// // file: rematch.cpp // // Contains the implementation of class RegexMatcher, // which is one of the main API classes for the ICU regular expression package. // /* ************************************************************************** * Copyright (C) 2002-2003 International Business Machines Corporation * * and others. All rights reserved. * ************************************************************************** */ #include "unicode/utypes.h" #if !UCONFIG_NO_REGULAR_EXPRESSIONS #include "unicode/regex.h" #include "unicode/uniset.h" #include "unicode/uchar.h" #include "unicode/ustring.h" #include "unicode/rbbi.h" #include "uassert.h" #include "cmemory.h" #include "uvector.h" #include "uvectr32.h" #include "regeximp.h" #include "regexst.h" // #include // Needed for heapcheck testing U_NAMESPACE_BEGIN //----------------------------------------------------------------------------- // // Constructor and Destructor // //----------------------------------------------------------------------------- RegexMatcher::RegexMatcher(const RegexPattern *pat) { fPattern = pat; fPatternOwned = NULL; fInput = NULL; fTraceDebug = FALSE; fDeferredStatus = U_ZERO_ERROR; fStack = new UVector32(fDeferredStatus); fData = fSmallData; fWordBreakItr = NULL; if (pat==NULL) { fDeferredStatus = U_ILLEGAL_ARGUMENT_ERROR; return; } if (pat->fDataSize > (int32_t)(sizeof(fSmallData)/sizeof(int32_t))) { fData = (int32_t *)uprv_malloc(pat->fDataSize * sizeof(int32_t)); } if (fStack == NULL || fData == NULL) { fDeferredStatus = U_MEMORY_ALLOCATION_ERROR; } reset(*RegexStaticSets::gStaticSets->fEmptyString); } RegexMatcher::RegexMatcher(const UnicodeString ®exp, const UnicodeString &input, uint32_t flags, UErrorCode &status) { UParseError pe; fPatternOwned = RegexPattern::compile(regexp, flags, pe, status); fPattern = fPatternOwned; fTraceDebug = FALSE; fDeferredStatus = U_ZERO_ERROR; fStack = new UVector32(status); fData = fSmallData; fWordBreakItr = NULL; if (U_FAILURE(status)) { return; } if (fPattern->fDataSize > (int32_t)(sizeof(fSmallData)/sizeof(int32_t))) { fData = (int32_t *)uprv_malloc(fPattern->fDataSize * sizeof(int32_t)); } if (fStack == NULL || fData == NULL) { status = U_MEMORY_ALLOCATION_ERROR; } reset(input); } RegexMatcher::RegexMatcher(const UnicodeString ®exp, uint32_t flags, UErrorCode &status) { UParseError pe; fTraceDebug = FALSE; fDeferredStatus = U_ZERO_ERROR; fStack = new UVector32(status); fData = fSmallData; fPatternOwned = RegexPattern::compile(regexp, flags, pe, status); fPattern = fPatternOwned; fWordBreakItr = NULL; if (U_FAILURE(status)) { return; } if (fPattern->fDataSize > (int32_t)(sizeof(fSmallData)/sizeof(int32_t))) { fData = (int32_t *)uprv_malloc(fPattern->fDataSize * sizeof(int32_t)); } if (fStack == NULL || fData == NULL) { status = U_MEMORY_ALLOCATION_ERROR; } reset(*RegexStaticSets::gStaticSets->fEmptyString); } RegexMatcher::~RegexMatcher() { delete fStack; if (fData != fSmallData) { delete fData; fData = NULL; } if (fPatternOwned) { delete fPatternOwned; fPatternOwned = NULL; fPattern = NULL; } delete fWordBreakItr; } static const UChar BACKSLASH = 0x5c; static const UChar DOLLARSIGN = 0x24; //-------------------------------------------------------------------------------- // // appendReplacement // //-------------------------------------------------------------------------------- RegexMatcher &RegexMatcher::appendReplacement(UnicodeString &dest, const UnicodeString &replacement, UErrorCode &status) { if (U_FAILURE(status)) { return *this; } if (U_FAILURE(fDeferredStatus)) { status = fDeferredStatus; return *this; } if (fMatch == FALSE) { status = U_REGEX_INVALID_STATE; return *this; } // Copy input string from the end of previous match to start of current match int32_t len = fMatchStart-fLastMatchEnd; if (len > 0) { dest.append(*fInput, fLastMatchEnd, len); } // scan the replacement text, looking for substitutions ($n) and \escapes. // TODO: optimize this loop by efficiently scanning for '$' or '\', // move entire ranges not containing substitutions. int32_t replLen = replacement.length(); int32_t replIdx = 0; while (replIdx= replLen) { break; } c = replacement.charAt(replIdx); if (c==0x55/*U*/ || c==0x75/*u*/) { // We have a \udddd or \Udddddddd escape sequence. UChar32 escapedChar = replacement.unescapeAt(replIdx); if (escapedChar != (UChar32)0xFFFFFFFF) { dest.append(escapedChar); replIdx += (c==0x55? 9: 5); // TODO: Report errors for mal-formed \u escapes? // As this is, the original sequence is output, which may be OK. continue; } } // Plain backslash escape. Just put out the escaped character. dest.append(c); replIdx++; continue; } if (c != DOLLARSIGN) { // Normal char, not a $. Copy it out without further checks. dest.append(c); continue; } // We've got a $. Pick up a capture group number if one follows. // Consume at most the number of digits necessary for the largest capture // number that is valid for this pattern. int32_t numDigits = 0; int32_t groupNum = 0; UChar32 digitC; for (;;) { if (replIdx >= replLen) { break; } digitC = replacement.char32At(replIdx); if (u_isdigit(digitC) == FALSE) { break; } replIdx = replacement.moveIndex32(replIdx, 1); groupNum=groupNum*10 + u_charDigitValue(digitC); numDigits++; if (numDigits >= fPattern->fMaxCaptureDigits) { break; } } if (numDigits == 0) { // The $ didn't introduce a group number at all. // Treat it as just part of the substitution text. dest.append(DOLLARSIGN); continue; } // Finally, append the capture group data to the destination. dest.append(group(groupNum, status)); if (U_FAILURE(status)) { // Can fail if group number is out of range. break; } } return *this; } //-------------------------------------------------------------------------------- // // appendTail Intended to be used in conjunction with appendReplacement() // To the destination string, append everything following // the last match position from the input string. // //-------------------------------------------------------------------------------- UnicodeString &RegexMatcher::appendTail(UnicodeString &dest) { int32_t len = fInput->length()-fMatchEnd; if (len > 0) { dest.append(*fInput, fMatchEnd, len); } return dest; } //-------------------------------------------------------------------------------- // // end // //-------------------------------------------------------------------------------- int32_t RegexMatcher::end(UErrorCode &err) const { return end(0, err); } int32_t RegexMatcher::end(int group, UErrorCode &err) const { if (U_FAILURE(err)) { return -1; } if (fMatch == FALSE) { err = U_REGEX_INVALID_STATE; return -1; } if (group < 0 || group > fPattern->fGroupMap->size()) { err = U_INDEX_OUTOFBOUNDS_ERROR; return -1; } int32_t e = -1; if (group == 0) { e = fMatchEnd; } else { // Get the position within the stack frame of the variables for // this capture group. int32_t groupOffset = fPattern->fGroupMap->elementAti(group-1); U_ASSERT(groupOffset < fPattern->fFrameSize); U_ASSERT(groupOffset >= 0); e = fFrame->fExtra[groupOffset + 1]; } return e; } //-------------------------------------------------------------------------------- // // find() // //-------------------------------------------------------------------------------- UBool RegexMatcher::find() { // Start at the position of the last match end. (Will be zero if the // matcher has been reset. // if (U_FAILURE(fDeferredStatus)) { return FALSE; } int32_t startPos = fMatchEnd; int32_t inputLen = fInput->length(); int32_t testLen = inputLen - fPattern->fMinMatchLen; if (startPos > testLen) { return FALSE; } const UChar *inputBuf = fInput->getBuffer(); UChar32 c; U_ASSERT(startPos >= 0); switch (fPattern->fStartType) { case START_NO_INFO: // No optimization was found. // Try a match at each input position. for (;;) { MatchAt(startPos, fDeferredStatus); if (U_FAILURE(fDeferredStatus)) { return FALSE; } if (fMatch) { return TRUE; } if (startPos >= testLen) { return FALSE; } U16_FWD_1(inputBuf, startPos, inputLen); // Note that it's perfectly OK for a pattern to have a zero-length // match at the end of a string, so we must make sure that the loop // runs with startPos == testLen the last time through. } U_ASSERT(FALSE); case START_START: // Matches are only possible at the start of the input string // (pattern begins with ^ or \A) if (startPos > 0) { return FALSE; } MatchAt(startPos, fDeferredStatus); if (U_FAILURE(fDeferredStatus)) { return FALSE; } return fMatch; case START_SET: { // Match may start on any char from a pre-computed set. U_ASSERT(fPattern->fMinMatchLen > 0); for (;;) { int32_t pos = startPos; U16_NEXT(inputBuf, startPos, inputLen, c); // like c = inputBuf[startPos++]; if (c<256 && fPattern->fInitialChars8->contains(c) || c>=256 && fPattern->fInitialChars->contains(c)) { MatchAt(pos, fDeferredStatus); if (U_FAILURE(fDeferredStatus)) { return FALSE; } if (fMatch) { return TRUE; } } if (pos >= testLen) { return FALSE; } } } U_ASSERT(FALSE); case START_STRING: case START_CHAR: { // Match starts on exactly one char. U_ASSERT(fPattern->fMinMatchLen > 0); UChar32 theChar = fPattern->fInitialChar; for (;;) { int32_t pos = startPos; U16_NEXT(inputBuf, startPos, inputLen, c); // like c = inputBuf[startPos++]; if (c == theChar) { MatchAt(pos, fDeferredStatus); if (U_FAILURE(fDeferredStatus)) { return FALSE; } if (fMatch) { return TRUE; } } if (pos >= testLen) { return FALSE; } } } U_ASSERT(FALSE); case START_LINE: { UChar32 c; if (startPos == 0) { MatchAt(startPos, fDeferredStatus); if (U_FAILURE(fDeferredStatus)) { return FALSE; } if (fMatch) { return TRUE; } U16_NEXT(inputBuf, startPos, inputLen, c); // like c = inputBuf[startPos++]; } for (;;) { UChar32 c = inputBuf[startPos-1]; if (((c & 0x7f) <= 0x29) && // First quickly bypass as many chars as possible (c == 0x0a || c==0x0c || c==0x85 ||c==0x2028 || c==0x2029 || c == 0x0d && startPos+1 < inputLen && inputBuf[startPos+1] != 0x0a)) { MatchAt(startPos, fDeferredStatus); if (U_FAILURE(fDeferredStatus)) { return FALSE; } if (fMatch) { return TRUE; } } if (startPos >= testLen) { return FALSE; } U16_NEXT(inputBuf, startPos, inputLen, c); // like c = inputBuf[startPos++]; // Note that it's perfectly OK for a pattern to have a zero-length // match at the end of a string, so we must make sure that the loop // runs with startPos == testLen the last time through. } } default: U_ASSERT(FALSE); } U_ASSERT(FALSE); return FALSE; } UBool RegexMatcher::find(int32_t start, UErrorCode &status) { if (U_FAILURE(status)) { return FALSE; } if (U_FAILURE(fDeferredStatus)) { status = fDeferredStatus; return FALSE; } int32_t inputLen = fInput->length(); if (start < 0 || start >= inputLen) { status = U_INDEX_OUTOFBOUNDS_ERROR; return FALSE; } this->reset(); fMatchEnd = start; return find(); } //-------------------------------------------------------------------------------- // // group() // //-------------------------------------------------------------------------------- UnicodeString RegexMatcher::group(UErrorCode &status) const { return group(0, status); } UnicodeString RegexMatcher::group(int32_t groupNum, UErrorCode &status) const { int32_t s = start(groupNum, status); int32_t e = end(groupNum, status); // Note: calling start() and end() above will do all necessary checking that // the group number is OK and that a match exists. status will be set. if (U_FAILURE(status)) { return UnicodeString(); } if (U_FAILURE(fDeferredStatus)) { status = fDeferredStatus; return UnicodeString(); } if (s < 0) { // A capture group wasn't part of the match return UnicodeString(); } U_ASSERT(s <= e); return UnicodeString(*fInput, s, e-s); } int32_t RegexMatcher::groupCount() const { return fPattern->fGroupMap->size(); } const UnicodeString &RegexMatcher::input() const { return *fInput; } //-------------------------------------------------------------------------------- // // lookingAt() // //-------------------------------------------------------------------------------- UBool RegexMatcher::lookingAt(UErrorCode &status) { if (U_FAILURE(status)) { return FALSE; } if (U_FAILURE(fDeferredStatus)) { status = fDeferredStatus; return FALSE; } reset(); MatchAt(0, status); return fMatch; } UBool RegexMatcher::lookingAt(int32_t start, UErrorCode &status) { if (U_FAILURE(status)) { return FALSE; } if (U_FAILURE(fDeferredStatus)) { status = fDeferredStatus; return FALSE; } if (start < 0 || start >= fInput->length()) { status = U_INDEX_OUTOFBOUNDS_ERROR; return FALSE; } reset(); MatchAt(start, status); return fMatch; } //-------------------------------------------------------------------------------- // // matches() // //-------------------------------------------------------------------------------- UBool RegexMatcher::matches(UErrorCode &status) { if (U_FAILURE(status)) { return FALSE; } if (U_FAILURE(fDeferredStatus)) { status = fDeferredStatus; return FALSE; } reset(); MatchAt(0, status); UBool success = (fMatch && fMatchEnd==fInput->length()); return success; } UBool RegexMatcher::matches(int32_t start, UErrorCode &status) { if (U_FAILURE(status)) { return FALSE; } if (U_FAILURE(fDeferredStatus)) { status = fDeferredStatus; return FALSE; } if (start < 0 || start >= fInput->length()) { status = U_INDEX_OUTOFBOUNDS_ERROR; return FALSE; } reset(); MatchAt(start, status); UBool success = (fMatch && fMatchEnd==fInput->length()); return success; } const RegexPattern &RegexMatcher::pattern() const { return *fPattern; } //-------------------------------------------------------------------------------- // // replaceAll // //-------------------------------------------------------------------------------- UnicodeString RegexMatcher::replaceAll(const UnicodeString &replacement, UErrorCode &status) { if (U_FAILURE(status)) { return *fInput; } if (U_FAILURE(fDeferredStatus)) { status = fDeferredStatus; return *fInput; } UnicodeString destString; for (reset(); find(); ) { appendReplacement(destString, replacement, status); if (U_FAILURE(status)) { break; } } appendTail(destString); return destString; } //-------------------------------------------------------------------------------- // // replaceFirst // //-------------------------------------------------------------------------------- UnicodeString RegexMatcher::replaceFirst(const UnicodeString &replacement, UErrorCode &status) { if (U_FAILURE(status)) { return *fInput; } if (U_FAILURE(fDeferredStatus)) { status = fDeferredStatus; return *fInput; } reset(); if (!find()) { return *fInput; } UnicodeString destString; appendReplacement(destString, replacement, status); appendTail(destString); return destString; } //-------------------------------------------------------------------------------- // // reset // //-------------------------------------------------------------------------------- RegexMatcher &RegexMatcher::reset() { fMatchStart = 0; fMatchEnd = 0; fLastMatchEnd = 0; fMatch = FALSE; fTouchedEnd = FALSE; resetStack(); return *this; } RegexMatcher &RegexMatcher::reset(const UnicodeString &input) { fInput = &input; reset(); if (fWordBreakItr != NULL) { fWordBreakItr->setText(input); } return *this; } RegexMatcher &RegexMatcher::reset(int32_t position, UErrorCode &status) { if (U_FAILURE(status)) { return *this; } reset(); if (position < 0 || position >= fInput->length()) { status = U_INDEX_OUTOFBOUNDS_ERROR; return *this; } fMatchEnd = position; return *this; } //-------------------------------------------------------------------------------- // // setTrace // //-------------------------------------------------------------------------------- void RegexMatcher::setTrace(UBool state) { fTraceDebug = state; } //--------------------------------------------------------------------- // // split // //--------------------------------------------------------------------- int32_t RegexMatcher::split(const UnicodeString &input, UnicodeString dest[], int32_t destCapacity, UErrorCode &status) { // // Check arguements for validity // if (U_FAILURE(status)) { return 0; }; if (destCapacity < 1) { status = U_ILLEGAL_ARGUMENT_ERROR; return 0; } // // Reset for the input text // reset(input); int32_t inputLen = input.length(); int32_t nextOutputStringStart = 0; if (inputLen == 0) { return 0; } // // Loop through the input text, searching for the delimiter pattern // int i; int32_t numCaptureGroups = fPattern->fGroupMap->size(); for (i=0; ; i++) { if (i>=destCapacity-1) { // There is one or zero output string left. // Fill the last output string with whatever is left from the input, then exit the loop. // ( i will be == destCapicity if we filled the output array while processing // capture groups of the delimiter expression, in which case we will discard the // last capture group saved in favor of the unprocessed remainder of the // input string.) i = destCapacity-1; int32_t remainingLength = inputLen-nextOutputStringStart; if (remainingLength > 0) { dest[i].setTo(input, nextOutputStringStart, remainingLength); } break; } if (find()) { // We found another delimiter. Move everything from where we started looking // up until the start of the delimiter into the next output string. int32_t fieldLen = fMatchStart - nextOutputStringStart; dest[i].setTo(input, nextOutputStringStart, fieldLen); nextOutputStringStart = fMatchEnd; // If the delimiter pattern has capturing parentheses, the captured // text goes out into the next n destination strings. int32_t groupNum; for (groupNum=1; groupNum<=numCaptureGroups; groupNum++) { if (i==destCapacity-1) { break; } i++; dest[i] = group(groupNum, status); } if (nextOutputStringStart == inputLen) { // The delimiter was at the end of the string. We're done. break; } } else { // We ran off the end of the input while looking for the next delimiter. // All the remaining text goes into the current output string. dest[i].setTo(input, nextOutputStringStart, inputLen-nextOutputStringStart); break; } } return i+1; } //-------------------------------------------------------------------------------- // // start // //-------------------------------------------------------------------------------- int32_t RegexMatcher::start(UErrorCode &status) const { return start(0, status); } int32_t RegexMatcher::start(int group, UErrorCode &status) const { if (U_FAILURE(status)) { return -1; } if (U_FAILURE(fDeferredStatus)) { status = fDeferredStatus; return -1; } if (fMatch == FALSE) { status = U_REGEX_INVALID_STATE; return -1; } if (group < 0 || group > fPattern->fGroupMap->size()) { status = U_INDEX_OUTOFBOUNDS_ERROR; return -1; } int32_t s; if (group == 0) { s = fMatchStart; } else { int32_t groupOffset = fPattern->fGroupMap->elementAti(group-1); U_ASSERT(groupOffset < fPattern->fFrameSize); U_ASSERT(groupOffset >= 0); s = fFrame->fExtra[groupOffset]; } return s; } //-------------------------------------------------------------------------------- // // touchedEnd // //-------------------------------------------------------------------------------- UBool RegexMatcher::touchedEnd() { return fTouchedEnd; } //================================================================================ // // Code following this point in this file is the internal // Match Engine Implementation. // //================================================================================ //-------------------------------------------------------------------------------- // // resetStack // Discard any previous contents of the state save stack, and initialize a // new stack frame to all -1. The -1s are needed for capture group limits, // where they indicate that a group has not yet matched anything. //-------------------------------------------------------------------------------- REStackFrame *RegexMatcher::resetStack() { // Discard any previous contents of the state save stack, and initialize a // new stack frame to all -1. The -1s are needed for capture group limits, where // they indicate that a group has not yet matched anything. fStack->removeAllElements(); int32_t *iFrame = fStack->reserveBlock(fPattern->fFrameSize, fDeferredStatus); int i; for (i=0; ifFrameSize; i++) { iFrame[i] = -1; } return (REStackFrame *)iFrame; } //-------------------------------------------------------------------------------- // // isWordBoundary // in perl, "xab..cd..", \b is true at positions 0,3,5,7 // For us, // If the current char is a combining mark, // \b is FALSE. // Else Scan backwards to the first non-combining char. // We are at a boundary if the this char and the original chars are // opposite in membership in \w set // // parameters: pos - the current position in the input buffer // //-------------------------------------------------------------------------------- UBool RegexMatcher::isWordBoundary(int32_t pos) { UBool isBoundary = FALSE; UBool cIsWord = FALSE; // Determine whether char c at current position is a member of the word set of chars. // If we're off the end of the string, behave as though we're not at a word char. if (pos < fInput->length()) { UChar32 c = fInput->char32At(pos); int8_t ctype = u_charType(c); if (ctype==U_NON_SPACING_MARK || ctype==U_ENCLOSING_MARK) { // Current char is a combining one. Not a boundary. return FALSE; } cIsWord = fPattern->fStaticSets[URX_ISWORD_SET]->contains(c); } // Back up until we come to a non-combining char, determine whether // that char is a word char. UBool prevCIsWord = FALSE; int32_t prevPos = pos; for (;;) { if (prevPos == 0) { break; } prevPos = fInput->moveIndex32(prevPos, -1); UChar32 prevChar = fInput->char32At(prevPos); int8_t prevCType = u_charType(prevChar); if (!(prevCType==U_NON_SPACING_MARK || prevCType==U_ENCLOSING_MARK)) { prevCIsWord = fPattern->fStaticSets[URX_ISWORD_SET]->contains(prevChar); break; } } isBoundary = cIsWord ^ prevCIsWord; return isBoundary; } //-------------------------------------------------------------------------------- // // isUWordBoundary // // Test for a word boundary using RBBI word break. // // parameters: pos - the current position in the input buffer // //-------------------------------------------------------------------------------- UBool RegexMatcher::isUWordBoundary(int32_t pos) { UErrorCode status=U_ZERO_ERROR; // If we haven't yet created a break iterator for this matcher, do it now. if (fWordBreakItr == NULL) { fWordBreakItr = (RuleBasedBreakIterator *)BreakIterator::createWordInstance(Locale::getEnglish(), status); if (U_FAILURE(status)) { // TODO: reliable error reporting for BI failures. return FALSE; } fWordBreakItr->setText(*fInput); } // If we are not positioned at an RBBI style boundary, \b isn't at a boundary either. if (fWordBreakItr->isBoundary(pos) == FALSE) { return FALSE; } // Discard RBBI boundaries where the "words" on both sides have the break // status of UBRK_WORD_NONE. Spaces and puncutation, for example. int32_t prevStatus = fWordBreakItr->getRuleStatus(); if (prevStatus >= UBRK_WORD_NUMBER && prevStatus < UBRK_WORD_IDEO_LIMIT) { return TRUE; } fWordBreakItr->next(); int32_t nextStatus = fWordBreakItr->getRuleStatus(); UBool returnVal = (nextStatus >= UBRK_WORD_NUMBER && nextStatus < UBRK_WORD_IDEO_LIMIT); return returnVal; } //-------------------------------------------------------------------------------- // // StateSave // Make a new stack frame, initialized as a copy of the current stack frame. // Set the pattern index in the original stack frame from the operand value // in the opcode. Execution of the engine continues with the state in // the newly created stack frame // // Note that reserveBlock() may grow the stack, resulting in the // whole thing being relocated in memory. // //-------------------------------------------------------------------------------- inline REStackFrame *RegexMatcher::StateSave(REStackFrame *fp, int32_t savePatIdx, int32_t frameSize, UErrorCode &status) { // push storage for a new frame. int32_t *newFP = fStack->reserveBlock(frameSize, status); fp = (REStackFrame *)(newFP - frameSize); // in case of realloc of stack. // New stack frame = copy of old top frame. int32_t *source = (int32_t *)fp; int32_t *dest = newFP; for (;;) { *dest++ = *source++; if (source == newFP) { break; } } fp->fPatIdx = savePatIdx; return (REStackFrame *)newFP; } //-------------------------------------------------------------------------------- // // MatchAt This is the actual matching engine. // //-------------------------------------------------------------------------------- void RegexMatcher::MatchAt(int32_t startIdx, UErrorCode &status) { UBool isMatch = FALSE; // True if the we have a match. int32_t op; // Operation from the compiled pattern, split into int32_t opType; // the opcode int32_t opValue; // and the operand value. #ifdef REGEX_RUN_DEBUG if (fTraceDebug) { printf("MatchAt(startIdx=%d)\n", startIdx); printf("Original Pattern: "); int i; for (i=0; ifPattern.length(); i++) { printf("%c", fPattern->fPattern.charAt(i)); } printf("\n"); printf("Input String: "); for (i=0; ilength(); i++) { UChar c = fInput->charAt(i); if (c<32 || c>256) { c = '.'; } printf("%c", c); } printf("\n"); printf("\n"); } #endif if (U_FAILURE(status)) { return; } fTouchedEnd = FALSE; // Cache frequently referenced items from the compiled pattern // in local variables. // int32_t *pat = fPattern->fCompiledPat->getBuffer(); const UChar *litText = fPattern->fLiteralText.getBuffer(); UVector *sets = fPattern->fSets; int32_t inputLen = fInput->length(); const UChar *inputBuf = fInput->getBuffer(); REStackFrame *fp = resetStack(); int32_t frameSize = fPattern->fFrameSize; fp->fPatIdx = 0; fp->fInputIdx = startIdx; // Zero out the pattern's static data int32_t i; for (i = 0; ifDataSize; i++) { fData[i] = 0; } // // Main loop for interpreting the compiled pattern. // One iteration of the loop per pattern operation performed. // for (;;) { #if 0 if (_heapchk() != _HEAPOK) { fprintf(stderr, "Heap Trouble\n"); } #endif op = pat[fp->fPatIdx]; opType = URX_TYPE(op); opValue = URX_VAL(op); #ifdef REGEX_RUN_DEBUG if (fTraceDebug) { printf("inputIdx=%d inputChar=%c sp=%3d ", fp->fInputIdx, fInput->char32At(fp->fInputIdx), (int32_t *)fp-fStack->getBuffer()); fPattern->dumpOp(fp->fPatIdx); } #endif fp->fPatIdx++; switch (opType) { case URX_NOP: break; case URX_BACKTRACK: // Force a backtrack. In some circumstances, the pattern compiler // will notice that the pattern can't possibly match anything, and will // emit one of these at that point. fp = (REStackFrame *)fStack->popFrame(frameSize); break; case URX_ONECHAR: if (fp->fInputIdx < inputLen) { UChar32 c; U16_NEXT(inputBuf, fp->fInputIdx, inputLen, c); if (c == opValue) { break; } } else { fTouchedEnd = TRUE; } fp = (REStackFrame *)fStack->popFrame(frameSize); break; case URX_STRING: { // Test input against a literal string. // Strings require two slots in the compiled pattern, one for the // offset to the string text, and one for the length. int32_t stringStartIdx = opValue; int32_t stringLen; op = pat[fp->fPatIdx]; // Fetch the second operand fp->fPatIdx++; opType = URX_TYPE(op); stringLen = URX_VAL(op); U_ASSERT(opType == URX_STRING_LEN); U_ASSERT(stringLen >= 2); if (fp->fInputIdx + stringLen > inputLen) { // No match. String is longer than the remaining input text. fTouchedEnd = TRUE; fp = (REStackFrame *)fStack->popFrame(frameSize); break; } const UChar * pInp = inputBuf + fp->fInputIdx; const UChar * pPat = litText+stringStartIdx; const UChar * pEnd = pInp + stringLen; for(;;) { if (*pInp == *pPat) { pInp++; pPat++; if (pInp == pEnd) { // Successful Match. fp->fInputIdx += stringLen; break; } } else { // Match failed. fp = (REStackFrame *)fStack->popFrame(frameSize); break; } } break; } break; case URX_STATE_SAVE: fp = StateSave(fp, opValue, frameSize, status); break; case URX_END: // The match loop will exit via this path on a successful match, // when we reach the end of the pattern. isMatch = TRUE; goto breakFromLoop; // Start and End Capture stack frame variables are layout out like this: // fp->fExtra[opValue] - The start of a completed capture group // opValue+1 - The end of a completed capture group // opValue+2 - the start of a capture group whose end // has not yet been reached (and might not ever be). case URX_START_CAPTURE: U_ASSERT(opValue >= 0 && opValue < frameSize-3); fp->fExtra[opValue+2] = fp->fInputIdx; break; case URX_END_CAPTURE: U_ASSERT(opValue >= 0 && opValue < frameSize-3); U_ASSERT(fp->fExtra[opValue+2] >= 0); // Start pos for this group must be set. fp->fExtra[opValue] = fp->fExtra[opValue+2]; // Tentative start becomes real. fp->fExtra[opValue+1] = fp->fInputIdx; // End position U_ASSERT(fp->fExtra[opValue] <= fp->fExtra[opValue+1]); break; case URX_DOLLAR: // $, test for End of line // or for position before new line at end of input if (fp->fInputIdx < inputLen-2) { // We are no where near the end of input. Fail. fp = (REStackFrame *)fStack->popFrame(frameSize); break; } if (fp->fInputIdx >= inputLen) { // We really are at the end of input. Success. break; } // If we are positioned just before a new-line that is located at the // end of input, succeed. if (fp->fInputIdx == inputLen-1) { UChar32 c = fInput->char32At(fp->fInputIdx); if (c == 0x0a || c==0x0d || c==0x0c || c==0x85 ||c==0x2028 || c==0x2029) { break; // At new-line at end of input. Success } } if (fp->fInputIdx == inputLen-2) { if (fInput->char32At(fp->fInputIdx) == 0x0d && fInput->char32At(fp->fInputIdx+1) == 0x0a) { break; // At CR/LF at end of input. Success } } fp = (REStackFrame *)fStack->popFrame(frameSize); break; case URX_DOLLAR_M: // $, test for End of line in multi-line mode { if (fp->fInputIdx >= inputLen) { // We really are at the end of input. Success. break; } // If we are positioned just before a new-line , succeed. // It makes no difference where the new-line is within the input. UChar32 c = inputBuf[fp->fInputIdx]; if (c == 0x0a || c==0x0d || c==0x0c || c==0x85 ||c==0x2028 || c==0x2029) { break; // At new-line at end of input. Success } // not at a new line. Fail. fp = (REStackFrame *)fStack->popFrame(frameSize); } break; case URX_CARET: // ^, test for start of line if (fp->fInputIdx != 0) { fp = (REStackFrame *)fStack->popFrame(frameSize); } break; case URX_CARET_M: // ^, test for start of line in mulit-line mode { if (fp->fInputIdx == 0) { // We are at the start input. Success. break; } // Check whether character just before the current pos is a new-line // unless we are at the end of input UChar c = inputBuf[fp->fInputIdx - 1]; if ((fp->fInputIdx < inputLen) && (c == 0x0a || c==0x0d || c==0x0c || c==0x85 ||c==0x2028 || c==0x2029)) { // It's a new-line. ^ is true. Success. break; } // Not at the start of a line. Fail. fp = (REStackFrame *)fStack->popFrame(frameSize); } break; case URX_BACKSLASH_B: // Test for word boundaries { UBool success = isWordBoundary(fp->fInputIdx); success ^= (opValue != 0); // flip sense for \B if (!success) { fp = (REStackFrame *)fStack->popFrame(frameSize); } } break; case URX_BACKSLASH_BU: // Test for word boundaries, Unicode-style { UBool success = isUWordBoundary(fp->fInputIdx); success ^= (opValue != 0); // flip sense for \B if (!success) { fp = (REStackFrame *)fStack->popFrame(frameSize); } } break; case URX_BACKSLASH_D: // Test for decimal digit { if (fp->fInputIdx >= inputLen) { fp = (REStackFrame *)fStack->popFrame(frameSize); break; } UChar32 c = fInput->char32At(fp->fInputIdx); int8_t ctype = u_charType(c); UBool success = (ctype == U_DECIMAL_DIGIT_NUMBER); success ^= (opValue != 0); // flip sense for \D if (success) { fp->fInputIdx = fInput->moveIndex32(fp->fInputIdx, 1); } else { fp = (REStackFrame *)fStack->popFrame(frameSize); } } break; case URX_BACKSLASH_G: // Test for position at end of previous match if (!((fMatch && fp->fInputIdx==fMatchEnd) || fMatch==FALSE && fp->fInputIdx==0)) { fp = (REStackFrame *)fStack->popFrame(frameSize); } break; case URX_BACKSLASH_X: // Match a Grapheme, as defined by Unicode TR 29. // Differs slightly from Perl, which consumes combining marks independently // of context. { // Fail if at end of input if (fp->fInputIdx >= inputLen) { fTouchedEnd = TRUE; fp = (REStackFrame *)fStack->popFrame(frameSize); break; } // Examine (and consume) the current char. // Dispatch into a little state machine, based on the char. UChar32 c; U16_NEXT(inputBuf, fp->fInputIdx, inputLen, c); UnicodeSet **sets = fPattern->fStaticSets; if (sets[URX_GC_NORMAL]->contains(c)) goto GC_Extend; if (sets[URX_GC_CONTROL]->contains(c)) goto GC_Control; if (sets[URX_GC_L]->contains(c)) goto GC_L; if (sets[URX_GC_LV]->contains(c)) goto GC_V; if (sets[URX_GC_LVT]->contains(c)) goto GC_T; if (sets[URX_GC_V]->contains(c)) goto GC_V; if (sets[URX_GC_T]->contains(c)) goto GC_T; goto GC_Extend; GC_L: if (fp->fInputIdx >= inputLen) goto GC_Done; U16_NEXT(inputBuf, fp->fInputIdx, inputLen, c); if (sets[URX_GC_L]->contains(c)) goto GC_L; if (sets[URX_GC_LV]->contains(c)) goto GC_V; if (sets[URX_GC_LVT]->contains(c)) goto GC_T; if (sets[URX_GC_V]->contains(c)) goto GC_V; U16_PREV(inputBuf, 0, fp->fInputIdx, c); goto GC_Extend; GC_V: if (fp->fInputIdx >= inputLen) goto GC_Done; U16_NEXT(inputBuf, fp->fInputIdx, inputLen, c); if (sets[URX_GC_V]->contains(c)) goto GC_V; if (sets[URX_GC_T]->contains(c)) goto GC_T; U16_PREV(inputBuf, 0, fp->fInputIdx, c); goto GC_Extend; GC_T: if (fp->fInputIdx >= inputLen) goto GC_Done; U16_NEXT(inputBuf, fp->fInputIdx, inputLen, c); if (sets[URX_GC_T]->contains(c)) goto GC_T; U16_PREV(inputBuf, 0, fp->fInputIdx, c); goto GC_Extend; GC_Extend: // Combining characters are consumed here for (;;) { if (fp->fInputIdx >= inputLen) { break; } U16_GET(inputBuf, 0, fp->fInputIdx, inputLen, c); if (sets[URX_GC_EXTEND]->contains(c) == FALSE) { break; } U16_FWD_1(inputBuf, fp->fInputIdx, inputLen); } goto GC_Done; GC_Control: // Most control chars stand alone (don't combine with combining chars), // except for that CR/LF sequence is a single grapheme cluster. if (c == 0x0d && fp->fInputIdx < inputLen && inputBuf[fp->fInputIdx] == 0x0a) { fp->fInputIdx++; } GC_Done: break; } case URX_BACKSLASH_Z: // Test for end of line if (fp->fInputIdx < inputLen) { fp = (REStackFrame *)fStack->popFrame(frameSize); } break; case URX_STATIC_SETREF: { // Test input character against one of the predefined sets // (Word Characters, for example) // The high bit of the op value is a flag for the match polarity. // 0: success if input char is in set. // 1: success if input char is not in set. if (fp->fInputIdx >= inputLen) { fTouchedEnd = TRUE; fp = (REStackFrame *)fStack->popFrame(frameSize); break; } UBool success = ((opValue & URX_NEG_SET) == URX_NEG_SET); opValue &= ~URX_NEG_SET; U_ASSERT(opValue > 0 && opValue < URX_LAST_SET); UChar32 c; U16_NEXT(inputBuf, fp->fInputIdx, inputLen, c); if (c < 256) { Regex8BitSet *s8 = &fPattern->fStaticSets8[opValue]; if (s8->contains(c)) { success = !success; } } else { const UnicodeSet *s = fPattern->fStaticSets[opValue]; if (s->contains(c)) { success = !success; } } if (!success) { fp = (REStackFrame *)fStack->popFrame(frameSize); } } break; case URX_STAT_SETREF_N: { // Test input character for NOT being a member of one of // the predefined sets (Word Characters, for example) if (fp->fInputIdx >= inputLen) { fTouchedEnd = TRUE; fp = (REStackFrame *)fStack->popFrame(frameSize); break; } U_ASSERT(opValue > 0 && opValue < URX_LAST_SET); UChar32 c; U16_NEXT(inputBuf, fp->fInputIdx, inputLen, c); if (c < 256) { Regex8BitSet *s8 = &fPattern->fStaticSets8[opValue]; if (s8->contains(c) == FALSE) { break; } } else { const UnicodeSet *s = fPattern->fStaticSets[opValue]; if (s->contains(c) == FALSE) { break; } } fp = (REStackFrame *)fStack->popFrame(frameSize); } break; case URX_SETREF: if (fp->fInputIdx < inputLen) { // There is input left. Pick up one char and test it for set membership. UChar32 c; U16_NEXT(inputBuf, fp->fInputIdx, inputLen, c); U_ASSERT(opValue > 0 && opValue < sets->size()); if (c<256) { Regex8BitSet *s8 = &fPattern->fSets8[opValue]; if (s8->contains(c)) { break; } } else { UnicodeSet *s = (UnicodeSet *)sets->elementAt(opValue); if (s->contains(c)) { // The character is in the set. A Match. break; } } } else { fTouchedEnd = TRUE; } // Either at end of input, or the character wasn't in the set. // Either way, we need to back track out. fp = (REStackFrame *)fStack->popFrame(frameSize); break; case URX_DOTANY: { // . matches anything, but stops at end-of-line. if (fp->fInputIdx >= inputLen) { // At end of input. Match failed. Backtrack out. fTouchedEnd = TRUE; fp = (REStackFrame *)fStack->popFrame(frameSize); break; } // There is input left. Advance over one char, unless we've hit end-of-line UChar32 c; U16_NEXT(inputBuf, fp->fInputIdx, inputLen, c); if (((c & 0x7f) <= 0x29) && // First quickly bypass as many chars as possible (c == 0x0a || c==0x0d || c==0x0c || c==0x85 ||c==0x2028 || c==0x2029)) { // End of line in normal mode. . does not match. fp = (REStackFrame *)fStack->popFrame(frameSize); break; } } break; case URX_DOTANY_ALL: { // ., in dot-matches-all (including new lines) mode if (fp->fInputIdx >= inputLen) { // At end of input. Match failed. Backtrack out. fTouchedEnd = TRUE; fp = (REStackFrame *)fStack->popFrame(frameSize); break; } // There is input left. Advance over one char, except if we are // at a cr/lf, advance over both of them. UChar32 c; U16_NEXT(inputBuf, fp->fInputIdx, inputLen, c); if (c==0x0d) { // In the case of a CR/LF, we need to advance over both. UChar nextc = inputBuf[fp->fInputIdx]; if (nextc == 0x0a) { fp->fInputIdx++; } } } break; case URX_DOTANY_PL: // Match all up to and end-of-line or end-of-input. { // Fail if input already exhausted. if (fp->fInputIdx >= inputLen) { fTouchedEnd = TRUE; fp = (REStackFrame *)fStack->popFrame(frameSize); break; } // There is input left. Fail if we are at the end of a line. UChar32 c; U16_NEXT(inputBuf, fp->fInputIdx, inputLen, c); if (((c & 0x7f) <= 0x29) && // First quickly bypass as many chars as possible (c == 0x0a || c==0x0d || c==0x0c || c==0x85 ||c==0x2028 || c==0x2029)) { // End of line in normal mode. . does not match. fp = (REStackFrame *)fStack->popFrame(frameSize); break; } // There was input left. Consume it until we hit the end of a line, // or until it's exhausted. while (fp->fInputIdx < inputLen) { U16_NEXT(inputBuf, fp->fInputIdx, inputLen, c); if (((c & 0x7f) <= 0x29) && // First quickly bypass as many chars as possible (c == 0x0a || c==0x0d || c==0x0c || c==0x85 ||c==0x2028 || c==0x2029)) { U16_BACK_1(inputBuf, 0, fp->fInputIdx) // Scan has reached a line-end. We are done. break; } } } break; case URX_DOTANY_ALL_PL: { // Match up to end of input. Fail if already at end of input. if (fp->fInputIdx >= inputLen) { fTouchedEnd = TRUE; fp = (REStackFrame *)fStack->popFrame(frameSize); } else { fp->fInputIdx = inputLen; } } break; case URX_JMP: fp->fPatIdx = opValue; break; case URX_FAIL: isMatch = FALSE; goto breakFromLoop; case URX_JMP_SAV: U_ASSERT(opValue < fPattern->fCompiledPat->size()); fp = StateSave(fp, fp->fPatIdx, frameSize, status); // State save to loc following current fp->fPatIdx = opValue; // Then JMP. break; case URX_JMP_SAV_X: // This opcode is used with (x)+, when x can match a zero length string. // Same as JMP_SAV, except conditional on the match having made forward progress. // Destination of the JMP must be a URX_STO_INP_LOC, from which we get the // data address of the input position at the start of the loop. { U_ASSERT(opValue > 0 && opValue < fPattern->fCompiledPat->size()); int32_t stoOp = pat[opValue-1]; U_ASSERT(URX_TYPE(stoOp) == URX_STO_INP_LOC); int32_t frameLoc = URX_VAL(stoOp); U_ASSERT(frameLoc >= 0 && frameLoc < frameSize); int32_t prevInputIdx = fp->fExtra[frameLoc]; U_ASSERT(prevInputIdx <= fp->fInputIdx); if (prevInputIdx < fp->fInputIdx) { // The match did make progress. Repeat the loop. fp = StateSave(fp, fp->fPatIdx, frameSize, status); // State save to loc following current fp->fPatIdx = opValue; fp->fExtra[frameLoc] = fp->fInputIdx; } // If the input position did not advance, we do nothing here, // execution will fall out of the loop. } break; case URX_CTR_INIT: { U_ASSERT(opValue >= 0 && opValue < frameSize-2); fp->fExtra[opValue] = 0; // Set the loop counter variable to zero // Pick up the three extra operands that CTR_INIT has, and // skip the pattern location counter past int32_t instrOperandLoc = fp->fPatIdx; fp->fPatIdx += 3; int32_t loopLoc = URX_VAL(pat[instrOperandLoc]); int32_t minCount = pat[instrOperandLoc+1]; int32_t maxCount = pat[instrOperandLoc+2]; U_ASSERT(minCount>=0); U_ASSERT(maxCount>=minCount || maxCount==-1); U_ASSERT(loopLoc>fp->fPatIdx); if (minCount == 0) { fp = StateSave(fp, loopLoc+1, frameSize, status); } if (maxCount == 0) { fp = (REStackFrame *)fStack->popFrame(frameSize); } } break; case URX_CTR_LOOP: { U_ASSERT(opValue>0 && opValue < fp->fPatIdx-2); int32_t initOp = pat[opValue]; U_ASSERT(URX_TYPE(initOp) == URX_CTR_INIT); int32_t *pCounter = &fp->fExtra[URX_VAL(initOp)]; int32_t minCount = pat[opValue+2]; int32_t maxCount = pat[opValue+3]; // Increment the counter. Note: we're not worrying about counter // overflow, since the data comes from UnicodeStrings, which // stores its length in an int32_t. (*pCounter)++; U_ASSERT(*pCounter > 0); if ((uint32_t)*pCounter >= (uint32_t)maxCount) { U_ASSERT(*pCounter == maxCount || maxCount == -1); break; } if (*pCounter >= minCount) { fp = StateSave(fp, fp->fPatIdx, frameSize, status); } fp->fPatIdx = opValue + 4; // Loop back. } break; case URX_CTR_INIT_NG: { U_ASSERT(opValue >= 0 && opValue < frameSize-2); fp->fExtra[opValue] = 0; // Set the loop counter variable to zero // Pick up the three extra operands that CTR_INIT has, and // skip the pattern location counter past int32_t instrOperandLoc = fp->fPatIdx; fp->fPatIdx += 3; int32_t loopLoc = URX_VAL(pat[instrOperandLoc]); int32_t minCount = pat[instrOperandLoc+1]; int32_t maxCount = pat[instrOperandLoc+2]; U_ASSERT(minCount>=0); U_ASSERT(maxCount>=minCount || maxCount==-1); U_ASSERT(loopLoc>fp->fPatIdx); if (minCount == 0) { if (maxCount != 0) { fp = StateSave(fp, fp->fPatIdx, frameSize, status); } fp->fPatIdx = loopLoc+1; // Continue with stuff after repeated block } } break; case URX_CTR_LOOP_NG: { U_ASSERT(opValue>0 && opValue < fp->fPatIdx-2); int32_t initOp = pat[opValue]; U_ASSERT(URX_TYPE(initOp) == URX_CTR_INIT_NG); int32_t *pCounter = &fp->fExtra[URX_VAL(initOp)]; int32_t minCount = pat[opValue+2]; int32_t maxCount = pat[opValue+3]; // Increment the counter. Note: we're not worrying about counter // overflow, since the data comes from UnicodeStrings, which // stores its length in an int32_t. (*pCounter)++; U_ASSERT(*pCounter > 0); if ((uint32_t)*pCounter >= (uint32_t)maxCount) { // The loop has matched the maximum permitted number of times. // Break out of here with no action. Matching will // continue with the following pattern. U_ASSERT(*pCounter == maxCount || maxCount == -1); break; } if (*pCounter < minCount) { // We haven't met the minimum number of matches yet. // Loop back for another one. fp->fPatIdx = opValue + 4; // Loop back. } else { // We do have the minimum number of matches. // Fall into the following pattern, but first do // a state save to the top of the loop, so that a failure // in the following pattern will try another iteration of the loop. fp = StateSave(fp, opValue + 4, frameSize, status); } } break; // TODO: Possessive flavor of loop ops, or take them out if no longer needed. case URX_STO_SP: U_ASSERT(opValue >= 0 && opValue < fPattern->fDataSize); fData[opValue] = fStack->size(); break; case URX_LD_SP: { U_ASSERT(opValue >= 0 && opValue < fPattern->fDataSize); int32_t newStackSize = fData[opValue]; U_ASSERT(newStackSize <= fStack->size()); int32_t *newFP = fStack->getBuffer() + newStackSize - frameSize; if (newFP == (int32_t *)fp) { break; } int32_t i; for (i=0; isetSize(newStackSize); } break; case URX_BACKREF: case URX_BACKREF_I: { U_ASSERT(opValue < frameSize); int32_t groupStartIdx = fp->fExtra[opValue]; int32_t groupEndIdx = fp->fExtra[opValue+1]; U_ASSERT(groupStartIdx <= groupEndIdx); int32_t len = groupEndIdx-groupStartIdx; if (groupStartIdx < 0) { // This capture group has not participated in the match thus far, fp = (REStackFrame *)fStack->popFrame(frameSize); // FAIL, no match. } if (len == 0) { // The capture group match was of an empty string. // Verified by testing: Perl matches succeed in this case, so // we do too. break; } UBool haveMatch = FALSE; if (fp->fInputIdx + len <= inputLen) { if (opType == URX_BACKREF) { if (u_strncmp(inputBuf+groupStartIdx, inputBuf+fp->fInputIdx, len) == 0) { haveMatch = TRUE; } } else { if (u_strncasecmp(inputBuf+groupStartIdx, inputBuf+fp->fInputIdx, len, U_FOLD_CASE_DEFAULT) == 0) { haveMatch = TRUE; } } } else { fTouchedEnd = TRUE; } if (haveMatch) { fp->fInputIdx += len; // Match. Advance current input position. } else { fp = (REStackFrame *)fStack->popFrame(frameSize); // FAIL, no match. } } break; case URX_STO_INP_LOC: { U_ASSERT(opValue >= 0 && opValue < frameSize); fp->fExtra[opValue] = fp->fInputIdx; } break; case URX_JMPX: { int32_t instrOperandLoc = fp->fPatIdx; fp->fPatIdx += 1; int32_t dataLoc = URX_VAL(pat[instrOperandLoc]); U_ASSERT(dataLoc >= 0 && dataLoc < frameSize); int32_t savedInputIdx = fp->fExtra[dataLoc]; U_ASSERT(savedInputIdx <= fp->fInputIdx); if (savedInputIdx < fp->fInputIdx) { fp->fPatIdx = opValue; // JMP } else { fp = (REStackFrame *)fStack->popFrame(frameSize); // FAIL, no progress in loop. } } break; case URX_LA_START: { // Entering a lookahead block. // Save Stack Ptr, Input Pos. U_ASSERT(opValue>=0 && opValue+1fDataSize); fData[opValue] = fStack->size(); fData[opValue+1] = fp->fInputIdx; } break; case URX_LA_END: { // Leaving a look-ahead block. // restore Stack Ptr, Input Pos to positions they had on entry to block. U_ASSERT(opValue>=0 && opValue+1fDataSize); int32_t stackSize = fStack->size(); int32_t newStackSize = fData[opValue]; U_ASSERT(stackSize >= newStackSize); if (stackSize > newStackSize) { int32_t *newFP = fStack->getBuffer() + newStackSize - frameSize; int32_t i; for (i=0; isetSize(newStackSize); } fp->fInputIdx = fData[opValue+1]; } break; case URX_ONECHAR_I: if (fp->fInputIdx < inputLen) { UChar32 c; U16_NEXT(inputBuf, fp->fInputIdx, inputLen, c); if (u_foldCase(c, U_FOLD_CASE_DEFAULT) == opValue) { break; } } else { fTouchedEnd = TRUE; } fp = (REStackFrame *)fStack->popFrame(frameSize); break; case URX_STRING_I: { // Test input against a literal string. // Strings require two slots in the compiled pattern, one for the // offset to the string text, and one for the length. int32_t stringStartIdx, stringLen; stringStartIdx = opValue; op = pat[fp->fPatIdx]; fp->fPatIdx++; opType = URX_TYPE(op); opValue = URX_VAL(op); U_ASSERT(opType == URX_STRING_LEN); stringLen = opValue; int32_t stringEndIndex = fp->fInputIdx + stringLen; if (stringEndIndex <= inputLen) { if (u_strncasecmp(inputBuf+fp->fInputIdx, litText+stringStartIdx, stringLen, U_FOLD_CASE_DEFAULT) == 0) { // Success. Advance the current input position. fp->fInputIdx = stringEndIndex; break; } } else { fTouchedEnd = TRUE; } // No match. Back up matching to a saved state fp = (REStackFrame *)fStack->popFrame(frameSize); } break; case URX_LB_START: { // Entering a look-behind block. // Save Stack Ptr, Input Pos. U_ASSERT(opValue>=0 && opValue+1fDataSize); fData[opValue] = fStack->size(); fData[opValue+1] = fp->fInputIdx; // Init the variable containing the start index for attempted matches. fData[opValue+2] = -1; // Save input string length, then reset to pin any matches to end at // the current position. fData[opValue+3] = inputLen; inputLen = fp->fInputIdx; } break; case URX_LB_CONT: { // Positive Look-Behind, at top of loop checking for matches of LB expression // at all possible input starting positions. // Fetch the min and max possible match lengths. They are the operands // of this op in the pattern. int32_t minML = pat[fp->fPatIdx++]; int32_t maxML = pat[fp->fPatIdx++]; U_ASSERT(minML <= maxML); U_ASSERT(minML >= 0); // Fetch (from data) the last input index where a match was attempted. U_ASSERT(opValue>=0 && opValue+1fDataSize); int32_t *lbStartIdx = &fData[opValue+2]; if (*lbStartIdx < 0) { // First time through loop. *lbStartIdx = fp->fInputIdx - minML; } else { // 2nd through nth time through the loop. // Back up start position for match by one. if (*lbStartIdx == 0) { (*lbStartIdx)--; // Because U16_BACK is unsafe starting at 0. } else { U16_BACK_1(inputBuf, 0, *lbStartIdx); } } if (*lbStartIdx < 0 || *lbStartIdx < fp->fInputIdx - maxML) { // We have tried all potential match starting points without // getting a match. Backtrack out, and out of the // Look Behind altogether. fp = (REStackFrame *)fStack->popFrame(frameSize); int32_t restoreInputLen = fData[opValue+3]; U_ASSERT(restoreInputLen >= inputLen); U_ASSERT(restoreInputLen <= fInput->length()); inputLen = restoreInputLen; break; } // Save state to this URX_LB_CONT op, so failure to match will repeat the loop. // (successful match will fall off the end of the loop.) fp = StateSave(fp, fp->fPatIdx-3, frameSize, status); fp->fInputIdx = *lbStartIdx; } break; case URX_LB_END: // End of a look-behind block, after a successful match. { U_ASSERT(opValue>=0 && opValue+1fDataSize); if (fp->fInputIdx != inputLen) { // The look-behind expression matched, but the match did not // extend all the way to the point that we are looking behind from. // FAIL out of here, which will take us back to the LB_CONT, which // will retry the match starting at another position or fail // the look-behind altogether, whichever is appropriate. fp = (REStackFrame *)fStack->popFrame(frameSize); break; } // Look-behind match is good. Restore the orignal input string length, // which had been truncated to pin the end of the lookbehind match to the // position being looked-behind. int32_t originalInputLen = fData[opValue+3]; U_ASSERT(originalInputLen >= inputLen); U_ASSERT(originalInputLen <= fInput->length()); inputLen = originalInputLen; } break; case URX_LBN_CONT: { // Negative Look-Behind, at top of loop checking for matches of LB expression // at all possible input starting positions. // Fetch the extra parameters of this op. int32_t minML = pat[fp->fPatIdx++]; int32_t maxML = pat[fp->fPatIdx++]; int32_t continueLoc = pat[fp->fPatIdx++]; continueLoc = URX_VAL(continueLoc); U_ASSERT(minML <= maxML); U_ASSERT(minML >= 0); U_ASSERT(continueLoc > fp->fPatIdx); // Fetch (from data) the last input index where a match was attempted. U_ASSERT(opValue>=0 && opValue+1fDataSize); int32_t *lbStartIdx = &fData[opValue+2]; if (*lbStartIdx < 0) { // First time through loop. *lbStartIdx = fp->fInputIdx - minML; } else { // 2nd through nth time through the loop. // Back up start position for match by one. if (*lbStartIdx == 0) { (*lbStartIdx)--; // Because U16_BACK is unsafe starting at 0. } else { U16_BACK_1(inputBuf, 0, *lbStartIdx); } } if (*lbStartIdx < 0 || *lbStartIdx < fp->fInputIdx - maxML) { // We have tried all potential match starting points without // getting a match, which means that the negative lookbehind as // a whole has succeeded. Jump forward to the continue location int32_t restoreInputLen = fData[opValue+3]; U_ASSERT(restoreInputLen >= inputLen); U_ASSERT(restoreInputLen <= fInput->length()); inputLen = restoreInputLen; fp->fPatIdx = continueLoc; break; } // Save state to this URX_LB_CONT op, so failure to match will repeat the loop. // (successful match will cause a FAIL out of the loop altogether.) fp = StateSave(fp, fp->fPatIdx-4, frameSize, status); fp->fInputIdx = *lbStartIdx; } break; case URX_LBN_END: // End of a negative look-behind block, after a successful match. { U_ASSERT(opValue>=0 && opValue+1fDataSize); if (fp->fInputIdx != inputLen) { // The look-behind expression matched, but the match did not // extend all the way to the point that we are looking behind from. // FAIL out of here, which will take us back to the LB_CONT, which // will retry the match starting at another position or succeed // the look-behind altogether, whichever is appropriate. fp = (REStackFrame *)fStack->popFrame(frameSize); break; } // Look-behind expression matched, which means look-behind test as // a whole Fails // Restore the orignal input string length, which had been truncated // inorder to pin the end of the lookbehind match // to the position being looked-behind. int32_t originalInputLen = fData[opValue+3]; U_ASSERT(originalInputLen >= inputLen); U_ASSERT(originalInputLen <= fInput->length()); inputLen = originalInputLen; // Restore original stack position, discarding any state saved // by the successful pattern match. U_ASSERT(opValue>=0 && opValue+1fDataSize); int32_t newStackSize = fData[opValue]; U_ASSERT(fStack->size() > newStackSize); fStack->setSize(newStackSize); // FAIL, which will take control back to someplace // prior to entering the look-behind test. fp = (REStackFrame *)fStack->popFrame(frameSize); } break; case URX_LOOP_SR_I: // Loop Initialization for the optimized implementation of // [some character set]* // This op scans through all matching input. // The following LOOP_C op emulates stack unwinding if the following pattern fails. { U_ASSERT(opValue > 0 && opValue < sets->size()); Regex8BitSet *s8 = &fPattern->fSets8[opValue]; UnicodeSet *s = (UnicodeSet *)sets->elementAt(opValue); // Loop through input, until either the input is exhausted or // we reach a character that is not a member of the set. int32_t ix = fp->fInputIdx; for (;;) { if (ix >= inputLen) { fTouchedEnd = TRUE; break; } UChar32 c; U16_NEXT(inputBuf, ix, inputLen, c); if (c<256) { if (s8->contains(c) == FALSE) { U16_BACK_1(inputBuf, 0, ix); break; } } else { if (s->contains(c) == FALSE) { U16_BACK_1(inputBuf, 0, ix); break; } } } // If there were no matching characters, skip over the loop altogether. // The loop doesn't run at all, a * op always succeeds. if (ix == fp->fInputIdx) { fp->fPatIdx++; // skip the URX_LOOP_C op. break; } // Peek ahead in the compiled pattern, to the URX_LOOP_C that // must follow. It's operand is the stack location // that holds the starting input index for the match of this [set]* int32_t loopcOp = pat[fp->fPatIdx]; U_ASSERT(URX_TYPE(loopcOp) == URX_LOOP_C); int32_t stackLoc = URX_VAL(loopcOp); U_ASSERT(stackLoc >= 0 && stackLoc < frameSize); fp->fExtra[stackLoc] = fp->fInputIdx; fp->fInputIdx = ix; // Save State to the URX_LOOP_C op that follows this one, // so that match failures in the following code will return to there. // Then bump the pattern idx so the LOOP_C is skipped on the way out of here. fp = StateSave(fp, fp->fPatIdx, frameSize, status); fp->fPatIdx++; } break; case URX_LOOP_DOT_I: // Loop Initialization for the optimized implementation of .* // This op scans through all remaining input. // The following LOOP_C op emulates stack unwinding if the following pattern fails. { // Loop through input until the input is exhausted (we reach an end-of-line) // In multi-line mode, we can just go straight to the end of the input. int32_t ix; if (opValue == 1) { // Multi-line mode. ix = inputLen; fTouchedEnd = TRUE; } else { // NOT multi-line mode. Line endings do not match '.' // Scan forward until a line ending or end of input. ix = fp->fInputIdx; for (;;) { if (ix >= inputLen) { ix = inputLen; fTouchedEnd = TRUE; break; } UChar32 c; U16_NEXT(inputBuf, ix, inputLen, c); // c = inputBuf[ix++] if (((c & 0x7f) <= 0x29) && (c == 0x0a || c==0x0d || c==0x0c || c==0x85 ||c==0x2028 || c==0x2029)) { // char is a line ending. Put the input pos back to the // line ending char, and exit the scanning loop. U16_BACK_1(inputBuf, 0, ix); break; } } } // If there were no matching characters, skip over the loop altogether. // The loop doesn't run at all, a * op always succeeds. if (ix == fp->fInputIdx) { fp->fPatIdx++; // skip the URX_LOOP_C op. break; } // Peek ahead in the compiled pattern, to the URX_LOOP_C that // must follow. It's operand is the stack location // that holds the starting input index for the match of this [set]* int32_t loopcOp = pat[fp->fPatIdx]; U_ASSERT(URX_TYPE(loopcOp) == URX_LOOP_C); int32_t stackLoc = URX_VAL(loopcOp); U_ASSERT(stackLoc >= 0 && stackLoc < frameSize); fp->fExtra[stackLoc] = fp->fInputIdx; fp->fInputIdx = ix; // Save State to the URX_LOOP_C op that follows this one, // so that match failures in the following code will return to there. // Then bump the pattern idx so the LOOP_C is skipped on the way out of here. fp = StateSave(fp, fp->fPatIdx, frameSize, status); fp->fPatIdx++; } break; case URX_LOOP_C: { U_ASSERT(opValue>=0 && opValuefExtra[opValue]; U_ASSERT(terminalIdx <= fp->fInputIdx); if (terminalIdx == fp->fInputIdx) { // We've backed up the input idx to the point that the loop started. // The loop is done. Leave here without saving state. // Subsequent failures won't come back here. break; } // Set up for the next iteration of the loop, with input index // backed up by one from the last time through, // and a state save to this instruction in case the following code fails again. // (We're going backwards because this loop emulates stack unwinding, not // the initial scan forward.) U_ASSERT(fp->fInputIdx > 0); U16_BACK_1(inputBuf, 0, fp->fInputIdx); if (inputBuf[fp->fInputIdx] == 0x0a && fp->fInputIdx > terminalIdx && inputBuf[fp->fInputIdx-1] == 0x0d) { int32_t prevOp = pat[fp->fPatIdx-2]; if (URX_TYPE(prevOp) == URX_LOOP_DOT_I) { // .*, stepping back over CRLF pair. fp->fInputIdx--; } } fp = StateSave(fp, fp->fPatIdx-1, frameSize, status); } break; default: // Trouble. The compiled pattern contains an entry with an // unrecognized type tag. U_ASSERT(FALSE); } if (U_FAILURE(status)) { break; } } breakFromLoop: fMatch = isMatch; if (isMatch) { fLastMatchEnd = fMatchEnd; fMatchStart = startIdx; fMatchEnd = fp->fInputIdx; if (fTraceDebug) { REGEX_RUN_DEBUG_PRINTF("Match. start=%d end=%d\n\n", fMatchStart, fMatchEnd); } } else { if (fTraceDebug) { REGEX_RUN_DEBUG_PRINTF("No match\n\n"); } } fFrame = fp; // The active stack frame when the engine stopped. // Contains the capture group results that we need to // access later. return; } UOBJECT_DEFINE_RTTI_IMPLEMENTATION(RegexMatcher) U_NAMESPACE_END #endif // !UCONFIG_NO_REGULAR_EXPRESSIONS