/**
* Skip over one CSS comment starting at the current read position.
*/
void
nsCSSScanner::SkipComment()
{
MOZ_ASSERT(Peek() == '/' && Peek(1) == '*', "should not have been called");
Advance(2);
for (;;) {
int32_t ch = Peek();
if (ch < 0) {
if (mReporter)
mReporter->ReportUnexpectedEOF("PECommentEOF");
SetEOFCharacters(eEOFCharacters_Asterisk | eEOFCharacters_Slash);
return;
}
if (ch == '*') {
Advance();
ch = Peek();
if (ch < 0) {
if (mReporter)
mReporter->ReportUnexpectedEOF("PECommentEOF");
SetEOFCharacters(eEOFCharacters_Slash);
return;
}
if (ch == '/') {
Advance();
return;
}
} else if (IsVertSpace(ch)) {
AdvanceLine();
} else {
Advance();
}
}
}
/**
* Skip over a sequence of whitespace characters (vertical or
* horizontal) starting at the current read position.
*/
void
nsCSSScanner::SkipWhitespace()
{
for (;;) {
int32_t ch = Peek();
if (!IsWhitespace(ch)) { // EOF counts as non-whitespace
break;
}
if (IsVertSpace(ch)) {
AdvanceLine();
} else {
Advance();
}
}
}
void Render() {
if (!mLine) {
return;
}
// Update elapsed time
mElapsedTime = timeGetTime() - mMovieStarted;
// Update current line
AdvanceLine();
// Should we display the current line?
if (IsCurrentLineVisible()) {
RenderCurrentLine();
}
}
/**
* If there is a valid escape sequence starting at the current read
* position, consume it, decode it, append the result to |aOutput|,
* and return true. Otherwise, consume nothing, leave |aOutput|
* unmodified, and return false. If |aInString| is true, accept the
* additional form of escape sequence allowed within string-like tokens.
*/
bool
nsCSSScanner::GatherEscape(nsString& aOutput, bool aInString)
{
MOZ_ASSERT(Peek() == '\\', "should not have been called");
int32_t ch = Peek(1);
if (ch < 0) {
// If we are in a string (or a url() containing a string), we want to drop
// the backslash on the floor. Otherwise, we want to treat it as a U+FFFD
// character.
Advance();
if (aInString) {
SetEOFCharacters(eEOFCharacters_DropBackslash);
} else {
aOutput.Append(UCS2_REPLACEMENT_CHAR);
SetEOFCharacters(eEOFCharacters_ReplacementChar);
}
return true;
}
if (IsVertSpace(ch)) {
if (aInString) {
// In strings (and in url() containing a string), escaped
// newlines are completely removed, to allow splitting over
// multiple lines.
Advance();
AdvanceLine();
return true;
}
// Outside of strings, backslash followed by a newline is not an escape.
return false;
}
if (!IsHexDigit(ch)) {
// "Any character (except a hexadecimal digit, linefeed, carriage
// return, or form feed) can be escaped with a backslash to remove
// its special meaning." -- CSS2.1 section 4.1.3
Advance(2);
if (ch == 0) {
aOutput.Append(UCS2_REPLACEMENT_CHAR);
} else {
aOutput.Append(ch);
}
return true;
}
// "[at most six hexadecimal digits following a backslash] stand
// for the ISO 10646 character with that number, which must not be
// zero. (It is undefined in CSS 2.1 what happens if a style sheet
// does contain a character with Unicode codepoint zero.)"
// -- CSS2.1 section 4.1.3
// At this point we know we have \ followed by at least one
// hexadecimal digit, therefore the escape sequence is valid and we
// can go ahead and consume the backslash.
Advance();
uint32_t val = 0;
int i = 0;
do {
val = val * 16 + HexDigitValue(ch);
i++;
Advance();
ch = Peek();
} while (i < 6 && IsHexDigit(ch));
// "Interpret the hex digits as a hexadecimal number. If this number is zero,
// or is greater than the maximum allowed codepoint, return U+FFFD
// REPLACEMENT CHARACTER" -- CSS Syntax Level 3
if (MOZ_UNLIKELY(val == 0)) {
aOutput.Append(UCS2_REPLACEMENT_CHAR);
} else {
AppendUCS4ToUTF16(ENSURE_VALID_CHAR(val), aOutput);
}
// Consume exactly one whitespace character after a
// hexadecimal escape sequence.
if (IsVertSpace(ch)) {
AdvanceLine();
} else if (IsHorzSpace(ch)) {
Advance();
}
return true;
}
