bool parseAdditiveValueExpression(CSSParserValueList* tokens, int depth, unsigned* index, Value* result)
{
if (checkDepthAndIndex(&depth, *index, tokens) != OK)
return false;
if (!parseValueMultiplicativeExpression(tokens, depth, index, result))
return false;
while (*index < tokens->size() - 1) {
char operatorCharacter = operatorValue(tokens, *index);
if (operatorCharacter != CalcAdd && operatorCharacter != CalcSubtract)
break;
++*index;
Value rhs;
if (!parseValueMultiplicativeExpression(tokens, depth, index, &rhs))
return false;
result->value = CSSCalcBinaryOperation::create(result->value, rhs.value, static_cast<CalcOperator>(operatorCharacter));
if (!result->value)
return false;
}
ASSERT(*index <= tokens->size());
return true;
}
bool parseValueMultiplicativeExpression(CSSParserTokenRange& tokens, int depth, Value* result)
{
if (checkDepthAndIndex(&depth, tokens) != OK)
return false;
if (!parseValueTerm(tokens, depth, result))
return false;
while (!tokens.atEnd()) {
char operatorCharacter = operatorValue(tokens.peek());
if (operatorCharacter != CalcMultiply && operatorCharacter != CalcDivide)
break;
tokens.consumeIncludingWhitespace();
Value rhs;
if (!parseValueTerm(tokens, depth, &rhs))
return false;
result->value = CSSCalcBinaryOperation::createSimplified(result->value, rhs.value, static_cast<CalcOperator>(operatorCharacter));
if (!result->value)
return false;
}
return true;
}
bool parseAdditiveValueExpression(CSSParserTokenRange& tokens, int depth, Value* result)
{
if (checkDepthAndIndex(&depth, tokens) != OK)
return false;
if (!parseValueMultiplicativeExpression(tokens, depth, result))
return false;
while (!tokens.atEnd()) {
char operatorCharacter = operatorValue(tokens.peek());
if (operatorCharacter != CalcAdd && operatorCharacter != CalcSubtract)
break;
if ((&tokens.peek() - 1)->type() != WhitespaceToken)
return false; // calc(1px+ 2px) is invalid
tokens.consume();
if (tokens.peek().type() != WhitespaceToken)
return false; // calc(1px +2px) is invalid
tokens.consumeIncludingWhitespace();
Value rhs;
if (!parseValueMultiplicativeExpression(tokens, depth, &rhs))
return false;
result->value = CSSCalcBinaryOperation::createSimplified(result->value, rhs.value, static_cast<CalcOperator>(operatorCharacter));
if (!result->value)
return false;
}
return true;
}
bool parseValueTerm(CSSParserTokenRange& tokens, int depth, Value* result)
{
if (checkDepthAndIndex(&depth, tokens) != OK)
return false;
if (tokens.peek().type() == LeftParenthesisToken) {
CSSParserTokenRange innerRange = tokens.consumeBlock();
tokens.consumeWhitespace();
innerRange.consumeWhitespace();
return parseValueExpression(innerRange, depth, result);
}
return parseValue(tokens, result);
}
bool parseValueTerm(CSSParserValueList* tokens, int depth, unsigned* index, Value* result)
{
if (checkDepthAndIndex(&depth, *index, tokens) != OK)
return false;
if (operatorValue(tokens, *index) == '(') {
unsigned currentIndex = *index + 1;
if (!parseValueExpression(tokens, depth, ¤tIndex, result))
return false;
if (operatorValue(tokens, currentIndex) != ')')
return false;
*index = currentIndex + 1;
return true;
}
return parseValue(tokens, index, result);
}