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-rw-r--r--intl/icu/source/common/ruleiter.cpp162
1 files changed, 162 insertions, 0 deletions
diff --git a/intl/icu/source/common/ruleiter.cpp b/intl/icu/source/common/ruleiter.cpp
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+++ b/intl/icu/source/common/ruleiter.cpp
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+// Copyright (C) 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
+/*
+**********************************************************************
+* Copyright (c) 2003-2011, International Business Machines
+* Corporation and others. All Rights Reserved.
+**********************************************************************
+* Author: Alan Liu
+* Created: September 24 2003
+* Since: ICU 2.8
+**********************************************************************
+*/
+#include "ruleiter.h"
+#include "unicode/parsepos.h"
+#include "unicode/symtable.h"
+#include "unicode/unistr.h"
+#include "unicode/utf16.h"
+#include "patternprops.h"
+
+/* \U87654321 or \ud800\udc00 */
+#define MAX_U_NOTATION_LEN 12
+
+U_NAMESPACE_BEGIN
+
+RuleCharacterIterator::RuleCharacterIterator(const UnicodeString& theText, const SymbolTable* theSym,
+ ParsePosition& thePos) :
+ text(theText),
+ pos(thePos),
+ sym(theSym),
+ buf(0),
+ bufPos(0)
+{}
+
+UBool RuleCharacterIterator::atEnd() const {
+ return buf == 0 && pos.getIndex() == text.length();
+}
+
+UChar32 RuleCharacterIterator::next(int32_t options, UBool& isEscaped, UErrorCode& ec) {
+ if (U_FAILURE(ec)) return DONE;
+
+ UChar32 c = DONE;
+ isEscaped = FALSE;
+
+ for (;;) {
+ c = _current();
+ _advance(U16_LENGTH(c));
+
+ if (c == SymbolTable::SYMBOL_REF && buf == 0 &&
+ (options & PARSE_VARIABLES) != 0 && sym != 0) {
+ UnicodeString name = sym->parseReference(text, pos, text.length());
+ // If name is empty there was an isolated SYMBOL_REF;
+ // return it. Caller must be prepared for this.
+ if (name.length() == 0) {
+ break;
+ }
+ bufPos = 0;
+ buf = sym->lookup(name);
+ if (buf == 0) {
+ ec = U_UNDEFINED_VARIABLE;
+ return DONE;
+ }
+ // Handle empty variable value
+ if (buf->length() == 0) {
+ buf = 0;
+ }
+ continue;
+ }
+
+ if ((options & SKIP_WHITESPACE) != 0 && PatternProps::isWhiteSpace(c)) {
+ continue;
+ }
+
+ if (c == 0x5C /*'\\'*/ && (options & PARSE_ESCAPES) != 0) {
+ UnicodeString tempEscape;
+ int32_t offset = 0;
+ c = lookahead(tempEscape, MAX_U_NOTATION_LEN).unescapeAt(offset);
+ jumpahead(offset);
+ isEscaped = TRUE;
+ if (c < 0) {
+ ec = U_MALFORMED_UNICODE_ESCAPE;
+ return DONE;
+ }
+ }
+
+ break;
+ }
+
+ return c;
+}
+
+void RuleCharacterIterator::getPos(RuleCharacterIterator::Pos& p) const {
+ p.buf = buf;
+ p.pos = pos.getIndex();
+ p.bufPos = bufPos;
+}
+
+void RuleCharacterIterator::setPos(const RuleCharacterIterator::Pos& p) {
+ buf = p.buf;
+ pos.setIndex(p.pos);
+ bufPos = p.bufPos;
+}
+
+void RuleCharacterIterator::skipIgnored(int32_t options) {
+ if ((options & SKIP_WHITESPACE) != 0) {
+ for (;;) {
+ UChar32 a = _current();
+ if (!PatternProps::isWhiteSpace(a)) break;
+ _advance(U16_LENGTH(a));
+ }
+ }
+}
+
+UnicodeString& RuleCharacterIterator::lookahead(UnicodeString& result, int32_t maxLookAhead) const {
+ if (maxLookAhead < 0) {
+ maxLookAhead = 0x7FFFFFFF;
+ }
+ if (buf != 0) {
+ buf->extract(bufPos, maxLookAhead, result);
+ } else {
+ text.extract(pos.getIndex(), maxLookAhead, result);
+ }
+ return result;
+}
+
+void RuleCharacterIterator::jumpahead(int32_t count) {
+ _advance(count);
+}
+
+/*
+UnicodeString& RuleCharacterIterator::toString(UnicodeString& result) const {
+ int32_t b = pos.getIndex();
+ text.extract(0, b, result);
+ return result.append((UChar) 0x7C).append(text, b, 0x7FFFFFFF); // Insert '|' at index
+}
+*/
+
+UChar32 RuleCharacterIterator::_current() const {
+ if (buf != 0) {
+ return buf->char32At(bufPos);
+ } else {
+ int i = pos.getIndex();
+ return (i < text.length()) ? text.char32At(i) : (UChar32)DONE;
+ }
+}
+
+void RuleCharacterIterator::_advance(int32_t count) {
+ if (buf != 0) {
+ bufPos += count;
+ if (bufPos == buf->length()) {
+ buf = 0;
+ }
+ } else {
+ pos.setIndex(pos.getIndex() + count);
+ if (pos.getIndex() > text.length()) {
+ pos.setIndex(text.length());
+ }
+ }
+}
+
+U_NAMESPACE_END
+
+//eof