1035 lines
35 KiB
C++
1035 lines
35 KiB
C++
//
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// file: rbbi.c Contains the implementation of the rule based break iterator
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// runtime engine and the API implementation for
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// class RuleBasedBreakIterator
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//
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/*
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**********************************************************************
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* Copyright (C) 1999-2002 International Business Machines Corporation *
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* and others. All rights reserved. *
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**********************************************************************
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*/
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#include "unicode/utypes.h"
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#if !UCONFIG_NO_BREAK_ITERATION
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#include "unicode/rbbi.h"
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#include "unicode/schriter.h"
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#include "unicode/udata.h"
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#include "rbbidata.h"
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#include "rbbirb.h"
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#include "filestrm.h"
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#include "cmemory.h"
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#include "cstring.h"
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#include "uassert.h"
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U_NAMESPACE_BEGIN
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static const int16_t START_STATE = 1; // The state number of the starting state
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static const int16_t STOP_STATE = 0; // The state-transition value indicating "stop"
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/**
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* Class ID. (value is irrelevant; address is important)
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*/
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const char
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RuleBasedBreakIterator::fgClassID = 0;
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//=======================================================================
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// constructors
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//=======================================================================
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/**
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* Constructs a RuleBasedBreakIterator that uses the already-created
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* tables object that is passed in as a parameter.
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*/
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RuleBasedBreakIterator::RuleBasedBreakIterator(RBBIDataHeader* data, UErrorCode &status)
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{
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init();
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if (U_FAILURE(status)) {return;};
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fData = new RBBIDataWrapper(data, status);
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if(fData == 0) {
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status = U_MEMORY_ALLOCATION_ERROR;
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return;
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}
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}
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//-------------------------------------------------------------------------------
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//
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// Constructor from a UDataMemory handle to precompiled break rules
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// stored in an ICU data file.
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//
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//-------------------------------------------------------------------------------
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RuleBasedBreakIterator::RuleBasedBreakIterator(UDataMemory* udm, UErrorCode &status)
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{
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init();
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if (U_FAILURE(status)) {return;};
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fData = new RBBIDataWrapper(udm, status);
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if(fData == 0) {
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status = U_MEMORY_ALLOCATION_ERROR;
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return;
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}
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}
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//-------------------------------------------------------------------------------
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//
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// Constructor from a set of rules supplied as a string.
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//
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//-------------------------------------------------------------------------------
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RuleBasedBreakIterator::RuleBasedBreakIterator( const UnicodeString &rules,
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UParseError &parseError,
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UErrorCode &status)
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{
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init();
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if (U_FAILURE(status)) {return;};
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RuleBasedBreakIterator *bi = (RuleBasedBreakIterator *)
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RBBIRuleBuilder::createRuleBasedBreakIterator(rules, parseError, status);
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// Note: This is a bit awkward. The RBBI ruleBuilder has a factory method that
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// creates and returns a complete RBBI. From here, in a constructor, we
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// can't just return the object created by the builder factory, hence
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// the assignment of the factory created object to "this".
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if (U_SUCCESS(status)) {
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*this = *bi;
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delete bi;
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}
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}
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//-------------------------------------------------------------------------------
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//
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// Default Constructor. Create an empty shell that can be set up later.
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// Used when creating a RuleBasedBreakIterator from a set
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// of rules.
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//-------------------------------------------------------------------------------
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RuleBasedBreakIterator::RuleBasedBreakIterator() {
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init();
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}
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//-------------------------------------------------------------------------------
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//
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// Copy constructor. Will produce a break iterator with the same behavior,
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// and which iterates over the same text, as the one passed in.
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//
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//-------------------------------------------------------------------------------
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RuleBasedBreakIterator::RuleBasedBreakIterator(const RuleBasedBreakIterator& other)
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: BreakIterator(other)
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{
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this->init();
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*this = other;
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}
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/**
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* Destructor
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*/
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RuleBasedBreakIterator::~RuleBasedBreakIterator() {
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delete fText;
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fText = NULL;
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if (fData != NULL) {
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fData->removeReference();
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fData = NULL;
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}
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}
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/**
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* Assignment operator. Sets this iterator to have the same behavior,
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* and iterate over the same text, as the one passed in.
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*/
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RuleBasedBreakIterator&
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RuleBasedBreakIterator::operator=(const RuleBasedBreakIterator& that) {
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if (this == &that) {
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return *this;
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}
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delete fText;
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fText = NULL;
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if (that.fText != NULL) {
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fText = that.fText->clone();
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}
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if (fData != NULL) {
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fData->removeReference();
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fData = NULL;
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}
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if (that.fData != NULL) {
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fData = that.fData->addReference();
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}
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fTrace = that.fTrace;
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return *this;
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}
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//-----------------------------------------------------------------------------
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//
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// init() Shared initialization routine. Used by all the constructors.
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// Initializes all fields, leaving the object in a consistent state.
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//
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//-----------------------------------------------------------------------------
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UBool RuleBasedBreakIterator::fTrace = FALSE;
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void RuleBasedBreakIterator::init() {
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static UBool debugInitDone = FALSE;
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fText = NULL;
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fData = NULL;
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fCharMappings = NULL;
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fLastBreakTag = 0;
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fLastBreakTagValid = TRUE;
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fDictionaryCharCount = 0;
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if (debugInitDone == FALSE) {
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#ifdef RBBI_DEBUG
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char *debugEnv = getenv("U_RBBIDEBUG");
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if (debugEnv && uprv_strstr(debugEnv, "trace")) {
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fTrace = TRUE;
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}
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#endif
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debugInitDone = TRUE;
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}
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}
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//-----------------------------------------------------------------------------
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//
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// clone - Returns a newly-constructed RuleBasedBreakIterator with the same
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// behavior, and iterating over the same text, as this one.
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// Virtual function: does the right thing with subclasses.
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//
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//-----------------------------------------------------------------------------
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BreakIterator*
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RuleBasedBreakIterator::clone(void) const {
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return new RuleBasedBreakIterator(*this);
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}
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/**
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* Equality operator. Returns TRUE if both BreakIterators are of the
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* same class, have the same behavior, and iterate over the same text.
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*/
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UBool
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RuleBasedBreakIterator::operator==(const BreakIterator& that) const {
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UBool r = FALSE;
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if (that.getDynamicClassID() != getDynamicClassID()) {
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return r;
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}
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const RuleBasedBreakIterator& that2 = (const RuleBasedBreakIterator&) that;
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if (fText == that2.fText ||
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(fText != NULL && that2.fText != NULL && *that2.fText == *fText)) {
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if (that2.fData == fData ||
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(fData != NULL && that2.fData != NULL && *that2.fData == *fData)) {
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r = TRUE;
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}
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}
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return r;
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}
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/**
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* Compute a hash code for this BreakIterator
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* @return A hash code
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*/
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int32_t
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RuleBasedBreakIterator::hashCode(void) const {
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int32_t hash = 0;
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if (fData != NULL) {
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hash = fData->hashCode();
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}
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return hash;
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}
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/**
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* Returns the description used to create this iterator
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*/
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const UnicodeString&
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RuleBasedBreakIterator::getRules() const {
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if (fData != NULL) {
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return fData->getRuleSourceString();
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} else {
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static const UnicodeString *s;
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if (s == NULL) {
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// TODO: something more elegant here.
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// perhaps API should return the string by value.
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// Note: thread unsafe init & leak are semi-ok, better than
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// what was before. Sould be cleaned up, though.
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s = new UnicodeString;
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}
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return *s;
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}
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}
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//=======================================================================
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// BreakIterator overrides
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//=======================================================================
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/**
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* Return a CharacterIterator over the text being analyzed. This version
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* of this method returns the actual CharacterIterator we're using internally.
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* Changing the state of this iterator can have undefined consequences. If
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* you need to change it, clone it first.
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* @return An iterator over the text being analyzed.
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*/
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const CharacterIterator&
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RuleBasedBreakIterator::getText() const {
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RuleBasedBreakIterator* nonConstThis = (RuleBasedBreakIterator*)this;
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// The iterator is initialized pointing to no text at all, so if this
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// function is called while we're in that state, we have to fudge an
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// an iterator to return.
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if (nonConstThis->fText == NULL) {
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// TODO: do this in a way that does not do a default conversion!
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nonConstThis->fText = new StringCharacterIterator("");
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};
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return *nonConstThis->fText;
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}
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/**
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* Set the iterator to analyze a new piece of text. This function resets
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* the current iteration position to the beginning of the text.
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* @param newText An iterator over the text to analyze.
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*/
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void
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RuleBasedBreakIterator::adoptText(CharacterIterator* newText) {
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reset();
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delete fText;
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fText = newText;
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this->first();
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}
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/**
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* Set the iterator to analyze a new piece of text. This function resets
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* the current iteration position to the beginning of the text.
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* @param newText An iterator over the text to analyze.
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*/
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void
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RuleBasedBreakIterator::setText(const UnicodeString& newText) {
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reset();
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if (fText != NULL && fText->getDynamicClassID()
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== StringCharacterIterator::getStaticClassID()) {
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((StringCharacterIterator*)fText)->setText(newText);
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}
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else {
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delete fText;
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fText = new StringCharacterIterator(newText);
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}
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this->first();
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}
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/**
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* Sets the current iteration position to the beginning of the text.
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* (i.e., the CharacterIterator's starting offset).
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* @return The offset of the beginning of the text.
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*/
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int32_t RuleBasedBreakIterator::first(void) {
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reset();
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fLastBreakTag = 0;
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fLastBreakTagValid = TRUE;
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if (fText == NULL)
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return BreakIterator::DONE;
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fText->first();
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return fText->getIndex();
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}
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/**
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* Sets the current iteration position to the end of the text.
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* (i.e., the CharacterIterator's ending offset).
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* @return The text's past-the-end offset.
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*/
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int32_t RuleBasedBreakIterator::last(void) {
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reset();
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if (fText == NULL) {
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fLastBreakTag = 0;
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fLastBreakTagValid = TRUE;
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return BreakIterator::DONE;
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}
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// I'm not sure why, but t.last() returns the offset of the last character,
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// rather than the past-the-end offset
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//
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// (It's so a loop like for(p=it.last(); p!=DONE; p=it.previous()) ...
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// will work correctly.)
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fLastBreakTagValid = FALSE;
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int32_t pos = fText->endIndex();
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fText->setIndex(pos);
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return pos;
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}
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/**
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* Advances the iterator either forward or backward the specified number of steps.
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* Negative values move backward, and positive values move forward. This is
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* equivalent to repeatedly calling next() or previous().
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* @param n The number of steps to move. The sign indicates the direction
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* (negative is backwards, and positive is forwards).
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* @return The character offset of the boundary position n boundaries away from
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* the current one.
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*/
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int32_t RuleBasedBreakIterator::next(int32_t n) {
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int32_t result = current();
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while (n > 0) {
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result = handleNext();
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--n;
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}
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while (n < 0) {
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result = previous();
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++n;
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}
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return result;
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}
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/**
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* Advances the iterator to the next boundary position.
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* @return The position of the first boundary after this one.
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*/
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int32_t RuleBasedBreakIterator::next(void) {
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return handleNext();
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}
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/**
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* Advances the iterator backwards, to the last boundary preceding this one.
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* @return The position of the last boundary position preceding this one.
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*/
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int32_t RuleBasedBreakIterator::previous(void) {
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// if we're already sitting at the beginning of the text, return DONE
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if (fText == NULL || current() == fText->startIndex()) {
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fLastBreakTag = 0;
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fLastBreakTagValid = TRUE;
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return BreakIterator::DONE;
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}
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// set things up. handlePrevious() will back us up to some valid
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// break position before the current position (we back our internal
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// iterator up one step to prevent handlePrevious() from returning
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// the current position), but not necessarily the last one before
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// where we started
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int32_t start = current();
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fText->previous32();
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int32_t lastResult = handlePrevious();
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int32_t result = lastResult;
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int32_t lastTag = 0;
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UBool breakTagValid = FALSE;
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// iterate forward from the known break position until we pass our
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// starting point. The last break position before the starting
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// point is our return value
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for (;;) {
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result = handleNext();
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if (result == BreakIterator::DONE || result >= start) {
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break;
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}
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lastResult = result;
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lastTag = fLastBreakTag;
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breakTagValid = TRUE;
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}
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// fLastBreakTag wants to have the value for section of text preceding
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// the result position that we are to return (in lastResult.) If
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// the backwards rules overshot and the above loop had to do two or more
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// handleNext()s to move up to the desired return position, we will have a valid
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// tag value. But, if handlePrevious() took us to exactly the correct result positon,
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// we wont have a tag value for that position, which is only set by handleNext().
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// set the current iteration position to be the last break position
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// before where we started, and then return that value
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fText->setIndex(lastResult);
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fLastBreakTag = lastTag; // for use by getRuleStatus()
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fLastBreakTagValid = breakTagValid;
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return lastResult;
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}
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/**
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* Sets the iterator to refer to the first boundary position following
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* the specified position.
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* @offset The position from which to begin searching for a break position.
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* @return The position of the first break after the current position.
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*/
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int32_t RuleBasedBreakIterator::following(int32_t offset) {
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// if the offset passed in is already past the end of the text,
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// just return DONE; if it's before the beginning, return the
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// text's starting offset
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fLastBreakTag = 0;
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fLastBreakTagValid = TRUE;
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if (fText == NULL || offset >= fText->endIndex()) {
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// fText->setToEnd();
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// return BreakIterator::DONE;
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last();
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return next();
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}
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else if (offset < fText->startIndex()) {
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// fText->setToStart();
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// return fText->startIndex();
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return first();
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}
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// otherwise, set our internal iteration position (temporarily)
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// to the position passed in. If this is the _beginning_ position,
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// then we can just use next() to get our return value
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fText->setIndex(offset);
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if (offset == fText->startIndex())
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return handleNext();
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// otherwise, we have to sync up first. Use handlePrevious() to back
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// us up to a known break position before the specified position (if
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// we can determine that the specified position is a break position,
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// we don't back up at all). This may or may not be the last break
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// position at or before our starting position. Advance forward
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// from here until we've passed the starting position. The position
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// we stop on will be the first break position after the specified one.
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int32_t result = previous();
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while (result != BreakIterator::DONE && result <= offset) {
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result = next();
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}
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return result;
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}
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/**
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* Sets the iterator to refer to the last boundary position before the
|
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* specified position.
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* @offset The position to begin searching for a break from.
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* @return The position of the last boundary before the starting position.
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*/
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int32_t RuleBasedBreakIterator::preceding(int32_t offset) {
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// if the offset passed in is already past the end of the text,
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// just return DONE; if it's before the beginning, return the
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// text's starting offset
|
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if (fText == NULL || offset > fText->endIndex()) {
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// return BreakIterator::DONE;
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return last();
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}
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else if (offset < fText->startIndex()) {
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return first();
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}
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// if we start by updating the current iteration position to the
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// position specified by the caller, we can just use previous()
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// to carry out this operation
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fText->setIndex(offset);
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return previous();
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}
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|
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/**
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* Returns true if the specfied position is a boundary position. As a side
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* effect, leaves the iterator pointing to the first boundary position at
|
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* or after "offset".
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* @param offset the offset to check.
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* @return True if "offset" is a boundary position.
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*/
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UBool RuleBasedBreakIterator::isBoundary(int32_t offset) {
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// the beginning index of the iterator is always a boundary position by definition
|
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if (fText == NULL || offset == fText->startIndex()) {
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first(); // For side effects on current position, tag values.
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return TRUE;
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}
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// out-of-range indexes are never boundary positions
|
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if (offset < fText->startIndex()) {
|
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first(); // For side effects on current position, tag values.
|
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return FALSE;
|
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}
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|
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if (offset > fText->endIndex()) {
|
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last(); // For side effects on current position, tag values.
|
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return FALSE;
|
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}
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|
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// otherwise, we can use following() on the position before the specified
|
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// one and return true if the position we get back is the one the user
|
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// specified
|
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return following(offset - 1) == offset;
|
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}
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|
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/**
|
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* Returns the current iteration position.
|
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* @return The current iteration position.
|
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*/
|
|
int32_t RuleBasedBreakIterator::current(void) const {
|
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return (fText != NULL) ? fText->getIndex() : BreakIterator::DONE;
|
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}
|
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|
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//=======================================================================
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// implementation
|
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//=======================================================================
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//-----------------------------------------------------------------------------------
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|
//
|
|
// handleNext()
|
|
// This method is the actual implementation of the next() method. All iteration
|
|
// vectors through here. This method initializes the state machine to state 1
|
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// and advances through the text character by character until we reach the end
|
|
// of the text or the state machine transitions to state 0. We update our return
|
|
// value every time the state machine passes through a possible end state.
|
|
//
|
|
//-----------------------------------------------------------------------------------
|
|
int32_t RuleBasedBreakIterator::handleNext(void) {
|
|
if (fTrace) {
|
|
RBBIDebugPrintf("Handle Next pos char state category \n");
|
|
}
|
|
|
|
// No matter what, handleNext alway correctly sets the break tag value.
|
|
fLastBreakTagValid = TRUE;
|
|
|
|
// if we're already at the end of the text, return DONE.
|
|
if (fText == NULL || fData == NULL || fText->getIndex() == fText->endIndex()) {
|
|
fLastBreakTag = 0;
|
|
return BreakIterator::DONE;
|
|
}
|
|
|
|
// no matter what, we always advance at least one character forward
|
|
int32_t result = fText->getIndex() + 1;
|
|
int32_t lookaheadResult = 0;
|
|
|
|
// Initialize the state machine. Begin in state 1
|
|
int32_t state = START_STATE;
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int16_t category;
|
|
UChar32 c = fText->current32();
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RBBIStateTableRow *row;
|
|
int32_t lookaheadStatus = 0;
|
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int32_t lookaheadTag = 0;
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|
|
|
fLastBreakTag = 0;
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|
|
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row = (RBBIStateTableRow *) // Point to starting row of state table.
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(fData->fForwardTable->fTableData + (fData->fForwardTable->fRowLen * state));
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// Character Category fetch for starting character.
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// See comments on character category code within loop, below.
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|
UTRIE_GET16(&fData->fTrie, c, category);
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if ((category & 0x4000) != 0) {
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|
fDictionaryCharCount++;
|
|
category &= ~0x4000;
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|
}
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|
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// loop until we reach the end of the text or transition to state 0
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|
for (;;) {
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if (c == CharacterIterator::DONE && fText->hasNext()==FALSE) {
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// Note: CharacterIterator::DONE is 0xffff, which is also a legal
|
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// character value. Check for DONE first, because it's quicker,
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// but also need to check fText->hasNext() to be certain.
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break;
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}
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// look up the current character's character category, which tells us
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// which column in the state table to look at.
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// Note: the 16 in UTRIE_GET16 refers to the size of the data being returned,
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// not the size of the character going in.
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//
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UTRIE_GET16(&fData->fTrie, c, category);
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// Check the dictionary bit in the character's category.
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// Counter is only used by dictionary based iterators (subclasses).
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// Chars that need to be handled by a dictionary have a flag bit set
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// in their category values.
|
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//
|
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if ((category & 0x4000) != 0) {
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fDictionaryCharCount++;
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// And off the dictionary flag bit.
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category &= ~0x4000;
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|
}
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|
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if (fTrace) {
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RBBIDebugPrintf(" %4d ", fText->getIndex());
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if (0x20<=c && c<0x7f) {
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RBBIDebugPrintf("\"%c\" ", c);
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|
} else {
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RBBIDebugPrintf("%5x ", c);
|
|
}
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RBBIDebugPrintf("%3d %3d\n", state, category);
|
|
}
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// look up a state transition in the state table
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state = row->fNextState[category];
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row = (RBBIStateTableRow *)
|
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(fData->fForwardTable->fTableData + (fData->fForwardTable->fRowLen * state));
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|
|
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// Get the next character. Doing it here positions the iterator
|
|
// to the correct position for recording matches in the code that
|
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// follows.
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// TODO: 16 bit next, and a 16 bit TRIE lookup, with escape code
|
|
// for non-BMP chars, would be faster.
|
|
c = fText->next32();
|
|
|
|
if (row->fAccepting == 0 && row->fLookAhead == 0) {
|
|
// No match, nothing of interest happening, common case.
|
|
goto continueOn;
|
|
}
|
|
|
|
if (row->fAccepting == -1) {
|
|
// Match found, common case, no lookahead involved.
|
|
// (It's possible that some lookahead rule matched here also,
|
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// but since there's an unconditional match, we'll favor that.)
|
|
result = fText->getIndex();
|
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lookaheadStatus = 0; // clear out any pending look-ahead matches.
|
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fLastBreakTag = row->fTag; // Remember the break status (tag) value.
|
|
goto continueOn;
|
|
}
|
|
|
|
if (row->fAccepting == 0 && row->fLookAhead != 0) {
|
|
// Lookahead match point. Remember it, but only if no other rule has
|
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// unconitionally matched up to this point.
|
|
// TODO: handle case where there's a pending match from a different rule -
|
|
// where lookaheadStatus != 0 && lookaheadStatus != row->fLookAhead.
|
|
int32_t r = fText->getIndex();
|
|
if (r > result) {
|
|
lookaheadResult = r;
|
|
lookaheadStatus = row->fLookAhead;
|
|
lookaheadTag = row->fTag;
|
|
}
|
|
goto continueOn;
|
|
}
|
|
|
|
if (row->fAccepting != 0 && row->fLookAhead != 0) {
|
|
// Lookahead match is completed. Set the result accordingly, but only
|
|
// if no other rule has matched further in the mean time.
|
|
if (lookaheadResult > result) {
|
|
U_ASSERT(row->fAccepting == lookaheadStatus); // TODO: handle this case
|
|
// of overlapping lookahead matches.
|
|
result = lookaheadResult;
|
|
fLastBreakTag = lookaheadTag;
|
|
lookaheadStatus = 0;
|
|
}
|
|
goto continueOn;
|
|
}
|
|
|
|
continueOn:
|
|
if (state == STOP_STATE) {
|
|
break;
|
|
}
|
|
|
|
// c = fText->next32();
|
|
}
|
|
|
|
// if we've run off the end of the text, and the very last character took us into
|
|
// a lookahead state, advance the break position to the lookahead position
|
|
// (the theory here is that if there are no characters at all after the lookahead
|
|
// position, that always matches the lookahead criteria)
|
|
// TODO: is this really the right behavior?
|
|
if (c == CharacterIterator::DONE &&
|
|
fText->hasNext()==FALSE &&
|
|
lookaheadResult == fText->endIndex()) {
|
|
result = lookaheadResult;
|
|
fLastBreakTag = lookaheadTag;
|
|
}
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|
|
|
|
fText->setIndex(result);
|
|
if (fTrace) {
|
|
RBBIDebugPrintf("result = %d\n\n", result);
|
|
}
|
|
return result;
|
|
}
|
|
|
|
//-----------------------------------------------------------------------------------
|
|
//
|
|
// handlePrevious()
|
|
//
|
|
// This method backs the iterator back up to a "safe position" in the text.
|
|
// This is a position that we know, without any context, must be a break position.
|
|
// The various calling methods then iterate forward from this safe position to
|
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// the appropriate position to return.
|
|
//
|
|
// The logic of this function is very similar to handleNext(), above.
|
|
//
|
|
//-----------------------------------------------------------------------------------
|
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int32_t RuleBasedBreakIterator::handlePrevious(void) {
|
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if (fText == NULL || fData == NULL) {
|
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return 0;
|
|
}
|
|
if (fData->fReverseTable == NULL) {
|
|
return fText->setToStart();
|
|
}
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|
|
|
int32_t state = START_STATE;
|
|
int32_t category;
|
|
int32_t lastCategory = 0;
|
|
int32_t result = fText->getIndex();
|
|
int32_t lookaheadStatus = 0;
|
|
int32_t lookaheadResult = 0;
|
|
int32_t lookaheadTag = 0;
|
|
UChar32 c = fText->current32();
|
|
RBBIStateTableRow *row;
|
|
|
|
row = (RBBIStateTableRow *)
|
|
(this->fData->fReverseTable->fTableData + (state * fData->fReverseTable->fRowLen));
|
|
UTRIE_GET16(&fData->fTrie, c, category);
|
|
if ((category & 0x4000) != 0) {
|
|
fDictionaryCharCount++;
|
|
category &= ~0x4000;
|
|
}
|
|
|
|
if (fTrace) {
|
|
RBBIDebugPrintf("Handle Prev pos char state category \n");
|
|
}
|
|
|
|
// loop until we reach the beginning of the text or transition to state 0
|
|
for (;;) {
|
|
if (c == CharacterIterator::DONE && fText->hasPrevious()==FALSE) {
|
|
break;
|
|
}
|
|
|
|
// save the last character's category and look up the current
|
|
// character's category
|
|
lastCategory = category;
|
|
UTRIE_GET16(&fData->fTrie, c, category);
|
|
|
|
// Check the dictionary bit in the character's category.
|
|
// Counter is only used by dictionary based iterators.
|
|
//
|
|
if ((category & 0x4000) != 0) {
|
|
fDictionaryCharCount++;
|
|
category &= ~0x4000;
|
|
}
|
|
|
|
if (fTrace) {
|
|
RBBIDebugPrintf(" %4d ", fText->getIndex());
|
|
if (0x20<=c && c<0x7f) {
|
|
RBBIDebugPrintf("\"%c\" ", c);
|
|
} else {
|
|
RBBIDebugPrintf("%5x ", c);
|
|
}
|
|
RBBIDebugPrintf("%3d %3d\n", state, category);
|
|
}
|
|
|
|
// look up a state transition in the backwards state table
|
|
state = row->fNextState[category];
|
|
row = (RBBIStateTableRow *)
|
|
(this->fData->fReverseTable->fTableData + (state * fData->fReverseTable->fRowLen));
|
|
|
|
if (row->fAccepting == 0 && row->fLookAhead == 0) {
|
|
// No match, nothing of interest happening, common case.
|
|
goto continueOn;
|
|
}
|
|
|
|
if (row->fAccepting == -1) {
|
|
// Match found, common case, no lookahead involved.
|
|
result = fText->getIndex();
|
|
lookaheadStatus = 0; // clear out any pending look-ahead matches.
|
|
goto continueOn;
|
|
}
|
|
|
|
if (row->fAccepting == 0 && row->fLookAhead != 0) {
|
|
// Lookahead match point. Remember it, but only if no other rule
|
|
// has unconditionally matched to this point.
|
|
// TODO: handle case where there's a pending match from a different rule
|
|
// where lookaheadStatus != 0 && lookaheadStatus != row->fLookAhead.
|
|
int32_t r = fText->getIndex();
|
|
if (r > result) {
|
|
lookaheadResult = r;
|
|
lookaheadStatus = row->fLookAhead;
|
|
lookaheadTag = row->fTag;
|
|
}
|
|
goto continueOn;
|
|
}
|
|
|
|
if (row->fAccepting != 0 && row->fLookAhead != 0) {
|
|
// Lookahead match is completed. Set the result accordingly, but only
|
|
// if no other rule has matched further in the mean time.
|
|
if (lookaheadResult > result) {
|
|
U_ASSERT(row->fAccepting == lookaheadStatus); // TODO: handle this case
|
|
// of overlapping lookahead matches.
|
|
result = lookaheadResult;
|
|
fLastBreakTag = lookaheadTag;
|
|
lookaheadStatus = 0;
|
|
}
|
|
goto continueOn;
|
|
}
|
|
|
|
continueOn:
|
|
if (state == STOP_STATE) {
|
|
break;
|
|
}
|
|
|
|
// then advance one character backwards
|
|
c = fText->previous32();
|
|
}
|
|
|
|
// Note: the result postion isn't what is returned to the user by previous(),
|
|
// but where the implementation of previous() turns around and
|
|
// starts iterating forward again.
|
|
if (c == CharacterIterator::DONE && fText->hasPrevious()==FALSE) {
|
|
result = fText->startIndex();
|
|
}
|
|
fText->setIndex(result);
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
void
|
|
RuleBasedBreakIterator::reset()
|
|
{
|
|
// Base-class version of this function is a no-op.
|
|
// Subclasses may override with their own reset behavior.
|
|
}
|
|
|
|
|
|
|
|
//-------------------------------------------------------------------------------
|
|
//
|
|
// getRuleStatus() Return the break rule tag associated with the current
|
|
// iterator position. If the iterator arrived at its current
|
|
// position by iterating forwards, the value will have been
|
|
// cached by the handleNext() function.
|
|
//
|
|
// If no cached status value is available, the status is
|
|
// found by doing a previous() followed by a next(), which
|
|
// leaves the iterator where it started, and computes the
|
|
// status while doing the next().
|
|
//
|
|
//-------------------------------------------------------------------------------
|
|
int32_t RuleBasedBreakIterator::getRuleStatus() const {
|
|
RuleBasedBreakIterator *nonConstThis = (RuleBasedBreakIterator *)this;
|
|
if (fLastBreakTagValid == FALSE) {
|
|
// No cached status is available.
|
|
if (fText == NULL || current() == fText->startIndex()) {
|
|
// At start of text, or there is no text. Status is always zero.
|
|
nonConstThis->fLastBreakTag = 0;
|
|
nonConstThis->fLastBreakTagValid = TRUE;
|
|
} else {
|
|
// Not at start of text. Find status the tedious way.
|
|
int32_t pa = current();
|
|
nonConstThis->previous();
|
|
int32_t pb = nonConstThis->next();
|
|
U_ASSERT(pa == pb);
|
|
}
|
|
}
|
|
return nonConstThis->fLastBreakTag;
|
|
}
|
|
|
|
|
|
//-------------------------------------------------------------------------------
|
|
//
|
|
// getBinaryRules Access to the compiled form of the rules,
|
|
// for use by build system tools that save the data
|
|
// for standard iterator types.
|
|
//
|
|
//-------------------------------------------------------------------------------
|
|
const uint8_t *RuleBasedBreakIterator::getBinaryRules(uint32_t &length) {
|
|
const uint8_t *retPtr = NULL;
|
|
length = 0;
|
|
|
|
if (fData != NULL) {
|
|
retPtr = (const uint8_t *)fData->fHeader;
|
|
length = fData->fHeader->fLength;
|
|
}
|
|
return retPtr;
|
|
}
|
|
|
|
|
|
|
|
|
|
//-------------------------------------------------------------------------------
|
|
//
|
|
// BufferClone TODO: In my (Andy) opinion, this function should be deprecated.
|
|
// Saving one heap allocation isn't worth the trouble.
|
|
// Cloning shouldn't be done in tight loops, and
|
|
// making the clone copy involves other heap operations anyway.
|
|
// And the application code for correctly dealing with buffer
|
|
// size problems and the eventual object destruction is ugly.
|
|
//
|
|
//-------------------------------------------------------------------------------
|
|
BreakIterator * RuleBasedBreakIterator::createBufferClone(void *stackBuffer,
|
|
int32_t &bufferSize,
|
|
UErrorCode &status)
|
|
{
|
|
if (U_FAILURE(status)){
|
|
return NULL;
|
|
}
|
|
|
|
//
|
|
// If user buffer size is zero this is a preflight operation to
|
|
// obtain the needed buffer size, allowing for worst case misalignment.
|
|
//
|
|
if (bufferSize == 0) {
|
|
bufferSize = sizeof(RuleBasedBreakIterator) + U_ALIGNMENT_OFFSET_UP(0);
|
|
return NULL;
|
|
}
|
|
|
|
|
|
//
|
|
// Check the alignment and size of the user supplied buffer.
|
|
// Allocate heap memory if the user supplied memory is insufficient.
|
|
//
|
|
char *buf = (char *)stackBuffer;
|
|
uint32_t s = bufferSize;
|
|
|
|
if (stackBuffer == NULL) {
|
|
s = 0; // Ignore size, force allocation if user didn't give us a buffer.
|
|
}
|
|
if (U_ALIGNMENT_OFFSET(stackBuffer) != 0) {
|
|
uint32_t offsetUp = (uint32_t)U_ALIGNMENT_OFFSET_UP(buf);
|
|
s -= offsetUp;
|
|
buf += offsetUp;
|
|
}
|
|
if (s < sizeof(RuleBasedBreakIterator)) {
|
|
buf = (char *) new RuleBasedBreakIterator;
|
|
if (buf == 0) {
|
|
status = U_MEMORY_ALLOCATION_ERROR;
|
|
return NULL;
|
|
}
|
|
status = U_SAFECLONE_ALLOCATED_WARNING;
|
|
}
|
|
|
|
//
|
|
// Clone the object.
|
|
// TODO: using an overloaded operator new to directly initialize the
|
|
// copy in the user's buffer would be better, but it doesn't seem
|
|
// to get along with namespaces. Investigate why.
|
|
//
|
|
// The memcpy is only safe with an empty (default constructed)
|
|
// break iterator. Use on others can screw up reference counts
|
|
// to data. memcpy-ing objects is not really a good idea...
|
|
//
|
|
RuleBasedBreakIterator localIter; // Empty break iterator, source for memcpy
|
|
RuleBasedBreakIterator *clone = (RuleBasedBreakIterator *)buf;
|
|
uprv_memcpy(clone, &localIter, sizeof(RuleBasedBreakIterator)); // clone = empty, but initialized, iterator.
|
|
*clone = *this; // clone = the real one we want.
|
|
if (status != U_SAFECLONE_ALLOCATED_WARNING) {
|
|
clone->fBufferClone = TRUE;
|
|
}
|
|
|
|
return clone;
|
|
}
|
|
|
|
|
|
|
|
//-------------------------------------------------------------------------------
|
|
//
|
|
// isDictionaryChar Return true if the category lookup for this char
|
|
// indicates that it is in the set of dictionary lookup
|
|
// chars.
|
|
//
|
|
// This function is intended for use by dictionary based
|
|
// break iterators.
|
|
//
|
|
//-------------------------------------------------------------------------------
|
|
UBool RuleBasedBreakIterator::isDictionaryChar(UChar32 c) {
|
|
if (fData == NULL) {
|
|
return FALSE;
|
|
}
|
|
uint16_t category;
|
|
UTRIE_GET16(&fData->fTrie, c, category);
|
|
return (category & 0x4000) != 0;
|
|
}
|
|
|
|
|
|
|
|
U_NAMESPACE_END
|
|
|
|
#endif /* #if !UCONFIG_NO_BREAK_ITERATION */
|