PoDoFo::InputStream Class Reference

An interface for reading blocks of data from a data source. More...

#include <InputStream.h>

Inheritance diagram for PoDoFo::InputStream:

Public Member Functions
void	Read (char *buffer, size_t size)
	Read data from the device.
size_t	Read (char *buffer, size_t size, bool &eof)
	Read data from the device.
char	ReadChar ()
	Get next char from stream.
bool	Read (char &ch)
	Get next char from stream.
void	CopyTo (OutputStream &stream)
	Copy this stream to another.
void	CopyTo (OutputStream &stream, size_t size)
	Copy this stream to another.

Protected Member Functions
virtual size_t	readBuffer (char *buffer, size_t size, bool &eof)=0
	Read a buffer from the stream.
virtual bool	readChar (char &ch)
	Read the next char in stream.
virtual void	checkRead () const
	Optional checks before reading By default does nothing.

Static Protected Member Functions
static size_t	ReadBuffer (InputStream &stream, char *buffer, size_t size, bool &eof)
	Read from another stream, to be used by decorator streams on their source.
static bool	ReadChar (InputStream &stream, char &ch)

Protected Attributes
const char *	m_head
	Inline read window over memory that already holds the bytes at the current logical position.
const char *	m_tail

Detailed Description

An interface for reading blocks of data from a data source.

It supports non-blocking read operations

Member Function Documentation

checkRead()

void InputStream::checkRead ( ) const

protectedvirtual

Optional checks before reading By default does nothing.

Reimplemented in PoDoFo::InputStreamDevice.

CopyTo() [1/2]

void InputStream::CopyTo

(

OutputStream &

stream

)

Copy this stream to another.

Remarks

The copy begins from the current position and it's not reset after the operation is completed

CopyTo() [2/2]

void InputStream::CopyTo	(	OutputStream &	stream,
		size_t	size
	)

Copy this stream to another.

Remarks

The copy begins from the current position and it's not reset after the operation is completed

Read() [1/3]

PODOFO_INLINE bool InputStream::Read

(

char &

ch

)

Get next char from stream.

Parameters

ch	the read character

Returns

true if success, false if EOF is encountered before reading the character

Read() [2/3]

PODOFO_INLINE void InputStream::Read	(	char *	buffer,
		size_t	size
	)

Read data from the device.

Parameters

buffer	a pointer to the data buffer
size	length of the output buffer

Remarks

throws if EOF is encountered before reading the required size

Read() [3/3]

PODOFO_INLINE size_t InputStream::Read	(	char *	buffer,
		size_t	size,
		bool &	eof
	)

Read data from the device.

Parameters

buffer	a pointer to the data buffer
size	length of the output buffer
eof	stream encountered EOF during the read

Returns

Number of read bytes

readBuffer()

virtual size_t PoDoFo::InputStream::readBuffer ( char *  buffer, size_t  size, bool &  eof  )

protectedpure virtual

Read a buffer from the stream.

Parameters

eof	true if the stream reached eof during read

Returns

number of read bytes

Implemented in PoDoFo::NullStreamDevice, and PoDoFo::PdfCanvasInputDevice.

ReadBuffer()

PODOFO_INLINE size_t InputStream::ReadBuffer ( InputStream &  stream, char *  buffer, size_t  size, bool &  eof  )

staticprotected

Read from another stream, to be used by decorator streams on their source.

Like the public frontends they serve the source read window first, when it can satisfy the request

ReadChar()

PODOFO_INLINE char InputStream::ReadChar

(

)

Get next char from stream.

Returns

the next character from the stream

Remarks

throws if EOF is encountered before reading the character

readChar()

bool InputStream::readChar ( char &  ch )

protectedvirtual

Read the next char in stream.

Returns

true if success, false if EOF

Reimplemented in PoDoFo::NullStreamDevice, and PoDoFo::PdfCanvasInputDevice.

Member Data Documentation

m_head

const char* PoDoFo::InputStream::m_head

protected

Inline read window over memory that already holds the bytes at the current logical position.

It has three states:

• unarmed: m_tail == nullptr, the device counter owns the position
• armed, empty: m_tail != nullptr && m_head == m_tail, the window is authoritative for the position but holds no bytes
• armed, non empty: m_head < m_tail, reads are served from the window While armed m_head is authoritative for the logical position, so every readBuffer()/readChar()/peek() override of an arming device must drain or derive from it. The window is armed only when read access is granted, since the fast paths skip checkRead()

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

• src/podofo/auxiliary/InputStream.h
• src/podofo/auxiliary/InputStream.cpp