blob: 667795efabcf39632c79a8c2480a8656099bce02 [file] [log] [blame]
/*
**********************************************************************
* 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