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//
// 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 <malloc.h> // 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 &regexp, 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 &regexp,
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) {
UChar c = replacement.charAt(replIdx);
replIdx++;
if (c == BACKSLASH) {
// Backslash Escape. Copy the following char out without further checks.
// Note: Surrogate pairs don't need any special handling
// The second half wont be a '$' or a '\', and
// will move to the dest normally on the next
// loop iteration.
if (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; i<fPattern->fFrameSize; 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; i<fPattern->fPattern.length(); i++) {
printf("%c", fPattern->fPattern.charAt(i));
}
printf("\n");
printf("Input String: ");
for (i=0; i<fInput->length(); 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; i<fPattern->fDataSize; 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; i<frameSize; i++) {
newFP[i] = ((int32_t *)fp)[i];
}
fp = (REStackFrame *)newFP;
fStack->setSize(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+1<fPattern->fDataSize);
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+1<fPattern->fDataSize);
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; i<frameSize; i++) {
newFP[i] = ((int32_t *)fp)[i];
}
fp = (REStackFrame *)newFP;
fStack->setSize(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+1<fPattern->fDataSize);
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+1<fPattern->fDataSize);
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+1<fPattern->fDataSize);
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+1<fPattern->fDataSize);
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+1<fPattern->fDataSize);
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+1<fPattern->fDataSize);
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 && opValue<frameSize);
int32_t terminalIdx = fp->fExtra[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