MythPlayer: Add support for InteractiveTV streams

This patch adds functionality to MythPlayer to enable interactive TV content
to select altenative streamed media for display.

NB this patch needs to be applied together with that for InteractionChannel
streaming.

Refs #10019

Signed-off-by: Lawrence Rust <lvr@softsystem.co.uk>
Signed-off-by: Stuart Morgan <smorgan@mythtv.org>

mythtv/libs/libmythtv/avformatdecoder.cpp

@@ -2203,6 +2203,9 @@ int AvFormatDecoder::ScanStreams(bool novideo)
         }
     }
 
+    if ((uint)ic->bit_rate > bitrate)
+        bitrate = (uint)ic->bit_rate;
+
     if (bitrate > 0)
     {
         bitrate = (bitrate + 999) / 1000;

mythtv/libs/libmythtv/icringbuffer.cpp

@@ -0,0 +1,172 @@
+#include "icringbuffer.h"
+
+#include <stdio.h> // SEEK_SET
+
+#include <QScopedPointer>
+#include <QWriteLocker>
+
+#include "netstream.h"
+#include "mythlogging.h"
+
+
+#define LOC QString("ICRingBuf ")
+
+
+ICRingBuffer::ICRingBuffer(const QString &url, RingBuffer *parent)
+  : RingBuffer(kRingBufferType), m_stream(0), m_parent(parent)
+{
+    startreadahead = true;
+    OpenFile(url);
+}
+
+ICRingBuffer::~ICRingBuffer()
+{
+    delete m_stream;
+    delete m_parent;
+}
+
+bool ICRingBuffer::IsOpen(void) const
+{
+    return m_stream ? m_stream->IsOpen() : false;
+}
+
+bool ICRingBuffer::OpenFile(const QString &url, uint retry_ms)
+{
+    if (!NetStream::IsSupported(url))
+    {
+        LOG(VB_GENERAL, LOG_ERR, LOC + QString("Unsupported URL %1").arg(url) );
+        return false;
+    }
+
+    QScopedPointer<NetStream> stream(new NetStream(url, NetStream::kNeverCache));
+    if (!stream || !stream->IsOpen())
+    {
+        LOG(VB_GENERAL, LOG_ERR, LOC + QString("Failed to open %1").arg(url) );
+        return false;
+    }
+
+    if (!stream->WaitTillReady(30000))
+    {
+        LOG(VB_GENERAL, LOG_ERR, LOC + QString("Stream not ready%1").arg(url) );
+        return false;
+    }
+
+    if (m_parent)
+        m_parent->Pause();
+
+    QWriteLocker locker(&rwlock);
+
+    safefilename = url;
+    filename = url;
+
+    delete m_stream;
+    m_stream = stream.take();
+
+    // The initial bitrate needs to be set with consideration for low bit rate
+    // streams (e.g. radio @ 64Kbps) such that fill_min bytes are received
+    // in a reasonable time period to enable decoders to peek the first few KB
+    // to determine type & settings.
+    rawbitrate = 128; // remotefile
+    CalcReadAheadThresh();
+
+    locker.unlock();
+    Reset(true, false, true);
+
+    LOG(VB_GENERAL, LOG_INFO, LOC + QString("Opened %1").arg(url));
+    return true;
+}
+
+long long ICRingBuffer::GetReadPosition(void) const
+{
+    return m_stream ? m_stream->GetReadPosition() : 0;
+}
+
+long long ICRingBuffer::Seek(long long pos, int whence, bool has_lock)
+{
+    if (!m_stream)
+        return -1;
+
+    // lockForWrite takes priority over lockForRead, so this will
+    // take priority over the lockForRead in the read ahead thread.
+    if (!has_lock)
+        rwlock.lockForWrite();
+
+    poslock.lockForWrite();
+
+    long long ret;
+
+    // Optimize no-op seeks
+    if (readaheadrunning &&
+        ((whence == SEEK_SET && pos == readpos) ||
+         (whence == SEEK_CUR && pos == 0)))
+    {
+        ret = readpos;
+
+        poslock.unlock();
+        if (!has_lock)
+            rwlock.unlock();
+
+        return ret;
+    }
+
+    switch (whence)
+    {
+        case SEEK_SET:
+            break;
+        case SEEK_CUR:
+            pos += m_stream->GetReadPosition();
+            break;
+        case SEEK_END:
+            pos += m_stream->GetSize();
+            break;
+        default:
+            errno = EINVAL;
+            ret = -1;
+            goto err;
+    }
+
+    ret = m_stream->Seek(pos);
+    if (ret >= 0)
+    {
+        readpos = ret;
+
+        ignorereadpos = -1;
+
+        if (readaheadrunning)
+            ResetReadAhead(readpos);
+
+        readAdjust = 0;
+    }
+
+err:
+    poslock.unlock();
+
+    generalWait.wakeAll();
+
+    if (!has_lock)
+        rwlock.unlock();
+
+    return ret;
+}
+
+int ICRingBuffer::safe_read(void *data, uint sz)
+{
+    return m_stream ? m_stream->safe_read(data, sz, 1000) : (ateof = true, 0);
+}
+
+long long ICRingBuffer::GetRealFileSize(void) const
+{
+    return m_stream ? m_stream->GetSize() : -1;
+}
+
+// Take ownership of parent RingBuffer
+RingBuffer *ICRingBuffer::Take()
+{
+    RingBuffer *parent = m_parent;
+    if (parent && IsOpen())
+        parent->Unpause();
+    m_parent = 0;
+    return parent;
+}
+
+// End of file

mythtv/libs/libmythtv/icringbuffer.h

@@ -0,0 +1,40 @@
+#ifndef ICRINGBUFFER_H
+#define ICRINGBUFFER_H
+
+#include "ringbuffer.h"
+
+class NetStream;
+
+class ICRingBuffer : public RingBuffer
+{
+  public:
+    static enum RingBufferType const kRingBufferType = kRingBuffer_MHEG;
+
+    ICRingBuffer(const QString &url, RingBuffer *parent = 0);
+    virtual ~ICRingBuffer();
+
+    // RingBuffer implementation
+    virtual bool IsOpen(void) const;
+    virtual long long GetReadPosition(void) const;
+    virtual bool OpenFile(const QString &url,
+                          uint retry_ms = kDefaultOpenTimeout);
+    virtual long long Seek(long long pos, int whence, bool has_lock);
+    virtual long long GetRealFileSize(void) const;
+    virtual bool IsStreamed(void)       { return false;  }
+    virtual bool IsSeekingAllowed(void) { return true; }
+    virtual bool IsBookmarkAllowed(void) { return false; }
+
+  protected:
+    virtual int safe_read(void *data, uint sz);
+
+    // Operations
+  public:
+    // Take ownership of parent RingBuffer
+    RingBuffer *Take();
+
+  private:
+    NetStream *m_stream;
+    RingBuffer *m_parent; // parent RingBuffer
+};
+
+#endif // ICRINGBUFFER_H

mythtv/libs/libmythtv/libmythtv.pro

@@ -123,6 +123,7 @@ HEADERS += mythsystemevent.h
 HEADERS += avfringbuffer.h          ThreadedFileWriter.h
 HEADERS += ringbuffer.h             fileringbuffer.h
 HEADERS += streamingringbuffer.h    metadataimagehelper.h
+HEADERS += icringbuffer.h
 
 SOURCES += recordinginfo.cpp
 SOURCES += dbcheck.cpp
@@ -150,6 +151,7 @@ SOURCES += mythsystemevent.cpp
 SOURCES += avfringbuffer.cpp        ThreadedFileWriter.cpp
 SOURCES += ringbuffer.cpp           fileringBuffer.cpp
 SOURCES += streamingringbuffer.cpp  metadataimagehelper.cpp
+SOURCES += icringbuffer.cpp
 
 # DiSEqC
 HEADERS += diseqc.h                 diseqcsettings.h
@@ -420,6 +422,10 @@ using_frontend {
         SOURCES += dsmcc.cpp                dsmcccache.cpp
         SOURCES += dsmccbiop.cpp            dsmccobjcarousel.cpp
 
+         # MHEG interaction channel
+        HEADERS += netstream.h
+        SOURCES += netstream.cpp
+
         # MHEG/MHI stuff
         HEADERS += interactivetv.h          mhi.h
         SOURCES += interactivetv.cpp        mhi.cpp