libcommonc++  0.7
Stream Class Reference

An unbuffered I/O stream. More...

#include <Stream.h++>

Inheritance diagram for Stream:

Public Member Functions

virtual ~Stream ()
 Destructor. More...
 
virtual size_t read (ByteBuffer &buffer)
 Read data from the stream into a ByteBuffer. More...
 
virtual size_t read (CharBuffer &buffer)
 Read data from the stream into a CharBuffer. More...
 
template<typename T >
size_t read (Buffer< T > &buffer, size_t &partial)
 Read data from the stream into a Buffer of arbitrary type. More...
 
virtual size_t read (byte_t *buffer, size_t buflen)
 Read data from the stream into a raw buffer. More...
 
size_t read (byte_t *buffer, size_t buflen, int64_t offset, AsyncIOTask &task)
 Read data asynchronously from the stream into a raw buffer. More...
 
size_t read (ByteBuffer &buffer, int64_t offset, AsyncIOTask &task)
 Read data asynchronously from the stream into a Buffer. More...
 
size_t write (const byte_t *buffer, size_t buflen, int64_t offset, AsyncIOTask &task)
 Write data asynchronously to the stream from a raw buffer. More...
 
size_t write (ByteBuffer &buffer, int64_t offset, AsyncIOTask &task)
 Write data asynchronously to the stream from a Buffer. More...
 
virtual size_t readFully (ByteBuffer &buffer, size_t count=0)
 Read data from the stream into a ByteBuffer, until either the buffer is full or an error or timeout occurs. More...
 
virtual size_t readFully (CharBuffer &buffer, size_t count=0)
 Read data from the stream into a CharBuffer, until either the buffer is full or an error or timeout occurs. More...
 
template<typename T >
size_t readFully (Buffer< T > &buffer, size_t &partial)
 Read data from the stream into a Buffer of arbitrary type, until either the buffer is full or an error or timeout occurs. More...
 
virtual size_t readFully (byte_t *buffer, size_t buflen)
 Read data from the stream into a raw buffer, until either the buffer is full or an error or timeout occurs. More...
 
virtual size_t read (MemoryBlock *vec, uint_t count)
 Read data from the stream into a series of I/O buffers. More...
 
virtual size_t write (ByteBuffer &buffer)
 Write data to the stream from a ByteBuffer. More...
 
virtual size_t write (CharBuffer &buffer)
 Write data to the stream from a CharBuffer. More...
 
template<typename T >
size_t write (Buffer< T > &buffer, size_t &partial)
 Write data to the stream from a Buffer of arbitrary type. More...
 
virtual size_t write (const byte_t *buffer, size_t buflen)
 Write data to the stream from a raw buffer, until either the entire buffer is written or an error or timeout occurs. More...
 
virtual size_t writeFully (ByteBuffer &buffer)
 Write data to the stream from a ByteBuffer, until either the entire buffer is written or an error or timeout occurs. More...
 
virtual size_t writeFully (CharBuffer &buffer)
 Write data to the stream from a CharBuffer, until either the entire buffer is written or an error or timeout occurs. More...
 
template<typename T >
size_t writeFully (Buffer< T > &buffer, size_t &partial)
 Write data to the stream from a Buffer of arbitrary type, until either the entire buffer is written or an error or timeout occurs. More...
 
virtual size_t writeFully (const byte_t *buffer, size_t buflen)
 Write data to the stream from a raw buffer. More...
 
virtual size_t write (const MemoryBlock *vec, uint_t count)
 Write data to the stream from a series of I/O buffers. More...
 
virtual int64_t seek (int64_t offset, SeekMode mode=SeekAbsolute)
 Reposition the seek pointer in the stream. More...
 
virtual int64_t tell ()
 Get the current (absolute) offset of the seek pointer. More...
 
bool isOpen () const
 Test if the stream is open. More...
 
bool isSeekable () const
 Test if the stream supports seeking. More...
 
bool isReadable () const
 Test if the stream can be read from. More...
 
bool isWritable () const
 Test if the stream can be written to. More...
 
bool isFullDuplex () const
 Test if the stream is full-duplex (i.e., supports both reading and writing). More...
 
bool isHalfDuplex () const
 Test if the stream is half-duplex (i.e., supports either reading or writing, but not both). More...
 
virtual void close (IOMode mode=IOReadWrite)
 Close the stream for reading, writing, or both. More...
 
virtual void setTimeout (timespan_ms_t timeout)
 Set the stream I/O timeout, in milliseconds. More...
 
timespan_ms_t getTimeout () const
 Get the stream I/O timeout, in milliseconds. More...
 

Static Public Attributes

static const uint_t MAX_IOBLOCK_COUNT = 16
 The maximum number of I/O buffers that can be passed to the vector I/O methods. More...
 

Protected Member Functions

 Stream ()
 Construct a new, uninitialized Stream. More...
 
 Stream (FileHandle handle, bool seekable=true, bool readable=true, bool writable=true)
 Construct a new stream. More...
 
void _init (FileHandle handle, bool seekable, bool readable, bool writable)
 Initialize the stream for use with an open file. More...
 

Friends

class Process
 

Detailed Description

An unbuffered I/O stream.

Author
Mark Lindner

Constructor & Destructor Documentation

◆ Stream() [1/2]

Stream ( )
protected

Construct a new, uninitialized Stream.

◆ Stream() [2/2]

Stream ( FileHandle  handle,
bool  seekable = true,
bool  readable = true,
bool  writable = true 
)
protected

Construct a new stream.

Parameters
handleThe handle to an open file.
seekableA flag indicating whether the stream is seekable.
readableA flag indicating whether the stream is readable.
writableA flag indicating whether the stream is writable.

◆ ~Stream()

~Stream ( )
virtual

Destructor.

Member Function Documentation

◆ _init()

void _init ( FileHandle  handle,
bool  seekable,
bool  readable,
bool  writable 
)
protected

Initialize the stream for use with an open file.

Parameters
handleThe handle to an open file.
seekableA flag indicating whether the stream is seekable.
readableA flag indicating whether the stream is readable.
writableA flag indicating whether the stream is writable.

◆ close()

void close ( IOMode  mode = IOReadWrite)
virtual

Close the stream for reading, writing, or both.

Parameters
modeThe close mode.

Reimplemented in StreamSocket, and StreamPipe.

◆ getTimeout()

timespan_ms_t getTimeout ( ) const
inline

Get the stream I/O timeout, in milliseconds.

◆ isFullDuplex()

bool isFullDuplex ( ) const
inline

Test if the stream is full-duplex (i.e., supports both reading and writing).

◆ isHalfDuplex()

bool isHalfDuplex ( ) const
inline

Test if the stream is half-duplex (i.e., supports either reading or writing, but not both).

◆ isOpen()

bool isOpen ( ) const
inline

Test if the stream is open.

◆ isReadable()

bool isReadable ( ) const
inline

Test if the stream can be read from.

◆ isSeekable()

bool isSeekable ( ) const
inline

Test if the stream supports seeking.

◆ isWritable()

bool isWritable ( ) const
inline

Test if the stream can be written to.

◆ read() [1/7]

size_t read ( ByteBuffer buffer)
virtual

Read data from the stream into a ByteBuffer.

Parameters
bufferThe buffer to read into.
Returns
The number of bytes actually read.
Exceptions
IOExceptionIf the end-of-file was reached or some other I/O error occurred.

Reimplemented in StreamSocket.

◆ read() [2/7]

size_t read ( CharBuffer buffer)
virtual

Read data from the stream into a CharBuffer.

Parameters
bufferThe buffer to read into.
Returns
The number of characters actually read.
Exceptions
IOExceptionIf the end-of-file was reached or some other I/O error occurred.

Reimplemented in StreamSocket.

◆ read() [3/7]

size_t read ( Buffer< T > &  buffer,
size_t &  partial 
)
inline

Read data from the stream into a Buffer of arbitrary type.

If sizeof(T) is greater than 1 byte, then there can be no guarantee that the number of bytes read before a timeout or error occurs will be evenly divisible by sizeof(T). If the final element was partially read, the number of bytes of the element that were read will be stored in partial; this value should be passed unmodified to the next invocation of this method to continue reading from the appropriate offset within the partially-read element.

Parameters
bufferThe buffer to read into.
partialThe number of bytes remaining to read for a partially-read element; on return, the number of bytes read of a partially-read element, or 0 if the last element was read completely. Should be set to 0 prior to the first call to this method for a fresh buffer.
Returns
The number of whole elements actually read.
Exceptions
IOExceptionIf the end-of-file was reached or some other I/O error occurred.

◆ read() [4/7]

size_t read ( byte_t buffer,
size_t  buflen 
)
virtual

Read data from the stream into a raw buffer.

Parameters
bufferThe buffer to read into.
buflenThe number of bytes to read.
Returns
The number of bytes actually read.
Exceptions
IOExceptionIf the end-of-file was reached or some other I/O error occurred.

Reimplemented in StreamSocket.

◆ read() [5/7]

size_t read ( byte_t buffer,
size_t  buflen,
int64_t  offset,
AsyncIOTask task 
)

Read data asynchronously from the stream into a raw buffer.

Parameters
bufferThe buffer to read into.
buflenThe number of bytes to read.
offsetThe file offset to read from.
taskThe async I/O control block for monitoring the operation.
Returns
The number of bytes actually read, if the operation completed immediately, otherwise 0 to indicate that the operation has begun.
Exceptions
IOExceptionIf an I/O error occurred.

◆ read() [6/7]

size_t read ( ByteBuffer buffer,
int64_t  offset,
AsyncIOTask task 
)

Read data asynchronously from the stream into a Buffer.

Parameters
bufferThe Buffer to read into. This object must not be destroyed before the asynchronous I/O operation is completed or cancelled.
offsetThe file offset to read from.
taskThe async I/O control block for monitoring the operation.
Returns
The number of bytes actually read, if the operation completed immediately, otherwise 0 to indicate that the operation has begun.
Exceptions
IOExceptionIf an I/O error occurred.

◆ read() [7/7]

size_t read ( MemoryBlock vec,
uint_t  count 
)
virtual

Read data from the stream into a series of I/O buffers.

This operation is known as "vector read" or "scatter read." The buffers are read into in order. On systems that support it, the operation is performed with a single system call.

Parameters
vecAn array of buffers to read into.
countThe number of buffers in the array.
Exceptions
IOExceptionIf the end-of-file was reached or some other I/O error occurred.

Reimplemented in StreamSocket.

◆ readFully() [1/4]

size_t readFully ( ByteBuffer buffer,
size_t  count = 0 
)
virtual

Read data from the stream into a ByteBuffer, until either the buffer is full or an error or timeout occurs.

Parameters
bufferThe buffer to read into.
countThe number of bytes to read. If 0 or greater than the number of bytes between the position and the limit, reads up to the limit.
Returns
The number of bytes actually read.
Exceptions
IOExceptionIf the end-of-file was reached or some other I/O error occurred.

◆ readFully() [2/4]

size_t readFully ( CharBuffer buffer,
size_t  count = 0 
)
virtual

Read data from the stream into a CharBuffer, until either the buffer is full or an error or timeout occurs.

Parameters
bufferThe buffer to read into.
countThe number of characters to read. If 0 or greater than the number of bytes between the position and the limit, reads up to the limit.
Returns
The number of bytes actually read.
Exceptions
IOExceptionIf the end-of-file was reached or some other I/O error occurred.

◆ readFully() [3/4]

size_t readFully ( Buffer< T > &  buffer,
size_t &  partial 
)
inline

Read data from the stream into a Buffer of arbitrary type, until either the buffer is full or an error or timeout occurs.

If sizeof(T) is greater than 1 byte, then there can be no guarantee that the number of bytes read before a timeout or error occurs will be evenly divisible by sizeof(T). If the final element was partially read, the number of bytes of the element that were read will be stored in partial; this value should be passed unmodified to the next invocation of this method to continue reading from the appropriate offset within the partially-read element.

Parameters
bufferThe buffer to read into.
partialThe number of bytes remaining to read for a partially-read element; on return, the number of bytes read of a partially-read element, or 0 if the last element was read completely. Should be set to 0 prior to the first call to this method for a fresh buffer.
Returns
The number of whole elements actually read.
Exceptions
IOExceptionIf the end-of-file was reached or some other I/O error occurred.

◆ readFully() [4/4]

size_t readFully ( byte_t buffer,
size_t  buflen 
)
virtual

Read data from the stream into a raw buffer, until either the buffer is full or an error or timeout occurs.

Parameters
bufferThe buffer to read into.
buflenThe number of bytes to read.
Returns
The number of bytes actually read.
Exceptions
IOExceptionIf the end-of-file was reached or some other I/O error occurred.

◆ seek()

int64_t seek ( int64_t  offset,
SeekMode  mode = SeekAbsolute 
)
virtual

Reposition the seek pointer in the stream.

Parameters
offsetThe new offset.
modeThe seek mode.
Returns
The new position of the seek pointer.
Exceptions
IOExceptionIf the stream does not support seeking, or if some other I/O error occurred.

◆ setTimeout()

void setTimeout ( timespan_ms_t  timeout)
virtual

Set the stream I/O timeout, in milliseconds.

A timeout of 0 indicates no timeout, and a timeout of -1 indicates infinite timeout (blocking I/O).

Reimplemented in StreamSocket, and SerialPort.

◆ tell()

int64_t tell ( )
virtual

Get the current (absolute) offset of the seek pointer.

Returns
The current offset, from the beginning of the stream.
Exceptions
IOExceptionIf the stream does not support seeking, or if some other I/O error occurred.

◆ write() [1/7]

size_t write ( const byte_t buffer,
size_t  buflen,
int64_t  offset,
AsyncIOTask task 
)

Write data asynchronously to the stream from a raw buffer.

Parameters
bufferThe buffer to write.
buflenThe number of bytes to write.
offsetThe file offset to write to.
taskThe async I/O control block for monitoring the operation.
Returns
The number of bytes actually written, if the operation completed immediately, otherwise 0 to indicate that the operation has begun.
Exceptions
IOExceptionIf an I/O error occurred.

◆ write() [2/7]

size_t write ( ByteBuffer buffer,
int64_t  offset,
AsyncIOTask task 
)

Write data asynchronously to the stream from a Buffer.

Parameters
bufferThe Buffer to write. This object must not be destroyed before the asynchronous I/O operation is completed or cancelled.
offsetThe file offset to write to.
taskThe async I/O control block for monitoring the operation.
Returns
The number of bytes actually written, if the operation completed immediately, otherwise 0 to indicate that the operation has begun.
Exceptions
IOExceptionIf an I/O error occurred.

◆ write() [3/7]

size_t write ( ByteBuffer buffer)
virtual

Write data to the stream from a ByteBuffer.

Parameters
bufferThe buffer to write.
Returns
The number of bytes actually written.
Exceptions
IOExceptionIf an I/O error occurred.

Reimplemented in StreamSocket.

◆ write() [4/7]

size_t write ( CharBuffer buffer)
virtual

Write data to the stream from a CharBuffer.

Parameters
bufferThe buffer to write.
Returns
The number of characters actually written.
Exceptions
IOExceptionIf an I/O error occurred.

Reimplemented in StreamSocket.

◆ write() [5/7]

size_t write ( Buffer< T > &  buffer,
size_t &  partial 
)
inline

Write data to the stream from a Buffer of arbitrary type.

If sizeof(T) is greater than 1 byte, then there can be no guarantee that the number of bytes written before a timeout or error occurs will be evenly divisible by sizeof(T). If the final element was partially written, the number of bytes of the element that were written will be stored in partial; this value should be passed unmodified to the next invocation of this method to continue writing from the appropriate offset within the partially-written element.

Parameters
bufferThe buffer to write.
partialThe number of bytes remaining to write for a partially-written element; on return, the number of bytes written of a partially-written element, or 0 if the last element was written completely. Should be set to 0 prior to the first call to this method for a fresh buffer.
Returns
The number of whole elements actually written.
Exceptions
IOExceptionIf an I/O error occurred.

◆ write() [6/7]

size_t write ( const byte_t buffer,
size_t  buflen 
)
virtual

Write data to the stream from a raw buffer, until either the entire buffer is written or an error or timeout occurs.

Parameters
bufferA pointer to the buffer.
buflenThe number of bytes to write.
Returns
The number of bytes actually written.
Exceptions
IOExceptionIf an I/O error occurred.

Reimplemented in StreamSocket.

◆ write() [7/7]

size_t write ( const MemoryBlock vec,
uint_t  count 
)
virtual

Write data to the stream from a series of I/O buffers.

This operation is known as "vector write" or "gather write." The buffers are written in order. On systems that support it, the operation is performed with a single system call.

Parameters
vecAn array of buffers to write.
countThe number of buffers in the array.
Exceptions
IOExceptionIf an I/O error occurred.

Reimplemented in StreamSocket.

◆ writeFully() [1/4]

size_t writeFully ( ByteBuffer buffer)
virtual

Write data to the stream from a ByteBuffer, until either the entire buffer is written or an error or timeout occurs.

Parameters
bufferThe buffer to write.
Returns
The number of bytes actually written.
Exceptions
IOExceptionIf and I/O error occurred.

◆ writeFully() [2/4]

size_t writeFully ( CharBuffer buffer)
virtual

Write data to the stream from a CharBuffer, until either the entire buffer is written or an error or timeout occurs.

Parameters
bufferThe buffer to write.
Returns
The number of bytes actually written.
Exceptions
IOExceptionIf an I/O error occurred.

◆ writeFully() [3/4]

size_t writeFully ( Buffer< T > &  buffer,
size_t &  partial 
)
inline

Write data to the stream from a Buffer of arbitrary type, until either the entire buffer is written or an error or timeout occurs.

If sizeof(T) is greater than 1 byte, then there can be no guarantee that the number of bytes written before a timeout or error occurs will be evenly divisible by sizeof(T). If the final element was partially written, the number of bytes of the element that were written will be stored in partial; this value should be passed unmodified to the next invocation of this method to continue writing from the appropriate offset within the partially-written element.

Parameters
bufferThe buffer to write.
partialThe number of bytes remaining to write for a partially-written element; on return, the number of bytes written of a partially-written element, or 0 if the last element was written completely. Should be set to 0 prior to the first call to this method for a fresh buffer.
Returns
The number of whole elements actually written.
Exceptions
IOExceptionIf an I/O error occurred.

◆ writeFully() [4/4]

size_t writeFully ( const byte_t buffer,
size_t  buflen 
)
virtual

Write data to the stream from a raw buffer.

Parameters
bufferA pointer to the buffer.
buflenThe number of bytes to write.
Returns
The number of bytes actually written.
Exceptions
IOExceptionIf an I/O error occurred.

Friends And Related Function Documentation

◆ Process

friend class Process
friend

Member Data Documentation

◆ MAX_IOBLOCK_COUNT

const uint_t MAX_IOBLOCK_COUNT = 16
static

The maximum number of I/O buffers that can be passed to the vector I/O methods.


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