Restructure the source code a little.

Change-Id: I995b0fb33bdda7f01bf6266c1c50a1b17eba6760
Reviewed-by: Jonas Rabbe <jonas.rabbe@nokia.com>

1 files changed, 307 insertions, 0 deletions

diff --git a/src/multimedia/audio/qwavedecoder_p.cpp b/src/multimedia/audio/qwavedecoder_p.cpp
new file mode 100644
index 000000000..eb65a3aca
--- /dev/null
+++ b/src/multimedia/audio/qwavedecoder_p.cpp
@@ -0,0 +1,307 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** GNU Lesser General Public License Usage
+** This file may be used under the terms of the GNU Lesser General Public
+** License version 2.1 as published by the Free Software Foundation and
+** appearing in the file LICENSE.LGPL included in the packaging of this
+** file. Please review the following information to ensure the GNU Lesser
+** General Public License version 2.1 requirements will be met:
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU General
+** Public License version 3.0 as published by the Free Software Foundation
+** and appearing in the file LICENSE.GPL included in the packaging of this
+** file. Please review the following information to ensure the GNU General
+** Public License version 3.0 requirements will be met:
+** http://www.gnu.org/copyleft/gpl.html.
+**
+** Other Usage
+** Alternatively, this file may be used in accordance with the terms and
+** conditions contained in a signed written agreement between you and Nokia.
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qwavedecoder_p.h"
+
+#include <QtCore/qtimer.h>
+#include <QtCore/qendian.h>
+
+QT_BEGIN_NAMESPACE
+
+QWaveDecoder::QWaveDecoder(QIODevice *s, QObject *parent):
+    QIODevice(parent),
+    haveFormat(false),
+    dataSize(0),
+    source(s),
+    state(QWaveDecoder::InitialState),
+    junkToSkip(0),
+    bigEndian(false)
+{
+    open(QIODevice::ReadOnly | QIODevice::Unbuffered);
+
+    if (enoughDataAvailable())
+        QTimer::singleShot(0, this, SLOT(handleData()));
+    else
+        connect(source, SIGNAL(readyRead()), SLOT(handleData()));
+}
+
+QWaveDecoder::~QWaveDecoder()
+{
+}
+
+QAudioFormat QWaveDecoder::audioFormat() const
+{
+    return format;
+}
+
+int QWaveDecoder::duration() const
+{
+    return size() * 1000 / (format.sampleSize() / 8) / format.channels() / format.frequency();
+}
+
+qint64 QWaveDecoder::size() const
+{
+    return haveFormat ? dataSize : 0;
+}
+
+bool QWaveDecoder::isSequential() const
+{
+    return source->isSequential();
+}
+
+qint64 QWaveDecoder::bytesAvailable() const
+{
+    return haveFormat ? source->bytesAvailable() : 0;
+}
+
+qint64 QWaveDecoder::readData(char *data, qint64 maxlen)
+{
+    return haveFormat ? source->read(data, maxlen) : 0;
+}
+
+qint64 QWaveDecoder::writeData(const char *data, qint64 len)
+{
+    Q_UNUSED(data);
+    Q_UNUSED(len);
+
+    return -1;
+}
+
+void QWaveDecoder::parsingFailed()
+{
+    Q_ASSERT(source);
+    source->disconnect(SIGNAL(readyRead()), this, SLOT(handleData()));
+    emit parsingError();
+}
+
+void QWaveDecoder::handleData()
+{
+    // As a special "state", if we have junk to skip, we do
+    if (junkToSkip > 0) {
+        discardBytes(junkToSkip); // this also updates junkToSkip
+
+        // If we couldn't skip all the junk, return
+        if (junkToSkip > 0) {
+            // We might have run out
+            if (source->atEnd())
+                parsingFailed();
+            return;
+        }
+    }
+
+    if (state == QWaveDecoder::InitialState) {
+        if (source->bytesAvailable() < qint64(sizeof(RIFFHeader)))
+            return;
+
+        RIFFHeader riff;
+        source->read(reinterpret_cast<char *>(&riff), sizeof(RIFFHeader));
+
+        // RIFF = little endian RIFF, RIFX = big endian RIFF
+        if (((qstrncmp(riff.descriptor.id, "RIFF", 4) != 0) && (qstrncmp(riff.descriptor.id, "RIFX", 4) != 0))
+                || qstrncmp(riff.type, "WAVE", 4) != 0) {
+            parsingFailed();
+            return;
+        } else {
+            state = QWaveDecoder::WaitingForFormatState;
+            if (qstrncmp(riff.descriptor.id, "RIFX", 4) == 0)
+                bigEndian = true;
+            else
+                bigEndian = false;
+        }
+    }
+
+    if (state == QWaveDecoder::WaitingForFormatState) {
+        if (findChunk("fmt ")) {
+            chunk descriptor;
+            peekChunk(&descriptor);
+
+            if (source->bytesAvailable() < qint64(descriptor.size + sizeof(chunk)))
+                return;
+
+            WAVEHeader wave;
+            source->read(reinterpret_cast<char *>(&wave), sizeof(WAVEHeader));
+            if (descriptor.size > sizeof(WAVEHeader))
+                discardBytes(descriptor.size - sizeof(WAVEHeader));
+
+            // Swizzle this
+            if (bigEndian) {
+                wave.audioFormat = qFromBigEndian<quint16>(wave.audioFormat);
+            }
+
+            if (wave.audioFormat != 0 && wave.audioFormat != 1) {
+                // 32bit wave files have format == 0xFFFE (WAVE_FORMAT_EXTENSIBLE).
+                // but don't support them at the moment.
+                parsingFailed();
+                return;
+            } else {
+                format.setCodec(QLatin1String("audio/pcm"));
+
+                if (bigEndian) {
+                    int bps = qFromBigEndian<quint16>(wave.bitsPerSample);
+
+                    format.setSampleType(bps == 8 ? QAudioFormat::UnSignedInt : QAudioFormat::SignedInt);
+                    format.setByteOrder(QAudioFormat::BigEndian);
+                    format.setFrequency(qFromBigEndian<quint32>(wave.sampleRate));
+                    format.setSampleSize(bps);
+                    format.setChannels(qFromBigEndian<quint16>(wave.numChannels));
+                } else {
+                    int bps = qFromLittleEndian<quint16>(wave.bitsPerSample);
+
+                    format.setSampleType(bps == 8 ? QAudioFormat::UnSignedInt : QAudioFormat::SignedInt);
+                    format.setByteOrder(QAudioFormat::LittleEndian);
+                    format.setFrequency(qFromLittleEndian<quint32>(wave.sampleRate));
+                    format.setSampleSize(bps);
+                    format.setChannels(qFromLittleEndian<quint16>(wave.numChannels));
+                }
+
+                state = QWaveDecoder::WaitingForDataState;
+            }
+        }
+    }
+
+    if (state == QWaveDecoder::WaitingForDataState) {
+        if (findChunk("data")) {
+            source->disconnect(SIGNAL(readyRead()), this, SLOT(handleData()));
+
+            chunk descriptor;
+            source->read(reinterpret_cast<char *>(&descriptor), sizeof(chunk));
+            if (bigEndian)
+                descriptor.size = qFromBigEndian<quint32>(descriptor.size);
+
+            dataSize = descriptor.size;
+
+            haveFormat = true;
+            connect(source, SIGNAL(readyRead()), SIGNAL(readyRead()));
+            emit formatKnown();
+
+            return;
+        }
+    }
+
+    // If we hit the end without finding data, it's a parsing error
+    if (source->atEnd()) {
+        parsingFailed();
+    }
+}
+
+bool QWaveDecoder::enoughDataAvailable()
+{
+    chunk descriptor;
+    if (!peekChunk(&descriptor))
+        return false;
+
+    // This is only called for the RIFF/RIFX header, before bigEndian is set,
+    // so we have to manually swizzle
+    if (qstrncmp(descriptor.id, "RIFX", 4) == 0)
+        descriptor.size = qFromBigEndian<quint32>(descriptor.size);
+
+    if (source->bytesAvailable() < qint64(sizeof(chunk) + descriptor.size))
+        return false;
+
+    return true;
+}
+
+bool QWaveDecoder::findChunk(const char *chunkId)
+{
+    chunk descriptor;
+    if (!peekChunk(&descriptor))
+        return false;
+
+    if (qstrncmp(descriptor.id, chunkId, 4) == 0)
+        return true;
+
+    // It's possible that bytes->available() is less than the chunk size
+    // if it's corrupt.
+    junkToSkip = qint64(sizeof(chunk) + descriptor.size);
+    while (source->bytesAvailable() > 0) {
+        // Skip the current amount
+        if (junkToSkip > 0)
+            discardBytes(junkToSkip);
+
+        // If we still have stuff left, just exit and try again later
+        // since we can't call peekChunk
+        if (junkToSkip > 0)
+            return false;
+
+        if (!peekChunk(&descriptor))
+            return false;
+
+        if (qstrncmp(descriptor.id, chunkId, 4) == 0)
+            return true;
+    }
+
+    return false;
+}
+
+// Handles endianness
+bool QWaveDecoder::peekChunk(chunk *pChunk)
+{
+    if (source->bytesAvailable() < qint64(sizeof(chunk)))
+        return false;
+
+    source->peek(reinterpret_cast<char *>(pChunk), sizeof(chunk));
+    if (bigEndian)
+        pChunk->size = qFromBigEndian<quint32>(pChunk->size);
+
+    return true;
+}
+
+void QWaveDecoder::discardBytes(qint64 numBytes)
+{
+    // Discards a number of bytes
+    // If the iodevice doesn't have this many bytes in it,
+    // remember how much more junk we have to skip.
+    if (source->isSequential()) {
+        QByteArray r = source->read(qMin(numBytes, qint64(16384))); // uggh, wasted memory, limit to a max of 16k
+        if (r.size() < numBytes)
+            junkToSkip = numBytes - r.size();
+        else
+            junkToSkip = 0;
+    } else {
+        quint64 origPos = source->pos();
+        source->seek(source->pos() + numBytes);
+        junkToSkip = origPos + numBytes - source->pos();
+    }
+}
+
+QT_END_NAMESPACE
+
+#include "moc_qwavedecoder_p.cpp"