Fix the wavedecoder a little.

Handle RIFX and corrupted files better.  Update the autotest so that it
is run properly (and copies files properly in shadow build).  Fix the
gendata script to properly create testdata.

Change-Id: I47b705507bebaef54df2835ec767c6b220c64678
Reviewed-on: http://codereview.qt-project.org/6380
Sanity-Review: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: derick hawcroft <derick.hawcroft@nokia.com>

2 files changed, 102 insertions, 30 deletions

diff --git a/src/multimedia/effects/qwavedecoder_p.cpp b/src/multimedia/effects/qwavedecoder_p.cpp
index e173aed8d..ad4ecf26b 100644
--- a/src/multimedia/effects/qwavedecoder_p.cpp
+++ b/src/multimedia/effects/qwavedecoder_p.cpp
@@ -50,9 +50,10 @@ QWaveDecoder::QWaveDecoder(QIODevice *s, QObject *parent):
     QIODevice(parent),
     haveFormat(false),
     dataSize(0),
-    remaining(0),
     source(s),
-    state(QWaveDecoder::InitialState)
+    state(QWaveDecoder::InitialState),
+    junkToSkip(0),
+    bigEndian(false)
 {
     open(QIODevice::ReadOnly | QIODevice::Unbuffered);
 
@@ -106,7 +107,15 @@ qint64 QWaveDecoder::writeData(const char *data, qint64 len)
 
 void QWaveDecoder::handleData()
 {
-    bool valid = true;
+    // 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)
+            return;
+    }
+
     if (state == QWaveDecoder::InitialState) {
         if (source->bytesAvailable() < qint64(sizeof(RIFFHeader)))
             return;
@@ -114,7 +123,8 @@ void QWaveDecoder::handleData()
         RIFFHeader riff;
         source->read(reinterpret_cast<char *>(&riff), sizeof(RIFFHeader));
 
-        if (qstrncmp(riff.descriptor.id, "RIFF", 4) != 0 ||
+        // 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) {
             source->disconnect(SIGNAL(readyRead()), this, SLOT(handleData()));
             emit invalidFormat();
@@ -122,13 +132,17 @@ void QWaveDecoder::handleData()
             return;
         } else {
             state = QWaveDecoder::WaitingForFormatState;
+            if (qstrncmp(riff.descriptor.id, "RIFX", 4) == 0)
+                bigEndian = true;
+            else
+                bigEndian = false;
         }
     }
 
     if (state == QWaveDecoder::WaitingForFormatState) {
-        if (valid = findChunk("fmt ")) {
+        if (findChunk("fmt ")) {
             chunk descriptor;
-            source->peek(reinterpret_cast<char *>(&descriptor), sizeof(chunk));
+            peekChunk(&descriptor);
 
             if (source->bytesAvailable() < qint64(descriptor.size + sizeof(chunk)))
                 return;
@@ -138,20 +152,38 @@ void QWaveDecoder::handleData()
             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.
                 source->disconnect(SIGNAL(readyRead()), this, SLOT(handleData()));
                 emit invalidFormat();
 
                 return;
             } else {
-                int bps = qFromLittleEndian<quint16>(wave.bitsPerSample);
-
                 format.setCodec(QLatin1String("audio/pcm"));
-                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));
+
+                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;
             }
@@ -159,11 +191,14 @@ void QWaveDecoder::handleData()
     }
 
     if (state == QWaveDecoder::WaitingForDataState) {
-        if (valid = findChunk("data")) {
+        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;
@@ -174,22 +209,24 @@ void QWaveDecoder::handleData()
         }
     }
 
-    if (source->atEnd() || !valid) {
+    if (source->atEnd()) {
         source->disconnect(SIGNAL(readyRead()), this, SLOT(handleData()));
         emit invalidFormat();
 
         return;
     }
-
 }
 
 bool QWaveDecoder::enoughDataAvailable()
 {
-    if (source->bytesAvailable() < qint64(sizeof(chunk)))
+    chunk descriptor;
+    if (!peekChunk(&descriptor))
         return false;
 
-    chunk descriptor;
-    source->peek(reinterpret_cast<char *>(&descriptor), sizeof(chunk));
+    // 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;
@@ -199,19 +236,28 @@ bool QWaveDecoder::enoughDataAvailable()
 
 bool QWaveDecoder::findChunk(const char *chunkId)
 {
-    if (source->bytesAvailable() < qint64(sizeof(chunk)))
-        return false;
-
     chunk descriptor;
-    source->peek(reinterpret_cast<char *>(&descriptor), sizeof(chunk));
+    if (!peekChunk(&descriptor))
+        return false;
 
     if (qstrncmp(descriptor.id, chunkId, 4) == 0)
         return true;
 
-    while (source->bytesAvailable() >= qint64(sizeof(chunk) + descriptor.size)) {
-        discardBytes(sizeof(chunk) + descriptor.size);
+    // 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);
 
-        source->peek(reinterpret_cast<char *>(&descriptor), sizeof(chunk));
+        // 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;
@@ -220,12 +266,35 @@ bool QWaveDecoder::findChunk(const char *chunkId)
     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)
 {
-    if (source->isSequential())
-        source->read(numBytes);
-    else
+    // 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(numBytes); // uggh, wasted memory
+        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
diff --git a/src/multimedia/effects/qwavedecoder_p.h b/src/multimedia/effects/qwavedecoder_p.h
index 6c4c00c25..0d26fec4b 100644
--- a/src/multimedia/effects/qwavedecoder_p.h
+++ b/src/multimedia/effects/qwavedecoder_p.h
@@ -106,6 +106,8 @@ private:
         char        id[4];
         quint32     size;
     };
+    bool peekChunk(chunk* pChunk);
+
     struct RIFFHeader
     {
         chunk       descriptor;
@@ -124,10 +126,11 @@ private:
 
     bool haveFormat;
     qint64 dataSize;
-    qint64 remaining;
     QAudioFormat format;
     QIODevice *source;
     State state;
+    quint32 junkToSkip;
+    bool bigEndian;
 };
 
 QT_END_NAMESPACE