MIDI_IO Class Reference

Virtual base for all MIDI I/O classes. More...

Inheritance diagram for MIDI_IO:

List of all members.

Public Types
Public type definitions and constants
enum	Io_mode { io_read = 1, io_write = 2, io_readwrite = 4 }
	Input/Output mode. More...
Public Member Functions
Constructors and destructors
virtual MIDI_IO *	clone (void) const =0
	Virtual method that clones the current object and returns a pointer to it.
virtual MIDI_IO *	new_expr (void) const =0
	Virtual method that creates a new object of current type.
	MIDI_IO (const std::string &name="unknown", int mode=io_read)
Attribute functions
virtual int	supported_io_modes (void) const
	Returns info about supported I/O modes (bitwise-OR).
virtual bool	supports_nonblocking_mode (void) const
	Whether device supports non-blocking I/O mode.
Configuration
For setting and getting configuration parameters.
int	io_mode (void) const
	Returns info about the current I/O mode.
const std::string &	label (void) const
	Returns the current label.
void	io_mode (int mode)
	Set object input/output-mode.
void	label (const std::string &id_label)
	Sets object label.
void	toggle_nonblocking_mode (bool value)
	Enable/disbale nonblocking mode.
virtual std::string	parameter_names (void) const
	A comma-separated list of parameters names.
virtual void	set_parameter (int param, std::string value)
	Sets the parameter value.
virtual std::string	get_parameter (int param) const
	Get parameter value.
Main functionality
virtual long int	read_bytes (void *target_buffer, long int bytes)=0
	Low-level routine for reading MIDI bytes.
virtual long int	write_bytes (void *target_buffer, long int bytes)=0
	Low-level routine for writing MIDI bytes.
virtual void	open (void)=0
	Opens the MIDI object (possibly in exclusive mode).
virtual void	close (void)=0
	Closes the MIDI object.
Runtime information
virtual int	poll_descriptor (void) const
	Returns a file descriptor id suitable for poll() and select() system calls.
bool	is_open (void) const
	Has device been opened (with open())?
virtual bool	finished (void) const =0
	Whether all data has been processed? If opened in mode 'io_read', this means that end of stream has been reached.
virtual bool	nonblocking_mode (void) const
	Is nonblocking mode is enabled?
virtual bool	readable (void) const
	Is the MIDI object ready for reading?
virtual bool	writable (void) const
	Is the MIDI object ready for writing?
Protected Member Functions
void	toggle_open_state (bool value)
	Sets device's state to enabled or disabled.

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Detailed Description

Virtual base for all MIDI I/O classes.

• type definitions

• attributes

• configuration (setting and getting configuration parameters)

• functionality (control and runtime information)

• runtime information

• constructors and destructors

Author:

Kai Vehmanen

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Member Enumeration Documentation

enum MIDI_IO::Io_mode

Input/Output mode. See also: io_mode() io_read Object is opened for input. If opening a file, it must exist. io_write Object is opened for output. If opening a file and and output exists, it is first truncated. io_readwrite Object is opened for both reading and writing. If opening a file, a new file is created if needed. When switching from read to write or vica versa, position should be reset before using the device.

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Member Function Documentation

virtual MIDI_IO* MIDI_IO::clone (  void   )  const [pure virtual]

Virtual method that clones the current object and returns a pointer to it. This must be implemented by all subclasses! Implements DYNAMIC_OBJECT< std::string >. Implemented in MIDI_IO_RAW.

virtual void MIDI_IO::close (  void   )  [pure virtual]

Closes the MIDI object. After calling this routine, all resources (ie. soundcard) must be freed (they can be used by other processes). ensure: readable() != true writable() != true Implemented in MIDI_IO_RAW.

virtual bool MIDI_IO::finished (  void   )  const [pure virtual]

Whether all data has been processed? If opened in mode 'io_read', this means that end of stream has been reached. If opened in 'io_write' or 'io_readwrite' modes, finished status usually means that an error has occured (no space left, etc). After finished() has returned 'true', further calls to read() and/or write() won't process any data. Implemented in MIDI_IO_RAW.

std::string MIDI_IO::get_parameter (  int  param  )  const [virtual]

Get parameter value. Parameters: param  parameter id, require: param > 0 Implements DYNAMIC_PARAMETERS< std::string >. Reimplemented in MIDI_IO_RAW.

void MIDI_IO::io_mode (  int  mode  )

Set object input/output-mode. If the requested mode isn't supported, the nearest supported mode is used. Because of this, it's wise to afterwards check whether the requested mode was accepted. require: is_open() != true

void MIDI_IO::label (  const std::string &  id_label  )

Sets object label. Label is used to identify the object instance. Unlike ECA_OBJECT::name(), label() is not necessarily unique among different class instances. Device and file names are typical label values. require: is_open() != true

const std::string & MIDI_IO::label (  void   )  const

Returns the current label. See documentation for label(const std::string&).

virtual MIDI_IO* MIDI_IO::new_expr (  void   )  const [pure virtual]

Virtual method that creates a new object of current type. This must be implemented by all subclasses! Implements DYNAMIC_OBJECT< std::string >. Implemented in MIDI_IO_RAW.

virtual void MIDI_IO::open (  void   )  [pure virtual]

Opens the MIDI object (possibly in exclusive mode). This routine is meant for opening files and devices, loading libraries, etc. ensure: readable() == true || writable() == true Implemented in MIDI_IO_RAW.

virtual std::string MIDI_IO::parameter_names (  void   )  const [inline, virtual]

A comma-separated list of parameters names. Derived classes must implement this. Implements DYNAMIC_PARAMETERS< std::string >. Reimplemented in MIDI_IO_RAW.

virtual int MIDI_IO::poll_descriptor (  void   )  const [inline, virtual]

Returns a file descriptor id suitable for poll() and select() system calls. If polling is not supported, returns value of '-1'. Reimplemented in MIDI_IO_RAW.

virtual long int MIDI_IO::read_bytes (  void *  target_buffer, long int  bytes )  [pure virtual]

Low-level routine for reading MIDI bytes. Number of read bytes is returned. This must be implemented by all subclasses. Implemented in MIDI_IO_RAW.

void MIDI_IO::set_parameter (  int  param, std::string  value )  [virtual]

Sets the parameter value. Implementations should be able to handle arbitrary values of 'value'. Argument validity can be tested by a combination of set_parameter() and get_parameter() calls. Parameter value is valid, if get_parameter() returns it without changes. Parameters: param  parameter id, require: param > 0 value  new value Implements DYNAMIC_PARAMETERS< std::string >. Reimplemented in MIDI_IO_RAW.

int MIDI_IO::supported_io_modes (  void   )  const [virtual]

Returns info about supported I/O modes (bitwise-OR). By default, all I/O modes are supported. Reimplemented in MIDI_IO_RAW.

bool MIDI_IO::supports_nonblocking_mode (  void   )  const [virtual]

Whether device supports non-blocking I/O mode. By default, nonblocking mode is not supported. Reimplemented in MIDI_IO_RAW.

void MIDI_IO::toggle_nonblocking_mode (  bool  value  )

Enable/disbale nonblocking mode. require: is_open() != true

virtual long int MIDI_IO::write_bytes (  void *  target_buffer, long int  bytes )  [pure virtual]

Low-level routine for writing MIDI bytes. Number of bytes written is returned. This must be implemented by all subclasses. Implemented in MIDI_IO_RAW.

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

• midiio.h
• midiio.cpp

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