Dv::Util::filterstreambuf< Filter > Class Template Reference

A streambuf specialization that cooperates with a filter class object. More...

#include <filterstreambuf.h>

List of all members.

Public Member Functions
	filterstreambuf (Filter &filter)
	The constructor remembers the filter to which I/O will be forwarded.
virtual	~filterstreambuf ()
	This is already virtual in streambuf.
const Filter &	filter () const
Filter &	filter ()
filterstreambuf &	filter (Filter &filter)
	Set underlying filter.
bool	close ()
	Close -- indicate intention not to use the filter anymore.
virtual int	sync ()
	Override iostream::sync().
Protected Member Functions
virtual int	underflow ()
	Override iostream::underflow().
virtual int	overflow (int c)
	Override iostream::overflow().
Private Attributes
Filter &	filter_
char	inbuf_ [1]
char	outbuf_ [1]

---

Detailed Description

template<class Filter>
class Dv::Util::filterstreambuf< Filter >

A streambuf specialization that cooperates with a filter class object.

A filterstreambuf does not buffer data, but immediately passes them on (resp. obtains them from) to the filter.

The requirements for the Filter template parameter are as follows:

  class Filter {
  public:
    int get(); // return next input char or Traits::eof
    int put(int c); // output c if c!=EOF, return EOF if error
    int sync(); // synchronize filter, return 0 (ok) or -1 (EOF)
    void close(); // close filter, no obligations..
    ios_base::iostate state(); // return status of filter
  };

Here, state() is not used by filterstreambuf but may be convenient for streams based on a filterstreambuf: the constructor can use basic_ios::clear(filter.state()) to inherit the initial state of the filter.

See also:

Dv::Util::teestream

Definition at line 38 of file filterstreambuf.h.

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Constructor & Destructor Documentation

template<class Filter >

Dv::Util::filterstreambuf< Filter >::filterstreambuf

(

Filter &

filter

)

[inline, explicit]

The constructor remembers the filter to which I/O will be forwarded.

Parameters:

filter

to which I/O operations will be forwarded.

Warning:

The filter is not copied, the management of the filter is not the filterstreambuf's responsibility (only a reference to the filter is kept).

Definition at line 47 of file filterstreambuf.h.

References Dv::Util::filterstreambuf< Filter >::inbuf_, and Dv::Util::filterstreambuf< Filter >::outbuf_.

template<class Filter >

virtual Dv::Util::filterstreambuf< Filter >::~filterstreambuf

(

)

[inline, virtual]

This is already virtual in streambuf.

Definition at line 54 of file filterstreambuf.h.

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Member Function Documentation

template<class Filter >

const Filter& Dv::Util::filterstreambuf< Filter >::filter

(

)

const [inline]

Returns:

underlying filter (const version).

Definition at line 58 of file filterstreambuf.h.

References Dv::Util::filterstreambuf< Filter >::filter_.

template<class Filter >

Filter& Dv::Util::filterstreambuf< Filter >::filter

(

)

[inline]

Returns:

underlying filter (non-const version).

Definition at line 62 of file filterstreambuf.h.

References Dv::Util::filterstreambuf< Filter >::filter_.

template<class Filter >

filterstreambuf& Dv::Util::filterstreambuf< Filter >::filter

(

Filter &

filter

)

[inline]

Set underlying filter.

Parameters:

filter

to which I/O operations will be forwarded.

Warning:

The filter is not copied, the management of the filter is not the filterstreambuf's responsibility.

Definition at line 70 of file filterstreambuf.h.

References Dv::Util::filterstreambuf< Filter >::filter_.

template<class Filter >

bool Dv::Util::filterstreambuf< Filter >::close

(

)

[inline]

Close -- indicate intention not to use the filter anymore.

Returns:

return status of Dv::Util::filterstreambuf::sync.

Definition at line 75 of file filterstreambuf.h.

References Dv::Util::filterstreambuf< Filter >::filter_, and Dv::Util::filterstreambuf< Filter >::sync().

template<class Filter >

virtual int Dv::Util::filterstreambuf< Filter >::sync

(

)

[inline, virtual]

Override iostream::sync().

Returns:

return status of filter_.sync() .

Definition at line 80 of file filterstreambuf.h.

References Dv::Util::filterstreambuf< Filter >::filter_.

Referenced by Dv::Util::filterstreambuf< Filter >::close().

template<class Filter >

virtual int Dv::Util::filterstreambuf< Filter >::underflow

(

)

[inline, protected, virtual]

Override iostream::underflow().

Returns:

next input char or EOF

Definition at line 86 of file filterstreambuf.h.

References Dv::Util::filterstreambuf< Filter >::filter_, and Dv::Util::filterstreambuf< Filter >::inbuf_.

template<class Filter >

virtual int Dv::Util::filterstreambuf< Filter >::overflow

(

int

c

)

[inline, protected, virtual]

Override iostream::overflow().

Parameters:

c

next char to put

Returns:

status of filter_.put(c)

Definition at line 98 of file filterstreambuf.h.

References Dv::Util::filterstreambuf< Filter >::filter_.

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Member Data Documentation

template<class Filter >

Filter& Dv::Util::filterstreambuf< Filter >::filter_ [private]

Definition at line 101 of file filterstreambuf.h.

Referenced by Dv::Util::filterstreambuf< Filter >::close(), Dv::Util::filterstreambuf< Filter >::filter(), Dv::Util::filterstreambuf< Filter >::overflow(), Dv::Util::filterstreambuf< Filter >::sync(), and Dv::Util::filterstreambuf< Filter >::underflow().

template<class Filter >

char Dv::Util::filterstreambuf< Filter >::inbuf_[1] [private]

Definition at line 102 of file filterstreambuf.h.

Referenced by Dv::Util::filterstreambuf< Filter >::filterstreambuf(), and Dv::Util::filterstreambuf< Filter >::underflow().

template<class Filter >

char Dv::Util::filterstreambuf< Filter >::outbuf_[1] [private]

Definition at line 103 of file filterstreambuf.h.

Referenced by Dv::Util::filterstreambuf< Filter >::filterstreambuf().

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

• filterstreambuf.h