static inline PRUint32
HexDigitValue(PRInt32 ch)
{
if (IsDigit(ch)) {
return DecimalDigitValue(ch);
} else {
// Note: c&7 just keeps the low three bits which causes
// upper and lower case alphabetics to both yield their
// "relative to 10" value for computing the hex value.
return (ch & 0x7) + 9;
}
}
PRBool
nsCSSScanner::ParseNumber(PRInt32 c, nsCSSToken& aToken)
{
NS_PRECONDITION(c == '.' || c == '+' || c == '-' || IsDigit(c),
"Why did we get called?");
aToken.mHasSign = (c == '+' || c == '-');
// Our sign.
PRInt32 sign = c == '-' ? -1 : 1;
// Absolute value of the integer part of the mantissa. This is a double so
// we don't run into overflow issues for consumers that only care about our
// floating-point value while still being able to express the full PRInt32
// range for consumers who want integers.
double intPart = 0;
// Fractional part of the mantissa. This is a double so that when we convert
// to float at the end we'll end up rounding to nearest float instead of
// truncating down (as we would if fracPart were a float and we just
// effectively lost the last several digits).
double fracPart = 0;
// Absolute value of the power of 10 that we should multiply by (only
// relevant for numbers in scientific notation). Has to be a signed integer,
// because multiplication of signed by unsigned converts the unsigned to
// signed, so if we plan to actually multiply by expSign...
PRInt32 exponent = 0;
// Sign of the exponent.
PRInt32 expSign = 1;
if (aToken.mHasSign) {
NS_ASSERTION(c != '.', "How did that happen?");
c = Read();
}
PRBool gotDot = (c == '.');
if (!gotDot) {
// Parse the integer part of the mantisssa
NS_ASSERTION(IsDigit(c), "Why did we get called?");
do {
intPart = 10*intPart + DecimalDigitValue(c);
c = Read();
// The IsDigit check will do the right thing even if Read() returns < 0
} while (IsDigit(c));
gotDot = (c == '.') && IsDigit(Peek());
}
if (gotDot) {
// Parse the fractional part of the mantissa.
c = Read();
NS_ASSERTION(IsDigit(c), "How did we get here?");
// Power of ten by which we need to divide our next digit
float divisor = 10;
do {
fracPart += DecimalDigitValue(c) / divisor;
divisor *= 10;
c = Read();
// The IsDigit check will do the right thing even if Read() returns < 0
} while (IsDigit(c));
}
PRBool gotE = PR_FALSE;
if (IsSVGMode() && (c == 'e' || c == 'E')) {
PRInt32 nextChar = Peek();
PRInt32 expSignChar = 0;
if (nextChar == '-' || nextChar == '+') {
expSignChar = Read();
nextChar = Peek();
}
if (IsDigit(nextChar)) {
gotE = PR_TRUE;
if (expSignChar == '-') {
expSign = -1;
}
c = Read();
NS_ASSERTION(IsDigit(c), "Peek() must have lied");
do {
exponent = 10*exponent + DecimalDigitValue(c);
c = Read();
// The IsDigit check will do the right thing even if Read() returns < 0
} while (IsDigit(c));
} else {
if (expSignChar) {
Pushback(expSignChar);
}
}
}
nsCSSTokenType type = eCSSToken_Number;
// Set mIntegerValid for all cases (except %, below) because we need
// it for the "2n" in :nth-child(2n).
aToken.mIntegerValid = PR_FALSE;
// Time to reassemble our number.
float value = float(sign * (intPart + fracPart));
if (gotE) {
// pow(), not powf(), because at least wince doesn't have the latter.
// And explicitly cast everything to doubles to avoid issues with
// overloaded pow() on Windows.
value *= pow(10.0, double(expSign * exponent));
} else if (!gotDot) {
// Clamp values outside of integer range.
if (sign > 0) {
aToken.mInteger = PRInt32(NS_MIN(intPart, double(PR_INT32_MAX)));
} else {
aToken.mInteger = PRInt32(NS_MAX(-intPart, double(PR_INT32_MIN)));
}
aToken.mIntegerValid = PR_TRUE;
}
nsString& ident = aToken.mIdent;
ident.Truncate();
// Look at character that terminated the number
if (c >= 0) {
if (StartsIdent(c, Peek())) {
if (!GatherIdent(c, ident)) {
return PR_FALSE;
}
type = eCSSToken_Dimension;
} else if ('%' == c) {
type = eCSSToken_Percentage;
value = value / 100.0f;
aToken.mIntegerValid = PR_FALSE;
} else {
// Put back character that stopped numeric scan
Pushback(c);
}
}
aToken.mNumber = value;
aToken.mType = type;
return PR_TRUE;
}
/**
* Scan a Number, Percentage, or Dimension token (all of which begin
* like a Number). Can produce a Symbol when a '.' is not followed by
* digits, or when '+' or '-' are not followed by either a digit or a
* '.' and then a digit. Can also produce a HTMLComment when it
* encounters '-->'.
*/
bool
nsCSSScanner::ScanNumber(nsCSSToken& aToken)
{
int32_t c = Peek();
#ifdef DEBUG
{
int32_t c2 = Peek(1);
int32_t c3 = Peek(2);
MOZ_ASSERT(IsDigit(c) ||
(IsDigit(c2) && (c == '.' || c == '+' || c == '-')) ||
(IsDigit(c3) && (c == '+' || c == '-') && c2 == '.'),
"should not have been called");
}
#endif
// Sign of the mantissa (-1 or 1).
int32_t sign = c == '-' ? -1 : 1;
// Absolute value of the integer part of the mantissa. This is a double so
// we don't run into overflow issues for consumers that only care about our
// floating-point value while still being able to express the full int32_t
// range for consumers who want integers.
double intPart = 0;
// Fractional part of the mantissa. This is a double so that when we convert
// to float at the end we'll end up rounding to nearest float instead of
// truncating down (as we would if fracPart were a float and we just
// effectively lost the last several digits).
double fracPart = 0;
// Absolute value of the power of 10 that we should multiply by (only
// relevant for numbers in scientific notation). Has to be a signed integer,
// because multiplication of signed by unsigned converts the unsigned to
// signed, so if we plan to actually multiply by expSign...
int32_t exponent = 0;
// Sign of the exponent.
int32_t expSign = 1;
aToken.mHasSign = (c == '+' || c == '-');
if (aToken.mHasSign) {
Advance();
c = Peek();
}
bool gotDot = (c == '.');
if (!gotDot) {
// Scan the integer part of the mantissa.
MOZ_ASSERT(IsDigit(c), "should have been excluded by logic above");
do {
intPart = 10*intPart + DecimalDigitValue(c);
Advance();
c = Peek();
} while (IsDigit(c));
gotDot = (c == '.') && IsDigit(Peek(1));
}
if (gotDot) {
// Scan the fractional part of the mantissa.
Advance();
c = Peek();
MOZ_ASSERT(IsDigit(c), "should have been excluded by logic above");
// Power of ten by which we need to divide our next digit
double divisor = 10;
do {
fracPart += DecimalDigitValue(c) / divisor;
divisor *= 10;
Advance();
c = Peek();
} while (IsDigit(c));
}
bool gotE = false;
if (c == 'e' || c == 'E') {
int32_t expSignChar = Peek(1);
int32_t nextChar = Peek(2);
if (IsDigit(expSignChar) ||
((expSignChar == '-' || expSignChar == '+') && IsDigit(nextChar))) {
gotE = true;
if (expSignChar == '-') {
expSign = -1;
}
Advance(); // consumes the E
if (expSignChar == '-' || expSignChar == '+') {
Advance();
c = nextChar;
} else {
c = expSignChar;
}
MOZ_ASSERT(IsDigit(c), "should have been excluded by logic above");
do {
exponent = 10*exponent + DecimalDigitValue(c);
Advance();
c = Peek();
} while (IsDigit(c));
}
}
nsCSSTokenType type = eCSSToken_Number;
// Set mIntegerValid for all cases (except %, below) because we need
// it for the "2n" in :nth-child(2n).
aToken.mIntegerValid = false;
// Time to reassemble our number.
// Do all the math in double precision so it's truncated only once.
double value = sign * (intPart + fracPart);
if (gotE) {
// Explicitly cast expSign*exponent to double to avoid issues with
// overloaded pow() on Windows.
value *= pow(10.0, double(expSign * exponent));
} else if (!gotDot) {
// Clamp values outside of integer range.
if (sign > 0) {
aToken.mInteger = int32_t(std::min(intPart, double(INT32_MAX)));
} else {
aToken.mInteger = int32_t(std::max(-intPart, double(INT32_MIN)));
}
aToken.mIntegerValid = true;
}
nsString& ident = aToken.mIdent;
// Check for Dimension and Percentage tokens.
if (c >= 0) {
if (StartsIdent(c, Peek(1))) {
if (GatherText(IS_IDCHAR, ident)) {
type = eCSSToken_Dimension;
}
} else if (c == '%') {
Advance();
type = eCSSToken_Percentage;
value = value / 100.0f;
aToken.mIntegerValid = false;
}
}
aToken.mNumber = value;
aToken.mType = type;
return true;
}
