Defines a stream data source built on top of a Http Stream. More...

#include <StreamHttpDataSource.h>

Inheritance diagram for StreamHttpDataSource:

Collaboration diagram for StreamHttpDataSource:

Public Member Functions
Creators
	StreamHttpDataSource (Url url, int iFlags)
	Default constructor. More...

virtual	~StreamHttpDataSource ()
	Destructor. More...

Manipulators
virtual OsStatus	open ()
	Opens the data source. More...

virtual OsStatus	close ()
	Closes the data source. More...

virtual OsStatus	destroyAndDelete ()
	Destroys and deletes the data source object. More...

virtual OsStatus	read (char *szBuffer, int iLength, int &iLengthRead)

virtual OsStatus	peek (char *szBuffer, int iLength, int &iLengthRead)
	Identical to read, except the stream pointer is not advanced. More...

virtual OsStatus	interrupt ()
	Interrupts any time consuming operation. More...

virtual OsStatus	seek (unsigned int iLocation)
	Moves the stream pointer to the an absolute location. More...

UtlBoolean	deliverData (char *szData, int iLength, int iMaxLength)
	Callback routine that is invoked whenever new data is available from http socket. More...

Accessors
virtual OsStatus	getLength (int &iLength)
	Gets the length of the stream (if available) More...

virtual OsStatus	getPosition (int &iPosition)
	Gets the current position within the stream. More...

virtual OsStatus	toString (UtlString &string)
	Renders a string describing this data source. More...

virtual int	getBufferedLength ()
	Gets the amount of data presently buffered. More...

Public Member Functions inherited from StreamDataSource
	StreamDataSource (int iFlags=0)
	Constructors a StreamDataSource given optional flags. More...

virtual	~StreamDataSource ()
	Destructor. More...

void	setListener (StreamDataSourceListener *pListener)

int	getFlags ()
	Gets the flags specified at time of construction. More...

Protected Member Functions
	StreamHttpDataSource (const StreamHttpDataSource &rStreamHttpDataSource)
	Copy constructor (not supported) More...

StreamHttpDataSource &	operator= (const StreamHttpDataSource &rhs)
	Assignment operator (not supported) More...

int	run (void *pArgs)
	Thread entry point. More...

Protected Member Functions inherited from StreamDataSource
	StreamDataSource (const StreamDataSource &rStreamDataSource)
	Copy constructor (not supported) More...

StreamDataSource &	operator= (const StreamDataSource &rhs)
	Assignment operator (not supported) More...

void	fireEvent (StreamDataSourceEvent event)
	Fires a data source event to the interested consumer. More...

Private Attributes
Url	m_url
	Source url. More...

UtlString	mBuffer
	Buffered content. More...

OsBSem	mSemNeedData
	Used block when we need more data. More...

OsBSem	mSemLimitData
	Used to block when need to throttle. More...

OsBSem	mSemGuardData
	Protected data structures. More...

OsBSem	mSemGuardStartClose
	Protected Opening/Closing the DataSource. More...

UtlBoolean	mbDone
	Is the data source complete. More...

UtlBoolean	mbQuit
	Are we quiting? More...

UtlBoolean	mbDeleteOnCompletion
	Should the run method delete the object? More...

unsigned int	miMaxData
	Max amount of data to buffer. More...

unsigned int	miDSLength
	Data Stream Length. More...

unsigned int	miOffset
	Present offset into the buffer. More...

unsigned int	miBufferOffset
	Buffer offset from start of stream. More...

UtlBoolean	mbFiredThrottledEvent
	Should fire event on next throttle? More...

UtlBoolean	mbClosed
	Have we closed this down? More...

UtlBoolean	mbInterrupt
	Interrupt current operation? More...

Static Private Attributes
static OsBSem	sSemGuardDelete
	Guard deletion of data sources. More...

Detailed Description

Defines a stream data source built on top of a Http Stream.

Deletion of this class is very problematic, because the thread that pumps the data from the stream may be blocked for a long period of time and most cases the media task is player destroying this resource. Ideally, we would interrupt the socket read, however, that is not possible. So, to avoid blocking the thread context used to destroy this object, we use a variable mbDeleteOnCompletion to mark if/when we need to destroy this class once the run method has completed. This method is wrapped in a static binary semaphore to guard against races.

Constructor & Destructor Documentation

StreamHttpDataSource	(	Url	url,
		int	iFlags
	)

Default constructor.

~StreamHttpDataSource ( )

virtual

Destructor.

StreamHttpDataSource ( const StreamHttpDataSource & rStreamHttpDataSource )

protected

Copy constructor (not supported)

Member Function Documentation

OsStatus open ( )

virtual

Opens the data source.

Implements StreamDataSource.

OsStatus close ( )

virtual

Closes the data source.

Implements StreamDataSource.

OsStatus destroyAndDelete ( )

virtual

Destroys and deletes the data source object.

Implements StreamDataSource.

OsStatus read	(	char *	szBuffer,
		int	iLength,
		int &	iLengthRead
	)

virtual

Reads iLength bytes of data from the data source and places the data into the passed szBuffer buffer.

Parameters

szBuffer	- Buffer to place data
iLength	- Max length to read
iLengthRead	- The actual amount of data read.

Implements StreamDataSource.

OsStatus peek	(	char *	szBuffer,
		int	iLength,
		int &	iLengthRead
	)

virtual

Identical to read, except the stream pointer is not advanced.

Parameters

szBuffer	- Buffer to place data
iLength	- Max length to read
iLengthRead	- The actual amount of data read.

Implements StreamDataSource.

OsStatus interrupt ( )

virtual

Interrupts any time consuming operation.

For example, some data sources may require network access (e.g. http) to read or fetch data. Invoking an interrupt() will cause any time consuming or blocking calls to exit with more quickly with an OS_INTERRUPTED return code.

Reimplemented from StreamDataSource.

OsStatus seek ( unsigned int iLocation )

virtual

Moves the stream pointer to the an absolute location.

Parameters

iLocation - The desired seek location

Implements StreamDataSource.

UtlBoolean deliverData	(	char *	szData,
		int	iLength,
		int	iMaxLength
	)

Callback routine that is invoked whenever new data is available from http socket.

OsStatus getLength ( int & iLength )

virtual

Gets the length of the stream (if available)

Implements StreamDataSource.

OsStatus getPosition ( int & iPosition )

virtual

Gets the current position within the stream.

Implements StreamDataSource.

OsStatus toString ( UtlString & string )

virtual

Renders a string describing this data source.

Implements StreamDataSource.

int getBufferedLength ( )

virtual

Gets the amount of data presently buffered.

StreamHttpDataSource & operator= ( const StreamHttpDataSource & rhs )

protected

Assignment operator (not supported)

int run ( void * pArgs )

protected

Thread entry point.

Member Data Documentation

Url m_url

private

Source url.

UtlString mBuffer

private

Buffered content.

OsBSem mSemNeedData

private

Used block when we need more data.

OsBSem mSemLimitData

private

Used to block when need to throttle.

OsBSem mSemGuardData

private

Protected data structures.

OsBSem mSemGuardStartClose

private

Protected Opening/Closing the DataSource.

UtlBoolean mbDone

private

Is the data source complete.

UtlBoolean mbQuit

private

Are we quiting?

UtlBoolean mbDeleteOnCompletion

private

Should the run method delete the object?

unsigned int miMaxData

private

Max amount of data to buffer.

unsigned int miDSLength

private

Data Stream Length.

unsigned int miOffset

private

Present offset into the buffer.

unsigned int miBufferOffset

private

Buffer offset from start of stream.

UtlBoolean mbFiredThrottledEvent

private

Should fire event on next throttle?

UtlBoolean mbClosed

private

Have we closed this down?

UtlBoolean mbInterrupt

private

Interrupt current operation?

OsBSem sSemGuardDelete

staticprivate

Guard deletion of data sources.

Public Member Functions

Protected Member Functions

Private Attributes

Static Private Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation