This class is used to allow a block of memory to substitute for a disk file. More...

#include <memfile.h>

Inheritance diagram for PMemoryFile:

Collaboration diagram for PMemoryFile:

Public Member Functions
Construction
	PMemoryFile ()
	Create a new, empty, memory file. More...

	PMemoryFile (const PBYTEArray &data)
	Create a new memory file initialising to the specified content. More...

	~PMemoryFile ()
	Destroy the memory file. More...

Overrides from class PObject
Comparison	Compare (const PObject &obj) const
	Determine the relative rank of the two objects. More...

Overrides from class PChannel
virtual PBoolean	Open (OpenMode mode=ReadWrite, int opts=ModeDefault)
	Open the current file in the specified mode and with the specified options. More...

virtual PBoolean	Open (const PFilePath &name, OpenMode mode=ReadWrite, int opts=ModeDefault)
	Open the specified file name in the specified mode and with the specified options. More...

virtual PBoolean	Close ()
	Close the channel, shutting down the link to the data source. More...

virtual PBoolean	Read (void *buf, PINDEX len)
	Low level read from the memory file channel. More...

virtual PBoolean	Write (const void *buf, PINDEX len)
	Low level write to the memory file channel. More...

Overrides from class PFile
virtual off_t	GetLength () const
	Get the current size of the file. More...

virtual PBoolean	SetLength (off_t len)
	Set the size of the file, padding with 0 bytes if it would require expanding the file, or truncating it if being made shorter. More...

virtual PBoolean	SetPosition (off_t pos, FilePositionOrigin origin=Start)
	Set the current active position in the file for the next read or write operation. More...

virtual off_t	GetPosition () const
	Get the current active position in the file for the next read or write operation. More...

const PBYTEArray &	GetData () const
	Get the memory data the file has operated with. More...

Public Member Functions inherited from PFile
virtual PString	GetName () const
	Get the platform and I/O channel type name of the channel. More...

	PFile ()
	Create a file object but do not open it. More...

	P_DECLARE_BITWISE_ENUM_EX (OpenOptions, 7,(NoOptions, MustExist, Create, Truncate, Exclusive, Temporary, DenySharedRead, DenySharedWrite), ModeDefault=-1)
	When a file is opened, a number of options may be associated with the open file. More...

	PFile (OpenMode mode, OpenOptions opts=ModeDefault)
	Create a unique temporary file name, and open the file in the specified mode and using the specified options. More...

	PFile (const PFilePath &name, OpenMode mode=ReadWrite, OpenOptions opts=ModeDefault)
	Create a file object with the specified name and open it in the specified mode and with the specified options. More...

	~PFile ()
	Close the file on destruction. More...

bool	Exists () const
	Check for file existance. More...

bool	Access (OpenMode mode)
	Check for file access modes. More...

bool	Remove (bool force=false)
	Delete the current file. More...

bool	Rename (const PString &newname, bool force=false)
	Change the current files name. More...

bool	Copy (const PFilePath &newname, bool force=false, bool recurse=false)
	Make a copy of the current file. More...

bool	Move (const PFilePath &newname, bool force=false, bool recurse=false)
	Move the current file. More...

const PFilePath &	GetFilePath () const
	Get the full path name of the file. More...

void	SetFilePath (const PString &path)
	Set the full path name of the file. More...

virtual PBoolean	Open (OpenMode mode=ReadWrite, OpenOptions opts=ModeDefault)
	Open the current file in the specified mode and with the specified options. More...

virtual PBoolean	Open (OpenMode mode, OpenOptions opts, PFileInfo::Permissions permissions)
	Open the specified file name in the specified mode and with the specified options and permissions. More...

virtual PBoolean	Open (const PFilePath &name, OpenMode mode=ReadWrite, OpenOptions opts=ModeDefault)
	Open the specified file name in the specified mode and with the specified options. More...

virtual PBoolean	Open (const PFilePath &name, OpenMode mode, OpenOptions opts, PFileInfo::Permissions permissions)
	Open the specified file name in the specified mode and with the specified options and permissions. More...

bool	IsEndOfFile () const
	Determine if the current file position is at the end of the file. More...

bool	GetInfo (PFileInfo &info)
	Get information (eg protection, timestamps) on the current file. More...

bool	SetPermissions (PFileInfo::Permissions permissions)
	Set permissions on the current file. More...

Public Member Functions inherited from PChannel
PBoolean	SetErrorValues (Errors errorCode, int osError, ErrorGroup group=LastGeneralError)
	Set error values to those specified. More...

virtual PINDEX	HashFunction () const
	Calculate a hash value for use in sets and dictionaries. More...

virtual PBoolean	IsOpen () const
	Determine if the channel is currently open. More...

virtual P_INT_PTR	GetHandle () const
	Get the integer operating system handle for the channel. More...

FILE *	FDOpen (const char *mode)
	Re-open the device using the stdio library. More...

virtual PChannel *	GetBaseReadChannel () const
	Get the base channel of channel indirection using PIndirectChannel. More...

virtual PChannel *	GetBaseWriteChannel () const
	Get the base channel of channel indirection using PIndirectChannel. More...

void	SetReadTimeout (const PTimeInterval &time)
	Set the timeout for read operations. More...

PTimeInterval	GetReadTimeout () const
	Get the timeout for read operations. More...

PINDEX	GetLastReadCount () const
	Get the number of bytes read by the last Read() call. More...

virtual int	ReadChar ()
	Read a single character from the channel. More...

PBoolean	ReadBlock (void *buf, PINDEX len)
	Read len bytes into the buffer from the channel. More...

PString	ReadString (PINDEX len)
	Read `len` character into a string from the channel. More...

void	SetWriteTimeout (const PTimeInterval &time)
	Set the timeout for write operations to complete. More...

PTimeInterval	GetWriteTimeout () const
	Get the timeout for write operations to complete. More...

virtual PBoolean	Write (const void buf, PINDEX len, const void )
	Low level write to the channel with marker. More...

virtual PINDEX	GetLastWriteCount () const
	Get the number of bytes written by the last Write() call. More...

PBoolean	WriteChar (int c)
	Write a single character to the channel. More...

PBoolean	WriteString (const PString &str)
	Write a string to the channel. More...

	~PChannel ()
	Close down the channel. More...

Errors	GetErrorCode (ErrorGroup group=NumErrorGroups) const
	Get normalised error code. More...

int	GetErrorNumber (ErrorGroup group=NumErrorGroups) const
	Get OS errro code. More...

virtual PString	GetErrorText (ErrorGroup group=NumErrorGroups) const
	Get error message description. More...

virtual bool	ReadAsync (AsyncContext &context)
	Begin an asynchronous read from channel. More...

virtual void	OnReadComplete (AsyncContext &context)
	User callback function for when a `ReadAsync()` call has completed or timed out. More...

virtual bool	WriteAsync (AsyncContext &context)
	Begin an asynchronous write from channel. More...

virtual void	OnWriteComplete (AsyncContext &context)
	User callback function for when a WriteAsync() call has completed or timed out. More...

virtual PBoolean	Shutdown (ShutdownValue option)
	Close one or both of the data streams associated with a channel. More...

virtual bool	SetLocalEcho (bool localEcho)
	Set local echo mode. More...

virtual bool	FlowControl (const void *flowData)
	Flow Control information Pass data to the channel for flowControl determination. More...

PBoolean	SetBufferSize (PINDEX newSize)
	Set the iostream buffer size for reads and writes. More...

PBoolean	SendCommandString (const PString &command)
	Send a command meta-string. More...

void	AbortCommandString ()
	Abort a command string that is in progress. More...

Public Member Functions inherited from PObject
unsigned	GetTraceContextIdentifier () const
	Get PTRACE context identifier. More...

void	SetTraceContextIdentifier (unsigned id)

void	GetTraceContextIdentifier (PObject &obj)

void	GetTraceContextIdentifier (PObject *obj)

void	SetTraceContextIdentifier (const PObject &obj)

void	SetTraceContextIdentifier (const PObject *obj)

virtual	~PObject ()

virtual PObject *	Clone () const
	Create a copy of the class on the heap. More...

template<class CLS >
CLS *	CloneAs () const
	As for Clone() but converts to specified type. More...

virtual Comparison	CompareObjectMemoryDirect (const PObject &obj) const
	Determine the byte wise comparison of two objects. More...

bool	operator== (const PObject &obj) const
	Compare the two objects. More...

bool	operator!= (const PObject &obj) const
	Compare the two objects. More...

bool	operator< (const PObject &obj) const
	Compare the two objects. More...

bool	operator> (const PObject &obj) const
	Compare the two objects. More...

bool	operator<= (const PObject &obj) const
	Compare the two objects. More...

bool	operator>= (const PObject &obj) const
	Compare the two objects. More...

virtual const char *	GetClass (unsigned ancestor=0) const
	Get the current dynamic type of the object instance. More...

PBoolean	IsClass (const char *cls) const

virtual PBoolean	InternalIsDescendant (const char *clsName) const
	Determine if the dynamic type of the current instance is a descendent of the specified class. More...

__inline const PObject *	PTraceObjectInstance () const

virtual void	PrintOn (ostream &strm) const
	Output the contents of the object to the stream. More...

virtual void	ReadFrom (istream &strm)
	Input the contents of the object from the stream. More...

Protected Attributes
PBYTEArray	m_data

off_t	m_position

Protected Attributes inherited from PFile
PFilePath	m_path
	The fully qualified path name for the file. More...

bool	m_removeOnClose
	File is to be removed when closed. More...

Protected Attributes inherited from PChannel
P_INT_PTR	os_handle
	The operating system file handle return by standard open() function. More...

Errors	lastErrorCode [NumErrorGroups+1]
	The platform independant error code. More...

int	lastErrorNumber [NumErrorGroups+1]
	The operating system error number (eg as returned by errno). More...

PINDEX	lastReadCount
	Number of byte last read by the Read() function. More...

PINDEX	lastWriteCount
	Number of byte last written by the Write() function. More...

PTimeInterval	readTimeout
	Timeout for read operations. More...

PTimeInterval	writeTimeout
	Timeout for write operations. More...

PString	channelName
	Name of channel. More...

PMutex	px_threadMutex

PXBlockType	px_lastBlockType

PThread *	px_readThread

PThread *	px_writeThread

PMutex	px_writeMutex

PThread *	px_selectThread [3]

PMutex	px_selectMutex [3]

Protected Attributes inherited from PObject
unsigned	m_traceContextIdentifier

Additional Inherited Members
Public Types inherited from PFile
enum	OpenMode { ReadOnly, WriteOnly, ReadWrite }
	When a file is opened, it may restrict the access available to operations on the object instance. More...

enum	FilePositionOrigin { Start = SEEK_SET, Current = SEEK_CUR, End = SEEK_END }
	Options for the origin in setting the file position. More...

Public Types inherited from PChannel
enum	PXBlockType { PXReadBlock, PXWriteBlock, PXAcceptBlock, PXConnectBlock }

enum	Errors { NoError, NotFound, FileExists, DiskFull, AccessDenied, DeviceInUse, BadParameter, NoMemory, NotOpen, Timeout, Interrupted, BufferTooSmall, Miscellaneous, ProtocolFailure, Unavailable, NumNormalisedErrors }
	Normalised error codes. More...

enum	ErrorGroup { LastReadError, LastWriteError, LastGeneralError, NumErrorGroups }
	Error groups. More...

typedef PNotifierTemplate < PChannel::AsyncContext & >	AsyncNotifier

enum	ShutdownValue { ShutdownRead = 0, ShutdownWrite = 1, ShutdownReadAndWrite = 2 }

Static Public Member Functions inherited from PFile
static bool	Exists (const PFilePath &name)
	Check for file existance. More...

static bool	Access (const PFilePath &name, OpenMode mode)
	Check for file access modes. More...

static bool	Remove (const PFilePath &name, bool force=false)
	Delete the specified file. More...

static bool	Remove (const PString &name, bool force=false)

static bool	Rename (const PFilePath &oldname, const PString &newname, bool force=false)
	Change the specified files name. More...

static bool	Copy (const PFilePath &oldname, const PFilePath &newname, bool force=false, bool recurse=false)
	Make a copy of the specified file. More...

static bool	Move (const PFilePath &oldname, const PFilePath &newname, bool force=false, bool recurse=false)
	Move the specified file. More...

static bool	GetInfo (const PFilePath &name, PFileInfo &info)
	Get information (eg protection, timestamps) on the specified file. More...

static bool	SetPermissions (const PFilePath &name, PFileInfo::Permissions permissions)
	Set permissions on the specified file. More...

Static Public Member Functions inherited from PChannel
static PString	GetErrorText (Errors lastError, int osError=0)
	Get error message description. More...

Static Public Member Functions inherited from PObject
static Comparison	InternalCompareObjectMemoryDirect (const PObject obj1, const PObject obj2, PINDEX size)
	Internal function caled from CompareObjectMemoryDirect() More...

static const char *	Class ()
	Get the name of the class as a C string. More...

static __inline const PObject *	PTraceObjectInstance (const char *)

static __inline const PObject *	PTraceObjectInstance (const PObject *obj)

Protected Member Functions inherited from PChannel
	PChannel (const PChannel &)

PChannel &	operator= (const PChannel &)

virtual PBoolean	ConvertOSError (P_INT_PTR libcReturnValue, ErrorGroup group=LastGeneralError)
	Convert an operating system error into platform independent error. More...

int	ReadCharWithTimeout (PTimeInterval &timeout)
	Read a character with specified timeout. More...

PBoolean	ReceiveCommandString (int nextChar, const PString &reply, PINDEX &pos, PINDEX start)

virtual int	os_errno () const

PBoolean	PXSetIOBlock (PXBlockType type, const PTimeInterval &timeout)

P_INT_PTR	GetOSHandleAsInt () const

int	PXClose ()

	PChannel ()
	Create the channel. More...

Friends inherited from PObject

Detailed Description

This class is used to allow a block of memory to substitute for a disk file.

Constructor & Destructor Documentation

PMemoryFile::PMemoryFile ( )

Create a new, empty, memory file.

PMemoryFile::PMemoryFile ( const PBYTEArray & data )

Create a new memory file initialising to the specified content.

Parameters

data	New content filr memory file.

PMemoryFile::~PMemoryFile ( )

Destroy the memory file.

Member Function Documentation

virtual PBoolean PMemoryFile::Close ( )

virtual

Close the channel, shutting down the link to the data source.

Returns: true if the channel successfully closed.

Reimplemented from PFile.

Comparison PMemoryFile::Compare ( const PObject & obj ) const

virtual

Determine the relative rank of the two objects.

This is essentially the string comparison of the PFilePath names of the files.

Returns: relative rank of the file paths.

Parameters

obj	Other file to compare against.

Reimplemented from PFile.

const PBYTEArray& PMemoryFile::GetData ( ) const

inline

Get the memory data the file has operated with.

References m_data.

virtual off_t PMemoryFile::GetLength ( ) const

virtual

Get the current size of the file.

The size of the file corresponds to the size of the data array.

Returns: length of file in bytes.

Reimplemented from PFile.

virtual off_t PMemoryFile::GetPosition ( ) const

virtual

Get the current active position in the file for the next read or write operation.

Returns: current file position relative to start of file.

Reimplemented from PFile.

virtual PBoolean PMemoryFile::Open	(	OpenMode	mode = `ReadWrite`,
		int	opts = `ModeDefault`
	)

virtual

Open the current file in the specified mode and with the specified options.

If the file object already has an open file then it is closed.

If there has not been a filename attached to the file object (via SetFilePath(), the name parameter or a previous open) then a new unique temporary filename is generated.

Returns: true if the file was successfully opened.

virtual PBoolean PMemoryFile::Open	(	const PFilePath &	name,
		OpenMode	mode = `ReadWrite`,
		int	opts = `ModeDefault`
	)

virtual

Open the specified file name in the specified mode and with the specified options.

If the file object already has an open file then it is closed.

Note: if mode is StandardInput, StandardOutput or StandardError, then the name parameter is ignored.

Returns: true if the file was successfully opened.

virtual PBoolean PMemoryFile::Read	(	void *	buf,
		PINDEX	len
	)

virtual

Low level read from the memory file channel.

The read timeout is ignored. The GetLastReadCount() function returns the actual number of bytes read.

The GetErrorCode() function should be consulted after Read() returns false to determine what caused the failure.

Returns: true indicates that at least one character was read from the channel. false means no bytes were read due to timeout or some other I/O error.

Parameters

buf	Pointer to a block of memory to receive the read bytes.
len	Maximum number of bytes to read into the buffer.

Reimplemented from PFile.

virtual PBoolean PMemoryFile::SetLength ( off_t len )

virtual

Set the size of the file, padding with 0 bytes if it would require expanding the file, or truncating it if being made shorter.

Returns: true if the file size was changed to the length specified.

Parameters

len	New length of file.

Reimplemented from PFile.

virtual PBoolean PMemoryFile::SetPosition	(	off_t	pos,
		FilePositionOrigin	origin = `Start`
	)

virtual

Set the current active position in the file for the next read or write operation.

The pos variable is a signed number which is added to the specified origin. For origin == PFile::Start only positive values for pos are meaningful. For origin == PFile::End only negative values for pos are meaningful.

Returns: true if the new file position was set.

Parameters

pos	New position to set.
origin	Origin for position change.

Reimplemented from PFile.

virtual PBoolean PMemoryFile::Write	(	const void *	buf,
		PINDEX	len
	)

virtual

Low level write to the memory file channel.

The write timeout is ignored. The GetLastWriteCount() function returns the actual number of bytes written.

The GetErrorCode() function should be consulted after Write() returns false to determine what caused the failure.

Returns: true if at least len bytes were written to the channel.

Parameters

buf	Pointer to a block of memory to write.
len	Number of bytes to write.

Reimplemented from PFile.

Member Data Documentation

PBYTEArray PMemoryFile::m_data

protected

Referenced by GetData().

off_t PMemoryFile::m_position

protected

The documentation for this class was generated from the following file:

memfile.h

Public Member Functions

Protected Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation