char *title) { |
| int i; |
| RBBIDebugPrintf("%s. Dumping node stack...\n", title); |
| for (i=fNodeStackPtr; i>0; i--) {fNodeStack[i]->printTree(TRUE);} |
| } |
| #endif |
| |
| |
| |
| |
| //------------------------------------------------------------------------------ |
| // |
| // pushNewNode create a new RBBINode of the specified type and push it |
| // onto the stack of nodes. |
| // |
| //------------------------------------------------------------------------------ |
| RBBINode *RBBIRuleScanner::pushNewNode(RBBINode::NodeType t) { |
| fNodeStackPtr++; |
| if (fNodeStackPtr >= kStackSize) { |
| error(U_BRK_INTERNAL_ERROR); |
| RBBIDebugPuts("RBBIRuleScanner::pushNewNode - stack overflow."); |
| *fRB->fStatus = U_BRK_INTERNAL_ERROR; |
| return NULL; |
| } |
| fNodeStack[fNodeStackPtr] = new RBBINode(t); |
| if (fNodeStack[fNodeStackPtr] == NULL) { |
| *fRB->fStatus = U_MEMORY_ALLOCATION_ERROR; |
| } |
| return fNodeStack[fNodeStackPtr]; |
| } |
| |
| |
| |
| //------------------------------------------------------------------------------ |
| // |
| // scanSet Construct a UnicodeSet from the text at the current scan |
| // position. Advance the scan position to the first character |
| // after the set. |
| // |
| // A new RBBI setref node referring to the set is pushed onto the node |
| // stack. |
| // |
| // The scan position is normally under the control of the state machine |
| // that controls rule parsing. UnicodeSets, however, are parsed by |
| // the UnicodeSet constructor, not by the RBBI rule parser. |
| // |
| //------------------------------------------------------------------------------ |
| void RBBIRuleScanner::scanSet() { |
| UnicodeSet *uset; |
| ParsePosition pos; |
| int startPos; |
| int i; |
| |
| if (U_FAILURE(*fRB->fStatus)) { |
| return; |
| } |
| |
| pos.setIndex(fScanIndex); |
| startPos = fScanIndex; |
| UErrorCode localStatus = U_ZERO_ERROR; |
| uset = new UnicodeSet(fRB->fRules, pos, USET_IGNORE_SPACE, |
| fSymbolTable, |
| localStatus); |
| if (uset == NULL) { |
| localStatus = U_MEMORY_ALLOCATION_ERROR; |
| } |
| if (U_FAILURE(localStatus)) { |
| // TODO: Get more accurate position of the error from UnicodeSet's return info. |
| // UnicodeSet appears to not be reporting correctly at this time. |
| #ifdef RBBI_DEBUG |
| RBBIDebugPrintf("UnicodeSet parse postion.ErrorIndex = %d\n", pos.getIndex()); |
| #endif |
| error(localStatus); |
| delete uset; |
| return; |
| } |
| |
| // Verify that the set contains at least one code point. |
| // |
| if (uset->isEmpty()) { |
| // This set is empty. |
| // Make it an error, because it almost certainly is not what the user wanted. |
| // Also, avoids having to think about corner cases in the tree manipulation code |
| // that occurs later on. |
| error(U_BRK_RULE_EMPTY_SET); |
| delete uset; |
| return; |
| } |
| |
| |
| // Advance the RBBI parse postion over the UnicodeSet pattern. |
| // Don't just set fScanIndex because the line/char positions maintained |
| // for error reporting would be thrown off. |
| i = pos.getIndex(); |
| for (;;) { |
| if (fNextIndex >= i) { |
| break; |
| } |
| nextCharLL(); |
| } |
| |
| if (U_SUCCESS(*fRB->fStatus)) { |
| RBBINode *n; |
| |
| n = pushNewNode(RBBINode::setRef); |
| n->fFirstPos = startPos; |
| n->fLastPos = fNextIndex; |
| fRB->fRules.extractBetween(n->fFirstPos, n->fLastPos, n->fText); |
| // findSetFor() serves several purposes here: |
| // - Adopts storage for the UnicodeSet, will be responsible for deleting. |
| // - Mantains collection of all sets in use, needed later for establishing |
| // character categories for run time engine. |
| // - Eliminates mulitiple instances of the same set. |
| // - Creates a new uset node if necessary (if this isn't a duplicate.) |
| findSetFor(n->fText, n, uset); |
| } |
| |
| } |
| |
| U_NAMESPACE_END |
| |
| #endif /* #if !UCONFIG_NO_BREAK_ITERATION */ |
