/* * Copyright (C) 2008, 2009 Apple Inc. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include "config.h" #include "CharacterClassConstructor.h" #if ENABLE(WREC) #include "pcre_internal.h" #include <wtf/ASCIICType.h> using namespace WTF; namespace JSC { namespace WREC { void CharacterClassConstructor::addSorted(Vector<UChar>& matches, UChar ch) { unsigned pos = 0; unsigned range = matches.size(); // binary chop, find position to insert char. while (range) { unsigned index = range >> 1; int val = matches[pos+index] - ch; if (!val) return; else if (val > 0) range = index; else { pos += (index+1); range -= (index+1); } } if (pos == matches.size()) matches.append(ch); else matches.insert(pos, ch); } void CharacterClassConstructor::addSortedRange(Vector<CharacterRange>& ranges, UChar lo, UChar hi) { unsigned end = ranges.size(); // Simple linear scan - I doubt there are that many ranges anyway... // feel free to fix this with something faster (eg binary chop). for (unsigned i = 0; i < end; ++i) { // does the new range fall before the current position in the array if (hi < ranges[i].begin) { // optional optimization: concatenate appending ranges? - may not be worthwhile. if (hi == (ranges[i].begin - 1)) { ranges[i].begin = lo; return; } CharacterRange r = {lo, hi}; ranges.insert(i, r); return; } // Okay, since we didn't hit the last case, the end of the new range is definitely at or after the begining // If the new range start at or before the end of the last range, then the overlap (if it starts one after the // end of the last range they concatenate, which is just as good. if (lo <= (ranges[i].end + 1)) { // found an intersect! we'll replace this entry in the array. ranges[i].begin = std::min(ranges[i].begin, lo); ranges[i].end = std::max(ranges[i].end, hi); // now check if the new range can subsume any subsequent ranges. unsigned next = i+1; // each iteration of the loop we will either remove something from the list, or break the loop. while (next < ranges.size()) { if (ranges[next].begin <= (ranges[i].end + 1)) { // the next entry now overlaps / concatenates this one. ranges[i].end = std::max(ranges[i].end, ranges[next].end); ranges.remove(next); } else break; } return; } } // CharacterRange comes after all existing ranges. CharacterRange r = {lo, hi}; ranges.append(r); } void CharacterClassConstructor::put(UChar ch) { // Parsing a regular expression like [a-z], we start in an initial empty state: // ((m_charBuffer == -1) && !m_isPendingDash) // When buffer the 'a' sice it may be (and is in this case) part of a range: // ((m_charBuffer != -1) && !m_isPendingDash) // Having parsed the hyphen we then record that the dash is also pending: // ((m_charBuffer != -1) && m_isPendingDash) // The next change will always take us back to the initial state - either because // a complete range has been parsed (such as [a-z]), or because a flush is forced, // due to an early end in the regexp ([a-]), or a character class escape being added // ([a-\s]). The fourth permutation of m_charBuffer and m_isPendingDash is not permitted. ASSERT(!((m_charBuffer == -1) && m_isPendingDash)); if (m_charBuffer != -1) { if (m_isPendingDash) { // EXAMPLE: parsing [-a-c], the 'c' reaches this case - we have buffered a previous character and seen a hyphen, so this is a range. UChar lo = m_charBuffer; UChar hi = ch; // Reset back to the inital state. m_charBuffer = -1; m_isPendingDash = false; // This is an error, detected lazily. Do not proceed. if (lo > hi) { m_isUpsideDown = true; return; } if (lo <= 0x7f) { char asciiLo = lo; char asciiHi = std::min(hi, (UChar)0x7f); addSortedRange(m_ranges, lo, asciiHi); if (m_isCaseInsensitive) { if ((asciiLo <= 'Z') && (asciiHi >= 'A')) addSortedRange(m_ranges, std::max(asciiLo, 'A')+('a'-'A'), std::min(asciiHi, 'Z')+('a'-'A')); if ((asciiLo <= 'z') && (asciiHi >= 'a')) addSortedRange(m_ranges, std::max(asciiLo, 'a')+('A'-'a'), std::min(asciiHi, 'z')+('A'-'a')); } } if (hi >= 0x80) { UChar unicodeCurr = std::max(lo, (UChar)0x80); addSortedRange(m_rangesUnicode, unicodeCurr, hi); if (m_isCaseInsensitive) { // we're going to scan along, updating the start of the range while (unicodeCurr <= hi) { // Spin forwards over any characters that don't have two cases. for (; jsc_pcre_ucp_othercase(unicodeCurr) == -1; ++unicodeCurr) { // if this was the last character in the range, we're done. if (unicodeCurr == hi) return; } // if we fall through to here, unicodeCurr <= hi & has another case. Get the other case. UChar rangeStart = unicodeCurr; UChar otherCurr = jsc_pcre_ucp_othercase(unicodeCurr); // If unicodeCurr is not yet hi, check the next char in the range. If it also has another case, // and if it's other case value is one greater then the othercase value for the current last // character included in the range, we can include next into the range. while ((unicodeCurr < hi) && (jsc_pcre_ucp_othercase(unicodeCurr + 1) == (otherCurr + 1))) { // increment unicodeCurr; it points to the end of the range. // increment otherCurr, due to the check above other for next must be 1 greater than the currrent other value. ++unicodeCurr; ++otherCurr; } // otherChar is the last in the range of other case chars, calculate offset to get back to the start. addSortedRange(m_rangesUnicode, otherCurr-(unicodeCurr-rangeStart), otherCurr); // unicodeCurr has been added, move on to the next char. ++unicodeCurr; } } } } else if (ch == '-') // EXAMPLE: parsing [-a-c], the second '-' reaches this case - the hyphen is treated as potentially indicating a range. m_isPendingDash = true; else { // EXAMPLE: Parsing [-a-c], the 'a' reaches this case - we repace the previously buffered char with the 'a'. flush(); m_charBuffer = ch; } } else // EXAMPLE: Parsing [-a-c], the first hyphen reaches this case - there is no buffered character // (the hyphen not treated as a special character in this case, same handling for any char). m_charBuffer = ch; } // When a character is added to the set we do not immediately add it to the arrays, in case it is actually defining a range. // When we have determined the character is not used in specifing a range it is added, in a sorted fashion, to the appropriate // array (either ascii or unicode). // If the pattern is case insensitive we add entries for both cases. void CharacterClassConstructor::flush() { if (m_charBuffer != -1) { if (m_charBuffer <= 0x7f) { if (m_isCaseInsensitive && isASCIILower(m_charBuffer)) addSorted(m_matches, toASCIIUpper(m_charBuffer)); addSorted(m_matches, m_charBuffer); if (m_isCaseInsensitive && isASCIIUpper(m_charBuffer)) addSorted(m_matches, toASCIILower(m_charBuffer)); } else { addSorted(m_matchesUnicode, m_charBuffer); if (m_isCaseInsensitive) { int other = jsc_pcre_ucp_othercase(m_charBuffer); if (other != -1) addSorted(m_matchesUnicode, other); } } m_charBuffer = -1; } if (m_isPendingDash) { addSorted(m_matches, '-'); m_isPendingDash = false; } } void CharacterClassConstructor::append(const CharacterClass& other) { // [x-\s] will add, 'x', '-', and all unicode spaces to new class (same as [x\s-]). // Need to check the spec, really, but think this matches PCRE behaviour. flush(); if (other.numMatches) { for (size_t i = 0; i < other.numMatches; ++i) addSorted(m_matches, other.matches[i]); } if (other.numRanges) { for (size_t i = 0; i < other.numRanges; ++i) addSortedRange(m_ranges, other.ranges[i].begin, other.ranges[i].end); } if (other.numMatchesUnicode) { for (size_t i = 0; i < other.numMatchesUnicode; ++i) addSorted(m_matchesUnicode, other.matchesUnicode[i]); } if (other.numRangesUnicode) { for (size_t i = 0; i < other.numRangesUnicode; ++i) addSortedRange(m_rangesUnicode, other.rangesUnicode[i].begin, other.rangesUnicode[i].end); } } } } // namespace JSC::WREC #endif // ENABLE(WREC)