/*
* Copyright (C) 2013, Opera Software ASA. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
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* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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*/
#include "config.h"
#include "BufferedLineReader.h"
#include "wtf/unicode/CharacterNames.h"
namespace WebCore {
bool BufferedLineReader::getLine(String& line)
{
if (m_maybeSkipLF) {
// We ran out of data after a CR (U+000D), which means that we may be
// in the middle of a CRLF pair. If the next character is a LF (U+000A)
// then skip it, and then (unconditionally) return the buffered line.
if (!m_buffer.isEmpty()) {
scanCharacter(newlineCharacter);
m_maybeSkipLF = false;
}
// If there was no (new) data available, then keep m_maybeSkipLF set,
// and fall through all the way down to the EOS check at the end of
// the method.
}
bool shouldReturnLine = false;
bool checkForLF = false;
while (!m_buffer.isEmpty()) {
UChar c = m_buffer.currentChar();
m_buffer.advance();
if (c == newlineCharacter || c == carriageReturn) {
// We found a line ending. Return the accumulated line.
shouldReturnLine = true;
checkForLF = (c == carriageReturn);
break;
}
// NULs are transformed into U+FFFD (REPLACEMENT CHAR.) in step 1 of
// the WebVTT parser algorithm.
if (c == '\0')
c = replacementCharacter;
m_lineBuffer.append(c);
}
if (checkForLF) {
// May be in the middle of a CRLF pair.
if (!m_buffer.isEmpty()) {
// Scan a potential newline character.
scanCharacter(newlineCharacter);
} else {
// Check for the LF on the next call (unless we reached EOS, in
// which case we'll return the contents of the line buffer, and
// reset state for the next line.)
m_maybeSkipLF = true;
}
}
if (isAtEndOfStream()) {
// We've reached the end of the stream proper. Emit a line if the
// current line buffer is non-empty. (Note that if shouldReturnLine is
// set already, we want to return a line nonetheless.)
shouldReturnLine |= !m_lineBuffer.isEmpty();
}
if (shouldReturnLine) {
line = m_lineBuffer.toString();
m_lineBuffer.clear();
return true;
}
ASSERT(m_buffer.isEmpty());
return false;
}
} // namespace WebCore