The Nebula Device 3: IO::ZipFileStream Class Reference

The Nebula Device 3

IO::ZipFileStream Class Reference

#include <zipfilestream.h>

Inheritance diagram for IO::ZipFileStream:

IO::Stream Core::RefCounted


Detailed Description

Wraps a file in a zip archive into a stream. Allows random access to the file by caching the entire file contents into RAM (the zip filesystem doesn't allow seeking in files). Also note that ZipFileStreams are read-only.

The IO::Server allows transparent access to data in zip files through normal "file:" URIs by first checking whether the file is part of a mounted zip archive. Only if this is not the case, the file will be opened as normal.

To force reading from a zip archive, use an URI of the following format:

zip://[samba server]/bla/blob/archive.zip?file=path/in/zipfile&pwd=password

This assumes that the URI scheme "zip" has been associated with the ZipFileStream class using the IO::Server::RegisterUriScheme() method.

The server and local path part of the URI contain the path to the zip archive file. The query part contains the path of the file in the zip archive and an optional password.

(C) 2006 Radon Labs GmbH

Public Types

enum  AccessMode
 access modes
enum  AccessPattern
 access prefered pattern
enum  SeekOrigin
 seek origins
typedef int Position
 typedefs

Public Member Functions

 ZipFileStream ()
 constructor
virtual ~ZipFileStream ()
 destructor
virtual bool CanRead () const
 memory streams support reading
virtual bool CanWrite () const
 memory streams support writing
virtual bool CanSeek () const
 memory streams support seeking
virtual bool CanBeMapped () const
 memory streams are mappable
virtual Size GetSize () const
 get the size of the stream in bytes
virtual Position GetPosition () const
 get the current position of the read/write cursor
virtual bool Open ()
 open the stream
virtual void Close ()
 close the stream
virtual Size Read (void *ptr, Size numBytes)
 directly read from the stream
virtual void Seek (Offset offset, SeekOrigin origin)
 seek in stream
virtual bool Eof () const
 return true if end-of-stream reached
virtual void * Map ()
 map for direct memory-access
virtual void Unmap ()
 unmap a mapped stream
void SetURI (const URI &u)
 set stream location as URI
const URIGetURI () const
 get stream URI
virtual void SetSize (Size s)
 set a new size for the stream
void SetAccessMode (AccessMode m)
 set the access mode of the stream (default is ReadAccess)
AccessMode GetAccessMode () const
 get the access mode of the stream
void SetAccessPattern (AccessPattern p)
 set the prefered access pattern (default is Sequential)
AccessPattern GetAccessPattern () const
 get the prefered access pattern
void SetMediaType (const MediaType &t)
 set optional media type of stream content
const MediaTypeGetMediaType () const
 get optional media type
bool IsOpen () const
 return true if currently open
virtual void Write (const void *ptr, Size numBytes)
 directly write to the stream
virtual Size Read (void *ptr, Size numBytes)
 directly read from the stream
virtual void Seek (Offset offset, SeekOrigin origin)
 seek in stream
virtual void Flush ()
 flush unsaved data
bool IsMapped () const
 return true if stream is currently mapped to memory
int GetRefCount () const
 get the current refcount
void AddRef ()
 increment refcount by one
void Release ()
 decrement refcount and destroy object if refcount is zero
bool IsInstanceOf (const Rtti &rtti) const
 return true if this object is instance of given class
bool IsInstanceOf (const Util::String &className) const
 return true if this object is instance of given class by string
bool IsInstanceOf (const Util::FourCC &classFourCC) const
 return true if this object is instance of given class by fourcc
bool IsA (const Rtti &rtti) const
 return true if this object is instance of given class, or a derived class
bool IsA (const Util::String &rttiName) const
 return true if this object is instance of given class, or a derived class, by string
bool IsA (const Util::FourCC &rttiFourCC) const
 return true if this object is instance of given class, or a derived class, by fourcc
const Util::StringGetClassName () const
 get the class name
Util::FourCC GetClassFourCC () const
 get the class FourCC code

Static Public Member Functions

static void DumpRefCountingLeaks ()
 dump refcounting leaks, call at end of application (NEBULA3_DEBUG builds only!)

Member Function Documentation

bool IO::ZipFileStream::Open (  )  [virtual]

open the stream

Open the stream for reading. This will decompress the entire file from the zip archive into memory.

Reimplemented from IO::Stream.

void IO::Stream::SetURI ( const URI u  )  [inherited]

set stream location as URI

Set the URI of the stream as string. The URI identifies the source resource of the stream.

const URI & IO::Stream::GetURI (  )  const [inherited]

get stream URI

Get the URI of the stream as string.

void IO::Stream::SetSize ( Size  s  )  [virtual, inherited]

set a new size for the stream

This sets a new size for the stream. Not all streams support this method. If the new size if smaller then the existing size, the contents will be clipped.

void IO::Stream::SetAccessMode ( AccessMode  m  )  [inherited]

set the access mode of the stream (default is ReadAccess)

This method sets the intended access mode of the stream. The actual behaviour depends on the implementation of the derived class. The default is ReadWrite.

Stream::AccessMode IO::Stream::GetAccessMode (  )  const [inherited]

get the access mode of the stream

Get the access mode of the stream.

void IO::Stream::SetAccessPattern ( AccessPattern  p  )  [inherited]

set the prefered access pattern (default is Sequential)

Set the prefered access pattern of the stream. This can be Random or Sequential. This is an optional flag to improve performance with some stream implementations. The default is sequential. The pattern cannot be changed while the stream is open.

Stream::AccessPattern IO::Stream::GetAccessPattern (  )  const [inherited]

get the prefered access pattern

Get the currently set prefered access pattern of the stream.

bool IO::Stream::IsOpen (  )  const [inherited]

return true if currently open

Return true if the stream is currently open.

void IO::Stream::Write ( const void *  ptr,
Size  numBytes 
) [virtual, inherited]

directly write to the stream

Write raw data to the stream. For more convenient writing, attach the stream to an IO::StreamWriter object. This method is only valid if the stream class returns true in CanWrite().

Stream::Size IO::Stream::Read ( void *  ptr,
Size  numBytes 
) [virtual, inherited]

directly read from the stream

Read raw data from the stream. For more convenient reading, attach the stream to an IO::StreamReader object. The method returns the number of bytes actually read. This method is only valid if the stream class returns true in CanRead(). Returns the number of bytes actually read from the stream, this may be less then numBytes, or 0 if end-of-stream is reached.

void IO::Stream::Seek ( Offset  offset,
SeekOrigin  origin 
) [virtual, inherited]

seek in stream

Move the read/write cursor to a new position, returns the new position in the stream. This method is only supported if the stream class returns true in CanSeek().

void IO::Stream::Flush (  )  [virtual, inherited]

flush unsaved data

Flush any unsaved data. Note that unsaved data will also be flushed automatically when the stream is closed.

Reimplemented in IO::FileStream.

bool IO::Stream::IsMapped (  )  const [inherited]

return true if stream is currently mapped to memory

Returns true if the stream is currently mapped.

int Core::RefCounted::GetRefCount (  )  const [inline, inherited]

get the current refcount

Return the current refcount of the object.

void Core::RefCounted::AddRef (  )  [inline, inherited]

increment refcount by one

Increment the refcount of the object.

void Core::RefCounted::Release (  )  [inline, inherited]

decrement refcount and destroy object if refcount is zero

Decrement the refcount and destroy object if refcount is zero.

const Util::String & Core::RefCounted::GetClassName (  )  const [inline, inherited]

get the class name

Get the class name of the object.

Util::FourCC Core::RefCounted::GetClassFourCC (  )  const [inline, inherited]

get the class FourCC code

Get the class FourCC of the object.

void Core::RefCounted::DumpRefCountingLeaks (  )  [static, inherited]

dump refcounting leaks, call at end of application (NEBULA3_DEBUG builds only!)

This method should be called as the very last before an application exits.